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Sample records for impact basins margaritifer

  1. The geologic history of Margaritifer basin, Mars

    Science.gov (United States)

    Salvatore, M. R.; Kraft, M. D.; Edwards, Christopher; Christensen, P.R.

    2016-01-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava (ULM) outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre Basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  2. Geology of Holden Crater and the Holden and Ladon Multi-Ring Impact Basins, Margaritifer Terra, Mars

    Science.gov (United States)

    Irwin, R. P., III; Grant, J. A.

    2008-01-01

    Geologic mapping at 1:500K scale of Mars quads 15s027, 20s027, 25s027, and 25s032 (Fig. 1) is in progress to constrain the geologic and geomorphic history of southwestern Margaritifer Terra. This work builds on earlier maps at 1:5M [1] and 1:15M scales [2], recent to concurrent 1:500Kscale mapping of adjacent areas to the east [3-5], and studies of drainage basin evolution along the Uzboi-Ladon-M (ULM; the third valley in the sequence has no formal name) Valles basin overflow system and nearby watersheds [6-9]. Two of the six landing sites under consideration for the Mars Science Laboratory rover are in this map area, targeting finely layered, phyllosilicate-rich strata and alluvial fans in Holden crater [10-12] (26degS, 34degW, 150 km diameter) or deposits southeast of a likely delta in Eberswalde crater [13-16] (24degS, 33degW, 50 km in diameter). Diverse processes including larger and smaller impacts, a wide range in fluvial activity, and local to regional structural influences have all affected the surface morphology.

  3. Geologic Map of MTM -20012 and -25012 Quadrangles, Margaritifer Terra Region of Mars

    Science.gov (United States)

    Grant, J. A.; Wilson, S.A.; Fortezzo, C.M.; Clark, D.A.

    2009-01-01

    Mars Transverse Mercator (MTM) -20012 and -25012 quadrangles (lat 17.5 deg - 27.5 deg S., long 345 deg - 350 deg E.) cover a portion of Margaritifer Terra near the east end of Valles Marineris. The map area consists of a diverse assemblage of geologic surfaces including isolated knobs of rugged mountainous material, heavily cratered and dissected ancient highland material, a variety of plains materials, chaotic terrain materials, and one of the highest densities of preserved valleys and their associated deposits on the planet (Saunders, 1979; Baker, 1982; Phillips and others, 2000, 2001). The map area is centered on a degraded, partially filled, ~200-km-diameter impact structure (lat 22 deg S., long 347.5 deg E.), informally referred to as Parana basin, located between Parana Valles to the east and Loire Valles to the west. Parana Valles is a network of multidigitate, mostly east-west-oriented valleys that flowed west and discharged into Parana basin (Grant, 1987, 2000; Grant and Parker, 2002). Loire Valles, broadly comparable in length to the Grand Canyon on Earth, has a deeply incised channel within the map area that originates at the west-northwest edge of Erythraeum Chaos within Parana basin (Grant, 1987, 2000; Grant and Parker, 2002; Strom and others, 2000). Parana and Loire Valles, combined with Samara Valles to the west, form one of the most laterally extensive, well-integrated valley networks on Mars (Grant, 2000) and record a long history of modification by fluvial processes. The origin and morphology of the valley networks, therefore, provide insight into past environmental conditions, whereas their relation with other landforms helps constrain the timing and role of fluvial processes in the evolution and modification of the Margaritifer Terra region.

  4. Geologic map of MTM -15027, -20027, -25027, and -25032 quadrangles, Margaritifer Terra region of Mars

    Science.gov (United States)

    Irwin, Rossman P.; Grant, John A.

    2013-01-01

    Mars Transverse Mercator (MTM) quadrangles −15027, −20027, −25027, and −25032 (lat 12.5°−28° S., long 330°−335° E. and lat 22.5°−28° S., long 324.5°−330° E.) in southwestern Margaritifer Terra include diverse erosional landforms, sedimentary deposits, and tectonic structures that record a long geologic and geomorphic history. The northeastern regional slope of the pre-Noachian crustal dichotomy (as expressed along the Chryse trough) and structures of the informally named Middle Noachian or older Holden and Ladon impact basins dominate the topography of the map area. A series of mesoscale outflow channels, Uzboi, Ladon, and Morava Valles, integrated these formerly enclosed basins by overflow and incision around the Noachian/Hesperian transition, although some flooding may have occurred earlier. The area includes excellent examples of Late Noachian to Hesperian valley networks, dissected crater rims, alluvial fans, deltas, and light-toned layered deposits, particularly in Holden and Eberswalde craters. Structural forms include Tharsis-radial grabens, Hesperian wrinkle ridges, floor-fractured impact craters, and severely disrupted chaotic terrains. These well-preserved landforms and sedimentary deposits represent multiple erosional epochs and discrete flooding events, which provide significant insight into the geomorphic processes and climate change on early Mars.

  5. Precision Mapping of Valley Networks in Margaritifer Sinus, Mars

    Science.gov (United States)

    Stepinski, T. F.; Luo, W.; Qi, Y.

    2007-03-01

    Valley networks in Margaritifer Sinus quadrangle are mapped using a computer algorithm. The new map reveals wider existence of valleys than has been inferred from older maps. This suggests runoff as the primary mechanism for origin of the valleys.

  6. Hydraulic Inferences for Mars From Geologic Mapping in Margaritifer Terra, Mars and Measurements of Terrestrial Analogs.

    Science.gov (United States)

    Fortezzo, C. M.; Williams, K. K.; Springer, A. E.

    2006-12-01

    Past hydrogeologic models of Mars have focused primarily on exploring a link between large scale groundwater systems and the Martian outflow channels. These groundwater models have generally given only slight consideration to the occurrence of smaller-scale valley network that dissect much of the southern highlands. Ongoing geologic and geomorphic mapping in 6 Mars Transverse Mercator 1:500K quadrangles (17.5ºS - 27.5ºS and 345ºE - 360ºE) in southeast Margaritifer Terra, Mars, shows valley networks are often associated with the internal and external slopes of the impact basin but are absent on the basin floor. We propose a sequence of ponding in the basin followed by infiltration into the subsurface, transmission down the regional slope and sapping valleys forming on the crater flanks. The Martian valley morphologies are analogous with morphologies of terrestrial spring-fed sapping processes (i.e., amphitheater-shaped heads, stubby tributaries, steep walls, and U-shaped valleys that maintain consistent width-depth ratios along their length). Flow measurements from spring-fed channels in the Navajo Sandstone near Escalante, Utah supply data from areas actively forming sapping valleys and provide insight into the interaction between surface-water and groundwater. Measurements taken during pre-monsoon and post-snow melt run-off and planned post- monsoonal measurements will provide a range of discharge values furnishing data to model the interaction of subsurface- and surface-water flow on Mars. Published stratigraphic models of Mars postulate that the upper kilometer of material is ejecta related well-mixed unsorted debris ranging from meter sized blocks down to dust sized particles overlying fractured bedrock. Detailed mapping using high resolution datasets allows for accurate characterization of surficial material properties on a local scale which will help to better understand influences on hydrologic variables (i.e. permeability, hydraulic conductivity, etc

  7. Large-scale fluid-deposited mineralization in Margaritifer Terra, Mars

    Science.gov (United States)

    Thomas, Rebecca J.; Potter-McIntyre, Sally L.; Hynek, Brian M.

    2017-07-01

    Mineral deposits precipitated from subsurface-sourced fluids are a key astrobiological detection target on Mars, due to the long-term viability of the subsurface as a habitat for life and the ability of precipitated minerals to preserve biosignatures. We report morphological and stratigraphic evidence for ridges along fractures in impact crater floors in Margaritifer Terra. Parallels with terrestrial analog environments and the regional context indicate that two observed ridge types are best explained by groundwater-emplaced cementation in the shallow subsurface and higher-temperature hydrothermal deposition at the surface, respectively. Both mechanisms have considerable astrobiological significance. Finally, we propose that morphologically similar ridges previously documented at the Mars 2020 landing site in NE Syrtis Major may have formed by similar mechanisms.

  8. Impact melt of the lunar Crisium multiring basin

    Science.gov (United States)

    Spudis, P. D.; Sliz, M. U.

    2017-02-01

    New geological mapping of the Crisium basin on the Moon has revealed exposures of the basin impact melt sheet. The melt sheet has a feldspathic highland composition, somewhat more mafic than the melt sheet of the Orientale basin, but less mafic than comparable deposits around the Imbrium basin. These newly recognized deposits would be ideal locations to directly sample Crisium basin impact melt, material whose study would yield insight into the composition of the lunar crust, the time of formation of the basin, and the large impact process.

  9. Two new records of Valenciennea helsdingenii (Perciformes: Gobiidae) and Chromis margaritifer (Perciformes: Pomacentridae) from Jeju Island, Korea

    Science.gov (United States)

    Myoung, Jung-Goo; Myoung, Se Hun; Hwang, In-Seo; Kim, Byung-il; Kim, Jin-Koo

    2014-03-01

    Two specimens of Valenciennea helsdingenii and one specimen of Chromis margaritifer were collected on scuba in October 2011 from Jeju Island, Korea. V. helsdingenii is characterized by a body with two dark stripes that connect the head and caudal fin, and a large dark spot between the third and sixth dorsal fin spines. C. margaritifer is characterized by a body that is dark brown anteriorly but white posteriorly at the boundary between the fifth dorsal fin soft ray and the ninth anal fin soft ray. The Korean name `Bok-gi-mang-duk-sok' is proposed for the genus Valenciennea, the name `Du-jul-bok-gi-mang-duk' is proposed for the species V. helsdingenii, and the name `Huinggo-ri-ja-ri-dom' is proposed for C. margaritifer.

  10. Distribution, Statistics, and Resurfacing of Large Impact Basins on Mercury

    Science.gov (United States)

    Fassett, Caleb I.; Head, James W.; Baker, David M. H.; Chapman, Clark R.; Murchie, Scott L.; Neumann, Gregory A.; Oberst, Juergen; Prockter, Louise M.; Smith, David E.; Solomon, Sean C.; Strom, Robert G.; Xiao, Zhiyong; Zuber, Maria T.

    2012-01-01

    The distribution and geological history of large impact basins (diameter D greater than or equal to 300 km) on Mercury is important to understanding the planet's stratigraphy and surface evolution. It is also informative to compare the density of impact basins on Mercury with that of the Moon to understand similarities and differences in their impact crater and basin populations [1, 2]. A variety of impact basins were proposed on the basis of geological mapping with Mariner 10 data [e.g. 3]. This basin population can now be re-assessed and extended to the full planet, using data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Note that small-to- medium-sized peak-ring basins on Mercury are being examined separately [4, 5]; only the three largest peak-ring basins on Mercury overlap with the size range we consider here. In this study, we (1) re-examine the large basins suggested on the basis of Mariner 10 data, (2) suggest additional basins from MESSENGER's global coverage of Mercury, (3) assess the size-frequency distribution of mercurian basins on the basis of these global observations and compare it to the Moon, and (4) analyze the implications of these observations for the modification history of basins on Mercury.

  11. Evolution of the Rembrandt impact basin on Mercury.

    Science.gov (United States)

    Watters, Thomas R; Head, James W; Solomon, Sean C; Robinson, Mark S; Chapman, Clark R; Denevi, Brett W; Fassett, Caleb I; Murchie, Scott L; Strom, Robert G

    2009-05-01

    MESSENGER's second Mercury flyby revealed a ~715-kilometer-diameter impact basin, the second-largest well-preserved basin-scale impact structure known on the planet. The Rembrandt basin is comparable in age to the Caloris basin, is partially flooded by volcanic plains, and displays a unique wheel-and-spoke-like pattern of basin-radial and basin-concentric wrinkle ridges and graben. Stratigraphic relations indicate a multistaged infilling and deformational history involving successive or overlapping phases of contractional and extensional deformation. The youngest deformation of the basin involved the formation of a approximately 1000-kilometer-long lobate scarp, a product of the global cooling and contraction of Mercury.

  12. Evaluation of drought regimes and impacts in the Limpopo basin

    OpenAIRE

    B. F. Alemaw; J.-M. Kileshye-Onema

    2014-01-01

    Drought is a common phenomenon in the Limpopo River basin. In essence, droughts are long–term hydro-meteorological events affecting vast regions and causing significant non-structural damages. In the interest of riparian states' joint integrated water resources development and management of the Limpopo basin, inter regional drought severity and its impacts should be understood. The study focussed on case studies in the basin which is subdivided into four homogeneous r...

  13. Chicxulub impact basin: Gravity characteristics and implications for basin morphology and deep structure

    Science.gov (United States)

    Sharpton, Virgil L.; Burke, Kevin; Hall, Stuart A.; Lee, Scott; Marin, Luis E.; Suarez, Gerardo; Quezada-Muneton, Juan Manuel; Urrutia-Fucugauchi, Jaime

    1993-01-01

    The K-T-aged Chicxulub Impact Structure is buried beneath the Tertiary carbonate rocks of the Northern Yucatan Platform. Consequently its morphology and structure are poorly understood. Reprocessed Bouguer (onshore) and Free Air (offshore) gravity data over Northern Yucatan reveal that Chicxulub may be a 200-km-diameter multi-ring impact basin with at least three concentric basin rings. The positions of these rings follow the square root of 2 spacing rule derived empirically from analysis of multi-ring basins on other planets indicating that these rings probably correspond to now-buried topographic basin rings. A forward model of the gravity data along a radial transect from the southwest margin of the structure indicates that the Chicxulub gravity signature is compatible with this interpretation. We estimate the basin rim diameter to be 204 +/- 16 km and the central peak ring diameter (D) is 104 +/- 6 km.

  14. Geologic Evolution of the Schiaparelli Impact Basin, Mars

    Science.gov (United States)

    Jaret, S. J.; Albin, E. F.

    2002-09-01

    Situated in the eastern Terra Meridiani region of the Martian cratered uplands is an ancient 470-km diameter basin called Schiaparelli. In this investigation, Viking Orbiter image mosaics were used as a base to create a detailed geologic map of this impact structure. High resolution Global Surveyor MOC and MOLA data provided information for the interpretation of individual map units. The basin rim (Br) separates distinct sets of interior and exterior units. Within the basin, the following units are found: a) [Im] interior mountain (inner peak ring), b) [Ih] interior hilly material (fallback ejecta), c) [Irp] interior ridged plains (lava flows), and d) [Isp] interior smooth plains (lacustrine deposits). The exterior basin units include: a) [Cu] cratered upland material (target material), b) [Em] exterior mountain (basin ring) c) [Cd] cratered dissected material (continuous ejecta), d) [Erp] exterior ridged plains (lava flows), and e) [Esp] exterior smooth plains (lacustrine deposits). These findings provide clues about the geologic history of Schiaparelli basin.

  15. Climate Change Impacts on the Congo Basin Region

    NARCIS (Netherlands)

    Ludwig, F.; Franssen, W.; Jans, W.W.P.; Kruijt, B.; Supit, I.

    2012-01-01

    This report presents analyses of climate change impacts in the Congo Basin on water for agriculture and hydropower, forest ecosystem functioning and carbon storage and impacts of climate variability and change on future economic development. To quantify the impacts of future climate we developed a m

  16. Impact crater and basin control of igneous processes on Mars

    Science.gov (United States)

    Schultz, P. H.; Glicken, H.

    1979-01-01

    The possible role of impact craters in controlling local Martian endogenic activity is reviewed. Martian impact craters exhibiting evidence for endogenic modification are considered, including the style of modification. In addition, the cooling history of a mafic body intruded beneath impact craters of different sizes which contain water-ice deposits are examined, and results are related to modified Martian craters. This analysis is extended to basin-sized structures, and evidence for impact basin control of major volcanic and tectonic provinces is considered.

  17. Identifying and Characterizing Impact Melt Outcrops in the Nectaris Basin

    Science.gov (United States)

    Cohen, B. A.; Lawerence, S. J.; Petro, N. E.; Bart, G. D.; Clegg-Watkins, R. N.; Denevi, B. W.; Ghent, R. R.; Klima, R. L.; Morgan, G. A.; Spudis, P. D.; Stopar, J. D.

    2016-01-01

    The Nectaris Basin is an 820-km diameter, multi-ring impact basin located on the near side of the Moon. Nectaris is a defining stratigraphic horizon based on relationships between ejecta units, giving its name to the Nectarian epoch of lunar history. Lunar basin chronology based on higher resolution LRO imagery and topography, while assigning some important basins like Serenitatis to pre-Nectarian time, were generally consistent with those previously derived. Based on this stratigraphy, at least 11 large basins formed in the time between Nectaris and Imbrium. The absolute age of Nectaris, therefore, is a crucial marker in the lunar time-stratigraphic sequence for understanding the impact flux on the Moon, and by extension, the entire inner solar system. For several decades, workers have attempted to constrain the age of the Nectaris basin through radiometric dating of lunar samples. However, there is little agreement on which samples in our collection represent Nectaris, if any, and what the correct radiometric age of such samples is. The importance of the age of Nectaris goes far beyond assigning a stratigraphic marker to lunar chronology. Several dynamical models use Nectaris as their pin date, so that this date becomes crucial in understanding the time-correlated effects in the rest of the solar system. The importance of the Nectaris basin age, coupled with its nearside, mid-latitude location, make remnants of the impact-melt sheet an attractive target for a future mission, either for in-situ dating or for sample return. We have started exploring this possibility. We have begun a consortium data-analysis effort bringing multiple datasets and analysis methods to bear on these putative impact-melt deposits to characterize their extent, elemental composition and mineralogy, maturity and geologic setting, and to identify potential landing sites that meet both operational safety and science requirements.

  18. Evaluation of drought regimes and impacts in the Limpopo basin

    Science.gov (United States)

    Alemaw, B. F.; Kileshye-Onema, J.-M.

    2014-01-01

    Drought is a common phenomenon in the Limpopo River basin. In essence, droughts are long-term hydro-meteorological events affecting vast regions and causing significant non-structural damages. In the interest of riparian states' joint integrated water resources development and management of the Limpopo basin, inter regional drought severity and its impacts should be understood. The study focussed on case studies in the basin which is subdivided into four homogeneous regions owing to topographic and climate variations based on the previous work of the same authors. Using the medium range time series of the Standardized Precipitation Index (SPI) as an indicator of drought, for each homogeneous region monthly and annual Severity-Area-Frequency (SAF) curves and maps of probability of drought occurrence were constructed. The results indicated localized severe droughts in higher frequencies, while only moderate to severe low frequency droughts may spread over wider areas in the basin. The region-level Drought-Severity Indices can be used as indicators for planning localized interventions and drought mitigation efforts in the basin. The approach can also be used to develop improved drought indicators, to assess the relationship between drought hazard and vulnerability and to enhance the performance of methods currently used for drought forecasting. Results on the meteorological drought linkage with hydrological and vegetation or agricultural drought indices are presented as means of validation of the specific drought regimes and their localized impact in each homogeneous region. In general, this preliminary investigation reveals that the western part of the basin will face a higher risk of drought when compared to other regions of the Limpopo basin in terms of the medium-term drought. The Limpopo basin is water stressed and livelihood challenges remain at large, thus impacts of droughts and related resilience options should be taken into account in the formulation of

  19. Evaluation of drought regimes and impacts in the Limpopo basin

    Directory of Open Access Journals (Sweden)

    B. F. Alemaw

    2014-01-01

    Full Text Available Drought is a common phenomenon in the Limpopo River basin. In essence, droughts are long–term hydro-meteorological events affecting vast regions and causing significant non-structural damages. In the interest of riparian states' joint integrated water resources development and management of the Limpopo basin, inter regional drought severity and its impacts should be understood. The study focussed on case studies in the basin which is subdivided into four homogeneous regions owing to topographic and climate variations based on the previous work of the same authors. Using the medium range time series of the Standardized Precipitation Index (SPI as an indicator of drought, for each homogeneous region monthly and annual Severity-Area-Frequency (SAF curves and maps of probability of drought occurrence were constructed. The results indicated localized severe droughts in higher frequencies, while only moderate to severe low frequency droughts may spread over wider areas in the basin. The region-level Drought-Severity Indices can be used as indicators for planning localized interventions and drought mitigation efforts in the basin. The approach can also be used to develop improved drought indicators, to assess the relationship between drought hazard and vulnerability and to enhance the performance of methods currently used for drought forecasting. Results on the meteorological drought linkage with hydrological and vegetation or agricultural drought indices are presented as means of validation of the specific drought regimes and their localized impact in each homogeneous region. In general, this preliminary investigation reveals that the western part of the basin will face a higher risk of drought when compared to other regions of the Limpopo basin in terms of the medium-term drought. The Limpopo basin is water stressed and livelihood challenges remain at large, thus impacts of droughts and related resilience options should be taken into account in the

  20. Chemostratigraphy of the Sudbury impact basin fill: Volatile metal loss and post-impact evolution of a submarine impact basin

    Science.gov (United States)

    O'Sullivan, Edel M.; Goodhue, Robbie; Ames, Doreen E.; Kamber, Balz S.

    2016-06-01

    The 1.85 Ga Sudbury structure provides a unique opportunity to study the sequence of events that occurred within a hydrothermally active subaqueous impact crater during the late stages of an impact and in its aftermath. Here we provide the first comprehensive chemostratigraphic study for the lower crater fill, represented by the ca. 1.4 km thick Onaping Formation. Carefully hand-picked ash-sized matrix of 81 samples was analysed for major elements, full trace elements and C isotopes. In most general terms, the composition of the clast-free matrix resembles that of the underlying melt sheet. However, many elements show interesting chemostratigraphies. The high field strength element evolution clearly indicates that the crater rim remained intact during the deposition of the entire Onaping Formation, collapsing only at the transition to the overlying Onwatin Formation. An interesting feature is that several volatile metals (e.g., Pb, Sb) are depleted by >90% in the lower Onaping Formation, suggesting that the impact resulted in a net loss of at least some volatile species, supporting the idea of "impact erosion," whereby volatile elements were vaporised and lost to space during impact. Reduced C contents in the lower Onaping Formation are low (sensitive trace metal chemostratigraphies (e.g., V and Mo) suggest that the basin was anoxic and possibly euxinic and became inhabited by plankton, whose rain-down led to a reservoir effect in certain elements (e.g., Mo). This lasted until the crater rim was breached, the influx of fresh seawater promoting renewed productivity. If the Sudbury basin is used as an analogue for the Hadean and Eoarchaean Earth, our findings suggest that hydrothermal systems, capable of producing volcanogenic massive sulphides, could develop within the rims of large to giant impact structures. These hydrothermal systems did not require mid-ocean ridges and implicitly, the operation of plate tectonics. Regardless of hydrothermal input, enclosed

  1. Could Giant Basin-Forming Impacts Have Killed Martian Dynamo?

    Science.gov (United States)

    Kuang, W.; Jiang, W.; Roberts, J.; Frey, H. V.

    2014-01-01

    The observed strong remanent crustal magnetization at the surface of Mars suggests an active dynamo in the past and ceased to exist around early to middle Noachian era, estimated by examining remagnetization strengths in extant and buried impact basins. We investigate whether the Martian dynamo could have been killed by these large basin-forming impacts, via numerical simulation of subcritical dynamos with impact-induced thermal heterogeneity across the core-mantle boundary. We find that subcritical dynamos are prone to the impacts centered on locations within 30 deg of the equator but can easily survive those at higher latitudes. Our results further suggest that magnetic timing places a strong constraint on postimpact polar reorientation, e.g., a minimum 16 deg polar reorientation is needed if Utopia is the dynamo killer.

  2. Environmental Impact of Eu Policies On Acheloos River Basin, Greece

    Science.gov (United States)

    Skoulikidis, N.; Nikolaidis, N. P.; Oikonomopoulou, A.; Batzias, F.

    The environmental impact of EU policies aiming at protecting surface and ground wa- ters are being assessed in the Acheloos River Basin, Greece as part of a Joint Research Centre (JRC) / DG Environment (DG Env) funded project. The basin offers the possi- bility of studying the impact of EU policies on a multitude of aquatic ecosystems: four artificial and four natural lakes and a large estuary with important hydrotops (lagoons, coastal salt lacustrine and freshwater marshes, etc.) that belong to the NATURA 2000 sites or are protected by the RAMSAR Convention. A database has been developed that includes all available information on sources, fluxes, and concentration levels of nutrients and selected heavy metals from prior and current research programs at the Acheloos River Basin and coastal environment. This information has been used to identify the environmental pressures and develop nutrient budgets for each sub-basin of the watershed to assess the relative contributions of nutrients from various land uses. The mathematical model HSPF is being used to model the hydrology and nitro- gen fate and transport in the watershed. Management scenarios will be developed and modelling exercises will be carried out to assess the impacts of the scenarios. Eco- nomic analysis of the nutrient management scenarios will be conducted to evaluate the costs associated with management practices for reaching acceptable water quality status.

  3. The Maturely, Immature Orientale Impact Basin

    Science.gov (United States)

    Cahill, J. T.; Lawrence, D. J.; Stickle, A. M.; Delen, O.; Patterson, G.; Greenhagen, B. T.

    2015-12-01

    Lunar surface maturity is consistently examined using the NIR optical maturity parameter (OMAT) [1]. However, the NIR only provides a perspective of the upper microns of the lunar surface. Recent studies of Lunar Prospector (LP) and Lunar Reconnaissance Orbiter data sets are now demonstrating additional measures of maturity with sensitivities to greater depths (~2 m) in the regolith. These include thermal infrared, S-band radar, and epithermal neutron data sets [2-4]. Interestingly, each of these parameters is directly comparable to OMAT despite each measuring slightly different aspects of the regolith. This is demonstrated by Lawrence et al. [3] where LP-measured non-polar highlands epithermal neutrons trend well with albedo, OMAT, and the Christensen Feature (CF). Lawrence et al. [3] used these data to derive and map highlands hydrogen (H) which is dominantly a function of H-implantation. With this in mind, areas of enriched-H are mature, while areas of depleted H are immature. Surface roughness as measured by S-band radar [4], also provides a measure of maturity. In this case, the circular polarization ratio (CPR) is high when rough and immature, and low when smooth and mature. Knowing this, one can recognize areas in the non-polar lunar highlands that show contradictory measures of maturity. For example, while many lunar localities show consistently immature albedo, OMAT, CF, CPR, and H concentrations (e.g., Tycho), others do not. Orientale basin is the most prominent example, shown to have immature CPR, CF, and H concentrations despite a relatively mature albedo and OMAT values as well as an old age determination (~3.8 Ga). To better understand how the lunar regolith is weathering in the upper 1-2 m of regolith with time we examine the Orientale basin relative to other highlands regions. [1] Lucey et al. (2000) JGR, 105, 20377; [2] Lucey et al. (2013) LPSC, 44, 2890; [3] Lawrence et al. (2015) Icarus, j.icarus.2015.01.005; [4] Neish et al. (2013) JGR, 118

  4. Climate Change Impacts in a Colombian Andean Tropical Basin

    Science.gov (United States)

    Ocampo, O. L.; Vélez, J. J.; Londoño, A.

    2012-12-01

    Climate change and climate variability have a large impact on water resources. Developing regions have less capacity to prepare for, respond to, and recover from climate-related hazards and effects, and then, populations may be disproportionately affected. In Colombia, the geographical location and the marked irregularity in the terrain, give as a result, a complex climate. These factors have contributed to the water supply of the territory. Unfortunately, the visualization of abundant and inexhaustible water resources created a great disregard for them. Besides, the water supply is not distributed uniformly across the country, and then there is water-deficit in some areas as Andean Region, where the largest population and the main development centers are located. In recent decades, water conflicts have emerged locally and regionally, which have generated a crisis in the allocation mechanisms and have improved the understanding of the water situation in Colombia. The Second National Communication to CCMNU alerts on possible future consequences of climate change and the need for regional studies for understanding climate change impacts on the fragile ecosystems of high mountains as paramos and fog forest, which are water production regulators. Colombian water resources are greatly affected by changes in rainfall patterns influenced by El Niño and La Niña. The recent disasters in the 2010-2011 rainy seasons have caught the attention of not only the authorities but from the scientific community to explore strategies to improve water management by tracking, anticipating and responding to climate variability and climate change. Whereas sound water management is built upon long-term, the country is undertaking a pilot exercise for the integrated management of water resources, five Basins are selected, among them, is the Chinchiná River Basin; this Andean tropical Basin is located on the western slopes at the central range in the Andes between 4°48 and 5°12 N

  5. Sub-basin scale characterization of climate change vulnerability, impacts and adaptation in an Indian River basin

    NARCIS (Netherlands)

    Bhave, A.; Mishra, A.; Groot, A.M.E.

    2013-01-01

    Knowledge of climate change vulnerability and impacts is a prerequisite for formulating locally relevant climate change adaptation policies. A participatory approach has been used in this study to determine climate change vulnerability, impacts and adaptation aspects for the Kangsabati River basin,

  6. Supplemental Information For: Asymmetric Distribution of Lunar Impact Basins Caused by Variations in Target Properties

    Science.gov (United States)

    Miljkovic, Katarina; Wieczorek, Mark; Collins, Gareth S.; Laneuville, Matthieu; Neumann, Gregory A.; Melosh, H. Jay; Solomon, Sean C.; Phillips, Roger J.; Smith, David E.; Zuber, Maria T.

    2014-01-01

    Maps of crustal thickness derived from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission revealed more large impact basins on the nearside hemisphere of the Moon than on its farside. The enrichment in heat-producing elements and prolonged volcanic activity on the lunar nearside hemisphere indicate that the temperature of the nearside crust and uppermantle was hotter than that of the farside at the time of basin formation. Using the iSALE-2D hydrocode to model impact basin formation, we found that impacts on the hotter nearside would have formed basins up to two times larger than similar impacts on the cooler farside hemisphere. The size distribution of lunar impact basins is thus not representative of the earliest inner Solar system impact bombardment

  7. Asymmetric Distribution of Lunar Impact Basins Caused by Variations in Target Properties

    Science.gov (United States)

    Miljkovic, Katarina; Wieczorek, Mark A.; Collins, Gareth S.; Laneuville, Matthieu; Neumann, Gregory A.; Melosh, H. Jay; Solomon, Sean C.; Phillips, Roger J.; Smith, David E.; Zuber, Maria T.

    2014-01-01

    Maps of crustal thickness derived from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission revealed more large impact basins on the nearside hemisphere of the Moon than on its farside. The enrichment in heat-producing elements and prolonged volcanic activity on the lunar nearside hemisphere indicate that the temperature of the nearside crust and upper mantle was hotter than that of the farside at the time of basin formation. Using the iSALE-2D hydrocode to model impact basin formation, we found that impacts on the hotter nearside would have formed basins up to two times larger than similar impacts on the cooler farside hemisphere. The size distribution of lunar impact basins is thus not representative of the earliest inner Solar system impact bombardment.

  8. Pulling Marbles from a Bag: Deducing the Regional Impact History of the SPA Basin from Impact-Melt Rocks

    Science.gov (United States)

    Cohen, Barbara A.; Coker, Robert F.

    2010-01-01

    The South Pole Aitken (SPA) basin is the stratigraphically oldest identifiable lunar basin and is therefore one of the most important targets for absolute age-dating to help understand whether ancient lunar bombardment history smoothly declined or was punctuated by a cataclysm. A feasible near-term approach to this problem is to robotically collect a sample from near the center of the basin, where vertical and lateral mixing provided by post-basin impacts ensures that such a sample will be composed of small rock fragments from SPA itself, from local impact craters, and from faraway giant basins. The range of ages, intermediate spikes in the age distribution, and the oldest ages are all part of the definition of the absolute age and impact history recorded within the SPA basin.

  9. Large Impact Basins on Mercury: Global Distribution, Characteristics, and Modification History from MESSENGER Orbital Data

    Science.gov (United States)

    Fassett, Caleb I.; Head, James W.; Baker, David M. H.; Zuber, Maria T.; Neumann, Gregory A.; Solomon, Sean C.; Klimczak, Christian; Strom, Robert G.; Chapman, Clark R.; Prockter, Louise M.; Phillips, Roger J.; Oberst, Juergen; Preusker, Frank

    2012-01-01

    The formation of large impact basins (diameter D greater than or equal to 300 km) was an important process in the early evolution of Mercury and influenced the planet's topography, stratigraphy, and crustal structure. We catalog and characterize this basin population on Mercury from global observations by the MESSENGER spacecraft, and we use the new data to evaluate basins suggested on the basis of the Mariner 10 flybys. Forty-two certain or probable impact basins are recognized a few additional basins that may have been degraded to the point of ambiguity are plausible on the basis of new data but are classified as uncertain. The spatial density of large basins (D greater than or equal to 500 km) on Mercury is lower than that on the Moon. Morphological characteristics of basins on Mercury suggest that on average they are more degraded than lunar basins. These observations are consistent with more efficient modification, degradation, and obliteration of the largest basins on Mercury than on the Moon. This distinction may be a result of differences in the basin formation process (producing fewer rings), greater relaxation of topography after basin formation (subduing relief), and/or higher rates of volcanism during the period of heavy bombardment on Mercury compared to the Moon (burying basin rings and interiors).

  10. Impacts and Ophiolites: A Way to Recognize Large Terrestrial Impact Basins?

    Science.gov (United States)

    Olds, E. P.

    2015-12-01

    That Chicxulub Crater is located on ~35 km thick continental crust is apparently inconsistent with oceanic crustal/upper mantle geochemical signatures detected globally in the KT boundary impact layer [1-5 and unpublished Cr isotope data from the Yin lab at UC Davis] since introduction of the Alvarez hypothesis [6]. Apparent excavation and ejection of mafic/ultramafic target rock by the KT boundary impact might imply an additional KT impact site involving oceanic lithosphere. We speculate: 1) The Greater Antilles island chain ophiolite belt marks the rim of a ~700 km diameter impact basin, deformed and dismembered from an originally circular form by at least 50 million years of left lateral shear on the North American-Caribbean transform plate boundary; 2) Other ophiolite segments may similarly mark rims of large impact basins deformed to greater or lesser extent by, and serving as strain markers for, relative plate motions over geologic time; 3) The Greater Antilles/Chicxulub and Sulu Sea Basin/Spratly Island cases may constitute doublet craters of similar size ratio and separation distance; 4) Plate boundaries may be formed or modified by such impacts. Problems include: 1) The KT fireball layer should be tens of cm thick rather than a few mm thick [8-9]; 2) Impact basins of this size/scale are not expected in the Phanerozoic/Proterozoic [10]; References: [1] DePaolo D. J. et al. 1983. EPSL 64:356-373. [2] Hildebrand A. R. and Boynton W. V. 1988, LPI Contributions 673:78-79. [3] Hildebrand A. R. and Boynton W. V.. 1990. Science 248:843-847. [4] Montanari A. et al. 1983. Geology 11:668. [5] Bohor B. F. et al. 1989. Meteoritics 24:253. [6] Alvarez L. W. et al. 1980 Science 208:1095-1108. [7][8] Grieve R.A.F. and Cintala M.J. 1992 Meteoritics 27: 526-538. [9] Pierazzo E. et al. 1997 Icarus 127/2:408-423. [10] Ivanov B.A. et al. 2002 Asteroids III 89-101

  11. The Formation of Lunar Impact Basins: Observational Constraints from LRO Datasets and Comparisons with Models

    Science.gov (United States)

    Baker, D. M. H.; Head, J. W., III

    2016-12-01

    Impact basins provide windows into the subsurface and through time on a planetary body. However, meaningful geologic interpretations rely on a detailed understanding of their formation and the origin of basin materials. Data from the Lunar Reconnaissance Orbiter (LRO) have been critical to advancing our understanding of the formation of impact basins. We present a number of recent observations, including measurements of basin morphometry, mineralogy, and gravity anomalies, which provide a framework for constraining current formation models. Image data from the LRO Wide Angle Camera (WAC) and altimetry data from the Lunar Orbiter Laser Altimeter (LOLA) were used to refine the recognition of both fresh and degraded impact basins, including their ring structures. Analyses of gravity anomalies from the GRAIL mission show that mantle uplifts confined within the inner basin rings are characteristics that basins acquire from the onset. We used LOLA data to also make new measurements of basin morphometry. Small basins possessing two concentric rings ("peak-ring basins") have unique topographic signatures, consisting of inner depressions bounded by a peak ring and a higher annulus that grades to steeper wall material. LRO Narrow Angle Camera (NAC) images and Diviner rock abundance maps were used to identify boulder-rich outcrops in basin rings, which focused mineralogical analyses using Moon Mineralogy Mapper hyperspectral data. Crystalline plagioclase and candidate shock plagioclase outcrops were found to be abundant within basins of all sizes. These observations combined with crater scaling laws and lunar crustal thickness constrain the depth of origin of basin peak rings to be near the maximum depth of excavation. Comparisons between iSALE numerical models and observations show important consistencies and inconsistencies that can help to refine current models. In particular, improvements in the match between observed and modeled morphometry of craters transitional

  12. Benthic disturbance and impact experiments in the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.; Nath, B.N.; Valsangkar, A.B.; Parthiban, G.; Sivakholundu, K.M.; Walker, G.A.

    As a part of the Environmental Impact Assessment studies for nodule mining, a long-term program has been initiated in the Central Indian Basin. Multidisciplinary studies on geological, biological, physical and chemical parameters were carried out...

  13. Ocean Basin Impact of Ambient Noise on Marine Mammal Detectability, Distribution, and Acoustic Communication

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Ocean Basin Impact of Ambient Noise on Marine Mammal ... mammal acoustic communication and signal detection. How short term variability and long term changes of ocean basin acoustics impact signal detection...signal detection as it relates to marine mammal active acoustic space and acoustic communication. This work increases the spatial range and time scale

  14. Numerical modeling of the formation and structure of the Orientale impact basin

    Science.gov (United States)

    Potter, Ross W. K.; Kring, David A.; Collins, Gareth S.; Kiefer, Walter S.; McGovern, Patrick J.

    2013-05-01

    The Orientale impact basin is the youngest and best-preserved lunar multi-ring basin and has, thus, been the focus of studies investigating basin-forming processes and final structures. A consensus about how multi-ring basins form, however, remains elusive. Here we numerically model the Orientale basin-forming impact with the aim of resolving some of the uncertainties associated with this basin. By using two thermal profiles estimating lunar conditions at the time of Orientale's formation and constraining the numerical models with crustal structures inferred from gravity data, we provide estimates for Orientale's impact energy (2-9 × 1025 J), impactor size (50-80 km diameter), transient crater size (˜320-480 km), excavation depth (40-55 km), and impact melt volume (˜106 km3). We also analyze the distribution and deformation of target material and compare our model results and Orientale observations with the Chicxulub crater to investigate similarities between these two impact structures.

  15. Impact of Climate Change on Hydrologic Extremes in the Upper Basin of the Yellow River Basin of China

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2016-01-01

    Full Text Available To reveal the revolution law of hydrologic extremes in the next 50 years and analyze the impact of climate change on hydrologic extremes, the following main works were carried on: firstly, the long duration (15 d, 30 d, and 60 d rainfall extremes according to observed time-series and forecast time-series by dynamical climate model product (BCC-CSM-1.1 were deduced, respectively, on the basis that the quantitative estimation of the impact of climate change on rainfall extremes was conducted; secondly, the SWAT model was used to deduce design flood with the input of design rainfall for the next 50 years. On this basis, quantitative estimation of the impact of climate change on long duration flood volume extremes was conducted. It indicates that (1 the value of long duration rainfall extremes for given probabilities (1%, 2%, 5%, and 10% of the Tangnaihai basin will rise with slight increasing rate from 1% to 6% in the next 50 years and (2 long duration flood volume extremes of given probabilities of the Tangnaihai basin will rise with slight increasing rate from 1% to 6% in the next 50 years. The conclusions may provide technical supports for basin level planning of flood control and hydropower production.

  16. Lunar Impact Basins: Stratigraphy, Sequence and Ages from Superposed Impact Crater Populations Measured from Lunar Orbiter Laser Altimeter (LOLA) Data

    Science.gov (United States)

    Fassett, C. I.; Head, J. W.; Kadish, S. J.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2012-01-01

    Impact basin formation is a fundamental process in the evolution of the Moon and records the history of impactors in the early solar system. In order to assess the stratigraphy, sequence, and ages of impact basins and the impactor population as a function of time, we have used topography from the Lunar Orbiter Laser Altimeter (LOLA) on the Lunar Reconnaissance Orbiter (LRO) to measure the superposed impact crater size-frequency distributions for 30 lunar basins (D = 300 km). These data generally support the widely used Wilhelms sequence of lunar basins, although we find significantly higher densities of superposed craters on many lunar basins than derived by Wilhelms (50% higher densities). Our data also provide new insight into the timing of the transition between distinct crater populations characteristic of ancient and young lunar terrains. The transition from a lunar impact flux dominated by Population 1 to Population 2 occurred before the mid-Nectarian. This is before the end of the period of rapid cratering, and potentially before the end of the hypothesized Late Heavy Bombardment. LOLA-derived crater densities also suggest that many Pre-Nectarian basins, such as South Pole-Aitken, have been cratered to saturation equilibrium. Finally, both crater counts and stratigraphic observations based on LOLA data are applicable to specific basin stratigraphic problems of interest; for example, using these data, we suggest that Serenitatis is older than Nectaris, and Humboldtianum is younger than Crisium. Sample return missions to specific basins can anchor these measurements to a Pre-Imbrian absolute chronology.

  17. Pulling Marbles from a Bag: Deducing the Regional Impact History of the SPA Basin from Impact Melt Rocks

    Science.gov (United States)

    Cohen, Barbara A.; Coker, R. F.

    2009-01-01

    The South Pole-Aitken (SPA) basin is an important target for absolute age-dating. Vertical and lateral impact mixing ensures that regolith within SPA will contain rock fragments from SPA itself, local impact craters, and faraway giant basins. About 20% of the regolith at any given site is foreign [1, 2], but much of this material will be cold ejecta, not impact melt. We calculated the fraction of contributed impact melt using scaling laws to estimate the amount and provenance of impact melt, demonstrating that SPA melt is the dominant impact melt rock (>70%) likely to be present. We also constructed a statistical model to illustrate how many randomly-selected impact-melt fragments would need to be dated, and with what accuracy, to confidently reproduce the impact history of a site. A detailed impact history becomes recognizable after a few hundred to a thousand randomly-selected marbles, however, it will be useful to have more information (e.g. compositional, mineralogical, remote sensing) to group fragments. These exercises show that SPA melt has a high probability of being present in a scoop sample and that dating of a few hundred to a thousand impact-melt fragments will yield the impact history of the SPA basin.

  18. Assessment of basin-scale hydrologic impacts of CO2 sequestration, Illinois basin

    Science.gov (United States)

    Person, M.; Banerjee, A.; Rupp, J.; Medina, C.; Lichtner, P.; Gable, C.; Pawar, R.; Celia, M.; McIntosh, J.; Bense, V.

    2010-01-01

    Idealized, basin-scale sharp-interface models of CO2 injection were constructed for the Illinois basin. Porosity and permeability were decreased with depth within the Mount Simon Formation. Eau Claire confining unit porosity and permeability were kept fixed. We used 726 injection wells located near 42 power plants to deliver 80 million metric tons of CO2/year. After 100 years of continuous injection, deviatoric fluid pressures varied between 5.6 and 18 MPa across central and southern part of the Illinois basin. Maximum deviatoric pressure reached about 50% of lithostatic levels to the south. The pressure disturbance (>0.03 MPa) propagated 10-25 km away from the injection wells resulting in significant well-well pressure interference. These findings are consistent with single-phase analytical solutions of injection. The radial footprint of the CO2 plume at each well was only 0.5-2 km after 100 years of injection. Net lateral brine displacement was insignificant due to increasing radial distance from injection well and leakage across the Eau Claire confining unit. On geologic time scales CO2 would migrate northward at a rate of about 6 m/1000 years. Because of paleo-seismic events in this region (M5.5-M7.5), care should be taken to avoid high pore pressures in the southern Illinois basin. ?? 2010 Elsevier Ltd.

  19. Chicxulub multiring impact basin - Size and other characteristics derived from gravity analysis

    Science.gov (United States)

    Sharpton, Virgil L.; Burke, Kevin; Camargo-Zanoguera, Antonio; Hall, Stuart A.; Lee, D. S.; Marin, Luis E.; Suarez-Reynoso, Gerardo; Quezada-Muneton, Juan M.; Spudis, Paul D.; Urrutia-Fucugauchi, Jaime

    1993-01-01

    The buried Chicxulub impact structure in Mexico, which is linked to the Cretaceous-Tertiary (K-T) boundary layer, may be significantly larger than previously suspected. Reprocessed gravity data over Northern Yucatan reveal three major rings and parts of a fourth ring, spaced similarly to those observed at multiring impact basins on other planets. The outer ring, probably corresponding to the basin's topographic rim, is almost 300 kilometers in diameter, indicating that Chicxulub may be one of the largest impact structures produced in the inner solar system since the period of early bombardment ended nearly 4 billion years ago.

  20. Chicxulub multiring impact basin: size and other characteristics derived from gravity analysis.

    Science.gov (United States)

    Sharpton, V L; Burke, K; Camargo-Zanoguera, A; Hall, S A; Lee, D S; Marín, L E; Suáarez-Reynoso, G; Quezada-Muñeton, J M; Spudis, P D; Urrutia-Fucugauchi, J

    1993-09-17

    The buried Chicxulub impact structure in Mexico, which is linked to the Cretaceous- Tertiary (K-T) boundary layer, may be significantly larger than previously suspected. Reprocessed gravity data over Northern Yucatan reveal three major rings and parts of a fourth ring, spaced similarly to those observed at multiring impact basins on other planets. The outer ring, probably corresponding to the basin's topographic rim, is almost 300 kilometers in diameter, indicating that Chicxulub may be one of the largest impact structures produced in the inner solar system since the period of early bombardment ended nearly 4 billion years ago.

  1. Quantification of Climate Changes and Human Activities That Impact Runoff in the Taihu Lake Basin, China

    OpenAIRE

    Dingzhi Peng; Linghua Qiu; Jing Fang; Zhongyuan Zhang

    2016-01-01

    Although a fragile climate region, the Taihu Lake Basin is among the most developed regions in China and is subjected to intense anthropogenic interference. In this basin, water resources encounter major challenges (e.g., floods, typhoons, and water pollution). In this study, the impacts of climate changes and human activities on hydrological processes were estimated to aid water resource management in developed regions in China. The Mann-Kendall test and cumulative anomaly curve were applied...

  2. Human impacts on river ice regime in the Carpathian Basin

    Science.gov (United States)

    Takács, Katalin; Nagy, Balázs; Kern, Zoltán

    2014-05-01

    examples from the Carpathian Basin represent some of the most common human impacts (engineering regulation, hydropower usage, water pollution), disturbing natural river ice regimes of mid-latitude rivers with densely populated or dynamically growing urban areas along their courses. In addition simple tests are also introduced to detect not only the climatic, but also the effect of anthropogenic impacts on river ice regime. As a result of river regulation on River Danube at Budapest a vanishing trend in river ice phenomena could be detected in the Danube records. The average ice-affected season shortened from 40 to 27 days, the average ice-covered season reduced greatly, from 27 to 7 days. In historical times the ice jams on the River Danube caused many times ice floods. The relative frequency of the break-up jam also decreased; moreover no ice flood occurred over the past 50 years. The changes due to hydropower usage are different upstream and downstream to the damming along the river. On Raba River upstream of the Nick dam at Ragyogóhíd, the ice-affected and ice-covered seasons were lengthened by 4 and 9 days, in contrast, downstream of the dam, the length of the ice-covered season was shortened by 7 days, and the number of ice-affected days decreased by 8 days at Árpás. During the observation period at Budapest on Danube River, the temperature requirements for river ice phenomena occurrence changed. Nowadays, much lower temperatures are needed to create the same ice phenomena compared to the start of the observations. For ice appearance, the mean winter air temperature requirements decreased from +2.39 °C to +1.71 °C. This investigation focused on anthropogenic effects on river ice regime, eliminating the impact of climatic conditions. Different forms of anthropogenic effects cause in most cases, a shorter length of ice-affected seasons and decreasing frequency of ice phenomena occurrence. Rising winter temperatures result the same changes in river ice regime

  3. GRAIL Gravity Observations of the Transition from Complex Crater to Peak-Ring Basin on the Moon: Implications for Crustal Structure and Impact Basin Formation

    Science.gov (United States)

    Baker, David M. H.; Head, James W.; Phillips, Roger J.; Neumann, Gregory A.; Bierson, Carver J.; Smith, David E.; Zuber, Maria T.

    2017-01-01

    High-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) mission provide the opportunity to analyze the detailed gravity and crustal structure of impact features in the morphological transition from complex craters to peak-ring basins on the Moon. We calculate average radial profiles for free-air anomalies and Bouguer anomalies for peak-ring basins, proto-basins, and the largest complex craters. Complex craters and proto-basins have free-air anomalies that are positively correlated with surface topography, unlike the prominent lunar mascons (positive free-air anomalies in areas of low elevation) associated with large basins. The Bouguer gravity anomaly profiles of complex craters are highly irregular, with central positive anomalies that are generally absent or not clearly tied to interior morphology. In contrast, gravity profiles for peak-ring basins (approx. 200 km to 580 km) are much more regular and are highly correlated with surface morphology. A central positive Bouguer anomaly is confined within the peak ring and a negative Bouguer anomaly annulus extends from the edge of the positive anomaly outward to about the rim crest. A number of degraded basins lacking interior peak rings have diameters and gravity patterns similar to those of well-preserved peak-ring basins. If these structures represent degraded peak-ring basins, the number of peak-ring basins on the Moon would increase by more than a factor of two to 34. The gravity anomalies within basins are interpreted to be due to uplift of the mantle confined within the peak ring and an annulus of thickened crust between the peak ring and rim crest. We hypothesize that mantle uplift is influenced by interaction between the transient cavity and the mantle. Further, mascon formation is generally disconnected from the number of basin rings formed and occurs over a wide range of basin sizes. These observations have important implications for models of basin and mascon formation on the

  4. Impacts of Climate Change on Water and Agricultural Production in Ten Large River Basins in China

    Institute of Scientific and Technical Information of China (English)

    WANG Jin-xia; HUANG Ji-kun; YAN Ting-ting

    2013-01-01

    The overall goal of this paper is to examine impacts of climate change on water supply and demand balance and their consequences on agricultural production in ten river basins in China. To realize this goal, China Water Simulation Model (CWSM) is used to analyze three alternative climate scenarios (A1B, A2 and B2). The results show that the impacts of climate change on water supply and demand balance differ largely among alternative scenarios. While significant impacts of climate change on water balance will occur under the A1B scenario, the impacts of climate change under the A2 and B2 scenarios will be marginal. Under the A1B scenario, the water shortage in the river basins located in the northern China will become more serious, particularly in Liaohe and Haihe river basins, but the other river basins in the southern China will improve their water balance situations. Despite larger impacts of climate change on water balance in the northern China, its impacts on total crops’ production will be moderate if farmers would be able to reallocate water among crops and adjust irrigated and rainfed land. The paper concludes with some policy implications.

  5. Multi-basin, Multi-sector Drought Economic Impact Model in Python: Development and Applications

    Science.gov (United States)

    Gutenson, J. L.; Zhu, L.; Ernest, A. N. S.; Oubeidillah, A.; Bearden, B.; Johnson, T. G.

    2015-12-01

    Drought is one of the most economically disastrous natural hazards, one whose impacts are exacerbated by the lack of abrupt onset and offset that define tornados and hurricanes. In the United States, about 30 billion dollars losses is caused by drought in 2012, resulting in widespread economic impacts for societies, industries, agriculture, and recreation. And in California, the drought cost statewide economic losses about 2.2 billion, with a total loss of 17,100 seasonal and part-time jobs. Driven by a variety of factors including climate change, population growth, increased water demands, alteration to land cover, drought occurs widely all over the world. Drought economic consequence assessment tool are greatly needed to allow decision makers and stakeholders to anticipate and manage effectively. In this study, current drought economic impact modeling methods were reviewed. Most of these models only deal with the impact in the agricultural sector with a focus on a single basin; few of these models analyze long term impact. However, drought impacts are rarely restricted to basin boundaries, and cascading economic impacts are likely to be significant. A holistic approach to multi-basin, multi-sector drought economic impact assessment is needed.In this work, we developed a new model for drought economic impact assessment, Drought Economic Impact Model in Python (PyDEM). This model classified all business establishments into thirteen categories based on NAICS, and using a continuous dynamic social accounting matrix approach, coupled with calculation of the indirect consequences for the local and regional economies and the various resilience. In addition, Environmental Policy Integrated Climate model was combined for analyzing drought caused soil erosion together with agriculture production, and then the long term impacts of drought were achieved. A visible output of this model was presented in GIS. In this presentation, Choctawhatchee-Pea-Yellow River Basins, Alabama

  6. The nature and impact of climate change in the Challenge Program on Water and Food (CPWF) basins

    OpenAIRE

    Mulligan, M.; Fisher, M.; Sharma, B; Xu, Z. X.; Ringler, C.; Mahé, Gil; Jarvis, A.; Ramirez, J.; Clanet, Jean-Charles; Ogilvie, Andrew; Ahmad, M.

    2011-01-01

    In this article the authors assess the potential impacts of projected climate change on water, livelihoods and food security in the Basin Focal Projet basins. The authors consider expected change within the context of recently observed climate variability in the basins to better understand the potential impact of expected change and the options available for adaptation. They use multi-global circulation model climate projections for the AR4 SRES A2a scenario, downscaled and extracted for each...

  7. Early impact basins and the onset of plate tectonics. Ph.D. Thesis - Maryland Univ.

    Science.gov (United States)

    Frey, H.

    1977-01-01

    The fundamental crustal dichotomy of the Earth (high and low density crust) was established nearly 4 billion years ago. Therefore, subductable crust was concentrated at the surface of the Earth very early in its history, making possible an early onset for plate tectonics. Simple thermal history calculations spanning 1 billion years show that the basin forming impact thins the lithosphere by at least 25%, and increases the sublithosphere thermal gradients by roughly 20%. The corresponding increase in convective heat transport, combined with the highly fractured nature of the thinned basin lithosphere, suggest that lithospheric breakup or rifting occurred shortly after the formation of the basins. Conditions appropriate for early rifting persisted from some 100,000,000 years following impact. We suggest a very early stage of high temperature, fast spreading "microplate" tectonics, originating before 3.5 billion years ago, and gradually stabilizing over the Archaean into more modern large plate or Wilson Cycle tectonics.

  8. Lunar impact basins and crustal heterogeneity - New western limb and far side data from Galileo

    Science.gov (United States)

    Belton, Michael J. S.; Head, James W., III; Pieters, Carle M.; Greeley, Ronald; Mcewen, Alfred S.; Neukum, Gerhard; Klaasen, Kenneth P.; Anger, Clifford D.; Carr, Michael H.; Chapman, Clark R.

    1992-01-01

    Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale terrain that consisted of both highland materials and relatively large expanses of ancient mare basalts. The inside of the far side South Pole-Aitken basin (greater than 2000 kilometers in diameter) has low albedo, red color, and a relatively high abundance of iron- and magnesium-rich materials. These features suggest that the impact may have penetrated into the deep crust or lunar mantle or that the basin contains ancient mare basalts that were later covered by highlands ejecta.

  9. Bias-correction and Spatial Disaggregation for Climate Change Impact Assessments at a basin scale

    Science.gov (United States)

    Nyunt, Cho; Koike, Toshio; Yamamoto, Akio; Nemoto, Toshihoro; Kitsuregawa, Masaru

    2013-04-01

    Basin-scale climate change impact studies mainly rely on general circulation models (GCMs) comprising the related emission scenarios. Realistic and reliable data from GCM is crucial for national scale or basin scale impact and vulnerability assessments to build safety society under climate change. However, GCM fail to simulate regional climate features due to the imprecise parameterization schemes in atmospheric physics and coarse resolution scale. This study describes how to exclude some unsatisfactory GCMs with respect to focused basin, how to minimize the biases of GCM precipitation through statistical bias correction and how to cover spatial disaggregation scheme, a kind of downscaling, within in a basin. GCMs rejection is based on the regional climate features of seasonal evolution as a bench mark and mainly depends on spatial correlation and root mean square error of precipitation and atmospheric variables over the target region. Global Precipitation Climatology Project (GPCP) and Japanese 25-uear Reanalysis Project (JRA-25) are specified as references in figuring spatial pattern and error of GCM. Statistical bias-correction scheme comprises improvements of three main flaws of GCM precipitation such as low intensity drizzled rain days with no dry day, underestimation of heavy rainfall and inter-annual variability of local climate. Biases of heavy rainfall are conducted by generalized Pareto distribution (GPD) fitting over a peak over threshold series. Frequency of rain day error is fixed by rank order statistics and seasonal variation problem is solved by using a gamma distribution fitting in each month against insi-tu stations vs. corresponding GCM grids. By implementing the proposed bias-correction technique to all insi-tu stations and their respective GCM grid, an easy and effective downscaling process for impact studies at the basin scale is accomplished. The proposed method have been examined its applicability to some of the basins in various climate

  10. The formation of peak-ring basins: Working hypotheses and path forward in using observations to constrain models of impact-basin formation

    Science.gov (United States)

    Baker, David M. H.; Head, James W.; Collins, Gareth S.; Potter, Ross W. K.

    2016-07-01

    Impact basins provide windows into the crustal structure and stratigraphy of planetary bodies; however, interpreting the stratigraphic origin of basin materials requires an understanding of the processes controlling basin formation and morphology. Peak-ring basins (exhibiting a rim crest and single interior ring of peaks) provide important insight into the basin-formation process, as they are transitional between complex craters with central peaks and larger multi-ring basins. New image and altimetry data from the Lunar Reconnaissance Orbiter as well as a suite of remote sensing datasets have permitted a reassessment of the origin of lunar peak-ring basins. We synthesize morphometric, spectroscopic, and gravity observations of lunar peak-ring basins and describe two working hypotheses for the formation of peak rings that involve interactions between inward collapsing walls of the transient cavity and large central uplifts of the crust and mantle. Major facets of our observations are then compared and discussed in the context of numerical simulations of peak-ring basin formation in order to plot a course for future model refinement and development.

  11. Basin-forming impacts on Mars and the coupled thermal evolution of the interior

    Science.gov (United States)

    Arkani-Hamed, J.; Roberts, J. H.

    2015-12-01

    The youngest of the Noachian giant impact basins on Mars, are either weakly magnetized or completely demagnetized, indicating that a global magnetic field was not present and that a core dynamo was not operating at the time those basins formed. Shock heating from this sequence of basin-forming impacts modified the pattern of mantle convection. The heating produced by the eight largest impacts (Acidalia, Amazonis, Ares, Chryse, Daedalia, Hellas, Scopolus, and Utopia) penetrates below the core-mantle boundary (CMB). Here, we extend previous workon coupled thermal evolution into 3D, in order to accurately model the spatial relationship between impact basins. At the time of each impact we introduce a temperature perturbation resulting from shock heating into the core and mantle. Stratification of the core occurs very quickly compared to mantle dynamics, and we horizontally average the temperature in the core.We model mantle convection using the 3D finite element code CitcomS, and the thermal evolution of the core using a 1D parameterization.Each impact alters the pattern of mantle dynamics and a significant amount of impact melt is produced in the near surface. However, only the outermost part of the core is affected; the inner core temperature is still adiabatic. Immediately following the impact, the inner core may remain convective. The top of the core will cool by conduction into the deeper core faster than across the CMB, deepening the zone of stable stratification. Further core cooling results in formation of a convecting zone at the top of the core that propagates downwards as the thermal gradient becomes adiabatic at greater depths. Our goal is to obtain a better estimate of the time scale for restoration of post-impact core dynamo activity. Because the disappearance of the magnetic field exposes the early atmosphere to solar wind activity, constraining the history of the dynamo is critical for understanding climate evolution and habitability of the surface.

  12. Statistical Bias Correction scheme for climate change impact assessment at a basin scale

    Science.gov (United States)

    Nyunt, C. T.

    2013-12-01

    Global climate models (GCMs) are the primary tool for understanding how the global climate may change in the future. GCM precipitation is characterized by underestimation of heavy precipitation, frequency errors by low intensity with long drizzle rain days and fail to catch the inter-seasonal change compared to the ground data. This study focus on the basin scale climate change impact study and we proposed the method for the multi model (GCMs) selection method together with the statistical bias correction method which cover the major deficiencies of GCM biases for climate change impact study at the basin level. The proposed method had been tested its applicability in the various river basin under different climate such as semiarid region in Tunisia, tropical monsoonal climate in Philippines and temperate humid region in Japan. It performed well enough for the climate change impact study in the basin scale and it can catch the point scale and basin scale climatology precipitation very well during the historical simulation. We found the GCM simulation during baiu season dissipate the baiu activity more earlier than the actual one when compared to the in-situ station data in Japan. For that case, the proposed bias correction performed in each season to reduce the bias of GCM for the impact study. The proposed bias correction method is still tested in different river basin in the world to check it applicability and now under developing as the web interface as the handy and efficient tool for the end users from the different parts of the world.

  13. GRAIL gravity observations of the transition from complex crater to peak-ring basin on the Moon: Implications for crustal structure and impact basin formation

    Science.gov (United States)

    Baker, David M. H.; Head, James W.; Phillips, Roger J.; Neumann, Gregory A.; Bierson, Carver J.; Smith, David E.; Zuber, Maria T.

    2017-08-01

    High-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) mission provide the opportunity to analyze the detailed gravity and crustal structure of impact features in the morphological transition from complex craters to peak-ring basins on the Moon. We calculate average radial profiles of free-air anomalies and Bouguer anomalies for peak-ring basins, protobasins, and the largest complex craters. Complex craters and protobasins have free-air anomalies that are positively correlated with surface topography, unlike the prominent lunar mascons (positive free-air anomalies in areas of low elevation) associated with large basins. The Bouguer gravity anomaly profiles of complex craters are highly irregular, with central positive anomalies that are generally absent or not clearly tied to interior morphology. In contrast, gravity profiles for peak-ring basins (∼200 km to 580 km) are much more regular and are highly correlated with surface morphology. A central positive Bouguer anomaly is confined within the peak ring and a negative Bouguer anomaly annulus extends from the edge of the positive anomaly outward to about the rim crest. A number of degraded basins lacking interior peak rings have diameters and gravity patterns similar to those of well-preserved peak-ring basins. If these structures represent degraded peak-ring basins, the number of peak-ring basins on the Moon would increase by more than a factor of two to 34. The gravity anomalies within basins are interpreted to be due to uplift of the mantle confined within the peak ring and an annulus of thickened crust between the peak ring and rim crest. We hypothesize that mantle uplift is influenced by interaction between the transient cavity and the mantle. Further, mascon formation is generally disconnected from the number of basin rings formed and occurs over a wide range of basin sizes. These observations have important implications for models of basin and mascon formation on the Moon

  14. SWAT-simulated hydrological impact of land-use change in the Zanjanrood basin, Northwest Iran

    NARCIS (Netherlands)

    Ghaffari, G.; Ghodousi, J.; Ahmadi, H.; Keesstra, S.D.

    2010-01-01

    Understanding the impacts of land-use changes on hydrology at the watershed scale can facilitate development of sustainable water resource strategies. This paper investigates the hydrological effects of land-use change in Zanjanrood basin, Iran. The water balance was simulated using the Soil and Wat

  15. The impact of global warming on the runoff in the Yangtze River Basin

    Science.gov (United States)

    Chen, Hua; Hu, Kang; Xu, Chongyu; Hou, Yukun

    2016-04-01

    As the largest water system in China, the Yangtze River is important to China. The amount and distribution of water resources are a key impact factor to the ecology protection and the economy development in the Yangtze River basin. In this study, the impact of global warming on the runoff in the Yangtze River basin has been evaluated by coupling the GCMs (Global Climate Models) and a monthly water balance model. In the study hydro-meteorological data from 140 gauges and hydrological data from 20 stations are used. The spatial-temporal changing trends of the runoff, precipitation and temperature are analyzed by using the Mann-Kendall method during the period of 1960-2015. A bias correction method and a statistical downscaling method (MC-SVM, Markov Chain-Support Vector Machine) are used to deal with the temperature and precipitation from a regional climate model and their performances have been evaluated. To simulate the runoff in the basin, the two-parameter monthly water balance model is calibrated and validated in the 20 sub-basins. The CMIP5 projections downscaled from RCM are used as inputs into the water balance model to predict the future possible changes on runoff under global warming. The results will be helpful to maintain the health of the water ecology and the sustainability of water resources utilization in the basin.

  16. Modeling the Impact of Climate Change on Water Resources in the Senegal River Basin

    Science.gov (United States)

    Mbaye, M. L.

    2015-12-01

    In this study we assess the impact of climate change on water resources by using uncorrected and bias corrected data from the regional climate model REMO simulations over the Senegal River Basin. Both simulations were used as input of the Max Planck Institute for Meteorology - Hydrological Model over the Upper Senegal Basin.Applying the bias correction simulations of present day climate (1971-2000) substantially improved for both temporal and spatial variations of the analyzed climate parameters (precipitation, temperature) when compared to observations and independent station data. Additionally, the bias corrected input give better representation of the mean river flow, the low flows (10th percentile) and the high flows (90thpercentile) at the outlet of the USB.For the future, the regional climate model projections for precipitation show a general decrease by the end of 21stcentury (2071-2100) for both scenarios RCP4.5 and RCP8.5 and datasets in the majority of the basin, except the Guinean highlands where a slight increase is found. In case of the potential changes of the maximum consecutive number of dry days and wet days, the northern basin is likely to face the most pronounced increase of dry days and decrease of wet days, although slight increase of heavy rainfall is found with similar spatial patterns in both data. Furthermore, a general temperature increase is projected over the entire basin for both scenarios, but more pronounced under the RCP8.5 scenario. Warm night's percent is found to be higher than warm day's percent. As for the potential changes of the basin's hydrology, a general decrease of river discharge, runoff, actual evapotranspiration, soil moisture is found under RCP4.5 and RCP8.5 in all simulations. The decrease is higher under RCP8.5 with uncorrected data in the northern basin. However, there are some localized increases of runoff in some parts of the basin. Furthermore, the available water resources are projected to substantially decrease

  17. Impact of climate change on vegetation dynamics in a West African river basin

    Science.gov (United States)

    Sawada, Y.; Koike, T.

    2012-12-01

    Future changes in terrestrial biomass distribution under climate change will have a tremendous impact on water availability and land productivity in arid and semi-arid regions. Assessment of future change of biomass distribution in the regional or the river basin scale is strongly needed. An eco-hydrological model that fully couples a dynamic vegetation model (DVM) with a distributed biosphere hydrological model is applied to multi-model assessment of climate change impact on vegetation dynamics in a West African river basin. In addition, a distributed and auto optimization system of parameters in DVM is developed to make it possible to model a diversity of phonologies of plants by using different parameters in the different model grids. The simple carbon cycle modeling in a distributed hydrological model shows reliable accuracy in simulating the seasonal cycle of vegetation on the river basin scale. Model outputs indicate that generally, an extension of dry season duration and surface air temperature rising caused by climate change may cause a dieback of vegetation in West Africa. However, we get different seasonal and spatial changes of leaf area index and different mechanisms of the degradation when we used different general circulation models' outputs as meteorological forcing of the eco-hydrological model. Therefore, multi-model analysis like this study is important to deliver meaningful information to the society because we can discuss the uncertainties of our prediction by this methodology. This study makes it possible to discuss the impact of future change of terrestrial biomass on climate and water resources in the regional or the river basin scale although we need further sophistications of the system. Performance of the eco-hydrological model (WEB-DHM+DVM) in Volta River Basin, with basin-averaged leaf area index from model (blue solid line) and AVHRR satellite-derived product (red rectangles).

  18. Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

    Institute of Scientific and Technical Information of China (English)

    CHEN; Junfeng; LI; Xiubin

    2005-01-01

    Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%-80%, while that of land cover changes only 20%.

  19. Investigation of Pollution from Land Based Sources and Activities and their Impacts on the Marine Environment: the Caroni River Basin

    OpenAIRE

    Gabbadon, P.; Banjoo, D.; Bullock, C; Norville, W.; Sookbir, S.; Lloyd, G.; Ragbirsingh, Y.; Juman, R.; Chin, X.; Souza, G.; Lall, R; Rambarath-Parasram, V.; O'Brien-Delpesh, C.

    2006-01-01

    "The Institute of Marine Affairs (IMA) is investigating the impacts of pollution from land-based sources and activities of the Caroni River Basin (CRB) on the marine environment... The project will investigate the types, sources, levels of pollution, fate of pollutants, and potential impacts on the marine environment. In addition, the project will investigate the impacts of physical alterations of habitats caused by land uses in the Caroni River Basin."

  20. Multi-model climate impact assessment and intercomparison for three large-scale river basins on three continents

    OpenAIRE

    Vetter, T.; Huang, S.; Aich, V.; Yang, T; X. Wang; Krysanova, V.; Hattermann, F.

    2015-01-01

    Climate change impacts on hydrological processes should be simulated for river basins using validated models and multiple climate scenarios in order to provide reliable results for stakeholders. In the last 10–15 years, climate impact assessment has been performed for many river basins worldwide using different climate scenarios and models. However, their results are hardly comparable, and do not allow one to create a full picture of impacts and uncertainties. Therefore, a s...

  1. Human Health Impact of Fluoride in Groundwater in the Chiang Mai Basin

    Science.gov (United States)

    Matsui, Y.; Takizawa, S.; Wattanachira, S.; Wongrueng, A.; Ibaraki, M.

    2005-12-01

    Chiang Mai Basin, in Northern Thailand, is known as a fluorotic area. Groundwater of the Chiang Mai Basin has been gradually replaced by contaminated surface water since the 1980's. People have been exposed to fluoride contaminated groundwater since that time. As a result, harmful health effects on dental and skeletal growth were observed in the 90's. These include dental and skeletal fluorosis. Dental fluorosis is characterized by yellow or white spots on teeth and pitting or mottled enamel, consequently causing the teeth to look unsightly. Skeletal fluorosis leads to changes in bone structure, making them extremely weak and brittle. The most severe form of this is known as ``crippling skeletal fluorosis,'' a condition that can cause immobility, muscle wasting, and neurological problems related to spinal cord compression. This study focuses on the problematic issue of the Chiang Mai Basin's groundwater from the viewpoint of fluoride occurrence and current health impacts. Chiang Mai and Lamphun Provinces comprise the Chiang Mai Basin. Fluoride rich granites or fluorite deposits are scattered across the mountainside of the Lamphun Province. Tropical savanna climate conditions with seasonal monsoons bring more than 1,000 mm of annual precipitation, which can prompt weathering of minerals containing fluoride. The Ping River dominates the Basin, and the main eastern tributary of the Ping River runs through the Lamphun Province. The Basin has geological units composed of lower semi-consolidated Tertiary fluvial and upper unconsolidated Quaternary alluvium deposits. The main aquifers are in the upper unconsolidated unit. High fluoride concentrations tend to be observed in the aquifer located in lower part of this unconsolidated unit. We have been investigating two areas in the Basin. These two locations are similar with respect to geological and hydrological settings. However, one area in which groundwater is Ca-bicarbonate dominant has a low fluoride occurrence

  2. Impact of Water Scarcity on the Fenhe River Basin and Mitigation Strategies

    Directory of Open Access Journals (Sweden)

    Weiwei Shao

    2017-01-01

    Full Text Available This study produced a drought map for the Fenhe River basin covering the period from 150 BC to 2012 using regional historical drought records. Based on meteorological and hydrological features, the characteristics and causes of water scarcity in the Fenhe River basin were examined, along with their impact on the national economy and ecological environment. The effects of water scarcity in the basin on the national economy were determined from agricultural, industrial, and domestic perspectives. The impact on aquatic ecosystems was ascertained through an evolution trend analysis of surface water systems, including rivers, wetlands, and slope ecosystems, and subterranean water systems, including groundwater and karst springs. As a result of these analyses, strategies are presented for coping with water scarcity in this basin, including engineering countermeasures, such as the construction of a water network in Shanxi, and the non-engineering approach of groundwater resource preservation. These comprehensive coping strategies are proposed with the aim of assisting the prevention and control of water scarcity in the arid and semi-arid areas of China.

  3. Assessment of climate change impact on water resources in the Upper Senegal basin

    Science.gov (United States)

    Lamine Mbaye, Mamadou; Hagemann, Stefan; Haensler, Andreas; Stacke, Tobias; Thierno Gaye, Amadou

    2015-04-01

    This study assesses the potential impacts of climate change on water resources and the effect of statistical bias correction on the projected climate change signal in hydrological variables over the Upper Senegal Basin (West Africa). Original and bias corrected climate data from the regional climate model REMO were used as input for the Max Planck Institute for Meteorology-Hydrology Model (MPI-HM) to simulate river discharge, runoff, soil moisture and evapotranspiration. The results during the historical period (1971-2000) show that using the bias corrected input yields a better representation of the mean river flow regimes and the 10th and 90th percentiles of river flow at the outlet of the Upper Senegal Basin (USB). The Nash-Sutcliffe efficiency coefficient is 0.92 using the bias corrected input, which demonstrates the ability of the model in simulating river flow. The percent bias of 3.88% indicates a slight overestimation of the river flow by the model using the corrected input. The evaluation demonstrates the ability of the bias correction and its necessity for the simulation of historical river regimes. As for the potential changes of hydrological variables by the end of 21st century (2071-2100), a general decrease of river discharge, runoff, actual evapotranspiration, soil moisture is found under two Representative Concentration Pathways (RCP4.5 and RCP8.5) in all simulations. The decrease is higher under RCP8.5 with uncorrected data in the northern basin. However, there are some localized increases in some parts of the basin (e.g Guinean Highlands). The projected climate change signal of these above variables has the same spatial pattern and tendency for the uncorrected and bias corrected data although the magnitude of the corrected signal is somewhat lower than that uncorrected. Furthermore, the available water resources are projected to substantially decrease by more than -50% in the majority of the basin (especially in driest and hottest northern basin

  4. The impact of land abandonment on species richness and abundance in the Mediterranean Basin

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Hui, Cang; Gaertner, Mirijam

    2014-01-01

    Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a metaanalysis of the effects of land abandonment on plant and animal...... species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales...... the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After...

  5. Impact of climate variations on Managed Aquifer Recharge infiltration basins.

    Science.gov (United States)

    Barquero, Felix; Stefan, Catalin

    2017-04-01

    KEYWORDS: Managed Aquifer Recharge, field scale infiltration unit, climatic conditions, numerical model Managed Aquifer Recharge (MAR) is a technique that is gaining more attention as a sustainable alternative for areas where water scarcity is increasing. Main concept relies on facilitating the vertical infiltration of a source of fresh water (river water, rainwater, reclaimed water, etc). The groundwater acts as storage of water for further use in the future, for example in times of water scarcity. In some MAR types the soil itself can be used even as a filter for the removal of specific organic and inorganic compounds. In order to promote the benefits of MAR in different zones of the globe with variable climate conditions, including the effects of climate change, a numerical model (HYDRUS 2D/3D) is being set up. Coupled with the model a field-scale rapid infiltration unit (4m x 5m x 1.5m) was constructed with the capacity to log different MAR key parameters in the soil (tension, water content, temperature and electrical conductivity) in space and time. These data will feed the model for its calibration using specific hydrogeological characteristics of the packing material and hydraulic characteristics of the infiltrated fluid. The unit is located in the city of Pirna (German), 200 m north from the Elbe River where the groundwater level varies seasonally between 6 and 9 m below the ground surface. Together with the field scale rapid infiltration unit, a set of multi-parametric sensors (measuring in time: water stage, electrical conductivity, dissolved oxygen and temperature) in six monitoring wells, located on the basin surroundings, were installed. The purpose of these sensors is to estimate, via tracer experiments, the time that the infiltrated water needed to reach the groundwater and the flow speed in which it travelled once it reached the saturated zone. Once calibrated, the model will be able to estimate the flow behaviour under variable climate conditions

  6. The Impacts of Climate Change on Hydrology and Water Resources in Zayandeh-Rood Basin - Iran

    Science.gov (United States)

    Abrishamchi, A.; Azaranfar, A.; Ghasemi, S.; Tajrishy, M.; Marino, M. A.; Abrishamchi, A.

    2007-12-01

    Increasing concentration of greenhouse gases may have significant consequences on the global climate. If climate change occurs, changes in temperature and precipitation may have profound impacts on hydrologic processes, water resources and water uses such as agriculture. In Zayandeh-River Basin of Iran, agriculture is an important economic activity and is the main water user. Climate change may exacerbate the already contentious water supply situation in the basin. This paper focuses on the impact of climate change on hydrology and water resources of Zayandeh-Rood river basin. GCM models do not have suitable spatial resolution for regional assessment, so GCM outputs should be downscaled to the regional scale. In this paper, statistical downscaling is used in two difference methods (probability and regression) for downscaling the CGCM2 model outputs under A2 and B2 scenarios for two periods: 2021-2050 (immediate future) and 2071-2100 (far future). Temperature and precipitation projections from the downscaled GCM outputs were used as inputs to the hydrologic model. To study the impact of climate change on the water resources in the basin, an operational model was used to simulate the operation of the Zayandeh-Rood reservoir under different hydrologic projections. Both scenarios showed similar increases in temperature while they have less agreement in the amount and rate of precipitation they projected. The results of this study also show that the water resources in the study area are sensitive to changes in temperature and precipitation projections. The reservoir simulations provide information on the timing and rate of changes expected in water supply. The methodology developed can be used to predict the impacts of new or updated predictions of climate change. Vulnerability to climate change may be characterized as a function of three components: sensitivity, exposure, and adaptive capacity. In this study, only the first component and infrastructure as an indicator

  7. Anticipation of drought impacts in the Ebro basin using remote sensing data

    Science.gov (United States)

    Lines, Clara; Werner, Micha; Bastiaanssen, Wim

    2017-04-01

    For an effective mitigation of drought impacts, managers should be able to detect drought processes that will lead to impacts with enough anticipation to allow the necessary measures to be undertaken. Drought indicators and thresholds are commonly used to detect and classify drought conditions and trigger mitigation actions. However, the indicators and thresholds selected as triggers are only rarely connected to the specific impacts that need to be avoided. The aim of this research is to identify global earth observation data sets that can anticipate drought impacts at basin scale and therefore be used as indicators of early stages of drought. The performance of a broad range of parameters was assessed in the Ebro basin for the period 2000-2012. These were the Standard Precipitation Index (SPI), the Normalized Difference Vegetation Index (NDVI), Evapotranspiration (ET), Soil Moisture (SM), Land Surface Temperature (LST), Gross Primary Production (GPP) and the in situ hydrologic indicators currently used in the basin. Since impact data at a suitable temporal and spatial scale was not available to be used as benchmark for the tests, a data set of drought and impact occurrence was compiled by a comprehensive review of local news records. In addition annual crop yield data was used as alternative benchmark data. Early signs of drought impact were detected up to 6 months in advance with respect to the impacts reported in the newspaper, with SPI, NDVI and ET showing the best correlation-anticipation relationships. SM and LST offer also good anticipation, but with weaker correlations, while GPP presents moderate positive correlations only for some of the rainfed areas. Although water levels and flows from in situ stations provided better anticipation than remote sensing indicators in most of the areas, correlations were found to be weaker. The indicators show a consistent behaviour with respect to the different levels of crop yield in rainfed areas among the analysed

  8. Impacts of climate change on hydro-meteorological drought over the Volta Basin, West Africa

    Science.gov (United States)

    Oguntunde, Philip G.; Abiodun, Babatunde J.; Lischeid, Gunnar

    2017-08-01

    This study examines the characteristics of drought in the Volta River Basin (VRB), investigates the influence of drought on the streamflow, and projects the impacts of future climate change on the drought. A combination of observation data and regional climate simulations of past and future climates (1970-2013, 2046-2065, and 2081-2100) were analyzed for the study. The Standardized Precipitation Index (SPI) and Standardized Precipitation and Evapotranspiration (SPEI) were used to characterize drought while the Standardized Runoff Index (SRI) were used to quantify runoff. Results of the study show that the historical pattern of drought is generally consistent with previous studies over the Basin and most part of West Africa. RCA ensemble medians (RMED) give realistic simulations of drought characteristics and area extent over the Basin and the sub-catchments in the past climate. Generally, an increase in drought intensity and spatial extent are projected over VRB for SPEI and SPI, but the magnitude of increase is higher with SPEI than with SPI. Drought frequency (events per decade) may be magnified by a factor of 1.2 (2046-2065) to 1.6 (2081-2100) compared to the present day episodes in the basin. The coupling between streamflow and drought episodes was very strong (P < 0.05) for the 1-16-year band before the 1970 but showed strong correlation all through the time series period for the 4-8-years band. Runoff was highly sensitive to precipitation in the VRB and a 2-3 month time lag was found between drought indices and streamflow in the Volta River Basin. Results of this study may guide policymakers in planning how to minimize the negative impacts of future climate change that could have consequences on agriculture, water resources and energy supply.

  9. The Impact of Land Use Changes on Runoff of Taihu Lake Basin of China

    Science.gov (United States)

    Li, Hengpeng; Yang, Guishan; Diao, Yaqin; Li, Pengcheng

    2017-04-01

    Land use/cover changes play a role of "interface" linking human activities and environmental systems. Land use changes alter the hydrological characteristics of the land surface, and have significant impacts on hydrological cycle and water balance, leading to increasing flood disaster. Taihu lake basin is fastest on urbanization among the regions in the east part of China. Impacted by cities' fast expansion, the problem of storm flood disaster is very serious. In this study, land use information was extracted from 5-year's TM/ETM images of 1985, 1995, 2000, 2005 and 2010. A grid-based distributed hydrological model was applied to estimate Runoff response to land use changes by simulating the monthly and annual runoff using long-term rainfall records from 1980 to 2010. Results showed that rapid changes in land use was noted in Taihu Lake catchment, which is characterized by conversion of agricultural land to construction land. The share of construction land increased from 9.7% to 13.4% in 15 years (1985-2000) with the increased area of 1388 km2; In the following 2000-2010, the share of construction land increased from 13.4% to 24.2% with the increased area of 4038 km2. The land use changes during 1985-2000 resulted in an average increase of runoff by 4.37% in the whole Taihu Lake basin, approximately 6.46×108m3. The land use changes during 1985-2010 led to an average increase of runoff by 12.82% in the whole basin, around 18.99×108m3. Based on the analysis of rainfall variation in recent years in Taihu Lake basin, it is concluded that the increasing urban storm floods in Taihu Lake basin are closely related to the fast urbanization process.

  10. Life-cycle cost and impacts: alternatives for managing KE basin sludge

    Energy Technology Data Exchange (ETDEWEB)

    Alderman, C.J.

    1997-06-27

    This document presents the results of a life-cycle cost and impacts evaluation of alternatives for managing sludge that will be removed from the K Basins. The two basins are located in the 100-K Area of the Hanford Site. This evaluation was conducted by Fluor Daniel Hanford, Inc. (FDH) and its subcontractors to support decisions regarding the ultimate disposition of the sludge. The long-range plan for the Hanford Site calls for spent nuclear fuel (SNF), sludge, debris, and water to be removed from the K East (KE) and K West (KW) Basins. This activity will be conducted as a removal action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). The scope of the CERCLA action will be limited to removing the SNF, sludge, debris, and water from the basins and transferring them to authorized facilities for interim storage and/or treatment and disposal. The scope includes treating the sludge and water in the 100-K Area prior to the transfer. Alternatives for the removal action are evaluated in a CERCLA engineering evaluation/cost analysis (EE/CA) and include different methods for managing sludge from the KE Basins. The scope of the removal action does not include storing, treating, or disposing of the sludge once it is transferred to the receiving facility and the EE/CA does not evaluate those downstream activities. This life-cycle evaluation goes beyond the EE/CA and considers the full life-cycle costs and impacts of dispositioning sludge.

  11. Adaptive simulation of the impact of changes in land use on water resources in the lower Aswa basin

    Directory of Open Access Journals (Sweden)

    Martine Nyeko

    2013-03-01

    Full Text Available In the lower Aswa basin, Uganda, the changes in land use due to complex demographic and social economic factors are among the numerous challenges facing management of the limited water resources. The current study analysed the degree to which water yield in the Aswa basin could be changed by altering the vegetation cover (here considered to be agricultural use and forest at the basin and sub-basin level, and whether manipulation of vegetation cover can complement water resource management objectives in the study area. The distributed hydrological process Soil Water Assessment Tool (SWAT model was used to simulate the impact of the changes in vegetation cover on water balance. The impact was compared with the water balance simulated using the year 2001 as baseline. The results showed that: 37.5% afforestation at the basin scale can reduce water yield by 15.85%; using 53.7% of the land for agriculture can increase water yield by 27.6%, while a combination of 23.2% forest and 52% agriculture can increase water yield by 24.85%. The location of forest and agricultural land cover with respect to rainfall regime also indicated a notable impact on sub-basin water balance. In particular, afforestation in sub-basins receiving less than 900 mm annual rainfall considered as dry showed minimum change in surface runoff and net water yield, while in sub-basins receiving more than 900 mm annual rainfall afforestation showed notable change in water yield. In this way, afforestation in dry sub-basins can be used to offset the afforestation pressure in the wet sub-basin without altering the basin water balance.

  12. Quantification of Climate Changes and Human Activities That Impact Runoff in the Taihu Lake Basin, China

    Directory of Open Access Journals (Sweden)

    Dingzhi Peng

    2016-01-01

    Full Text Available Although a fragile climate region, the Taihu Lake Basin is among the most developed regions in China and is subjected to intense anthropogenic interference. In this basin, water resources encounter major challenges (e.g., floods, typhoons, and water pollution. In this study, the impacts of climate changes and human activities on hydrological processes were estimated to aid water resource management in developed regions in China. The Mann-Kendall test and cumulative anomaly curve were applied to detect the turning points in the runoff series. The year of 1982 divides the study period (1956~2008 into a baseline period (1956~1981 and a modified period (1982~2008. The double mass curve method and the hydrological sensitivity method based on the Budyko framework were applied to quantitatively attribute the runoff variation to climate changes and human activities. The results demonstrated that human activities are the dominant driving force of runoff variations in the basin, with a contribution of 83~89%; climate changes contributed to 11~17% of the variations. Moreover, the subregions of the basin indicated that humans severely disturbed the runoff variation, with contributions as high as 95~97%.

  13. Climate Change and its Impact on Water Resources in the Huai River Basin

    Institute of Scientific and Technical Information of China (English)

    ZUO Qiting; CHEN Yaobin; TAO Jie

    2012-01-01

    Rainfall and air temperature data from six meteorological stations above the Bengbu Sluice and hydrological and water resources evaluation data from the Bengbu Hydrological Station in the Huai River Basin from 1961 to 2008 are used to analyze the impact of changes in climatic factors on the amount of water resources in the Basin. There was a general trend of rise in its average annual air temperature, with the highest increase of 0.289℃/10a recorded at Bengbu in Anhui Province. Rising rainfall was mainly observed in the western part of the study area, while rainfall actually declined in the eastern part, i.e. the middle reaches of the Huai River. The Average rainfall in the study area was in a vaguely declining trend. In other words, the rainfall in the Basin is still much affected by natural fluctuations. On the whole, there was a trend of gradual decrease in the quantity of the Basin's water resources for the period under study. Water resources quantity is found to fall with decreasing rainfall and rising air temperature. Regression analysis is used to establish a mathematical model between water resources quantity and climatic factors (i.e. air temperature and rainfall) in order to explore the impact of climate change on water resources in the Basin. Moreover, various scenarios are set to quantitatively analyze the response of water resources to climate change. Sensitivity analysis shows that changes in rainfall have a much bigger impact on its water resources quantity than changes in its air temperature.

  14. Impact of climate change on sediment yield in the Mekong River basin: a case study of the Nam Ou basin, Lao PDR

    NARCIS (Netherlands)

    Shrestha, B.; Babel, M.S.; Maskey, S.; Van Griensven, A.; Uhlenbrook, S.; Green, A.; Akkharath, I.

    2013-01-01

    This paper evaluates the impact of climate change on sediment yield in the Nam Ou basin located in northern Laos. Future climate (temperature and precipitation) from four general circulation models (GCMs) that are found to perform well in the Mekong region and a regional circulation model (PRECIS) a

  15. Evaluation of climate change impact on Blue Nile Basin Cascade Reservoir operation – case study of proposed reservoirs in the Main Blue Nile River Basin, Ethiopia

    OpenAIRE

    2015-01-01

    This study mainly deals with evaluation of climate change impact on operation of the Blue Nile Basin Cascade Reservoir. To evaluate the impact of climate change, climate change scenarios of evapotranspiration and precipitation were developed for three periods. Output of ECHAM5 with RCM for the A1B emissions scenario were used to develop the future climate change scenarios. A hydrological model, HEC-HMS, was used to simulate current and future inflow volume to the reservoirs. The projected fut...

  16. The Impact of Heavy Rainfall in the Hydrological Regime of Suha River Basin in 2006

    Directory of Open Access Journals (Sweden)

    Tirnovan

    2014-10-01

    Full Text Available Recent climate changes mentioned in the Intergovernmental Panel for Climate Change (IPCC, 2013 report highlight the fact that in the past 50 years at the planetary level have occurred major changes in all climate components. In this regard the analysis of rainfall oscillations and of their impact on the hydric regime is particularly important, being witnessed in the surface and groundwater level variations. In the Suha River Basin, the year 2006 has been characterized by large rainfall quantities that have been generated, in particular, in June by persistent retrograde cyclonic activity (223 mm at Slătioara 3 hydrometric station, 269.1 mm at Gemenea 5 station, 271.6 mm at Valea lui Ion station and 351.8 mm at Stulpicani. On the main course of Suha, but especially on its tributaries (Gemenea and Slătioara have been recorded very high flow rates (5% and 2% insurance caused by the amounts of rainfall felt in a short time. To estimate the impact of rainfall on the Suha basin hydrological regime we used data collected by the Siret Basin Water Administration-Bacau, being analyzed the rainfall quantities, duration, intensity, tendency and effects.

  17. Impacts of Forecasted Climate Change on Snowpack, Glacier Recession, and Streamflow in the Nooksack River Basin

    Science.gov (United States)

    Murphy, R. D.; Mitchell, R. J.; Bandaragoda, C.; Grah, O. J.

    2015-12-01

    Like many watersheds in the North Cascades Mountain range, streamflow in the Nooksack River is strongly influenced by precipitation and snowmelt in the spring and glacial melt in the warmer summer months. With a maritime climate and a high relief basin with glacial ice (3400 hectares), the streamflow response in the Nooksack is sensitive to increases in temperature, thus forecasting the basins response to future climate is of vital importance for water resources planning purposes. The watershed (2000 km2) in the northwest of Washington, USA, is a valuable freshwater resource for regional municipalities, industry, and agriculture, and provides critical habitat for endangered salmon species. Due to a lack of spatially distributed long-term historical weather observations in the basin for downscaling purposes, we apply publically available statistically derived 1/16 degree gridded surface data along with the Distributed Hydrology Soil Vegetation Model (DHSVM; Wigmosta et al., 1992) with newly developed coupled dynamic glacier model (Clarke et al., 2015) to simulate hydrologic processes in the Nooksack River basin. We calibrate and validate the DHSVM to observed glacial mass balance and glacial ice extent as well as to observed daily streamflow and SNOTEL data in the Nooksack basin. For the historical period, we model using a gridded meteorological forcing data set (1950-2010; Livneh et al., 2013). We simulate forecasted climate change impacts, including glacial recession on streamflow, using gridded daily statically downscaled data from global climate models of the CMIP5 with RCP4.5 and RCP8.5 forcing scenarios developed using the multivariate adaptive constructed analogs method (Abatzoglou and Brown, 2011). Simulation results project an increase in winter streamflows due to more rainfall rather than snow, and a decrease in summer flows with a general shift in peak spring flows toward earlier in the spring. Glacier melt contribution to streamflow initially increases

  18. Some hydrological impacts of climate change for the Delaware River Basin

    Science.gov (United States)

    Tasker, Gary D.

    1990-01-01

    To gain insight into possible impacts of climate change on water availability in the Delaware River, two models are linked. The first model is a monthly water balance model that converts the temperature and precipitation values generated by a random number generator to monthly streamflow values. The monthly streamflow values are input to a second model that simulates the operation of reservoirs and diversions within the basin. The output for the two linked models consists of time series of reservoir levels and streamflow at key points in the basin. Model results for a base case, in which monthly temperature and precipitation statistics are unchanged from historical records, are compared to several changed-climate scenarios under a standard set of rules of operation.

  19. Managing the impact of climate change on the hydrology of the Gallocanta Basin, NE-Spain

    Science.gov (United States)

    Kuhn, N. J.

    2010-12-01

    The endorheic Gallocanta Basin represents an environment highly sensitive to climate change. Over the past 60 years, the Laguna de Gallocanta, an ephemeral lake situated in the centre of the Gallocanta basin, experienced a sequence of wet and dry phases. The lake and its surrounding wetlands are one of only a few bird sanctuaries left in NE-Spain for grey cranes on their annual migration from Scandinavia to northern Africa. Understanding the impact of climate change on basin hydrology is therefore of utmost importance for the appropriate management of the bird sanctuary. Changes in lake level are only weakly linked to annual rainfall, but strongly to individual events, with reaction times from hours to months after rainfall. Individual extreme event intensities as well as magnitudes affect lake level through both groundwater and surface runoff. In this study, the characteristics and frequencies of daily, event, monthly and bi-monthly rainfall over the past 60 years were analysed to assess the role of past, current and future rainfall characteristics for the lake level and its fluctuations. The results revealed a clear link between increased frequencies of high magnitude rainfall and phases of water filling in the Laguna de Gallocanta. In the middle of the 20th century, the rainfall recharge of groundwater appears to have been more important for lake level, while more recently the frequency of high magnitude rainfall and surface runoff has emerged as the dominant variable. In the Gallocanta Basin, climate change and the distinct and continuing land use change since Spain joined the EU in 1986 have created an environment that is in a more or less constant state of transition. This highlights two challenges faced by researchers involved in developing water management tools for the Gallocanta Basin in particular, but also other endorheic basins with sensitive and rapidly changing environments. Hydrologists have to understand the processes and the spatial and temporal

  20. Potential Impacts of Climate Change on Water Resources in the Kunhar River Basin, Pakistan

    Directory of Open Access Journals (Sweden)

    Rashid Mahmood

    2016-01-01

    Full Text Available Pakistan is one of the most highly water-stressed countries in the world and its water resources are greatly vulnerable to changing climatic conditions. The present study investigates the possible impacts of climate change on the water resources of the Kunhar River basin, Pakistan, under A2 and B2 scenarios of HadCM3, a global climate model. After successful development of the hydrological modeling system (HEC-HMS for the basin, streamflow was simulated for three future periods (2011–2040, 2041–2070, and 2071–2099 and compared with the baseline period (1961–1990 to explore the changes in different flow indicators such as mean flow, low flow, median flow, high flow, flow duration curves, temporal shift in peaks, and temporal shifts in center-of-volume dates. From the results obtained, an overall increase in mean annual flow was projected in the basin under both A2 and B2 scenarios. However, while summer and autumn showed a noticeable increase in streamflow, spring and winter showed decreased streamflow. High and median flows were predicted to increase, but low flow was projected to decrease in the future under both scenarios. Flow duration curves showed that the probability of occurrence of flow is likely to be more in the future. It was also noted that peaks were predicted to shift from June to July in the future, and the center-of-volume date—the date at which half of the annual flow passes—will be delayed by about 9–17 days in the basin, under both A2 and B2 scenarios. On the whole, the Kunhar basin will face more floods and droughts in the future due to the projected increase in high flow and decrease in low flow and greater temporal and magnitudinal variations in peak flows. These results highlight how important it is to take cognizance of the impact of climate change on water resources in the basin and to formulate suitable policies for the proper utilization and management of these resources.

  1. How are the wetlands over tropical basins impacted by the extreme hydrological events?

    Science.gov (United States)

    Al-Bitar, A.; Parrens, M.; Frappart, F.; Papa, F.; Kerr, Y. H.; Cretaux, J. F.; Wigneron, J. P.

    2016-12-01

    Wetlands play a crucial role in tropical basins and still many questions remain unanswered on how extreme events (like El-Nino) impacts them. Answering these questions is challenging as monitoring of inland water surfaces via remote sensing over tropical areas is a difficult task because of impact of vegetation and cloud cover. Several microwave based products have been elaborated to monitor these surfaces (Papa et al. 2010). In this study we combine the use of L-band microwave brightness temperatures and altimetric data from SARAL/ALTIKA to derive water storage maps at relatively high (7days) temporal frequency. The area of interest concerns the Amazon, Congo and GBH basins A first order radiative model is used to derive surface water over land from the brightness temperature measured by ESA SMOS mission at coarse resolution (25 km x 25 km) and 7-days frequency. An initial investigation of the use of the SMAP mission for the same purpose will be also presented. The product is compared to the static land cover map such as ESA CCI and the International Geosphere-Biosphere Program (IGBP) and also dynamic maps from SWAPS. It is then combined to the altimetric data to derive water storage maps. The water surfaces and water storage products are then compared to precipitation data from GPM TRMM datasets, ground water storage change from GRACE and river discharge data from field data. The amplitudes and time shifts of the signals is compared based on the sub-basin definition from Hydroshed database. The dataset is then divided into years of strong and weak El-Nino signal and the anomaly is between the two dataset is compared. The results show a strong influence of EL-Nino on the time shift of the different components showing that the hydrological regime of wetlands is highly impacted by these extreme events. This can have dramatic impacts on the ecosystem as the wetlands are vulnerable with a high biodiversity.

  2. Impact of land cover change on the environmental hydrology characteristics in Kelantan river basin, Malaysia

    Science.gov (United States)

    Saadatkhah, Nader; Mansor, Shattri; Khuzaimah, Zailani; Asmat, Arnis; Adnan, Noraizam; Adam, Siti Noradzah

    2016-09-01

    Changing the land cover/ land use has serious environmental impacts affecting the ecosystem in Malaysia. The impact of land cover changes on the environmental functions such as surface water, loss water, and soil moisture is considered in this paper on the Kelantan river basin. The study area at the east coast of the peninsular Malaysia has suffered significant land cover changes in the recent years. The current research tried to assess the impact of land cover changes in the study area focused on the surface water, loss water, and soil moisture from different land use classes and the potential impact of land cover changes on the ecosystem of Kelantan river basin. To simulate the impact of land cover changes on the environmental hydrology characteristics, a deterministic regional modeling were employed in this study based on five approaches, i.e. (1) Land cover classification based on Landsat images; (2) assessment of land cover changes during last three decades; (3) Calculation the rate of water Loss/ Infiltration; (4) Assessment of hydrological and mechanical effects of the land cover changes on the surface water; and (5) evaluation the impact of land cover changes on the ecosystem of the study area. Assessment of land cover impact on the environmental hydrology was computed with the improved transient rainfall infiltration and grid based regional model (Improved-TRIGRS) based on the transient infiltration, and subsequently changes in the surface water, due to precipitation events. The results showed the direct increased in surface water from development area, agricultural area, and grassland regions compared with surface water from other land covered areas in the study area. The urban areas or lower planting density areas tend to increase for surface water during the monsoon seasons, whereas the inter flow from forested and secondary jungle areas contributes to the normal surface water.

  3. Decoupling environmental impacts from industrial growth: Case study for South Morava river basin

    Directory of Open Access Journals (Sweden)

    Veljković Nebojša D.

    2015-01-01

    Full Text Available The widely accepted term ‘sustainable development’ is a comprehensive concept that requires multi-dimensional indicators showing links between economy, ecology and society. The concept of human development is obviously more complex than it could be understood from any aggregate economic index or from detailed sets of socio-economic statistical and ecological indicators. The research and analysis of the values of separation indicators for the Južna Morava basin agglomerations clearly show the impacts of industrial growth on the quality of the basin water bodies over the last three decades. Separation indicators have been derived from the statistical relationship between the situation indicators and drive indicators. The situation indicator SSWQIrb was derived as a composite index from ten chosen parameters which represent, by their quality, the characteristics of surface water, by reducing it to one index number weighed from the interrelation between the discharge at a given measurement station and the discharge at the exit profile of the basin. The index of the physical volume of industrial production (indexIND has been accepted as the drive indicator. The indicators were calculated as a series of index numbers with 1981 as the base year. The values of separation indicators, i.e. degree of separation and factor of separation show the least separation in the first decade (1981-1990 when the volume of industrial production (indexIND increased the most and the quality of the basin water bodies was the poorest (SSWQIrb. The improvement of the quality of basin water bodies in the last decade (2001-2010, marked by a higher value of the separation factor is a result of a slow growth of industrial production and positive impacts of an abrupt fall of total economic activity occurring already in the second decade (1991-2000. The research has confirmed the importance of applying the concepts of separation of economic growth from environmental impacts

  4. Basin-Scale Hydrologic Impacts of CO2 Storage: Regulatory and Capacity Implications

    Energy Technology Data Exchange (ETDEWEB)

    Birkholzer, J.T.; Zhou, Q.

    2009-04-02

    Industrial-scale injection of CO{sub 2} into saline sedimentary basins will cause large-scale fluid pressurization and migration of native brines, which may affect valuable groundwater resources overlying the deep sequestration reservoirs. In this paper, we discuss how such basin-scale hydrologic impacts can (1) affect regulation of CO{sub 2} storage projects and (2) may reduce current storage capacity estimates. Our assessment arises from a hypothetical future carbon sequestration scenario in the Illinois Basin, which involves twenty individual CO{sub 2} storage projects in a core injection area suitable for long-term storage. Each project is assumed to inject five million tonnes of CO{sub 2} per year for 50 years. A regional-scale three-dimensional simulation model was developed for the Illinois Basin that captures both the local-scale CO{sub 2}-brine flow processes and the large-scale groundwater flow patterns in response to CO{sub 2} storage. The far-field pressure buildup predicted for this selected sequestration scenario suggests that (1) the area that needs to be characterized in a permitting process may comprise a very large region within the basin if reservoir pressurization is considered, and (2) permits cannot be granted on a single-site basis alone because the near- and far-field hydrologic response may be affected by interference between individual sites. Our results also support recent studies in that environmental concerns related to near-field and far-field pressure buildup may be a limiting factor on CO{sub 2} storage capacity. In other words, estimates of storage capacity, if solely based on the effective pore volume available for safe trapping of CO{sub 2}, may have to be revised based on assessments of pressure perturbations and their potential impact on caprock integrity and groundwater resources, respectively. We finally discuss some of the challenges in making reliable predictions of large-scale hydrologic impacts related to CO{sub 2

  5. Snow Cover and Precipitation Impacts on Dry Season Streamflow in the Lower Mekong Basin

    Science.gov (United States)

    Cook, Benjamin I.; Bell, A. R.; Anchukaitis, K. J.; Buckley, B. M.

    2012-01-01

    Climate change impacts on dry season streamflow in the Mekong River are relatively understudied, despite the fact that water availability during this time is critically important for agricultural and ecological systems. Analyses of two gauging stations (Vientiane and Kratie) in the Lower Mekong Basin (LMB) show significant positive correlations between dry season (March through May, MAM) discharge and upper basin snow cover and local precipitation. Using snow cover, precipitation, and upstream discharge as predictors, we develop skillful regression models for MAM streamflow at Vientiane and Kratie, and force these models with output from a suite of general circulation model (GCM) experiments for the twentieth and twenty-first centuries. The GCM simulations predict divergent trends in snow cover (decreasing) and precipitation (increasing) over the twenty-first century, driving overall negligible long-term trends in dry season streamflow. Our study demonstrates how future changes in dry season streamflow in the LMB will depend on changes in snow cover and precipitation, factors that will need to be considered when assessing the full basin response to other climatic and non-climatic drivers.

  6. An Impact Model of the Imbrium Basin for Distribution of Thorium on Lunar Surface

    Institute of Scientific and Technical Information of China (English)

    ZHU Meng-Hua; LIU Liang-Gang; XU Ao-Ao

    2008-01-01

    @@ We consider the thorium distributions that are coincident with the distribution of ejecta after the Mare Imbrium impact occurs on the lunar surface and derive a simple model on the sphericaJ target to predict the thickness of Imbrium ejecta deposits as a function of distance from the centre of the Imbrium basin.Then we use the result of Lunar Prospector's gamma ray experiment to test the hypothesis that the distribution of thorium on the lunar surface has an origin from the Mare Imbrium.

  7. The Impact of Water Diversion on Groundwater Resources in an Inland River Basin

    Science.gov (United States)

    Huang, L.; Zheng, C.

    2012-12-01

    The Heihe River Basin (HRB) is one of the most intensely exploited and ecologically stressed inland river basins in the world. The HRB is characterized by three distinct ecohydrological systems: the mountainous upper reach where most of the water resources for the HRB originate from the rainfall, snow and permafrost; the middle reach with an arid climate and irrigated agriculture; and the lower reach dominated by wide stretches of Gobi desert. The study site, Zhangye Basin, is situated in the middle reach. It contains 92% population of the HRB and consumes about 80% of water resources as a regional agricultural and industrial center. To improve the deteriorating health of the ecosystems in the lower HRB, the Chinese government initiated the Heihe Water Diversion Project (HWDP) in 2000, which stipulated that at least 0.95 billion cubic meters of surface water must be delivered from the middle reach to the lower reach annually. A three-dimensional groundwater flow model has been developed for the Zhangye Basin to understand groundwater-surface water interactions in the Zhangye Basin and assess how the HWDP project has impacted the groundwater availability and water budgets in the region. The flow model has been reasonably calibrated using multiple sources of field data. The output of the groundwater model provided estimates of head differences before and after the HWDP project between 1999 and 2010. The results show that the groundwater level has declined widely, except in the Zhangye urban area where the groundwater level has increased by 0.5 to 7m and a few other localized spots. The calculated water budgets indicate that the spring discharge to the Heihe River has been continuously decreasing, and the total river leakage to the aquifer has been increasing. These results are in reasonable agreement with those from previous studies based on independent water balance calculation. The groundwater model is being integrated with surface water and land use data to

  8. Urbanization Impacts on Flooding in the Kansas River Basin and Evaluation of Wetlands as a Mitigation Measure

    Science.gov (United States)

    This study evaluates the impacts of future land use changes on flooding in the Kansas River Basin. It also studies the impacts of wetlands on flood reduction. The study presents Hydrologic Engineering Centers-Hydrologic Modeling System (HEC-HMS) based runoff modeling and River A...

  9. Managing the impact of climate change on the hydrology of the Gallocanta Basin, NE-Spain.

    Science.gov (United States)

    Kuhn, Nikolaus J; Baumhauer, Roland; Schütt, Brigitta

    2011-02-01

    The Gallocanta Basin represents an environment highly sensitive to climate change. Over the past 60 years, the Laguna de Gallocanta, an ephemeral lake situated in the closed Gallocanta basin, experienced a sequence of wet and dry phases. The lake and its surrounding wetlands are one of only a few bird sanctuaries left in NE-Spain for grey cranes on their annual migration from Scandinavia to northern Africa. Understanding the impact of climate change on basin hydrology is therefore of utmost importance for the appropriate management of the bird sanctuary. Changes in lake level are only weakly linked to annual rainfall, with reaction times between hours and months after rainfall. Both the total amount of rainfall over the reaction period, as well as individual extreme events, affect lake level. In this study the characteristics and frequencies of daily, event, monthly and bi-monthly rainfall over the past 60 years were analysed. The results revealed a clear link between increased frequencies of high magnitude rainfall and phases of water filling in the Laguna de Gallocanta. In the middle of the 20th century, the absolute amount of rainfall appears to have been more important for lake level, while more recently the frequency of high magnitude rainfall has emerged as the dominant variable. In the Gallocanta Basin, climate change and the distinct and continuing land use change since Spain joined the EU in 1986 have created an environment that is in a more or less constant state of transition. This highlights two challenges faced by hydrologists and climatologists involved in developing water management tools for the Gallocanta Basin in particular, but also other areas with sensitive and rapidly changing environments. Hydrologists have to understand the processes and the spatial and temporal patterns of surface-climate interaction in a watershed to assess the impact of climate change on its hydrology. Climatologists, on the other hand, have to develop climate models

  10. Impacts of Climate Change on Stream Flow in the Upper Mississippi River Basin: A Regional Climate Model Perspective, The

    OpenAIRE

    Manoj Jha; Zaitao Pan; Takle, Eugene S.; Roy Gu

    2003-01-01

    We evaluate the impact of climate change on stream flow in the Upper Mississippi River Basin (UMRB) by using a regional climate model (RCM) coupled with a hydrologic model, the Soil and Water Assessment Tool (SWAT). The SWAT model was calibrated and validated against measured stream flow data using observed weather data and inputs from the Environmental Protection Agency's BASINS (Better Assessment Science Integrating Point and Nonpoint Sources) geographical information/database system. The c...

  11. Climate change impacts on snow water availability in the Euphrates-Tigris basin

    Directory of Open Access Journals (Sweden)

    M. Özdoğan

    2011-04-01

    to be indicative of climate change impacts on the water resources of the Euphrates-Tigris basin.

  12. Assessment of climate change impacts on meteorological and hydrological droughts in the Jucar River Basin

    Science.gov (United States)

    Marcos-Garcia, Patricia; Pulido-Velazquez, Manuel; Lopez-Nicolas, Antonio

    2016-04-01

    Extreme natural phenomena, and more specifically droughts, constitute a serious environmental, economic and social issue in Southern Mediterranean countries, common in the Mediterranean Spanish basins due to the high temporal and spatial rainfall variability. Drought events are characterized by their complexity, being often difficult to identify and quantify both in time and space, and an universally accepted definition does not even exist. This fact, along with future uncertainty about the duration and intensity of the phenomena on account of climate change, makes necessary increasing the knowledge about the impacts of climate change on droughts in order to design management plans and mitigation strategies. The present abstract aims to evaluate the impact of climate change on both meteorological and hydrological droughts, through the use of a generalization of the Standardized Precipitation Index (SPI). We use the Standardized Flow Index (SFI) to assess the hydrological drought, using flow time series instead of rainfall time series. In the case of the meteorological droughts, the Standardized Precipitation and Evapotranspiration Index (SPEI) has been applied to assess the variability of temperature impacts. In order to characterize climate change impacts on droughts, we have used projections from the CORDEX project (Coordinated Regional Climate Downscaling Experiment). Future rainfall and temperature time series for short (2011-2040) and medium terms (2041-2070) were obtained, applying a quantile mapping method to correct the bias of these time series. Regarding the hydrological drought, the Témez hydrological model has been applied to simulate the impacts of future temperature and rainfall time series on runoff and river discharges. It is a conceptual, lumped and a few parameters hydrological model. Nevertheless, it is necessary to point out the time difference between the meteorological and the hydrological droughts. The case study is the Jucar river basin

  13. Assessment of potential impacts of climate change on agricultural development in the Lower Benue River Basin.

    Science.gov (United States)

    Abah, Roland Clement; Petja, Brilliant Mareme

    2016-12-01

    Agriculture in the Lower Benue River Basin faces several challenges which threaten the future of agricultural development. This study was an assessment of potential impacts of climate change on agricultural development in the Lower Benue River Basin. Through analysis of physical and socioeconomic parameters, the study adapted an impact assessment model to rank potential impacts on agricultural development in the study area. Rainfall intensity seemed to be increasing with a gradual reduction in the number of rainy days. The average discharge at Makurdi hydrological station was 3468.24 cubic metres per second (m(3) s(-1)), and the highest peak flow discharge was 16,400 m(3) s(-1). The daily maximum temperature and annual temperature averages for the study area are gradually rising leading to increased heat stress. Physical and chemical analyses showed that the soils are moderately fertile but require effective application of inorganic and organic fertilisers. The main occupational activities in the study area are agricultural based. The identified potential impacts of climate change on agriculture were categorised under atmospheric carbon dioxides and oxides, rainfall intensity, frequency of floods and droughts, temperature intensity and variation, heat stress, surface water trends, and soil quality and fertility. The identified potential impacts related to population dynamics on agriculture were categorised under population growth, rural-urban migration, household income and infectious diseases and HIV and AIDS. Community-level mitigation strategies were proffered. Policy makers are advised to promote irrigation farming, support farmers with farm inputs and credit facilities and establish active agricultural extension services to support the sustainable development of agriculture.

  14. Assessment of the hydrological impacts of green roof: From building scale to basin scale

    Science.gov (United States)

    Versini, P.-A.; Ramier, D.; Berthier, E.; de Gouvello, B.

    2015-05-01

    At the building scale, the use of green roof has shown a positive impact on urban runoff (decrease and slow-down in peak discharge, decrease in runoff volume). The present work aims to study whether similar effects are possible at the basin scale and what is the minimum spreading of green runoff needed to observe significant impacts. It is particularly focused on the circumstances of such impacts and how they can contribute to storm water management in urban environment. Based on observations on experimental green roofs, a conceptual model has been developed and integrated into the SWMM urban rainfall-runoff model to reproduce the hydrological behaviour of two different types of green roof. It has been combined with a method defining green roofing scenarios by estimating the maximum roof area that can be covered. This methodology has been applied on a long time series (18 years) to the Châtillon urban basin (Haut-de-Seine county, France) frequently affected by urban flooding. For comparison, the same methodology has been applied at the building scale and a complementary analysis has been conducted to study which hydrometeorological variables may affect the magnitude of these hydrological impacts at both scales. The results show green roofs, when they are widely implemented, can affect urban runoff in terms of peak discharge and volume, and avoid flooding in several cases. Both precipitation - generally accumulated during the whole event- and the initial substrate saturation are likely to have an impact on green roof effects. In this context, the studied green roofs seem useful to mitigate the effects of usual rainfall events but turn out being less helpful for the more severe ones. We conclude that, combined with other infrastructures, green roofs represent an interesting contribution to urban water management in the future.

  15. Impact of Inter‐Basin Water Transfer Projects on Regional Ecological Security from a Telecoupling Perspective

    Directory of Open Access Journals (Sweden)

    Yuan Quan

    2016-02-01

    Full Text Available Inter‐basin water transfer projects (IBWTPs offer one of the most important means to solve the mismatch between supply and demand of regional water resources. IBWTPs have impacts on the complex ecosystems of the areas from which water is diverted and to which water is received. These impacts increase damage or risk to regional ecological security and human wellbeing. However, current methods make it difficult to achieve comprehensive analysis of the impacts of whole ecosystems, because of the long distance between ecosystems and the inconsistency of impact events. In this study, a model was proposed for the analysis of the impacts of IBWTPs on regional ecological security. It is based on the telecoupling framework, and the Driver‐Pressure‐State‐ Impact‐Response (DPSIR model was used to improve the analysis procedure within the telecoupling framework. The Middle Line of the South‐to‐North Water Diversion Project was selected as a case study to illustrate the specific analysis procedure. We realized that information sharing is a key issue in the management of regional security, and that the ecological water requirement, in the form of a single index, could be used to quantitatively assess the impacts on ecological security from IBWTPs.

  16. Re-plumbing the Terrestrial Hydrosphere: Scope and Impact of Major Inter-basin Water Transfers

    Science.gov (United States)

    Shikhmacheva, K. V.; Vorosmarty, C. J.; Fekete, B. M.; Afshari, S.; Aside, B.; Chibisova, Y.; Dopson, I.; Link, H.; Mouden, A.

    2013-12-01

    The availability of water has become one of the main concerns in modern history and it is an important policymaking strategy. Increasing population, agricultural intensification, rapid urbanization, industrial expansion and environmental changes increase water demand on region and global scales. Inter-Basin Water Transfer (IBWT) is an important element of satisfying immediate water requirements. The complex engineering structures divert water flow between watersheds, thus ';re-plumbing' terrestrial hydrosphere. We report here an analysis of inter-basin water transfer for the Northeast region, which is a part of an NSF funded project entitled 'The NorthEast Regional Earth System Model (NE-RESM).' In addition, this work is also a part of a global IBWT study. First, we present the IBWT geo-referenced assembled data set, derived from from maps, published documents and online resources. The information in the data base was classified by project name, diverted volume, source location, usage, status of construction, transport distance and purpose. The key feature of the dataset is geo-location of the projects, that allows further analysis of the hydrologic impact of each of the projects as well as their collective significance. Upon completion of the data-collection phase, the inputs were verified using RiverGIS and ArcGIS software. In addition, we investigated some key measures of IBWT distortion of regional-scale hydrology as well as their socio-economic impacts across the Northeast region. We calculated several indicators to assess these impacts, for example the donor-to-recipient basin flow ratio, which represents the 'gain' and 'loss' of water relative to the natural flow on a basin scale. Elements of the regional IBWT data base will be incorporated into the regional-scale Water Balance Model (WBM), and linked to the operation of reservoirs and dams. While focused on the Northeastern U.S., we believe that this data, its testing and applications will yield broad use

  17. Assessing the impact of climate change on potential evapotranspiration in Aksu River Basin

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shouhong; LIU Suxia; MO Xingguo; SHU Chang; SUN Yang; ZHANG Chun

    2011-01-01

    Evapotranspiration is one of the key components of hydrological processes.Assessing the impact of climate factors on evapotranspiration is helpful in understanding the impact of climate change on hydrological processes.In this paper,based on the daily meteorological data from 1960 to 2007 within and around the Aksu River Basin,reference evapotranspiration (RET) was estimated with the FAO Penman-Monteith method.The temporal and spatial variations of RET were analyzed by using ARCGIS and Mann-Kendall method.Multiple Regression Analysis was employed to attribute the effects of the variations of air temperature,solar radiation,relative humidity,vapour pressure and wind speed on RET.The results showed that average annual RET in the eastern plain area of the Aksu River Basin was about 1100 mm,which was nearly twice as much as that in the western mountainous area.The trend of annual RET had significant spatial variability.Annual RET was reduced significantly in the southeastern oasis area and southwestern plain area and increased slightly in the mountain areas.The amplitude of the change of RET reached the highest in summer,contributing most of the annual change of RET.Except in some high elevation areas where relative humidity predominated the change of the RET,the variations of wind velocity predominated the changes of RET almost throughout the basin.Taking Kuqa and Ulugqat stations as an example,the variations of wind velocity accounted for more than 50% of the changes of RET.

  18. Multi-model climate impact assessment and intercomparison for three large-scale river basins on three continents

    Science.gov (United States)

    Vetter, T.; Huang, S.; Aich, V.; Yang, T.; Wang, X.; Krysanova, V.; Hattermann, F.

    2014-07-01

    Climate change impacts on hydrological processes should be simulated for river basins using validated models and multiple climate scenarios in order to provide reliable results for stakeholders. In the last 10-15 years climate impact assessment was performed for many river basins worldwide using different climate scenarios and models. Nevertheless, the results are hardly comparable and do not allow to create a full picture of impacts and uncertainties. Therefore, a systematic intercomparison of impacts is suggested, which should be done for representative regions using state-of-the-art models. Our study is intended as a step in this direction. The impact assessment presented here was performed for three river basins on three continents: Rhine in Europe, Upper Niger in Africa and Upper Yellow in Asia. For that, climate scenarios from five GCMs and three hydrological models: HBV, SWIM and VIC, were used. Four "Representative Concentration Pathways" (RCPs) covering a range of emissions and land-use change projections were included. The objectives were to analyze and compare climate impacts on future trends considering three runoff quantiles: Q90, Q50 and Q10 and on seasonal water discharge, and to evaluate uncertainties from different sources. The results allow drawing some robust conclusions, but uncertainties are large and shared differently between sources in the studied basins. The robust results in terms of trend direction and slope and changes in seasonal dynamics could be found for the Rhine basin regardless which hydrological model or forcing GCM is used. For the Niger River scenarios from climate models are the largest uncertainty source, providing large discrepancies in precipitation, and therefore clear projections are difficult to do. For the Upper Yellow basin, both the hydrological models and climate models contribute to uncertainty in the impacts, though an increase in high flows in future is a robust outcome assured by all three hydrological models.

  19. Multi-model climate impact assessment and intercomparison for three large-scale river basins on three continents

    Directory of Open Access Journals (Sweden)

    T. Vetter

    2014-07-01

    Full Text Available Climate change impacts on hydrological processes should be simulated for river basins using validated models and multiple climate scenarios in order to provide reliable results for stakeholders. In the last 10–15 years climate impact assessment was performed for many river basins worldwide using different climate scenarios and models. Nevertheless, the results are hardly comparable and do not allow to create a full picture of impacts and uncertainties. Therefore, a systematic intercomparison of impacts is suggested, which should be done for representative regions using state-of-the-art models. Our study is intended as a step in this direction. The impact assessment presented here was performed for three river basins on three continents: Rhine in Europe, Upper Niger in Africa and Upper Yellow in Asia. For that, climate scenarios from five GCMs and three hydrological models: HBV, SWIM and VIC, were used. Four "Representative Concentration Pathways" (RCPs covering a range of emissions and land-use change projections were included. The objectives were to analyze and compare climate impacts on future trends considering three runoff quantiles: Q90, Q50 and Q10 and on seasonal water discharge, and to evaluate uncertainties from different sources. The results allow drawing some robust conclusions, but uncertainties are large and shared differently between sources in the studied basins. The robust results in terms of trend direction and slope and changes in seasonal dynamics could be found for the Rhine basin regardless which hydrological model or forcing GCM is used. For the Niger River scenarios from climate models are the largest uncertainty source, providing large discrepancies in precipitation, and therefore clear projections are difficult to do. For the Upper Yellow basin, both the hydrological models and climate models contribute to uncertainty in the impacts, though an increase in high flows in future is a robust outcome assured by all three

  20. Domestication and early agriculture in the Mediterranean Basin: Origins, diffusion, and impact.

    Science.gov (United States)

    Zeder, Melinda A

    2008-08-19

    The past decade has witnessed a quantum leap in our understanding of the origins, diffusion, and impact of early agriculture in the Mediterranean Basin. In large measure these advances are attributable to new methods for documenting domestication in plants and animals. The initial steps toward plant and animal domestication in the Eastern Mediterranean can now be pushed back to the 12th millennium cal B.P. Evidence for herd management and crop cultivation appears at least 1,000 years earlier than the morphological changes traditionally used to document domestication. Different species seem to have been domesticated in different parts of the Fertile Crescent, with genetic analyses detecting multiple domestic lineages for each species. Recent evidence suggests that the expansion of domesticates and agricultural economies across the Mediterranean was accomplished by several waves of seafaring colonists who established coastal farming enclaves around the Mediterranean Basin. This process also involved the adoption of domesticates and domestic technologies by indigenous populations and the local domestication of some endemic species. Human environmental impacts are seen in the complete replacement of endemic island faunas by imported mainland fauna and in today's anthropogenic, but threatened, Mediterranean landscapes where sustainable agricultural practices have helped maintain high biodiversity since the Neolithic.

  1. Climate change impacts on snow water availability in the Euphrates-Tigris basin

    Directory of Open Access Journals (Sweden)

    M. Özdoğan

    2011-09-01

    Full Text Available This study investigates the effects of projected climate change on snow water availability in the Euphrates-Tigris basin using the Variable Infiltration Capacity (VIC macro scale hydrologic model and a set of regional climate-change outputs from 13 global circulation models (GCMs forced with two greenhouse gas emission scenarios for two time periods in the 21st century (2050 and 2090. The hydrologic model produces a reasonable simulation of seasonal and spatial variation in snow cover and associated snow water equivalent (SWE in the mountainous areas of the basin, although its performance is poorer at marginal snow cover sites. While there is great variation across GCM outputs influencing snow water availability, the majority of models and scenarios suggest a significant decline (between 10 and 60 percent in available snow water, particularly under the high-impact A2 climate change scenario and later in the 21st century. The changes in SWE are more stable when multi-model ensemble GCM outputs are used to minimize inter-model variability, suggesting a consistent and significant decrease in snow-covered areas and associated water availability in the headwaters of the Euphrates-Tigris basin. Detailed analysis of future climatic conditions point to the combined effects of reduced precipitation and increased temperatures as primary drivers of reduced snowpack. Results also indicate a more rapid decline in snow cover in the lower elevation zones than the higher areas in a changing climate but these findings also contain a larger uncertainty. The simulated changes in snow water availability have important implications for the future of water resources and associated hydropower generation and land-use management and planning in a region already ripe for interstate water conflict. While the changes in the frequency and intensity of snow-bearing circulation systems or the interannual variability related to climate were not considered, the simulated

  2. Impact of multi-purpose aquifer utilisation on a variable-density groundwater flow system in the Gippsland Basin, Australia

    Science.gov (United States)

    Varma, Sunil; Michael, Karsten

    2012-02-01

    The Latrobe aquifer in the Gippsland Basin in southeastern Australia is a prime example for emerging resource conflicts in Australian sedimentary basins. The Latrobe Group forms a major freshwater aquifer in the onshore Gippsland Basin, and is an important reservoir for oil and gas in both onshore and offshore parts of the basin. The Latrobe Group and overlying formations contain substantial coal resources that are being mined in the onshore part of the basin. These may have coal-seam-gas potential and, in addition, the basin is considered prospective for its geothermal energy and CO2 storage potential. The impacts of groundwater extraction related to coal-mine dewatering, public water supply, and petroleum production on the flow of variable-density formation water has been assessed using freshwater hydraulic heads and impelling force vectors. Groundwater flows from the northern and western edges towards the central part of the basin. Groundwater discharge occurs mainly offshore along the southern margin. Post-stress hydraulic heads show significant declines near the petroleum fields and in the coal mining areas. A hydrodynamic model of the Latrobe aquifer was used to simulate groundwater recovery in the Latrobe aquifer from different scenarios of cessation of groundwater and other fluid extractions.

  3. Bouguer gravity anomaly of the Moon from CE-1 topography data:Implications for the impact basin evolution

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this study,the terrain correction for lunar free-air gravity anomaly (FAGA) is calculated in spherical coordinates based on the global topography data detected by the laser altimeter on Chang’E-1 (CE-1). The obtained lunar Bouguer gravity anomaly (BGA) reveals density irregularities of the interior mass. BGA is important in characterizing the mascon basins. According to the BGA of the Moon,the South Pole-Aitken (SPA) basin is considered the largest mascon basin on the Moon,and the feature of BGA in the basin implies the impacting direction. Further,the mascon basins seem to be classified into two types,Type Highland and Type Plain. For the mascon basins of Type Highland the dense materials mainly come from the shallow crust,which are associated with the basalt deposits. The other type,Type Plain,includes mascon basins whose major dense materials may be located deep at the litho-sphere,corresponding to the uplifted mantle.

  4. Modeling Impact of Climate Change on Water Resources and Agriculture Demand in the Volta Basin and other Basin Systems in Ghana

    Directory of Open Access Journals (Sweden)

    Barnabas A. Amisigo

    2015-05-01

    Full Text Available An assessment of the impacts of projected climate change on water availability and crop production in the Volta Basin and the southwestern and coastal basin systems of Ghana has been undertaken as a component of the impacts and adaptation study for Ghana by UNU-WIDER and the University of Ghana. Four climate change scenarios were considered in addition to a reference (no change scenario—two dry and two wet scenarios. To conduct the analysis, a portion of a special framework using three water models was used; the framework is called the Strategic Analysis of Climate resilient Development (SACReD. First, the CliRun water balance model was used to simulate catchment runoffs using projected rainfall and temperature under the scenarios. Second, climate impacts on yields of the economically important Ghana crops were modeled using the AquaCrop software. Third, the Water Evaluation and Planning (WEAP software was used for the water allocation modeling. The results show that all water demands (municipal, hydropower, and agriculture cannot be simultaneously met currently, or under any of the scenarios used, including the wet scenarios. This calls for an evaluation of groundwater as an additional source of water supply and an integrated water resources management plan in the catchments to balance demand with supply and ensure sustainable socio-economic development. In addition, the AquaCrop model forecasts negative impacts for the crop yields studied, with some crops and regions seeing larger impacts than others.

  5. Detection of meteo-hydrological trends and water resources impacts at the basin scale

    Science.gov (United States)

    Anghileri, Daniela; Pianosi, Francesca; Soncini-Sessa, Rodolfo

    2013-04-01

    Trend detection is a classical topic of time series analysis and has gained renewed interest in the last years in climate change research. When dealing with hydrological time series, trend detection is made more complex by the seasonality and the interannual variability that characterize natural catchments. Furthermore, the impacts of detected hydrological trends on water resources at the catchment scale is a relatively less explored issue, although of high relevance for stakeholders and decision-makers. In this study we address such topics investigating the relation between hydro-climatic trends and their impacts on water resources at the basin scale by application to the regulated Alpine lake Maggiore, at the border between Switzerland and Italy. This case study is particularly interesting because of the relevance of the socio-economic component in the system, especially the issues of flood control and downstream irrigation supply, and the high seasonality and interannual variability of the climatic and hydrological system. We propose several graphical tools to effectively visualize the results of traditional trend detection methods like the Mann-Kendall test and the Sen method, and a novel tool, named Moving Average over Shifting Horizon (MASH), which allows to simultaneously tackle seasonality and interannual variability. We also show and discuss how these tools can be applied to quantify the impacts of the detected meteo-hydrological changes on water resources at the basin scale. In our case study, numerical results demonstrate that significant hydrological trends have occurred in the last 25 years, and that they can be reasonably ascribed to changes in the meteorological regime. The consequences of hydrological changes on water resources, namely flood protection along the lake shores and downstream irrigation supply, are less clear, possibly because of non-linearity and threshold effects.

  6. Assessing climate change impacts on fresh water resources of the Athabasca River Basin, Canada.

    Science.gov (United States)

    Shrestha, Narayan Kumar; Du, Xinzhong; Wang, Junye

    2017-12-01

    Proper management of blue and green water resources is important for the sustainability of ecosystems and for the socio-economic development of river basins such as the Athabasca River Basin (ARB) in Canada. For this reason, quantifying climate change impacts on these water resources at a finer temporal and spatial scale is often necessary. In this study, we used a Soil and Water Assessment Tool (SWAT) to assess climate change impacts on fresh water resources, focusing explicitly on the impacts to both blue and green water. We used future climate data generated by the Canadian Center for Climate Modelling and Analysis Regional Climate Model (CanRCM4) with a spatial resolution of 0.22°×0.22° (~25km) for two emission scenarios (RCP 4.5 and 8.5). Results projected the climate of the ARB to be wetter by 21-34% and warmer by 2-5.4°C on an annual time scale. Consequently, the annual average blue and green water flow was projected to increase by 16-54% and 11-34%, respectively, depending on the region, future period, and emission scenario. Furthermore, the annual average green water storage at the boreal region was expected to increase by 30%, while the storage was projected to remain fairly stable or decrease in other regions, especially during the summer season. On average, the fresh water resources in the ARB are likely to increase in the future. However, evidence of temporal and spatial heterogeneity could pose many future challenges to water resource planners and managers. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  7. Supplemental irrigation potential and impact on downstream flow of Karkheh River basin in Iran

    Science.gov (United States)

    Hessari, Behzad; Bruggeman, Adriana; Akhoond-Ali, Ali Mohammad; Oweis, Theib; Abbasi, Fariborz

    2016-05-01

    Supplemental irrigation of rainfed winter crops improves and stabilises crop yield and water productivity. Although yield increases by supplemental irrigation are well established at the field level, its potential extent and impact on water resources at the basin level are less researched. This work presents a Geographic Information Systems (GIS)-based methodology for identifying areas that are potentially suitable for supplemental irrigation and a computer routine for allocating streamflow for supplemental irrigation in different sub-basins. A case study is presented for the 42 908 km2 upper Karkheh River basin (KRB) in Iran, which has 15 840 km2 of rainfed crop areas. Rainfed crop areas within 1 km from the streams, with slope classes 0-5, 0-8, 0-12, and 0-20 %, were assumed to be suitable for supplemental irrigation. Four streamflow conditions (normal, normal with environmental flow requirements, drought and drought with environmental flow) were considered for the allocation of water resources. Thirty-seven percent (5801 km2) of the rainfed croplands had slopes less than 5 %; 61 % (3559 km2) of this land was suitable for supplemental irrigation, but only 22 % (1278 km2) could be served with irrigation in both autumn (75 mm) and spring (100 mm), under normal flow conditions. If irrigation would be allocated to all suitable land with slopes up to 20 %, 2057 km2 could be irrigated. This would reduce the average annual outflow of the upper KRB by 9 %. If environmental flow requirements are considered, a maximum (0-20 % slopes) of 1444 km2 could receive supplemental irrigation. Under drought conditions a maximum of 1013 km2 could be irrigated, while the outflow would again be reduced by 9 %. Thus, the withdrawal of streamflow for supplemental irrigation has relatively little effect on the outflow of the upper KRB. However, if the main policy goal would be to improve rainfed areas throughout the upper KRB, options for storing surface water need to be developed.

  8. Uncertainty in climate change impacts on water resources in the Rio Grande Basin, Brazil

    Directory of Open Access Journals (Sweden)

    M. T. Nóbrega

    2011-02-01

    Full Text Available We quantify uncertainty in the impacts of climate change on the discharge of Rio Grande, a major tributary of the Paraná River in South America and one of the most important basins in Brazil for water supply and hydro-electric power generation. We consider uncertainty in climate projections associated with the greenhouse-gas emission scenarios (A1b, A2, B1, B2 and increases in global mean air temperature of 1 to 6° C for the HadCM3 GCM (Global Circulation Model as well as uncertainties related to GCM structure. For the latter, multimodel runs using 6 GCMs (CCCMA CGCM31, CSIRO Mk30, IPSL CM4, MPI ECHAM5, NCAR CCSM30, UKMO HadGEM1 and HadCM3 as baseline, for a +2° C increase in global mean temperature. Pattern-scaled GCM-outputs are applied to a large-scale hydrological model (MGB-IPH of Rio Grande Basin. Based on simulations using HadCM3, mean annual river discharge increases, relative to the baseline or control run period (1961–1990, by +5% to +10% under the SRES emissions scenarios and from +8% to +51% with prescribed increases in global mean air temperature of between 1 and 6° C. Substantial uncertainty in projected changes to mean river discharge (−28% to +13% under the 2° C warming scenario is, however, associated with the choice of GCM. We conclude that, in the case of Rio Grande Basin, the most important source of uncertainty derives from the GCM rather than the emission scenario or the magnitude of rise in mean global temperature.

  9. Temporal clustering of floods and impacts of climate indices in the Tarim River basin, China

    Science.gov (United States)

    Gu, Xihui; Zhang, Qiang; Singh, Vijay P.; Chen, Yongqin David; Shi, Peijun

    2016-12-01

    The occurrence rates of floods in Tarim River basin, the largest arid basin in China, were estimated using the Peak-over-Threshold (POT) technique. The intra-annual, seasonal and inter-annual clustering of floods was then analyzed using the Cox regression model, month frequency method and dispersion index, respectively. Possible impacts of climate indices on the occurrence rates were also investigated. Both NAO and AO are selected as significant covariates to occurrence rates of floods in Tarim River basin by Cox regression model, suggesting occurrence of flood events is not independent, but exhibits temporal clustering in intra-annual scale. On the basis of the results of the station and region-wide modeling by Cox regression model, we suggest using a model in which the rate of occurrence depends on monthly averaged NAO or AO. The Cox regression model not only can be used to assess the time-varying rate of flood occurrence, but also has the capability to forecast the predictors. Flood occurrence time and probability of exceedance are changing with climate index from negative to positive on both station and region scale. In addition, seasonal clustering of station-based floods and regional observed floods are also identified with mainly concentrating from June to August. Meanwhile, dispersion index is used to evaluate the inter-annual clustering of annual number of flood occurrences both on station and region. We found that inter-annual clustering of regional floods is more evident than that of station-based floods, indicating that regional observed flood records are generally over-dispersed with a tendency for flood events to cluster in time.

  10. Climate Change Impact on Variability of Rainfall Intensity in Upper Blue Nile Basin, Ethiopia

    Science.gov (United States)

    Worku, L. Y.

    2015-12-01

    Extreme rainfall events are major problems in Ethiopia with the resulting floods that usually could cause significant damage to agriculture, ecology, infrastructure, disruption to human activities, loss of property, loss of lives and disease outbreak. The aim of this study was to explore the likely changes of precipitation extreme changes due to future climate change. The study specifically focuses to understand the future climate change impact on variability of rainfall intensity-duration-frequency in Upper Blue Nile basin. Precipitations data from two Global Climate Models (GCMs) have been used in the study are HadCM3 and CGCM3. Rainfall frequency analysis was carried out to estimate quantile with different return periods. Probability Weighted Method (PWM) selected estimation of parameter distribution and L-Moment Ratio Diagrams (LMRDs) used to find the best parent distribution for each station. Therefore, parent distributions for derived from frequency analysis are Generalized Logistic (GLOG), Generalized Extreme Value (GEV), and Gamma & Pearson III (P3) parent distribution. After analyzing estimated quantile simple disaggregation model was applied in order to find sub daily rainfall data. Finally the disaggregated rainfall is fitted to find IDF curve and the result shows in most parts of the basin rainfall intensity expected to increase in the future. As a result of the two GCM outputs, the study indicates there will be likely increase of precipitation extremes over the Blue Nile basin due to the changing climate. This study should be interpreted with caution as the GCM model outputs in this part of the world have huge uncertainty.

  11. Uncertainty in climate change impacts on water resources in the Rio Grande Basin, Brazil

    Directory of Open Access Journals (Sweden)

    M. T. Nóbrega

    2010-08-01

    Full Text Available We quantify uncertainty in the impacts of climate change on the discharge of the Rio Grande, a major tributary of the River Paraná in South America and one of the most important basins in Brazil for water supply and hydro-electric power generation. We consider uncertainty in climate projections associated with the SRES (greenhouse-gas emission scenarios (A1b, A2, B1, B2 and increases in global mean air temperature of 1 to 6 °C for the HadCM3 GCM as well as uncertainties related to GCM structure. For the latter, multimodel runs using 6 GCMs (CCCMA CGCM31, CSIRO Mk30, IPSL CM4, MPI ECHAM5, NCAR CCSM30, UKMO HadGEM1 and HadCM3 as baseline, for a + 2 °C increase in global mean temperature. Pattern-scaled GCM-outputs are applied to a large-scale hydrological model (MGB-IPH of the Rio Grande Basin. Based on simulations using HadCM3, mean annual river discharge increases, relative to the baseline period (1961–1990, by + 5% to + 10% under the SRES emissions scenarios and from + 8% to + 51% with prescribed increases in global mean air temperature of between 1 and 6 °C. Substantial uncertainty in projected changes to mean river discharge (− 28% to + 13% under the 2 °C warming scenario is, however, associated with the choice of GCM. We conclude that, in the case of the Rio Grande Basin, the most important source of uncertainty derives from the GCM rather than the emission scenario or the magnitude of rise in mean global temperature.

  12. Human impacts on the Changjiang (Yangtze) River basin, China, with special reference to the impacts on the dry season water discharges into the sea

    Science.gov (United States)

    Chen, Xiqing; Zong, Yongqiang; Zhang, Erfeng; Xu, Jiangang; Li, Shijie

    2001-11-01

    The annual mean discharge from the upper Changjiang (Yangtze) basin has shown a significant decreasing trend since the end of the 19th century. Since the 1970s, the monthly mean discharge to the sea has also shown a dramatic decrease during dry seasons. This paper examines the human impacts on the major hydrological processes in the Changjiang River basin, with a special focus on their influence on the discharge from the drainage basin to the sea during the dry season. Climatic warming has been obvious since the 1960s in the headwater area, resulting a continuous retreat of glaciers, while the increased evaporation is responsible for the dropping of lake water levels and decrease in water area. Such a trend continuing into the coming decades will significantly change the seasonal hydrological processes, especially the dry-season discharges from the upper basin. The decreasing vegetation cover and the increasing reservoir volume capacity also impacted on the water discharge over the past decades, although in different ways. The possible impacts of the Three Gorges Dam on the monthly variation of water discharge to the sea are discussed with special emphasis. In the middle basin discussions are focused on the effect of decreasing lake area, of increasing reservoir capacity, and of irrigated agriculture on the temporal changes of water discharge since the 1950s. The human impacts on water discharge from the lower basin to the sea are mostly attributed to water transfer to both tributary and neighboring drainage basins by a large number of electric pumping stations and sluices. The total water transferring capacity is more than 5000 m 3/s along the lower river. Studies indicate that in a dry season the water discharge to the sea is greatly reduced and results in strong saltwater intrusion in the estuary.

  13. Impact of climate change on river discharge in the Teteriv River basin (Ukraine)

    Science.gov (United States)

    Didovets, Iulii; Lobanova, Anastasia; Krysanova, Valentina; Snizhko, Sergiy; Bronstert, Axel

    2016-04-01

    The problem of water resources availability in the climate change context arises now in many countries. Ukraine is characterized by a relatively low availability of water resources compared to other countries. It is the 111th among 152 countries by the amount of domestic water resources available per capita. To ensure socio-economic development of the region and to adapt to climate change, a comprehensive assessment of potential changes in qualitative and quantitative characteristics of water resources in the region is needed. The focus of our study is the Teteriv River basin located in northern Ukraine within three administrative districts covering the area of 15,300 km2. The Teteriv is the right largest tributary of the Dnipro River, which is the fourth longest river in Europe. The water resources in the region are intensively used in industry, communal infrastructure, and agriculture. This is evidenced by a large number of dams and industrial objects which have been constructed from the early 20th century. For success of the study, it was necessary to apply a comprehensive hydrological model, tested in similar natural conditions. Therefore, an eco-hydrological model SWIM with the daily time step was applied, as this model was used previously for climate impact assessment in many similar river basins on the European territory. The model was set up, calibrated and validated for the gauge Ivankiv located close to the outlet of the Teteriv River. The Nash-Sutcliffe efficiency coefficient for the calibration period is 0.79 (0.86), and percent bias is 4,9% (-3.6%) with the daily (monthly) time step. The future climate scenarios were selected from the IMPRESSIONS (Impacts and Risks from High-End Scenarios: Strategies for Innovative Solutions, www.impressions-project.eu) project, which developed 7 climate scenarios under RCP4.5 and RCP8.5 based on GCMs and downscaled using RCMs. The results of climate impact assessment for the Teteriv River basin will be presented.

  14. Hydrological impact of rainwater harvesting in the Modder river basin of central South Africa

    Directory of Open Access Journals (Sweden)

    W. A. Welderufael

    2011-05-01

    Full Text Available Along the path of water flowing in a river basin are many water-related human interventions that modify the natural systems. Rainwater harvesting is one such intervention that involves harnessing of water in the upstream catchment. Increased water usage at upstream level is an issue of concern for downstream water availability to sustain ecosystem services. The upstream Modder River basin, located in a semi arid region in the central South Africa, is experiencing intermittent meteorological droughts causing water shortages for agriculture, livestock and domestic purpose. To address this problem a technique was developed for small scale farmers with the objective of harnessing rainwater for crop production. However, the hydrological impact of a wider adoption of this technique by farmers has not been well quantified. In this regard, the SWAT hydrological model was used to simulate the hydrological impact of such practices. The scenarios studied were: (1 Baseline scenario, based on the actual land use of 2000, which is dominated by pasture (combination of natural and some improved grass lands (PAST; (2 Partial conversion of Land use 2000 (PAST to conventional agriculture (Agri-CON; and (3 Partial conversion of Land use 2000 (PAST to in-field rainwater harvesting which was aimed at improving the precipitation use efficiency (Agri-IRWH.

    SWAT was calibrated using observed daily mean stream flow data of a sub-catchment (419 km2 in the study area. SWAT performed well in simulating the stream flow giving Nash and Sutcliffe (1970 efficiency index of 0.57 for the monthly stream flow calibration. The simulated water balance results showed that the highest peak mean monthly direct flow was obtained on Agri-CON land use (18 mm, followed by PAST (12 mm and Agri-IRWH land use (9 mm. These were 19 %, 13 % and 11 % of the mean annual rainfall, respectively. The Agri-IRWH scenario reduced direct flow by 38 % compared to Agri-CON. On the other

  15. Impact of climate change on sediment yield in the Mekong River Basin: a case study of the Nam Ou Basin, Lao PDR

    Directory of Open Access Journals (Sweden)

    B. Shrestha

    2012-03-01

    Full Text Available This paper evaluates the impact of climate change on sediment yield in the Nam Ou Basin located in Northern Laos. The Soil and Water Assessment Tool (SWAT is used to assess future changes in sediment flux attributable to climate change. Future precipitation and temperature series are constructed through a delta change approach. As per the results, in general, temperature as well as precipitation show increasing trends in both scenarios, A2 and B2. However, monthly precipitation shows both increasing and decreasing trends. The simulation results exhibit that the wet and dry seasonal and annual stream discharges are likely to increase (by up to 15, 17 and 14% under scenario A2; and 11, 5 and 10% under scenario B2 respectively in the future, which will lead to increased wet and dry seasonal and annual sediment yields (by up to 39, 28 and 36% under scenario A2; and 23, 12 and 22% under scenario B2 respectively. A higher discharge and more sediment flux are expected during the wet seasons, although the changes, percentage-wise, are observed to be higher during the dry months. In conclusion, the sediment yield from the Nam Ou Basin is likely to increase with climate change, which strongly suggests the need for basin-wide sediment management strategies in order to reduce the negative impact of this change.

  16. Climate change impact on soil erosion in the Mandakini River Basin, North India

    Science.gov (United States)

    Khare, Deepak; Mondal, Arun; Kundu, Sananda; Mishra, Prabhash Kumar

    2017-09-01

    Correct estimation of soil loss at catchment level helps the land and water resources planners to identify priority areas for soil conservation measures. Soil erosion is one of the major hazards affected by the climate change, particularly the increasing intensity of rainfall resulted in increasing erosion, apart from other factors like landuse change. Changes in climate have an adverse effect with increasing rainfall. It has caused increasing concern for modeling the future rainfall and projecting future soil erosion. In the present study, future rainfall has been generated with the downscaling of GCM (Global Circulation Model) data of Mandakini river basin, a hilly catchment in the state of Uttarakhand, India, to obtain future impact on soil erosion within the basin. The USLE is an erosion prediction model designed to predict the long-term average annual soil loss from specific field slopes in specified landuse and management systems (i.e., crops, rangeland, and recreational areas) using remote sensing and GIS technologies. Future soil erosion has shown increasing trend due to increasing rainfall which has been generated from the statistical-based downscaling method.

  17. Climate change impact on soil erosion in the Mandakini River Basin, North India

    Science.gov (United States)

    Khare, Deepak; Mondal, Arun; Kundu, Sananda; Mishra, Prabhash Kumar

    2016-05-01

    Correct estimation of soil loss at catchment level helps the land and water resources planners to identify priority areas for soil conservation measures. Soil erosion is one of the major hazards affected by the climate change, particularly the increasing intensity of rainfall resulted in increasing erosion, apart from other factors like landuse change. Changes in climate have an adverse effect with increasing rainfall. It has caused increasing concern for modeling the future rainfall and projecting future soil erosion. In the present study, future rainfall has been generated with the downscaling of GCM (Global Circulation Model) data of Mandakini river basin, a hilly catchment in the state of Uttarakhand, India, to obtain future impact on soil erosion within the basin. The USLE is an erosion prediction model designed to predict the long-term average annual soil loss from specific field slopes in specified landuse and management systems (i.e., crops, rangeland, and recreational areas) using remote sensing and GIS technologies. Future soil erosion has shown increasing trend due to increasing rainfall which has been generated from the statistical-based downscaling method.

  18. Multi-model assessment of hydrologic impacts of climate change in a small Mediterranean basin

    Science.gov (United States)

    Perra, Enrica; Piras, Monica; Deidda, Roberto; Paniconi, Claudio; Mascaro, Giuseppe; Vivoni, Enrique R.; Cau, Pierluigi; Marras, Pier Andrea; Meyer, Swen; Ludwig, Ralf

    2017-04-01

    Assessing the hydrologic impacts of climate change is of great importance in the Mediterranean region, which is characterized by high precipitation variablitity and complex interactions within the water cycle. In this work we focus on the hydrological response of the Rio Mannu catchment, a small basin located in southern Sardinia (Italy) and characterized by a semi-arid climate. Specifically, we investigate inter-model variability and uncertainty by comparing the results of five distributed hydrologic models, namely CATchment HYdrology (CATHY), Soil and Water Assessment Tool (SWAT), TOPographic Kinematic APproximation and Integration eXtended (TOPKAPI-X), TIN-based Real time Integrated Basin Simulator (tRIBS), and WAter flow and balance SIMulation (WASIM), that differ greatly in their representation of terrain features, physical processes, and numerical complexity. The hydrological models were independently calibrated and validated on observed meteorological and hydrological time series, and then forced by the output of four combinations of global and regional climate models (properly bias-corrected and downscaled) in order to evaluate the effects of climate change for a reference (1971-2000) and a future (2041-2070) period. Notwithstanding their differences, the five hydrologic models responded similarly to the reduced precipitation and increased temperatures predicted by the climate models, and lend strong support to a future scenario of increased water shortages. The multi-model framework allows estimation of the uncertainty associated with these hydrologic simulations and this aspect will also be discussed.

  19. Continental impacts of water development on waterbirds, contrasting two Australian river basins: Global implications for sustainable water use.

    Science.gov (United States)

    Kingsford, Richard T; Bino, Gilad; Porter, John L

    2017-06-04

    The world's freshwater biotas are declining in diversity, range and abundance, more than in other realms, with human appropriation of water. Despite considerable data on the distribution of dams and their hydrological effects on river systems, there are few expansive and long analyses of impacts on freshwater biota. We investigated trends in waterbird communities over 32 years, (1983-2014), at three spatial scales in two similarly sized large river basins, with contrasting levels of water resource development, representing almost a third (29%) of Australia: the Murray-Darling Basin and the Lake Eyre Basin. The Murray-Darling Basin is Australia's most developed river basin (240 dams storing 29,893 GL) while the Lake Eyre Basin is one of the less developed basins (1 dam storing 14 GL). We compared the long-term responses of waterbird communities in the two river basins at river basin, catchment and major wetland scales. Waterbird abundances were strongly related to river flows and rainfall. For the developed Murray-Darling Basin, we identified significant long-term declines in total abundances, functional response groups (e.g., piscivores) and individual species of waterbird (n = 50), associated with reductions in cumulative annual flow. These trends indicated ecosystem level changes. Contrastingly, we found no evidence of waterbird declines in the undeveloped Lake Eyre Basin. We also modelled the effects of the Australian Government buying up water rights and returning these to the riverine environment, at a substantial cost (>3.1 AUD billion) which were projected to partly (18% improvement) restore waterbird abundances, but projected climate change effects could reduce these benefits considerably to only a 1% or 4% improvement, with respective annual recovery of environmental flows of 2,800 GL or 3,200 GL. Our unique large temporal and spatial scale analyses demonstrated severe long-term ecological impact of water resource development on prominent

  20. Assessing Hydrologic Impacts of Future Land Cover Change Scenarios in the South Platte River Basin (CO, WY, & NE) and the San Pedro River Basin (U.S./Mexico).

    Science.gov (United States)

    Barlow, J. E.; Burns, I. S.; Guertin, D. P.; Kepner, W. G.; Goodrich, D. C.

    2016-12-01

    Long-term land-use and land cover change and their associated impacts pose critical challenges to sustaining vital hydrological ecosystem services for future generations. In this study, a methodology to characterize hydrologic impacts from future urban growth through time that was developed and applied on the San Pedro River Basin was expanded and utilized on the South Platte River Basin as well. Future urban growth is represented by housing density maps generated in decadal intervals from 2010 to 2100, produced by the U.S. Environmental Protection Agency (EPA) Integrated Climate and Land-Use Scenarios (ICLUS) project. ICLUS developed future housing density maps by adapting the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) social, economic, and demographic storylines to the conterminous United States. To characterize hydrologic impacts from future growth, the housing density maps were reclassified to National Land Cover Database (NLCD) 2006 land cover classes and used to parameterize the Soil and Water Assessment Tool (SWAT) using the Automated Geospatial Watershed Assessment (AGWA) tool. The objectives of this project were to 1) develop and implement a methodology for adapting the ICLUS data for use in AGWA as an approach to evaluate impacts of development on water-quantity and -quality, 2) present, evaluate, and compare results from scenarios for watersheds in two different geographic and climatic regions, 3) determine watershed specific implications of this type of future land cover change analysis.

  1. Climate Change Impacts on Water Resources in Mahanadi River basin (India)

    Science.gov (United States)

    Lilhare, R.; Mishra, V.

    2014-12-01

    Streamflow estimation using hydrological modeling and assessing the impact of climate change on it can increasingly help in dealing with the challenges that water resource managers and planners. In the present study, continuous distributed hydrological model named Soil and Water Assessment Tool (SWAT) is used for streamflow estimation at five gauging stations within Mahanadi river basin, Orissa, India. Further streamflow response to climate change has been examined. For this, the SWAT model has been first calibrated and validated for the period of 1951-2007. Then, with the aim of evaluating the impact of climate change on the basin hydrology for the period of 2010-2099, downscaled and bias corrected data from the CMIP5 (Coupled Model Intercomparison Project) models (i.e. bcc-csm1-1, inmcm4, mpi-esm-Ir, mri-cgcm3 and noresm1-m) under the RCP 4.5 and RCP 8.5 scenarios were used to derive the SWAT model. We find that streamflow variations are more sensitive to changing climate in the monsoon (JJAS) and pre-monsoon (FMAM) seasons than that of the post-monsoon season. Moreover, simulated runoff for the projected period (2010-2099) was found to be changing in a range of -17 to 59% in the monsoon, -18 to 65% in the post-monsoon, -76 to 451% in pre-monsoon under the RCP 4.5 scenario and for the RCP 8.5 streamflow changes have been assessed between -5 to 107% in monsoon, -0.45 to 105% in post-monsoon, -61 to 202% in pre-monsoon period. Keywords: SWAT; Climate Change; CMIP; RCP; Mahanadi

  2. Impact of deforestation on local precipitation patterns over the Da River basin, Vietnam

    Science.gov (United States)

    Anghileri, Daniela; Spartà, Daniele; Castelletti, Andrea; Boschetti, Mirco

    2014-05-01

    Change in land cover, e.g. from forest to bare soil, might severely impact the hydrological cycle at the river basin scale by altering the balance between rainfall and evaporation, ultimately affecting streamflow dynamics. These changes generally occur over decades, but they might be much more rapid in developing countries, where economic growth and growing population may cause abrupt changes in landscape and ecosystem. Detecting, analysing and modelling these changes is an essential step to design mitigation strategies and adaptation plans, balancing economic development and ecosystem protection. In this work we investigate the impact of land cover changes on the water cycle in the Da River basin, Vietnam. More precisely, the objective is to evaluate the interlink between deforestation and precipitation. The case study is particularly interesting because Vietnam is one of the world fastest growing economies and natural resources have been considerably exploited to support after-war development. Vietnam has the second highest rate of deforestation of primary forests in the world, second to only Nigeria (FAO 2005), with associated problems like abrupt change in run-off, erosion, sediment transport and flash floods. We performed land cover evaluation by combining literature information and Remote Sensing techniques, using Landsat images. We then analysed time series of precipitation observed on the period 1960-2011 in several stations located in the catchment area. We used multiple trend detection techniques, both state-of-the-art (e.g., Linear regression and Mann-Kendall) and novel trend detection techniques (Moving Average on Shifting Horizon), to investigate trends in seasonal pattern of precipitation. Results suggest that deforestation may induce a negative trend in the precipitation volume. The effect is mainly recognizable at the beginning and at the end of the monsoon season, when the local mechanisms of precipitation formation prevail over the large scale

  3. Hydrologic impacts of climate change on the Nile River basin: Implications of the 2007 IPCC climate scenarios

    NARCIS (Netherlands)

    Beyene, T.; Lettenmaier, D.P.; Kabat, P.

    2010-01-01

    We assess the potential impacts of climate change on the hydrology and water resources of the Nile River basin using a macroscale hydrology model. Model inputs are bias corrected and spatially downscaled 21st Century simulations from 11 General Circulation Models (GCMs) and two global emissions scen

  4. Investigation of the hydrological Impact of Land-use Change in the Zanjanrood Basin, North-West Iran

    NARCIS (Netherlands)

    Ghaffari, G.; Ghodousi, J.; Ahmadi, H.; Keesstra, S.D.

    2010-01-01

    Understanding the impacts of land-use changes on hydrology at the watershed scale can facilitate development of sustainable water resource strategies. This paper investigates the hydrological effects of land-use change in Zanjanrood basin, Iran. The water balance was simulated using the Soil and Wat

  5. Win-wins in NTFP market chains? How governance impacts the sustainability of livelihoods based on Congo Basin forest products

    NARCIS (Netherlands)

    Ingram, V.J.

    2012-01-01

    Exploring the interrelationships between governance, poverty alleviation and sustainability impacts in the framework of market chains for non-timber forest products originating from the Congo Basin. The research focuses on how governance arrangements help or hinder access to forest resources and the

  6. Assessing Hydrologic Impacts of Future Land Cover Change Scenarios in the South Platte River Basin (CO, WY, & NE)

    Science.gov (United States)

    Long‐term land‐use and land cover change and their associated impacts pose critical challenges to sustaining vital hydrological ecosystem services for future generations. In this study, a methodology was developed on the San Pedro River Basin to characterize hydrologi...

  7. A Very Large Population of Likely Buried Impact Basins in the Northern Lowlands of Mars Revealed by MOLA Data

    Science.gov (United States)

    Frey, H. V.; Shockey, K. M.; Frey, E. L.; Roark, J. H.; Sakimoto, S. E. H.

    2001-01-01

    High resolution Mars Orbiter Laser Altimeter (MOLA) data have revealed a large number of subdued quasi-circular depressions (QCDs) >50 km diameter in the northern lowlands of Mars which are generally not visible in Viking imagery and which may be buried ancient impact basins. Additional information is contained in the original extended abstract.

  8. Win-wins in NTFP market chains? How governance impacts the sustainability of livelihoods based on Congo Basin forest products

    NARCIS (Netherlands)

    Ingram, V.J.

    2012-01-01

    Exploring the interrelationships between governance, poverty alleviation and sustainability impacts in the framework of market chains for non-timber forest products originating from the Congo Basin. The research focuses on how governance arrangements help or hinder access to forest resources and

  9. Assessing Hydrologic Impacts of Future Land Cover Change Scenarios in the South Platte River Basin (CO, WY, & NE)

    Science.gov (United States)

    Long‐term land‐use and land cover change and their associated impacts pose critical challenges to sustaining vital hydrological ecosystem services for future generations. In this study, a methodology was developed on the San Pedro River Basin to characterize hydrologi...

  10. Resilience landscapes for Congo basin rainforests vs. climate and management impacts

    Science.gov (United States)

    Pietsch, Stephan Alexander; Gautam, Sishir; Elias Bednar, Johannes; Stanzl, Patrick; Mosnier, Aline; Obersteiner, Michael

    2015-04-01

    Past climate change caused severe disturbances of the Central African rainforest belt, with forest fragmentation and re-expansion due to drier and wetter climate conditions. Besides climate, human induced forest degradation affected biodiversity, structure and carbon storage of Congo basin rainforests. Information on climatically stable, mature rainforest, unaffected by human induced disturbances, provides means of assessing the impact of forest degradation and may serve as benchmarks of carbon carrying capacity over regions with similar site and climate conditions. BioGeoChemical (BGC) ecosystem models explicitly consider the impacts of site and climate conditions and may assess benchmark levels over regions devoid of undisturbed conditions. We will present a BGC-model validation for the Western Congolian Lowland Rainforest (WCLRF) using field data from a recently confirmed forest refuge, show model - data comparisons for disturbed und undisturbed forests under different site and climate conditions as well as for sites with repeated assessment of biodiversity and standing biomass during recovery from intensive exploitation. We will present climatic thresholds for WCLRF stability, and construct resilience landscapes for current day conditions vs. climate and management impacts.

  11. Impact of basin scale and time-weighted mercury metrics on intra-/inter-basin mercury comparisons

    Science.gov (United States)

    Paul Bradley; Mark E. Brigham

    2016-01-01

    Understanding anthropogenic and environmental controls on fluvial Mercury (Hg) bioaccumulation over global and national gradients can be challenging due to the need to integrate discrete-sample results from numerous small scale investigations. Two fundamental issues for such integrative Hg assessments are the wide range of basin scales for included studies and how well...

  12. Uncertainties in assessing climate change impacts on the hydrology of Mediterranean basins

    Science.gov (United States)

    Ludwig, Ralf

    2013-04-01

    There is substantial evidence in historical and recent observations that the Mediterranean and neighboring regions are especially vulnerable to the impacts of climate change. Numerous climate projections, stemming from ensembles of global and regional climate models, agree on severe changes in the climate forcing which are likely to exacerbate subsequent ecological, economic and social impacts. Many of these causal connections are closely linked to the general expectation that water availability will decline in the already water-stressed basins of Africa, the Mediterranean region and the Near East, even though considerable regional variances must be expected. Consequently, climate change impacts on water resources are raising concerns regarding their possible management and security implications. Decreasing access to water resources and other related factors could be a cause or a 'multiplier' of tensions within and between countries. Whether security threats arise from climate impacts or options for cooperation evolve does not depend only on the severity of the impacts themselves, but on social, economic, and institutional vulnerabilities or resilience as well as factors that influence local, national and international relations. However, an assessment of vulnerability and risks hinges on natural, socio-economic, and political conditions and responses, all of which are uncertain. Multidisciplinary research is needed to tackle the multi-facet complexity of climate change impacts on water resources in the Mediterranean and neighboring countries. This is particularly true in a region of overall data scarcity and poor data management and exchange structures. The current potential to develop appropriate regional adaptation measures towards climate change impacts suffers heavily from large uncertainties. These spread along a long chain of components, starting from the definition of emission scenarios to global and regional climate modeling to impact models and a

  13. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Directory of Open Access Journals (Sweden)

    Ling Zhang

    Full Text Available Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014 and near future (2015-2024, by combining two land use models (i.e., Markov chain model and Dyna-CLUE with a hydrological model (i.e., SWAT. The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  14. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    Science.gov (United States)

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  15. Multi-Model CIMP5 projected impacts of increased greenhouse gases on the Niger basin and implications for hydropower production

    Science.gov (United States)

    Oyerinde, Ganiyu; Wisser, Dominik

    2014-05-01

    Climate change could potentially have large impacts on water availability in West Africa and the predictions are accrued with high uncertainties in this region. Countries in the Niger River basin (West Africa) plan the investment of 200 million in the installation of an additional 400MW of hydropower in the nearest future, adding to the existing 685MW. With the impacts of climate change in the basin already occurring, there is a need for comprehending the influence of future hydro-climatic changes on water resources and hydro-power generation in the basin. This study uses a hydrological model to simulate river flow under present and future conditions and evaluates the impacts of potential changes on electricity production of the largest hydroelectric dam (Kainji) in the Niger Basin. The Kainji reservoir produces 25 per cent of the current energy needs of Nigeria and was subject to large fluctuations in energy production as a result of variable inflow and operational reasons. Inflow into the reservoir was simulated using hydroclimatic data from a set of 7 regional climate models (RCM) with two emission scenarios from the CORDEX-Africa regional downscaling experiment, driven with CMIP5 data. Based on observations of inflow, water level in the reservoir, and energy production we developed a simple hydroelectricity production model to simulate future energy production for the reservoir. Results suggest increases in river flow for the majority of RCM data as a result of increases in precipitation in the headwaters of the basin around 2050 and slightly decreasing trends for low emission scenarios by the end of the century. Despite this consistent increase, shifts in timing of river flow can challenge the reliable production of energy. This analysis could help assess the planning of hydropower schemes in the basin for a sustainable production of hydroelectricity in the future.

  16. Dealing with uncertainties in impact studies of climate change on hydrometeorological series over Segura River Basin (Spain)

    Science.gov (United States)

    Garcia Galiano, S. G.; Garcia Cardenas, R.; Tetay Botia, C.; Giraldo Osorio, J.; Erena Arrabal, M.; Baille, A.

    2011-12-01

    The Segura River Basin (SRB) located in the South East of Spain, is affected by recurrent drought and water scarcity episodes. This basin presents the lowest percentage of renewable water resources of all the Spanish basins. Intensive reforestation has been carried out in the region, to halt desertification and erosion, which added to climate change and variability, do not allow the default assumption of stationarity in the water resources systems. Therefore, the study of effects in hydrometeorological series should be addressed by nonstationary probabilistic models that allow describing the time evolution of their probability distribution functions (PDFs). In the present work, the GAMLSS (Generalized Additive Models for Location, Scale and Shaper) approach is applied to identify of spatio-temporal trends in observed precipitation (P) and potential evapotranspiration (PET), at basin scale. Several previous studies have addressed the potential impacts of climate change in water supply systems, focusing on the sensitivity analysis of runoff to climate. Considering the use of a conceptual hydrological model with few parameters, the impacts on runoff and its trend from historical data, are assessed. The conclusions of this study represent a breakthrough in the development of methodologies to understand and anticipate the impacts on water resources systems, in the light of current and future climate conditions, considering hydroclimatic non-stationarity. These findings are expected to contribute to the management of conditions of water resources scarcity and droughts, such as the observed in the SRB, as support to decision-making process by stakeholders.

  17. Impact of subsurface drainage on streamflows in the Red River of the North basin

    Science.gov (United States)

    Rahman, Mohammed M.; Lin, Zhulu; Jia, Xinhua; Steele, Dean D.; DeSutter, Thomas M.

    2014-04-01

    The debate about subsurface drainage effects on streamflows has been reignited in the Red River of the North basin in North America, after a decades-long abnormally wet weather pattern in the region. Our study evaluated the applicability of the Soil and Water Assessment Tool (SWAT) in modeling subsurface drainage in a cold environment; we then employed streamflow response analyses to assess the potential impacts of the extensive subsurface drainage development in the Red River Valley (RRV) on streamflows in the Red River. The results showed that extensive subsurface drainage in the RRV would likely increase the magnitude of smaller peak flows while decreasing the magnitude of larger peak flows. Discharge reduction of large peak flows was mainly caused by reducing the flow volumes rather than increasing the time-to-peak of the hydrograph. Our analysis also suggested that extensive subsurface drainage could move more water from the watershed to the rivers in the fall season, creating more storage capacity in the soils. However, such increase in storage capacity in soils would have a negligible effect in reducing the monthly flow volumes in the following spring. The proposed method of coupling a watershed model with streamflow response analysis can be readily adopted by other researchers to evaluate the streamflow impact of land-use and climate changes around the world.

  18. Possible Future Climate Change Impacts on the Hydrological Drought Events in the Weihe River Basin, China

    Directory of Open Access Journals (Sweden)

    Fei Yuan

    2016-01-01

    Full Text Available Quantitative evaluation of future climate change impacts on hydrological drought characteristics is one of important measures for implementing sustainable water resources management and effective disaster mitigation in drought-prone regions under the changing environment. In this study, a modeling system for projecting the potential future climate change impacts on hydrological droughts in the Weihe River basin (WRB in North China is presented. This system consists of a large-scale hydrological model driven by climate outputs from three climate models (CMs for future streamflow projections, a probabilistic model for univariate drought assessment, and a copula-based bivariate model for joint drought frequency analysis under historical and future climates. With the observed historical climate data as the inputs, the Variable Infiltration Capacity hydrological model projects an overall runoff reduction in the WRB under the Intergovernmental Panel on Climate Change A1B scenario. The univariate drought assessment found that although fewer hydrological drought events would occur under A1B scenario, drought duration and severity tend to increase remarkably. Moreover, the bivariate drought assessment reveals that future droughts in the same return period as the baseline droughts would become more serious. With these trends in the future, the hydrological drought situation in the WRB would be further deteriorated.

  19. Simulation modeling of hydropower impacts on dissolved oxygen in the upper Ohio river basin

    Energy Technology Data Exchange (ETDEWEB)

    Railsback, S.F.; Jager, H.I.

    1988-09-01

    A model has been developed to assess the impacts of hydropower development at navigation dams on dissolved oxygen (DO) concentrations in the upper Ohio River basin. Field data were used to fit statistical models of aeration at each dam. The Streeter-Phelps equations were used to model DO concentrations between dams. Input data sources were compiled, and the design conditions used for assessment of hydropower impacts were developed. The model was implemented both as Lotus 1-2-3 spreadsheets and as a FORTRAN program. This report contains users' guides for both of these implementations. The sensitivities and uncertainty of the model were analyzed. Modeled DO concentrations are sensitive to water temperature and flow rates, and sensitivities to dam aeration are relatively high in reaches where dam aeration rates are high. Uncertainty in the model was low in reaches dominated by dam aeration and higher in reaches with low dam aeration rates. The 95% confidence intervals for the model range from about /+-/ 0.5 mg/L to about /+-/ 1.5 mg/L.

  20. Climate Change Impacts on US Water Quality Using Two Models: HAWQS and US Basins

    Directory of Open Access Journals (Sweden)

    Charles Fant

    2017-02-01

    Full Text Available Climate change and freshwater quality are well-linked. Changes in climate result in changes in streamflow and rising water temperatures, which impact biochemical reaction rates and increase stratification in lakes and reservoirs. Using two water quality modeling systems (the Hydrologic and Water Quality System; HAWQS and US Basins, five climate models, and two greenhouse gas (GHG mitigation policies, we assess future water quality in the continental U.S. to 2100 considering four water quality parameters: water temperature, dissolved oxygen, total nitrogen, and total phosphorus. Once these parameters are aggregated into a water quality index, we find that, while the water quality models differ under the baseline, there is more agreement between future projections. In addition, we find that the difference in national-scale economic benefits across climate models is generally larger than the difference between the two water quality models. Both water quality models find that water quality will more likely worsen in the East than in the West. Under the business-as-usual emissions scenario, we find that climate change is likely to cause economic impacts ranging from 1.2 to 2.3 (2005 billion USD/year in 2050 and 2.7 to 4.8 in 2090 across all climate and water quality models.

  1. Climate change and land-use change impact on Western African river basins

    Science.gov (United States)

    Mariotti, Laura; Coppola, Erika; Giorgi, Filippo

    2010-05-01

    The main resource in western Africa is agriculture and therefore availability and quality of fresh water resources threaten food production in many regions. Quantifying the impact of climate and land-use change in very vulnerable regions like western Africa is therefore of crucial importance for developing appropriate adaptation and mitigation strategies. In this work the International Center for theoretical Physic (ICTP) regional climate model (RegCM3) is used to perform a 120 (1980-2100) years climate change simulation under the A1B scenario using ECHAM5 as boundary condition (BC). To further investigate which it would be the combined effect of the land-use change together with the climate change a 10 years time simulation has been completed using the future projected land-use from IIASA (The International Institute for Applied Systems Analysis). Both simulations have been coupled with a physical based fully distributed hydrological model (CHyM) to asses which it would be the final effect of climate and land-use change on the river discharge. The two rivers used for this analysis are the Niger and Volta basin. The CHyM model has been validated coupling fist the hydrological model with a perfect boundary regional model simulation using ERA-interim as BC and using the runoff observations available along the two river basins. The model is able to reproduce the monthly seasonal cycle in both river basins reasonably well, therefore this allow us to use the same setting for a climate and land-use change simulation. Two hydrological time slice simulations have been performed with and without land-use change included. Results are presented and discussed for the monsoon season (JJA) on a station based, for the same stations used for validation purposed, but also the spatial change in discharge is presented in both cases and compared with the simple precipitation change observed in the region. Although the portion of change in precipitation due to the green house gases

  2. Climate change impact on the management of water resources in the Seine River basin, France

    Science.gov (United States)

    Dorchies, David; Thirel, Guillaume; Chauveau, Mathilde; Jay-Allemand, Maxime; Perrin, Charles; Dehay, Florine

    2013-04-01

    annual flows were assessed under natural condition (i.e. without the inclusion of the reservoirs in the models). Then, the impact of reservoirs and their management were accounted for in the modeling chain. Results will be discussed relatively to future hydro-climatic conditions and current mitigation objectives within the basin. Reference: Pagé, C., L. Terray et J. Boé, 2009: dsclim: A software package to downscale climate scenarios at regional scale using a weather-typing based statistical methodology. Technical Report TR/CMGC/09/21, SUC au CERFACS, URA CERFACS/CNRS No1875, Toulouse, France. Link : http://www.cerfacs.fr/~page/dsclim/dsclim_doc-latest.pdf

  3. Impacts of biofuels production alternatives on water quantity and quality in the Iowa River Basin

    Science.gov (United States)

    Wu, Y.; Liu, S.

    2012-01-01

    Corn stover as well as perennial grasses like switchgrass (Panicum virgatum) and miscanthus are being considered as candidates for the second generation biofuel feedstocks. However, the challenges to biofuel development are its effects on the environment, especially water quality. This study evaluates the long-term impacts of biofuel production alternatives (e.g., elevated corn stover removal rates and the potential land cover change) on an ecosystem with a focus on biomass production, soil erosion, water quantity and quality, and soil nitrate nitrogen concentration at the watershed scale. The Soil and Water Assessment Tool (SWAT) was modified for setting land cover change scenarios and applied to the Iowa River Basin (a tributary of the Upper Mississippi River Basin). Results show that biomass production can be sustained with an increased stover removal rate as long as the crop demand for nutrients is met with appropriate fertilization. Although a drastic increase (4.7–70.6%) in sediment yield due to erosion and a slight decrease (1.2–3.2%) in water yield were estimated with the stover removal rate ranging between 40% and 100%, the nitrate nitrogen load declined about 6–10.1%. In comparison to growing corn, growing either switchgrass or miscanthus can reduce sediment erosion greatly. However, land cover changes from native grass to switchgrass or miscanthus would lead to a decrease in water yield and an increase in nitrate nitrogen load. In contrast to growing switchgrass, growing miscanthus is more productive in generating biomass, but its higher water demand may reduce water availability in the study area.

  4. Climate change impacts on streamflow and subbasin-scale hydrology in the Upper Colorado River Basin.

    Directory of Open Access Journals (Sweden)

    Darren L Ficklin

    Full Text Available In the Upper Colorado River Basin (UCRB, the principal source of water in the southwestern U.S., demand exceeds supply in most years, and will likely continue to rise. While General Circulation Models (GCMs project surface temperature warming by 3.5 to 5.6°C for the area, precipitation projections are variable, with no wetter or drier consensus. We assess the impacts of projected 21(st century climatic changes on subbasins in the UCRB using the Soil and Water Assessment Tool, for all hydrologic components (snowmelt, evapotranspiration, surface runoff, subsurface runoff, and streamflow, and for 16 GCMs under the A2 emission scenario. Over the GCM ensemble, our simulations project median Spring streamflow declines of 36% by the end of the 21(st century, with increases more likely at higher elevations, and an overall range of -100 to +68%. Additionally, our results indicated Summer streamflow declines with median decreases of 46%, and an overall range of -100 to +22%. Analysis of hydrologic components indicates large spatial and temporal changes throughout the UCRB, with large snowmelt declines and temporal shifts in most hydrologic components. Warmer temperatures increase average annual evapotranspiration by ∼23%, with shifting seasonal soil moisture availability driving these increases in late Winter and early Spring. For the high-elevation water-generating regions, modest precipitation decreases result in an even greater water yield decrease with less available snowmelt. Precipitation increases with modest warming do not translate into the same magnitude of water-yield increases due to slight decreases in snowmelt and increases in evapotranspiration. For these basins, whether modest warming is associated with precipitation decreases or increases, continued rising temperatures may make drier futures. Subsequently, many subbasins are projected to turn from semi-arid to arid conditions by the 2080 s. In conclusion, water availability in the UCRB

  5. Impact of climate change on hydrological behaviour and crop production in a glacial river basin

    Science.gov (United States)

    Remesan, Renji; Holman, Ian; Janes, Victoria

    2015-04-01

    Himalayan valleys are confronting severe climate change related issues (flash flood and landslides, water scarcity in higher altitudes) because of fluctuating monsoon precipitation and increasing seasonal temperatures. In this study, the Soil and Water Assessment Tool (SWAT) model has been applied to the River Beas basin, using daily Tropical Rainfall Measuring Mission (TRMM) precipitation and NCEP Climate Forecast System Reanalysis (CFSR) meteorological data to simulate the river regime and crop yields. The Beas is regionally significant as it holds two giant dams, one which annually diverts 4700 Mm3 of water to a nearby basin. We have applied Sequential Uncertainty Fitting Ver. 2 (SUFI-2) to quantify the parameter uncertainty of the stream flow modelling. The model evaluation statistics for Daily River flows at the Jwalamukhi and Pong gauges show good agreement with measured flows (Nash Sutcliffe efficiency of 0.70 and PBIAS of 7.54 %). We then applied the models within a scenario-neutral framework to develop hydrological and crop yield Impact Response Surfaces (IRS) for future changes in annual temperature and precipitation for the region from AR5. Future Q10 and Q90 daily flows indicate amplified 'flash flood' situations and increased low flows, respectively, with increasing temperatures due to increased snowmelt from retreating glaciers. Under existing crop and irrigation management practices, the IRS show decreasing and increasing crop yields for summer (monsoon) and winter (post monsoon) crops, respectively, with rising temperature. The sensitivity of winter (post monsoon) crop yields to precipitation increases with increasing temperature. The paper will consider the implications of the research for future agricultural water management and the potential of agronomic and irrigation adaptation to offset yield losses

  6. Impact of state updating and multi-parametric ensemble for streamflow hindcasting in European river basins

    Science.gov (United States)

    Noh, S. J.; Rakovec, O.; Kumar, R.; Samaniego, L. E.

    2015-12-01

    Accurate and reliable streamflow prediction is essential to mitigate social and economic damage coming from water-related disasters such as flood and drought. Sequential data assimilation (DA) may facilitate improved streamflow prediction using real-time observations to correct internal model states. In conventional DA methods such as state updating, parametric uncertainty is often ignored mainly due to practical limitations of methodology to specify modeling uncertainty with limited ensemble members. However, if parametric uncertainty related with routing and runoff components is not incorporated properly, predictive uncertainty by model ensemble may be insufficient to capture dynamics of observations, which may deteriorate predictability. Recently, a multi-scale parameter regionalization (MPR) method was proposed to make hydrologic predictions at different scales using a same set of model parameters without losing much of the model performance. The MPR method incorporated within the mesoscale hydrologic model (mHM, http://www.ufz.de/mhm) could effectively represent and control uncertainty of high-dimensional parameters in a distributed model using global parameters. In this study, we evaluate impacts of streamflow data assimilation over European river basins. Especially, a multi-parametric ensemble approach is tested to consider the effects of parametric uncertainty in DA. Because augmentation of parameters is not required within an assimilation window, the approach could be more stable with limited ensemble members and have potential for operational uses. To consider the response times and non-Gaussian characteristics of internal hydrologic processes, lagged particle filtering is utilized. The presentation will be focused on gains and limitations of streamflow data assimilation and multi-parametric ensemble method over large-scale basins.

  7. Climate change impacts on streamflow and subbasin-scale hydrology in the Upper Colorado River Basin.

    Science.gov (United States)

    Ficklin, Darren L; Stewart, Iris T; Maurer, Edwin P

    2013-01-01

    In the Upper Colorado River Basin (UCRB), the principal source of water in the southwestern U.S., demand exceeds supply in most years, and will likely continue to rise. While General Circulation Models (GCMs) project surface temperature warming by 3.5 to 5.6°C for the area, precipitation projections are variable, with no wetter or drier consensus. We assess the impacts of projected 21(st) century climatic changes on subbasins in the UCRB using the Soil and Water Assessment Tool, for all hydrologic components (snowmelt, evapotranspiration, surface runoff, subsurface runoff, and streamflow), and for 16 GCMs under the A2 emission scenario. Over the GCM ensemble, our simulations project median Spring streamflow declines of 36% by the end of the 21(st) century, with increases more likely at higher elevations, and an overall range of -100 to +68%. Additionally, our results indicated Summer streamflow declines with median decreases of 46%, and an overall range of -100 to +22%. Analysis of hydrologic components indicates large spatial and temporal changes throughout the UCRB, with large snowmelt declines and temporal shifts in most hydrologic components. Warmer temperatures increase average annual evapotranspiration by ∼23%, with shifting seasonal soil moisture availability driving these increases in late Winter and early Spring. For the high-elevation water-generating regions, modest precipitation decreases result in an even greater water yield decrease with less available snowmelt. Precipitation increases with modest warming do not translate into the same magnitude of water-yield increases due to slight decreases in snowmelt and increases in evapotranspiration. For these basins, whether modest warming is associated with precipitation decreases or increases, continued rising temperatures may make drier futures. Subsequently, many subbasins are projected to turn from semi-arid to arid conditions by the 2080 s. In conclusion, water availability in the UCRB could

  8. Impacts of extreme climate on simulated runoff in the Yellow River Basin

    Science.gov (United States)

    Tang, Y.; Tang, Q.

    2011-12-01

    Historical observations show that extreme climate events have increased in frequency in the Yellow River Basin. The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR4) projects higher climate variability in a warmer climate, suggesting an increase of extreme climate frequency in the 21st century. The responses of available water resources to the extreme climate remain relatively unexplored in the Yellow River Basin. This study examines the change in the climate extreme and its impacts on streamflow using a long time series of runoff estimated from the Soil and Water Assessment Tool (SWAT) model. The linear regression and the Mann-Kendall non-parameter statistical method are used to detect the change trend in climate (primary precipitation and temperature) extreme frequency and intensity. Three SWAT simulations are conducted. The first simulation is a control SWAT experiment using the observed climate data. The second simulation is driven by a de-trended climate data in which the linear trend is removed and the mean values are fixed to the means of the first decade. The third simulation is a stable simulation where climate conditions repeated from the first decade. The trends of the simulated runoff are analyzed and compared. The effects of changes in the temporal climate pattern and mean climate condition are computed from the estimated runoff trends. The differences between the SWAT simulations represent the contribution of the change to the alteration of the simulated runoff. Our preliminary results suggest that the extreme precipitation has significantly changed the simulated runoff both in the flow frequency and mean value.

  9. Spatiotemporal Impacts of Climate, Land Cover Change and Direct Human Activities on Runoff Variations in the Wei River Basin, China

    Directory of Open Access Journals (Sweden)

    Yunyun Li

    2016-05-01

    Full Text Available Previous studies that quantified variations in runoff have mainly focused on the combined impacts of climate and human activities or climate and land cover change. Few have separated land cover change from human activities, which is critical for effective management of water resources. This study aims to investigate the impact of changing environmental conditions on runoff using the Soil and Water Assessment Tool (SWAT model; we examined three categories: climate, land cover change and direct human activities. The study area was the Wei River Basin, a typical arid to semi-arid basin that was divided into five sub-zones (UZ, MZ, DZ, JZ and BZ. Our results showed the following: (1 the calibrated SWAT model produced satisfactory monthly flow processes over the baseline period from 1978 to 1986; (2 compared to the baseline period, the impact of climatic variations decreased and the impact of direct human activities increased from the 1990s to the 2000s, while the impact of land cover change was generally stable; and (3 climatic variations were the main cause of runoff declines over the entire basin during the 1990s and in the UZ, MZ and JZ areas during the 2000s, while direct human activities were most important in the DZ and BZ areas during the 2000s.

  10. An integrated framework to assess adaptation options to climate change impacts in an irrigated basin in Central North Chile

    Science.gov (United States)

    Vicuna, S.; Melo, O.; Meza, F. J.; Alvarez, P.; Maureira, F.; Sanchez, A.; Tapia, A.; Cortes, M.; Dale, L. L.

    2013-12-01

    Future climate conditions could potentially affect water supply and demand on water basins throughout the world but especially on snowmelt-driven agriculture oriented basins that can be found throughout central Chile. Increasing temperature and reducing precipitation will affect both the magnitude and timing of water supply this part of the world. Different adaptation strategies could be implemented to reduce the impacts of such scenarios. Some could be incorporated as planned policies decided at the basin or Water Use Organization levels. Examples include changing large scale irrigation infrastructure (reservoirs and main channels) either physically or its operation. Complementing these strategies it is reasonable to think that at a disaggregated level, farmers would also react (adapt) to these new conditions using a mix of options to either modify their patterns of consumption (irrigation efficiency, crop mix, crop area reduction), increase their ability to access new sources of water (groundwater, water markets) or finally compensate their expected losses (insurance). We present a modeling framework developed to represent these issues using as a case study the Limarí basin located in Central Chile. This basin is a renowned example of how the development of reservoirs and irrigation infrastructure can reduce climate vulnerabilities allowing the economic development of a basin. Farmers in this basin tackle climate variability by adopting different strategies that depend first on the reservoir water volume allocation rule, on the type and size of investment they have at their farms and finally their potential access to water markets and other water supplies options. The framework developed can be used to study these strategies under current and future climate scenarios. The cornerstone of the framework is an hydrology and water resources model developed on the WEAP platform. This model is able to reproduce the large scale hydrologic features of the basin such as

  11. A framework for the quantitative assessment of climate change impacts on water-related activities at the basin scale

    Directory of Open Access Journals (Sweden)

    D. Anghileri

    2011-01-01

    Full Text Available While quantitative assessment of the climate change impact on hydrology at the basin scale is quite addressed in the literature, extension of quantitative analysis to impact on the ecological, economic and social sphere is still limited, although well recognized as a key issue to support water resource planning and promote public participation. In this paper we propose a framework for assessing climate change impact on water-related activities at the basin scale. The peculiarities of our approach are that: (i the impact quantification is based on a set of performance indicators defined together with the stakeholders, thus explicitly taking into account the water-users preferences; (ii the management policies are obtained by optimal control techniques, linking stakeholder expectations and decision-making; (iii the multi-objective nature of the management problem is fully preserved by simulating a set of Pareto-optimal management policies, which allows for evaluating not only variations in the indicator values but also tradeoffs among conflicting objectives. The framework is demonstrated by application to a real world case study, Lake Como basin (Italy. We show that the most conflicting water-related activities within the basin (i.e. hydropower production and agriculture are likely to be negatively impacted by climate change. An uncertainty analysis is performed in order to assess how the climate natural variability and approximations in modeling the physical system (climate and hydrology and the socio-economic system (management policy affect the robustness of the estimated impacts. We demonstrate that the contribution of natural climate uncertainty is rather significant and that, among different modelling uncertainty sources, the one from climate modeling is very significant.

  12. A framework for the quantitative assessment of climate change impacts on water-related activities at the basin scale

    Directory of Open Access Journals (Sweden)

    D. Anghileri

    2011-06-01

    Full Text Available While quantitative assessment of the climate change impact on hydrology at the basin scale is quite addressed in the literature, extension of quantitative analysis to impact on the ecological, economic and social sphere is still limited, although well recognized as a key issue to support water resource planning and promote public participation. In this paper we propose a framework for assessing climate change impact on water-related activities at the basin scale. The specific features of our approach are that: (i the impact quantification is based on a set of performance indicators defined together with the stakeholders, thus explicitly taking into account the water-users preferences; (ii the management policies are obtained by optimal control techniques, linking stakeholder expectations and decision-making; (iii the multi-objective nature of the management problem is fully preserved by simulating a set of Pareto-optimal management policies, which allows for evaluating not only variations in the indicator values but also tradeoffs among conflicting objectives. The framework is demonstrated by application to a real world case study, Lake Como basin (Italy. We show that the most conflicting water-related activities within the basin (i.e. hydropower production and agriculture are likely to be negatively impacted by climate change. We discuss the robustness of the estimated impacts to the climate natural variability and the approximations in modeling the physical system and the socio-economic system, and perform an uncertainty analysis of several sources of uncertainty. We demonstrate that the contribution of natural climate uncertainty is rather remarkable and that, among different modelling uncertainty sources, the one from climate modeling is very significant.

  13. Assessing the impact of climate change upon hydrology and agriculture in the Indrawati Basin, Nepal.

    Science.gov (United States)

    Palazzoli, Irene; Bocchiola, Daniele; Nana, Ester; Maskey, Shreedhar; Uhlenbrook, Stefan

    2014-05-01

    Agriculture is sensitive to climate change, especially to temperature and precipitation changes. The purpose of this study was to evaluate the climate change impacts upon rain-fed crops production in the Indrawati river basin, Nepal. The Soil and Water Assessment Tool SWAT model was used to model hydrology and cropping systems in the catchment, and to predict the influence of different climate change scenarios therein. Daily weather data collected from about 13 weather stations during 4 decades were used to constrain the SWAT model, and data from two hydrometric stations used to calibrate/validate it. Then management practices (crop calendar) were applied to specific Hydrological Response Units (HRUs) for the main crops of the region, rice, corn and wheat. Manual calibration of crop production was also carried, against values of crop yield in the area from literature. The calibrated and validated model was further applied to assess the impact of three future climate change scenarios (RCPs) upon the crop productivity in the region. Three climate models (GCMs) were adopted, each with three RCPs (2.5, 4.5, 8.5). Hence, impacts of climate change were assessed considering three time windows, namely a baseline period (1995-2004), the middle of century (2045-2054) and the end of century (2085-2094). For each GCM and RCP future hydrology and yield was compared to baseline scenario. The results displayed slightly modified hydrological cycle, and somewhat small variation in crop production, variable with models and RCPs, and for crop type, the largest being for wheat. Keywords: Climate Change, Nepal, hydrological cycle, crop yield.

  14. Virtual water flows and Water Balance Impacts of the U.S. Great Lakes Basin

    Science.gov (United States)

    Ruddell, B. L.; Mayer, A. S.; Mubako, S. T.

    2014-12-01

    To assess the impacts of human water use and trade on water balances, we estimate virtual water flows for counties in the U.S. portion of the Great Lakes basin. This is a water-rich region, but one where ecohydrological 'hotspots' are created by water scarcity in certain locations (Mubako et al., 2012). Trade shifts water uses from one location to another, causing water scarcity in some locations but mitigating water scarcity in other locations. A database of water withdrawals was assembled to give point-wise withdrawals by location, source, and use category (commercial, thermoelectric power, industrial, agricultural, mining). Point-wise consumptive use is aggregated to the county level, giving direct, virtual water exports by county. A county-level trade database provides import and export data for the various use categories. We link the annual virtual water exported from a county for a given use category to corresponding annual trade exports. Virtual water balances for each county by use category are calculated, and then compared with the renewable annual freshwater supply. Preliminary findings are that overall virtual water balances (imports - exports) are positive for almost all counties, because urban areas import goods and services that are more water intensive than the exported goods and services. However, for some agriculturally-intensive counties, the overall impact of virtual water trade on the water balance is close to zero, and the balance for agricultural sector virtual water trade is negative, reflecting a net impact of economic trade on the water balance in these locations. We also compare the virtual water balance to available water resources, using annual precipitation less evapotranspiration as a crude estimate of net renewable water availability. In some counties virtual water exports approach 30% of the available water resources, indicating the potential for water scarcity, especially from an aquatic ecosystem standpoint.

  15. From ENSEMBLES to CORDEX: exploring the progress for hydrological impact research for the upper Danube basin

    Science.gov (United States)

    Stanzel, Philipp; Kling, Harald

    2017-04-01

    EURO-CORDEX Regional Climate Model (RCM) data are available as result of the latest initiative of the climate modelling community to provide ever improved simulations of past and future climate in Europe. The spatial resolution of the climate models increased from 25 x 25 km in the previous coordinated initiative, ENSEMBLES, to 12 x 12 km in the CORDEX EUR-11 simulations. This higher spatial resolution might yield improved representation of the historic climate, especially in complex mountainous terrain, improving applicability in impact studies. CORDEX scenario simulations are based on Representative Concentration Pathways, while ENSEMBLES applied the SRES greenhouse gas emission scenarios. The new emission scenarios might lead to different projections of future climate. In this contribution we explore these two dimensions of development from ENSEMBLES to CORDEX - representation of the past and projections for the future - in the context of a hydrological climate change impact study for the Danube River. We replicated previous hydrological simulations that used ENSEMBLES data of 21 RCM simulations under SRES A1B emission scenario as meteorological input data (Kling et al. 2012), and now applied CORDEX EUR-11 data of 16 RCM simulations under RCP4.5 and RCP8.5 emission scenarios. The climate variables precipitation and temperature were used to drive a monthly hydrological model of the upper Danube basin upstream of Vienna (100,000 km2). RCM data was bias corrected and downscaled to the scale of hydrological model units. Results with CORDEX data were compared with results with ENSEMBLES data, analysing both the driving meteorological input and the resulting discharge projections. Results with CORDEX data show no general improvement in the accuracy of representing historic climatic features, despite the increase in spatial model resolution. The tendency of ENSEMBLES scenario projections of increasing precipitation in winter and decreasing precipitation in summer is

  16. Traveling Weather Disturbances in Mars' Southern Extratropics: Sway of the Great Impact Basins

    Science.gov (United States)

    Hollingsworth, Jeffery L.

    2016-04-01

    ' transient barotropic/baroclinic eddies are significantly influenced by the great impact basins of this hemisphere (e.g., Argyre and Hellas). In addition, the occurrence of a southern storm zone in late winter and early spring is keyed particularly to the western hemisphere via orographic influences arising from the Tharsis highlands, and the Argyre and Hellas impact basins. Geographically localized transient-wave activity diagnostics are constructed that illuminate fundamental differences amongst such simulations and these are described.

  17. Evaluation of Flood Forecast and Warning in Elbe river basin - Impact of Forecaster's Strategy

    Science.gov (United States)

    Danhelka, Jan; Vlasak, Tomas

    2010-05-01

    Czech Hydrometeorological Institute (CHMI) is responsible for flood forecasting and warning in the Czech Republic. To meet that issue CHMI operates hydrological forecasting systems and publish flow forecast in selected profiles. Flood forecast and warning is an output of system that links observation (flow and atmosphere), data processing, weather forecast (especially NWP's QPF), hydrological modeling and modeled outputs evaluation and interpretation by forecaster. Forecast users are interested in final output without separating uncertainties of separate steps of described process. Therefore an evaluation of final operational forecasts was done for profiles within Elbe river basin produced by AquaLog forecasting system during period 2002 to 2008. Effects of uncertainties of observation, data processing and especially meteorological forecasts were not accounted separately. Forecast of flood levels exceedance (peak over the threshold) during forecasting period was the main criterion as flow increase forecast is of the highest importance. Other evaluation criteria included peak flow and volume difference. In addition Nash-Sutcliffe was computed separately for each time step (1 to 48 h) of forecasting period to identify its change with the lead time. Textual flood warnings are issued for administrative regions to initiate flood protection actions in danger of flood. Flood warning hit rate was evaluated at regions level and national level. Evaluation found significant differences of model forecast skill between forecasting profiles, particularly less skill was evaluated at small headwater basins due to domination of QPF uncertainty in these basins. The average hit rate was 0.34 (miss rate = 0.33, false alarm rate = 0.32). However its explored spatial difference is likely to be influenced also by different fit of parameters sets (due to different basin characteristics) and importantly by different impact of human factor. Results suggest that the practice of interactive

  18. Model to assess the impacts of external drivers on the hydrology of the Ganges River Basin

    Science.gov (United States)

    Muthuwatta, L.; Sood, A.; Sharma, B.

    2014-09-01

    Impact of climate change on the hydrology of the Ganges River Basin (GRB) is simulated by using a hydrological model - Soil and Water Assessment Tool (SWAT). Climate data from the GCM, Hadley Centre Coupled Model, version 3 (HadCM3) was downscaled with PRECIS for the GRB under A1B Special Report on Emission Scenarios (SRES) scenarios. The annual average precipitation will increase by 2.2% and 14.1% by 2030 and 2050, respectively, compared to the baseline period (1981-2010). Spatial distribution of the future precipitation shows that in the substantial areas of the middle part of the GRB, the annual precipitation in 2030 and 2050 will be reduced compared to the baseline period. Simulations indicate that in 2050 the total groundwater recharge would increase by 12%, while the increase of evapotranspiration will be about 10% compared to the baseline period. The water yield is also expected to increase in the future (up to 40% by 2050 compared to baseline), especially during the wetter months. The model setup is available for free from IWMI's modelling inventory.

  19. Assessing Climate Impacts on Hydropower Production: The Case of the Toce River Basin

    Directory of Open Access Journals (Sweden)

    Giovanni Ravazzani

    2016-03-01

    Full Text Available The aim of the presented study is to assess the impacts of climate change on hydropower production of the Toce Alpine river basin in Italy. For the meteorological forcing of future scenarios, time series were generated by applying a quantile-based error-correction approach to downscale simulations from two regional climate models to point scale. Beside a general temperature increase, climate models simulate an increase of mean annual precipitation distributed over spring, autumn and winter, and a significant decrease in summer. A model of the hydropower system was driven by discharge time series for future scenarios, simulated with a spatially distributed hydrological model, with the simulation goal of defining the reservoirs management rule that maximizes the economic value of the hydropower production. The assessment of hydropower production for future climate till 2050 respect to current climate (2001–2010 showed an increase of production in autumn, winter and spring, and a reduction in June and July. Significant change in the reservoir management policy is expected due to anticipation of the date when the maximum volume of stored water has to be reached and an increase of the reservoir drawdown during August and September to prepare storage capacity for autumn inflows.

  20. Climate-change impacts on water resources and hydropower potential in the Upper Colorado River Basin

    Directory of Open Access Journals (Sweden)

    M. Kopytkovskiy

    2015-03-01

    New hydrological insights for the region: Precipitation projections from climate models vary up to 16%; flow projections revealed greater differences, up to 50%. The climate models projected increase in temperature at low elevations with extreme seasonality at high elevations, although summer temperatures increased at all elevations. The models projected a 60% decline in precipitation at lower elevations and a 74% increase at high elevations, although precipitation declined during the summer months at all elevations. Using the A2 scenario an overall decrease in annual flow was predicted, attributed to a reduction in precipitation and increasing temperature trends; however, this was not consistent during the winter months, which showed an increase in precipitation at high elevations and a modest temperature increase during the winter and resulted in an increase in stream flow. The responses to climate change on reservoir levels varied basin-wide due to variability in precipitation, evapotranspiration, and stream flow. Simulations indicated that water levels in Blue Mesa Reservoir (the largest reservoir in the UCRB would decline by more than 70% with increasing annual temperatures. Reservoirs with smaller surface areas to the volume ratio were not significantly impacted by evapotranspiration. Our results indicate that hydropower management strategies in the UCRB must adapt to potential climate change, but the required adaptations are dependent on several factors including reservoir size and location.

  1. Impacts of calibration strategies and ensemble methods on ensemble flood forecasting over Lanjiang basin, Southeast China

    Science.gov (United States)

    Liu, Li; Xu, Yue-Ping

    2017-04-01

    Ensemble flood forecasting driven by numerical weather prediction products is becoming more commonly used in operational flood forecasting applications.In this study, a hydrological ensemble flood forecasting system based on Variable Infiltration Capacity (VIC) model and quantitative precipitation forecasts from TIGGE dataset is constructed for Lanjiang Basin, Southeast China. The impacts of calibration strategies and ensemble methods on the performance of the system are then evaluated.The hydrological model is optimized by parallel programmed ɛ-NSGAII multi-objective algorithm and two respectively parameterized models are determined to simulate daily flows and peak flows coupled with a modular approach.The results indicatethat the ɛ-NSGAII algorithm permits more efficient optimization and rational determination on parameter setting.It is demonstrated that the multimodel ensemble streamflow mean have better skills than the best singlemodel ensemble mean (ECMWF) and the multimodel ensembles weighted on members and skill scores outperform other multimodel ensembles. For typical flood event, it is proved that the flood can be predicted 3-4 days in advance, but the flows in rising limb can be captured with only 1-2 days ahead due to the flash feature. With respect to peak flows selected by Peaks Over Threshold approach, the ensemble means from either singlemodel or multimodels are generally underestimated as the extreme values are smoothed out by ensemble process.

  2. Evaluating Impacts of Industrial Transformation on Water Consumption in the Heihe River Basin of Northwest China

    Directory of Open Access Journals (Sweden)

    Feng Wu

    2014-11-01

    Full Text Available Growing water scarcity is one of the central challenges for sustainability in China, given its burgeoning industry and huge population, especially in the arid and semi-arid inland river basin where precipitation is very limited. Industrial transformation is an important engine of economic growth, which is required to be implemented by governments at all levels in China. Economic models have generally been applied to evaluate the effects of economic policy change (e.g., industrial transformation or adjustment of price on the allocation of production factors. The computable general equilibrium (CGE model is an effective tool to reallocate the primary factors across sectors for different industrial transformation scenarios. In this research, we first briefly introduced the principles and structure of the CGE model, which embeds water resources as a primary factor of production. Then we chose Zhangye as an example to evaluate the impacts of industrial transformation on water consumption under three designed scenarios with the water-embedded CGE model. Simulation results showed that there will be considerable water saving benefit from industrial transformation when the output value of secondary industry and tertiary industry increases and the contribution of the planting sector to the total output value decreases. Finally, we put forward a scheme that can improve water utilization efficiency in policy options.

  3. Potassium Map from Chang'E-2 Constraints the Impact of Crisium and Orientale Basin on the Moon

    Science.gov (United States)

    Zhu, Meng-Hua; Chang, Jin; Ma, Tao; Ip, Wing-Huen; Fa, Wenzhe; Wu, Jian; Cai, Mingsheng; Gong, Yizhong; Hu, Yiming; Xu, Aoao; Tang, Zesheng

    2013-04-01

    KREEP materials were thought to be last crystallized at the lunar crust and mantle boundary. Impact cratering and volcanism are mainly responsible for their distributions on the lunar surface. Therefore, observation of global KREEP materials and investigation of distributions in the areas of large basins are of critical importance to understand the geologic history of the Moon. Here we report the new global potassium distribution on the Moon detected by Chang'E-2 Gamma-ray Spectrometer. We found that our new measurements are in general agreement with previous observation. A new finding and an important difference is that relatively higher K abundances in the Mare Crisium and Mare Orientale than their surrounding rims were detected for the first time. In light of our observations in these two areas, we propose that Crisium and Orientale basin-forming impact events may have penetrated to the lower crust and excavate the deeper materials to the lunar surface.

  4. Potassium map from Chang'E-2 constraints the impact of Crisium and Orientale basin on the Moon.

    Science.gov (United States)

    Zhu, Meng-Hua; Chang, Jin; Ma, Tao; Ip, Wing-Huen; Fa, WenZhe; Wu, Jian; Cai, MingSheng; Gong, YiZhong; Hu, YiMing; Xu, AoAo; Tang, ZeSheng

    2013-01-01

    KREEP materials were thought to be last crystallized at the lunar crust and mantle boundary. Impact cratering and volcanism are mainly responsible for their distributions on the lunar surface. Therefore, observation of global KREEP materials and investigation of distributions in the areas of large basins are of critical importance to understand the geologic history of the Moon. Here we report the new global potassium distribution on the Moon detected by Chang'E-2 Gamma-ray Spectrometer. We found that our new measurements are in general agreement with previous observation. A new finding and an important difference is that relatively higher K abundances in the Mare Crisium and Mare Orientale than their surrounding rims were detected for the first time. In light of our observations in these two areas, we propose that Crisium and Orientale basin-forming impact events may have penetrated to the lower crust and excavate the deeper materials to the lunar surface.

  5. Causes of different impact of Major Baltic Inflows on cod reproduction in the Gotland Basin of the Baltic Sea

    Science.gov (United States)

    Karaseva, E. M.; Zezera, A. S.

    2016-09-01

    The impact of the Major Baltic Inflows (MBIs) of 1976, 1993, and 2003 on cod reproduction in the Gotland Basin of the Baltic Sea is considered based on calculations of the eastern Baltic cod egg abundance and offspring survival indices. The reproductive success (1976-1977) was defined by the elevation of the 11 psu isohaline and deepening of the 2 mL/L isooxygene surface, which provided the formation of a water layer suitable for cod spawning at a depth of 90-130 m. Prerequisites of the appearance of the reproductive layer in 1976-1977 were a previously high salinity level and penetrating two successive MBIs in one year. The cause of the weak MBI impact in 1993 was the previous salinity minimum; in 2003 it was rapid oxygen depletion due to an increase in temperature. As a result of their weaker influence, small and fragmented cod spawning biotopes appeared in the Gotland Basin.

  6. Quantifying the impact of land use change on hydrological responses in the Upper Ganga Basin, India

    Science.gov (United States)

    Tsarouchi, Georgia-Marina; Mijic, Ana; Moulds, Simon; Chawla, Ila; Mujumdar, Pradeep; Buytaert, Wouter

    2013-04-01

    Quantifying how changes in land use affect the hydrological response at the river basin scale is a challenge in hydrological science and especially in the tropics where many regions are considered data sparse. Earlier work by the authors developed and used high-resolution, reconstructed land cover maps for northern India, based on satellite imagery and historic land-use maps for the years 1984, 1998 and 2010. Large-scale land use changes and their effects on landscape patterns can impact water supply in a watershed by altering hydrological processes such as evaporation, infiltration, surface runoff, groundwater discharge and stream flow. Three land use scenarios were tested to explore the sensitivity of the catchment's response to land use changes: (a) historic land use of 1984 with integrated evolution to 2010; (b) land use of 2010 remaining stable; and (c) hypothetical future projection of land use for 2030. The future scenario was produced with Markov chain analysis and generation of transition probability matrices, indicating transition potentials from one land use class to another. The study used socio-economic (population density), geographic (distances to roads and rivers, and location of protected areas) and biophysical drivers (suitability of soil for agricultural production, slope, aspect, and elevation). The distributed version of the land surface model JULES was integrated at a resolution of 0.01° for the years 1984 to 2030. Based on a sensitivity analysis, the most sensitive parameters were identified. Then, the model was calibrated against measured daily stream flow data. The impact of land use changes was investigated by calculating annual variations in hydrological components, differences in annual stream flow and surface runoff during the simulation period. The land use changes correspond to significant differences on the long-term hydrologic fluxes for each scenario. Once analysed from a future water resources perspective, the results will be

  7. Modelling the impacts of sea level rise on tidal basin ecomorphodynamics and mangrove habitat evolution

    Science.gov (United States)

    van Maanen, Barend; Coco, Giovanni; Bryan, Karin

    2016-04-01

    The evolution of tidal basins and estuaries in tropical and subtropical regions is often influenced by the presence of mangrove forests. These forests are amongst the most productive environments in the world and provide important ecosystem services. However, these intertidal habitats are also extremely vulnerable and are threatened by climate change impacts such as sea level rise. It is therefore of key importance to improve our understanding of how tidal systems occupied by mangrove vegetation respond to rising water levels. An ecomorphodynamic model was developed that simulates morphological change and mangrove forest evolution as a result of mutual feedbacks between physical and biological processes. The model accounts for the effects of mangrove trees on tidal flow patterns and sediment dynamics. Mangrove growth is in turn controlled by hydrodynamic conditions. Under stable water levels, model results indicate that mangrove trees enhance the initiation and branching of tidal channels, partly because the extra flow resistance in mangrove forests favours flow concentration, and thus sediment erosion in between vegetated areas. The landward expansion of the channels, on the other hand, is reduced. Model simulations including sea level rise suggest that mangroves can potentially enhance the ability of the soil surface to maintain an elevation within the upper portion of the intertidal zone. While the sea level is rising, mangroves are migrating landward and the channel network tends to expand landward too. The presence of mangrove trees, however, was found to hinder both the branching and headward erosion of the landward expanding channels. Simulations are performed according to different sea level rise scenarios and with different tidal range conditions to assess which tidal environments are most vulnerable. Changes in the properties of the tidal channel networks are being examined as well. Overall, model results highlight the role of mangroves in driving the

  8. VIC distributed hydrological model to predict climate change impact in the Hanjiang Basin

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The climate impact studies in hydrology often rely on climate change information at fine spatial resolution. However, the general circulation model (GCM), which is widely used to simulate future climate scenario, operates on a coarse scale and does not provide reliable data on local or regional scale for hydrological modeling. Therefore the outputs from GCM have to be downscaled to obtain the information fit for hydrologic studies. The variable infiltration capacity (VIC) distributed hydrological model with 9×9 km2 grid resolution was applied and calibrated in the Hanjiang Basin. Validation results show that SSVM can approximate observed precipitation and temperature data reasonably well, and that the VIC model can simulate runoff hydrograph with high model efficiency and low relative error. By applying the SSVM model, the trends of precipitation and temperature (including daily mean temperature, daily maximum temperature and daily minimum temperature) projected from CGCM2 under A2 and B2 scenarios will decrease in the 2020s (2011―2040), and increase in the 2080s (2071―2100). However, in the 2050s (2041―2070), the precipitation will be decreased under A2 scenario and no significant changes under B2 scenario, but the temperature will be not obviously changed under both climate change scenarios. Under both climate change scenarios, the impact analysis of runoff, made with the downscaled precipitation and temperature time series as input of the VIC distributed model, has resulted in a decreasing trend for the 2020s and 2050s, and an overall increasing trend for the 2080s.

  9. VIC distributed hydrological model to predict climate change impact in the Hanjiang Basin

    Institute of Scientific and Technical Information of China (English)

    GUO ShengLian; GUO Jing; ZHANG Jun; CHEN Hua

    2009-01-01

    The climate Impact studies In hydrology often rely on climate change information at fine spatial resolu-tion.However, the general circulation model (GCM), which is widely used to simulate future climate scenario, operates on a coarse scale and does not provide reliable data on local or regional scale for hydrological modeling.Therefore the outputs from GCM have to be downscaled to obtain the informa-tion fit for hydrologic studies.The variable infiltration capacity (VIC) distributed hydrological model with 9×9 km~2 grid resolution was applied and calibrated in the Hanjiang Basin.Validation results show that SSVM can approximate observed precipitation and temperature data reasonably well, and that the VIC model can simulate runoff hydrograph with high model efficiency and low relative error.By apply-Ing the SSVM model, the trends of precipitation and temperature (including daily mean temperature, daily maximum temperature and daily minimum temperature) projected from CGCM2 under A2 and B2 scenarios will decrease in the 2020s (2011-2040), and Increase in the 2080s (2071-2100).However, in the 2050s (2041-2070), the precipitation will be decreased under A2 scenario and no significant changes under B2 scenario, but the temperature will be not obviously changed under both climate change scenarios.Under both climate change scenarios, the impact analysis of runoff, made with the downscaled precipitation and temperature time series as input of the VIC distributed model, has re-sulted in a decreasing trend for the 2020s and 2050s, and an overall increasing trend for the 2080s.

  10. Geochemical hunting of lithogenic and anthropogenic impacts on polymetallic distribution (Bregalnica river basin, Republic of Macedonia).

    Science.gov (United States)

    Balabanova, Biljana; Stafilov, Trajče; Šajn, Robert; Tănăselia, Claudiu

    2016-11-09

    The main subject of this investigation was the assessment of the lithogenic and anthropogenic distribution of 69 elements in the sediments and fluvisol in the Bregalnica river basin. Alluvial soil and fluvisol samples were collected from the total of eighteen locations along the course of the Bregalnica river and additional thirteen samples were collected from its tributaries. The matrix elements accumulation patterns followed the order: Fe > Na > Al > Ca > Mg > K > Ti > P. The potentially toxic elements, such as As, Cd, Pb, and Zn, have enriched content in the sediments in the medium course of the river, where the main anthropogenic introduction activities occurred. By multivariate analysis the dominant geochemical associations were extracted, as follows: F1: Y-Eu-Lu-Cr-V-La-Gd-Nb-Co-Hf-Zr-Ga-Mg-Fe-Sr-Ta-Sn-Li-Na-Rb-Ni-Ge-Be-Cs; F2: As-W-Ba-Ag-Cu-Tl-Zn-Sb-Mo-In-Cd-Te-Bi-Pb and F3: I-Sc-Br-K. Lead and zinc contents were strongly correlated with the hydrothermal exploitations, especially in the area of Neogene clastite and vulcanite. These elements occur as dominant geochemical markers of the anthropogenic impacts of polymetallic enrichments due to the hydrothermal ore exploitation (Factor 2). The impact of Oligocene volcanism (Kratovo-Zletovo region) was observed in the lithological enrichments of Pb, Zn, Cu, As, Sb, Mo and Bi. Despite the natural distribution along the course of the Bregalnica river, an exceptional anomaly in the iron distribution of the old polymetallic unused mineralization was detected in Zone 1 (Berovo region).

  11. Climate impact assessment on water resources and glacierization in the Naryn, Karadarya and Zerafshan basins, Central Asia

    OpenAIRE

    Abror Gafurov; D. Duethmann; D. Kriegel; Katy Unger-Shayesteh; Matthias Huss; D. Farinotti; S. Vorogushyn

    2017-01-01

    Central Asian river basins with their runoff formation zones in high mountains are currently experiencing the impact of increasing temperatures and changes in precipitation. The headwaters thus exhibit negative glacier mass balances, decreasing glacierization, changes in snow cover characteristics and changing runoff response. These changes are likely to intensify in future, as temperatures are projected to grow further. Both hydropower industry and irrigated agriculture in the do...

  12. Win-wins in NTFP market chains? How governance impacts the sustainability of livelihoods based on Congo Basin forest products

    OpenAIRE

    Ingram, V.J.

    2012-01-01

    Exploring the interrelationships between governance, poverty alleviation and sustainability impacts in the framework of market chains for non-timber forest products originating from the Congo Basin. The research focuses on how governance arrangements help or hinder access to forest resources and their exploitation, and the implications for poverty alleviation and sustainable livelihoods. The value chains of nine NTFPs are investigated: (Apiculture products: honey, wax and propolis), pygeum ( ...

  13. Climate change impacts on groundwater resources: modelled deficits in a chalky aquifer, Geer basin, Belgium

    Science.gov (United States)

    Brouyère, Serge; Carabin, Guy; Dassargues, Alain

    An integrated hydrological model (MOHISE) was developed in order to study the impact of climate change on the hydrological cycle in representative water basins in Belgium. This model considers most hydrological processes in a physically consistent way, more particularly groundwater flows which are modelled using a spatially distributed, finite-element approach. Thanks to this accurate numerical tool, after detailed calibration and validation, quantitative interpretations can be drawn from the groundwater model results. Considering IPCC climate change scenarios, the integrated approach was applied to evaluate the impact of climate change on the water cycle in the Geer basin in Belgium. The groundwater model is described in detail, and results are discussed in terms of climate change impact on the evolution of groundwater levels and groundwater reserves. From the modelling application on the Geer basin, it appears that, on a pluri-annual basis, most tested scenarios predict a decrease in groundwater levels and reserves in relation to variations in climatic conditions. However, for this aquifer, the tested scenarios show no enhancement of the seasonal changes in groundwater levels. Un modèle hydrologique intégré (MOHISE) a été développé afin d'étudier l'impact du changement climatique sur le cycle hydrologique de bassins versants représentatifs de Belgique. Ce modèle prend en compte tous les processus hydrologiques d'une manière physiquement consistante, plus particulièrement les écoulements souterrains qui sont modélisés par une approche spatialement distribuée aux éléments finis. Grâce à cet outil numérique précis, après une calibration et une validation détaillées, des interprétations quantitatives peuvent être réalisées à partir des résultats du modèle de nappe. Considérant des scénarios de changements climatiques de l'IPCC, l'approche intégrée a été appliquée pour évaluer l'impact du changement climatique sur le cycle de l

  14. Impact of climate change and agricultural developments in the Taquari River basin, Brazil

    NARCIS (Netherlands)

    Querner, E.P.; Jonker, R.N.J.; Padovani, C.; Soriano, B.; Galdino, S.

    2005-01-01

    The Pantanal wetland is part of the Upper Paraguay River basin. The major driving force of the wetland system is the annual oscillation between dry and wet seasons. This study focussed on the Taquari basin, a tributary of the Paraguay River, where erosion takes place and parts of the river silt up,

  15. Permafrost and infrastructure in the Usa Basin (Northeast European Russia) : Possible impacts of global warming

    NARCIS (Netherlands)

    Mazhitova, G.; Karstkarel, N.; Oberman, N.; Romanovsky, V.; Kuhry, P.

    2004-01-01

    The relationship between permafrost conditions and the distribution of infrastructure in the Usa Basin, Northeast European Russia, is analyzed. About 75% of the Basin is underlain by permafrost terrain with various degrees of continuity (isolated patches to continuous permafrost). The region has a h

  16. Regional variability in dust-on-snow processes and impacts in the Upper Colorado River Basin

    Science.gov (United States)

    Skiles, S. McKenzie; Painter, Thomas H.; Belnap, Jayne; Holland, Lacey; Reynolds, Richard; Goldstein, Harland; Lin, J.

    2015-01-01

    Dust deposition onto mountain snow cover in the Upper Colorado River Basin frequently occurs in the spring when wind speeds and dust emission peaks on the nearby Colorado Plateau. Dust loading has increased since the intensive settlement in the western USA in the mid 1880s. The effects of dust-on-snow have been well studied at Senator Beck Basin Study Area (SBBSA) in the San Juan Mountains, CO, the first high-altitude area of contact for predominantly southwesterly winds transporting dust from the southern Colorado Plateau. To capture variability in dust transport from the broader Colorado Plateau and dust deposition across a larger area of the Colorado River water sources, an additional study plot was established in 2009 on Grand Mesa, 150 km to the north of SBBSA in west central, CO. Here, we compare the 4-year (2010–2013) dust source, deposition, and radiative forcing records at Grand Mesa Study Plot (GMSP) and Swamp Angel Study Plot (SASP), SBBSA's subalpine study plot. The study plots have similar site elevations/environments and differ mainly in the amount of dust deposited and ensuing impacts. At SASP, end of year dust concentrations ranged from 0.83 mg g−1 to 4.80 mg g−1, and daily mean spring dust radiative forcing ranged from 50–65 W m−2, advancing melt by 24–49 days. At GMSP, which received 1.0 mg g−1 less dust per season on average, spring radiative forcings of 32–50 W m−2 advanced melt by 15–30 days. Remote sensing imagery showed that observed dust events were frequently associated with dust emission from the southern Colorado Plateau. Dust from these sources generally passed south of GMSP, and back trajectory footprints modelled for observed dust events were commonly more westerly and northerly for GMSP relative to SASP. These factors suggest that although the southern Colorado Plateau contains important dust sources, dust contributions from other dust sources contribute to dust loading in this region

  17. URBANIZATION AND ITS IMPACTS ON WATER ENVIRONMENT IN TUMEN RIVER BASIN

    Institute of Scientific and Technical Information of China (English)

    WANGShi-jun; WANGDan; 等

    2002-01-01

    The trans-boundary scope of the Tumen River Basin(TRB) going through China,Russia and DPRK has been defined,and on the basis of this,status of urbanization and its impacts on water environment in recent 20years in TRB have analyzed.Urbanization in TRB can be characterized as:1)There is medium level of overall urbanization in TRB.Certain distance still exists compared with developed countries.And it is lower than the average urbanization level of Russia and higher than that of China.2)There is unbalanced distribution of urbanization development in TRB.Urbanization in China part owns the character of low starting point and high-speed development.In Russia part,charac-ter of urbanization can be described as high starting point and stable development.In DPRK part,urbanization level is low,and motive power lacks.3)Due to large population,in China part there is broader region urbanized,larger radius and higher frequency of human activities,which lead to heavier pressure on environment.Meanwhile,the paper has point-ed that impacts of urbanization on water environment are as follows:1)Urban population growth and industry develop-ment increase the demand for freshwater,and also exacerbate the contradiction between limited water supply and increase-ing freshwater demand.2)Urban infrastructure doesnˊt match with urban productive function especially treatment facili-ties,which results in the pollution of the Tumen River.3)The pollution situation in the Tumen River got peak point in 1995,and presently,such situation has been improved in great scale,due to effective interventions adopted.However,there still exist 2enterprises that are urgent to be harnessed.Moreover,pollution of municipal sewage will become more and more apparent.4)The influence of urbanization on soil is mainly caused by industrial effluent and slag,and pollut-ed water irrigation.Soil and water loss has also been a serious problem caused by urbanization.5)Urbanization results in the decrease of wetlands area

  18. URBANIZATION AND ITS IMPACTS ON WATER ENVIRONMENT IN TUMEN RIVER BASIN

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The trans-boundary scope of the Tumen River Basin (TRB) going through China, Russia and DPRK hasbeen defined, and on the basis of this, status of urbanization and its impacts on water environment in recent 20 years inTRB have been analyzed. Urbanization in TRB can be characterized as: 1) There is medium level of overall urbanizationin TRB. Certain distance still exists compared with developed countries. And it is lower than the average urbanizationlevel of Russia and higher than that of China. 2) There is unbalanced distribution of urbanization development in TRB.Urbanization in China part owns the character of low starting point and high-speed development. In Russia part, character of urbanization can be described as high starting point and stable development. In DPRK part, urbanization level islow, and motive power lacks. 3) Due to large population, in China part there is broader region urbanized, larger radiusand higher frequency of human activities, which lead to heavier pressure on environment. Meanwhile, the paper has pointed that impacts of urbanization on water environment are as follows: 1) Urban population growth and industry developmerit increase the demand for freshwater, and also exacerbate the contradiction between limited water supply and increasing freshwater demand. 2) Urban infrastructure doesn't match with urban productive function especially treatment facilities, which results in the pollution of the Tumen River. 3) The pollution situation in the Tumen River got peak point in1995, and presently, such situation has been improved in great scale, due to effective interventions adopted. However,there still exist 2 enterprises that are urgent to be harnessed. Moreover, pollution of municipal sewage will become moreand more apparent. 4) The influence of urbanization on soil is mainly caused by industrial effluent and slag, and polluted water irrigation. Soil and water loss has also been a serious problem caused by urbanization. 5) Urbanization

  19. The impacts of the summer plateau monsoon over the Tibetan Plateau on the rainfall in the Tarim Basin, China

    Science.gov (United States)

    Zhao, Yong; Huang, Anning; Zhou, Yang; Yang, Qing

    2016-10-01

    The impacts of the summer plateau monsoon (PM) over the Tibetan Plateau on summer rainfall over the Tarim Basin in northwest China are investigated, based on the observed rainfall data at 34 stations and the NCEP/NCAR reanalysis data during 1961 to 2007. Results showed that the PM is well correlated to the summer rainfall over the Tarim Basin. Process analysis shows that strong PM corresponds to an anomalous cyclone over the Tibetan Plateau in the middle troposphere and an anomalous anticyclone in the upper troposphere over northwest part of Tibetan Plateau. They result in cold air moving from high latitudes into Central Asia over the western part of Tibetan Plateau. The concurrences of the cooling in the middle-upper troposphere over Central Asia leads to an anomalous cyclone over Central Asia at 500 hPa and the anomalous descending motions prevailing over the cooling region. Associated with this anomaly, there are enhanced southerly winds and corresponding ascending motion over the Tarim Basin located in the east of the cooling region. These processes lead to more summer rainfall over the Tarim Basin.

  20. Cross-scale intercomparison of climate change impacts simulated by regional and global hydrological models in eleven large river basins

    Energy Technology Data Exchange (ETDEWEB)

    Hattermann, F. F.; Krysanova, V.; Gosling, S. N.; Dankers, R.; Daggupati, P.; Donnelly, C.; Flörke, M.; Huang, S.; Motovilov, Y.; Buda, S.; Yang, T.; Müller, C.; Leng, G.; Tang, Q.; Portmann, F. T.; Hagemann, S.; Gerten, D.; Wada, Y.; Masaki, Y.; Alemayehu, T.; Satoh, Y.; Samaniego, L.

    2017-01-04

    Ideally, the results from models operating at different scales should agree in trend direction and magnitude of impacts under climate change. However, this implies that the sensitivity of impact models designed for either scale to climate variability and change is comparable. In this study, we compare hydrological changes simulated by 9 global and 9 regional hydrological models (HM) for 11 large river basins in all continents under reference and scenario conditions. The foci are on model validation runs, sensitivity of annual discharge to climate variability in the reference period, and sensitivity of the long-term average monthly seasonal dynamics to climate change. One major result is that the global models, mostly not calibrated against observations, often show a considerable bias in mean monthly discharge, whereas regional models show a much better reproduction of reference conditions. However, the sensitivity of two HM ensembles to climate variability is in general similar. The simulated climate change impacts in terms of long-term average monthly dynamics evaluated for HM ensemble medians and spreads show that the medians are to a certain extent comparable in some cases with distinct differences in others, and the spreads related to global models are mostly notably larger. Summarizing, this implies that global HMs are useful tools when looking at large-scale impacts of climate change and variability, but whenever impacts for a specific river basin or region are of interest, e.g. for complex water management applications, the regional-scale models validated against observed discharge should be used.

  1. Typical synoptic situations and their impacts on the wintertime air pollution in the Guanzhong basin, China

    Science.gov (United States)

    Bei, Naifang; Li, Guohui; Huang, Ru-Jin; Cao, Junji; Meng, Ning; Feng, Tian; Liu, Suixin; Zhang, Ting; Zhang, Qiang; Molina, Luisa T.

    2016-06-01

    Rapid industrialization and urbanization have caused severe air pollution in the Guanzhong basin, northwestern China, with heavy haze events occurring frequently in recent winters. Using the NCEP reanalysis data, the large-scale synoptic situations influencing the Guanzhong basin during wintertime of 2013 are categorized into six types to evaluate the contribution of synoptic situations to the air pollution, including "north-low", "southwest-trough", "southeast-high", "transition", "southeast-trough", and "inland-high". The FLEXPART model has been utilized to demonstrate the corresponding pollutant transport patterns for the typical synoptic situations in the basin. Except for "southwest-trough" and "southeast-high" (defined as favorable synoptic situations), the other four synoptic conditions (defined as unfavorable synoptic situations) generally facilitate the accumulation of air pollutants, causing heavy air pollution in the basin. In association with the measurement of PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) in the basin, the unfavorable synoptic situations correspond to high PM2.5 mass concentrations or poor air quality and vice versa. The same analysis has also been applied to winters of 2008-2012, which shows that the basin was mainly influenced by the unfavorable synoptic situations during wintertime leading to poor air quality. The WRF-CHEM model has further been applied to simulate the selected 6 days representing the typical synoptic situations during the wintertime of 2013, and the results generally show a good agreement between the modeled distributions and variations of PM2.5 and the corresponding synoptic situations, demonstrating reasonable classification for the synoptic situations in the basin. Detailed meteorological conditions, such as temperature inversion, low-level horizontal wind speed, and planetary boundary layer, all contribute to heavy air pollution events in the basin under unfavorable synoptic conditions

  2. Impacts of Land Use on Surface Water Quality in a Subtropical River Basin: A Case Study of the Dongjiang River Basin, Southeastern China

    Directory of Open Access Journals (Sweden)

    Jiao Ding

    2015-08-01

    Full Text Available Understanding the relationship between land use and surface water quality is necessary for effective water management. We estimated the impacts of catchment-wide land use on water quality during the dry and rainy seasons in the Dongjiang River basin, using remote sensing, geographic information systems and multivariate statistical techniques. The results showed that the 83 sites can be divided into three groups representing different land use types: forest, agriculture and urban. Water quality parameters exhibited significant variations between the urban-dominated and forest-dominated sites. The proportion of forested land was positively associated with dissolved oxygen concentration but negatively associated with water temperature, electrical conductivity, permanganate index, total phosphorus, total nitrogen, ammonia nitrogen, nitrate nitrogen and chlorophyll-a. The proportion of urban land was strongly positively associated with total nitrogen and ammonia nitrogen concentrations. Forested and urban land use had stronger impacts on water quality in the dry season than in the rainy season. However, agricultural land use did not have a significant impact on water quality. Our study indicates that urban land use was the key factor affecting water quality change, and limiting point-source waste discharge in urban areas during the dry season would be critical for improving water quality in the study area.

  3. Inter-Basin Water Transfer Impact Assessment on Environment of Pennar to Cauvery Link Canal

    Science.gov (United States)

    Rajesh, S. V. J. S. S.; Prakasa Rao, B. S.; Niranjan, K.

    2016-07-01

    Owing to its striking differences in its climatic conditions, India is frequently facing with extremities such as heavy rain fall in some regions where as some other regions endure little rainfall. The regions receiving heavy precipitation are facing floods resulting in huge amount of water runs into the sea. Contrarily, the regions, without adequate rainfall are suffering from persistent droughts. To overcome such disparities in the distribution of water, National Water Development Agency (NWDA) put a proposal to transfer water through link canals between rivers. The current study is limited to two river basins, Pennar and Cauvery. The present study is confined to Pennar (somasila) to Cauvery (Grand Anicut) whose length is 483 km. The study consist of10 km. buffer on either side of the canal and it occupies 17,215.68 sq. km. out of these 10,105.96 sq.km.is proposed command area which falls in Chittoor, Chengalpattu, North Arcott and South Arcott districts. Using IRS-P6, LISS-III data the characteristics of the rocks, lineaments, drainage, settlements and land use/land cover are mapped for better analysis and the environmental impact. The study indicated that Current fallow land of 5340.14 km2 and 6307.98 km2 of cropland will be brought under cultivation which is more than what is NWDA estimated land that will be benefited. The canal will provide water for irrigation and drinking to 4597 villages and 244 villages to be rehabilitated. 119 culverts/canal bridges and 24 aqueducts have to be constructed across the canal.

  4. Curonian Lagoon drainage basin modelling and assessment of climate change impact

    Directory of Open Access Journals (Sweden)

    Natalja Čerkasova

    2016-04-01

    Full Text Available The Curonian Lagoon, which is the largest European coastal lagoon with a surface area of 1578 km2 and a drainage area of 100,458 km2, is facing a severe eutrophication problem. With its increasing water management difficulties, the need for a sophisticated hydrological model of the Curonian Lagoon's drainage area arose, in order to assess possible changes resulting from local and global processes. In this study, we developed and calibrated a sophisticated hydrological model with the required accuracy, as an initial step for the future development of a modelling framework that aims to correctly predict the movement of pesticides, sediments or nutrients, and to evaluate water-management practices. The Soil and Water Assessment Tool was used to implement a model of the study area and to assess the impact of climate-change scenarios on the run-off of the Nemunas River and the Minija River, which are located in the Curonian Lagoons drainage basin. The models calibration and validation were performed using monthly streamflow data, and evaluated using the coefficient of determination (R2 and the Nash-Sutcliffe model efficiency coefficient (NSE. The calculated values of the R2 and NSE for the Nemunas and Minija Rivers stations were 0.81 and 0.79 for the calibration, and 0.679 and 0.602 for the validation period. Two potential climate-change scenarios were developed within the general patterns of near-term climate projections, as defined by the Intergovernmental Panel on Climate Change Fifth Assessment Report: both pessimistic (substantial changes in precipitation and temperature and optimistic (insubstantial changes in precipitation and temperature. Both simulations produce similar general patterns in river-discharge change: a strong increase (up to 22% in the winter months, especially in February, a decrease during the spring (up to 10% and summer (up to 18%, and a slight increase during the autumn (up to 10%.

  5. Land Use/Land Cover Change Induced Impacts on Water Supply Service in the Upper Reach of Heihe River Basin

    Directory of Open Access Journals (Sweden)

    Xiaoli Geng

    2014-12-01

    Full Text Available Heihe River Basin is the second largest inland river basin in China, where water supply service in the upper reach has greater influence on the sustainable development of middle and lower reaches. This study analyzed the influence of land use/land cover change (LUCC on the water supply service in the upper reach by carrying out scenario simulation. Firstly, we analyzed the LUCC and climate change in the upper reach during 1990–2005; then the water supply service, which was represented by the annual water yield, was estimated with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST model. Thereafter three scenarios (precipitation change and LUCC change combined, LUCC change only, and precipitation change only were established to analyze the impacts of LUCC and precipitation change on the water yield. The results show that the LUCC exerted great influence on water yield, while the impact of precipitation change is even more significant than that of LUCC. Although there are still some uncertainties, the results of this study can still provide valuable reference information for ecological conservation and water resource management in the upper reach of the Heihe River Basin.

  6. Quantifying the magnitude of the impact of climate change and human activity on runoff decline in Mian River Basin, China.

    Science.gov (United States)

    Fan, Jing; Tian, Fei; Yang, Yonghui; Han, Shumin; Qiu, Guoyu

    2010-01-01

    Runoff in North China has been dramatically declining in recent decades. Although climate change and human activity have been recognized as the primary driving factors, the magnitude of impact of each of the above factors on runoff decline is still not entirely clear. In this study, Mian River Basin (a watershed that is heavily influenced by human activity) was used as a proxy to quantify the contributions of human and climate to runoff decline in North China. SWAT (Soil and Water Assessment Tool) model was used to isolate the possible impacts of man and climate. SWAT simulations suggest that while climate change accounts for only 23.89% of total decline in mean annual runoff, human activity accounts for the larger 76.11% in the basin. The gap between the simulated and measured runoff has been widening since 1978, which can only be explained in terms of increasing human activity in the region. Furthermore, comparisons of similar annual precipitation in 3 dry-years and 3 wet-years representing hydrological processes in the 1970s, 1980s, and 1990s were used to isolate the magnitude of runoff decline under similar annual precipitations. The results clearly show that human activity, rather than climate, is the main driving factor of runoff decline in the basin.

  7. [Draft] Environmental Impact Statement : San Luis Valley Project : Colorado Closed Basin Division

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Closed Basin Division, San Luis Valley Project, Alamosa and Saguache Counties, Colorado, is a multi-purpose water resource plan designated to salvage and deliver...

  8. Climate impact assessment on water resources and glacierization in the Naryn, Karadarya and Zerafshan basins, Central Asia

    Science.gov (United States)

    Gafurov, Abror; Duethmann, Doris; Kriegel, David; Unger-Shayesteh, Katy; Huss, Matthias; Farinotti, Daniel; Vorogushyn, Sergiy

    2017-04-01

    Central Asian river basins with their runoff formation zones in high mountains are currently experiencing the impact of increasing temperatures and changes in precipitation. The headwaters thus exhibit negative glacier mass balances, decreasing glacierization, changes in snow cover characteristics and changing runoff response. These changes are likely to intensify in future, as temperatures are projected to grow further. Both hydropower industry and irrigated agriculture in the downstream areas strongly depend on the water availability, its seasonal and long-term distribution. In order to improve water management policy in the region, reliable assessments of water availability in the runoff formation zones of Central Asia are necessary. One of the approaches to assessment of water resources is the evaluation of climate scenarios using hydrological models. We present an assessment of climate impact on water resources and glacierization in the 21st century using the semi-distributed hydrological model WASA in the Naryn, Karadarya and Zerafshan basins in Central Asia. In order to constrain hydrological model parameters reliably, a multi-objective calibration approach using observed discharge, glacier mass balance and satellite snow cover data was applied. Consideration of initial glacier volume and its temporal dynamics can be essential for climate impact assessment in transient model simulations. Here, we used estimates of initial glacier thickness, calculated glacier mass balance, and the ∆h-approach to simulate the glacier evolution on an annual basis. Future climate scenarios based on the CMIP5 ensemble projections reflecting cold-wet, cold-dry, warm-wet, and warm-dry conditions were used and bias corrected with an empirical quantile mapping technique. The results indicate that the impact of changing climate varies regionally. Based on the ensemble mean of the simulated glacier area evolution, the glacier area retreat is fastest in the low-lying Karadarya basin

  9. Impact of climate evolution and land use changes on water yield in the Ebro basin

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    J. I. López-Moreno

    2010-04-01

    Full Text Available In this study the climatic and hydrological trends across 88 sub-basins of the Ebro River basin were analyzed for the period 1950–2006. A new database of climate information and river flows for the entire basin facilitated a spatially distributed assessment of climate-runoff relationships. It constitutes the first assessment of water yield evolution across the whole Ebro basin, a very representative example of large Mediterranean rivers. The results revealed a marked decrease in river discharges in most of the sub-basins. Moreover, a number of changes in the seasonality of the river regime was found, resulting from dam regulation and a decrease in snowpack in the headwaters. Significant and positive trends in temperature were observed across most of the basin, whereas most of the precipitation series showed negative coefficients, although the decrease in magnitude was low. The time evolution of the residuals from empirical models that relate climate and runoff in each sub-basin provided evidence that climate alone does not explain the observed decrease in river discharge. Thus, changes in water yield are associated with an increase in evapotranspiration rates in natural vegetation, growth of which has expanded as a consequence of land abandonment in areas where agricultural activities and livestock pressure have decreased. In the lowlands of the basin the decrease in water yield has been exacerbated by increased water consumption for domestic, industrial and agricultural uses. Climate projections for the end of the 21st century suggest a reduced capacity for runoff generation because of increasing temperature and less precipitation. Thus, the maintenance of water supply under conditions of increasing demand presents a challenging issue requiring appropriate coordination amongst politicians and managers.

  10. Impact of climate evolution and land use changes on water yield in the ebro basin

    Directory of Open Access Journals (Sweden)

    J. I. López-Moreno

    2011-01-01

    Full Text Available In this study the climatic and hydrological trends across 88 sub-basins of the Ebro River basin were analyzed for the period 1950–2006. A new database of climate information and river flows for the entire basin facilitated a spatially distributed assessment of climate-runoff relationships. It constitutes the first assessment of water yield evolution across the whole Ebro basin, a very representative example of large Mediterranean rivers. The results revealed a marked decrease in river discharges in most of the sub-basins. Moreover, a number of changes in the seasonality of the river regime was found, resulting from dam regulation and a decrease in snowpack in the headwaters. Significant and positive trends in temperature were observed across most of the basin, whereas most of the precipitation series showed negative coefficients, although the decrease in magnitude was low. The time evolution of the residuals from empirical models that relate climate and runoff in each sub-basin provided evidence that climate alone does not explain the observed decrease in river discharge. Thus, changes in water yield are associated with an increase in evapotranspiration rates in natural vegetation, growth of which has expanded as a consequence of land abandonment in areas where agricultural activities and livestock pressure have decreased. In the lowlands of the basin the decrease in water yield has been exacerbated by increased water consumption for domestic, industrial and agricultural uses. Climate projections for the end of the 21st century suggest a reduced capacity for runoff generation because of increasing temperature and less precipitation. Thus, the maintenance of water supply under conditions of increasing demand presents a challenging issue requiring appropriate coordination amongst politicians and managers.

  11. Impact of Cenozoic strike-slip tectonics on the evolution of the northern Levant Basin (offshore Lebanon)

    Science.gov (United States)

    Ghalayini, Ramadan; Daniel, Jean-Marc; Homberg, Catherine; Nader, Fadi H.; Comstock, John E.

    2014-11-01

    Sedimentary basins adjacent to plate boundaries contain key tectonic and stratigraphic elements to understand how stress is transmitted through plates. The Levant Basin is a place of choice to study such elements because it flanks the Levant Fracture System and the Africa/Anatolia boundary. This paper uses new high-quality 3-D seismic reflection data to unravel the tectonic evolution of the margin of this basin during the Cenozoic, the period corresponding to the formation of the Levant Fracture System, part of the Africa/Arabia plate boundary. Four major groups of structures are identified in the interpreted Cenozoic units: NW-SE striking normal faults, NNE-SSW striking thrust-faults, ENE-WSW striking dextral strike-slip faults, and NNE trending anticlines. We demonstrate that all structures, apart of the NW-SE striking normal faults, are inherited from Mesozoic faults. Their reactivation and associated folding started during the late Miocene prior to the Messinian salinity crisis due to a NW-SE compressional stress field. No clear evidence of shortening at present-day offshore Lebanon and no large NNE-SSW strike-slip faults parallel to the restraining bend are found indicating that the Levant Fracture System is mainly contained onshore at present day. The intermittent activity of the interpreted structures correlates with the two stages of Levant Fracture System movement during late Miocene and Pliocene. This paper provides a good example of the impact of the evolution of plate boundaries on adjacent basins and indicates that any changes in the stress field, as controlled by the plate boundary, will affect immediately the preexisting structures in adjacent basins.

  12. The Impact of Climate Change on the Duration and Division of Flood Season in the Fenhe River Basin, China

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    Hejia Wang

    2016-03-01

    Full Text Available This study analyzes the duration and division of the flood season in the Fenhe River Basin over the period of 1957–2014 based on daily precipitation data collected from 14 meteorological stations. The Mann–Kendall detection, the multiscale moving t-test, and the Fisher optimal partition methods are used to evaluate the impact of climate change on flood season duration and division. The results show that the duration of the flood season has extended in 1975–2014 compared to that in 1957–1974. Specifically, the onset date of the flood season has advanced 15 days, whereas the retreat date of the flood season remains almost the same. The flood season of the Fenhe River Basin can be divided into three stages, and the variations in the onset and retreat dates of each stage are also examined. Corresponding measures are also proposed to better utilize the flood resources to adapt to the flood season variations.

  13. Identifying stakeholder-relevant climate change impacts: a case study in the Yakima River Basin, Washington, USA

    Science.gov (United States)

    Jenni, K.; Graves, D.; Hardiman, Jill M.; Hatten, James R.; Mastin, Mark C.; Mesa, Matthew G.; Montag, J.; Nieman, Timothy; Voss, Frank D.; Maule, Alec G.

    2014-01-01

    Designing climate-related research so that study results will be useful to natural resource managers is a unique challenge. While decision makers increasingly recognize the need to consider climate change in their resource management plans, and climate scientists recognize the importance of providing locally-relevant climate data and projections, there often remains a gap between management needs and the information that is available or is being collected. We used decision analysis concepts to bring decision-maker and stakeholder perspectives into the applied research planning process. In 2009 we initiated a series of studies on the impacts of climate change in the Yakima River Basin (YRB) with a four-day stakeholder workshop, bringing together managers, stakeholders, and scientists to develop an integrated conceptual model of climate change and climate change impacts in the YRB. The conceptual model development highlighted areas of uncertainty that limit the understanding of the potential impacts of climate change and decision alternatives by those who will be most directly affected by those changes, and pointed to areas where additional study and engagement of stakeholders would be beneficial. The workshop and resulting conceptual model highlighted the importance of numerous different outcomes to stakeholders in the basin, including social and economic outcomes that go beyond the physical and biological outcomes typically reported in climate impacts studies. Subsequent studies addressed several of those areas of uncertainty, including changes in water temperatures, habitat quality, and bioenergetics of salmonid populations.

  14. Impacts of climate on shrubland fuels and fire behavior in the Owyhee Basin, Idaho

    Science.gov (United States)

    Vogelmann, J. E.; Shi, H.; Hawbaker, T.; Li, Z.

    2013-12-01

    There is evidence that wildland fire is increasing as a function of global change. However, fire activity is spatially, temporally and ecologically variable across the globe, and our understanding of fire risk and behavior in many ecosystems is limited. After a series of severe fire seasons that occurred during the late 1990's in the western United States, the LANDFIRE program was developed with the goals of providing the fire community with objective spatial fuel data for assessing wildland fire risk. Even with access to the data provided by LANDFIRE, assessing fire behavior in shrublands in sagebrush-dominated ecosystems of the western United States has proven especially problematic, in part due to the complex nature of the vegetation, the variable influence of understory vegetation including invasive species (e.g. cheatgrass), and prior fire history events. Climate is undoubtedly playing a major role, affecting the intra- and inter-annual variability in vegetation conditions, which in turn impacts fire behavior. In order to further our understanding of climate-vegetation-fire interactions in shrublands, we initiated a study in the Owyhee Basin, which is located in southwestern Idaho and adjacent Nevada. Our goals include: (1) assessing the relationship between climate and vegetation condition, (2) quantifying the range of temporal variability in grassland and shrubland fuel loads, (3) identifying methods to operationally map the variability in fuel loads, and (4) assessing how the variability in fuel loads affect fire spread simulations. To address these goals, we are using a wide variety of geospatial data, including remotely sensed time-series data sets derived from MODIS and Landsat, and climate data from DAYMET and PRISM. Remotely-sensed information is used to characterize climate-induced temporal variability in primary productivity in the Basin, where fire spread can be extensive after senescence when dry vegetation is added to dead fuel loads. Gridded

  15. Simulation of the impacts land use and land cover changes - LUCC on the hydrological response of the Ji-Parana Basin with MGB-INPE model

    Science.gov (United States)

    Rodriguez, D. A.; Tomasella, J.

    2012-04-01

    Hydrological response results from innumerous processes interacting at different spatial and temporal scales and with various intensities. Since the hydrological impacts of Land use and land cover change (LUCC) and climate variability (CV) are strongly dependent on soil water flow pathways, an adequate representation of the runoff generation mechanisms are crucial to assess the hydrological impacts of LUCC and CV on a basin scale. Model responses to LUCC depend on structure and parameterizations used in the model. There are two basic methodologies adopted to define the structure of the hydrological model: downward and upward approaches. Upward approach is more appropriate for identifying causal relationships, but their results are highly affected by assumptions used in the development of the model. Besides, model structure and parameters values definition are strongly affected by scale issues and their inter-relationships. Downward approach is more appropriate for studying the effects of LUCC, but casual relationships are more difficult to identify. MGB-INPE model was developed based on the Large Scale Basins Model of Brazilian Institute of Hydraulic Research (MGB-IPH). It uses the Xinanjiang Model approach for soil water capacity distribution at each cell combined with TopModel philosophy. Both methodologies follow a downward approach: the hydrologic response of the basin is associated with patterns of self-organization observed at the basin-scale. The model was applied in the Ji-Parana Basin (JPB), a 30.000-km2 basin in the SW Amazonia. The JPB is part of the Deforestation Arc of Amazonia in Brazil and it has lost more than 50 % of his forest cover since the 80's. Simulations were performed between 1982 and 2005 considering annual land use and land cover change. MGB-INPE model was able to represent the impact of LUCC in the runoff generation process and its dependence with basin topography. Simulation results agree with observational studies: LUCC impacts in fast

  16. Impact of land-use change on hydrological processes in the Maying River basin, China

    Institute of Scientific and Technical Information of China (English)

    WANG Genxu; ZHANG YU; LIU Guimin; CHEN Lin

    2006-01-01

    Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of China. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest China, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors,i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large areas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 28.12%, a base flow decline of 35.32%, a drop in the maximum peak discharge of 35.77%, and mean discharge decreases in spring and autumn of 36.05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73%-81%,and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

  17. Environmental impact studies for gas hydrate production test in the Ulleung Basin, East Sea of Korea

    Science.gov (United States)

    Ryu, Byong-Jae

    2017-04-01

    To develop potential future energy resources, the Korean National Gas Hydrate Program has been carried out since 2005. The program has been supported by the Ministry of Trade, Industry and Energy (MOTIE), and carried out by the Korea Institute of Geoscience and Mineral Resources (KIGAM), the Korea Gas Corporation (KOGAS) and the Korea National Oil Corporation (KNOC) under the management of Gas Hydrate R&D Organization (GHDO). As a part of this national program, geophysical surveys, geological studies on gas hydrates and two deep drilling expeditions were performed. Gas hydrate-bearing sand layers suitable for production using current technologies were found during the Second Ulleung Basin Gas Hydrate Drilling Expedition (UBGH2) in 2010. Environmental impact studies (EIS) also have been carried out since 2012 by KIGAM in cooperation with domestic and foreign universities and research organizations to ensure safe production test that will be performed in near future. The schedule of production test is being planned. The EIS includes assessment of environmental risks, examination on domestic environmental laws related with production test, collection of basic oceanographic information, and baseline and monitoring surveys. Oceanographic information and domestic environmental laws are already collected and analyzed. Baseline survey has been performed using the in-house developed system, KIGAM Seafloor Observation System (KISOS) since 2013. It will also be performed. R/V TAMHAE II of KIGAM used for KISOS operation. As a part of this EIS, pseudo-3D Chirp survey also was carried out in 2014 to determine the development of fault near the potential testing site. Using KIGAM Seafloor Monitoring System (KIMOS), monitoring survey is planned to be performed from three month before production test to three months after production test. The geophysical survey for determining the change of gas hydrate reservoirs and production-efficiency around the production well would also be

  18. Pre-monsoon aerosol characteristics over the Indo-Gangetic Basin: implications to climatic impact

    Science.gov (United States)

    Srivastava, A. K.; Tiwari, S.; Devara, P. C. S.; Bisht, D. S.; Srivastava, Manoj K.; Tripathi, S. N.; Goloub, P.; Holben, B. N.

    2011-05-01

    Sun/sky radiometer observations over the Indo-Gangetic Basin (IGB) region during pre-monsoon (from April-June 2009) have been processed to analyze various aerosol characteristics in the central and eastern IGB region, represented by Kanpur and Gandhi College, respectively, and their impacts on climate in terms of radiative forcing. Monthly mean aerosol optical depth (AOD at 500 nm) and corresponding Angstrom Exponent (AE at 440-870 nm, given within the brackets) was observed to be about 0.50 (0.49) and 0.51 (0.65) in April, 0.65 (0.74) and 0.67 (0.91) in May and 0.69 (0.45) and 0.77 (0.71) in June at Kanpur and Gandhi College, respectively. Results show a positive gradient in AOD and AE from central to eastern IGB region with the advancement of the pre-monsoon, which may be caused due to diverse geographical location of the stations having different meteorological conditions and emission sources. Relatively lower SSA was observed at the eastern IGB (0.89) than the central IGB (0.92) region during the period, which suggests relative dominance of absorbing aerosols at the eastern IGB as compared to central IGB region. The absorbing aerosol optical properties over the station suggest that the atmospheric absorption over central IGB region is mainly due to dominance of coarse-mode dust particles; however, absorption over eastern IGB region is mainly due to dominance of fine-particle pollution. The derived properties from sun/sky radiometer during pre-monsoon period are used in a radiative-transfer model to estimate aerosol radiative forcing at the top-of-the atmosphere (TOA) and at the surface over the IGB region. Relatively large TOA and surface cooling was observed at the eastern IGB as compared to the central IGB region. This translates into large heating of the atmosphere ranging from 0.45 to 0.55 K day-1 at Kanpur and from 0.45 to 0.59 K day-1 at Gandhi College.

  19. The impact of land abandonment on species richness and abundance in the Mediterranean Basin: a meta-analysis.

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    Tobias Plieninger

    Full Text Available Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1 which taxonomic groups (arthropods, birds, lichen, vascular plants are more affected by land abandonment; (2 at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3 whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4 how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, P<0.0001 plant and animal species richness and abundance overall, though results were heterogeneous, with differences in effect size between taxa, spatial-temporal scales, land uses, landforms, and climate. In conclusion, there is no "one-size-fits-all" conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity.

  20. The impact of land abandonment on species richness and abundance in the Mediterranean Basin: a meta-analysis.

    Science.gov (United States)

    Plieninger, Tobias; Hui, Cang; Gaertner, Mirijam; Huntsinger, Lynn

    2014-01-01

    Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, Plandforms, and climate. In conclusion, there is no "one-size-fits-all" conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity.

  1. Modeling Climate and Management Change Impacts on Water Quality and In-Stream Processes in the Elbe River Basin

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    Cornelia Hesse

    2016-01-01

    Full Text Available Eco-hydrological water quality modeling for integrated water resources management of river basins should include all necessary landscape and in-stream nutrient processes as well as possible changes in boundary conditions and driving forces for nutrient behavior in watersheds. The study aims to assess possible impacts of the changing climate (ENSEMBLES climate scenarios and/or land use conditions on resulting river water quantity and quality in the large-scale Elbe river basin by applying a semi-distributed watershed model of intermediate complexity (SWIM with implemented in-stream nutrient (N+P turnover and algal growth processes. The calibration and validation results revealed the ability of SWIM to satisfactorily simulate nutrient behavior at the watershed scale. Analysis of 19 climate scenarios for the whole Elbe river basin showed a projected increase in temperature (+3 °C and precipitation (+57 mm on average until the end of the century, causing diverse changes in river discharge (+20%, nutrient loads (NO3-N: −5%; NH4-N: −24%; PO4-P: +5%, phytoplankton biomass (−4% and dissolved oxygen concentration (−5% in the watershed. In addition, some changes in land use and nutrient management were tested in order to reduce nutrient emissions to the river network.

  2. Analysis of spatio-temporal land cover changes for hydrological impact assessment within the Nyando River Basin of Kenya.

    Science.gov (United States)

    Olang, Luke Omondi; Kundu, Peter; Bauer, Thomas; Fürst, Josef

    2011-08-01

    The spatio-temporal changes in the land cover states of the Nyando Basin were investigated for auxiliary hydrological impact assessment. The predominant land cover types whose conversions could influence the hydrological response of the region were selected. Six Landsat images for 1973, 1986, and 2000 were processed to discern the changes based on a methodology that employs a hybrid of supervised and unsupervised classification schemes. The accuracy of the classifications were assessed using reference datasets processed in a GIS with the help of ground-based information obtained through participatory mapping techniques. To assess the possible hydrological effect of the detected changes during storm events, a physically based lumped approach for infiltration loss estimation was employed within five selected sub-basins. The results obtained indicated that forests in the basin declined by 20% while agricultural fields expanded by 16% during the entire period of study. Apparent from the land cover conversion matrices was that the majority of the forest decline was a consequence of agricultural expansion. The model results revealed decreased infiltration amounts by between 6% and 15%. The headwater regions with the vast deforestation were noted to be more vulnerable to the land cover change effects. Despite the haphazard land use patterns and uncertainties related to poor data quality for environmental monitoring and assessment, the study exposed the vast degradation and hence the need for sustainable land use planning for enhanced catchment management purposes.

  3. Climate Change and Its Impacts on Water Resources in the Bandama Basin, Côte D’ivoire

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    Gneneyougo Emile Soro

    2017-03-01

    Full Text Available This study aims to assess future trends in monthly rainfall and temperature and its impacts on surface and groundwater resources in the Bandama basin. The Bandama river is one of the four major rivers of Côte d’Ivoire. Historical data from 14 meteorological and three hydrological stations were used. Simulation results for future climate from HadGEM2-ES model under representative concentration pathway (RCP 4.5 and RCP 8.5 scenarios indicate that the annual temperature may increase from 1.2 °C to 3 °C. These increases will be greater in the north than in the south of the basin. The monthly rainfall may decrease from December to April in the future. During this period, it is projected to decrease by 3% to 42% at all horizons under RCP 4.5 and by 5% to 47% under RCP 8.5. These variations will have cause an increase in surface and groundwater resources during the three periods (2006–2035; 2041–2060; 2066–2085 under the RCP 4.5 scenario. On the other side, these water resources may decrease for all horizons under RCP 8.5 in the Bandama basin.

  4. Impact of climatic and other changes on water resources and demand in river basins: a global analysis

    Science.gov (United States)

    Doell, P.; Floerke, M.; Maerker, M.; Vassolo, S.

    2003-04-01

    To obtain a globally consistent picture of the present and future water resources situation, the water use and availability model WaterGAP 2 was applied to derive global scenarios of water use and availability (and thus water stress). In these scenarios, the impact of climate change on water availability and irrigation water requirements are taken into account, while the impact of demographic, technological and socio-economic changes on water use is considered. In a globalized world, such a scenario analysis can also provide useful information for the sustainable management of individual river basins, in particular considering virtual water transports among river basins in the form of irrigated food or electricity. WaterGAP 2 (spatial resolution 0.5 degree) consists of the global hydrological model WGHM and of water use models for the sectors irrigation, livestock, households and industry. WGHM computes monthly values of surface runoff, groundwater recharge and river discharge in river basins. It is tuned against observed discharge at 724 gauging stations to achieve a good simulation of the long-term average river discharge. Validation efforts have shown than WGHM can satisfactorily simulate the 90 percent reliable monthly discharge Q90 of river basins larger than 20,000 km2, which in addition to the long-term average river discharge is a good indicator for water availability. The water use models compute both water withdrawals and consumptive water uses. The potential climate change impact is computed for two different greenhouse gas emission scenarios of IPCC, A2 and B2, which were each translated into climate scenarios by two state-of-the-art global climate models, ECHAM4 and HadCM3. These emission scenarios are based on storylines that describe alternative possible developments of society until 2100. The B2 scenario assumes a more environmentally oriented society than A2 and results in much lower emissions. Consistent with these storylines and the pertaining

  5. The Socio-Economic Impacts on Water Resources in the Răut River Basin

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    Petru Bacal

    2016-10-01

    Full Text Available The purpose of this research consists in the elucidation of spatial and economic aspects of the water use in the Răut river basin. The main topics presented in this paper are: 1 the dynamics of volume of wastewater discharged into the river Raut basin and its sections; 2 wastewater discharge by the degree of treatment; 3 spatial and branch profile of wastewater discharged: 4 existing problems in evaluation and monitoring of waste water. To achieve these objectives were used traditional methods of geographical and economic research.

  6. The Impact of Land Cover and Land Use Changes on the Hydrological Cycle of the Tarim Basin, NW China

    Science.gov (United States)

    Yang, Y.; Ozdogan, M.; Kurban, A.; Steven, L. I.; Chen, X.

    2015-12-01

    The Tarim Basin, located in NW China, is the largest inland basin in the world. Since 1970s, the basin became modernized agriculturally through unprecedented reclamation which were controlled by the Chinese government to promote cotton production. In 2013, 40% of China's cotton production is harvested in the Tarim Basin, representing 15% of world production. However, these large scale land use transformations lead to overuse of water resources in the upper and middle reaches for irrigation, with severe unintended ecological consequences in the lower reaches. The lower reaches of the Tarim River dried up gradually during the 1970s. In 2000, a water release project was launched to meet the ecological water demands of the river's lower reaches. So far there have been 15 water releases with 1.7 billion USD invested. This work aims to improve our understanding of the impacts on the hydrologic cycle from land-use/land-cover change activities in the Tarim Basin by bridging boundaries between different disciplines and integrating them to portray all the key processes involved. This multidisciplinary approach includes analysis of remotely sensed imagery, application of a dynamic crop modelling framework, and simulation analyses with a transient, 2D, variably-saturated groundwater model. My primary findings show that in 2006, about 25820 km2 were identified as irrigated field. This is a 41% increase from 1970s, when the total irrigated area was only 18250 km2. The rapid expansions in irrigate fields, together with climate change, have affected the partitioning of water between the land surface and the lower atmosphere through changing evapotranspiration patterns. Approximately 7 km3 of water entered the atmosphere through crop evapotranspiration in 1971, but by 2006 this value had increased to nearly 11 km3. But changes in climatic conditions accounted for only 20% of the total increase in ET. In terms of ecological restoration, the study shows the current water releases

  7. Assessment of Impacts of Climate Change on the Water Resources of the Transboundary Jhelum River Basin of Pakistan and India

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    Rashid Mahmood

    2016-06-01

    Full Text Available Pakistan’s economy is significantly reliant on agriculture. However, Pakistan is included in the most water-stressed countries in the world, and its water resources are considerably vulnerable to climate variability and climate change. Therefore, in the present study, the water resources of the Jhelum River basin, which provides water to 6 million hectares of land of Pakistan and hydropower production, were assessed under the scenarios A2 and B2 of HadCM3. A hydrological model, Hydrologic Modeling System (HEC-HMS, was set up, calibrated, and validated for the Jhelum basin, and then streamflow was simulated for three future periods: 2011–2040, 2041–2070, and 2071–2099. The simulated streamflow of each period was compared with the simulated streamflow of the baseline period (1971–2000 to find the changes in the following indicators: mean flow, low flow, median flow, high flow, and center-of-volume dates (CVDs. The results of the study showed an increase of 10%–15% in the mean annual flow as compared to the baseline flow at the end of this century. Winter, spring, and autumn showed an increase in streamflow at most of the sites in all three periods. However, summer (the monsoon season in the basin showed decreased streamflow at most of the sites. Maximum increase at Azad Pattan was projected in winter in the 2080s, with about 37%–39% increase in flow under both scenarios. Low and median flows were projected to increase, but a decline in high flow was detected in the future under both scenarios. It was also concluded that half of the annual flow in the basin will pass by the Azad Pattan site one week earlier than it does now. On the whole, the Jhelum basin would face more temporal and magnitudinal variations in high, low, and mean flows relative to present conditions. This shows that without a consideration of climate change impacts, proper utilization and management of water resources in the basin will be more difficult.

  8. Impact of climate change and anthropogenic activities on stream flow and sediment discharge in the Wei River basin, China

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    P. Gao

    2012-03-01

    Full Text Available Reduced stream flow and increased sediment discharge are a major concern in the Yellow River basin of China which supplies water for agriculture, industry and the growing populations located along the river. Similar concerns exist in the Wei River basin which is the largest tributary of the Yellow River basin and comprises the highly eroded Loess Plateau. Better understanding of the drivers of stream flow and sediment discharge dynamics in the Wei River basin is needed for development of effective management strategies for the region and entire Yellow River basin. In this regard we analysed long term trends for water and sediment discharge during the flood season in the Wei River basin, China. Stream flow and sediment discharge data for 1932 to 2008 from existing hydrological stations located in two sub-catchments and at two points in the Wei River were analysed. Precipitation data were analysed from corresponding meteorological stations. We identified change points or transition years for the trends by the Pettitt method and, using double mass curves, we diagnosed whether they were caused by precipitation changes, human intervention, or both. We found significant decreasing trends for stream flow and sediment discharge during the flood season in both sub-catchments and in the Wei River itself. Change-point analyses further revealed that transition years existed and that rapid decline in stream flow began in 1968 (P<0.01, and that sediment discharge began in 1981 (P<0.01 in the main river. In the two sub-catchments, the transition years were 1985 (P<0.01 and 1994 (P<0.05 for water discharge, and 1978 and 1979 for sediment discharge (P<0.05, respectively. The impact of precipitation or human activity on the reduction amount after the transition years was estimated by double mass curves of precipitation vs stream flow (sediment. For reductions in stream flow and sediment discharge, the contribution rate of human

  9. Impact of climate change and anthropogenic activities on stream flow and sediment discharge in the Wei River basin, China

    Directory of Open Access Journals (Sweden)

    P. Gao

    2013-03-01

    Full Text Available Reduced stream flow and increased sediment discharge are a major concern in the Yellow River basin of China, which supplies water for agriculture, industry and the growing populations located along the river. Similar concerns exist in the Wei River basin, which is the largest tributary of the Yellow River basin and comprises the highly eroded Loess Plateau. Better understanding of the drivers of stream flow and sediment discharge dynamics in the Wei River basin is needed for development of effective management strategies for the region and entire Yellow River basin. In this regard we analysed long-term trends for water and sediment discharge during the flood season in the Wei River basin, China. Stream flow and sediment discharge data for 1932 to 2008 from existing hydrological stations located in two subcatchments and at two points in the Wei River were analysed. Precipitation and air temperature data were analysed from corresponding meteorological stations. We identified change-points or transition years for the trends by the Pettitt method and, using double mass curves, we diagnosed whether they were caused by precipitation changes, human intervention, or both. We found significant decreasing trends for stream flow and sediment discharge during the flood season in both subcatchments and in the Wei River itself. Change-point analyses further revealed that transition years existed and that rapid decline in stream flow began in 1968 (P P P P P < 0.05, respectively. The impact of precipitation or human activity on the reduction amount after the transition years was estimated by double mass curves of precipitation vs. stream flow (sediment. For reductions in stream flow and sediment discharge, the contribution rate of human activity was found to be 82.80 and 95.56%, respectively, and was significantly stronger than the contribution rate of precipitation. This evidence clearly suggests that, in the absence of significant decreases in precipitation

  10. An Application of Advanced Ensemble Streamflow Prediction Methods to Assess Potential Impacts of the 2015 - 2016 ENSO Event over the Colorado River Basin

    Science.gov (United States)

    Miller, W. P.; Lamb, K. W.; Piechota, T. C.; Lakshmi, V.; Santos, N. I.; Tootle, G. A.; Kalra, A.; Fayne, J.

    2015-12-01

    Water resource managers throughout the Western United States have struggled with persistent and severe drought since the early 2000s. In the Colorado River Basin, the National Oceanic and Atmospheric Administration's (NOAA's) Colorado Basin River Forecast Center (CBRFC) provides forecasts of water supply conditions to resource managers throughout the basin using Ensemble Streamflow Prediction (ESP) methods that are largely driven by historical observations of temperature and precipitation. Currently, the CBRFC does not have a way to incorporate information from climatic teleconnections such as the El Niño Southern Oscillation (ENSO). ENSO describes warming sea surface temperatures in the Pacific Ocean that typically correlate with cool and wet winter precipitation events in California and the Lower Colorado River Basin during an El Niño event. Past research indicates the potential to identify analog ENSO events to evaluate the impact to reservoir storage in the Colorado River Basin. Current forecasts indicate the potential for one of the strongest El Niño events on record this winter. In this study, information regarding the upcoming ENSO event is used to inform water supply forecasts over the Upper Colorado River Basin. These forecasts are then compared to traditionally derived water supply forecast in an attempt to evaluate the possible impact of the El Niño event to water supply over the Colorado River Basin.

  11. ASSESSMENT OF THE POTENTIAL IMPACT OF CLIMATE CHANGE UPON SURFACE WATER RESOURCES IN THE PRAHOVA RIVER BASIN

    Directory of Open Access Journals (Sweden)

    M. RETEGAN

    2014-10-01

    Full Text Available The aim of the present research is the determination of the impact of possible climatic changes in the 21st century upon surface water resources in the Prahova river basin using the WatBal model (a mathematical-hydrological water-balance model. The analyzed river basin covers an area of 3682 km² and is located outside the curvature of the Carpathian Mountains, in an area where the altitude varies between 60 m and 2500 m. In accordance with the altitude, the annual precipitation varies from approximately 550 mm/year in the plain area to over 1000 mm/year in the mountain area and the evaporation-transpiration between 850 mm/year in the plain area to 500 mm/year in the high areas. On the other hand, due to a very high variability of weather conditions, droughts, as well as excessive humidity periods, may occur during the year. WatBal is an integrated water balance model developed for assessing the impact of climate changes on a river basin runoff. This model has essentially two main modelling components. The first is the water balance component that uses continuous functions to describe water movement into and out of a conceptualized basin. The second component is the computation of the potential evaporation-transpiration processes. Monthly data series recorded at 5 weather stations and 1 runoff gauging-station during the 1961-2007 period have been used for the calibration of the WatBal model to the local conditions of the area. Finally, the paper focuses on the values of the mean monthly discharges at Adâncata river station on the Prahova River, estimated in the above-mentioned hypotheses. The paper analyses the influence of potential climatic changes, expressed by a wide range of climatic scenarios, upon the average water resources in the Prahova river basin. It has also been taken into consideration the below average water resources, expressed by the minimum-monthly average flow and characteristic to low-water periods as well as the above

  12. Impact of river-lake-groundwater interaction on boundless carbon cycle in continental basin

    Science.gov (United States)

    Nakayama, T.; Shankman, D.

    2012-12-01

    In the Changjiang River in south China, deforestation and land reclamation have induced serious soil erosion and increased floods. Although the Three Gorges Dam (TGD) will provide flood control, the aquatic environment might be changed by discharge control and pollutant loads caused by the deposition of large amounts of sediment in the upper dam (Yang et al., 2006). Some research implies that seepage of groundwater along the lower regions plays important role in maintaining stream flow and after TGD impounding by using natural radionuclides (Dai et al., 2010). It is effective to clarify complicated river-lake-groundwater interaction (Eltahir and Yeh, 1999; Dai et al., 2010), and to evaluate optimum amount of transferred water and environmental consequences in the basin. The authors have so far developed the process-based National Integrated Catchment-based Eco-hydrology (NICE) model (Nakayama, 2008a, 2008b, 2010, 2011a-b, 2012a-c; Nakayama and Fujita, 2010; Nakayama and Hashimoto, 2011; Nakayama and Watanabe, 2004, 2006, 2008a, 2008b; Nakayama et al., 2006, 2007, 2010, 2012), which includes complex interactions between the forest canopy, surface water, the unsaturated zone, aquifers, lakes, and rivers. The objective of this research is to estimate the impact of river-lake-groundwater interaction on hydrologic cycle and to predict the impact of TGD on the hydrologic change in the downstream Dongting and Poyang Lakes region by using a process-based model. Analysis of power spectra in river discharge also helps to understand its complex mechanism. This integrated system also throws some light on the improvement in boundless biogeochemical cycle along terrestrial-aquatic continuum (Cole et al., 2007). References; Cole, J.J. et al., Ecosystems, doi:10.1007/s10021-006-9013-8, 2007. Dai, Z. et al., Hydrogeol. J., 18, 359-369, 2010. Eltahir, E.A.B.& Yeh, P.J.-F., Water Resour. Res., 35(4), 1199-1217, 1999. Nakayama, T., Ecol. Model., doi:10.1016/j.ecolmodel.2008

  13. Cross - Scale Intercomparison of Climate Change Impacts Simulated by Regional and Global Hydrological Models in Eleven Large River Basins

    Science.gov (United States)

    Hattermann, F. F.; Krysanova, V.; Gosling, S. N.; Dankers, R.; Daggupati, P.; Donnelly, C.; Florke, M.; Huang, S.; Motovilov, Y.; Buda, S.; Wada, Y.

    2017-01-01

    Ideally, the results from models operating at different scales should agree in trend direction and magnitude of impacts under climate change. However, this implies that the sensitivity to climate variability and climate change is comparable for impact models designed for either scale. In this study, we compare hydrological changes simulated by 9 global and 9 regional hydrological models (HM) for 11 large river basins in all continents under reference and scenario conditions. The foci are on model validation runs, sensitivity of annual discharge to climate variability in the reference period, and sensitivity of the long-term average monthly seasonal dynamics to climate change. One major result is that the global models, mostly not calibrated against observations, often show a considerable bias in mean monthly discharge, whereas regional models show a better reproduction of reference conditions. However, the sensitivity of the two HM ensembles to climate variability is in general similar. The simulated climate change impacts in terms of long-term average monthly dynamics evaluated for HM ensemble medians and spreads show that the medians are to a certain extent comparable in some cases, but have distinct differences in other cases, and the spreads related to global models are mostly notably larger. Summarizing, this implies that global HMs are useful tools when looking at large-scale impacts of climate change and variability. Whenever impacts for a specific river basin or region are of interest, e.g. for complex water management applications, the regional-scale models calibrated and validated against observed discharge should be used.

  14. The impacts of climate change on water resources in the Second Songhua River Basin, China

    Science.gov (United States)

    Yu, J. S.; Yao, X. L.; Sun, W. C.; Li, Z. J.

    2016-08-01

    The Northeast China Plain is one of the main grain growing regions in China. Due to the high latitude and black soil ecological system, the crop growth in there is vulnerable to climate change, which makes it important to evaluate the influences of climate change on water resources. In this study, the influences of climate change on water resources of a typical basin in northeast China, the Second Songhua River Basin were assessed using the SWAT model. Ensemble downscaled output from sixteen GCMs for A1B emission scenario in 2050s was adopted as the regional climate scenario and was used to drive SWAT model to predict hydrological changes. The prediction shows that mean evapotranspiration of whole basin increases in most time of a year. Stream flow of Fuyu gauging station downstream this basin exhibits a decrease trend from April to June, November and December, and increases in the remaining period of the year. It is indicated that water resources may not be sufficient in spring for irrigation and the possibility of flood in summer may increases, indicating countermeasures should be made to ensure agricultural water use and prevent possible damages of flood on crop.

  15. Impact assessment of measures in the upstream part of Dutch basins to reduce flooding

    NARCIS (Netherlands)

    Querner, E.P.; Rakhorst, M.

    2006-01-01

    Flooding in the northern part of The Netherlands has caused serious economic threats to densely populated areas. Therefore a project has been carried out in a 1200 km2 area to assess the retention of water in the upper parts of river basins as a way to reduce the downstream flooding. The

  16. Deep-sea coral record of human impact on watershed quality in the Mississippi River Basin

    NARCIS (Netherlands)

    Prouty, N.G.; Roark, E.B.; Koenig, A.E.; Demopoulos, A.W.J.; Batista, F.C.; Kocar, B.D.; Selby, D.; McCarthy, M.D.; Mienis, F.

    2014-01-01

    One of the greatest drivers of historical nutrient and sediment transport into the Gulf of Mexico is the unprecedented scale and intensity of land use change in the Mississippi River Basin. These landscape changes are linked to enhanced fluxes of carbon and nitrogen pollution from the Mississippi Ri

  17. Fate of debris from the Borealis basin impact on Mars and from the formation of the Earth-Moon system

    Science.gov (United States)

    Asphaug, Erik; Jackson, Alan P.; Gabriel, Travis; Minton, David A.; Hesselbrock, Andrew

    2016-10-01

    Giant planet-forming collisions can inject significant amounts of debris into the inner solar system. Dynamically the fate of this debris is primarily to re-impact the target body and the other terrestrial planets, defining a post-giant-impact epoch. Giant impact debris leave signatures on the surfaces of terrestrial bodies, influencing and perhaps dominating their early cratering record, and for the largest giant impacts, to intensive surface evolution and even changes in bulk crustal material composition. We use high-resolution N-body simulations to study the fate of debris released by specific giant impacts suggested to have formed the Borealis basin on Mars, and compare it to the fate of debris released by giant impact scenarios for Earth's Moon. We consider how the velocity dependence of Earth-Moon accretion leads to differing velocity distributions of debris-impactors for Earth and Moon, and thus different crater distributions, and study how different assumptions on the size distribution of debris effects these results. We also investigate the influence of collisional grinding within the debris distribution, and the possibility of trapped populations.

  18. Magnetic anomalies in the Imbrium and Schrödinger impact basins: Orbital evidence for persistence of the lunar core dynamo into the Imbrian epoch

    Science.gov (United States)

    Hood, L. L.; Spudis, P. D.

    2016-11-01

    Approximate maps of the lunar crustal magnetic field at low altitudes in the vicinities of the three Imbrian-aged impact basins, Orientale, Schrödinger, and Imbrium, have been constructed using Lunar Prospector and Kaguya orbital magnetometer data. Detectable anomalies are confirmed to be present well within the rims of Imbrium and Schrödinger. Anomalies in Schrödinger are asymmetrically distributed about the basin center, while a single isolated anomaly is most clearly detected within Imbrium northwest of Timocharis crater. The subsurface within these basins was heated to high temperatures at the time of impact and required long time periods (up to 1 Myr) to cool below the Curie temperature for metallic iron remanence carriers (1043 K). Therefore, consistent with laboratory analyses of returned samples, a steady, long-lived magnetizing field, i.e., a former core dynamo, is inferred to have existed when these basins formed. The asymmetrical distribution within Schrödinger suggests partial demagnetization by later volcanic activity when the dynamo field was much weaker or nonexistent. However, it remains true that anomalies within Imbrian-aged basins are much weaker than those within most Nectarian-aged basins. The virtual absence of anomalies within Orientale where impact melt rocks (the Maunder Formation) are exposed at the surface is difficult to explain unless the dynamo field was much weaker during the Imbrian period.

  19. Assessing Climate Change Impacts on Water Resources in the Songhua River Basin

    Directory of Open Access Journals (Sweden)

    Fengping Li

    2016-09-01

    Full Text Available The Songhua River Basin (SRB in Northeast China is one of the areas most sensitive to global climate change because of its high-latitude location. In this study, we conducted a modeling assessment on the potential change of water resources in this region for the coming three decades using the Soil and Water Assessment Tool (SWAT. First, we calibrated and validated the model with historical streamflow records in this basin. Then, we applied the calibrated model for the period from 2020 to 2049 with the projected and downscaled climatic data under two emission scenarios (RCP 4.5 and RCP 8.5. The study results show: (1 The SWAT model performed very well for both the calibration and validation periods in the SRB; (2 The projected temperatures showed a steady, significant increase across the SRB under both scenarios, especially in two sub-basins, the Nenjiang River Basin (NRB and the Lower SRB (LSRB. With regard to precipitation, both scenarios showed a decreasing trend in the NRB and LSRB but an increasing trend in the Upper Songhua River Basin (USRB; and (3, generally, the hydrologic modeling suggested a decreasing trend of streamflow for 2020–2049. Compared to baseline conditions (1980–2009, the streamflow in the NRB and LSRB would decrease by 20.3%–37.8%, while streamflow in the USRB would experience an increase of 9.68%–17.7%. These findings provide relevant insights into future surface water resources, and such information can be helpful for resource managers and policymakers to develop effective eco-environment management plans and strategies in the face of climate change.

  20. Impact of climate Change on Groundwater Recharge in the Tiber River Basin (Central Italy) Using Regional Climate model Outputs

    Science.gov (United States)

    Muluneh, F. B.; Setegn, S. G.; Melesse, A. M.; Fiori, A.

    2011-12-01

    Quantification of the various components of hydrological processes in a watershed remains a challenging topic as the hydrological system is altered by many internal and external drivers. Changes in climate variables can affect the quantity and quality of various components of hydrological cycle. Among others, the local effects of climate change on groundwater resources were not fully studied in different part of the world as compared to the surface water. Moreover, understanding the potential impact of climate change on groundwater is more complex than surface water. The main objective of this study is to analyze the potential impact of climate change on Groundwater recharge in the Tiber River Basin using outputs from Regional Climate model. In this study, a physically-based watershed model called Soil Water Assessment Tool (SWAT) was used to estimate recharge characteristics and its response to climate change in Tiber River Basin (central Italy). The SWAT model was successfully calibrated and validated using observed weather and flow data for the period of 1963-1970 and 1971-1978 respectively. During calibration, the model was highly sensitivity to groundwater flow parameters. Dynamically downscaled rainfall and temperature datasets from ten Regional Climate Models (RCM) archived in 'Prediction of Regional scenarios and Uncertainties for Defining EuropeaN Climate change risks and Effects (PRUDENCE)' were used to force the model to assess the climate change impact on the study area. A quantile-mapping statistical correction procedure was applied to the RCM dataset to correct the inherent systematic biases. The climate change analysis indicated that by the end of 2080s the rainfall was found to decrease nearly up to 40% in dry period and there was an increase in temperature that could reach as high as 3 to 5 oC. By the end of 2080s the ground water recharge shows a decreasing trend as a response to changes in rainfall. However as the timing of both precipitation and

  1. The socioeconomic impacts of the 2004-2008 drought in the Ebro river basin (Spain): A comprehensive and critical assessment

    Science.gov (United States)

    Hernández-Mora, N.; Garrido, A.; Gil, M.

    2012-04-01

    Water scarcity and drought are particularly relevant phenomena in Spain, a country with a Mediterranean climate and intense pressure on existing water resources. Spain's drought management policies have evolved significantly over time, and today Spain is at the forefront of drought management and mitigation planning in Europe. However, drought management policies are not informed by comprehensive or accurate estimations of the socioeconomic impacts of drought, nor by the efficiency or efficacy of drought management and mitigation measures. Previous studies attempting to estimate on the impacts of drought are based on direct economic users of water, primarily irrigated agriculture and hydropower. Existing analyses do not take into consideration the impacts on other economic sectors, such as recreational uses, which have a growing importance from a socioeconomic perspective. Additionally, the intangible or non-market impacts (on social welfare and wellbeing and on the environment) are not considered or measured, although they can be significant. This paper presents the mid-point results of the PREEMPT project (Policy relevant assessment of the socioeconomic effects of droughts and floods, ECHO - grant agreement # 070401/2010/579119/SUB/C4), an effort to provide a comprehensive assessment of the socioeconomic impacts of the 2004-2008 drought in the Ebro river basin. The study gathers existing information on direct and indirect economic impacts of drought on different sectors, completing existing gaps and comparing the results of studies that use different methodologies. It also estimates the welfare losses resulting from domestic water use restrictions and environmental degradation as a result of the drought using a value transfer approach from results derived from value choice experiments developed for other Spanish and international river basins. Results indicate that there is a clear need to improve our knowledge of the direct and indirect impacts of drought and to

  2. Impacts of Climate Change on Regulated Streamflow, Hydrologic Extremes, Hydropower Production, and Sediment Discharge in the Skagit River Basin

    Science.gov (United States)

    Lee, Se-Yeun; Hamlet, Alan F.; Grossman, Eric E.

    2016-01-01

    Previous studies have shown that the impacts of climate change on the hydrologic response of the Skagit River are likely to be substantial under natural (i.e. unregulated) conditions. To assess the combined effects of changing natural flow and dam operations that determine impacts to regulated flow, a new integrated daily-time-step reservoir operations model was constructed for the Skagit River Basin. The model was used to simulate current reservoir operating policies for historical flow conditions and for projected flows for the 2040s (2030–2059) and 2080s (2070–2099). The results show that climate change is likely to cause substantial seasonal changes in both natural and regulated flow, with more flow in the winter and spring, and less in summer. Hydropower generation in the basin follows these trends, increasing (+ 19%) in the winter/ spring, and decreasing (- 29%) in the summer by the 2080s. The regulated 100-year flood is projected to increase by 23% by the 2040s and 49% by the 2080s. Peak winter sediment loading in December is projected to increase by 335% by the 2080s in response to increasing winter flows, and average annual sediment loading increases from 2.3 to 5.8 teragrams (+ 149%) per year by the 2080s. Regulated extreme low flows (7Q10) are projected to decrease by about 30% by the 2080s, but remain well above natural low flows. Both current and proposed alternative flood control operations are shown to be largely ineffective in mitigating increasing flood risks in the lower Skagit due to the distribution of flow in the basin during floods.

  3. Origin of strong lunar magnetic anomalies: Further mapping and examinations of LROC imagery in regions antipodal to young large impact basins

    Science.gov (United States)

    Hood, Lon L.; Richmond, Nicola C.; Spudis, Paul D.

    2013-06-01

    The existence of magnetization signatures and landform modification antipodal to young lunar impact basins is investigated further by (a) producing more detailed regional crustal magnetic field maps at low altitudes using Lunar Prospector magnetometer data; and (b) examining Lunar Reconnaissance Orbiter Wide Angle Camera imagery. Of the eight youngest lunar basins, five are found to have concentrations of relatively strong magnetic anomalies centered within 10° of their antipodes. This includes the polar Schrödinger basin, which is one of the three youngest basins and has not previously been investigated in this context. Unusual terrain is also extensively present near the antipodes of the two largest basins (Orientale and Imbrium) while less pronounced manifestations of this terrain may be present near the antipodes of Serenitatis and Schrödinger. The area near the Imbrium antipode is characterized by enhanced surface thorium abundances, which may be a consequence of antipodal deposition of ejecta from Imbrium. The remaining three basins either have antipodal regions that have been heavily modified by later events (Hertzsprung and Bailly) or are not clearly recognized to be a true basin (Sikorsky-Rittenhouse). The most probable source of the Descartes anomaly, which is the strongest isolated magnetic anomaly, is the hilly and furrowed Descartes terrain near the Apollo 16 landing site, which has been inferred to consist of basin ejecta, probably from Imbrium according to one recent sample study. A model for the origin of both the modified landforms and the magnetization signatures near lunar basin antipodes involving shock effects of converging ejecta impacts is discussed.

  4. Impact of climate change on sediment yield in the Mekong River basin: a case study of the Nam Ou basin, Lao PDR

    Directory of Open Access Journals (Sweden)

    B. Shrestha

    2013-01-01

    Full Text Available This paper evaluates the impact of climate change on sediment yield in the Nam Ou basin located in northern Laos. Future climate (temperature and precipitation from four general circulation models (GCMs that are found to perform well in the Mekong region and a regional circulation model (PRECIS are downscaled using a delta change approach. The Soil and Water Assessment Tool (SWAT is used to assess future changes in sediment flux attributable to climate change. Results indicate up to 3.0 °C shift in seasonal temperature and 27% (decrease to 41% (increase in seasonal precipitation. The largest increase in temperature is observed in the dry season while the largest change in precipitation is observed in the wet season. In general, temperature shows increasing trends but changes in precipitation are not unidirectional and vary depending on the greenhouse gas emission scenarios (GHGES, climate models, prediction period and season. The simulation results show that the changes in annual stream discharges are likely to range from a 17% decrease to 66% increase in the future, which will lead to predicted changes in annual sediment yield ranging from a 27% decrease to about 160% increase. Changes in intra-annual (monthly discharge as well as sediment yield are even greater (−62 to 105% in discharge and −88 to 243% in sediment yield. A higher discharge and sediment flux are expected during the wet seasons, although the highest relative changes are observed during the dry months. The results indicate high uncertainties in the direction and magnitude of changes of discharge as well as sediment yields due to climate change. As the projected climate change impact on sediment varies remarkably between the different climate models, the uncertainty should be taken into account in both sediment management and climate change adaptation.

  5. The Impact of Para Rubber Expansion on Streamflow and Other Water Balance Components of the Nam Loei River Basin, Thailand

    Directory of Open Access Journals (Sweden)

    Winai Wangpimool

    2016-12-01

    Full Text Available At present, Para rubber is an economical crop which provides a high priced product and is in demand by global markets. Consequently, the government of Thailand is promoting the expansion of Para rubber plantations throughout the country. Traditionally, Para rubber was planted and grown only in the southern areas of the country. However, due to the Government’s support and promotion as well as economic reasons, the expansion of Para rubber plantations in the northeast has increased rapidly. This support has occurred without accounting for suitable cultivation of Para rubber conditions, particularly in areas with steep slopes and other factors which have significant impacts on hydrology and water quality. This study presents the impacts of Para rubber expansion by applying the Soil and Water Assessment Tool (SWAT hydrological model on the hydrology and water balance of the Nam Loei River Basin, Loei Province. The results showed that the displacement of original local field crops and disturbed forest land by Para rubber production resulted in an overall increase of evapotranspiration (ET of roughly 3%. The major factors are the rubber canopy and precipitation. Moreover, the water balance results showed an annual reduction of about 3% in the basin average water yield, especially during the dry season.

  6. Investigation of climate change impact on water resources for an Alpine basin in northern Italy: implications for evapotranspiration modeling complexity.

    Science.gov (United States)

    Ravazzani, Giovanni; Ghilardi, Matteo; Mendlik, Thomas; Gobiet, Andreas; Corbari, Chiara; Mancini, Marco

    2014-01-01

    Assessing the future effects of climate change on water availability requires an understanding of how precipitation and evapotranspiration rates will respond to changes in atmospheric forcing. Use of simplified hydrological models is required because of lack of meteorological forcings with the high space and time resolutions required to model hydrological processes in mountains river basins, and the necessity of reducing the computational costs. The main objective of this study was to quantify the differences between a simplified hydrological model, which uses only precipitation and temperature to compute the hydrological balance when simulating the impact of climate change, and an enhanced version of the model, which solves the energy balance to compute the actual evapotranspiration. For the meteorological forcing of future scenario, at-site bias-corrected time series based on two regional climate models were used. A quantile-based error-correction approach was used to downscale the regional climate model simulations to a point scale and to reduce its error characteristics. The study shows that a simple temperature-based approach for computing the evapotranspiration is sufficiently accurate for performing hydrological impact investigations of climate change for the Alpine river basin which was studied.

  7. Impact of climate change and variability on water resources in Heihe River Basin

    Institute of Scientific and Technical Information of China (English)

    NHANGJishi; KANGErsi; LANYongchao; CHENRensheng

    2003-01-01

    Studies indicate that the climate has experienced a dramatic change in the Heihe River Basin with scope of temperature rise reaching 0.5-1 .1℃ in the 1990s compared to the mean value of the period 1960-1990, precipitation increased 18.5 mm in the 1990s compared to the 1950s, and 6.5mm in the 1990s compared to the mean value of the period 1960-1990, water resources decreased 2.6 × l03 m3 in the 1990s compared to the 1950s, and 0.4 × l08 m3 in the 1990s compared to the mean value of the period 1960-1990. These changes have exerted a greater effect on the local environment and socio-economy, and also made the condition worsening in water resources utilizations in the Heihe Rver Basin.

  8. Climate change impacts on snow water availability in the Euphrates-Tigris basin

    OpenAIRE

    Özdoğan, M.

    2011-01-01

    This study investigates the effects of projected climate change on snow water availability in the Euphrates-Tigris basin using the Variable Infiltration Capacity (VIC) macro scale hydrologic model and a set of regional climate-change outputs from 13 global circulation models (GCMs) forced with two greenhouse gas emission scenarios for two time periods in the 21st century (2050 and 2090). The hydrologic model produces a reasonable simulation of seasonal and spatial variation in snow cover and ...

  9. Climate change impacts on snow water availability in the Euphrates-Tigris basin

    OpenAIRE

    Özdoğan, M.

    2011-01-01

    This study investigates the effects of projected climate change on snow water availability in the Euphrates-Tigris basin using the Variable Infiltration Capacity (VIC) macro scale hydrologic model and a set of regional climate-change outputs from 13 global circulation models (GCMs) forced with two greenhouse gas emission scenarios for two time periods in the 21st century (2050 and 2090). The hydrologic model produces a reasonable simulation of seasonal and spatial variation ...

  10. Transitional properties of droughts and related impacts of climate indices in the Pearl River basin, China

    Science.gov (United States)

    Xiao, Mingzhong; Zhang, Qiang; Singh, Vijay P.; Liu, Lin

    2016-03-01

    Drought is the natural hazard poorly understood so far due to various mechanisms behind. Moreover, disastrous effects of drought on human society necessitate accurate forecasting of drought behaviors. In this case, to improve forecasting of drought in the Pearl River basin, a trivariate copula model has been developed and used to include the El Nino Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), Indian Ocean Dipole (IOD) and Pacific Decadal Oscillation (PDO) into model structure of Markov chain. The Standardized Precipitation Evapotranspiration Index (SPEI) has been used to monitor the drought in this study. Comparison with the preliminary correlation analysis between each month climate index and SPEI series indicated that the trivariate copula performs satisfactorily well in evaluation of influences of climate indices on the transition probabilities of drought. It is considered that the region with the negative vertical velocity is dominated by more precipitation and vice versa. Moreover, field patterns of 500 hPa vertical velocity anomalies related to each climate index have further corroborated the influences of climate indices on the drought behaviors. Besides, the mean extreme drought durations under different conditions of each climate index have also been investigated in this study. Results indicated that the mean extreme drought duration tends to be longer in the western part of the Pearl River basin during positive phase of ENSO while tends to be shorter during the positive phase of NAO and vice versa; in the central part of the Pearl River basin, the mean extreme drought duration tends to be shorter during the positive phase of ENSO, NAO and PDO while tends to be longer during the positive episode of IOD, and vice versa; in the eastern part of the Pearl River basin, the mean extreme drought duration tends to be shorter during the positive episode of ENSO and PDO, and vice versa. This study sheds new light on transitional behaviors of

  11. The impact of sea breeze under different synoptic patterns on air pollution within Athens basin.

    Science.gov (United States)

    Mavrakou, Thaleia; Philippopoulos, Kostas; Deligiorgi, Despina

    2012-09-01

    Air quality in densely populated urban coastal areas is directly related to the coupling of the synoptic and the local scale flows. The dispersion conditions within Athens basin, under the influence of different meteorological forcings, lead to distinct spatio-temporal air pollution patterns. The aim of the current observational research is to identify and examine the effect of sea breeze under different atmospheric circulation patterns on air pollution levels for a one-year study period (2007). The study employs surface pressure maps, routine meteorological observations at two coastal sites and nitrogen monoxide (NO), nitrogen dioxide (NO(2)) and ozone (O(3)) concentrations from a network of four air quality stations within the Athens basin. A three-step methodology is applied that incorporates a set of criteria for classifying atmospheric circulation and identifying sea breeze events under each circulation pattern. Two types of sea breeze development are identified (pure sea breeze-PSB and modified sea breeze-MSB) with distinct characteristics. Sea breeze is found to develop more frequently under offshore compared to onshore and parallel to the shoreline background flows. Poor dispersion conditions (high nitrogen oxides-NO(x) and O(3) concentrations) are connected to the pure sea breeze cases and to those cases where sea breeze interacts with a moderate northerly flow during the warm period. The levels of NO(x) and O(3) for the northern Athens basin area are found to be significantly higher during the sea breeze days compared to the Etesian days. Regarding the diurnal variation of ozone for the sea breeze days, peak concentrations and higher intra-daily ranges are observed. Day-to-day pollution accumulation (build-up effect) is measured for O(3) at the northern stations in the Athens basin.

  12. Hydrogeological processes in the Paris Basin: climate and geomorphologic impacts of the last five million years

    Energy Technology Data Exchange (ETDEWEB)

    Jost, A.; Violette, S.; Goncalves, J.; Marsily, G. de [Universite Pierre et Marie Curie, Sisyphe (UNIR CNRS 7619), 75 - Paris (France); Ledoux, E. [Ecole des Mines de Paris, Sisyphe (UNIR CNRS 7619, CIG, ENSMP), 77 - Fontainebleau (France); Guyomard, Y.; Robin, C.; Bonnet, St.; Guillocheau, F. [Rennes-1 Univ., Geosciences Rennes (UNIR CNRS 6118), 35 (France); Kageyama, M.; Ramstein, G. [Laboratoire des Sciences du Climat et de l' Environnement (UMR CEA-CNRS), Orme des Merisiers, 91 - Gif sur Yvette (France); Fauquette, S. [Montpellier-2 Univ., Institut des Sciences de l' Evolution de Montpellier (UNIR CNRS 5554) 34 (France); Favreb, E.; Such, J.P. [Universite Claude Bernard Lyon-1, PaleoEnvironnements et PaleobioSphere (UNIR CNRS 5125), 69 - Villeurbanne (France); Michelot, J.L. [OrsayTerre, FRE 2566, Faculte des Sciences, 91 - Orsay (France)

    2005-07-01

    The aim of the present study is to investigate the response of the Paris basin aquifer system to variations in its hydrodynamic boundary conditions on a time scale of several million years, trying to determine if the system has kept the memory of these past changes. Recent changes at a boundary are more especially of importance when considering its effects on groundwater flow in low-diffusivity regions, as it can generate a lasting transient flow, potentially responsible for abnormal pressures creation. For the purpose of this work, a 3D transient modelling of the Paris basin groundwater system has been developed using the code NEWSAM (ENSMP). The geometry and hydrodynamic input data of the model originate from previous studies on a basin model, NEWBAS (ENSMP), built to simulate the 248 My geological history of the basin. Both a geomorphologic and climatic scenarios have been established. Geomorphologic evolution is deduced from digital elevation model analysis, which allows to reconstruct the paleo-topography and measure river-valley incision and alpine orogenesis. Climate forcing results from a suite of paleo-climate modelling experiments using the LMDz atmospheric general circulation model (IPSL) with a refined spatial resolution centered on Paris, for the present, the Last Glacial Maximum (21 kyr BP) and the Middle Pliocene (3 My). The water balance is computed by a distributed hydrologic model, MODSUR (ENSMP). We present the simulated evolution of the transfers in the aquifer system in response to the altered boundary conditions induced by atmospheric and geomorphologic forcing, in the course of the last five million years. (authors)

  13. The Beaufort Gyre variation and its impacts on the Canada Basin in 2003-2012

    Institute of Scientific and Technical Information of China (English)

    ZHONG Wenli; ZHAO Jinping; SHI Jiuxin; CAO Yong

    2015-01-01

    The Beaufort Gyre (BG) was spun up in the last decade which is an important factor in regulating the variation of the upper ocean. The heat content and freshwater content of the upper ocean increased gradually in the Canada Basin, as did momentum input. Both the geostrophic wind curl and freshwater content could contribute to the spin-up of BG. However, even though there is no change of the wind field the increasing freshwater alone could result in the spin-up of BG. In this study we show that the Pacific Water is difficult to flow into the central basin as the BG spins up and the maximum temperature of the Pacific Summer Water (PSW) experienced a dramatic decrease inside the BG in 2005 and 2009 due to a change of flow pathway of PSW. The enhancement of Ekman Pumping (EP) contributed to the deepening of the Pacific Winter Water by piling up more freshwater. This change of water column dynamics has also contributed to the deepening ofthe Atlantic Water core after 2007. The EP decreased significantly in 2012 (indicating a spin down of BG) and the direction of Ekman transport turned to the north, which favoured the release of freshwater that had resided in the basin for years.

  14. Impact of climatic and environmental changes on flood-duration-frequencies in the Fengle Rriver (YangTze Basin, China)

    Science.gov (United States)

    Salles, Christian; Chu, Yin; Tournoud, Marie-George; Ou, Mengli; Perrin, Jean-Louis; Cres, François-Noël; Ma, Youhua

    2016-04-01

    Future water management challenges such as flood risk are highly relevant to climate and land use changes. Climate change is expected to lead to an ongoing intensification of effects on changes in precipitation and evapotranspiration which could exacerbate flooding issues. Land use changes, modifications of agricultural practices and urbanization alter the apportionment of the different hydrological processes at the basin scale and could significantly affect the seasonality of streamflow. At the local scale, the consequences of climate and land use changes on flood occurrence and magnitude are a major issue for the economic development and management policy of basin area. This study apply a methodology for investigating the potential consequences of land use ,as well as precipitation and temperature changes on flood occurrence, duration and magnitude, accounting for uncertainties in scenario data and hydrological model parameters. The discharge time series predicted for the future were simulated from a calibrated and validated distributed hydrological model. The model was run from inputs which are -predicted rainfall time series based on scenarios of changes identified from a literature review, -future evapotranspiration rates assessed from temperature changes identified from a literature review -and scenarios of land-use changes The study area, the Fengle River basin (1500 km2), is located in the northeast part of Yangtze basin. The river is one of the main tributaries of the Chao Lake, the fifth largest natural lake of China. The lake catchment is 9130 km2 in area, including the city of Hefei and a large extent of agricultural and rural areas. Many changes are expected in land use and agricultural practices in the future, due to the touristic appeal of the Chao Lake shore and the growth of the city of Hefei. Climate changes are also expected in this region, with a high impact on rainfall regime. In the current period heavy storms and floods occur predominantly

  15. The predictability of reported drought events and impacts in the Ebro Basin using six different remote sensing data sets

    Science.gov (United States)

    Linés, Clara; Werner, Micha; Bastiaanssen, Wim

    2017-09-01

    The implementation of drought management plans contributes to reduce the wide range of adverse impacts caused by water shortage. A crucial element of the development of drought management plans is the selection of appropriate indicators and their associated thresholds to detect drought events and monitor the evolution. Drought indicators should be able to detect emerging drought processes that will lead to impacts with sufficient anticipation to allow measures to be undertaken effectively. However, in the selection of appropriate drought indicators, the connection to the final impacts is often disregarded. This paper explores the utility of remotely sensed data sets to detect early stages of drought at the river basin scale and determine how much time can be gained to inform operational land and water management practices. Six different remote sensing data sets with different spectral origins and measurement frequencies are considered, complemented by a group of classical in situ hydrologic indicators. Their predictive power to detect past drought events is tested in the Ebro Basin. Qualitative (binary information based on media records) and quantitative (crop yields) data of drought events and impacts spanning a period of 12 years are used as a benchmark in the analysis. Results show that early signs of drought impacts can be detected up to 6 months before impacts are reported in newspapers, with the best correlation-anticipation relationships for the standard precipitation index (SPI), the normalised difference vegetation index (NDVI) and evapotranspiration (ET). Soil moisture (SM) and land surface temperature (LST) offer also good anticipation but with weaker correlations, while gross primary production (GPP) presents moderate positive correlations only for some of the rain-fed areas. Although classical hydrological information from water levels and water flows provided better anticipation than remote sensing indicators in most of the areas, correlations were

  16. Evaluation of the potential impact of climate changes on groundwater recharge in Karkheh river basin (Khuzestan, Iran)

    Science.gov (United States)

    Abrishamchi, A.; Beigi, E.; Tajrishy, M.; Abrishamchi, A.

    2009-12-01

    Groundwater is an important natural resource for human beings and ecosystems, especially in arid semi arid regions with scarce water resources and high climate variability. This vital resource is under stress in terms of both quantity and quality due to increased demands as well as the drought. Wise groundwater management requires vulnerability and susceptibility assessment of groundwater resources to natural and anthropogenic phenomena such as drought, over-abstraction and quality deterioration both in the current climatic situation and in the context of climate change. There is enough evidence that climate change is expected to affect all elements of hydrologic cycle and have negative effects on water resources due to increased variability in extreme hydrologic events of droughts and floods. .In this study impact of climate change on groundwater recharge in Karkheh river basin in province of Khuzestan, Iran, has been investigated using a physically-based methodology that can be used for predicting both temporal and spatial varying groundwater recharge. To ensure the sustainability of the land and water resources developments, assessment of the possible impacts of climate change on hydrology and water resources in the basin is necessary. Quantifying groundwater recharge is essential for management of groundwater resources. Recharge was estimated by using the hydrological evaluation of landfill performance (HELP3) water budget model. Model’s parameters were calibrated and validated using observational data in 1990-1998. The impact of climate change was modeled using downscaled precipitation and temperature from runs of CGCM2 model. These data were derived from two scenarios, A2 and B2 for three periods: 2010-2039, 2040-2069, and 2070-2099. Results of the study indicate that due to global warming evapotranspiration rates will increase and winter-precipitation will fall, spring-snowmelt will shift toward winter and consequently it will cause recharge to increase

  17. Reservoir impacts downstream in highly regulated river basins: the Ebro delta and the Guadalquivir estuary in Spain

    Science.gov (United States)

    Polo, María J.; Rovira, Albert; García-Contreras, Darío; Contreras, Eva; Millares, Agustín; Aguilar, Cristina; Losada, Miguel A.

    2016-05-01

    Regulation by reservoirs affects both the freshwater regime and the sediment delivery at the area downstream, and may have a significant impact on water quality in the final transitional water bodies. Spain is one the countries with more water storage capacity by reservoirs in the world. Dense reservoir networks can be found in most of the hydrographic basins, especially in the central and southern regions. The spatial redistribution of the seasonal and annual water storage in reservoirs for irrigation and urban supply, mainly, has resulted in significant changes of water flow and sediment load regimes, together with a fostered development of soil and water uses, with environmental impacts downstream and higher vulnerability of these areas to the sea level rise and drought occurrence. This work shows these effects in the Guadalquivir and the Ebro River basins, two of the largest regulated areas in Spain. The results show a 71 % decrease of the annual freshwater input to the Guadalquivir River estuary during 1930-2014, an increase of 420 % of the irrigated area upstream the estuary, and suspended sediment loads up to 1000 % the initial levels. In the Ebro River delta, the annual water yield has decreased over a 30 % but, on the contrary, the big reservoirs are located in the main stream, and the sediment load has decreased a 99 %, resulting in a delta coastal regression up to 10 m per year and the massive presence of macrophytes in the lower river. Adaptive actions proposed to face these impacts in a sea level rise scenario are also analyzed.

  18. EVIDENCE OF NEOTECTONIC IMPACT ON A LARGE SEDIMENTARY BASIN BETWEEN TIBETAN PLATEAU AND GOBI ALTAY,NW CHINA

    Institute of Scientific and Technical Information of China (English)

    K.ttartmann; B.Wünnemann; Hucai Zhang

    2009-01-01

    The Ejina(Gaxun Nur)Basin-enclosed by the Tibetan Plateau in the south and the Gobi Altay in the north has continuously evolved as a strong continental endorheic depositional environment.Medium scale geomorphological mapping by Landsat-and Corona-Images as well as SRTM-topographic data,combined with field-surveys and geophysical investigation provides evidence for tectonic impact on sedimentary processes during the Late Quaternary.Analyses of SRTM-Data and Landsat-Images reveal a system of up to 20m high inverted channels developed on the inactive eastern part of the large Hei river drainage delta south of the ancient lake Juyanze.The complex evolution of these landforms requires a relative lowering of the lake basin at least two times since the last 40ka.A 26m high cliff section of gravel-covered lake sediments within the Juyanze paleolake indicates a strong subsidence of the lake bottom of 10m/1000yrs since 18kaB.P.North of Ejina river oasis a distinct north-south striking scarp up to 13m high constitutes the eastern margin of the Gaxun Nur.Palaeodrainage channels derived from the Gobi Altay.They display a sinistral offset of some decametres along a set of WE-trending faults.The rhombic shape of the modern dry Gaxun Nur,fossil cliffs,well preserved beach ridges along the margins of the palaeolake system as well as gravel covered topsets of lacustrine sediments indicate local displacements of morphological features.The displacements of lake sediments at the southern margin of the modern Gaxun Nut Basin imply a subsidence of at least 0.81m/1000 yrs since 25kaB.P.as a result of a pull-apart development due to the left stepping faults in a sinistral system.

  19. Using an ensemble of regional climate models to assess climate change impacts on water scarcity in European river basins.

    Science.gov (United States)

    Gampe, David; Nikulin, Grigory; Ludwig, Ralf

    2016-12-15

    Climate change will likely increase pressure on the water balances of Mediterranean basins due to decreasing precipitation and rising temperatures. To overcome the issue of data scarcity the hydrological relevant variables total runoff, surface evaporation, precipitation and air temperature are taken from climate model simulations. The ensemble applied in this study consists of 22 simulations, derived from different combinations of four General Circulation Models (GCMs) forcing different Regional Climate Models (RCMs) and two Representative Concentration Pathways (RCPs) at ~12km horizontal resolution provided through the EURO-CORDEX initiative. Four river basins (Adige, Ebro, Evrotas and Sava) are selected and climate change signals for the future period 2035-2065 as compared to the reference period 1981-2010 are investigated. Decreased runoff and evaporation indicate increased water scarcity over the Ebro and the Evrotas, as well as the southern parts of the Adige and the Sava, resulting from a temperature increase of 1-3° and precipitation decrease of up to 30%. Most severe changes are projected for the summer months indicating further pressure on the river basins already at least partly characterized by flow intermittency. The widely used Falkenmark indicator is presented and confirms this tendency and shows the necessity for spatially distributed analysis and high resolution projections. Related uncertainties are addressed by the means of a variance decomposition and model agreement to determine the robustness of the projections. The study highlights the importance of high resolution climate projections and represents a feasible approach to assess climate impacts on water scarcity also in regions that suffer from data scarcity.

  20. Assessment of climate change impact on hydrological extremes in two source regions of the Nile River Basin

    Directory of Open Access Journals (Sweden)

    M. T. Taye

    2011-01-01

    Full Text Available The potential impact of climate change was investigated on the hydrological extremes of Nyando River and Lake Tana catchments, which are located in two source regions of the Nile River basin. Climate change scenarios were developed for rainfall and potential evapotranspiration (ETo, considering 17 General Circulation Model (GCM simulations to better understand the range of possible future change. They were constructed by transferring the extracted climate change signals to the observed series using a frequency perturbation downscaling approach, which accounts for the changes in rainfall extremes. Projected changes under two future SRES emission scenarios A1B and B1 for the 2050s were considered. Two conceptual hydrological models were calibrated and used for the impact assessment. Their difference in simulating the flows under future climate scenarios was also investigated.

    The results reveal increasing mean runoff and extreme peak flows for Nyando catchment for the 2050s while unclear trend is observed for Lake Tana catchment for mean volumes and high/low flows. The hydrological models for Lake Tana catchment, however, performed better in simulating the hydrological regimes than for Nyando, which obviously also induces a difference in the reliability of the extreme future projections for both catchments. The unclear impact result for Lake Tana catchment implies that the GCM uncertainty is more important for explaining the unclear trend than the hydrological models uncertainty. Nevertheless, to have a better understanding of future impact, hydrological models need to be verified for their credibility of simulating extreme flows.

  1. Predicting the downstream impact of ensembles of small reservoirs with special reference to the Volta Basin, West Africa

    Science.gov (United States)

    van de Giesen, N.; Andreini, M.; Liebe, J.; Steenhuis, T.; Huber-Lee, A.

    2005-12-01

    After a strong reduction in investments in water infrastructure in Sub-Saharan Africa, we now see a revival and increased interest to start water-related projects. The global political willingness to work towards the UN millennium goals are an important driver behind this recent development. Large scale irrigation projects, such as were constructed at tremendous costs in the 1970's and early 1980's, are no longer seen as the way forward. Instead, the construction of a large number of small, village-level irrigation schemes is thought to be a more effective way to improve food production. Such small schemes would fit better in existing and functioning governance structures. An important question now becomes what the cumulative (downstream) impact is of a large number of small irrigation projects, especially when they threaten to deplete transboundary water resources. The Volta Basin in West Africa is a transboundary river catchment, divided over six countries. Of these six countries, upstream Burkina Faso and downstream Ghana are the most important and cover 43% and 42% of the basin, respectively. In Burkina Faso (and also North Ghana), small reservoirs and associated irrigation schemes are already an important means to improve the livelihoods of the rural population. In fact, over two thousand such schemes have already been constructed in Burkina Faso and further construction is to be expected in the light of the UN millennium goals. The cumulative impact of these schemes would affect the Akosombo Reservoir, one of the largest manmade lakes in the world and an important motor behind the economic development in (South) Ghana. This presentation will put forward an analytical framework that allows for the impact assessment of (large) ensembles of small reservoirs. It will be shown that despite their relatively low water use efficiencies, the overall impact remains low compared to the impact of large dams. The tools developed can be used in similar settings elsewhere

  2. Integrated Modeling to Assess the Impacts of Changes in Climate and Socio Economics on Agriculture in the Columbia River Basin

    Science.gov (United States)

    Rajagopalan, K.; Chinnayakanahalli, K.; Adam, J. C.; Malek, K.; Nelson, R.; Stockle, C.; Brady, M.; Dinesh, S.; Barber, M. E.; Yorgey, G.; Kruger, C.

    2012-12-01

    The objective of this work is to assess the impacts of climate change and socio economics on agriculture in the Columbia River basin (CRB) in the Pacific Northwest region of the U.S. and a portion of Southwestern Canada. The water resources of the CRB are managed to satisfy multiple objectives including agricultural withdrawal, which is the largest consumptive user of CRB water with 14,000 square kilometers of irrigated area. Agriculture is an important component of the region's economy, with an annual value over 5 billion in Washington State alone. Therefore, the region is relevant for applying a modeling framework that can aid agriculture decision making in the context of a changing climate. To do this, we created an integrated biophysical and socio-economic regional modeling framework that includes human and natural systems. The modeling framework captures the interactions between climate, hydrology, crop growth dynamics, water management and socio economics. The biophysical framework includes a coupled macro-scale physically-based hydrology model (the Variable Infiltration Capacity, VIC model), and crop growth model (CropSyst), as well as a reservoir operations simulation model. Water rights data and instream flow target requirements are also incorporated in the model to simulate the process of curtailment during water shortage. The economics model informs the biophysical model of the short term agricultural producer response to water shortage as well as the long term agricultural producer response to domestic growth and international trade in terms of an altered cropping pattern. The modeling framework was applied over the CRB for the historical period 1976-2006 and compared to a future 30-year period centered on the 2030s. Impacts of climate change on irrigation water availability, crop irrigation demand, frequency of curtailment, and crop yields are quantified and presented. Sensitivity associated with estimates of water availability, irrigation demand, crop

  3. Impacts of golden alga Prymnesium parvum on fish populations in reservoirs of the upper Colorado River and Brazos River basins, Texas

    Science.gov (United States)

    VanLandeghem, Matthew M.; Farooqi, Mukhtar; Farquhar, B.; Patino, Reynaldo

    2013-01-01

    Several reservoirs in the upper Colorado River and Brazos River basins in Texas have experienced toxic blooms of golden alga Prymnesium parvum and associated fish kills since 2001. There is a paucity of information, however, regarding the population-level effects of such kills in large reservoirs, species-specific resistance to or recovery from kills, or potential differences in the patterns of impacts among basins. We used multiple before-after, control-impact analysis to determine whether repeated golden alga blooms have led to declines in the relative abundance and size structure of fish populations. Sustained declines were noted for 9 of 12 fish species surveyed in the upper Colorado River, whereas only one of eight species was impacted by golden alga in the Brazos River. In the upper Colorado River, White Bass Morone chrysops, White Crappie Pomoxis annularis, Largemouth Bass Micropterus salmoides, Bluegill Lepomis macrochirus, River Carpsucker Carpiodes carpio, Freshwater Drum Aplodinotus grunniens, Channel Catfish Ictalurus punctatus, Flathead Catfish Pylodictis olivaris, and Blue Catfish I. furcatus exhibited sustained declines in relative abundance, size structure, or both; Gizzard Shad Dorosoma cepedianum, Longnose Gar Lepisosteus osseus, and Common Carp Cyprinus carpio did not exhibit those declines. In the Brazos River, only the relative abundance of Blue Catfish was impacted. Overall, toxic golden alga blooms can negatively impact fish populations over the long-term, but the patterns of impact can vary considerably among river basins and species. In the Brazos River, populations of most fish species appear to be healthy, suggesting a positive angling outlook for this basin. In the upper Colorado River, fish populations have been severely impacted, and angling opportunities have been reduced. Basin-specific management plans aimed at improving water quality and quantity will likely reduce bloom intensity and allow recovery of fish populations to the

  4. Neotectonic impact and Palaeohydrology of Gaxun Nur Basin (NW China) during the Late Quaternary

    Science.gov (United States)

    Hartmann, K.; Wünnemann, B.; Zhang, H.

    2009-04-01

    The Gaxun Nur Basin - enclosed by the Tibetan Plateau in the south and the Gobi Altay in the north - has continuously evolved as a strong continental endorheic depositional environment for the last 250,000 years. The Hei River drainage system originates in the Qilian Shan (>5,000 m a.s.l.) fed a crescent-shaped series of terminal lakes at its far end (Gaxun Nur, Sogo Nur and Juyanze). Large scale geomorphological mapping from Landsat-data, Corona-Images and SRTM - elevation data shows widespread features of faults within the whole basin (Hartmann 2003). Main lineaments have been proved by geophysical investigations (Hoelz et al. 2007). Geomorphological discontinuities (e.g. inverted channels, concave alluvial fans,..) in order of their underlying processes of fluvial, aeolian and lacustrine origin allow a stratigraphic placement. Dating of lake deposits within and between geomorphological units yield the chronological frame of tectonic movement and environmental change as well. The 230m long core D100 in the centre of the basin (ca. 28,000 km²) shows the start-up of more or less continuous lacustrine deposition at ca. 250,000 yrs BP. A large set of radiocarbon datings of the upper ca. 90m suggests an increasing subsidence rate since MIS 4 within the whole basin. (Wünnemann et al. 2007) A 26 m high cliff section of gravel-covered lake sediments within the Juyanze Palaeolake indicates a strong subsidence of the lake bottom of 3.6m/1000yrs since 18 kyrs BP. Geophysical investigation indicates a lowering of the western basin along a fault system as a continuation of a duplex structure developed further south at Gurinai depression (Hoelz et al. 2007). The rhombic shape of the modern dry Gaxun Nur, fossil cliffs, well preserved beach ridges and gravel covered top-sets of lacustrine sediments indicate local displacements of morphological features. Flat flower structures along a WNW-trending fault indicate young tectonic movements related to the Tian Shan fault system

  5. AIR QUALITY IMPACTS OF LIQUEFIED NATURAL GAS IN THE SOUTH COAST AIR BASIN OF CALIFORNIA

    Energy Technology Data Exchange (ETDEWEB)

    Carerras-Sospedra, Marc; Brouwer, Jack; Dabdub, Donald; Lunden, Melissa; Singer, Brett

    2011-07-01

    The effects of liquefied natural gas (LNG) on pollutant emission inventories and air quality in the South Coast Air Basin of California were evaluated using recent LNG emission measurements by Lawrence Berkeley National Laboratory and the Southern California Gas Company (SoCalGas), and with a state-of-the-art air quality model. Pollutant emissions can be affected by LNG owing to differences in composition and physical properties, including the Wobbe index, a measure of energy delivery rate. This analysis uses LNG distribution scenarios developed by modeling Southern California gas flows, including supplies from the LNG receiving terminal in Baja California, Mexico. Based on these scenarios, the projected penetratino of LNG in the South Coast Air Basin is expected to be limited. In addition, the increased Wobbe index of delivered gas (resulting from mixtures of LNG and conventional gas supplies) is expected to cause increases smaller than 0.05 percent in overall (area-wide) emissions of nitrogen oxides (NOx). BAsed on the photochemical state of the South Coast Air Basin, any increase in NOx is expected to cause an increase in the highest local ozone concentrations, and this is reflected in model results. However, the magnitude of the increase is well below the generally accepted accuracy of the model and would not be discernible with the existing monitoring network. Modeling of hypothetical scenarios indicates that discernible changes to ambient ozone and particulate matter concentrations would occur only at LNG distribution rates that are not achievable with current or planned infrastructure and with Wobbe index vlaues that exceed current gas quality tariffs. Results of these hypothetical scenarios are presented for consideration of any proposed substantial expansion of LNG supply infrastructure in Southern California.

  6. Modelling hydrothermal venting in volcanic sedimentary basins: Impact on hydrocarbon maturation and paleoclimate

    Science.gov (United States)

    Iyer, Karthik; Schmid, Daniel W.; Planke, Sverre; Millett, John

    2017-06-01

    Vent structures are intimately associated with sill intrusions in sedimentary basins globally and are thought to have been formed contemporaneously due to overpressure generated by gas generation during thermogenic breakdown of kerogen or boiling of water. Methane and other gases generated during this process may have driven catastrophic climate change in the geological past. In this study, we present a 2D FEM/FVM model that accounts for 'explosive' vent formation by fracturing of the host rock based on a case study in the Harstad Basin, offshore Norway. Overpressure generated by gas release during kerogen breakdown in the sill thermal aureole causes fracture formation. Fluid focusing and overpressure migration towards the sill tips results in vent formation after only few tens of years. The size of the vent depends on the region of overpressure accessed by the sill tip. Overpressure migration occurs in self-propagating waves before dissipating at the surface. The amount of methane generated in the system depends on TOC content and also on the type of kerogen present in the host rock. Generated methane moves with the fluids and vents at the surface through a single, large vent structure at the main sill tip matching first-order observations. Violent degassing takes place within the first couple of hundred years and occurs in bursts corresponding to the timing of overpressure waves. The amount of methane vented through a single vent is only a fraction (between 5 and 16%) of the methane generated at depth. Upscaling to the Vøring and Møre Basins, which are a part of the North Atlantic Igneous Province, and using realistic host rock carbon content and kerogen values results in a smaller amount of methane vented than previously estimated for the PETM. Our study, therefore, suggests that the negative carbon isotope excursion (CIE) observed in the fossil record could not have been caused by intrusions within the Vøring and Møre Basins alone and that a contribution

  7. Peak-ring structure and kinematics from a multi-disciplinary study of the Schrödinger impact basin.

    Science.gov (United States)

    Kring, David A; Kramer, Georgiana Y; Collins, Gareth S; Potter, Ross W K; Chandnani, Mitali

    2016-10-20

    The Schrödinger basin on the lunar farside is ∼320 km in diameter and the best-preserved peak-ring basin of its size in the Earth-Moon system. Here we present spectral and photogeologic analyses of data from the Moon Mineralogy Mapper instrument on the Chandrayaan-1 spacecraft and the Lunar Reconnaissance Orbiter Camera (LROC) on the LRO spacecraft, which indicates the peak ring is composed of anorthositic, noritic and troctolitic lithologies that were juxtaposed by several cross-cutting faults during peak-ring formation. Hydrocode simulations indicate the lithologies were uplifted from depths up to 30 km, representing the crust of the lunar farside. Through combining geological and remote-sensing observations with numerical modelling, we show that a Displaced Structural Uplift model is best for peak rings, including that in the K-T Chicxulub impact crater on Earth. These results may help guide sample selection in lunar sample return missions that are being studied for the multi-agency International Space Exploration Coordination Group.

  8. Peak-ring structure and kinematics from a multi-disciplinary study of the Schrödinger impact basin

    Science.gov (United States)

    Kring, David A.; Kramer, Georgiana Y.; Collins, Gareth S.; Potter, Ross W. K.; Chandnani, Mitali

    2016-10-01

    The Schrödinger basin on the lunar farside is ~320 km in diameter and the best-preserved peak-ring basin of its size in the Earth-Moon system. Here we present spectral and photogeologic analyses of data from the Moon Mineralogy Mapper instrument on the Chandrayaan-1 spacecraft and the Lunar Reconnaissance Orbiter Camera (LROC) on the LRO spacecraft, which indicates the peak ring is composed of anorthositic, noritic and troctolitic lithologies that were juxtaposed by several cross-cutting faults during peak-ring formation. Hydrocode simulations indicate the lithologies were uplifted from depths up to 30 km, representing the crust of the lunar farside. Through combining geological and remote-sensing observations with numerical modelling, we show that a Displaced Structural Uplift model is best for peak rings, including that in the K-T Chicxulub impact crater on Earth. These results may help guide sample selection in lunar sample return missions that are being studied for the multi-agency International Space Exploration Coordination Group.

  9. Climate change impacts on irrigated rice and wheat production in Gomti River basin of India: a case study.

    Science.gov (United States)

    Abeysingha, N S; Singh, Man; Islam, Adlul; Sehgal, V K

    2016-01-01

    Potential future impacts of climate change on irrigated rice and wheat production and their evapotranspiration and irrigation requirements in the Gomti River basin were assessed by integrating a widely used hydrological model "Soil and Water Assessment Tool (SWAT)" and climate change scenario generated from MIROC (HiRes) global climate model. SWAT model was calibrated and validated using monthly streamflow data of four spatially distributed gauging stations and district wise wheat and rice yields data for the districts located within the basin. Simulation results showed an increase in mean annual rice yield in the range of 5.5-6.7, 16.6-20.2 and 26-33.4 % during 2020s, 2050s and 2080s, respectively. Similarly, mean annual wheat yield is also likely to increase by 13.9-15.4, 23.6-25.6 and 25.2-27.9 % for the same future time periods. Evapotranspiration for both wheat and rice is projected to increase in the range of 3-9.6 and 7.8-16.3 %, respectively. With increase in rainfall during rice growing season, irrigation water allocation for rice is likely to decrease (<5 %) in future periods, but irrigation water allocation for wheat is likely to increase by 17.0-45.3 % in future periods.

  10. Identification of the Impacts of Climate Changes and Human Activities on Runoff in the Jinsha River Basin, China

    Directory of Open Access Journals (Sweden)

    Xiaowan Liu

    2017-01-01

    Full Text Available Quantifying the impacts of climate changes and human activities on runoff has received extensive attention, especially for the regions with significant elevation difference. The contributions of climate changes and human activities to runoff were analyzed using rainfall-runoff relationship, double mass curve, slope variation, and water balance method during 1961–2010 at the Jinsha River basin, China. Results indicate that runoff at upstream and runoff at midstream are both dominated by climate changes, and the contributions of climate changes to runoff are 63%~72% and 53%~68%, respectively. At downstream, climate changes account for only 13%~18%, and runoff is mainly controlled by human activities, contributing 82%~87%. The availability and stability of results were compared and analyzed in the four methods. Results in slope variation, double mass curve, and water balance method except rainfall-runoff relationship method are of good agreement. And the rainfall-runoff relationship, double mass curve, and slope variation method are all of great stability. The four methods and availability evaluation of them could provide a reference to quantification in the contributions of climate changes and human activities to runoff at similar basins in the future.

  11. Uncertainty in the impacts of projected climate change on the hydrology of a subarctic environment: Liard River Basin

    Directory of Open Access Journals (Sweden)

    R. Thorne

    2010-05-01

    Full Text Available Freshwater inputs from the Mackenzie River into the Arctic Ocean contribute to the control of oceanic dynamics and sea ice cover duration. Half of the annual runoff from the Mackenzie River drains from mountainous regions, where the Liard River, with a drainage area of 275 000 km2, is especially influential. The impact of projected atmospheric warming on the discharge of the Liard River is unclear. Here, uncertainty in climate projections associated with GCM structure (2 °C prescribed warming and magnitude of increases in global mean air temperature (1 to 6 °C on the river discharge are assessed using SLURP, a well-tested hydrological model. Most climate projections indicate (1 warming in this subarctic environment that is greater than the global mean and (2 an increase in precipitation across the basin. These changes lead to an earlier spring freshet (1 to 12 days earlier, a decrease in summer runoff (up to 22% due to enhanced evaporation, and an increase in autumn flow (up to 48%, leading to higher annual discharge and more freshwater input from the Liard River to the Arctic Ocean. All simulations project that the subarctic nival regime will be preserved in the future but the magnitude of changes in river discharge is highly uncertain (ranging from a decrease of 3% to an increase of 15% in annual runoff, due to differences in GCM projections of basin-wide temperature and precipitation.

  12. Max-stable based evaluation of impacts of climate indices on extreme precipitation processes across the Poyang Lake basin, China

    Science.gov (United States)

    Zhang, Qiang; Xiao, Mingzhong; Singh, Vijay P.; Chen, Yongqin David

    2014-11-01

    Monthly precipitation extremes defined by monthly maximum one-day precipitation amount (Rx1day) and maximum consecutive five-day precipitation amount (Rx5day) were analyzed based on daily precipitation data covering a period of 1957 to 2010 across the Poyang Lake basin, the largest freshwater lake basin in the lower Yangtze River basin, China. Based on the max-stable, impacts of El Niño-Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), Indian Ocean Dipole (IOD), Pacific Decadal Oscillation (PDO) on the annual and seasonal Rx1day and Rx5day regimes in the Poyang Lake basin were evaluated. Results indicated that annual Rx1day and Rx5day were influenced mainly by the ENSO events a year earlier and the relations between annual Rx1day and Rx5day and ENSO were statistically positive. However, influences of climate indices on the seasonal Rx1day and Rx5day are complicated when compared with the influences on annual Rx1day and Rx5day regimes. ENSO and PDO can enhance the spring Rx1day regime of the subsequent year and the same year, respectively, but IOD weakens spring Rx1day in the same year. In summer, ENSO can enhance Rx1day of the subsequent year. However, Rx1day in summer had a decreasing tendency. IOD and NAO influenced the autumn Rx1day in another way, i.e., IOD decreases autumn Rx1day of the subsequent year; while NAO enhances autumn Rx1day of the same year. Meanwhile, ENSO can amplify the summer Rx1day in terms of variability, while IOD and NAO can, respectively, influence autumn and winter Rx1day in terms of mean. Influences of climate indices on annual and seasonal Rx5day are similar to those on Rx1day. Results of this study are of great theoretical as well as practical merit in terms of evaluation of droughts and floods under the influences of climate indices.

  13. Sedimentological and geochronological evidences of anthropogenic impacts on river basins in the Northern Latium coastal area (Italy)

    Science.gov (United States)

    Piazzolla, Daniele; Paladini de Mendoza, Francesco; Scanu, Sergio; Marcelli, Marco

    2015-04-01

    In this work we aimed to compare sedimentological and geochronological data from three sediment core samples (MIG50, MRT50, and GRT50) taken in the Northern Latium (Italy) coastal area, at -50 m depth, to data regarding rainfall, river flows and the land use in the three most important hydrographic basins (Mignone, Marta and Fiora) and in the coastal area. Different trends of sediment mass accumulation rate (MAR) are detected in the three cores: a strongly increasing trend was identified in MIG50 and MRT50 cores while GRT50 doesn't show significant variation. Data from the sedimentological analysis of GRT50 core identify a progressive decrease in the sandy component, which declined from about 30% to the current level of 7% over the last 36 years, while MRT50 and MIG50 cores (mainly composed by pelitic fraction > 95%) showed slight variations of textural ratio between silt and clay. According to the general decrease of pluviometric trend observed in Italy, related to teleconnection pattern tendency (NAO), the statistical analysis of rain identified significative decrease only in the Fiora river basin, whereas in the other two locations the decrease was not as significant. Regarding the Fiora river flow, a significative decreasing trend of average flow is detected, while the flood regime remained unaffected over the past 30 years. The analysis of the land use shows that the human activities are increased of 6-10% over the available time steps (1990 - 2006) in Fiora and Mignone river basins, while the Marta river basin has a strong human impact since 1990 highligting more than 80% of artificial soil covering. The largest variation is observed on the Fiora basin (10%) where the antrhopic activities have expanded to an area of about 85 Km2. Moreover, in the last ten years a large beach nourishment in 2004 (570000 m3) and dredging activities in the early second half of 2000s (1000000 m3 moved) were performed in Marina di Tarquinia beach and in front of the Torrevaldaliga

  14. The Impact of Climate Projection Method on the Analysis of Climate Change in Semi-arid Basins

    Science.gov (United States)

    Halper, E.; Shamir, E.

    2016-12-01

    In small basins with arid climates, rainfall characteristics are highly variable and stream flow is tightly coupled with the nuances of rainfall events (e.g. hourly precipitation patterns Climate change assessments in these basins typically employ CMIP5 projections downscaled with Bias Corrected Statistical Downscaling and Bias Correction/Constructed Analogs (BCSD-BCCA) methods, but these products have drawbacks. Specifically, BCSD-BCCA these projections do not explicitly account for localized physical precipitation mechanisms (e.g. monsoon and snowfall) that are essential to many hydrological systems in the U. S. Southwest. An investigation of the impact of different types of precipitation projections for two kinds of hydrologic studies is being conducted under the U.S. Bureau of Reclamation's Science and Technology Grant Program. An innovative modeling framework consisting of a weather generator of likely hourly precipitation scenarios, coupled with rainfall-runoff, river routing and groundwater models, has been developed in the Nogales, Arizona area. This framework can simulate the impact of future climate on municipal water operations. This framework allows the rigorous comparison of the BCSD-BCCA methods with alternative approaches including rainfall output from dynamical downscaled Regional Climate Models (RCM), a stochastic rainfall generator forced by either Global Climate Models (GCM) or RCM, and projections using historical records conditioned on either GCM or RCM. The results will provide guide for the use of climate change projections into hydrologic studies of semi-arid areas. The project extends this comparison to analyses of flood control. Large flows on the Bill Williams River are a concern for the operation of dams along the Lower Colorado River. After adapting the weather generator for this region, we will evaluate the model performance for rainfall and stream flow, with emphasis on statistical features important to the specific needs of flood

  15. Use of System Thinking Software for Determining Climate Change Impacts in Water Balance for the Rio Yaqui Basin, Sonora, Mexico

    Science.gov (United States)

    Tapia, E. M.; Minjarez, J. I.; Espinoza, I. G.; Sosa, C. M.

    2013-05-01

    Climate change in Northwestern Mexico and its hydrological impact on water balance, water scarcity and flooding events, has become a matter of increasing concern over the past several decades due to the region's semiarid conditions. Changes in temperature, precipitation, and sea level will affect agriculture, farming, and aquaculture, in addition to compromising the quality of water resources for human consumption. According to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2007), Global Circulation Models (GCMs) can provide reliable estimations of future climate conditions in addition to atmospheric processes that cause them, based on different input scenarios such as A2 (higher emission of greenhouse gases) and B1 (lower emission of GHG), among others. However, GCM`s resolution results to coarse in regions which have high space and time climate variability. To remediate this, several methods based on dynamical, statistical and empirical analysis have been proposed for downcaling. In this study, we evaluate possible changes in precipitation and temperature for the "Rio Yaqui Basin" in Sonora, Mexico and assess the impact of such changes on runoff, evapotranspiration and aquifer recharge for the 2010-2099 period of time. For this purpose, we analyzed the results of a Bias Corrected and Downscaled Climate Projection from the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset: UKMO-HADCM3 from the Hadley Centre for Climate Prediction. Northwest Mexico is under the influence of the North American Monsoon (NAM), a system affecting the states of Sinaloa and Sonora where the precipitation regimes change drastically during the summer months of June, July and August. It is associated to the sharp variations of topography, precipitation and temperature regimes in the region, so the importance of analyzing the downscaled climate projections. The Rio Yaqui Basin is one of

  16. Impacts of climate change on the seasonality of low flows in 134 catchments in the river Rhine basin using an ensemble of bias-corrected regional climate simulations.

    NARCIS (Netherlands)

    Demirel, M.C.; Booij, M.J.; Hoekstra, A.Y.

    2013-01-01

    The impacts of climate change on the seasonality of low flows were analysed for 134 sub-catchments covering the River Rhine basin upstream of the Dutch-German border. Three seasonality indices for low flows were estimated, namely the seasonality ratio (SR), weighted mean occurrence day (WMOD) and we

  17. Impacts of Near-term Climate Change on Surface Water - Groundwater Availability in the Nueces River basin, TX

    Science.gov (United States)

    Sinha, T.; Kumar, M.

    2014-12-01

    In arid and semi-arid regions, sustainability of surface water and groundwater resources is highly uncertain in the face of climate change as well as under competing demands due to urbanization, population growth and water needs to support ecosystem services. Most studies on climate change impact assessment focus on either surface water or groundwater resources alone. In this study, we utilize a fully coupled surface water and groundwater model, Penn-State Integrated Hydrologic Model (PIHM), and recent climate change projections from Climate Models Inter-comparison Project-5 (CMIP5) to evaluate impacts of near-term climate change on water availability in the Nueces River basin, TX. After performing calibration and validation of PIHM over multiple sites, hindcast simulations will be performed over the 1981-2010 period using data from multiple General Circulation Models (GCMs) obtained from the CMIP5 Project. The results will be compared to the observed data to understand added utility of hindcasts in improving the estimation of surface water and groundwater resources. Finally, we will assess the impacts of climate change on both surface water and groundwater resources over the next 20-30 years, which is a relevant time period for water management decisions.

  18. Possible Impact of climate change on future extreme precipitation of the Oldman, Bow and Red Deer River Basins of Alberta

    Science.gov (United States)

    Yew Gan, Thian; Gizaw, Mesgana

    2016-04-01

    The impact of climate change on extreme precipitation events in the Oldman (ORB), Bow, (BRB) and Red Deer (RRB) River Basins of southern Alberta, Canada, was assessed using six extreme climate indices for the rainy period of May-August (MJJA), and 9-km resolution Special Report on Emission Scenarios (SRES) A2 and A1B climate scenarios of four Coupled Model Intercomparison Project Phase 3 (CMIP3) Global Climate Models (GCMs) dynamically downscaled by a regional climate model, MM5. R95p of the three study sites showed an increase of 4% for the 2050s (2041-2070) and 10% for the 2080s (2071-2100) period, whereas R99p increased by 39% (2050s) and 42% (2080s) which suggest a projected increase in the volume of precipitation expected in future very wet and particularly extremely wet days. Similarly, R20mm, P30yr, RX1day and RX5day are also projected to increase by about 15% by the mid- and late 21st century in the three study sites. However, compared to BRB and RRB, ORB located in the southernmost part of the study site is projected to undergo a relatively higher increase in both temperature and precipitation intensity, which is assessed in terms of indices such as P30yr, RX1day and RX5day. On the other hand, RRB and BRB are projected to experience higher increase in R20mm, which suggest a relatively higher increase in the number of very heavy precipitation days projected for these two basins. Overall, these results suggest that in the 2050s and 2080s, southern Alberta will be expected to experience more frequent and severe intensive storm events in the MJJA season that could potentially increase the risk of future flooding in this region. Ref: Gizaw, M., and Gan, T. Y., 2015, Possible Impact of climate change on future extreme precipitation of the Oldman, Bow and Red Deer River Basins of Alberta, Int. Journal Climatology, DOI:10.1002/joc.4338

  19. The Impact of Ecosystem Functional Type Changes on the La Plata Basin Climate

    Institute of Scientific and Technical Information of China (English)

    Seung-Jae LEE; E.Hugo BERBERY; Domingo ALCARAZ-SEGURA

    2013-01-01

    In this paper,the effects of land cover changes on the climate of the La Plata Basin in southern South America are investigated using the Weather and Research Forecasting (WRF) Model configured on a 30/10-km two-way interactive nested grid.To assess the regional climate changes resulting from land surface changes,the standard land cover types are replaced by time-varying Ecosystem Functional Types (EFTs),which is a newly devised land-cover classification that characterizes the spatial and interannual variability of surface vegetation dynamics.These variations indicate that natural and anthropogenic activities have caused changes in the surface physical parameters of the basin,such as albedo and roughness length,that contributed to regional climate changes.EFTs are obtained from functional attributes of vegetation computed from properties of the Normalized Difference Vegetation Index (NDVI) to represent patches of the land surface with homogeneous energy and gas exchanges with the atmosphere.Four simulations are conducted,each experimental period ranging from September to November in two contrasting years,1988 and 1998.The influence of an identical EFT change on the surface heat fluxes,2-m temperature and humidity,10-m winds,convective instabilities and large-scale moisture fluxes and precipitation are explored for 1988 (a dry year) and 1998 (a wet year).Results show that the surface and atmospheric climate has a larger response to the same EFT changes in a dry year for 2-m temperature and 10-m wind; the response is larger in a wet year for 2-m water vapor mixing ratio,convective available potential energy,vertically integrated moisture fluxes and surface precipitation.For EFTs with high productivity and a weak seasonal cycle,the nearsurface temperature during the spring of 1988 and 1998 increased by as much as 1℃ in the central and western portions of La Plata Basin.Additionally,for higher productivity EFTs,precipitation differences were generally positive in

  20. Spatial Variation of the Impacts of Climate Change and Population Growth on Water Resources in the Apalachicola-Chattahoochee-Flint River Basin

    Science.gov (United States)

    Lownsbery, K.; Steinschneider, S.; Brown, C. M.

    2013-12-01

    Water resource systems around the world are increasingly stressed from climate change and human development, which often results in conflict and highlights the need for appropriate management strategies. One example is the Apalachicola-Chattahoochee-Flint basin in the southeastern US, where decades of legal battles have attempted to apportion the water between metropolitan Atlanta, GA and other stakeholders. This study examines the relative impact of the most significant regional stressors - climate change and population growth, on stakeholder relevant metrics at appropriate time (the next 50 years) and spatial (basin and sub-basin) scales. The system is analyzed within a framework that imposes transient changes and encompasses the range of system response to projected changes. Significant findings are that population growth is the most significant stressor in the upper basin which encompasses the metropolitan Atlanta region. However, climate change, specifically precipitation decrease, is the most significant stressor for the center and Gulf of Mexico portions of the basin. Temperature has little impact because changes in agricultural water use are not considered. Additionally, the metric elasticity to stressor changes is nonlinear.

  1. Study of human occupation impacts in the Batedor river basin in the Mantiqueira mountain in the municipality of Cruzeiro, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo dos Santos Targa

    2008-04-01

    Full Text Available The study of hydrographic basins as territorial units integrating the management of hydric resources is essential to guarantee sustainable use of natural resources in these basins. The establishment of the Paraíba do Sul hydrographic basins committee, in 1994, determined the need for management planning information and integration actions in the Paraíba do Sul basin which incorporates a variety of industries and intense land use. The Batedor river, in the municipality of Cruzeiro, SP, flows into the Passa Vinte which is an affluent of Paraíba do Sul river. Its mouth is located at 22°31’0.63”S and 45°01’2.07”W. Its farthest water contributing source lies about 8.5 km, near the Itaguaré peak 2,308 m high, in the Mantiqueira mountain on the border of São Paulo and Minas Gerais States. To characterize land use in the Batedor hydrographic basin, Landsat imagery and topographic charts were analyzed based on remote sensing and geoprocessing techniques. This paper describes the study of impacts related to land and water resources use in the Batedor river basin and the generation of support material for environmental education. Results has shown that this basin has good water supply, has no flooding risk and has several springs running down the Mantiqueira Moutain slopes that form young creeks with few meanders. Irregular human occupation for housing and subsistence agriculture, mainly banana plantations can be seen in deep slopes and riparian areas, as well as degraded pastures that indicate inappropriate land use and no conformance to pertinent legislation. The decrease in forest vegetation cover can cause severe erosion with significant soil loss and sediment deposition in the river, thus reducing water quality and regulated quantity. This basin is currently responsible for 70% of the water supply for the city of Cruzeiro, SP.

  2. Study of human occupation impacts in the Batedor river basin in the Mantiqueira Mountain in the municipal district of Cruzeiro, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo dos Santos Targa

    2008-04-01

    Full Text Available The study of hydrographic basins as territorial units integrating the management of hydric resources is essential to guarantee sustainable use of natural resources in these basins. The establishment of the Paraíba do Sul hydrographic basins committee, in 1994, determined the need for management planning and action integration in the Paraíba do Sul basin which incorporates a variety of industries and intense land use. The Batedor river, in the municipality of Cruzeiro, SP, flows into the Passa Vinte which is an affluent of Paraíba do Sul river. Its mouth is located at 22°31’0.63”S and 45°01’2.07”W. Its farthest water contributing source lies about 8.5 km, near the Itaguaré peak 2,308 m high, in the Mantiqueira Mountain on the border of São Paulo and Minas Gerais States. To characterize land use in the Batedor hydrographic basin, Landsat imagery and topographic charts were analyzed based on remote sensing and geoprocessing techniques. This paper describes the study of impacts related to land and water resources use in the Batedor river basin and the generation of educational environmental material. Results have shown that this basin has good water supply, has no flooding risk and has several springs running down the Mantiqueira Moutain slopes that form young creeks with few meanders. Irregular human occupation for housing and subsistence agriculture, mainly banana plantations can be seen in deep slopes and riparian areas, as well as degraded pastures that indicate inappropriate land use and no conformance to pertinent legislation. The decrease in forest vegetation cover can cause severe erosion with significant soil loss and sediment deposition in the river, thus reducing water quality and quantity during the dry season. This basin is currently responsible for 70% of the Cruzeiro, SP water supply.

  3. Mercury assessment and evaluation of its impact on fish in the Cecina river basin (Tuscany, Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Scerbo, R. [CNR Istituto di Biofisica, Area della Ricerca Pisa-S. Cataldo, Via G. Moruzzi 1, 56124 Pisa (Italy); Ristori, T. [CNR Istituto di Biofisica, Area della Ricerca Pisa-S. Cataldo, Via G. Moruzzi 1, 56124 Pisa (Italy); Stefanini, B. [CNR Istituto di Biofisica, Area della Ricerca Pisa-S. Cataldo, Via G. Moruzzi 1, 56124 Pisa (Italy); De Ranieri, S. [Dipartimento Scienze Uomo e Ambiente, Universita di Pisa, Via Volta 6, 56100 Pisa (Italy); Barghigiani, C. [CNR Istituto di Biofisica, Area della Ricerca Pisa-S. Cataldo, Via G. Moruzzi 1, 56124 Pisa (Italy)]. E-mail: barghigiani@cibm.it

    2005-05-01

    This paper reports the results of mercury contamination monitoring in the Cecina river basin (Tuscany, Italy). Mercury was measured in the waters, sediments and fish species of the river and its most important tributaries. In fish specimens the organic form was also determined. The results showed high mercury levels in most of the samples analysed. Particularly high concentrations were found in the sediments of the S. Marta canal flowing into the Cecina, where a chlor-alkali plant discharges its wastes, and high levels were still detectable 31 km downstream from the confluence. Near the S. Marta confluence many fish specimens were very contaminated and a study on Leuciscus cephalus cabeda growth suggested that at this site mercury accumulation occurs in these organisms since they are very young. - Mercury entering water from a chlor-alkali plant near Tuscany has led to contamination of river food webs.

  4. Mercury assessment and evaluation of its impact on fish in the Cecina river basin (Tuscany, Italy).

    Science.gov (United States)

    Scerbo, R; Ristori, T; Stefanini, B; De Ranieri, S; Barghigiani, C

    2005-05-01

    This paper reports the results of mercury contamination monitoring in the Cecina river basin (Tuscany, Italy). Mercury was measured in the waters, sediments and fish species of the river and its most important tributaries. In fish specimens the organic form was also determined. The results showed high mercury levels in most of the samples analysed. Particularly high concentrations were found in the sediments of the S. Marta canal flowing into the Cecina, where a chlor-alkali plant discharges its wastes, and high levels were still detectable 31 km downstream from the confluence. Near the S. Marta confluence many fish specimens were very contaminated and a study on Leuciscus cephalus cabeda growth suggested that at this site mercury accumulation occurs in these organisms since they are very young.

  5. Climate change impacts on the Lehman-Baker Creek drainage in the Great Basin National Park

    Science.gov (United States)

    Volk, J. M.

    2013-12-01

    Global climate models (GCMs) forced by increased CO2 emissions forecast anomalously dry and warm trends over the southwestern U.S. for the 21st century. The effect of warmer conditions may result in decreased surface water resources within the Great Basin physiographic region critical for ecology, irrigation and municipal water supply. Here we use downscaled GCM output from the A2 and B1 greenhouse gas emission scenarios to force a Precipitation-Runoff Modeling System (PRMS) watershed model developed for the Lehman and Baker Creeks Drainage (LBCD) in the Great Basin National Park, NV for a century long time period. The goal is to quantify the effects of rising temperature to the water budget in the LBCD at monthly and annual timescales. Dynamically downscaled GCM projections are attained from the NSF EPSCoR Nevada Infrastructure for Climate Change Science, Education, and Outreach project and statistically downscaled output is retrieved from the "U.S. Bias Corrected and Downscaled WCRP CMIP3 Climate Projections". Historical daily climate and streamflow data have been collected simultaneously for periods extending 20 years or longer. Mann-Kendal trend test results showed a statistically significant (α= 0.05) long-term rising trend from 1895 to 2012 in annual and monthly average temperatures for the study area. A grid-based, PRMS watershed model of the LBCD has been created within ArcGIS 10, and physical parameters have been estimated at a spatial resolution of 100m. Simulation results will be available soon. Snow cover is expected to decrease and peak runoff to occur earlier in the spring, resulting in increased runoff, decreased infiltration/recharge, decreased baseflows, and decreased evapo-transpiration.

  6. The impact of climate change on hydrometeorological droughts at a basin scale

    Science.gov (United States)

    Vrochidou, A.-E. K.; Tsanis, I. K.; Grillakis, M. G.; Koutroulis, A. G.

    2013-01-01

    SummaryThree Global Climate Models (GCMs) output (precipitation and temperature), bias corrected with the WATCH Forcing Data (WFD), for the A2 and B1 scenarios, are used for drought assessment at a basin scale. At a first step, the hydrological model IHMS-HBV was calibrated using both local and large scale forcing data (precipitation and temperature) aiming to assess the suitability of large scale forcing data in a small basin, Platis, located in Crete, for the period 1974-1999. The second step includes the forcing of the WFD calibrated HBV model with the bias corrected GCM output from 2001 to 2100 (WATCH Driving Data). The produced hydrological variables, flow, soil moisture and lower groundwater reservoir volume were used for the hydrological regime assessment and drought identification with the aid of the threshold level method. A quantitative comparison with four future sub-periods was carried out addressing the drought events number, duration and deficit volume. Simulations of both emission scenarios indicate a significant decrease in all hydrological parameters. The relative change of drought characteristics for the future periods in terms of the three-model ensemble implied severe drought conditions. For A2 scenario, it was found that the number of drought events could increase up to 98%, 109% and 81% in flow, soil moisture and groundwater respectively. B1 scenario provided more conservative estimates, with an increase of drought events number up to 56%, 92% and 34% in flow, soil moisture and groundwater, respectively. The drought duration difference between scenarios reaches up to 33%, 89% and 34% for simulated flow, soil moisture and groundwater respectively till 2100. Moderate changes can be noticed in drought deficit volume with an estimated maximum increase of 19%, 33% and 22% in flow, soil moisture and groundwater involving A2 scenario, whereas B1 scenario projected 10%, 2% and 26% maximum increase for the former parameters. The evolution of the

  7. The Impact of Levant Basin Oil and Natural Gas Discoveries on Lebanese-Israeli Relations

    Science.gov (United States)

    2014-12-12

    and Natural Gas SWOT Analysis .......................................................... 53 Section 8: Discoveries’ Impact on Relations between...Natural Gas Discoveries in Israel ........................................................34 Table 3. Lebanese Findings using SWOT Analysis ...54 Table 4. Israeli Findings using SWOT Analysis ............................................................56

  8. A new eco-hydrological distributed model for the predictions of the climate change impact on water resources of Mediterranean water-limited basins: the Mulargia basin case study in Sardinia.

    Science.gov (United States)

    Sarigu, Alessio; Montaldo, Nicola

    2017-04-01

    In the last three decades, climate change and human activities increased desertification process in Mediterranean regions, with dramatic consequences for agriculture and water availability. For instance in the main reservoir systems in Sardinia the average annual runoff in the latter part of the 20th century decreased of more than 50% compared with the previous period, while the precipitation over the Sardinia basin has decreased, but not at such a drastic rate as the discharge, with an high precipitation elasticity to streamflow, highlighting the key role of the rainfall seasonality on runoff production. IPCC climate change scenarios predict a further decrease of winter rainfall, which is the key term for runoff production in these typical Mediterranean climate basins, and air temperature increase, which can potentially impact on evapotranspiration, soil moisture and runoff. Only the use of an accurate ecohydrological physically based distributed model allow to well predict the impact of the climate change scenarios on the basin water resources. A new eco-hydrological model is developed that couples a distributed hydrological model of and a vegetation dynamic model (VDM). The hydrological model estimates the soil water balance of each basin cell using the force-restore method, the Philips model for infiltration estimate and the Penman-Monteith equation for evapotranspiration estimate. The VDM evaluates the changes in biomass over time for each cell and provides the leaf area index (LAI), which is then used by the hydrological model for evapotranspiration and rainfall interception estimates. Case study is the Mulargia basin (Sardinia, basin area of about 70 km2), where an extended field campaign started from 2003, with rain and discharge data observed at the basin outlet, periodic field measurements of soil moisture and LAI all over the basin, and evapotraspiration estimates using an eddy correlation based tower. The Mulargia basin case study is a very interesting

  9. Lunar mare deposits associated with the Orientale impact basin: New insights into mineralogy, history, mode of emplacement, and relation to Orientale Basin evolution from Moon Mineralogy Mapper (M3) data from Chandrayaan-1

    Science.gov (United States)

    Whitten, J.; Head, J.W.; Staid, M.; Pieters, C.M.; Mustard, J.; Clark, R.; Nettles, J.; Klima, R.L.; Taylor, L.

    2011-01-01

    Moon Mineralogy Mapper (M3) image and spectral reflectance data are combined to analyze mare basalt units in and adjacent to the Orientale multiring impact basin. Models are assessed for the relationships between basin formation and mare basalt emplacement. Mare basalt emplacement on the western nearside limb began prior to the Orientale event as evidenced by the presence of cryptomaria. The earliest post-Orientale-event mare basalt emplacement occurred in the center of the basin (Mare Orientale) and postdated the formation of the Orientale Basin by about 60-100 Ma. Over the next several hundred million years, basalt patches were emplaced first along the base of the Outer Rook ring (Lacus Veris) and then along the base of the Cordillera ring (Lacus Autumni), with some overlap in ages. The latest basalt patches are as young as some of the youngest basalt deposits on the lunar nearside. M3 data show several previously undetected mare patches on the southwestern margins of the basin interior. Regardless, the previously documented increase in mare abundance from the southwest toward the northeast is still prominent. We attribute this to crustal and lithospheric trends moving from the farside to the nearside, with correspondingly shallower density and thermal barriers to basaltic magma ascent and eruption toward the nearside. The wide range of model ages for Orientale mare deposits (3.70-1.66 Ga) mirrors the range of nearside mare ages, indicating that the small amount of mare fill in Orientale is not due to early cessation of mare emplacement but rather to limited volumes of extrusion for each phase during the entire period of nearside mare basalt volcanism. This suggests that nearside and farside source regions may be similar but that other factors, such as thermal and crustal thickness barriers to magma ascent and eruption, may be determining the abundance of surface deposits on the limbs and farside. The sequence, timing, and elevation of mare basalt deposits

  10. Impact of altitudinal variability on streamflows in mountainous catchments under changing climate (Upper Indus Basin), Himalayas Pakistan

    Science.gov (United States)

    Khan, K. M.; Yaseen, M.

    2014-12-01

    Pakistan's economy is based on agriculture that is highly dependent on water resources originating in the mountain sources of the Upper Indus Basin (UIB). Various rivers i.e. Chitral, Swat, Kabul, Hunza, Gilgit, Astore, Shigar, Shyok & tributaries contribute water to main Indus River. The elevation of UIB ranges from 254 m to 8570 m a.m.s.l. Changes in climate and related hydrological impacts vary in space and time as affected by local climatic and topographic settings. So, the objective of this study was to assess the climate change and related hydrological impacts resulting from altitudinal variability. Trend analyses were performed by applying Mann-Kendall and Sen's method was applied to estimate slope time series that indicates changes in river flows. The results of this study indicate that maximum temperature in annual, winter, spring and autumn seasons has increased with increased in altitude while annual, winter and autumn minimum temperature has decreased with increased in altitude for the period (1961-2011). Moreover, annual, winter, summer and autumn precipitation has been decreased. The impact of altitudinal variability under changing climate yields that annual and seasonal streamflows in River Indus (at Kharmong, Alam Br. and Khairabad), Sawat (at Kalam) and Kabul (at Nowshera) have decreased whereas in River Shoyk (9%), Shigar (7%) and Indus at Kachura (5%) have been increased. However, annual runoff in Gilgit (1%) and Hunza River (18%) has increased by increasing 2 % annual temperature. A seasonal correlation coefficient between temperature and streamflow has the positive correlation in most of the sub-basins of UIB for both spring and summer. With increased 1 oC temperature in spring yields increased streamflow for rives Gilgit, Chitral, Astore, Shoyk, Shigar, Indus at Kachura & Kharmong and Hunza with percentage of 19, 5, 11, 15, 9, 7, 1 and 12 respectively. The prevailing trends and variability, caused by climate change, have an effect on the flows

  11. Potential impacts of climate warming on water supply reliability in the Tuolumne and Merced River Basins, California.

    Science.gov (United States)

    Kiparsky, Michael; Joyce, Brian; Purkey, David; Young, Charles

    2014-01-01

    We present an integrated hydrology/water operations simulation model of the Tuolumne and Merced River Basins, California, using the Water Evaluation and Planning (WEAP) platform. The model represents hydrology as well as water operations, which together influence water supplied for agricultural, urban, and environmental uses. The model is developed for impacts assessment using scenarios for climate change and other drivers of water system behavior. In this paper, we describe the model structure, its representation of historical streamflow, agricultural and urban water demands, and water operations. We describe projected impacts of climate change on hydrology and water supply to the major irrigation districts in the area, using uniform 2 °C, 4 °C, and 6 °C increases applied to climate inputs from the calibration period. Consistent with other studies, we find that the timing of hydrology shifts earlier in the water year in response to temperature warming (5-21 days). The integrated agricultural model responds with increased water demands 2 °C (1.4-2.0%), 4 °C (2.8-3.9%), and 6 °C (4.2-5.8%). In this sensitivity analysis, the combination of altered hydrology and increased demands results in decreased reliability of surface water supplied for agricultural purposes, with modeled quantity-based reliability metrics decreasing from a range of 0.84-0.90 under historical conditions to 0.75-0.79 under 6 °C warming scenario.

  12. Potential impacts of climate warming on water supply reliability in the Tuolumne and Merced River Basins, California.

    Directory of Open Access Journals (Sweden)

    Michael Kiparsky

    Full Text Available We present an integrated hydrology/water operations simulation model of the Tuolumne and Merced River Basins, California, using the Water Evaluation and Planning (WEAP platform. The model represents hydrology as well as water operations, which together influence water supplied for agricultural, urban, and environmental uses. The model is developed for impacts assessment using scenarios for climate change and other drivers of water system behavior. In this paper, we describe the model structure, its representation of historical streamflow, agricultural and urban water demands, and water operations. We describe projected impacts of climate change on hydrology and water supply to the major irrigation districts in the area, using uniform 2 °C, 4 °C, and 6 °C increases applied to climate inputs from the calibration period. Consistent with other studies, we find that the timing of hydrology shifts earlier in the water year in response to temperature warming (5-21 days. The integrated agricultural model responds with increased water demands 2 °C (1.4-2.0%, 4 °C (2.8-3.9%, and 6 °C (4.2-5.8%. In this sensitivity analysis, the combination of altered hydrology and increased demands results in decreased reliability of surface water supplied for agricultural purposes, with modeled quantity-based reliability metrics decreasing from a range of 0.84-0.90 under historical conditions to 0.75-0.79 under 6 °C warming scenario.

  13. Evaluation of the Impacts of Land Use on Water Quality: A Case Study in The Chaohu Lake Basin

    Directory of Open Access Journals (Sweden)

    Juan Huang

    2013-01-01

    Full Text Available It has been widely accepted that there is a close relationship between the land use type and water quality. There have been some researches on this relationship from the perspective of the spatial configuration of land use in recent years. This study aims to analyze the influence of various land use types on the water quality within the Chaohu Lake Basin based on the water quality monitoring data and RS data from 2000 to 2008, with the small watershed as the basic unit of analysis. The results indicated that there was significant negative correlation between forest land and grassland and the water pollution, and the built-up area had negative impacts on the water quality, while the influence of the cultivated land on the water quality was very complex. Besides, the impacts of the landscape diversity on the indicators of water quality within the watershed were also analyzed, the result of which indicated there was a significant negative relationship between them. The results can provide important scientific reference for the local land use optimization and water pollution control and guidance for the formulation of policies to coordinate the exploitation and protection of the water resource.

  14. Evaluation of the impacts of land use on water quality: a case study in the Chaohu Lake Basin.

    Science.gov (United States)

    Huang, Juan; Zhan, Jinyan; Yan, Haiming; Wu, Feng; Deng, Xiangzheng

    2013-01-01

    It has been widely accepted that there is a close relationship between the land use type and water quality. There have been some researches on this relationship from the perspective of the spatial configuration of land use in recent years. This study aims to analyze the influence of various land use types on the water quality within the Chaohu Lake Basin based on the water quality monitoring data and RS data from 2000 to 2008, with the small watershed as the basic unit of analysis. The results indicated that there was significant negative correlation between forest land and grassland and the water pollution, and the built-up area had negative impacts on the water quality, while the influence of the cultivated land on the water quality was very complex. Besides, the impacts of the landscape diversity on the indicators of water quality within the watershed were also analyzed, the result of which indicated there was a significant negative relationship between them. The results can provide important scientific reference for the local land use optimization and water pollution control and guidance for the formulation of policies to coordinate the exploitation and protection of the water resource.

  15. Spatial scale and seasonal dependence of land use impacts on riverine water quality in the Huai River basin, China.

    Science.gov (United States)

    Liu, Jianfeng; Zhang, Xiang; Wu, Bi; Pan, Guoyan; Xu, Jing; Wu, Shaofei

    2017-07-19

    Land use pattern is an effective reflection of anthropic activities, which are primarily responsible for water quality deterioration. A detailed understanding of relationship between water quality and land use is critical for effective land use management to improve water quality. Linear mixed effects and multiple regression models were applied to water quality data collected from 2003 to 2010 from 36 stations in the Huai River basin together with topography and climate data, to characterize the land use impacts on water quality and their spatial scale and seasonal dependence. The results indicated that the influence of land use categories on specific water quality parameter was multiple and varied with spatial scales and seasons. Land use exhibited strongest association with dissolved oxygen (DO) and ammonia nitrogen (NH3-N) concentrations at entire watershed scale and with total phosphorus (TP) and fluoride concentrations at finer scales. However, the spatial scale, at which land use exerted strongest influence on instream chemical oxygen demand (COD) and biochemical oxygen demand (BOD) levels, varied with seasons. In addition, land use composition was responsible for the seasonal pattern observed in contaminant concentrations. COD, NH3-N, and fluoride generally peaked during dry seasons in highly urbanized regions and during rainy seasons in less urbanized regions. High proportion of agricultural and rural areas was associated with high nutrient contamination risk during spring. The results highlight the spatial scale and seasonal dependence of land use impacts on water quality and can provide scientific basis for scale-specific land management and seasonal contamination control.

  16. Climate Change Impacts on Water and Crop Yields in the Glacial Dominated Beas River Basin in India

    Science.gov (United States)

    Holman, I.; Remesan, R.; Ojha, C. S. P. S.; Adeloye, A. J.

    2014-12-01

    Himalayan valleys are confronting severe climate change related issues (floods in summer, flash flood and landslides, water scarcity in higher altitudes) because of fluctuating monsoon precipitation and increasing seasonal temperatures. In this study, the Soil and Water Assessment Tool (SWAT) model is applied to the River Beas basin, using daily Tropical Rainfall Measuring Mission (TRMM) precipitation and NCEP Climate Forecast System Reanalysis (CFSR) meteorological data to simulate the river regime and crop yields. The Beas is regionally significant as it holds two giant dams, one which annually diverts 4700 Mm3 of water to a nearby basin. We have applied Sequential Uncertainty Fitting Ver. 2 (SUFI-2) to quantify the parameter uncertainty of the stream flow modelling. The model evaluation statistics for Daily River flows at the Jwalamukhi and Pong gauges show good agreement with measured flows (Nash Sutcliffe efficiency of 0.70 and PBIAS of 7.54 %). We then applied the models within a scenario-neutral framework to develop hydrological and crop yield Impact Response Surfaces (IRS) for future changes in annual temperature and precipitation for the region from AR5. Future Q10 and Q90 daily flows indicate amplified 'flash flood' situations and increased low flows, respectively, with increasing temperatures due to increased snowmelt from retreating glaciers. Under existing crop and irrigation management practices, the IRS show decreasing and increasing crop yields for summer (monsoon) and winter (post monsoon) crops, respectively, with rising temperature. Climate change scenario studies shows that, the sensitivity of winter (post monsoon) crop yields to precipitation increases with increasing temperature. The paper will consider the implications of the research for future agricultural water resource management and the potential of adaptation to offset yield losses

  17. Nonstationarity in the occurrence rate of floods in the Tarim River basin, China, and related impacts of climate indices

    Science.gov (United States)

    Gu, Xihui; Zhang, Qiang; Singh, Vijay P.; Chen, Xi; Liu, Lin

    2016-07-01

    Amplification of floods in the Xinjiang, China, has been observed, but reports on their changing properties and underlying mechanisms are not available. In this study, occurrence rates of floods in the Tarim River basin, the largest inland arid river basin in China, were analyzed using the Kernel density estimation technique and bootstrap resampling method. Also analyzed were the occurrence rates of precipitation extremes using the POT (Peak over Threshold)-based sampling method. Both stationary and non-stationary models were developed using GAMLSS (Generalized Additive Models for Location, Scale and Shape) to model flood frequency with time, climate index, precipitation and temperature as major predictors. Results indicated: (1) two periods with increasing occurrence of floods, i.e., the late 1960s and the late 1990s with considerable fluctuations around 2-3 flood events during time intervals between the late 1960s and the late 1990s; (2) changes in the occurrence rates of floods were subject to nonstationarity. A persistent increase of flood frequency and magnitude was observed during the 1990s and reached a peak value; (3) AMO (Atlantic Multidecadal Oscillation) and AO (Atlantic Oscillation) in winter were the key influencing climate indices impacting the occurrence rates of floods. However, NAO (North Atlantic Oscillation) and SOI (South Oscillation Index) are two principle factors that influence the occurrence rates of regional floods. The AIC (Akaike Information Criterion) values indicated that compared to the influence of climate indices, occurrence rates of floods seemed to be more sensitive to temperature and precipitation changes. Results of this study are important for flood management and development of mitigation measures.

  18. Antipodal terrains created by the Rheasilvia basin forming impact on asteroid 4 Vesta

    Science.gov (United States)

    Bowling, T. J.; Johnson, B. C.; Melosh, H. J.; Ivanov, B. A.; O'Brien, D. P.; Gaskell, R.; Marchi, S.

    2013-09-01

    Rheasilvia impact on asteroid 4 Vesta may have been sufficiently large to create disrupted terrains at the impact antipode. This paper investigates the amount of deformation expected at the Rheasilvia antipode using numerical models of sufficient resolution to directly observe terrain modification and material displacements following the arrival of impact stresses. We find that the magnitude and mode of deformation expected at the impact antipode is strongly dependent on both the sound speed and porosity of Vesta's mantle, as well as the strength of the Vestan core. In the case of low mantle porosities and high core strengths, we predict the existence of a topographic high (a peak) caused by the collection of spalled and uplifted material at the antipode. Observations by NASA's Dawn spacecraft cannot provide definite evidence that large amounts of deformation occurred at the Rheasilvia antipode, largely due to the presence of younger large impact craters in the region. However, a deficiency of small craters near the antipodal point suggests that some degree of deformation did occur.

  19. Impacts of Overgrazing and Reclamation on Soil Resources in Rangeland Ecosystems in Huailai Basin, Hebei, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong; HE Wei-ming; JIANG Shi-zhong

    2005-01-01

    The soil constituents and relations between the variation of soil resources and plant communities in three adjacent sites representing the overgrazing, reclamation and comparatively undisturbed communities respectively were quantified and examined in study area in Huailai Basin, Hebei Province, China. There have been significantly greater constituent of C, N, P in the soils of shrubland site. Corg, Ntotal, Navail and Pavail were between 1.18 and 3.90 times more concentrated in the soils of shrubland site in comparison with the other two sites. Although the Ptotal concentration was lower in shrubland soils than in overgrazed rangeland soils, the Pavail concentration, however, was significantly greater in the soils of shrubland site, and increased by 59.1% and even 289.6% in the soils of shrubland site comparing to those in the soils of rangeland and millet field sites. Among the three sites, CV exceeding 40% were found for SO4, Cl, and F ion. The CV of organic carbon also exceeded 40% but only in the soils of millet field site. The highest CV were found for F, SO4 ion in the soils of shrubland and overgrazed rangeland sites, while for Cl and SO4ion in those of millet field site. The results also showed that the introductions of shrubs are of vital importance for the accumulation of soil nutrients and maintenance of soil fertilities, and also for the restoration and reconstruction of desertified ecosystems.

  20. THE IMPACT OF HUMAN ACTIVITIES ON GROUNDWATER RESOURCES IN THE SOUTH EDGE OF TARIM BASIN, XINJIANG

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the modern times, the population growth, development of industrial and agricultural production andthe petroleum exploitation, brought about the unceasing expansion of artificial oasis and abrupt increase of water demand.The artificial hydraulic irrigation engineering took the place of the natural river system, the reservoirs took the place ofnatural lakes, which in turn enhanced the space-time redistribution of surface water based on the natural evolution, andso did groundwater. The groundwater recharge reduced 26.2% in 46 years from 1950 to 1995 in the southern piedmontflood plain of Tarim Basin due to mean yearly population increase rate of 27.7%0 and associated with the water use rateincreasing from 24. 6% to 58.4%. At the same time the artificial water system seepage give primary play to groundwaterrecharge, which is up to 57.6% whilst that of the natural system reduce to 33.7%. As a result, groundwater level drop3 -5m widespread except some irrigation area and surroundings of plain reservoir. Spring water discharge also reduceabout 37.6% and discharge zone continuously move away to the north with the value of 0. 5 - 1.2km in the past 40years.

  1. High Chromium Tolerant Bacterial Strains from Palar River Basin: Impact of Tannery Pollution

    Directory of Open Access Journals (Sweden)

    K. Sundar

    2010-04-01

    Full Text Available The basic survey study on tanneries and its pollution in the Palar river basin of Vellore District showed that it has been contaminated with heavy metals especially chromium and salts. This study is to improve our understanding to find the Cr contamination level and the ecology of heavy metal tolerance of the native bacterial flora of our study area. Chromium tolerant strains were isolated from contaminated sediments, water and effluents of various tanneries. The minimum and maximum concentration of chromium sediments was in the range of 47.4 and 682.4 mg/L, with an average of 306.285 mg/L in the study area. Sixty-eight chromium resistant bacterial strains were isolated and Maximum Tolerance Concentration (MTC studies have indicated that the tolerance concentrations of the isolates were in the range of 100-3300 mg/L. These bacterial isolates were also checked for their resistance to other heavy metals like Ni, Pb, Zn, Fe and Cd. Eighty percent of the isolates showed resistance to Ni, Pb, Zn, Fe at 100 ppm level and 45% had shown resistance to Cd. The isolates also had shown tolerance to salt (NaCl up to 9%. Significant note was found in the concentration of chromium and in the chromium tolerance ability of the bacteria in the study area and these chromium tolerance bacteria can be used as the indicator for the Cr contamination.

  2. Impact of potash mining in streams: the Llobregat basin (northeast Spain as a case study

    Directory of Open Access Journals (Sweden)

    Ruben Ladrera

    2016-12-01

    Full Text Available Potash mining is significantly increasing the salt concentration of rivers and streams due to lixiviates coming from the mine tailings. In the present study, we have focused on the middle Llobregat basin (northeast Spain, where an important potash mining activity exists from the beginning of the XX century. Up to 50 million tonnes of saline waste have been disposed in the area, mainly composed of sodium chloride. We assessed the ecological status of streams adjacent to the mines by studying different physicochemical and hydromorphological variables, as well as aquatic macroinvertebrates. We found extraordinary high values of salinity in the studied streams, reaching conductivities up to 132.4 mS/cm. Salt-polluted streams were characterized by a deterioration of the riparian vegetation and the fluvial habitat. Both macroinvertebrate richness and abundance decreased with increasing salinity. In the most polluted stream only two families of macroinvertebrates were found: Ephydridae and Ceratopogonidae. According to the biotic indices IBMWP and IMMi-T, none of the sites met the requirements of the Water Framework Directive (WFD; i.e., good ecological status. Overall, we can conclude that potash-mining activities have the potential to cause severe ecological damage to their surrounding streams. This is mainly related to an inadequate management of the mine tailings, leading to highly saline runoff and percolates entering surface waters. Thus, we urge water managers and policy makers to take action to prevent, detect and remediate salt pollution of rivers and streams in potash mining areas.

  3. Managing the Cumulative Impacts of Land Uses in the Western Canadian Sedimentary Basin: A Modeling Approach

    Directory of Open Access Journals (Sweden)

    Richard, R. Schneider

    2003-07-01

    Full Text Available This case study from northeastern Alberta, Canada, demonstrates a fundamentally different approach to forest management in which stakeholders balance conservation and economic objectives by weighing current management options from the point of view of their long-term effects on the forest. ALCES®, a landscape-scale simulation model, is used to quantify the effects of the current regulatory framework and typical industrial practices on a suite of ecological and economic indicators over the next 100 yr. These simulations suggest that, if current practices continue, the combined activities of the energy and forestry industries in our 59,000 km2 study area will cause the density of edge of human origin to increase from 1.8 km/km 2 to a maximum of 8.0 km/km2. We also predict that older age classes of merchantable forest stands will be largely eliminated from the landscape, habitat availability for woodland caribou will decline from 43 to 6%, and there will be a progressive shortfall in the supply of softwood timber beginning in approximately 60 yr. Additional simulations involving a suite of "best practices" demonstrate that substantial improvements in ecological outcome measures could be achieved through alternative management scenarios while still maintaining a sustainable flow of economic benefits. We discuss the merits of our proposed approach to land use planning and apply it to the Western Canadian Sedimentary Basin.

  4. Tritium clouds environmental impact in air into the Western Mediterranean Basin evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Castro, P., E-mail: paloma.castro@ciemat.es [EURATOM-CIEMAT Association, LNF Fusion National Laboratory, BBTU, Avda Complutense,40 28040 Madrid (Spain); Velarde, M. [ETSII Nuclear Fusion Institute: DENIM, Madrid (Spain); Ardao, J. [AEMET, Environmental Applications Service, 28040 Madrid (Spain); Perlado, J.M. [ETSII Nuclear Fusion Institute: DENIM, Madrid (Spain); Sedano, L. [EURATOM-CIEMAT Association, LNF Fusion National Laboratory, BBTU, Avda Complutense,40 28040 Madrid (Spain)

    2012-08-15

    The paper considers short-term releases of tritium (mainly but not only tritium hydride (HT)) to the atmosphere from a potential ITER-like fusion reactor located in the Mediterranean Basin and explores if the short range legal exposure limits are exceeded (both locally and downwind). For this, a coupled Lagrangian ECMWF/FLEXPART model has been used to follow real time releases of tritium. This tool was analyzed for nominal tritium operational conditions under selected incidental conditions to determine resultant local and Western Mediterranean effects, together with hourly observations of wind, to provide a short-range approximation of tritium cloud behavior. Since our results cannot be compared with radiological station measurements of tritium in air, we use the NORMTRI Gaussian model. We demonstrate an overestimation of the sequence of tritium concentrations in the atmosphere, close to the reactor, estimated with this model when compared with ECMWF/FLEXPART results. A Gaussian 'mesoscale' qualification tool has been used to validate the ECMWF/FLEXPART for winter 2010/spring 2011 with a database of the HT plumes. It is considered that NORMTRI allows evaluation of tritium-in-air-plume patterns and its contribution to doses.

  5. Plausible impact of global climate change on water resources in the Tarim River Basin

    Institute of Scientific and Technical Information of China (English)

    CHEN; Yaning; XU; Zongxue

    2005-01-01

    Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

  6. Combined land use and climate change impact on Surface and Ground water resources in the Rio Cobre and Great River basin, Jamaica

    Science.gov (United States)

    Setegn, S. G.; Melesse, A. M.; Grey, O.; Webber, D.

    2011-12-01

    Possible adverse impacts of land use and climate change on one hand and population pressure, extended droughts, and environmental degradation on the other hand are major factors limiting water resources availability in the watersheds of Jamaica. The main objective of this study is to analyze the combined impact of land use/ land cover changes as well as climate change on the hydrological processes and water recourses availability in the Rio Cobre and Great River basins. A spatially distributed model SWAT was calibrated and validated in the basin and used for the study of land use and climate change impacts in the watersheds. Different land cover types were tested to analyze its impact on the hydrology of the watershed. The main land cover parameters considered within the Great and Rio Cobre River Watershed includes Agriculture, Tourism, Water, Road Infrastructure, Population, Forestry and land cover Information. The outputs of different Global climate model (GCM) were downscaled to the watershed level and used for assessing the impact of climate change on water resources availability in the area. The analysis of climate change impact on the surface and ground water resources of the basin indicated that the basin will experience a change in water balance due to changes in the major climate variables in the forthcoming decades. The direction of streamflow change follows mainly the direction of changes in rainfall. Many of the models show statistically-significant declines in mean annual streamflow (up to 60% reduction in streamflow) for the different time-periods and scenarios. The combined effect of climate and land-use/land-cover change on the hydrological processes and water recourses variability is an important step to develop sustainable adaptation strategy.

  7. The impact of land abandonment on species richness and abundance in the Mediterranean Basin

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Hui, Cang; Gaertner, Mirijam;

    2014-01-01

    the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After...... identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size = 0.2109, P,0...... management at these scales can have a powerful impact on biodiversity. ...

  8. Spatio-temporal Analysis on the Combined Impact of Long-term Climate and Landuse Changes on Blue and Green Water Dynamics over the Ohio River Basin

    Science.gov (United States)

    Du, L.; Rajib, M. A.; Merwade, V.

    2015-12-01

    Impacts of climate and landuse change on the overall water availability can be analytically comprehended in terms of long-term trends in surface and subsurface hydrologic fluxes. The surface and subsurface fluxes can be represented in terms of blue water (BW; surface runoff and deep aquifer recharge) and green water (GW; soil water content and actual evapotranspiration). The objective of this study is to present a comprehensive assessment of the spatial and temporal trend of BW and GW under the historical climate and landuse data over the period of 1935 to 2014 in the Ohio River Basin (490,000 km2), and thereby, quantify the relative effects of climate and landuse changes on their long-term dynamics. The Soil and Water Assessment Tool (SWAT) is used to simulate hydrologic fluxes for the Ohio River Basin by first changing both climate and landuse inputs, and then by only changing the climate input keeping landuse constant. The Mann-Kendall and Theil-Sen trend analyses over the whole basin show volumetric increase in both BW and GW. However, the trends reveal a regional pattern, where GW has increased significantly in the upper and lower parts of the basin in response to prominent landuse change. Whereas, BW has increased significantly only in the lower part that can be related to the significant change in precipitation there. The finding that BW is more affected by precipitation while landuse change is more influential in changing GW, is further supported from the BW and GW trend analyses at the individual sub-basin scale. The results from this study help to understand the collective influence of natural and anthropogenic impacts on hydrologic responses in the Ohio River basin, and thereby provide useful information for future water security and planning.

  9. Where artisanal mines and forest meet: Socio-economic and environmental impacts in the Congo Basin

    NARCIS (Netherlands)

    Ingram, V.J.; Tieguhong, J.C.; Schure, J.M.; Nkamgnia, E.; Tadjuidje, M.H.

    2011-01-01

    While mineral exploitation can provide significant income and employment, it may negatively impact the environment, being ultimately detrimental to livelihoods in the long term. The consequences of mining are of concern in high value forest ecosystems such as the Sangha Tri-National (TNS) landscape

  10. Where artisanal mines and forest meet: socio-economic and environmental impacts in the Congo Basin

    NARCIS (Netherlands)

    Ingram, V.; Tieguhong, J.C.; Schure, J.; Nkamgnia, E.; Tadjuidje, M.H.

    2011-01-01

    While mineral exploitation can provide significant income and employment, it may negatively impact the environment, being ultimately detrimental to livelihoods in the long term. The consequences of mining are of concern in high value forest ecosystems such as the Sangha Tri-National (TNS) landscape

  11. Crustal fluid and ash alteration impacts on the biosphere of Shikoku Basin sediments, Nankai Trough, Japan.

    Science.gov (United States)

    Torres, M E; Cox, T; Hong, W-L; McManus, J; Sample, J C; Destrigneville, C; Gan, H M; Gan, H Y; Moreau, J W

    2015-11-01

    We present data from sediment cores collected from IODP Site C0012 in the Shikoku Basin. Our site lies at the Nankai Trough, just prior to subduction of the 19 Ma Philippine Sea plate. Our data indicate that the sedimentary package is undergoing multiple routes of electron transport and that these differing pathways for oxidant supply generate a complex array of metabolic routes and microbial communities involved in carbon cycling. Numerical simulations matched to pore water data document that Ca(2+) and Cl(1-) are largely supplied via diffusion from a high-salinity (44.5 psu) basement fluid, which supports the presence of halophile Archean communities within the deep sedimentary package that are not observed in shallow sediments. Sulfate supply from basement supports anaerobic oxidation of methane (AOM) at a rate of ~0.2 pmol cm(-3) day(-1) at ~400 mbsf. We also note the disappearance of δ-Proteobacteria at 434 mbsf, coincident with the maximum in methane concentration, and their reappearance at 463 mbsf, coinciding with the observed deeper increase in sulfate concentration toward the basement. We did not, however, find ANME representatives in any of the samples analyzed (from 340 to 463 mbsf). The lack of ANME may be due to an overshadowing effect from the more dominant archaeal phylotypes or may indicate involvement of unknown groups of archaea in AOM (i.e., unclassified Euryarchaeota). In addition to the supply of sulfate from a basement aquifer, the deep biosphere at this site is also influenced by an elevated supply of reactive iron (up to 143 μmol g(-1)) and manganese (up to 20 μmol g(-1)). The effect of these metal oxides on the sulfur cycle is inferred from an accompanying sulfur isotope fractionation much smaller than expected from traditional sulfate-reducing pathways. The detection of the manganese- and iron-reducer γ-Proteobacteria Alteromonas at 367 mbsf is consistent with these geochemical inferences.

  12. High Performance Computing-based Assessment of the Impacts of Climate Change on the Santa Cruz and San Pedro River Basin at Very High Resolution

    Science.gov (United States)

    Robles-Morua, A.; Vivoni, E. R.; Rivera-Fernandez, E. R.; Dominguez, F.; Meixner, T.

    2012-12-01

    Assessing the impact of climate change on large river basins in the southwestern United States is important given the natural water scarcity in the region. The bimodal distribution of annual precipitation also presents a challenge as differential climate impacts during the winter and summer seasons are not currently well understood. In this work, we focus on the hydrological consequences of climate change in the Santa Cruz and San Pedro river basins along the Arizona-Sonora border at high spatiotemporal resolutions (~100 m and ~1 hour). These river systems support rich ecological communities along riparian corridors that provide habitat to migratory birds and support recreational and economic activities. Determining the climate impacts on riparian communities involves assessing how river flows and groundwater recharge will change with altered temperature and precipitation regimes. In this study, we use a distributed hydrologic model, known as the TIN-based Real-time Integrated Basin Simulator (tRIBS), to generate simulated hydrological fields under historical (1991-2000) and climate change (2031-2040) scenarios obtained from an application of the Weather Research and Forecast (WRF) model. Using the distributed model, we transform the meteorological scenarios from WRF at 10-km, hourly resolution into predictions of the annual water budget, seasonal land surface fluxes and individual hydrographs of flood and recharge events. For this contribution, we selected two full years in the historical period and in the future scenario that represent wet and dry conditions for each decade. Given the size of the two basins, we rely on a high performance computing platform and a parallel domain discretization using sub-basin partitioning with higher resolutions maintained at experimental catchments in each river basin. Model simulations utilize best-available data across the Arizona-Sonora border on topography, land cover and soils obtained from analysis of remotely

  13. Impact of the intercontinental transport of biomass burning pollutants on the Mediterranean Basin during the CHARMEX-GLAM airborne campaign

    Science.gov (United States)

    Brocchi, Vanessa; Krysztofiak, Gisèle; Catoire, Valéry; Zbinden, Régina; Guth, Jonathan; El Amraoui, Laaziz; Piguet, Bruno; Dulac, François; Hamonou, Eric; Ricaud, Philippe

    2017-04-01

    The Mediterranean Basin (MB) is at the crossroad of pollutant emissions from Western and Central Europe and of major dust sources from Sahara and Arabian deserts and thus sensitive to climate change and air quality. Several studies (Formenti et al.,J. Geophys. Res., 2002; Ancellet et al., Atmos. Chem. Phys., 2016) also show the impact on the MB of long-range transport of polluted air masses. However, most of the studies have been dedicated to biomass burning aerosols. The aim of the present study is to show trace gases impact on the MB coming from long-range transport of biomass burning. The Gradient in Longitude of Atmospheric constituents above the Mediterranean basin (GLAM) campaign in August 2014, as part of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx) project, aimed at studying the tropospheric chemical variability of gaseous pollutants and aerosols along a West-East transect above the MB. During the GLAM campaign, several instruments onboard the Falcon-20 aircraft (SAFIRE, INSU / Météo-France) were deployed including an infrared laser spectrometer (SPIRIT, LPC2E) able to detect weak variations in the concentration of pollutants. During two flights on 6 and 10 August, increases in CO, O3 and aerosols were measured over Sardinia at 5000 and 9000 m asl, respectively. To assess the origin of the air masses, 20-day backward trajectories with a nested-grid regional scale Lagrangian particle dispersion model (FLEXPART, Stohl et al., Atmos. Chem. Phys., 2005) were calculated. Combined with emissions coming from the Global Fire Assimilation System (GFAS) inventory (Kaiser et al., Biogeosciences, 2012), this leads to CO biomass burning contribution to aircraft measured values. Biomass burning emissions located in Siberia in the first case and in northern America in the second case were identified as the cause of this burden of pollutants in the mid and upper troposphere over the MB. By adjusting the injection height of the model and amplifying emissions

  14. Basin-Scale Leakage Risks from Geologic Carbon Sequestration: Impact on Carbon Capture and Storage Energy Market Competitiveness

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Catherine; Fitts, Jeffrey; Wilson, Elizabeth; Pollak, Melisa; Bielicki, Jeffrey; Bhatt, Vatsal

    2013-03-13

    This three-year project, performed by Princeton University in partnership with the University of Minnesota and Brookhaven National Laboratory, examined geologic carbon sequestration in regard to CO{sub 2} leakage and potential subsurface liabilities. The research resulted in basin-scale analyses of CO{sub 2} and brine leakage in light of uncertainties in the characteristics of leakage processes, and generated frameworks to monetize the risks of leakage interference with competing subsurface resources. The geographic focus was the Michigan sedimentary basin, for which a 3D topographical model was constructed to represent the hydrostratigraphy. Specifically for Ottawa County, a statistical analysis of the hydraulic properties of underlying sedimentary formations was conducted. For plausible scenarios of injection into the Mt. Simon sandstone, leakage rates were estimated and fluxes into shallow drinking-water aquifers were found to be less than natural analogs of CO{sub 2} fluxes. We developed the Leakage Impact Valuation (LIV) model in which we identified stakeholders and estimated costs associated with leakage events. It was found that costs could be incurred even in the absence of legal action or other subsurface interference because there are substantial costs of finding and fixing the leak and from injection interruption. We developed a model framework called RISCS, which can be used to predict monetized risk of interference with subsurface resources by combining basin-scale leakage predictions with the LIV method. The project has also developed a cost calculator called the Economic and Policy Drivers Module (EPDM), which comprehensively calculates the costs of carbon sequestration and leakage, and can be used to examine major drivers for subsurface leakage liabilities in relation to specific injection scenarios and leakage events. Finally, we examined the competiveness of CCS in the energy market. This analysis, though qualitative, shows that financial

  15. Evaluating the impacts of climate and land-use change on the hydrology and nutrient yield in a transboundary river basin: A case study in the 3S River Basin (Sekong, Sesan, and Srepok).

    Science.gov (United States)

    Trang, Nguyen Thi Thuy; Shrestha, Sangam; Shrestha, Manish; Datta, Avishek; Kawasaki, Akiyuki

    2017-01-15

    Assessment of the climate and land-use change impacts on the hydrology and water quality of a river basin is important for the development and management of water resources in the future. The objective of this study was to examine the impact of climate and land-use change on the hydrological regime and nutrient yield from the 3S River Basin (Sekong, Srepok, and Sesan) into the 3S River system in Southeast Asia. The 3S Rivers are important tributaries of the Lower Mekong River, accounting for 16% of its annual flow. This transboundary basin supports the livelihoods of nearly 3.5 million people in the countries of Laos, Vietnam, and Cambodia. To reach a better understanding of the process and fate of pollution (nutrient yield) as well as the hydrological regime, the Soil and Water Assessment Tool (SWAT) was used to simulate water quality and discharge in the 3S River Basin. Future scenarios were developed for three future periods: 2030s (2015-2039), 2060s (2045-2069), and 2090s (2075-2099), using an ensemble of five GCMs (General Circulation Model) simulations: (HadGEM2-AO, CanESM2, IPSL-CM5A-LR, CNRM-CM5, and MPI-ESM-MR), driven by the climate projection for RCPs (Representative Concentration Pathways): RCP4.5 (medium emission) and RCP8.5 (high emission) scenarios, and two land-use change scenarios. The results indicated that the climate in the study area would generally become warmer and wetter under both emission scenarios. Discharge and nutrient yield is predicted to increase in the wet season and decrease in the dry. Overall, the annual discharge and nutrient yield is projected to increase throughout the twenty-first century, suggesting sensitivity in the 3S River Basin to climate and land-use change. The results of this study can assist water resources managers and planners in developing water management strategies for uncertain climate change scenarios in the 3S River Basin. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    Science.gov (United States)

    Zang, C.; Liu, J.; Jiang, L.; Gerten, D.

    2013-07-01

    Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration) and blue water (discharge accumulated in the river network) remain less well understood. We study the spatial patterns of blue and green water flows and the impacts on them of human activities and climate variability as simulated by the Soil and Water Assessment Tool (SWAT) for an inland Heihe river basin located in Northwest China. The results show that total green and blue water flow increased from 1980 to 2005, mainly as a result of climate variability (upward precipitation trends). Direct human activities did not significantly change the total green and blue water flow. However, land use change led to a transformation of 206 million m3 from green to blue water flow, while farmland irrigation expansion resulted in a transformation of 66 million m3 from blue to green water flow. The synchronous climate variability caused an increase of green water flow by 469 million m3 and an increase of blue water flow by 146 million m3 at the river basin level, while the geographical distribution showed an uneven change even with reductions of water flows in western sub-basins at midstream. The results are helpful to benchmark the water resources in the context of global change in the inland river basins in China. This study also provides a general approach to investigate the impacts of historical human activities and climate variability on green and blue water flows at the river basin level.

  17. Impacts of human activities and climate variability on green and blue water flows in the Heihe River Basin in Northwest China

    Directory of Open Access Journals (Sweden)

    C. Zang

    2013-07-01

    Full Text Available Human activities and climate factors both affect the availability of water resources and the sustainability of water management. Especially in already dry regions, water has become more and more scarce with increasing requirements from growing population, economic development and diet shifts. Although progress has been made in understanding variability of runoff, the impacts of climate variability and human activities on flows of both green water (actual evapotranspiration and blue water (discharge accumulated in the river network remain less well understood. We study the spatial patterns of blue and green water flows and the impacts on them of human activities and climate variability as simulated by the Soil and Water Assessment Tool (SWAT for an inland Heihe river basin located in Northwest China. The results show that total green and blue water flow increased from 1980 to 2005, mainly as a result of climate variability (upward precipitation trends. Direct human activities did not significantly change the total green and blue water flow. However, land use change led to a transformation of 206 million m3 from green to blue water flow, while farmland irrigation expansion resulted in a transformation of 66 million m3 from blue to green water flow. The synchronous climate variability caused an increase of green water flow by 469 million m3 and an increase of blue water flow by 146 million m3 at the river basin level, while the geographical distribution showed an uneven change even with reductions of water flows in western sub-basins at midstream. The results are helpful to benchmark the water resources in the context of global change in the inland river basins in China. This study also provides a general approach to investigate the impacts of historical human activities and climate variability on green and blue water flows at the river basin level.

  18. Future Water Management in the South Platte River Basin: Impacts of Hydraulic Fracturing, Population, Agriculture, and Climate Change in a Semi-Arid Region.

    Science.gov (United States)

    Walker, E. L.; Hogue, T. S.; Anderson, A. M.; Read, L.

    2015-12-01

    In semi-arid basins across the world, the gap between water supply and demand is growing due to climate change, population growth, and shifts in agriculture and unconventional energy development. Water conservation efforts among residential and industrial water users, recycling and reuse techniques and innovative regulatory frameworks for water management strive to mitigate this gap, however, the extent of these strategies are often difficult to quantify and not included in modeling water allocations. Decision support systems (DSS) are purposeful for supporting water managers in making informed decisions when competing demands create the need to optimize water allocation between sectors. One region of particular interest is the semi-arid region of the South Platte River basin in northeastern Colorado, where anthropogenic and climatic effects are expected to increase the gap between water supply and demand in the near future. Specifically, water use in the South Platte is impacted by several high-intensity activities, including unconventional energy development, i.e. hydraulic fracturing, and large withdrawals for agriculture; these demands are in addition to a projected population increase of 100% by 2050. The current work describes the development of a DSS for the South Platte River basin, using the Water Evaluation and Planning system software (WEAP) to explore scenarios of how variation in future water use in the energy, agriculture, and municipal sectors will impact water allocation decisions. Detailed data collected on oil and gas water use in the Niobrara shale play will be utilized to predict future sector use. We also employ downscaled climate projections for the region to quantify the potential range of water availability in the basin under each scenario, and observe whether or not, and to what extent, climate may impact management decisions at the basin level.

  19. The impact of climate change on water provision under a low flow regime: a case study of the ecosystems services in the Francoli river basin.

    Science.gov (United States)

    Marquès, Montse; Bangash, Rubab Fatima; Kumar, Vikas; Sharp, Richard; Schuhmacher, Marta

    2013-12-15

    Mediterranean basin is considered one of the most vulnerable regions of the world to climate change and with high probability to face acute water scarcity problem in the coming years. Francolí River basin (NE Spain), located in this vulnerable region is selected as a case study to evaluate the impact of climate change on the delivery of water considering the IPCC scenarios A2 and B1 for the time spans 2011-2040, 2041-2070 and 2071-2100. InVEST model is applied in a low flow river as a new case study, which reported successful results after its model validation. The studied hydrological ecosystem services will be highly impacted by climate change at Francolí River basin. Water yield is expected to be reduced between 11.5 and 44% while total drinking water provisioning will decrease between 13 and 50% having adverse consequences on the water quality of the river. Focusing at regional scale, Prades Mountains and Brugent Tributary provide most of the provision of water and also considered highly vulnerable areas to climate change. However, the most vulnerable part is the northern area which has the lowest provision of water. Francolí River basin is likely to experience desertification at this area drying Anguera and Vallverd tributaries.

  20. Scenario-Based Impact Assessment of Land Use/Cover and Climate Changes on Watershed Hydrology in Heihe River Basin of Northwest China

    Directory of Open Access Journals (Sweden)

    Feng Wu

    2015-01-01

    Full Text Available This study evaluated hydrological impacts of potential climate and land use changes in Heihe River Basin of Northwest China. The future climate data for the simulation with Soil and Water Assessment Tool (SWAT were prepared using a dynamical downscaling method. The future land uses were simulated with the Dynamic Land Use System (DLS model by establishing Multinomial Logistic Regression (MNL model for six land use types. In 2006–2030, land uses in the basin will experience a significant change with a prominent increase in urban areas, a moderate increase in grassland, and a great decrease in unused land. Besides, the simulation results showed that in comparison to those during 1981–2005 the temperature and precipitation during 2006–2030 will change by +0.8°C and +10.8%, respectively. The land use change and climate change will jointly make the water yield change by +8.5%, while they will separately make the water yield change by −1.8% and +9.8%, respectively. The predicted large increase in future precipitation and the corresponding decrease in unused land will have substantial impacts on the watershed hydrology, especially on the surface runoff and streamflow. Therefore, to mitigate negative hydrological impacts and utilize positive impacts, both land use and climate changes should be considered in water resource planning for the Heihe River Basin.

  1. Non-motorized Winter Recreation Impacts to Snowmelt Erosion, Tronsen Basin, Eastern Cascades, Washington

    Science.gov (United States)

    Eagleston, Holly; Rubin, Charles

    2013-01-01

    Many recreation impact studies have focused on summer activities, but the environmental impact of winter recreation is poorly characterized. This study characterizes the impact of snowshoe/cross-country ski compaction and snowmelt erosion on trails. Trail cross-sectional profiles were measured before and after the winter season to map changes in erosion due to winter recreation. Compacted snow on the trail was 30 % more dense than snowpack off the trail before spring melt out. Snow stayed on the trail 7 days longer. Soil and organic material was transported after spring snowmelt with -9.5 ± 2.4 cm2 total erosion occurring on the trail transects and -3.8 ± 2.4 cm2 total erosion occurring on the control transect ( P = 0.046). More material was transported on the trail than on the control, 12.9± 2.4 versus 6.0 ± 2.4 cm2 ( P = 0.055), however, deposition levels remained similar on the trail and on the control. Snow compaction from snowshoers and cross-country skiers intensified erosion. Trail gradient was found to be significantly correlated to net changes in material on the trail ( R 2 = 0.89, ρ = -0.98, P = 0.005). This study provides a baseline, showing that non-motorized winter recreation does impact soil erosion rates but more studies are needed. Trail managers should consider mitigation such as water bars, culverts and avoiding building trails with steep gradients, in order to reduce loss of soils on trails and subsequent sedimentation of streams.

  2. Assessing the impacts of climate change on agricultural production in the Columbia River basin: incorporating water management

    Science.gov (United States)

    Adam, J. C.; Rajagopalan, K.; Stockle, C. O.; Yorgey, G.; Kruger, C. E.; Chinnayakanahalli, K.; Nelson, R.

    2014-12-01

    Changes in global population, food consumption and climate lead to a food security challenge for the future. Water resources, agricultural productivity and the relationships between them will to a large extent dictate how we address this challenge. Although food security is a global issue, impacts of climate change on water resources and agricultural productivity, as well as viability of adaptation strategies, are location specific; e.g., it is important to consider the regional regulatory environment. Our work focuses on the Columbia River basin (CRB) of the Pacific Northwest US. The water resources of the CRB are heavily managed to meet competing demands. There also exists a legal system for individuals/groups to obtain rights to use the publicly owned water resources, and the possibility of curtailing (i.e., restricting) some of these water rights in times of shortage. It is important to include an approximation of this water resource regulation and water rights curtailment process in modeling water availability and impacts of water shortages on agricultural production. The overarching objective of this work is to apply an integrated hydrologic-crop-water management modeling framework over the CRB to characterize the impacts of climate change on irrigation water demands, irrigation water availability, water shortages, and associated impacts in the 2030s. Results indicate that climate change has both positive and negative effects on agricultural production in the CRB and this varies by region and crop type. Certain watersheds that are already water stressed are projected to experience increasing stress in the future. Although, climate change results in increased water shortages and water rights curtailment in the region, this does not necessarily translate into an increased negative effect on yields; some crops are projected to increase in yield despite curtailment. This could be attributed to higher water use efficiency under elevated CO2 levels as well crops

  3. Impact of the climate change to shallow groundwater in Baltic artesian basin

    Science.gov (United States)

    Lauva, D.; Bethers, P.; Timuhins, A.; Sennikovs, J.

    2012-04-01

    The purpose of our work was to find the long term pattern of annual shallow ground water changes in region of Latvia, ground water level modelling for the contemporary climate and future climate scenarios and the model generalization to the Baltic artesian basin (BAB) region. Latvia is located in the middle part of BAB. It occupies about 65'000 square kilometers. BAB territory (480'000 square kilometres) also includes Lithuania, Estonia as well as parts of Poland, Russia, Belarus and the Baltic Sea. Territory of BAB is more than seven times bigger than Latvia. Precipitation and spring snow melt are the main sources of the ground water recharge in BAB territory. The long term pattern of annual shallow ground water changes was extracted from the data of 25 monitoring wells in the territory of Latvia. The main Latvian groundwater level fluctuation regime can be described as a function with two maximums (in spring and late autumn) and two minimums (in winter and late summer). The mathematical model METUL (developed by Latvian University of Agriculture) was chosen for the ground water modelling. It was calibrated on the observations in 25 gauging wells around Latvia. After the calibration we made calculations using data provided by an ensemble of regional climate models, yielding a continuous groundwater table time-series from 1961 to 2100, which were analysed and split into 3 time windows for further analysis: contemporary climate (1961-1990), near future (2021-2050) and far future (2071-2100). The daily average temperature, precipitation and humidity time series were used as METUL forcing parameters. The statistical downscaling method (Sennikovs and Bethers, 2009) was applied for the bias correction of RCM calculated and measured variables. The qualitative differences in future and contemporary annual groundwater regime are expected. The future Latvian annual groundwater cycle according to the RCM climate projection changes to curve with one peak and one drought point

  4. Trace Element Geochemistry of Matrix Glass from the Bedout Impact Structure,Canning Basin NW Australia

    Science.gov (United States)

    Poreda, R. J.; Basu, A. R.; Chakrabarti, R.; Becker, L.

    2004-12-01

    We report on geochemical and petrographic analysis of separated matrix glass from Lagrange-1 and Bedout-1 drill cores that penetrated the Bedout structure offshore NW Australia. The results support the conclusion that the Bedout structure was produced by a a major ET impact at the end-Permian that generated shock melted glass and impact breccias (Becker et al., Science, v.304, p.1469, 2004) The Bedout structure is a 30 km, circular, 1.5 km uplifted basment high that occurs on the passive margin offshore NW Australia. The isolated feature, covered by 3 km of Triassic to Recent sediments,is not consistent with any typical volcanic province (i.e. arc or hotspot volcanism). This hypothesis is supported by the unique mineralogy and chemistry of the matrix glass. At Lagrange, major elements crudely resemble low-K, Fe-Ti basalts while the trace element patterns have two distinct signatures. The lower 250 m of Lagrange (3260 - 3010 m depth) have essentially flat REE and "spider" patterns that superficially resemble some E-MORB; a signal not typically found in arc, hotspot or continental margin settings. The upper 150 meters (3000 - 2850m) of Lagrange and the entire Bedout core (3030 - 3070m) have similar light REE-enriched patterns but low levels of alkalis, alkaline-earths and high field strength elements. Again, the chemistry is not consistent with an arc or hotspot setting, based on the low Ba and extremely low Sr (30-110 ppm) concentrations. Based on the geophysical, chemical and petrologic evidence, we hypothesize that the Bedout structure formed as the result` of an ET impact with Permian age rift margin basalts and continental sediment. The basalts did not completely melt as evidenced by the abundance of large (1 mm) An50 plagioclase,that exist as both crystalline plag and shock melted maskelynite. Plagioclase is the major repository of Sr in basalts and the lack of a plagioclase contribution to the melt glass is reflected in the low Sr abundance. Shock

  5. Impact of Climate Change on Runoff in the Gilgel Abbay Watershed, the Upper Blue Nile Basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    Hailu Sheferaw Ayele

    2016-09-01

    Full Text Available Hydrological assessment is critical to the successful implementation of adaption measures. In this study, projections of seven global circulation models (GCMs associated with high and medium–low Representative Concentration Pathways (RCP 8.5 and RCP 4.5 for the period 2021–2040 and 2081–2100 were adopted to assess changes on runoffs in the Gilgel Abbay watershed, the upper Blue Nile basin. A weather generator was employed to generate daily temperature and precipitation to drive a hydrological model for impact assessment. Despite the projected magnitude of changes varied among different GCMs and RCPs, increasing runoffs in wet-season and decreasing in dry-season are observed in both periods, mainly attributed to the change in projected precipitation. Such changes are profound in cases of RCP 8.5 with respect to those of RCP 4.5 and in cases of 2081–2100 with respect to those of 2021–2040. Although the increasing runoffs would provide greater inflow to Lake Tana, the increase of precipitation in wet-season would imply a higher possibility of flash floods. On the other hand, decrease runoffs in dry-season further intensify existing shortage of irrigation water demand. These changes will have deleterious consequences on the economic wellbeing of the country and require successful implementation of adaption measures to reduce vulnerability.

  6. [Impact of the dynamics of human settlement on tsetse and trypanosomosis distribution in the Mouhoun river basin (Burkina Faso)].

    Science.gov (United States)

    Rouamba, J; Jamonneau, V; Sidibé, I; Solano, P; Courtin, F

    2009-03-01

    In Burkina Faso, the Mouhoun river basin (formerly "Black Volta") constitutes a historical focus of Human (HAT) and Animal (AAT) African Trypanosomoses, both transmitted by tsetse flies. Nowadays, HAT seems to have disappeared from this area, while AAT still causes severe economic losses. In order to explain these different epidemiological situations, we undertook a geographical study based on the analysis of aerial pictures between 1952 and 2007, and field surveys to collect medical, entomological, and veterinary data on trypanosomoses. Our results suggest that in this area, landscapes have been dramatically modified as a consequence of population growth, and in turn have had an impact on the number and distribution of tsetse flies. Combined with the historical medical action on HAT which probably led to the disappearance of T. b. gambiense, this environmental degradation and the development of hydrological structures provide explanations for the local disappearance of HAT, and for the maintenance of AAT. It appears necessary to extrapolate these studies to other areas in order to identify the factors explaining the presence/absence of trypanosomoses in the context of human population growth and climatic changes, in order to help to target priority areas for the control of these diseases.

  7. The impact of hydroelectric project development on the ethnobotany of the Alaknanda river basin of Western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Khilendra Singh Kanwal

    2015-12-01

    Full Text Available Background: This study focuses on the ethnoflora used by local communities in the Alaknanda river basin of Uttarakhand state in Western Himalaya, India. The objectives of the study are to collect ethnobotanical information, to assess the impact of hydropower projects on ethnoflora and to suggest conservation and management measures for the protection of ethnoflora. Material and Methods: A well-designed questionnaire based survey was conducted in the ten villages of the study area to collect ethnobotanical information. The conservation status of plants was also evaluated following the IUCN Red list, the Red Data Book of Indian Plants and the CITES criteria. Results: A total of 136 plant species belonging to 61 families and 112 genera were used by local communities for various ethnobotanical purposes. The majority of plant species were used for medicinal purposes (96 spp., followed by fodder (46 spp., wild edibles (31 spp., fuel (29 spp., timber (17 spp., fish poison (9 spp., agriculture implements (6 spp., fibre (6 spp., religious use (6 spp. and handicraft (1 sp.. For the preparation of herbal medicine, rural people of the region use different parts of medicinal plants such as the whole plant (20% followed by roots/rhizomes/tubers (20%, leaf (18%, fruit (10%, seed (9%, bark (9%, stem (6%, flowers (6% and resin (2%. Conclusions: Development of hydropower projects will influence the diversity and distribution of ethnoflora in the region. Therefore, for the conservation of the ethnoflora of the area, conservation and management measures have been suggested.

  8. Climate model based consensus on the hydrologic impacts of climate change to the Rio Lempa basin of Central America

    Directory of Open Access Journals (Sweden)

    E. P. Maurer

    2009-02-01

    Full Text Available Temperature and precipitation from 16 climate models each using two emissions scenarios (lower B1 and mid-high A2 were used to characterize the range of potential climate changes for the Rio Lempa basin of Central America during the middle (2040–2069 and end (2070–2099 of the 21st century. A land surface model was applied to investigate the hydrologic impacts of these changes, focusing on inflow to two major hydropower reservoirs. By 2070–2099 the median warming relative to 1961–1990 was 1.9°C and 3.4°C under B1 and A2 emissions, respectively. For the same periods, the models project median precipitation decreases of 5.0% (B1 and 10.4% (A2. Median changes by 2070–2099 in reservoir inflow were 13% (B1 and 24% (A2, with largest flow reductions during the rising limb of the seasonal hydrograph, from June through September. Frequency of low flow years increases, implying decreases in firm hydropower capacity of 33% to 53% by 2070–2099.

  9. Assessing Climate Change Impact on Gilgel Abbay and Gumara Watershed Hydrology, the Upper Blue Nile Basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    Hailu Sheferaw Ayele

    2016-01-01

    Full Text Available Climate change and variability have significant influences on hydrological cycles and the availability of water in the Horn of Africa. Projections of six General Circulation Models (GCMs in association with high (A2 and low (B1 emission scenarios were adopted in this study from the Special Report on Emission Scenarios (SRES for the period 2020 - 2039 to assess the impacts of climate changes on the Gilgel Abbay and Gumara watershed hydrology, the upper Blue Nile basin, Ethiopia. The GCMs selected were screened in accordance with baseline climate statistics of study areas. A weather generator was employed to generate daily temperature and precipitation to drive the General Water Loading Function (GWLF hydrological model for simulating runoffs. Projected changes in temperature differences and precipitation ratios relative to the baseline were analyzed to explain the variations in evapotranspiration and the influences on runoff. Despite the fact that the projected magnitude varies among GCMs, increasing runoff in both wet and dry seasons was observed for both watersheds, attributable mainly to the increase in precipitation projected by most GCMs. In contrast to the great increases in runoff, variations in evapotranspiration are less significant. The projected runoff in both watersheds implies increased potential for promoting agricultural irrigation in the dry season. Furthermore, it would allow greater inflow to Lake Tana, the largest contributor to the Ethiopian Renaissance Dam on the Blue Nile. Therefore, concerned local, state, and federal government organizations shall be prepared to harness opportunities from the projected increase in runoff.

  10. Predicting future changes in climate and its impact on change in land use: a case study of Cauvery Basin

    Science.gov (United States)

    Poyil, Rohith P.; Dhanalakshmi, S.; Goyal, Pramila

    2016-05-01

    The study involves the climate change prediction and its effects over a local sub grid scale of smaller area in Cauvery basin. The consequences of global warming due to anthropogenic activities are reflected in global as well as regional climate in terms of changes in key climatic variables such as temperature, precipitation, humidity and wind speed. The key objectives of the study are to define statistical relationships between different climate parameters, to estimate the sensitivities of climate variables to future climate scenarios by integrating with GIS and to predict the land use/ land cover change under the climate change scenarios. The historical data set was analyzed to predict the climate change and its impact on land use/land cover (LULC) is observed by correlating the Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) values for two different times for the same area. It is so evident that due to the rise in temperature there is a considerable change in the land use affecting the vegetation index; increased temperature results in very low NDVI values or vegetation abundance.

  11. Projecting the land cover change and its environmental impacts in the Cedar River Basin in the Midwestern United States

    Science.gov (United States)

    Wu, Yiping; Liu, Shuguang; Sohl, Terry L.; Young, Claudia

    2013-01-01

    The physical surface of the Earth is in constant change due to climate forcing and human activities. In the Midwestern United States, urban area, farmland, and dedicated energy crop (e.g., switchgrass) cultivation are predicted to expand in the coming decades, which will lead to changes in hydrological processes. This study is designed to (1) project the land use and land cover (LULC) by mid-century using the FORecasting SCEnarios of future land-use (FORE-SCE) model under the A1B greenhouse gas emission scenario (future condition) and (2) assess its potential impacts on the water cycle and water quality against the 2001 baseline condition in the Cedar River Basin using the physically based soil and water assessment tool (SWAT). We compared the baseline LULC (National Land Cover data 2001) and 2050 projection, indicating substantial expansions of urban area and pastureland (including the cultivation of bioenergy crops) and a decrease in rangeland. We then used the above two LULC maps as the input data to drive the SWAT model, keeping other input data (e.g., climate) unchanged to isolate the LULC change impacts. The modeling results indicate that quick-response surface runoff would increase significantly (about 10.5%) due to the projected urban expansion (i.e., increase in impervious areas), and the baseflow would decrease substantially (about 7.3%) because of the reduced infiltration. Although the net effect may cause an increase in water yield, the increased variability may impede its use for public supply. Additionally, the cultivation of bioenergy crops such as switchgrass in the newly added pasture lands may further reduce the soil water content and lead to an increase in nitrogen loading (about 2.5% increase) due to intensified fertilizer application. These study results will be informative to decision makers for sustainable water resource management when facing LULC change and an increasing demand for biofuel production in this area.

  12. Projected impacts of climate change on groundwater and stormflow in a humid, tropical catchment in the Ugandan Upper Nile Basin

    Directory of Open Access Journals (Sweden)

    D. G. Kingston

    2010-03-01

    Full Text Available The changing availability of freshwater resources is likely to be one of the most important consequences of projected 21st century climate change for both human and natural systems. However, substantial uncertainty remains regarding the precise impacts of climate change on water resources, due in part to uncertainty in GCM projections of climate change. Here we explore the potential impacts of climate change on water resources in a humid, tropical catchment (the River Mitano in the Upper Nile Basin of Uganda. Uncertainty associated with GCM structure and climate sensitivity is explored, as well as from parameter specification within hydrological models. This is achieved by running pattern-scaled GCM output through a semi-distributed hydrological model (developed using SWAT of the catchment. Importantly, use of pattern-scaled GCM output allows investigation of specific thresholds of global climate change including the purported 2 °C threshold of "dangerous" climate change. In-depth analysis of results based on HadCM3 climate scenarios shows that annual river discharge first increases, then declines with rising global mean air temperature. A coincidental shift from a bimodal to unimodal discharge regime also results from a projected reduction in baseflow (groundwater discharge. Both of these changes occur after a 4 °C rise in global mean air temperature. These results are, however, highly GCM dependent in both the magnitude and direction of change. This dependence stems primarily from projected differences in GCM scenario precipitation rather than temperature. GCM-related uncertainty is far greater than that associated with climate sensitivity or hydrological model parameterisation.

  13. A population model of the impact of a rodenticide containing strychnine on Great Basin Gophersnakes (Pituophis catenifer deserticola).

    Science.gov (United States)

    Bishop, Christine A; Williams, Kathleen E; Kirk, David A; Nantel, Patrick; Reed, Eric; Elliott, John E

    2016-09-01

    Strychnine is a neurotoxin and an active ingredient in some rodenticides which are placed in burrows to suppress pocket gopher (Thomomys talpoides) populations in range and crop land in western North America. The population level impact was modelled of the use of strychnine-based rodenticides on a non-target snake species, the Great Basin Gophersnake (Pituophis catenifer deserticola), which is a predator of pocket gopher and a Species at Risk in Canada. Using information on population density, demographics, and movement and habitat suitability for the Gophersnake living in an agricultural valley in BC, Canada, we estimated the impact of the poisoning of adult snakes on the long-term population size. To determine the area where Gophersnakes could be exposed to strychnine, we used vendor records of a rodenticide, and quantified the landcover areas of orchards and vineyards where the compound was most commonly applied. GIS analysis determined the areas of overlap between those agricultural lands and suitable habitats used by Gophersnakes. Stage-based population matrix models revealed that in a low density (0.1/ha) population scenario, a diet of one pocket gopher per year wherein 10 % of them carried enough strychnine to kill an adult snake could cause the loss of 2 females annually from the population and this would reduce the population by 35.3 % in 25 years. Under the same dietary exposure, up to 35 females could die per year in a high density (0.4/ha) population which would result in a loss of 50 % of adults in 25 years.

  14. Potential Impacts of Climate Warming on Water Supply Reliability in the Tuolumne and Merced River Basins, California

    Science.gov (United States)

    Kiparsky, Michael; Joyce, Brian; Purkey, David; Young, Charles

    2014-01-01

    We present an integrated hydrology/water operations simulation model of the Tuolumne and Merced River Basins, California, using the Water Evaluation and Planning (WEAP) platform. The model represents hydrology as well as water operations, which together influence water supplied for agricultural, urban, and environmental uses. The model is developed for impacts assessment using scenarios for climate change and other drivers of water system behavior. In this paper, we describe the model structure, its representation of historical streamflow, agricultural and urban water demands, and water operations. We describe projected impacts of climate change on hydrology and water supply to the major irrigation districts in the area, using uniform 2°C, 4°C, and 6°C increases applied to climate inputs from the calibration period. Consistent with other studies, we find that the timing of hydrology shifts earlier in the water year in response to temperature warming (5–21 days). The integrated agricultural model responds with increased water demands 2°C (1.4–2.0%), 4°C (2.8–3.9%), and 6°C (4.2–5.8%). In this sensitivity analysis, the combination of altered hydrology and increased demands results in decreased reliability of surface water supplied for agricultural purposes, with modeled quantity-based reliability metrics decreasing from a range of 0.84–0.90 under historical conditions to 0.75–0.79 under 6°C warming scenario. PMID:24465455

  15. Evidence for Noachian flood volcanism in Noachis Terra, Mars, and the possible role of Hellas impact basin tectonics

    Science.gov (United States)

    Rogers, A. D.; Nazarian, A. H.

    2013-05-01

    Spectral and imaging data sets from Mars Reconnaissance Orbiter and Mars Odyssey, as well as spectral and topographic data from Mars Global Surveyor, are used to understand the origin of in-place rock units found in the intercrater plains and Hellas circumferential graben floors of Noachis Terra, Mars. The rocky units are interpreted as effusive volcanic plains on the basis of broad areal extent, structural competence, association with topographic lows, distinct mineralogy from regolith, and lack of sedimentary textures or minerals associated with aqueous processes. Some rocky expanses contain at least two compositionally distinct units. The relatively light-toned unit exhibits a higher plagioclase/pyroxene ratio than the lower, dark-toned unit. Both units exhibit ~10% olivine enrichment compared to surrounding regolith. These units are heavily degraded and exhibit crater model ages between ~3.80 and 4.0 Ga, making these some of the oldest preserved volcanic plains accessible by remote sensing. They are found in association with Hellas ring structures, where the westward extent of these rocky units is limited to the outermost ring structure. Fracturing associated with the Hellas impact may have enabled magmas to ascend from the base of the crust in the circum-Hellas region. Identification of these units as volcanic materials extends previous estimates for volume of outgassed volatiles. Though the estimated volcanic volume increase is minor, the local effects could have been significant. The role of multi-ring impact basins in providing a spatial control on Martian highlands volcanism and subsurface mineralization may have been underestimated in the past.

  16. Ecological Impact of Climate Change on Leaf Economic Strategies Across the Paleocene- Eocene Thermal Maximum, Bighorn Basin, Wyoming

    Science.gov (United States)

    Royer, D. L.; Currano, E. D.; Wilf, P.; Wing, S. L.; Labandeira, C. C.; Lovelock, E. C.

    2007-12-01

    Deciphering the ecological impacts of climate change is a key priority for paleontologists and ecologists alike. An important ecological metric in vegetated settings is the leaf economics spectrum, which represents an adaptive continuum running from rapid resource acquisition to maximized resource retention. This spectrum is comprised of a large number of coordinated traits, including leaf mass per area (LMA), leaf lifespan, photosynthetic rate, nutrient concentration, and palatability to herbivores. Here we apply a recently developed technique for reconstructing LMA to a suite of four isotaphonomic fossil plant sites spanning the Paleocene-Eocene thermal maximum (PETM) in the Bighorn Basin, Wyoming, USA. This technique is based on the biomechanical scaling between petiole width and leaf mass, and it has been calibrated with 65 present-day sites from five continents and tested on two well-known Eocene fossil localities (Bonanza, Utah and Republic, Washington). There are no significant differences in LMA among plants across the PETM. This stasis is present despite a backdrop of extreme climate change during the PETM in this region, including a three-to-four-fold increase in atmospheric CO2, an ~5 °C rise in temperature, and possible drying. Moreover, quantitative measurements of insect herbivory show, on average, a two-fold increase during the PETM relative to before and after the event. We interpret our results to suggest that leaf-economic relationships can, in some situations, partially decouple. More specifically, our documented increase in insect herbivory during the PETM with no concomitant decrease in LMA implies that during this interval less carbon was being captured by plants per unit of investment. Because the rate and magnitude of climate change during the PETM is similar to present-day anthropogenic changes, our results may provide clues for predictions of ecological impacts in the near future.

  17. Modelling the impact of agroforestry on hydrology of Mara River basin in East Africa using a distributed model

    Science.gov (United States)

    Mwangi, Hosea; Julich, Stefan; Patil, Sopan; McDonald, Morag; Feger, Karl-Heinz

    2016-04-01

    Land use change is one of the main drivers of change of watershed hydrology. The effect of forestry related land use changes (e.g., afforestation, deforestation, agroforestry) on watershed hydrology depends on climate, watershed characteristics and watershed scale. The Soil and Water Assessment Tool (SWAT) model was calibrated, validated and used to simulate the impact of agroforestry on the water balance in Mara River Basin (MRB) in East Africa. Model performance was assessed by Nash-Sutcliffe Efficiency (NSE) and Kling-Gupta Efficiency (KGE). The NSE (and KGE) values for calibration and validation were 0.77 (0.88) and 0.74 (0.85) for the Nyangores sub-watershed and 0.78 (0.89) and 0.79 (0.63) for the entire MRB. It was found that agroforestry in the catchment would generally reduce surface runoff, mainly due to enhanced infiltration. However, it would also increase evapotranspiration and consequently reduce the baseflow and the overall water yield, which was attributed to increased water use by trees. Spatial scale was found to have a significant effect on water balance; the impact of agroforestry was higher at the smaller headwater catchment (Nyangores) than for the larger watershed (entire MRB). However, the rate of change in water yield with increase in area under agroforestry was different for the two and could be attributed to the spatial variability of climate within MRB. Our results suggest that direct extrapolation of the findings from a small sub-catchment to a larger watershed may not always be accurate. These findings could guide watershed managers on the level of trade-offs to make between reduced water yields and other benefits (e.g., soil erosion control, improved soil productivity) offered by agroforestry.

  18. Local assessment of vulnerability to climate change impacts on water resources in the Upper Thukela River Basin, South Africa : Recommendations for Adaptation

    OpenAIRE

    Andersson, Lotta; Wilk, Julie; Graham, Phil; Warburton, Michele

    2009-01-01

    This report originates from a project entitled Participatory Modelling for Assessment of Local Impacts of Climate Variability and Change on Water Resources (PAMO), financed by the Swedish Development Agency and Research Links cooperation (NRF and the Swedish Research Council). The project is based on interactions between stakeholders in the Mhlwazini/Bergville area of the Thukela River basin, climate and water researchers from the University of KwaZulu-Natal (Pietermaritzburg Campus) and the ...

  19. Reservoir impacts downstream in highly regulated river basins: the Ebro delta and the Guadalquivir estuary in Spain

    OpenAIRE

    2016-01-01

    Regulation by reservoirs affects both the freshwater regime and the sediment delivery at the area downstream, and may have a significant impact on water quality in the final transitional water bodies. Spain is one the countries with more water storage capacity by reservoirs in the world. Dense reservoir networks can be found in most of the hydrographic basins, especially in the central and southern regions. The spatial redistribution of the seasonal and annual water storage ...

  20. The Caribbean Basin Economic Recovery Act--1983: Its Impact on the Economic/Political Stabilities within the Region.

    Science.gov (United States)

    1991-04-25

    otherwise had been opposed by President Reagan. The final public law 98-67 is titled: "INTEREST AND DIVIDEND TAX COMPLIANCE ACT OF 1983-CARIBBEAN BASIN...ECONOMIC RECOVERY ACT". Title I Is the "INTEREST AND DIVIDEND TAX COMPLIANCE ", and Title II contains the "CARIBBEAN BASIN INITIATIVE". Title II contains

  1. The Impact of Water Scarcity on Egyptian National Security and on Regional Security in the Nile River Basin

    Science.gov (United States)

    2012-06-08

    for the government to deal with this problem and create the appropriate climate to reconsolidate the relations with the Nile Basin countries, which......the border of the DRC to the west . Table 3 depicts water and land resources in the Nile Basin

  2. Petrology of Impact-Melt Rocks at the Chicxulub Multiring Basin, Yucatan, Mexico

    Science.gov (United States)

    Schuraytz, Benjamin C.; Sharpton, Virgil L.; Marin, Luis E.

    1994-01-01

    Compositions and textures of melt rocks from the upper part of the Chicxulub structure are typical of melt rocks at other large terrestrial impact structures. Apart from variably elevated iridium concentrations (less than 1.5 to 13.5 +/- 0.9 ppb) indicating nonuniform dissemination of a meteoritic component, bulk rock and phenocryst compositions imply that these melt rocks were derived exclusively from continental crust and platform-sediment target lithologies. Modest differences in bulk chemistry among samples from wells located approximately 40 km apart suggest minor variations in relative contributions of these target lithologies to the melts. Subtle variations in the compositions of early-formed pyroxene and plagioclase also support minor primary differences in chemistry between the melts. Evidence for pervasive hydrothermal alteration of the porous mesostasis includes albite, K-feldspar, quartz, epidote, chlorite, and other phyllosilicates, as well as siderophile element-enriched sulfides, suggesting the possibility that Chicxulub, like Sudbury, may host important ore deposits.

  3. Modeling ecohydrological impacts of land management and water use in the Silver Creek Basin, Idaho

    DEFF Research Database (Denmark)

    Loinaz, Maria Christina; Gross, Dayna; Unnasch, Robert;

    2014-01-01

    A number of anthropogenic stressors, including land use change and intensive water use, have caused stream habitat deterioration in arid and semiarid climates throughout the western U.S. These often contribute to high stream temperatures, a widespread water quality problem. Stream temperature....... In this study, we predict relative impacts of different stressors using an integrated catchment-scale ecohydrological model that simulates hydrological processes, stream temperature, and fish growth. This type of model offers a suitable measure of ecosystem services because it provides information about...... the reproductive capability of fish under different conditions. We applied the model to Silver Creek, Idaho, a stream highly valued for its world-renowned trout fishery. The simulations indicated that intensive water use by agriculture and climate change are both major contributors to habitat degradation...

  4. Impact of Sub-grid Soil Textural Properties on Simulations of Hydrological Fluxes at the Continental Scale Mississippi River Basin

    Science.gov (United States)

    Kumar, R.; Samaniego, L. E.; Livneh, B.

    2013-12-01

    Knowledge of soil hydraulic properties such as porosity and saturated hydraulic conductivity is required to accurately model the dynamics of near-surface hydrological processes (e.g. evapotranspiration and root-zone soil moisture dynamics) and provide reliable estimates of regional water and energy budgets. Soil hydraulic properties are commonly derived from pedo-transfer functions using soil textural information recorded during surveys, such as the fractions of sand and clay, bulk density, and organic matter content. Typically large scale land-surface models are parameterized using a relatively coarse soil map with little or no information on parametric sub-grid variability. In this study we analyze the impact of sub-grid soil variability on simulated hydrological fluxes over the Mississippi River Basin (≈3,240,000 km2) at multiple spatio-temporal resolutions. A set of numerical experiments were conducted with the distributed mesoscale hydrologic model (mHM) using two soil datasets: (a) the Digital General Soil Map of the United States or STATSGO2 (1:250 000) and (b) the recently collated Harmonized World Soil Database based on the FAO-UNESCO Soil Map of the World (1:5 000 000). mHM was parameterized with the multi-scale regionalization technique that derives distributed soil hydraulic properties via pedo-transfer functions and regional coefficients. Within the experimental framework, the 3-hourly model simulations were conducted at four spatial resolutions ranging from 0.125° to 1°, using meteorological datasets from the NLDAS-2 project for the time period 1980-2012. Preliminary results indicate that the model was able to capture observed streamflow behavior reasonably well with both soil datasets, in the major sub-basins (i.e. the Missouri, the Upper Mississippi, the Ohio, the Red, and the Arkansas). However, the spatio-temporal patterns of simulated water fluxes and states (e.g. soil moisture, evapotranspiration) from both simulations, showed marked

  5. An Analysis of Land Use Change Dynamics and Its Impacts on Hydrological Processes in the Jialing River Basin

    Directory of Open Access Journals (Sweden)

    Tao Zhang

    2014-12-01

    Full Text Available Land use changes are important aspects of global change and affect regional water cycles, environmental quality, biodiversity and terrestrial ecosystems. To understand the temporal and spatial land use change in the Jialing River Basin and its impacts on the hydrological cycle, land use change models and the variable infiltration capacity (VIC model were applied separately to the Jialing River Basin. Real change and final change were analyzed to determine the consequences of land use changes and their hydrological consequences. Real change is defined as the total variation during a fixed period, including increases and decreases. Thus, real change is the sum of the absolute values of the decrease and the increase. Final change is defined as the difference between the beginning and end of a given period for a specific factor. Overall, the amounts of settlement and shrub land area changed significantly in the entire Jialing River (with final change rates of 20.77% and −16.07%, respectively, and real change rates of 34.2% and 30.1%, respectively, from 1985 to 1995, as well as final and real change rates of 29.37%, 12.40%, 39.9% and 32.8%, respectively, from 1995 to 2000. Compared with the final change, the real change highlighted the rate of change and the change in woodland area. The land use changes in the Lueyang (LY, Shehong (SH and Fengtan (FT subcatchments were more dynamic than in the other subcatchments. The economy, population and macro-policy were the main factors responsible for driving the land use changes. The decrease in woodland area in the LY subcatchment corresponded with an increase in evapotranspiration (ET and with decreases in the other hydrological elements. Overall, the final changes in the hydrological elements in the LY, SH and FT subcatchments were not significant due to the average and compensation effects. The LY subcatchment was mainly affected by the average effect, whereas the SH and FT subcatchments were affected

  6. On the Edge: the Impact of Climate Change, Climate Extremes, and Climate-driven Disturbances on the Food-Energy-Water Nexus in the Colorado River Basin

    Science.gov (United States)

    Bennett, K. E.; McDowell, N. G.; Tidwell, V. C.; Xu, C.; Solander, K.; Jonko, A. K.; Wilson, C. J.; Middleton, R. S.

    2016-12-01

    The Colorado River Basin (CRB) is a critical watershed in terms of vulnerability to climate change and supporting the food-energy-water nexus. Climate-driven disturbances in the CRB—including wildfire, drought, and pests—threaten the watershed's ability to reliably support a wide array of ecosystem services while meeting the interrelated demands of the food-energy-water nexus. Our work illustrates future changes for upper Colorado River headwater basins using the Variable Infiltration Capacity hydrologic model driven by downscaled CMIP5 global climate data coupled with pseudo-dynamic vegetation shifts associated with changing fire and drought conditions. We examine future simulated streamflow within the context of an operational model framework to consider the impacts on water operators and managers who rely upon the timely and continual delivery of streamflow. We focus on results for a large case study basin within the CRB—the San Juan River—showing future scenarios where this ecosystem is pushed towards the extremes. Our findings illustrate that landscape change in the CRB cause delayed snowmelt and increased evapotranspiration from shrublands, which leads to increases in the frequency and magnitude of both droughts and floods within disturbed systems. By 2080, coupled climate and landscape change produces a dramatically altered hydrograph resulting in larger peak flows, reduced lower flows, and lower overall streamflow. Operationally, this results in increased future water delivery challenges and lower reservoir storages driven by changes in the headwater basins. Ultimately, our work shows that the already-stressed CRB ecosystem could, in the future, be pushed over a tipping point, significantly impacting the basin's ability to reliably supply water for food, energy, and urban uses.

  7. Land use, land cover, and climate change across the Mississippi Basin: Impacts on selected land and water resources

    Science.gov (United States)

    Foley, Jonathan A.; Kucharik, Christopher J.; Twine, Tracy E.; Coe, Michael T.; Donner, Simon D.

    The Mississippi Basin is the third largest drainage basin in the world and is home to one of the most productive agricultural regions on Earth. Here we discuss how land use/land cover change and climatic variability may be affecting some key environmental processes across the Mississippi and how these, in turn, affect the flow of selected ecosystem goods and services in the region. Specifically, we consider the recent history of land use/land cover change, crop yields, basin river flow and hydrology, and large-scale water quality in the Mississippi Basin. We find that agricultural activities may have had a profound influence on the basin and may have shifted the flow of many ecosystem goods and services into agricultural commodities, at the expense of altering many of the important biogeochemical linkages between atmosphere, land, and water.

  8. Impacts of extreme events of drought and flood on local communities of Amazon basin

    Science.gov (United States)

    Borma, L. D.; Roballo, S.; Zauner, M.; Nascimento, V. F.

    2013-05-01

    contingent of about 50% of rural homeless during this event. On the ther side, during the extreme droughts, crops and cattle are likely to perish due to drought. The prolonged dry season threatens local ichthyofauna, promoting an increase in fish mortality. In 1997/98 and 2005 episodes were recorded about 3 months of negative anomalies of discharge, while in 2010, there were about 4 months of negative anomalies during the low water period. According to the data obtained from the Civil Defense, flood events would be more impactful to the local community than the drought ones. However, the absence of quantitative indicators hinders a more precise analysis of the real impacts of drought and flood events in the region. In fact, during the dry season two aspects of extreme importance need to be better addressed: i) the fact that the population of one of the wettest regions of the planet does not have a good water supply for human being, and ii) what are the impacts of extreme drought on the cycle of reproduction of species of local fish fauna?

  9. Impacts of Groundwater Recharge from Rubber Dams on the Hydrogeological Environment in Luoyang Basin, China

    Science.gov (United States)

    Dong, Shaogang; Liu, Baiwei; Liu, Huamin; Wang, Shidong; Wang, Lixin

    2014-01-01

    In the rubber dam's impact area, the groundwater total hardness (TH) has declined since 2000, ultimately dropping to 100–300 mg/L in 2012. pH levels have shown no obvious changes. NH4-N concentration in the groundwater remained stable from 2000 to 2006, but it increased from 2007 to 2012, with the largest increase up to 0.2 mg/L. NO3-N concentration in the groundwater generally declined in 2000–2006 and then increased from 2007; the largest increase was to 10 mg/L in 2012. Total dissolved solids (TDS) of the groundwater showed a general trend of decline from 2000 to 2009, but levels increased after 2010, especially along the south bank of the Luohe River where the largest increase recorded was approximately 100 mg/L. This study has shown that the increases in the concentrations of NH4-N and NO3-N were probably caused by changes in groundwater levels. Nitrates adsorbed by the silt clay of aeration zone appear to have entered the groundwater through physical and chemical reactions. TDS increased because of groundwater evaporation and some soluble ions entered the groundwater in the unsaturated zone. The distance of the contaminant to the surface of the aquifer became shorter due to the shallow depth of groundwater, resulting in the observed rise in pollutant concentrations more pronounced. PMID:25126593

  10. Projected climate change impacts upon dew yield in the Mediterranean basin

    Energy Technology Data Exchange (ETDEWEB)

    Tomaszkiewicz, M. [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon); Abou Najm, M., E-mail: majdian@aub.edu.lb [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon); Beysens, D. [Physique et Mecanique des Milieux Heterogenes, UMR 7636 CNRS — ESPCI, Universite Pierre et Marie Curie — Universite Paris Diderot, 10 rue Vauquelin, 75005 Paris (France); Service des Basses Temperatures, CEA-Grenoble & Universite Joseph Fourier, Grenoble (France); OPUR, 60 rue Emeriau, 75015 Paris (France); Alameddine, I. [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon); Bou Zeid, E. [Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08540 (United States); El-Fadel, M. [Department of Civil & Environmental Engineering, Faculty of Engineering & Architecture, American University of Beirut, Beirut (Lebanon)

    2016-10-01

    Water scarcity is increasingly raising the need for non-conventional water resources, particularly in arid and semi-arid regions. In this context, atmospheric moisture can potentially be harvested in the form of dew, which is commonly disregarded from the water budget, although its impact may be significant when compared to rainfall during the dry season. In this study, a dew atlas for the Mediterranean region is presented illustrating dew yields using the yield data collected for the 2013 dry season. The results indicate that cumulative monthly dew yield in the region can exceed 2.8 mm at the end of the dry season and 1.5 mm during the driest months, compared to < 1 mm of rainfall during the same period in some areas. Dew yields were compared with potential evapotranspiration (PET) and actual evapotranspiration (ET) during summer months thus highlighting the role of dew to many native plants in the region. Furthermore, forecasted trends in temperature and relative humidity were used to estimate dew yields under future climatic scenarios. The results showed a 27% decline in dew yield during the critical summer months at the end of the century (2080). - Highlights: • Dew atlas for Mediterranean region is presented. • Cumulative dew yields can exceed 2.8 mm at the end of the dry season. • Dew yields compared with PET and ET show the role of dew to many native plants. • Forecasted trends under future climatic scenarios show a 27% decline in dew yield.

  11. Impacts of Groundwater Recharge from Rubber Dams on the Hydrogeological Environment in Luoyang Basin, China

    Directory of Open Access Journals (Sweden)

    Shaogang Dong

    2014-01-01

    Full Text Available In the rubber dam’s impact area, the groundwater total hardness (TH has declined since 2000, ultimately dropping to 100–300 mg/L in 2012. pH levels have shown no obvious changes. NH4-N concentration in the groundwater remained stable from 2000 to 2006, but it increased from 2007 to 2012, with the largest increase up to 0.2 mg/L. NO3-N concentration in the groundwater generally declined in 2000–2006 and then increased from 2007; the largest increase was to 10 mg/L in 2012. Total dissolved solids (TDS of the groundwater showed a general trend of decline from 2000 to 2009, but levels increased after 2010, especially along the south bank of the Luohe River where the largest increase recorded was approximately 100 mg/L. This study has shown that the increases in the concentrations of NH4-N and NO3-N were probably caused by changes in groundwater levels. Nitrates adsorbed by the silt clay of aeration zone appear to have entered the groundwater through physical and chemical reactions. TDS increased because of groundwater evaporation and some soluble ions entered the groundwater in the unsaturated zone. The distance of the contaminant to the surface of the aquifer became shorter due to the shallow depth of groundwater, resulting in the observed rise in pollutant concentrations more pronounced.

  12. Projected impacts of climate change on hydrology, water resource use and adaptation needs for the Chu and Talas cross-border rivers basin, Central Asia

    Science.gov (United States)

    Shamil Iliasov, Shamil; Dolgikh, Svetlana; Lipponen, Annukka; Novikov, Viktor

    2014-05-01

    The observed long-term trends, variability and projections of future climate and hydrology of the Chu and Talas transboundary rivers basin were analysed using a common approach for Kazakhstan and Kyrgyzstan parts of the basin. Historical, current and forecasted demands and main uses of water in the basin were elaborated by the joint effort of both countries. Such cooperative approach combining scientific data, water practitioners' outlook with decision making needs allowed the first time to produce a comprehensive assessment of climate change impacts on water resources in the Chu-Talas transboundary rivers basin, identify future needs and develop the initial set of adaptation measures and recommendations. This work was carried out under the project "Promoting Cooperation to Adapt to Climate Change in the Chu and Talas Transboundary Basin", supported by the United Nations Economic Commission for Europe (UNECE) and the United Nations Development Programme (UNDP). Climate change projections, including air temperatures and rainfall in the 21st century were determined with a spatial resolution 0.5 degrees based on the integration of 15 climate change model outputs (derived from IPCC's 4th Assessment Report, and partially 5th Assessment Report) combined with locally-designed hydrology and glacier models. A significant increase in surface air temperatures by 3-6°C may be expected in the basin area, especially in summer and autumn. This change is likely to be accompanied by rainfall increase during the cold season and a decrease in the warm half of the year. As a result, a deterioration of moisture conditions during the summer-autumn period is possible. Furthermore, milder winters and hotter summers can be expected. Mountains will likely receive more liquid precipitation, than snow, while the area and volume of glaciers may significantly reduce. Projected changes in climate and glaciers have implications for river hydrology and different sectors of the economy dependent

  13. Assessment of dam impacts on river flow regimes and water quality: a case study of the Huai River Basin in P. R. China

    Institute of Scientific and Technical Information of China (English)

    XIA Jun; ZHANG Yong-yong; WANG Gang-sheng

    2008-01-01

    The Huai River Basin is a unique area in P.R.China with the highest densities of population and water projects. It is also subject to the most serious water pollution. We proposed a distributional SWAT (Soil and Water Assessment Tool) model coupled with a water quality-quantity balance model to evaluate dam impacts on river flow regimes and water quality in the middle and upper reaches of the Huai River Basin. We calibrated and validated the SWAT model with data from 29 selected cross-sections in four typical years (1971, 1981, 1991 and 1999) and used scenario analysis to compensate for the unavailability of historical data regarding uninterrupted river flows before dam and floodgate construction, a problem of prediction for ungauged basins. The results indicate that dam and floodgate operations tended to reduce runoff, decrease peak value and shift peaking time.The contribution of water projects to river water quality deterioration in the concerned river system was between 0 to 40%, while pollutant discharge contributed to 60% to 100% of the water pollution. Pollution control should therefore be the key to the water quality rehabilitation in the Huai River Basin.

  14. A water quality analysis system to evaluate the impact of agricultural activities on N outflow in river basins in Japan

    Institute of Scientific and Technical Information of China (English)

    Makoto Takeuchi; Sunao Itahashi; Masanori Saito

    2005-01-01

    We have developed a personal-computer-based water quality analysis system for river basins. The system estimates potential N outflow by model and calculates actual N outflow from monitoring data. For the former it uses the potential load factor method to estimate annual nitrogen load from various sources and runoff potential from each area of land in a basin. For the latter it analyzes water quality monitoring data in relation to meteorological data. We used the system to analyze N outflow in basins around Lake Kasumigaura and the Yahagi River in central Honshu, Japan. The land around Lake Kasumigaura is rather flat, and about 25% is periodically flooded for rice and lotus cultivation. The land around the Yahagi River is mountainous, and much less land is flooded. In the Yahagi River basin the actual N outflow agreed closely with the potential. However, the actual N outflow in the basin around Lake Kasumigaura was much less than the potential, suggesting that a large part of the N load is denitrified in flooded soils. This further indicates that a sequence of different land uses including flooded rice fields is an important factor determining N outflow in basins in Japan. On the basis of the above analyses, we incorporated a denitrification model into the system that enables us to estimate N balance in a designated basin;this system may be helpful in the formulation of scenarios of land use andsoil management for improving water quality.

  15. Potential impact of Chironomus plumosus larvae on hypolimnetic oxygen in the central basin of Lake Erie

    Science.gov (United States)

    Soster, Frederick M.; Matisoff, Gerald; Schloesser, Donald W.; Edwards, William J.

    2015-01-01

    Previous studies have indicated that burrow-irrigating infauna can increase sediment oxygen demand (SOD) and impact hypolimnetic oxygen in stratified lakes. We conducted laboratory microcosm experiments and computer simulations with larvae of the burrowing benthic midge Chironomus plumosus to quantify burrow oxygen uptake rates and subsequent contribution to sediment oxygen demand in central Lake Erie. Burrow oxygen uptake and water flow velocities through burrows were measured using oxygen microelectrodes and hot film anemometry, respectively. Burrow oxygen consumption averaged 2.66 × 10− 10 (SE = ± 7.82 × 10− 11) mol O2/burrow/s at 24 °C and 9.64 × 10− 10 (SE = ± 4.86 × 10− 10) mol O2/burrow/s at 15 °C. In sealed microcosm experiments, larvae increased SOD 500% at 24 °C (density = 1508/m2) and 375% at 15 °C (density = 864/m2). To further evaluate effects of densities of C. plumosus burrows on SOD we developed a 3-D transport reaction model of the process. Using experimental data and chironomid abundance data in faunal surveys in 2009 and 2010, we estimated that bioirrigation by a population of 140 larvae/m2 could account for between 2.54 × 10− 11 mol/L/s (model results) and 5.58 × 10− 11 mol/L/s (experimental results) of the average 4.22 × 10− 11 mol/L/s oxygen depletion rate between 1970 and 2003, which could have accounted for 60–132% of the oxygen decline. At present, it appears that the population density of this species may be an important factor in development of hypoxic or anoxic conditions in central Lake Erie.

  16. Modelling the Loktak Lake Basin to Assess Human Impact on Water Resources

    Science.gov (United States)

    Eliza, K.

    2015-12-01

    Loktak Lake is an internationally important, Ramsar designated, fresh water wetland system in the state of Manipur, India. The lake was also listed under Montreux Record on account of the ecological modifications that the lake system has witnessed over time. A characteristic feature of this lake is the extensive occurrence of coalesced, naturally or otherwise, vegetative masses floating over it. A contiguous 40 km2 area of Phumdis, as these vegetative masses are locally referred to, also constitutes the only natural home of the endemic and endangered species of Manipur's brow-antlered deer popularly known as Sangai. Appropriately notified as Keibul Lamjao National Park by Government of India, this natural feature is known to be the world's largest floating park. Water quality and sediment deposition on account of soil erosion in its catchments are some of the emerging concerns along with a reported enhanced frequency and duration of flooding of the shore areas, reduced fish catch within a visibly deteriorated overall natural ecosystem. Disturbances of watershed processes, command area management practices, ineffective as indeed largely absent, waste management practices and management interventions linked to the Loktak Hydroelectric Project are often cited as the principal triggers that are seen to be responsible for the damage. An effective management protocol for the Lake requires a rigorous understanding of its hydrobiology and eco-hydrodynamics. The present study is carried out to establish such a characterization of the various rivers systems draining directly into the Lake using MIKE SHE, MIKE 11 HD and MIKE 11 ECO Lab modelling platforms. Water quality modelling was limited to dissolved oxygen (DO), biological oxygen demand (BOD) and water temperature. Model calibration was done using the available measured water quality data. The derived results were then investigated for causal correlation with anthropogenic influences to assess human impact on water

  17. Evaluating the eco-hydrologic impacts of soil and water conservation in the Jinghe River Basin of Loess Plateau, China, using an eco-hydrologic model

    Science.gov (United States)

    Peng, Hui; Jia, Yangwen; Tague, Christina; Slaughter, Peter

    2016-04-01

    Since the 1950s, soil and water conservation has been widely applied in the Loess Plateau in China. We examine the eco-hydrologic responses to soil and water conservation in the Jinghe River Basin of Loess Plateau in two scales - catchment scale and basin scale, using Regional Hydro-Ecologic Simulation System (RHESSys). In the catchment scale, we apply the model to disentangle the relative roles played by inter-annual variation and longer-term trends in climate drivers and re-growth following reforestation. Our model-based analysis of trends in forest water use highlights the differences in the response of control and reforested catchments to similar declines in annual precipitation in this region over the past decades. Model estimates show that while reforestation does increase vegetation water use, the impacts on streamflow are small relative to the impact of precipitation trends on streamflow, and forest water use. Results also show that the greatest impact of reforestation is likely to be on groundwater recharge but also suggest that evaporation rather than transpiration is a significant contributor to hydrologic change. In the basin scales, we applied the modified model to evaluate the impacts of soil and water conservation measures on streamflow. Results demonstrate that the soil and water conservation decreased annual streamflow by 8% (0.1 billion m3), with the largest decrease occurring in the 2000s. Model estimates also suggest that soil and water conservation engineering has greater impacts than vegetation recovery. This study offers scientific support for soil and water conservation planning and management in this region.

  18. Nutrients levels in paddy soils and flood waters from Tagus-Sado basin: the impact of farming system

    Science.gov (United States)

    Santos, Erika S.; Abreu, Maria Manuela; Magalhães, Maria Clara; Viegas, Wanda; Amâncio, Sara; Cordovil, Cláudia

    2017-04-01

    Application of fertilizers for crops can contribute to nutrients surplus, namely nitrogen, in both groundwater and surface waters resulting in serious environmental problems. The impacts on water quality due to fertilizers are related to land management. In paddy fields using high amounts of water, the nutrient dynamic knowledge is essential to evaluate the impact of farming system. The aims of this study were to evaluate: i)nutrients levels in soils and floodwaters from rice cultivation in Tagus-Sado basin (Portugal); ii)the effect, under controlled conditions, of different irrigation techniques on nutrient enrichment of floodwaters from rice cultivation. Composite samples (n=24) of paddy soils (0-15 cm) and floodwaters were collected, during rice flooding period. In the field, pH and electrical conductivity (EC) were determined in waters. Soil pH, concentrations of Corganic, NPK and nutrients (Ca, Cu, Fe, Mg, Mn, Zn) in soils and floodwaters (nitrites, nitrates, phosphates) were determined. A mesocosm assay was performed in lysimeters with a paddy soil (pH: 5.6; g/kg- Ntotal: 2.0, Pextractable: 0.04, Kextractable: 0.6, Corganic: 35.5) and different irrigation techniques (n=3): a)flood; b)four floods per day (great water renewal); c)flood until rice flowering and then a normal superficial irrigation. Rice cultivation was done by transplant as in the field. Irrigation water come from a well. Same chemical characterization than in field assay were determined in floodwater and irrigation water. In field conditions, paddy soils had values of pH between 5.1 and 8.1 and a great fertility range (g/kg; Ntotal: 0.4‒2.2; Pextractable: 0.01‒0.2; Kextractable: 0.04‒0.7; Corganic: 6.5‒37.9). Total soil concentrations of Cu, Fe, and Zn in soils were in same range and below maximum admissible values for agriculture. Total soil concentrations of Ca, Mg and Mn, showed higher heterogeneity (g/kg; 1.2‒19.3, 7.6‒34.2 and 0.2‒1.5 respectively). Floodwaters presented pH

  19. Impact of the Hoa Binh Dam (Vietnam on water and sediment budgets in the Red River basin and delta

    Directory of Open Access Journals (Sweden)

    D. V. Vu

    2014-01-01

    Full Text Available The Hoa Binh Dam, located on a tributary of the Red River in Vietnam, has a capacity of 9.45 × 109 m3 and was commissioned in December 1988. Although being important for flood prevention, electricity production, and irrigation in northern Vietnam, the Hoa Binh Dam has also highly influenced the suspended sediment distribution in the lower Red River basin, in the delta and in the coastal zone. Its impact was analysed from 50 yr dataset of water discharge and suspended sediment concentration (1960–2010 and the distribution of water and sediment across the nine mouths of the delta was calculated using the MIKE 11 numerical model before and after the dam settlement. Although water discharge at the delta inlet decreased by only 8.8%, the yearly suspended sediment flux dropped, on average from 119 to 43 × 106 t yr−1 at Son Tay near Hanoi, and from 85 to 35 × 106 t yr−1 in the river mouths. Water regulation has led to decreased water discharge in the wet season and increased water discharge in the dry season. Suspended sediment discharge proportionally increased in northern and southern estuaries and decreased through the main and central Ba Lat mouth. Tidal pumping, which causes a net sediment flux from the coast to the estuary at low discharge, is high in the northern delta, as a consequence of the high tidal range (up to 4.5 m in spring tide; diurnal tide. The shifts in the dynamic and characteristics of the turbidity maximum zone in the Cam-Bach Dang estuary are probably the cause of the enhanced sediment deposition in the Haiphong harbor. Along the coast, the reduced sedimentation rates are coincident with the lower sediment delivery that has been observed since the impoundment of the Hoa Binh Dam.

  20. Land cover/use scenario building and its impact on runoff process inside the Iligan river basin

    Science.gov (United States)

    Milano, Alan E.; Suson, Peter D.; Salcedo, Stephanie Mae B.; Blasco, Jennifer G.; Ignacio, Teresa T.

    2016-10-01

    This study aims to assess the results of runoff volume, peak flow and the lag time between peak rainfall and peak river discharge or peak flow when no proper land use management is done and another is when sound land use management is adopted. Hence, two (2) land cover/use scenarios were created. The first scenario is the Projected Land Cover. This scenario was created using a Trend Analysis function from MS Excel derived from the 1973, 1989, 1998, 2008 and 2010 land cover scenarios. The second scenario is the Desired Land Use wherein it makes use of slope as the basis in assigning the different land uses. Specifically, agriculture and built-up were assign to 0-18% slope, 18-30% slope for agroforestry, 30-50% for production forest and >50% for protection forest. Limitedly available LiDAR DEM strips was integrated into the IFSAR DEM to generate a detailed basin model and slope in GIS. The HEC-HMS was used for simulating runoff models. The Projected Land Cover has a higher total runoff volume and peak flow and shorter Lag time as compared to the Desired Land Use scenario in all the four (4) Rainfall Return Period these are 5 years, 25 years, 50 years and 100 years. The latter has twice as much forest vegetation that the projected land cover scenario, it has better forest cover quality and plus the presence of agroforestry. Such condition helps improve soil infiltration and thus reduces runoff volume and peak time. The study shows when land cover conditions are left by itself without any intervention, the impact of flood disaster is more likely to be magnified. The study also shows that flood disaster can be mitigated if the Desired Land Use scenario will be adopted as one of the course of action in flood disaster risk reduction management.

  1. Seasonal snow cover and glacier change impact on water and energy cycle of Central Asia Endorheic Basin

    Science.gov (United States)

    Eisen, Vladimir; Eisen, Elena

    2010-05-01

    High mountains of Central Asia Endorheic Basin (CAEB) hold one of the greatest in the World concentration of snow and glacier ice water resources at mid- latitudes thousands of miles from the oceans providing up to 80% of total river runoff. The total external atmospheric moisture flow over the CAEB comprises approximately 200 billion cubic meters per year. The glaciers of CAEB receive and retain annually up to 10% of moisture transferred over the mountains. However, the area of seasonal snow and glaciers has declining rapidly as result of recent climatic change causes by increase in air temperature and precipitation partitioning between snow and rain, and evaporation fluxes. Based on remote sensing data CAEB glaciers shrunk by 5% between the middle of 1940th and 1970th and 10% during the next 30 years. Evaluation of seasonal snow cover for the same period revealed 20% seasonal snow covered area reduction. During the last thirty years, the duration of snow melt reduced by 30 days from the date of maximum snow cover to the date of its disappearance. Further decrease in seasonal snow cover will be accelerated due to increase of rainfall instead of snowfall in early spring months at high elevations, and consequently a lesser heat expenditure for snowmelt. At high mountains, about 40% of snow ablated during the penultimate 10 days of snow cover. During ablation season, the amount of energy used to melt snow and glacier ice is in the same order as the combination of other components of the heat budget (e.g., heat associated with atmospheric advection, radiation balance and turbulent heat exchange). Heating of the air would have been 3 times higher if snow and glacier ice melt had not occurred. Analysis of shallow ice-cores from high elevation snow/ice fields of CAEB has helped determining the climatic processes controlling hydrological regimes via the changes in global and regional atmospheric circulation patterns and simulates impact of these changes on water and

  2. Using the UKCP09 probabilistic scenarios to model the amplified impact of climate change on river basin sediment yield

    Directory of Open Access Journals (Sweden)

    T. J. Coulthard

    2012-07-01

    Full Text Available Precipitation intensities and the frequency of extreme events are projected to increase under climate change. These rainfall changes will lead to increases in the magnitude and frequency of flood events that will, in turn, affect patterns of erosion and deposition within river basins. These geomorphic changes to river systems may affect flood conveyance, infrastructure resilience, channel pattern, and habitat status, as well as sediment, nutrient and carbon fluxes. Previous research modelling climatic influences on geomorphic changes has been limited by how climate variability and change are represented by downscaling from Global or Regional Climate Models. Furthermore, the non-linearity of the climatic, hydrological and geomorphic systems involved generate large uncertainties at each stage of the modelling process creating an uncertainty "cascade".

    This study integrates state-of-the-art approaches from the climate change and geomorphic communities to address these issues in a probabilistic modelling study of the Swale catchment, UK. The UKCP09 weather generator is used to simulate hourly rainfall for the baseline and climate change scenarios up to 2099, and used to drive the CAESAR landscape evolution model to simulate geomorphic change. Results show that winter rainfall is projected to increase, with larger increases at the extremes. The impact of the increasing rainfall is amplified through the translation into catchment runoff and in turn sediment yield with a 100% increase in catchment mean sediment yield predicted between the baseline and the 2070–2099 High emissions scenario. Significant increases are shown between all climate change scenarios and baseline values. Analysis of extreme events also shows the amplification effect from rainfall to sediment delivery with even greater amplification associated with higher return period events. Furthermore, for the 2070–2099 High emissions scenario, sediment discharges from 50 yr

  3. Using the UKCP09 probabilistic scenarios to model the amplified impact of climate change on drainage basin sediment yield

    Directory of Open Access Journals (Sweden)

    T. J. Coulthard

    2012-11-01

    Full Text Available Precipitation intensities and the frequency of extreme events are projected to increase under climate change. These rainfall changes will lead to increases in the magnitude and frequency of flood events that will, in turn, affect patterns of erosion and deposition within river basins. These geomorphic changes to river systems may affect flood conveyance, infrastructure resilience, channel pattern, and habitat status as well as sediment, nutrient and carbon fluxes. Previous research modelling climatic influences on geomorphic changes has been limited by how climate variability and change are represented by downscaling from global or regional climate models. Furthermore, the non-linearity of the climatic, hydrological and geomorphic systems involved generate large uncertainties at each stage of the modelling process creating an uncertainty "cascade".

    This study integrates state-of-the-art approaches from the climate change and geomorphic communities to address these issues in a probabilistic modelling study of the Swale catchment, UK. The UKCP09 weather generator is used to simulate hourly rainfall for the baseline and climate change scenarios up to 2099, and used to drive the CAESAR landscape evolution model to simulate geomorphic change. Results show that winter rainfall is projected to increase, with larger increases at the extremes. The impact of the increasing rainfall is amplified through the translation into catchment runoff and in turn sediment yield with a 100% increase in catchment mean sediment yield predicted between the baseline and the 2070–2099 High emissions scenario. Significant increases are shown between all climate change scenarios and baseline values. Analysis of extreme events also shows the amplification effect from rainfall to sediment delivery with even greater amplification associated with higher return period events. Furthermore, for the 2070–2099 High emissions scenario, sediment discharges from 50-yr

  4. Numerical Simulation of the Impact of Vegetation Index on the Interannual Variation of Summer Precipitation in the Yellow River Basin

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Two sets of numerical experiments using the coupled National Center for Environmental Prediction General Circulation Model (NCEP/GCM T42L18) and the Simplified Simple Biosphere land surface scheme (SSiB) were carried out to investigate the climate impacts of fractional vegetation cover (FVC)and leaf area index (LAI) on East Asia summer precipitation, especially in the Yellow River Basin (YRB).One set employed prescribed FVC and LAI which have no interannual variations based on the climatology of vegetation distribution; the other with FVC and LAI derived from satellite observations of the International Satellite Land Surface Climate Project (ISLSCP) for 1987 and 1988. The simulations of the two experiments were compared to study the influence of FVC, LAI on summer precipitation interannual variation in the YRB. Compared with observations and the NCEP reanalysis data, the experiment that included both the effects of satellite-derived vegetation indexes and sea surface temperature (SST)produced better seasonal and interannual precipitation variations than the experiment with SST but no interannual variations in FVC and LAI, indicating that better representations of the vegetation index and its interannual variation may be important for climate prediction. The difference between 1987 and 1988indicated that with the increase of FVC and LAI, especially around the YRB, surface albedo decreased,net surface radiation increased, and consequently local evaporation and precipitation intensified. Further more, surface sensible heat flux, surface temperature and its diurnal variation decreased around the YRB in response to more vegetation. The decrease of surface-emitting longwave radiation due to the cooler surface outweighed the decrease of surface solar radiation income with more cloud coverage, thus maintaining the positive anomaly of net surface radiation. Further study indicated that moisture flux variations associated with changes in the general circulation also

  5. Potential ecological impacts of trace metals on aquatic biota within the Upper Little Tennessee River Basin, North Carolina

    Directory of Open Access Journals (Sweden)

    Jerry R. Miller

    2016-06-01

    Full Text Available The Upper Little Tennessee River (ULTR possesses one of the most diverse assemblages of aquatic biota in North America, including the endangered Appalachian elktoe mussel (Alasmidonta raveneliana. Populations of the Appalachian elktoe significantly declined along with other species following an extreme flood in 2004. This paper examines the potential role that four toxic trace metals (Cu, Cr, Ni, and Zn played in the population declines. Dissolved and total-recoverable concentrations of Cr and Ni measured during three flood events were below USEPA and North Carolina freshwater guidelines for potential impacts on aquatic biota, respectively. In contrast, 58% of the samples exceeded NC guideline values for total-recoverable concentrations of Cu and Zn. In general, metal concentrations increased with increasing discharge and suspended sediment concentrations (SSC. These relationships, combined with sequential extraction data from sediments, suggest that most metals were transported in the particulate form and were not readily bioavailable. During individual events, metal concentrations for a given discharge were influenced by a “first flush” hysteresis effect. Rapid increases in metal concentrations during the early stages of an event appear to be related to the entrainment of fine sediment, including particulate Fe to which the metals are sorbed. Instantaneous metal loads calculated for nine tributaries to the ULTR, combined with previously collected data, suggest that the majority of the metals were derived from the erosion of sediment and particulate Fe from subsurface soil horizons developed in bedrock containing sulfidic layers. The erosion was particularly pronounced in tributary basins in poor to moderate ecological condition. While a fraction of the Cu may have been derived from Cu-based pesticides and was periodically elevated above guideline values in river waters, the data in total suggest that toxic trace metals were unlikely to

  6. Anthropogenic phosphorus (P) inputs to a river basin and their impacts on P fluxes along its upstream-downstream continuum

    Science.gov (United States)

    Zhang, Wangshou; Swaney, Dennis; Hong, Bongghi; Howarth, Robert

    2017-04-01

    Phosphorus (P) originating from anthropogenic sources as a pollutant of surface waters has been an environmental issue for decades because of the well-known role of P in eutrophication. Human activities, such as food production and rapid urbanization, have been linked to increased P inputs which are often accompanied by corresponding increases in riverine P export. However, uneven distributions of anthropogenic P inputs along watersheds from the headwaters to downstream reaches can result in significantly different contributions to the riverine P fluxes of a receiving water body. So far, there is still very little scientific understanding of anthropogenic P inputs and their impacts on riverine flux in river reaches along the upstream to downstream continuum. Here, we investigated P budgets in a series of nested watersheds draining into Hongze Lake of China, and developed a simple empirical function to describe the relationship between anthropogenic inputs and riverine TP fluxes. The results indicated that an average of 1.1% of anthropogenic P inputs are exported into rivers, with most of the remainder retained in the watershed landscape over the period studied. Fertilizer application was the main contributor of P loading to the lake (55% of total loads), followed by legacy P stock (30%), food and feed P inputs (12%) and non-food P inputs (4%). From 60% to 89% of the riverine TP loads generated from various locations within this basin were ultimately transported into the receiving lake of the downstream, with an average rate of 1.86 tons P km-1 retaining in the main stem of the inflowing river annually. Our results highlight that in-stream processes can significantly buffer the riverine P loading to the downstream receiving lake. An integrated P management strategy considering the influence of anthropogenic inputs and hydrological interactions is required to assess and optimize P management for protecting fresh waters.

  7. Impact of the Hoa Binh dam (Vietnam) on water and sediment budgets in the Red River basin and delta

    Science.gov (United States)

    Vinh, V. D.; Ouillon, S.; Thanh, T. D.; Chu, L. V.

    2014-10-01

    The Hoa Binh dam (HBD), located on a tributary of the Red River in Vietnam, has a capacity of 9.45 × 109 m3 and was commissioned in December 1988. Although it is important for flood prevention, electricity production and irrigation in northern Vietnam, the Hoa Binh dam has also highly influenced the suspended sediment distribution in the lower Red River basin, in the delta and in the coastal zone. Its impact was analysed from a 50-year data set of water discharge and suspended sediment concentration (1960-2010), and the distribution of water and sediment across the nine mouths of the delta was simulated using the MIKE11 numerical model before and after the dam settlement. Although water discharge at the delta inlet decreased by only 9%, the yearly suspended sediment flux dropped, on average, by 61% at Son Tay near Hanoi (from 119 to 46 × 106 t yr-1). Along the coast, reduced sedimentation rates are coincident with the lower sediment delivery observed since the impoundment of the Hoa Binh dam. Water regulation has led to decreased water discharge in the wet season (-14% in the Red River at Son Tay) and increased water discharge in the dry season (+12% at the same station). The ratios of water and suspended sediment flows, as compared to the total flows in the nine mouths, increased in the northern and southern estuaries and decreased in the central, main Ba Lat mouth. The increasing volume of dredged sediments in the Haiphong harbour is evidence of the silting up of the northern estuary of Cam-Bach Dang. The effect of tidal pumping on enhanced flow occurring in the dry season and resulting from changed water regulation is discussed as a possible cause of the enhanced siltation of the estuary after Hoa Binh dam impoundment.

  8. Climate change impacts under CMIP5 RCP scenarios on water resources of the Kelantan River Basin, Malaysia

    Science.gov (United States)

    Tan, Mou Leong; Ibrahim, Ab Latif; Yusop, Zulkifli; Chua, Vivien P.; Chan, Ngai Weng

    2017-06-01

    This study aims to evaluate the potential impacts of climate change on water resources of the Kelantan River Basin in north-eastern Peninsular Malaysia using the Soil and Water Assessment Tool (SWAT) model. Thirty-six downscaled climate projections from five General Circulation Models (GCMs) under the three Representative Concentration Pathways (RCPs) 2.6, 4.5 and 8.5 scenarios for the periods of 2015-2044 and 2045-2074 were incorporated into the calibrated SWAT model. Differences of these scenarios were calculated by comparing to the 1975-2004 baseline period. Overall, the SWAT model performed well in monthly streamflow simulation, with the Nash-Sutcliffe efficiency values of 0.75 and 0.63 for calibration and validation, respectively. Based on the ensemble of five GCMs, the annual rainfall and maximum temperature are projected to increase by 1.2-8.7% and 0.6-2.1 °C, respectively. This corresponds to the increases in the annual streamflow (14.6-27.2%), evapotranspiration (0.3-2.7%), surface runoff (46.8-90.2%) and water yield (14.2-26.5%) components. The study shows an increase of monthly rainfall during the wet season, and decrease during the dry season. Therefore, the monthly streamflow and surface runoff are likely to increase significantly in November, December and January. In addition, slight decreases in the monthly water yield are found between June and October (1.9-8.9%) during the 2015-2044 period. These findings could act as a scientific reference to develop better climate adaptation strategies.

  9. Impacts of climate variability and extreme events on the terrestrial carbon cycle of the Amazon basin

    Science.gov (United States)

    Harper, A. B.; Cox, P.; Wiltshire, A.; Friedlingstein, P.; Jones, C. D.; Mercado, L.; Groenendijk, M.; Sitch, S.

    2013-12-01

    , biomass, and photosynthesis. Simulated fluxes of net ecosystem exchange, sensible and latent heat fluxes were closest to FLUXNET observations when the model was run with optimized physiological parameters, deep roots, and a relaxed soil moisture stress function. We also compared seasonality of modelled photosynthesis to that implied from measurements of sun-induced chlorophyll fluorescence from the GOSAT satellite, and found good agreement. This gives us confidence in using the model to assess impacts of climate variability. Over the past several decades, the largest fluxes of CO2 from the biosphere to the atmosphere occurred during years of extreme drought: for example during 1987, 1998, and 2010. We analyse the driving factors behind these fluxes to assess climate sensitivity of the Amazon rainforest. The relationship between terrestrial carbon fluxes and sea surface temperatures in the Atlantic and Pacific Oceans are explored as the largest source of the variability, which can help in predicting future sensitivity of the forest.

  10. Application of a technique for scenario prediction of climate change impact on the water balance components of northern river basins

    Directory of Open Access Journals (Sweden)

    Gusev Yeugeniy M.

    2014-09-01

    Full Text Available The scenario forecasting technique for assessing changes of water balance components of the northern river basins due to possible climate change was developed. Three IPCC global emission scenarios corresponding to different possible scenarios for economic, technological, political and demographic development of the human civilization in the 21st century were chosen for generating climate change projections by an ensemble of 16 General Circulation Models with a high spatial resolution. The projections representing increments of monthly values of meteorological characteristics were used for creating 3-hour meteorological time series up to 2063 for the Northern Dvina River basin, which belongs to the pan-Arctic basin and locates at the north of the European part of Russia. The obtained time series were applied as forcing data to drive the land surface model SWAP to simulate possible changes in the water balance components due to different scenarios of climate change for the Northern Dvina River basin

  11. Strategic planning for instream flow restoration: a case study of potential climate change impacts in the central Columbia River basin.

    Science.gov (United States)

    Donley, Erin E; Naiman, Robert J; Marineau, Mathieu D

    2012-10-01

    We provide a case study prioritizing instream flow restoration activities by sub-basin according to the habitat needs of Endangered Species Act (ESA)-listed salmonids relative to climate change in the central Columbia River basin in Washington State (USA). The objective is to employ scenario analysis to inform and improve existing instream flow restoration projects. We assess the sensitivity of late summer (July, August, and September) flows to the following scenario simulations - singly or in combination: climate change, changes in the quantity of water used for irrigation and possible changes to existing water resource policy. Flows for four sub-basins were modeled using the Water Evaluation and Planning system (WEAP) under historical and projected conditions of 2020 and 2040 for each scenario. Results indicate that Yakima will be the most flow-limited sub-basin with average reductions in streamflow of 41% under climate conditions of 2020 and 56% under 2040 conditions; 1.3-2.5 times greater than those of other sub-basins. In addition, irrigation plays a key role in the hydrology of the Yakima sub-basin - with flow reductions ranging from 78% to 90% under severe to extreme (i.e., 20-40%) increases in agricultural water use (2.0-4.4 times the reductions in the other sub-basins). The Yakima and Okanogan sub-basins are the most responsive to simulations of flow-bolstering policy change (providing salmon with first priority water allocation and at biologically relevant flows), as demonstrated by 91-100% target flows attained. The Wenatchee and Methow sub-basins do not exhibit similar responsiveness to simulated policy changes. Considering climate change only, we conclude that flow restoration should be prioritized first in the Yakima and Wenatchee sub-basins, and second in the Okanogan and Methow. Considering both climate change and possible policy changes, we recommend that the Yakima sub-basin receive the highest priority for flow restoration activities to sustain

  12. THE DEGREE OF SILTING AND THE IMPACT ON ALLUVIAL DEPOSITS IN THE RIVER BEDS OF BISTRIŢA RIVER BASIN

    OpenAIRE

    COJOC MARIA GEANINA; ROMANESCU GH.; TIRNOVAN ALINA

    2014-01-01

    Since 1960 the Bistriţa River basin came under the profound influence of anthropic incidence. This river basin represents a pattern of use for hydropower potential: reservoirs (9); channels (61 km); water dams; transfers of flows; protection structures works for banks and slopes; relocation of human settlements (13 villages); gravel pits; galleries; viaducts; communication paths, etc. Bistriţa River development has led to significant changes in the structure of the hydrological regime, throug...

  13. Modeling the impact of the nitrate contamination on groundwater at the groundwater body scale : The Geer basin case study (Invited)

    Science.gov (United States)

    Brouyere, S.; Orban, P.; Hérivaux, C.

    2009-12-01

    In the next decades, groundwater managers will have to face regional degradation of the quantity and quality of groundwater under pressure of land-use and socio-economic changes. In this context, the objectives of the European Water Framework Directive require that groundwater be managed at the scale of the groundwater body, taking into account not only all components of the water cycle but also the socio-economic impact of these changes. One of the main challenges remains to develop robust and efficient numerical modeling applications at such a scale and to couple them with economic models, as a support for decision support in groundwater management. An integrated approach between hydrogeologists and economists has been developed by coupling the hydrogeological model SUFT3D and a cost-benefit economic analysis to study the impact of agricultural practices on groundwater quality and to design cost-effective mitigation measures to decrease nitrate pressure on groundwater so as to ensure the highest benefit to the society. A new modeling technique, the ‘Hybrid Finite Element Mixing Cell’ approach has been developed for large scale modeling purposes. The principle of this method is to fully couple different mathematical and numerical approaches to solve groundwater flow and solute transport problems. The mathematical and numerical approaches proposed allows an adaptation to the level of local hydrogeological knowledge and the amount of available data. In combination with long time series of nitrate concentrations and tritium data, the regional scale modelling approach has been used to develop a 3D spatially distributed groundwater flow and solute transport model for the Geer basin (Belgium) of about 480 km2. The model is able to reproduce the spatial patterns of nitrate concentrations together nitrate trends with time. The model has then been used to predict the future evolution of nitrate trends for two types of scenarios: (i) a “business as usual scenario

  14. Stratigraphy, Sequence, and Crater Populations of Lunar Impact Basins from Lunar Orbiter Laser Altimeter (LOLA) Data: Implications for the Late Heavy Bombardment

    Science.gov (United States)

    Fassett, C. I.; Head, J. W.; Kadish, S. J.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2012-01-01

    New measurements of the topography of the Moon from the Lunar Orbiter Laser Altimeter (LOLA)[1] provide an excellent base-map for analyzing the large crater population (D.20 km)of the lunar surface [2, 3]. We have recently used this data to calculate crater size-frequency distributions (CSFD) for 30 lunar impact basins, which have implications for their stratigraphy and sequence. These data provide an avenue for assessing the timing of the transitions between distinct crater populations characteristic of ancient and young lunar terrains, which has been linked to the late heavy bombardment (LHB). We also use LOLA data to re-examine relative stratigraphic relationships between key lunar basins.

  15. Land use and climate change impacts on the hydrology of the upper Mara River Basin, Kenya: results of a modeling study to support better resource management

    Directory of Open Access Journals (Sweden)

    L. M. Mango

    2011-07-01

    Full Text Available Some of the most valued natural and cultural landscapes on Earth lie in river basins that are poorly gauged and have incomplete historical climate and runoff records. The Mara River Basin of East Africa is such a basin. It hosts the internationally renowned Mara-Serengeti landscape as well as a rich mixture of indigenous cultures. The Mara River is the sole source of surface water to the landscape during the dry season and periods of drought. During recent years, the flow of the Mara River has become increasingly erratic, especially in the upper reaches, and resource managers are hampered by a lack of understanding of the relative influence of different sources of flow alteration. Uncertainties about the impacts of future climate change compound the challenges. We applied the Soil Water Assessment Tool (SWAT to investigate the response of the headwater hydrology of the Mara River to scenarios of continued land use change and projected climate change. Under the data-scarce conditions of the basin, model performance was improved using satellite-based estimated rainfall data, which may also improve the usefulness of runoff models in other parts of East Africa. The results of the analysis indicate that any further conversion of forests to agriculture and grassland in the basin headwaters is likely to reduce dry season flows and increase peak flows, leading to greater water scarcity at critical times of the year and exacerbating erosion on hillslopes. Most climate change projections for the region call for modest and seasonally variable increases in precipitation (5–10 % accompanied by increases in temperature (2.5–3.5 °C. Simulated runoff responses to climate change scenarios were non-linear and suggest the basin is highly vulnerable under low (−3 % and high (+25 % extremes of projected precipitation changes, but under median projections (+7 % there is little impact on annual water yields or mean discharge. Modest increases in precipitation

  16. Land use and climate change impacts on the hydrology of the upper Mara River Basin, Kenya: results of a modeling study to support better resource management

    Science.gov (United States)

    Mango, L. M.; Melesse, A. M.; McClain, M. E.; Gann, D.; Setegn, S. G.

    2011-07-01

    Some of the most valued natural and cultural landscapes on Earth lie in river basins that are poorly gauged and have incomplete historical climate and runoff records. The Mara River Basin of East Africa is such a basin. It hosts the internationally renowned Mara-Serengeti landscape as well as a rich mixture of indigenous cultures. The Mara River is the sole source of surface water to the landscape during the dry season and periods of drought. During recent years, the flow of the Mara River has become increasingly erratic, especially in the upper reaches, and resource managers are hampered by a lack of understanding of the relative influence of different sources of flow alteration. Uncertainties about the impacts of future climate change compound the challenges. We applied the Soil Water Assessment Tool (SWAT) to investigate the response of the headwater hydrology of the Mara River to scenarios of continued land use change and projected climate change. Under the data-scarce conditions of the basin, model performance was improved using satellite-based estimated rainfall data, which may also improve the usefulness of runoff models in other parts of East Africa. The results of the analysis indicate that any further conversion of forests to agriculture and grassland in the basin headwaters is likely to reduce dry season flows and increase peak flows, leading to greater water scarcity at critical times of the year and exacerbating erosion on hillslopes. Most climate change projections for the region call for modest and seasonally variable increases in precipitation (5-10 %) accompanied by increases in temperature (2.5-3.5 °C). Simulated runoff responses to climate change scenarios were non-linear and suggest the basin is highly vulnerable under low (-3 %) and high (+25 %) extremes of projected precipitation changes, but under median projections (+7 %) there is little impact on annual water yields or mean discharge. Modest increases in precipitation are partitioned

  17. Water Resource Management in Dry Zonal Paddy Cultivation in Mahaweli River Basin, Sri Lanka: An Analysis of Spatial and Temporal Climate Change Impacts and Traditional Knowledge

    Directory of Open Access Journals (Sweden)

    Sisira S. Withanachchi

    2014-11-01

    Full Text Available Lack of attention to spatial and temporal cross-scale dynamics and effects could be understood as one of the lacunas in scholarship on river basin management. Within the water-climate-food-energy nexus, an integrated and inclusive approach that recognizes traditional knowledge about and experiences of climate change and water resource management can provide crucial assistance in confronting problems in megaprojects and multipurpose river basin management projects. The Mahaweli Development Program (MDP, a megaproject and multipurpose river basin management project, is demonstrating substantial failures with regards to the spatial and temporal impacts of climate change and socioeconomic demands for water allocation and distribution for paddy cultivation in the dry zone area, which was one of the driving goals of the project at the initial stage. This interdisciplinary study explores how spatial and temporal climatic changes and uncertainty in weather conditions impact paddy cultivation in dry zonal areas with competing stakeholders’ interest in the Mahaweli River Basin. In the framework of embedded design in the mixed methods research approach, qualitative data is the primary source while quantitative analyses are used as supportive data. The key findings from the research analysis are as follows: close and in-depth consideration of spatial and temporal changes in climate systems and paddy farmers’ socioeconomic demands altered by seasonal changes are important factors. These factors should be considered in the future modification of water allocation, application of distribution technologies, and decision-making with regards to water resource management in the dry zonal paddy cultivation of Sri Lanka.

  18. Impacts of development type and spatial pattern on the hydrologic cycle of headwater basins in urbanized Baltimore County, MD

    Science.gov (United States)

    Barnes, M.; Welty, C.; Miller, A. J.

    2016-12-01

    We compare the effects of urban development type and spatial pattern on the hydrology of six small headwater sub-basins of the Gwynns Falls watershed of Baltimore County, Maryland utilizing a 3-dimensional coupled groundwater-surface water-land atmosphere model (ParFlow.CLM). The sub-basins range in size from 0.2 - 0.6 sq km, across a spectrum of older heavily urbanized development to rural residential. The topography and land cover of each model domain is defined using high-resolution LiDAR topography and ortho-imagery. Simulations were conducted at an hourly time-step for calendar years 2012-2015 using a 10-m terrain-following horizontal grid with variable dz (0.1 m to 8 m). Trends in regional observed groundwater levels are well-captured by normalized model subsurface storage, and Nash-Sutcliffe efficiency for daily runoff at instrumented sub-basin outlets is satisfactory. Comparing results across the basins, differences in development type and pattern give rise to complex spatial and temporal trends in the water budget. Higher cumulative runoff is observed with increasing impervious cover across the six basins, but decreased ET reduces withdrawals from subsurface storage. Overall, a negative correlation (r^2 > 0.95) is observed across sub-basins between impervious cover and net subsurface storage variability. Spatially, the development footprint controls where recharge and ET occur in the unsaturated zone. Mean temporal variability in modeled pressure head is most responsive to development pattern in near-surface layers, but transitions to topographic control at depth. Net reduction in subsurface storage variability alters the magnitude of seasonal basin responses to precipitation and ET.

  19. Dilution correction equation revisited: The impact of stream slope, relief ratio and area size of basin on geochemical anomalies

    Science.gov (United States)

    Shahrestani, Shahed; Mokhtari, Ahmad Reza

    2017-04-01

    Stream sediment sampling is a well-known technique used to discover the geochemical anomalies in regional exploration activities. In an upstream catchment basin of stream sediment sample, the geochemical signals originating from probable mineralization could be diluted due to mixing with the weathering material coming from the non-anomalous sources. Hawkes's equation (1976) was an attempt to overcome the problem in which the area size of catchment basin was used to remove dilution from geochemical anomalies. However, the metal content of a stream sediment sample could be linked to several geomorphological, sedimentological, climatic and geological factors. The area size is not itself a comprehensive representative of dilution taking place in a catchment basin. The aim of the present study was to consider a number of geomorphological factors affecting the sediment supply, transportation processes, storage and in general, the geochemistry of stream sediments and their incorporation in the dilution correction procedure. This was organized through employing the concept of sediment yield and sediment delivery ratio and linking such characteristics to the dilution phenomenon in a catchment basin. Main stream slope (MSS), relief ratio (RR) and area size (Aa) of catchment basin were selected as the important proxies (PSDRa) for sediment delivery ratio and then entered to the Hawkes's equation. Then, Hawkes's and new equations were applied on the stream sediment dataset collected from Takhte-Soleyman district, west of Iran for Au, As and Sb values. A number of large and small gold, antimony and arsenic mineral occurrences were used to evaluate the results. Anomaly maps based on the new equations displayed improvement in anomaly delineation taking the spatial distribution of mineral deposits into account and could present new catchment basins containing known mineralization as the anomaly class, especially in the case of Au and As. Four catchment basins having Au and As

  20. The Cretaceous-Paleogene boundary deposit in the Gulf of Mexico: Large-scale oceanic basin response to the Chicxulub impact

    Science.gov (United States)

    Sanford, Jason C.; Snedden, John W.; Gulick, Sean P. S.

    2016-03-01

    Hydrocarbon exploration in the last decade has yielded sufficient data to evaluate the Gulf of Mexico basin response to the Chicxulub asteroid impact. Given its passive marine setting and proximity to the impact structure on the Yucatán Peninsula, the gulf is the premier locale in which to study the near-field geologic effect of a bolide impact. We mapped a thick (decimeter- to hectometer-scale) deposit of carbonate debris at the Cretaceous-Paleogene boundary that is ubiquitous in the gulf and readily identifiable on borehole and seismic data. We interpret deposits seen in seismic and borehole data in the deepwater gulf to be predominately muddy debrites with minor turbidites based on cores in the southeastern gulf. Mapping of the deposit in the northern Gulf of Mexico reveals that the impact redistributed roughly 1.05 × 105 km3 of sediment therein and over 1.98 × 105 km3 gulfwide. Deposit distribution suggests that the majority of sediment derived from coastal and shallow-water environments throughout the gulf via seismic and megatsunamic processes initiated by the impact. The Texas shelf and northern margin of the Florida Platform were significant sources of sediment, while the central and southern Florida Platform underwent more localized platform collapse. The crustal structure of the ancestral gulf influenced postimpact deposition both directly and indirectly through its control on salt distribution in the Louann Salt Basin. Nevertheless, impact-generated deposition overwhelmed virtually all topography and depositional systems at the start of the Cenozoic, blanketing the gulf with carbonate debris within days.

  1. On the impact of spatial heterogeneous permeability distributions on the development of free convection cells in the Perth Basin, Australia.

    Science.gov (United States)

    Niederau, Jan; Ebigbo, Anozie; Freitag, Sebastian; Marquart, Gabriele; Clauser, Christoph

    2014-05-01

    Recent increase in exploration of the geothermal energy potential of the Perth Metropolitan Area (PMA) results in the need for reliable and robust reservoir models in order to explore rock properties and temperature distributions in the subsurface, where free convection in the main reservoir (Yarragadee Aquifer) is likely to occur [1]. While the structure of the Perth Basin has been refined recently, the heterogeneity and spatial complexity of permeability was up till now mainly neglected. An integrated, three dimensional tectonostratigraphic model of the PMA is constructed, using the modeling software '3D GeoModeller' and data of numerous artesian and petroleum wells. Comprising the region around the city of Perth, the model covers an area of about 5000 km2 up to a depth of 4.5 km, with focus on adequate representation of the main reservoir. We further construct a numerical model for fluid flow and heat transport in the Yarragadee Aquifer. Porosity distributions are deduced from well logs and linked to permeability by a calibrated correlation, based on a fractal approach. Three different cases are simulated using the FD code SHEMAT-Suite, in order to assess the influence of spatial heterogeneity of porosity and permeability on the development of free convection cells. constant porosity and permeability for the entire aquifer porosity and permeability decreasing with depth, thus reflecting compaction a conditional random permeability field within prescribed limits and for given correlation length In order to improve understanding of model correctness, as well as identification and comparison of convection cells in different simulations, we are developing a specialized visualization tool tailored to this purpose. The three different scenarios show distinctions in the distribution of convection cells. Where the Yarragadee Aquifer is in contact with overlying aquifers, regions of downflow develop. These in turn have a strong impact on the regional flow field and

  2. Climate change impact on hydroclimate regimes and extremes over Andean basins in the central-southern Chile

    Science.gov (United States)

    Bozkurt, Deniz; Rojas, Maisa; Valdivieso, Jonás; Falvey, Mark

    2015-04-01

    We have assessed the impact of projected increases in temperature and decreased precipitation on variability and potential changes in hydroclimate regimes and extremes over Andean basins in the central-southern Chile (~30-40S). The altitude of the southern Andes in the study area has an average altitude of 5000 m in the north that decreases to 3000 m at the southern edge. Climatically the region has a Mediterranean-like climate with mainly winter precipitation that gradually increases southwards, from around 300 mm/yr to 1000 mm/yr. The region is home to most of the population in Chile (~10 mil. inhabitants), it has fertile and productive agriculture land, as well as hydro-electrical power plants. During the 20th Century the region has experienced a decreasing precipitation trend imbedded in important interannual and decadal scale variability. We have used gridded observed daily precipitation and temperatures to drive and validate the VIC macro-scale model over the region of interest at 0.25 x 0.25 degree resolution. Historical (1960-2005) and projected (RCP8.5, 2006-2099) daily precipitation and temperatures from 28 CMIP5 models are adjusted via a transfer function based on the gridded observed daily precipitation and temperature data. Adjusted time series are then used to drive the VIC model in order to present climate change projections. The hydrological model simulations foresee that drying is robust in the models and total annual runoff will decrease in the future (40-45% by the end of the century). Center timing of runoff tends to shift to earlier days (3-5 weeks by the end of the century). In some areas over the Andes winter runoff is projected to increase due to upward movement of zero isotherm. Moreover, reductions in the amount of snowpack and accelerated snowmelt lead to more pronounced increase in winter evapotranspiration over the same areas. The simulated 12-months Standardized Runoff Index (SRI) clearly shows severe persistent hydrological droughts

  3. Impact of cable bacteria on sedimentary iron and manganese dynamics in a seasonally-hypoxic marine basin

    Science.gov (United States)

    Sulu-Gambari, Fatimah; Seitaj, Dorina; Behrends, Thilo; Banerjee, Dipanjan; Meysman, Filip J. R.; Slomp, Caroline P.

    2016-11-01

    Cable bacteria have recently been identified in various sedimentary marine settings worldwide. These filamentous microbes mediate electrogenic sulphur oxidation (e-SOx) over centimetre-scale distances, leading to a distinct separation of oxygen- and sulphide-bearing sediment zones. Here we present results of a year-long monthly assessment of the impact of cable bacteria on sedimentary Fe and Mn dynamics at three sites located along a water depth gradient in a seasonally-hypoxic coastal marine lake (Grevelingen, The Netherlands). Fluorescence In Situ Hybridisation (FISH) shows the presence of cable bacteria at two sites in spring. Micro-sensor profiling (O2, pH, H2S) and pore water profiles of dissolved Mn, Fe2+, Ca2+ and SO42- reveal the geochemical signature of e-SOx at these sites, i.e. the development of a broad suboxic zone, characterised by a low pH and acidic dissolution of Ca/Mn carbonates and Fe sulphides. Cable bacteria activity, as reflected by dissolution of FeS in spring, was highest at the deepest and most hypoxic site. In spring, dissolved Mn and Fe2+ released at depth due to e-SOx diffused upwards and was sequestered as Mn- and Fe-(oxyhydr)oxides near the sediment surface, with Mn oxides acting as an oxidant for part of the upward diffusing Fe2+. Strikingly, the thickness of the Fe-(oxyhydr)oxide-bearing surface layer of the sediment was greatest at the most hypoxic site, emphasising the key role of cable bacteria in creating oxidised surface sediments. X-ray absorption fine structure analyses confirm the seasonality in Fe-(oxyhydr)oxide formation and reveal that the sediment Mn oxides were of biogenic (birnessite) and abiotic (hausmannite) origin. Upon the onset of hypoxia in early summer, the sediment Fe-(oxyhydr)oxides were mostly converted to Fe-sulphides but the Mn oxides dissolved and the Mn was lost to the overlying water. After summer hypoxia, Beggiatoaceae mats colonised the sediment with little further change in sediment geochemistry. Our

  4. Climate change and environmental water reallocation in the Murray-Darling Basin: Impacts on flows, diversions and economic returns to irrigation

    Science.gov (United States)

    Kirby, J. M.; Connor, J.; Ahmad, M. D.; Gao, L.; Mainuddin, M.

    2014-10-01

    Increasing river environment degradation from historical growth in withdrawal is leading to reallocation of water from irrigation in many basins. We examine how potential reduction in irrigation allocations under a newly enacted environmental water plan for the Murray Darling Basin in Australia, in combination with projected climate change, impact on flows, diversions and the economic returns to irrigation. We use an integrated hydrology-economics model capable of simulating the year-to-year variability of flows, diversions, and economic returns to model three levels of reallocation (2400, 2750 and 3200 GL) under the historical climate, and under a dry, a median and a wet climate change projection. Previous assessments of the reallocation plan do not address climate change impacts, nor the impact of year to year variability in flows on economic returns. The broad results of this analysis are that estimated river flows and diversions are more sensitive to the range of climate change projections than to the range of diversion reallocation scenarios considered. The projected median climate change more or less removes from flows the gains to the environment resulting from reallocation. Reallocations only in combination with no climate change, or climate change at the wetter end of the range of projections, will lead to flows greater than those experienced under the water management regime prior to reallocation. The reduction in economic returns to irrigation is less than the reduction in water available for irrigation: a 25% reduction in the annual average water availability is estimated to reduce the annual average gross value of irrigated agricultural production by about 10%. This is consistent with expectation of economic theory (since more marginal activities are reduced first) and also with observations of reduced water availability and returns in the recent drought in the Murray-Darling Basin. Irrigation returns vary less across the range of climate change

  5. Understanding Droughts and their Agricultural Impact in North America at the Basin Scale through the Development of Satellite Based Drought Indicators

    Science.gov (United States)

    Munoz Hernandez, A.; Lawford, R. G.

    2012-12-01

    Drought is a major constraint severely affecting numerous agricultural regions in North America. Decision makers need timely information on the existence of a drought as well as its intensity, frequency, likely duration, and economic and social effects in order to implement adaptation strategies and minimize its impacts. Countries like Mexico and Canada face a challenge associated with the lack of consistent and reliable in-situ data that allows the computation of drought indicators at resolutions that effectively supports decision makers at the watershed scale. This study focuses on (1) the development of near-real time drought indicators at high resolution utilizing various satellite data for use in improving adaptation plans and mitigation actions at the basin level; (2) the quantification of the relationships between current and historical droughts and their agricultural impacts by evaluating thresholds for drought impacts; and (3) the assessment of the effects of existing water policies, economic subsidies, and infrastructure that affect the vulnerability of a particular region to the economic impacts of a drought. A pilot study area located in Northwest Mexico and known as the Rio Yaqui Basin was selected for this study in order to make comparisons between the satellite based indicators derived from currently available satellite products to provide an assessment of the quality of the products generated. The Rio Yaqui Basin, also referred to as the "bread basket" of Mexico, is situated in an arid to semi-arid region where highly sophisticated irrigation systems have been implemented to support extensive agriculture. Although for many years the irrigation systems acted as a safety net for the farmers, recent droughts have significantly impacted agricultural output, affected thousands of people, and increase the dependence on groundwater. The drought indices generated are used in conjunction with a decision-support model to provide information on drought impacts

  6. GIS and remote sensing techniques for the assessment of land use changes impact on flood hydrology: the case study of Yialias Basin in Cyprus

    Directory of Open Access Journals (Sweden)

    D. D. Alexakis

    2013-09-01

    Full Text Available Flooding is one of the most common natural disasters worldwide, leading to economic losses and loss of human lives. This paper highlights the hydrological effects of multi-temporal land use changes in flood hazard within the Yialias catchment area, located in central Cyprus. Calibrated hydrological and hydraulic models were used to describe the hydrological processes and internal basin dynamics of the three major sub-basins, in order to study the diachronic effects of land use changes. For the implementation of the hydrological model, land use, soil and hydrometeorological data were incorporated. The climatic and stream flow data were derived from rain and flow gauge stations located in the wider area of the watershed basin. In addition, the land use and soil data were extracted after the application of object oriented nearest neighbor algorithms of ASTER satellite images. Subsequently, the CA-Markov chain analysis was implemented to predict the 2020 Land use/Land cover (LULC map and incorporate it to the hydrological impact assessment. The results denoted the increase of runoff in the catchment area due to the recorded extensive urban sprawl phenomenon of the last decade.

  7. Impact of Urbanization on Stormwater Runoff from a Small Urban Catchment: Gdańsk Małomiejska Basin Case Study

    Science.gov (United States)

    Olechnowicz, Borys; Weinerowska-Bords, Katarzyna

    2014-12-01

    This paper deals with the impact of different forms of urbanization on the basin outflow. The influence of changes in land cover/use, drainage system development, reservoirs, and alternative ways of stormwater management (green roofs, permeable pavements) on basin runoff was presented in the case of a small urban basin in Gdansk (Poland). Seven variants of area development (in the period of 2000-2012) - three historical and four hypothetical - were analyzed. In each case, runoff calculations for three rainfall scenarios were carried out by means of the Hydrologic Modeling System designed by Hydrologic Engineering Center of the U.S. Army Corps of Engineers (HEC-HMS). The Soil Conservation Service (SCS) Curve Number (CN) method was used for calculations of effective rainfall, the kinematic wave model for those of overland flow, and the Muskingum-Cunge model for those of channel routing. The calculations indicated that urban development had resulted in increased peak discharge and runoff volume and in decreased peak time. On the other hand, a significant reduction in peak values was observed for a relatively small decrease in the normal storage level (NSL) in reservoirs or when green roofs on commercial centers were present. The study confirmed a significant increase in runoff as a result of urbanization and a considerable runoff reduction by simple alternative ways of stormwater management.

  8. GIS and remote sensing techniques for the assessment of land use changes impact on flood hydrology: the case study of Yialias Basin in Cyprus

    Science.gov (United States)

    Alexakis, D. D.; Gryllakis, M. G.; Koutroulis, A. G.; Agapiou, A.; Themistocleous, K.; Tsanis, I. K.; Michaelides, S.; Pashiardis, S.; Demetriou, C.; Aristeidou, K.; Retalis, A.; Tymvios, F.; Hadjimitsis, D. G.

    2013-09-01

    Flooding is one of the most common natural disasters worldwide, leading to economic losses and loss of human lives. This paper highlights the hydrological effects of multi-temporal land use changes in flood hazard within the Yialias catchment area, located in central Cyprus. Calibrated hydrological and hydraulic models were used to describe the hydrological processes and internal basin dynamics of the three major sub-basins, in order to study the diachronic effects of land use changes. For the implementation of the hydrological model, land use, soil and hydrometeorological data were incorporated. The climatic and stream flow data were derived from rain and flow gauge stations located in the wider area of the watershed basin. In addition, the land use and soil data were extracted after the application of object oriented nearest neighbor algorithms of ASTER satellite images. Subsequently, the CA-Markov chain analysis was implemented to predict the 2020 Land use/Land cover (LULC) map and incorporate it to the hydrological impact assessment. The results denoted the increase of runoff in the catchment area due to the recorded extensive urban sprawl phenomenon of the last decade.

  9. Using SWAT and Fuzzy TOPSIS to Assess the Impact of Climate Change in the Headwaters of the Segura River Basin (SE Spain

    Directory of Open Access Journals (Sweden)

    Javier Senent-Aparicio

    2017-02-01

    Full Text Available The Segura River Basin is one of the most water-stressed basins in Mediterranean Europe. If we add to the actual situation that most climate change projections forecast important decreases in water resource availability in the Mediterranean region, the situation will become totally unsustainable. This study assessed the impact of climate change in the headwaters of the Segura River Basin using the Soil and Water Assessment Tool (SWAT with bias-corrected precipitation and temperature data from two Regional Climate Models (RCMs for the medium term (2041–2070 and the long term (2071–2100 under two emission scenarios (RCP4.5 and RCP8.5. Bias correction was performed using the distribution mapping approach. The fuzzy TOPSIS technique was applied to rank a set of nine GCM–RCM combinations, choosing the climate models with a higher relative closeness. The study results show that the SWAT performed satisfactorily for both calibration (NSE = 0.80 and validation (NSE = 0.77 periods. Comparing the long-term and baseline (1971–2000 periods, precipitation showed a negative trend between 6% and 32%, whereas projected annual mean temperatures demonstrated an estimated increase of 1.5–3.3 °C. Water resources were estimated to experience a decrease of 2%–54%. These findings provide local water management authorities with very useful information in the face of climate change.

  10. Heat or Cold: Which One Exerts Greater Deleterious Effects on Health in a Basin Climate City? Impact of Ambient Temperature on Mortality in Chengdu, China.

    Science.gov (United States)

    Cui, Yan; Yin, Fei; Deng, Ying; Volinn, Ernest; Chen, Fei; Ji, Kui; Zeng, Jing; Zhao, Xing; Li, Xiaosong

    2016-12-10

    Background: Although studies from many countries have estimated the impact of ambient temperature on mortality, few have compared the relative impacts of heat and cold on health, especially in basin climate cities. We aimed to quantify the impact of ambient temperature on mortality, and to compare the contributions of heat and cold in a large basin climate city, i.e., Chengdu (Sichuan Province, China); Methods: We estimated the temperature-mortality association with a distributed lag non-linear model (DLNM) with a maximum lag-time of 21 days while controlling for long time trends and day of week. We calculated the mortality risk attributable to heat and cold, which were defined as temperatures above and below an "optimum temperature" that corresponded to the point of minimum mortality. In addition, we explored effects of individual characteristics; Results: The analysis provides estimates of the overall mortality burden attributable to temperature, and then computes the components attributable to heat and cold. Overall, the total fraction of deaths caused by both heat and cold was 10.93% (95%CI: 7.99%-13.65%). Taken separately, cold was responsible for most of the burden (estimate 9.96%, 95%CI: 6.90%-12.81%), while the fraction attributable to heat was relatively small (estimate 0.97%, 95%CI: 0.46%-2.35%). The attributable risk (AR) of respiratory diseases was higher (19.69%, 95%CI: 14.45%-24.24%) than that of cardiovascular diseases (11.40%, 95%CI: 6.29%-16.01%); Conclusions: In Chengdu, temperature was responsible for a substantial fraction of deaths, with cold responsible for a higher proportion of deaths than heat. Respiratory diseases exert a larger effect on death than other diseases especially on cold days. There is potential to reduce respiratory-associated mortality especially among the aged population in basin climate cities when the temperature deviates beneath the optimum. The result may help to comprehensively assess the impact of ambient temperature

  11. Waste-water impacts on groundwater: Cl/Br ratios and implications for arsenic pollution of groundwater in the Bengal Basin and Red River Basin, Vietnam.

    Science.gov (United States)

    McArthur, J M; Sikdar, P K; Hoque, M A; Ghosal, U

    2012-10-15

    Across West Bengal and Bangladesh, concentrations of Cl in much groundwater exceed the natural, upper limit of 10 mg/L. The Cl/Br mass ratios in groundwaters range up to 2500 and scatter along mixing lines between waste-water and dilute groundwater, with many falling near the mean end-member value for waste-water of 1561 at 126 mg/L Cl. Values of Cl/Br exceed the seawater ratio of 288 in uncommon NO(3)-bearing groundwaters, and in those containing measurable amounts of salt-corrected SO(4) (SO(4) corrected for marine salt). The data show that shallow groundwater tapped by tube-wells in the Bengal Basin has been widely contaminated by waste-water derived from pit latrines, septic tanks, and other methods of sanitary disposal, although reducing conditions in the aquifers have removed most evidence of NO(3) additions from these sources, and much evidence of their additions of SO(4). In groundwaters from wells in palaeo-channel settings, end-member modelling shows that >25% of wells yield water that comprises ≥10% of waste-water. In palaeo-interfluvial settings, only wells at the margins of the palaeo-interfluvial sequence contain detectable waste water. Settings are identifiable by well-colour survey, owner information, water composition, and drilling. Values of Cl/Br and faecal coliform counts are both inversely related to concentrations of pollutant As in groundwater, suggesting that waste-water contributions to groundwater in the near-field of septic-tanks and pit-latrines (within 30 m) suppress the mechanism of As-pollution and lessen the prevalence and severity of As pollution. In the far-field of such sources, organic matter in waste-water may increase groundwater pollution by As. Copyright © 2012. Published by Elsevier B.V.

  12. Using High Resolution Satellite Precipitation fields to Assess the Impacts of Climate Change on the Santa Cruz and San Pedro River Basins

    Science.gov (United States)

    Robles-Morua, A.; Vivoni, E.; Rivera-Fernandez, E. R.; Dominguez, F.; Meixner, T.

    2013-05-01

    Hydrologic modeling using high spatiotemporal resolution satellite precipitation products in the southwestern United States and northwest Mexico is important given the sparse nature of available rain gauges. In addition, the bimodal distribution of annual precipitation also presents a challenge as differential climate impacts during the winter and summer seasons are not currently well understood. In this work, we focus on hydrological comparisons using rainfall forcing from a satellite-based product, downscaled GCM precipitation estimates and available ground observations. The simulations are being conducted in the Santa Cruz and San Pedro river basins along the Arizona-Sonora border at high spatiotemporal resolutions (~100 m and ~1 hour). We use a distributed hydrologic model, known as the TIN-based Real-time Integrated Basin Simulator (tRIBS), to generate simulated hydrological fields under historical (1991-2000) and climate change (2031-2040) scenarios obtained from an application of the Weather Research and Forecast (WRF) model. Using the distributed model, we transform the meteorological scenarios at 10-km, hourly resolution into predictions of the annual water budget, seasonal land surface fluxes and individual hydrographs of flood and recharge events. We compare the model outputs and rainfall fields of the WRF products against the forcing from the North American Land Data Assimilation System (NLDAS) and available ground observations from the National Climatic Data Center (NCDC) and Arizona Meteorological Network (AZMET). For this contribution, we selected two full years in the historical period and in the future scenario that represent wet and dry conditions for each decade. Given the size of the two basins, we rely on a high performance computing platform and a parallel domain discretization with higher resolutions maintained at experimental catchments in each river basin. Model simulations utilize best-available data across the Arizona-Sonora border on

  13. Impact of recent land use and climate changes on sediment and pollutant redistribution in small catchments within the Seim River Basin (Kursk Region, European Russia)

    Science.gov (United States)

    Belyaev, Vladimir; Ivanova, Nadezda; Ivanov, Maxim; Bondarev, Valery; Lugovoy, Nikolay; Aseeva, Elena; Malyutina, Alisa

    2017-04-01

    It is widely accepted that changes of land use or climatic conditions can exert profound impacts on river basin sediment budgets and associated particle-bound pollutant redistribution patterns at different temporal and spatial scales. It can be especially difficult to distinguish relative importance of particular factors when the changes occur more or less within the same time frame. Such situation is typical for most parts of the agricultural belt of Russia, as period of economic downfall associated with collapse of the former Soviet Union and later gradual recovery practically coincides with period of the most significant climate changes observed in the late 20th - early 21st Centuries. Therefore it seems interesting and important to consider possible changes of fluvial systems responses within the period from 1980s to the present under different spatial scales. Here we plan to present results of the almost 10-year period of investigations of sediment and associated pollutant redistribution spatial and temporal patterns in several small catchments within the Seim River Basin (Kursk Region, European Russia). Studies dealt with small catchments and small river basins in scales from 1-2 km2 to 200 km2 located in different parts of the main basin. Works carried out included detailed geomorphic surveys, soil and sediment sections and cores description and sampling in different locations (undisturbed, erosion, transit, deposition), remote sensing data and morphometric analysis, soil erosion modeling. Integration of the results allowed constructing sediment budgets, in most cases, for two time intervals (approximately - pre-1986 and post-1986, as the Chernobyl-derived 137Cs has been an important time mark at all the case study sites). It has been found out that combination of several major tendencies including abandonment and recultivation of arable fields, notable decrease of winter-frozen topsoil layer thickness and increase of heavy summer rainstorms magnitude and

  14. "Climate change impact on water resources - a challenge for IWRM". BRAHMATWINN - Twinning European and South Asian River Basins to enhance capacity and implement adaptive management approaches

    Science.gov (United States)

    Bartosch, A.; Pechstädt, J.; Müller Schmied, H.; Flügel, W.-A.

    2009-04-01

    BRAHMATWINN addresses climate change impact of the hydrology of two macro-scale river basins having headwaters in alpine mountain massifs. The project will elaborate on the consequential vulnerability of present IWRM and river basin management that have been persistent in these basins during the past decades and will develop tested approaches and technologies for adaptive IWRM and resilience. The overall objective of BRAHMATWINN is to enhance and improve capacity to carry out a harmonized integrated water resources management (IWRM) approach as addressed by the European Water Initiative (EWI) in headwater river systems of alpine mountain massifs in respect to impacts from likely climate change, and to transfer professional IWRM expertise, approaches and tools based on case studies carried out in twinning European and Asian river basins, the Upper Danube River Basin (UDRB) and the Upper Brahmaputra River Basin (UBRB). Sustainable IWRM in river basins of such kind face common problems: (i) floods e.g. during spring melt or heavy storms and droughts during summer; (ii) competing water demands for agriculture, hydropower, rural, urban and industrial development, and the environment; (iii) pollution from point as well as diffuse sources; and (iv) socio-economic and legal issues related to water allocation. Besides those common topics both basins also differ in other issues requiring the adaptation of the IWRM tools; these are for example climate conditions, the density of monitoring network, political framework and trans-boundary conflicts. An IWRM has to consider all water-related issues like the securing of water supply for the population in sufficient quantity and quality, the protection of the ecological function of water bodies and it has to consider the probability of natural hazards like floods and droughts. Furthermore the resource water should be threatened in a way that the needs of future generations can be satisfied. Sustainable development is one of the

  15. Impact of climate change on flood characteristics in Brahmaputra basin using a macro-scale distributed hydrological model

    Indian Academy of Sciences (India)

    Shyamal Ghosh; Subashisa Dutta

    2012-06-01

    Being the highest specific discharge river system in the world, the Brahmaputra river experiences a number of long-duration flood waves during the monsoon season annually. In order to assess the flood characteristics at the basin and tributary scales, a physically based macro-scale distributed hydrological model (DHM) has been calibrated and validated for 9 wet years. The model performance has been evaluated in terms of prediction of the flood characteristics such as peak discharge, flood duration, arrival time of flood wave, timing of the peak flow and number of flood waves per season. Future changes in the flood wave characteristics of the basin have been evaluated using the validated model with bias-corrected future-projected meteorological scenario from a regional climate model (RCM). Likelihood analysis of the simulated flow time series reveals that significant increase in both peak discharge and flood duration is expected for both the pre-monsoonal and monsoonal seasons in the basin, but the number of flood waves per season would be reduced. Under the projected climate change scenario, it is expected that there will be more catastrophic floods in the basin.

  16. Using remote sensing time series to model the impact of changing flooding regimes on riparian vegetation in Australia's most important river basin

    Science.gov (United States)

    Broich, M.; Tulbure, M. G.; Verbesselt, J.; Xin, Q.

    2016-12-01

    Australia is a continent subject to high rainfall variability, which has major influences on runoff and vegetation dynamics. However, the resulting spatial-temporal pattern of flooding and its influence on riparian vegetation has not been quantified in a spatially explicit way. Here we focused on the floodplains of the entire Murray-Darling Basin (MDB), an area that covers over 1M km2, as a case study. The MDB is the country's primary agricultural area with scarce water resources subject to competing demands and impacted by climate change and more recently by the Millennium Drought (1999-2009). Riparian vegetation in the MDB floodplain suffered extensive decline providing a dramatic degradation of riparian vegetation. We quantified the spatial-temporal impact of rainfall, temperature and flooding patters on vegetation dynamics at the subcontinental to local scales and across inter to intra-annual time scales based on three decades of Landsat (25k images), Bureau of Meteorology data and one decade of MODIS data. Vegetation response varied in space and time and with vegetation types, densities and location relative to areas frequently flooded. Vegetation degradation trends were observed over riparian forests and woodlands in areas where flooding regimes have changed to less frequent and smaller inundation extents. Conversely, herbaceous vegetation phenology followed primarily a `boom' and `bust' cycle, related to inter-annual rainfall variability. Spatial patters of vegetation degradation changed along the N-S rainfall gradient but flooding regimes and vegetation degradation patterns also varied at finer scale, highlighting the importance of a spatially explicit, internally consistent analysis and setting the stage for investigating further cross-scale relationships. Results are of interest for land and water management decisions. The approach developed here can be applied to other areas globally such as the Nile river basin and Okavango River delta in Africa or the

  17. Temporal trends of persistent organic pollutants in dated sediment cores: Chemical fingerprinting of the anthropogenic impacts in the Seine River basin, Paris.

    Science.gov (United States)

    Lorgeoux, C; Moilleron, R; Gasperi, J; Ayrault, S; Bonté, P; Lefèvre, I; Tassin, B

    2016-01-15

    Persistent organic pollutants (POPs) were extensively produced and used throughout the last century. In the early 1980s, a rising concern on the environmental impact of these chemicals has led to the establishment of regulations and changes of use including bans. Long term monitoring of the environmental impacts of these emissions and regulations is a challenge because regular monitoring was not mandatory at the beginning of the first emissions. Moreover, the analytical methods have been strongly improved over the decades. To overcome the lack of monitoring and accurate data, sediment cores are powerful tools to construct contamination records. In this study, a high resolution record was constructed for four POPs families (13 polycyclic aromatic hydrocarbons (PAHs), 15 polychlorinated biphenyls (PCBs), 3 alkylphenols (APs) and 8 polybromodiphenyl ethers (PBDEs)) to establish their historical trends in a long-term urbanized and industrialized environment: the Seine River basin, France. These specific families were selected because they had different sources, uses and histories. The results showed concentrations up to 90 mg/kg for ∑PAHs, 2.3mg/kg for ∑PCB, 1.2mg/kg for ∑APs and 0.06 mg/kg for ∑PBDE. The vertical distribution profiles were different from one family to another and presented a good correlation with uses (e.g. transition from coal to natural gas for PAHs), and regulation implementation (e.g., AP ban after "OSPAR Convention" in 1992). The study of compounds distribution provided original information on sources, e.g. temporal variations in PAH uses. This study demonstrates the usefulness and accuracy of sedimentary archives in floodplain to assess the fate of POPs through time in continental hydrosystems. These first results give a comprehensive overview of the contamination in the Seine River basin downstream of Paris Megacity. They were in good agreement with previous studies dedicated to European areas and highlighted specificities of this basin

  18. 气候变化对大凌河流域径流影响研究%Impact of Climate Change on Runoff in Dalinghe River Basin

    Institute of Scientific and Technical Information of China (English)

    郭清; 吴俊秀

    2012-01-01

    利用区域气候模型PRECIS RCM模拟结果分析了研究流域未来温室气体在A2排放模式下规划水平年气候变化情况.将PRECIS模型模拟降水、蒸散发数据输入水文降雨径流NAM模型中,分析未来气候变化对研究流域径流影响.分析结果表明,未来气候变化条件下,受降水、蒸发变化影响,大凌河流域径流量会显著增加.%The results from the local climate model PRECIS were used to give an indication of the likely climate response in the study basin at planning horizons under two scenarios (A2 and B2) of future greenhouse gas emissions. These data of daily precipitation, potential evaporation derived from PRECIS model were in turn used as inputs to deterministic hydrological rainfall-runoff model (NAM), through which the impacts of future climate change on runoff could be assessed. The indications are that there will be significantly increased runoff in the Dalinghe River Basin due to the changes of precipitation and evaporation in future, which will be impacted by climate change.

  19. Changes in the Rain-Snow Transition Elevation: The Impact of Climate Warming on the Spatial Variability of Snow and the Hydrology of Mountains Basins (Invited)

    Science.gov (United States)

    Marks, D. G.; Reba, M. L.; Winstral, A. H.; Kumar, M.

    2010-12-01

    The hydrology of mountain regions is determined by precipitation phase, volume and distribution. The complexities of precipitation volume and distribution are the result of a complex interplay between regional orographic effects, and local-scale wind field interaction with vegetation and topographic structure. Air-mass characteristics interact with the elevation range of mountain systems to determine the precipitation phase and the elevation of the rain-snow transition. The makeup of forest and river systems in mountain basins is a reflection of the stability of the rain-snow transition elevation over a long period of time. However, in a rapidly changing and warming climate, the rain-snow transition is no longer stable, and is moving to higher elevations. This will have a dramatic impact on mountain hydrology, streamflow, and our ability to predict water supplies from mountain regions. Detailed data on precipitation, snow, and meteorological conditions along an elevation gradient within the Reynolds Creek Experimental Watershed (RCEW) in the Owyhee Mountains of Idaho, USA are used to examine changes to the rain-snow transition elevation over the last 50 years. We present specific examples of how these changes have impacted snow distribution at watershed scales within the RCEW, including a reduction in redistribution, drifting and earlier melt-out, resulting in increased winter streamflow and decreased summer streamflow. We also show how these changes are likely to affect patterns of snow deposition across the northern Great Basin.

  20. Credibility of Hydrologic Models in the Context of Climate Change Impact Studies - A Case Study in the Olifants Basin, South Africa

    Science.gov (United States)

    Wagener, Thorsten; van Werkhoven, Kathryn; Singh, Riddhi

    2010-05-01

    A major challenge for hydrologic research in the coming years will be the assessment of climate change impacts on regional water resources. While more and more impact studies are being performed, the assessment of hydrologic changes across a region, particularly in less developed countries, is often severely limited by the lack of streamflow gauges to calibrate watershed models and hence large uncertainties of model predictions. Further, one has to ask the general question of how we can increase the credibility of watershed models in the context of climate change studies, where, by definition, the model's credibility cannot simply be derived from its performance in reproducing historical observations. The study region is the Olifants basin in South Africa, a UNESCO HELP basin that is characterized by severe water insecurity and regular hydrologic extreme events. We will demonstrate how we can trade space-for-time by using spatial gradients as first order approximation of temporal changes in watershed behavior to derive ensemble predictions at both gauged and ungauged sites. In general, there is an urgent need to re-think how we identify, use and evaluate hydrological models under non-stationary conditions to increase the value of studies such as this one for water resource planning and decision making.

  1. Anthropogenic point-source and non-point-source nitrogen inputs into Huai River basin and their impacts on riverine ammonia-nitrogen flux

    Science.gov (United States)

    Zhang, W. S.; Swaney, D. P.; Li, X. Y.; Hong, B.; Howarth, R. W.; Ding, S. H.

    2015-07-01

    This study provides a new approach to estimate both anthropogenic non-point-source and point-source nitrogen (N) inputs to the landscape, and determines their impacts on riverine ammonia-nitrogen (AN) flux, providing a foundation for further exploration of anthropogenic effects on N pollution. Our study site is Huai River basin of China, a water-shed with one of the highest levels of N input in the world. Multi-year average (2003-2010) inputs of N to the watershed are 27 200 ± 1100 kg N km-2 yr-1. Non-point sources comprised about 98 % of total N input, and only 2 % of inputs are directly added to the aquatic ecosystem as point sources. Fertilizer application was the largest non-point source of new N to the Huai River basin (69 % of net anthropogenic N inputs), followed by atmospheric deposition (20 %), N fixation in croplands (7 %), and N content of imported food and feed (2 %). High N inputs showed impacts on riverine AN flux: fertilizer application, point-source N input, and atmospheric N deposition were proved as more direct sources to riverine AN flux. Modes of N delivery and losses associated with biological denitrification in rivers, water consumption, interception by dams may influence the extent of export of riverine AN flux from N sources. Our findings highlight the importance of anthropogenic N inputs from both point sources and non-point sources in heavily polluted watersheds, and provide some implications for AN prediction and management.

  2. Anthropogenic point and non-point nitrogen inputs into Huai River Basin and their impacts on riverine ammonia-nitrogen flux

    Science.gov (United States)

    Zhang, W. S.; Swaney, D. P.; Li, X. Y.; Hong, B.; Howarth, R. W.; Ding, S. H.

    2015-02-01

    This study provides a new approach to estimate both anthropogenic non-point and point nitrogen (N) inputs to the landscape, and determines their impacts on riverine ammonia-nitrogen (AN) flux, providing a foundation for further exploration of anthropogenic effects on N pollution. Our study site is Huai River Basin of China, a watershed with one of the highest levels of N input in the world. Multi-year average (2003-2010) inputs of N to the watershed are 27 200 ± 1100 kg N km-2 yr-1. Non-point sources comprised about 98% of total N input and only 2% of inputs are directly added to the aquatic ecosystem as point sources. Fertilizer application was the largest non-point source of new N to the Huai River Basin (69% of net anthropogenic N inputs), followed by atmospheric deposition (20%), N fixation in croplands (7%), and N content of imported food and feed (2%). High N inputs showed impacts on riverine AN flux: fertilizer application, point N input and atmospheric N deposition were proved as more direct sources to riverine AN flux. Modes of N delivery and losses associated with biological denitrification in rivers, water consumption, interception by dams influenced the extent of export of riverine AN flux from N sources. Our findings highlight the importance of anthropogenic N inputs from point and non-point sources in heavily polluted watersheds, and provide some implications for AN prediction and management.

  3. Ar-40/Ar-39 age spectra of Apollo 15 impact melt rocks by laser step-heating and their bearing on the history of lunar basin formation

    Science.gov (United States)

    Dalrymple, G. B.; Ryder, Graham

    1993-01-01

    Results are reported on 26 high-resolution (16-51 steps) Ar-40/Ar-39 age spectra obtained on 12 Apollo-15 melt rocks of different composition using a continuous laser system on submg fragments of recrystallized melt and single-crystal plagioclase clasts from impact melt rocks collected at the Apennine Front where the Imbrium and Serenitatis basins intersect. A table is presented with the summary of the Ar-40/Ar-39 spectrum data, which represent 891 individual temperature step analyses. Also presented are 20 of the 26 age spectra along with their respective K/Ca plots. Melt rock fragments and plagioclase clasts from seven of the 12 samples analyzed yielded reproducible, intermediate-T Ar-40/Ar-39 age spectrum plateaus, which were interpreted as crystallization ages that represent the times of impact of bolides onto the lunar surface.

  4. Impacts of Climate Change on Vector Borne Diseases in the Mediterranean Basin — Implications for Preparedness and Adaptation Policy

    OpenAIRE

    Maya Negev; Shlomit Paz; Alexandra Clermont; Noemie Groag Pri-Or; Uri Shalom; Tamar Yeger; Green, Manfred S

    2015-01-01

    The Mediterranean region is vulnerable to climatic changes. A warming trend exists in the basin with changes in rainfall patterns. It is expected that vector-borne diseases (VBD) in the region will be influenced by climate change since weather conditions influence their emergence. For some diseases (i.e., West Nile virus) the linkage between emergence andclimate change was recently proved; for others (such as dengue) the risk for local transmission is real. Consequently, adaptation and prepar...

  5. BASIN-RANGE SYSTEM EVOLUTION OF QINLING-DABIE OROGENIC BELT AND ITS IMPACT ON REGIONAL ENVIRONMENT

    Institute of Scientific and Technical Information of China (English)

    HU Baoqing; ZENG Qiaosong; LIU Shunsheng; WANG Shijie

    2004-01-01

    As the structural body related to temporal-spatial evolution and tectonic dynamic system, the orogenic belt and basin are not only dependent on each other in space but also closely related with each other in terms of infrastructure, matter transference and dynamic mechanisms. By using apatite fission-track method, the authors firstly analyze the uplift and denudation ratios of the Qinling-Dabie orogenic belt, and by using tectonically deformed combination analysis and tectonic-thermal simulation the main geological occurrences are also illustrated. It is found that there must have had multi-phase differential uplift and denudation phenomena in the Qinling-Dabie orogenic belt during the Mesozoic-Cenozoic. Then, the regional evolution pattern of qualitative and quantitative denudation process is obtained during the post-orogenic period. On the basis of summarizing evolution process of the basin-range system in the Qinling-Dabie orogenic belt during the Mesozoic-Cenozoic and its effects on regional environment, the influence of evolution process on geomorphologic landscapes change, water system vicissitude, eco-environment succession and drainage basin system evolution is discussed.

  6. Exploring the Potential Impact of Serious Games on Social Learning and Stakeholder Collaborations for Transboundary Watershed Management of the St. Lawrence River Basin

    Directory of Open Access Journals (Sweden)

    Wietske Medema

    2016-04-01

    Full Text Available The meaningful participation of stakeholders in decision-making is now widely recognized as a crucial element of effective water resource management, particularly with regards to adapting to climate and environmental change. Social learning is increasingly being cited as an important component of engagement if meaningful participation is to be achieved. The exact definition of social learning is still a matter under debate, but is taken to be a process in which individuals experience a change in understanding that is brought about by social interaction. Social learning has been identified as particularly important in transboundary contexts, where it is necessary to reframe problems from a local to a basin-wide perspective. In this study, social learning is explored in the context of transboundary water resource management in the St. Lawrence River Basin. The overarching goal of this paper is to explore the potential role of serious games to improve social learning in the St. Lawrence River. To achieve this end, a two-pronged approach is followed: (1 Assessing whether social learning is currently occurring and identifying what the barriers to social learning are through interviews with the region’s water resource managers; (2 Undertaking a literature review to understand the mechanisms through which serious games enhance social learning to understand which barriers serious games can break down. Interview questions were designed to explore the relevance of social learning in the St. Lawrence River basin context, and to identify the practices currently employed that impact on social learning. While examples of social learning that is occurring have been identified, preliminary results suggest that these examples are exceptions rather than the rule, and that on the whole, social learning is not occurring to its full potential. The literature review of serious games offers an assessment of such collaborative mechanisms in terms of design principles

  7. Young Valley Networks on Mars: Persistent Flow of Water in Lyot Crater, a Distinctive Amazonian Impact Basin Microenvironment

    Science.gov (United States)

    Dickson, J.; Fassett, C.; Head, J.

    2008-09-01

    Introduction While Amazonian fluvial landforms are not abundant on Mars, remote sensing data have revealed details regarding the role of ice in non-polar regions in the Amazonian. Evidence includes 1) deposits interpreted to be remnants of cold-based glaciers at low- and mid-latitudes [1-6]; 2) mantling deposits interpreted to be a desiccating layer of ground ice [7- 8]; 3) detection of hydrogen (inferred to be bound as water ice) in soil in the mid- and high-latitudes in each hemisphere [9-10]; and 4) viscous flow features interpreted to be the product of glacial-like flow along steep valley/crater walls [11-12]. The climate of Mars straddles the triple point, which motivated us to investigate the most-likely locations/microclimates for melting of these surface/near-surface ice features [13-14]: large-scale impact craters at low elevations and mid-latitudes, which provide 1) relatively high surface pressure; 2) increased solor insolation; and 3) potential residual thermal anomalies from the impact event. Lyot Crater, a ~215 km peak-ring impact basin in the northern lowlands of Mars (50°N, 30°E), provides an environment that meets these constraints. We analyzed recently obtained CTX data to document evidence of remnant glacial deposits and surface features that appear indicative of melting and drainage. Description The floor of Lyot exhibits several networks of sinuous valleys that have been incised exclusively into a pervasive stippled mantling unit (Fig. 1). Twenty separate networks are observed in CTX and THEMIS data, 15 of which occur in the eastern half of Lyot. The valleys range in length from short, 2 km long isolated valleys to 50 km long networks of multiple valleys that have widths that average ~250 m. Valley floors are smooth at CTX resolution, in contrast to the adjacent stippled mantling unit (Fig. 1). Profiles extracted from the Mars Orbiter Laser Altimeter (MOLA) data set show that, without exception, the valleys follow the local topographic

  8. The Cretaceous-Paleogene boundary unit in the Gulf of Mexico: Large-scale oceanic basin response to the Chicxulub impact

    Science.gov (United States)

    Sanford, J. C.; Gulick, S. P.; Snedden, J.

    2013-12-01

    The prevailing theory for the Cretaceous-Paleogene (K-Pg) extinction event cites the Chicxulub asteroid impact on the Yucatán Peninsula as the catalyst for the global climatologic and ecologic crisis. This theory has been corroborated by a multitude of K-Pg boundary deposits observed globally in both boreholes and outcrops. The change in character of these deposits with proximity to the crater, from a millimeter-scale clay layer to a hectometer-scale carbonate sequence, supports a causal link between the boundary unit and the asteroid impact. Due to its passive marine setting and proximity to the Chicxulub crater, the Gulf of Mexico is the premier locale in which to study the near-field geologic effect of a massive bolide impact. Until recently, investigation of the K-Pg boundary deposit within the Gulf has been largely confined to outcrops and boreholes on the periphery of the basin due to the difficulty of observation of the boundary unit in the deep water. However, hydrocarbon exploration in the past decade has yielded significant borehole and seismic data that can be used to better understand the deep-water response to the impact and to gain a comprehensive regional understanding impact-related processes in the Gulf. Based on roughly 100 offshore and 300 onshore Cretaceous well penetrations, the K-Pg boundary is interpreted to range from a strictly erosional surface in shallow-water and coastal regimes to a mass transport deposit up to ~400 meters thick. Depth-converted seismic data throughout the Gulf corroborate such thicknesses and reveal that the deposit is virtually ubiquitous throughout the deep water. For the first time, the K-Pg boundary deposit has been tied from the central Gulf to the Chicxulub crater, further establishing a causative link between the two. Biostratigraphic data in wells confirm the age of the deposit and document the presence of the 'K-Pg boundary cocktail.' Seismic data reveals areas of extensive debris flows and slump deposits on

  9. Comparative analysis of two hydrological models with different glacier parameterisations for climate impact assessment and water resources management in the Syrdarya Basin, Central Asia

    Science.gov (United States)

    Gafurov, Abror; Duethmann, Doris; Agaltseva, Natalya; Merkushkin, Alexander; Pak, Alexander; Kriegel, David; Huss, Matthias; Güntner, Andreas; Merz, Bruno; Unger-Shayesteh, Katy; Mannig, Birgit; Paeth, Heiko; Vorogushyn, Sergiy

    2014-05-01

    Central Asian river basins in general and zones of run-off formation in particular are currently experiencing the impact of increasing temperatures and changes in precipitation. The headwaters thus exhibit negative glacier mass balances, decreasing glacierisation, changes in snow cover characteristics and changing runoff response. These changes are likely to intensify in future under the changing climate. Both hydropower industry and irrigated agriculture in the downstream areas strongly depend on the water amount, its seasonal and long-term distribution. This fact calls for an effort to reliably assess water availability in the runoff formation zone of Central Asia in order to improve water management policy in the region. One of the approaches to assessment of water resources is the evaluation of climate scenarios with the climate-and-hydrology model chain. Application of several models allows reducing the modeling uncertainty and proceeding with more robust water balance components assessment. We present the comparison of the two hydrological models AISHF (Automated Information System for Hydrological Forecasting) developed at the Centre for Hydrometeorology of Uzbekistan and WASA run at GFZ Potsdam, implemented for the Naryn and Karadarya basins (Syrdarya). These models use different parameterization and calibration schemes. Whereas in the AISHF model glacier dynamics is considered in scenarios of glacier area loss, the WASA model simulates continuous glacier mass balance, glacier area and volume evolution based on meteorological drivers. Consideration of initial glacier volume and its temporal dynamics can be essential for climate impact assessment in transient model simulations. The impact of climate change scenarios, developed with the regional climate model REMO at the University of Würzburg, are compared with respect to total discharge dynamics and runoff contributions from glacier, snowmelt and rainfall. Implications of water availability assessment

  10. The impact of poplar tree plantations for biomass production on the aquifer water budget and base flow in a Mediterranean basin

    Energy Technology Data Exchange (ETDEWEB)

    Folch, Albert, E-mail: folch.hydro@gmail.com [Hydrogeology Group (UPC-CSIC), Department of Geotechnical Engineering and Geo-sciences, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona (Spain); Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra (Spain); Ferrer, Núria [Hydrogeology Group (UPC-CSIC), Department of Geotechnical Engineering and Geo-sciences, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona (Spain)

    2015-08-15

    Poplar plantations are used for biomass production in many countries. These plantations are often located in areas where the tree roots can reach the water table of shallow aquifers to reduce irrigation costs and increase evapotranspiration, mainly during the summer. This study aims to assess the effects of these plantations on an aquifer water budget and on the stream flow of a Mediterranean basin (Santa Coloma River, 321.3 km{sup 2} NE Spain). A numerical flow model was constructed to simulate shallow aquifers and to simulate the stream–aquifer interaction for a period of 9 years. Once the model was calibrated, different land use scenarios, such as deciduous forests, dry farming and irrigated farming, were simulated for comparison. The mass balance shows that poplar extracts an average of 2.40 hm{sup 3} from the aquifer, i.e., approximately 18% of the average recharge of the modelled area. This effect reduces the groundwater flow to the main stream and increases the infiltration from the stream to the aquifer. As a result, there is an average reduction in the main stream flow by 46% during the summer, when the lowest flow occurs and when the river is most sensitive. The results indicate that these impacts should be considered in basin management plans and in evaluating the benefits of this type of biomass production. - Highlights: • Poplar plantations can evapotranspirate aquifer groundwater in semiarid areas • A groundwater flow model is presented to quantify poplars’ impact on the water budget • 20% of the aquifer recharge is consumed by poplars • The main stream flow is reduced up to 46% during summer due to plantations uptake • Biomass production impacts must be considered for evaluating water resources planning.

  11. Basin-Forming Impact Events on Mercury: Effects on Melt Production and Depth of the Source Region

    Science.gov (United States)

    Padovan, S.; Tosi, N.; Plesa, A.-C.

    2016-08-01

    In this work we investigate to which degree large impact events on Mercury can modify the underlying mantle dynamics and how the presence of post-impact volcanism or lack thereof can be related to the planet's interior properties.

  12. Using chemical and microbiological indicators to track the impacts from the land application of treated municipal wastewater and other sources on groundwater quality in a karstic springs basin

    Science.gov (United States)

    Katz, B.G.; Griffin, Dale W.

    2008-01-01

    Multiple chemical constituents (nutrients; N, O, H, C stable isotopes; 64 organic wastewater compounds, 16 pharmaceutical compounds) and microbiological indicators were used to assess the impact on groundwater quality from the land application of approximately 9.5 million liters per day of treated municipal sewage effluent to a sprayfield in the 960-km2 Ichetucknee Springs basin, northern Florida. Enriched stable isotope signatures (?? 18O and ??2H) were found in water from the effluent reservoir and a sprayfield monitoring well (MW-7) due to evaporation; however, groundwater samples downgradient from the sprayfield have ??18O and ??2H concentrations that represented recharge of meteoric water. Boron and chloride concentrations also were elevated in water from the sprayfield effluent reservoir and MW-7, but concentrations in groundwater decreased substantially with distance downgradient to background levels in the springs (about 12 km) and indicated at least a tenfold dilution factor. Nitrate-nitrogen isotope (??15N-NO3) values above 10 ??? in most water samples were indicative of organic nitrogen sources except Blue Hole Spring (??15N-NO3 = 4.6-4.9 ???), which indicated an inorganic source of nitrogen (fertilizers). The detection of low concentrations the insect repellent N,N-diethyl-metatoluamide (DEET), and other organic compounds associated with domestic wastewater in Devil's Eye Spring indicated that leakage from a nearby septic tank drainfield likely has occurred. Elevated levels of fecal coliforms and enterococci were found in Blue Hole Spring during higher flow conditions, which likely resulted from hydraulic connections to upgradient sinkholes and are consistent with previoius dye-trace studies. Enteroviruses were not detected in the sprayfield effluent reservoir, but were found in low concentrations in water samples from a downgradient well and Blue Hole Spring during high-flow conditions indicating a human wastewater source. The Upper Floridan aquifer in

  13. A Re-Examination of the Bedout High, Offshore Canning Basin, Western Australia - Possible Impact Site for the Permian-Triassic Mass Extinction Event?

    Science.gov (United States)

    Becker, L.; Nicholson, C.; Poreda, R. J.

    2002-12-01

    The Bedout High, located offshore Canning basin in Western Australia, is an unusual structure and its origin remains problematic. K-Ar dating of volcanic samples encountered at total depth in the Lagrange-1 exploration well indicated an age of about 253+/-5 Ma consistent with the Permian-Triassic boundary event. Gorter (PESA News, pp. 33-34, 1996) speculates that the Bedout High is the uplifted core (30 km) of a circular feature, some 220 km across, formed by the impact of a large bolide (cometary or asteroidal) with the Earth near the end-Permian. Accepting a possible impact origin for the Bedout structure, with the indicated dimensions, would have had profound effects on global climate as well as significant changes in lithotratigraphic, biostratigraphic and chemostratigraphic indicators as seen in several Permian-Triassic boundary locations worldwide. In this work, we re-examine some of the structural data previously presented by Gorter (1996) using some additional seismic lines. We have also evaluated several impact tracers including iridium, shocked quartz, productivity collapse, helium-3, chromium-53 and fullerenes with trapped noble gases from some Permian-Triassic boundary sites in the Tethys and Circum-Pacific regions. Our findings suggest that the Bedout structure is a good candidate for an oceanic impact at the end Permian, triggering the most severe mass extinction in the history of life on Earth.

  14. The impacts of climate change and land cover/use transition on the hydrology in the upper Yellow River Basin, China

    Science.gov (United States)

    Cuo, Lan; Zhang, Yongxin; Gao, Yanhong; Hao, Zhenchun; Cairang, Luosang

    2013-10-01

    Observed streamflow over the past decades in the upper Yellow River Basin (UYRB) was examined for changes in hydrological regime. The modified Variable Infiltration Capacity (VIC) model was employed to better understand climate change impact and long-term and recent land cover/use change impact as it relates to the "Grain for Green Project" and "Three Rivers Source Region Reserve" on water resources by examining mechanisms behind observed streamflow changes. UYRB hydrological regimes have undergone changes over the past decades as reflected by a decrease in wet and warm season streamflow, and annual streamflow. Progressively more streamflow has been generated in the early part of the year compared to the latter part, consequently leading to the earlier occurrence of the day representing the midpoint of yearly mass flow. VIC simulations suggest that these changes in observed streamflow were due to the combined effects of changes in precipitation, evapotranspiration, rainfall runoff, and baseflow and were caused primarily by climate change above Tang Nai Hai (TNH) hydrometric station. Below TNH where human activity is relative intense, land cover/use change and reservoir release impacts became important. Changes in snowmelt runoff were negligible over the past decades. Owing to this, snowmelt runoff appeared to play only a modest role in the changing hydrology of the region. The conservation programs were shown to start to exhibit some positive impacts on water resources in the UYRB.

  15. Modelling the impact of large dams on flows and hydropower production of the Sekong, Sesan and Srepok Rivers in the Mekong Basin

    Science.gov (United States)

    Piman, T.; Cochrane, T. A.; Arias, M. E.

    2013-12-01

    Water flow patterns in the Mekong River and its tributaries are changing due to water resources development, particularly as a result of on-going rapid hydropower development of tributaries for economic growth. Local communities and international observers are concerned that alterations of natural flow patterns will have great impacts on biodiversity, ecosystem services, food securing and livelihood in the basin. There is also concern that un-coordinated dam development will have an adverse impact on energy production potential of individual hydropower plants. Of immediate concern is the proposed hydropower development in the transboundary Srepok, Sesan and Srekong (3S) Basin, which contributes up to 20% of the Mekong's annual flows, has a large potential for energy production, and provides critical ecosystem services to local people and the downstream Tonle Sap Lake and the Mekong delta. To assess the magnitude of potential changes in flows and hydropower production, daily flows were simulated over 20 years (1986-2005) using the SWAT and HEC ResSim models for a range of dam development and operations scenarios. Simulations of all current and proposed hydropower development in the 3S basin (41 dams) using an operation scheme to maximize electricity production will increase average dry seasonal flows by 88.1% while average wet seasonal flows decrease by 24.7% when compared to the baseline (no dams) scenario, About 55% of dry season flows changes are caused by the seven largest proposed dams (Lower Srepok 3, Lower Srepok4, Lower Sesan 3, Lower Sesan and Srepok 2, Xekong 5, Xekong 4, and Xe Xou). The total active storage of the existing and ongoing hydropower projects is only 6,616 million m3 while the cumulative active storage of the seven large proposed dams is 17,679 million m3. The Lower Srepok 3 project causes the highest impact on seasonal flow changes. Average energy production of the existing and ongoing hydropower projects is 73.2 GWh/day. Additional benefits

  16. Modeling the impacts of climate change and agricultural management practices on surface erosion in a dryland agricultural basin

    Science.gov (United States)

    Ottenbreit, E.; Adam, J. C.; Barber, M. E.

    2010-12-01

    The objective of this study is to investigate the effects of climate change and agricultural management practices on suspended sediment concentrations in the Potlach River basin in northwestern Idaho. Suspended sediment is a pollutant in many water systems and contributes to the impairment of streams. Conventional tillage practices and rain-on-snow events in the Palouse region of northern Idaho and eastern Washington can produce some of the highest sediment losses per acre in the United States. Climate change may lead to further problems as more frequent and intense winter storm events are predicted to occur. Many hydrological models have been developed which examine suspended sediment in river systems. The Potlatch River basin near Julietta, ID was examined using the Distributed Hydrology Soil Vegetation Model (DHSVM), which has a sediment module that includes surface erosion and channel sediment transport. DHSVM was calibrated and evaluated over the historical period of streamflow observations and was used to predict soil erosion rates and suspended sediment concentrations using a range of downscaled Global Climate Models (GCMs) emissions scenarios for the year 2045. Furthermore, the sensitivity of suspended sediment concentrations to conventional versus convservative tillage practices was explored. The results show that as the projected climate-driven intensity of storms increase, more sediment is predicted in the Potlatch River. Suspended sediment and streamflow are predicted to increase during the late fall through the early spring. This increase occurs during times of heightened runoff when suspended sediment concentration in the river is highest. Three tillage scenarios were incorporated into DHSVM for winter wheat: conventional till, reduced till, and no till. Erosion and suspended sediment were higher during storm events under conventional agricultural tillage scenarios. In the long-term, this research can lead to examination of the effects of climate

  17. The impact of poplar tree plantations for biomass production on the aquifer water budget and base flow in a Mediterranean basin.

    Science.gov (United States)

    Folch, Albert; Ferrer, Núria

    2015-08-15

    Poplar plantations are used for biomass production in many countries. These plantations are often located in areas where the tree roots can reach the water table of shallow aquifers to reduce irrigation costs and increase evapotranspiration, mainly during the summer. This study aims to assess the effects of these plantations on an aquifer water budget and on the stream flow of a Mediterranean basin (Santa Coloma River, 321.3 km(2) NE Spain). A numerical flow model was constructed to simulate shallow aquifers and to simulate the stream-aquifer interaction for a period of 9 years. Once the model was calibrated, different land use scenarios, such as deciduous forests, dry farming and irrigated farming, were simulated for comparison. The mass balance shows that poplar extracts an average of 2.40 hm(3) from the aquifer, i.e., approximately 18% of the average recharge of the modelled area. This effect reduces the groundwater flow to the main stream and increases the infiltration from the stream to the aquifer. As a result, there is an average reduction in the main stream flow by 46% during the summer, when the lowest flow occurs and when the river is most sensitive. The results indicate that these impacts should be considered in basin management plans and in evaluating the benefits of this type of biomass production. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Assessment of climate change impact on river flow regimes in The Red River Delta, Vietnam – A case study of the Nhue-Day River Basin

    Directory of Open Access Journals (Sweden)

    Phan Cao Duong

    2016-09-01

    Full Text Available Global warming has caused dramatic changes in regional climate variability, particularly regarding fluctuations in temperature and rainfall. Thus, it is predicted that river flow regimes will be altered accordingly. The purpose of this paper is to present the results of modeling such changes by simulating discharge using the HEC-HMS model. The precipitation was projected using super-high resolution multiple climate models (20 km resolution with newly updated emission scenarios as the input for the HEC-HMS model for flow analysis at the Red River Basin in the northern area of Vietnam. The findings showed that climate change impact on the river flow regimes tend towards a decrease in the dry season and a longer duration of flood flow. A slight runoff reduction is simulated for November while a considerable runoff increase is modeled for July and August amounting to 30% and 25%, respectively. The discharge scenarios serve as a basis for water managers to develop suitable adaptation methods and responses on the river basin scale.

  19. GIS and remote sensing techniques for the assessment of land use change impact on flood hydrology: the case study of Yialias basin in Cyprus

    Science.gov (United States)

    Alexakis, D. D.; Grillakis, M. G.; Koutroulis, A. G.; Agapiou, A.; Themistocleous, K.; Tsanis, I. K.; Michaelides, S.; Pashiardis, S.; Demetriou, C.; Aristeidou, K.; Retalis, A.; Tymvios, F.; Hadjimitsis, D. G.

    2014-02-01

    Floods are one of the most common natural disasters worldwide, leading to economic losses and loss of human lives. This paper highlights the hydrological effects of multi-temporal land use changes in flood hazard within the Yialias catchment area, located in central Cyprus. A calibrated hydrological model was firstly developed to describe the hydrological processes and internal basin dynamics of the three major subbasins, in order to study the diachronic effects of land use changes. For the implementation of the hydrological model, land use, soil and hydrometeorological data were incorporated. The climatic and stream flow data were derived from rain and flow gauge stations located in the wider area of the watershed basin. In addition, the land use and soil data were extracted after the application of object-oriented nearest neighbor algorithms of ASTER satellite images. Subsequently, the cellular automata (CA)-Markov chain analysis was implemented to predict the 2020 land use/land cover (LULC) map and incorporate it to the hydrological impact assessment. The results denoted the increase of runoff in the catchment area due to the recorded extensive urban sprawl phenomenon of the last decade.

  20. Projection of climate change impacts on precipitation using soft-computing techniques: A case study in Zayandeh-rud Basin, Iran

    Science.gov (United States)

    Kouhestani, Shapour; Eslamian, Sayed Saeid; Abedi-Koupai, Jahangir; Besalatpour, Ali Asghar

    2016-09-01

    Due to the complexity of climate-related processes, accurate projection of the future behavior of hydro-climate variables is one of the main challenges in climate change impact assessment studies. In regression-based statistical downscaling processes, there are different sources of uncertainty arising from high-dimensionality of atmospheric predictors, nonlinearity of empirical and quantitative models, and the biases exist in climate model simulations. To reduce the influence of these sources of uncertainty, the current study presents a comprehensive methodology to improve projection of precipitation in the Zayandeh-Rud basin in Iran as an illustrative study. To reduce dimensionality of atmospheric predictors and capture nonlinearity between the target variable and predictors in each station, a supervised-PCA method is combined with two soft-computing machine-learning methods, Support Vector Regression (SVR) and Relevance Vector Machine (RVM). Three statistical transformation methods are also employed to correct biases in atmospheric large-scale predictors. The developed models are then employed on outputs of the Coupled Model Intercomparison Project Phase 5 (CMIP5) multimodal dataset to project future behavior of precipitation under three climate changes scenarios. The results indicate reduction of precipitation in the majority of the sites in this basin threatening the availability of surface water resources in future decades.

  1. Impacts of production of hydrocarbons in Campos Basin: missing or not detected; Impactos da producao de hidrocarbonetos na Bacia de Campos: ausentes ou nao detectados

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Carolina E. [Instituto Brasileiro de Meio Ambiente e Recursos Naturais Renovaveis (CGPEG/DILIC/IBAMA), Rio de Janeiro, RJ (Brazil). Coordenacao Geral de Petroleo e Gas. Diretoria de Licenciamento; Gama, Bernardo A. Perez da [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2012-07-01

    According to the Brazilian legislation, the Environmental Impacts Monitoring Plan is one of the requirements of the environmental licensing to offshore oil and gas production activities. The Monitoring Plan's structure is based upon sampling and evaluation of numerous parameter settings in water and sediment compartments, while the conclusion as to the existence or absence of impact is obtained after statistical analysis of the results. The aim of this work was to evaluate the methodological adequacy of monitoring and to calculate the statistical power of tests applied with the purpose to determine the reliability of their findings. Experiences in other countries like Australia have shown that this is an important instrument in preparing an effective environmental study regarding the detection of impacts. In Brazil, this is the first initiative to critically evaluate the results of reports of environmental monitoring originated from the licensing of hydrocarbons production activities. Campaign reports forwarded to the environmental agency in charge, i.e., the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA), and the selected ventures are located in the Campos Basin and have different operating companies. The results were both relevant and concerning. All monitoring reports confirmed the absence of alterations or impacts on the biotic media for sediment compartments, but the greater statistical power did not exceed 25% for a great magnitude impact. Thus it was concluded that if the oil production activity has caused alterations or impacts to bentonic organisms, the carried out monitoring was inefficient to detect them even if they were of great magnitude. This analysis is expected to be an instrument for future changes in environmental licensing procedures e for the improvement of the environmental public management in Brazil. (author)

  2. Impact of climate change on evaluation of future water demand in the Euphrates and Aleppo basin, Syria

    Science.gov (United States)

    Alazzy, A. A.; Lü, H.; Zhu, Y.

    2014-09-01

    Syria is one of the Middle Eastern countries that suffer from scarcity in water resources availability, which affects the growth and development of economic activities. In this research, the Water Evaluation and Planning (WEAP) model is applied to evaluate future water demand in the Euphrates and Aleppo basin (EAB), Syria, by taking into account the climate change that may affect water demand in the domestic, industrial, and agricultural sectors until 2050. The climate change projections of temperature and precipitation were assessed using a new version of the MAGICC/SCENGEN tool with two greenhouse gas emissions scenarios (A2 and B2) of the Intergovernmental Panel on Climate Change (IPCC). Based on the results of IPCC (A2, B2) scenarios projections, the EAB basin is likely to face a decrease in precipitation amount by 21 % according to A2 and by 12 % according to B2, while temperature would increase by about 2.5 °C according to A2 and by 2 °C according to B2. Within the three scenarios adopted in this research: (1) available technology development; (2) increasing treated wastewater in agriculture and industry sectors; (3) and two combined scenarios, the results of the simulation demonstrated that the proposed scenarios are effective for reducing stressors on EAB's water resources, but are not sustainable to bridge the gap between demand-supply by the year 2050, which leads to the deterioration of the available water resources.

  3. Impacts of Climate Change on Vector Borne Diseases in the Mediterranean Basin - Implications for Preparedness and Adaptation Policy.

    Science.gov (United States)

    Negev, Maya; Paz, Shlomit; Clermont, Alexandra; Pri-Or, Noemie Groag; Shalom, Uri; Yeger, Tamar; Green, Manfred S

    2015-06-15

    The Mediterranean region is vulnerable to climatic changes. A warming trend exists in the basin with changes in rainfall patterns. It is expected that vector-borne diseases (VBD) in the region will be influenced by climate change since weather conditions influence their emergence. For some diseases (i.e., West Nile virus) the linkage between emergence andclimate change was recently proved; for others (such as dengue) the risk for local transmission is real. Consequently, adaptation and preparation for changing patterns of VBD distribution is crucial in the Mediterranean basin. We analyzed six representative Mediterranean countries and found that they have started to prepare for this threat, but the preparation levels among them differ, and policy mechanisms are limited and basic. Furthermore, cross-border cooperation is not stable and depends on international frameworks. The Mediterranean countries should improve their adaptation plans, and develop more cross-sectoral, multidisciplinary and participatory approaches. In addition, based on experience from existing local networks in advancing national legislation and trans-border cooperation, we outline recommendations for a regional cooperation framework. We suggest that a stable and neutral framework is required, and that it should address the characteristics and needs of African, Asian and European countries around the Mediterranean in order to ensure participation. Such a regional framework is essential to reduce the risk of VBD transmission, since the vectors of infectious diseases know no political borders.

  4. Impacts of Climate Change on Vector Borne Diseases in the Mediterranean Basin — Implications for Preparedness and Adaptation Policy

    Directory of Open Access Journals (Sweden)

    Maya Negev

    2015-06-01

    Full Text Available The Mediterranean region is vulnerable to climatic changes. A warming trend exists in the basin with changes in rainfall patterns. It is expected that vector-borne diseases (VBD in the region will be influenced by climate change since weather conditions influence their emergence. For some diseases (i.e., West Nile virus the linkage between emergence andclimate change was recently proved; for others (such as dengue the risk for local transmission is real. Consequently, adaptation and preparation for changing patterns of VBD distribution is crucial in the Mediterranean basin. We analyzed six representative Mediterranean countries and found that they have started to prepare for this threat, but the preparation levels among them differ, and policy mechanisms are limited and basic. Furthermore, cross-border cooperation is not stable and depends on international frameworks. The Mediterranean countries should improve their adaptation plans, and develop more cross-sectoral, multidisciplinary and participatory approaches. In addition, based on experience from existing local networks in advancing national legislation and trans-border cooperation, we outline recommendations for a regional cooperation framework. We suggest that a stable and neutral framework is required, and that it should address the characteristics and needs of African, Asian and European countries around the Mediterranean in order to ensure participation. Such a regional framework is essential to reduce the risk of VBD transmission, since the vectors of infectious diseases know no political borders.

  5. Thermal impacts of magmatic intrusions on dolomitization processes in the Tiberias Basin, Jordan-Dead Sea Transform

    Science.gov (United States)

    Koltzer, Nora; Möller, Peter; Inbar, Nimrod; Siebert, Christian; Rosenthal, Eliyahu; Al-Raggad, Marwan; Magri, Fabien

    2017-04-01

    The Tiberias Basin (TB) is located within the Jordan-Dead Sea Transform and is bordered to the west by the Lower Galilee (Israel), where Pliocene basalts cover an area of 35 km2. Hydrochemical analyses highlight that two types of brines exist around Lake Tiberias (LT) (Mandel 1965; Möller et al. 2009): (1) Along the eastern side of LT, brine is characterized by Mg/Ca>1, which resulted from evaporation of seawater during the Late Miocene, whereas (2) along the western side of the lake, brine is characterized by Mg/CaMandel S. (1965). Hydrogeological Investigations of the areas surrounding Lake Tiberias. Water Planning for Israel. Volumes 1-2 210 p. Möller P., Siebert C., Geyer S., Inbar N., Rosenthal E., Flexer A., Zilberbrand M. (2012). Relationship of brines in the Kinnarot Basin, Jordan-Dead Sea Rift Valley. Geofluids, 12(2), 166-181. Möller P., Rosenthal E., Geyer S. (2009). Characterization of aquifer environments by major and minor elements and stable isotopes of sulfate In: Hoetzel H., Möller P., Rosenthal E. (Eds) Water of the Jordan Balley. Pp. 83-122.

  6. Predicting impacts of increased CO₂ and climate change on the water cycle and water quality in the semiarid James River Basin of the Midwestern USA.

    Science.gov (United States)

    Wu, Yiping; Liu, Shuguang; Gallant, Alisa L

    2012-07-15

    Emissions of greenhouse gases and aerosols from human activities continue to alter the climate and likely will have significant impacts on the terrestrial hydrological cycle and water quality, especially in arid and semiarid regions. We applied an improved Soil and Water Assessment Tool (SWAT) to evaluate impacts of increased atmospheric CO(2) concentration and potential climate change on the water cycle and nitrogen loads in the semiarid James River Basin (JRB) in the Midwestern United States. We assessed responses of water yield, soil water content, groundwater recharge, and nitrate nitrogen (NO(3)-N) load under hypothetical climate-sensitivity scenarios in terms of CO(2), precipitation, and air temperature. We extended our predictions of the dynamics of these hydrological variables into the mid-21st century with downscaled climate projections integrated across output from six General Circulation Models. Our simulation results compared against the baseline period 1980 to 2009 suggest the JRB hydrological system is highly responsive to rising levels of CO(2) concentration and potential climate change. Under our scenarios, substantial decrease in precipitation and increase in air temperature by the mid-21st century could result in significant reduction in water yield, soil water content, and groundwater recharge. Our model also estimated decreased NO(3)-N load to streams, which could be beneficial, but a concomitant increase in NO(3)-N concentration due to a decrease in streamflow likely would degrade stream water and threaten aquatic ecosystems. These results highlight possible risks of drought, water supply shortage, and water quality degradation in this basin. Published by Elsevier B.V.

  7. Predicting Impacts of Increased CO2 and Climate Change on the Water Cycle and Water Quality in the Semiarid James River Basin of the Midwestern USA

    Science.gov (United States)

    Wu, Yiping; Liu, Shu-Guang; Gallant, Alisa L.

    2012-01-01

    Emissions of greenhouse gases and aerosols from human activities continue to alter the climate and likely will have significant impacts on the terrestrial hydrological cycle and water quality, especially in arid and semiarid regions. We applied an improved Soil and Water Assessment Tool (SWAT) to evaluate impacts of increased atmospheric CO2 concentration and potential climate change on the water cycle and nitrogen loads in the semiarid James River Basin (JRB) in the Midwestern United States. We assessed responses of water yield, soil water content, groundwater recharge, and nitrate nitrogen (NO3–N) load under hypothetical climate-sensitivity scenarios in terms of CO2, precipitation, and air temperature. We extended our predictions of the dynamics of these hydrological variables into the mid-21st century with downscaled climate projections integrated across output from six General Circulation Models. Our simulation results compared against the baseline period 1980 to 2009 suggest the JRB hydrological system is highly responsive to rising levels of CO2 concentration and potential climate change. Under our scenarios, substantial decrease in precipitation and increase in air temperature by the mid-21st century could result in significant reduction in water yield, soil water content, and groundwater recharge. Our model also estimated decreased NO3–N load to streams, which could be beneficial, but a concomitant increase in NO3–N concentration due to a decrease in streamflow likely would degrade stream water and threaten aquatic ecosystems. These results highlight possible risks of drought, water supply shortage, and water quality degradation in this basin.

  8. Projection of climate change and its impact on the hydrological regimes of the Vistula and the Odra watersheds as the two major river basins in Poland.

    Science.gov (United States)

    Piniewski, Mikołaj; Mezghani, Abdelkader; Szcześniak, Mateusz; Berezowski, Tomasz; Kardel, Ignacy; Okruszko, Tomasz; Dobler, Andreas; Kundzewicz, Zbigniew

    2016-04-01

    Water resources management and associated hydrological risks require a reliable characterisation of hydrological behaviour under historical and future climate conditions. Even under the historical climate conditions, it is difficult to estimate the natural variability of hydrological regimes. We propose high-resolution simulations of natural daily streamflow for the period 1951-2013 in a dense network of river reaches of the transboundary Vistula and Odra basins occupying 313,000 km2, using SWAT model. The SWAT model is calibrated on a gridded daily (minimum and maximum) temperature and precipitation dataset (5 km resolution) developed, for this purpose, for the entire study area based on kriging technique (DOI 10.4121/uuid:e939aec0-bdd1-440f-bd1e-c49ff10d0a07). After validating the SWAT model in reproducing key observed hydrological features in a set of 80 relatively unimpaired sub-catchments, nine hydrological projections are produced where gridded meteorological variables as inputs in SWAT are replaced with meteorological variables from nine GCM-RCM runs projected to the year 2100 for RCP 4.5 provided within the EURO-CORDEX experiment. We will first present a comparison of the performance of the hydrological SWAT model driven by GCM-RCM runs for the historical period using both bias-corrected and raw GCM-RCM output variables. A particular interest will be on how well reproduced are meteorological extremes. Then, we will present the ability of the combined simulation approach to reproduce reliable change of key hydrological variables and especially extreme floods at different spatial scales of the catchments. Finally, hydrological projections under future climate conditions and their impacts on the Odra and Vistula river basins are analysed and discussed. Acknowledgements. Support of the project CHASE-PL (Climate change impact assessment for selected sectors in Poland) of the Polish-Norwegian Research Programme is gratefully acknowledged.

  9. The potential impact of an inter-basin water transfer project on nutrients (nitrogen and phosphorous) and chlorophyll a of the receiving water system.

    Science.gov (United States)

    Zeng, Qinghui; Qin, Lihuan; Li, Xuyong

    2015-12-01

    Any inter-basin water transfer project would cause complex physical, chemical, hydrological and biological changes to the receiving system. The primary channel of the middle route of the South-to-North Water Transfer Project has a total length of 1267 km. There is a significant difference between the physical, chemical and biological characteristics of the originating and receiving drinking water conservation districts. To predict the impacts of this long-distance inter-basin water transfer project on the N&P (nitrogen and phosphorus) concentrations and eutrophication risk of the receiving system, an environmental fluid dynamics code (EFDC) model was applied. The calibrated model accurately reproduced the hydrodynamic, water quality and the entire algal bloom process. Thirteen scenarios were defined to fully understand the N&P and chlorophyll a (Chl a) variation among different hydrological years, different quantity and timing of water transfer, and different inflows of N&P concentrations. The results showed the following: (a) The water transfer project would not result in a substantial difference to the trophic state of the Miyun reservoir in any of the hydrological years. (b) The area affected by the water transfer did not involve the entire reservoir. To minimize the impact of water transfer on N&P nutrients and Chl a, water should be transferred as uniform as possible with small discharge. (c) The variation in Chl a was more sensitive to an increase in P than an increase in N for the transferred water. The increased percentages of the average Chl a concentration when water was transferred in the spring, summer and autumn were 7.76%, 16.67% and 16.45%. Our findings imply that special attention should be given to prevent P increment of the transferred water from May to October to prevent algal blooms. The results provide useful information for decision makers about the quantity and timing of water transfers.

  10. Impacts of Climate Change and of Anthropisation on Water Resources: from the Risk Assessment to Adaptation, the Case of the Seine Basin (including Paris, France)

    Science.gov (United States)

    Habets, F.; Viennot, P.; Thierion, C.; Vergnes, J. P.; Ait Kaci, A.; Caballero, Y.

    2015-12-01

    The Seine river, located in the temperate climate of northern France and flowing over a large sedimentary basins that hosts multilayer aquifers, is characterized by small temporal variations of its discharge. However, the presence of a megacity (Paris) and a wide area of intensive agriculture combined with climate change puts pressure on the water resources both in terms of quality and quantity. Previous research projects have estimated the impact of climate change on the water resource of the Seine basin, with the uncertainties associated to climate projections, hydrological models or downscaling methods. The water resource was projected to decrease by -14 % ± 10 % in 2050 and -28 +/-16% in 2100. This led to new studies that focus on the combined impact of climate change and adaptations. The tested adaptations are: a reduction of the groundwater abstractions, evolution of land use, development of small dams to « harvest water » or artificial recharge of aquifers. The communication of the results of these projects to stakeholders have led to the development on new indicators that better express the risk on the water resource management, especially for the groundwater. For instance maps of the evolution of piezometric head are difficult to interpret. To better express the risk evolution, a new indicator was defined: the evolution of the groundwater crisis duration, ie, the period when the charge of the aquifer is below the crisis piezometric level defined by the stakeholders. Such crisis piezometric levels are used to help defining the period when the groundwater abstraction should be reduced. Such maps are more efficient to communicate with water resources managers. This communication will focus on the results from the MEDDE Explore 2070 and ANR Oracle projects.

  11. Impacts of climate change on the seasonality of low flows in 134 catchments in the river Rhine basin using an ensemble of bias-corrected regional climate simulations. Discussion paper

    NARCIS (Netherlands)

    Demirel, M.C.; Booij, M.J.; Hoekstra, A.Y.

    2013-01-01

    The impacts of climate change on the seasonality of low flows are analysed for 134 sub-catchments covering the River Rhine basin upstream of the Dutch–German border. Three seasonality indices for low flows are estimated, namely seasonality ratio (SR), weighted mean occurrence day (WMOD) and weighted

  12. Economic Impacts of Total Water Use Control in the Heihe River Basin in Northwestern China—An Integrated CGE-BEM Modeling Approach

    Directory of Open Access Journals (Sweden)

    Na Li

    2015-03-01

    Full Text Available This paper develops an integrated modeling approach combined with a top-down dynamic computable general equilibrium (CGE model and a bottom-up bio-economic model (BEM to study the economic impact of a total water use control policy in the Heihe river basin, northwestern China. The integrated CGE-BEM model is regionally disaggregated with a variety of crops and livestock, and includes the responses of farmers and consequent feedback effects in the regional economic system. The results show that under the total water use control scenario, the water use structure is changed and water use efficiency is improved. The total water use control policy has limited negative impact on the regional economic growth with only a slightly lower growth rate of 13.38% compared with a growth rate of 14% by 2020 under a business as usual water use scenario. However, the total water use control policy has significant negative impacts on several sectors, especially agriculture and food processing. It is expected cropping systems will change through a replacement of water-intensive crops with water-efficient crops. Farmers’ incomes will decrease by 3.14%. In order to alleviate farmers’ income loss and deal with water use conflicts across different sectors and regions, the promotion of migration of surplus labor from agriculture to non-agricultural sectors and the improvement of water use efficiency in agriculture are needed.

  13. Predicting impacts of increased CO{sub 2} and climate change on the water cycle and water quality in the semiarid James River Basin of the Midwestern USA

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yiping, E-mail: ywu@usgs.gov [ASRC Research and Technology Solutions, contractor to the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center, Sioux Falls, SD 57198 (United States); Liu, Shuguang, E-mail: sliu@usgs.gov [U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center, Sioux Falls, SD 57198 (United States); Geographic Information Science Center of Excellence, South Dakota State University, Brookings, SD 57007 (United States); Gallant, Alisa L., E-mail: gallant@usgs.gov [U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center, Sioux Falls, SD 57198 (United States); Geographic Information Science Center of Excellence, South Dakota State University, Brookings, SD 57007 (United States)

    2012-07-15

    Emissions of greenhouse gases and aerosols from human activities continue to alter the climate and likely will have significant impacts on the terrestrial hydrological cycle and water quality, especially in arid and semiarid regions. We applied an improved Soil and Water Assessment Tool (SWAT) to evaluate impacts of increased atmospheric CO{sub 2} concentration and potential climate change on the water cycle and nitrogen loads in the semiarid James River Basin (JRB) in the Midwestern United States. We assessed responses of water yield, soil water content, groundwater recharge, and nitrate nitrogen (NO{sub 3}-N) load under hypothetical climate-sensitivity scenarios in terms of CO{sub 2}, precipitation, and air temperature. We extended our predictions of the dynamics of these hydrological variables into the mid-21st century with downscaled climate projections integrated across output from six General Circulation Models. Our simulation results compared against the baseline period 1980 to 2009 suggest the JRB hydrological system is highly responsive to rising levels of CO{sub 2} concentration and potential climate change. Under our scenarios, substantial decrease in precipitation and increase in air temperature by the mid-21st century could result in significant reduction in water yield, soil water content, and groundwater recharge. Our model also estimated decreased NO{sub 3}-N load to streams, which could be beneficial, but a concomitant increase in NO{sub 3}-N concentration due to a decrease in streamflow likely would degrade stream water and threaten aquatic ecosystems. These results highlight possible risks of drought, water supply shortage, and water quality degradation in this basin. - Highlights: Black-Right-Pointing-Pointer We used a modified version of SWAT to more accurately simulate the effects of CO{sub 2}. Black-Right-Pointing-Pointer Our sensitivity analysis indicated this basin is very responsive to climate change. Black

  14. Climate change, land use and land cover change detection and its impact on hydrological hazards and sustainable development: a case study of Alaknanda river basin, Uttarakhand, India.

    Directory of Open Access Journals (Sweden)

    ABHAY SHANKAR PRASAD

    2017-05-01

    Full Text Available Extreme climatic events impact on the natural ecosystems of Alaknanda river basin which affect the socio-economic condition of the rural communities, loss of life, livelihood and natural resources. They pose a serious threat to normal life as well as the process of sustainable development. Rivers are fragile ecosystems which are globally important as water tower of the earth, reservoirs of rich biodiversity, and a popular destination for recreation, tourism and culture heritage. Rivers provides direct life support base for humankind. The unique Geo-climatic condition of Garhwal Himalaya, Alaknanda River basin, Uttarakhand makes it one of the most vulnerable regions in the India. Hydrological hazards are sudden calamities, which involve loss of life, property and livelihood. This paper presents a methodological approach for the integration of extreme events, climatic vulnerability, land use scenario, and flood risk assessment. Anthropogenic activities are continuously disturbing the natural system of the Garhwal Himalaya and its impact on extreme hydrological events. Factors causing these changes have been attempted to be understood through the use of GIS and Geospatial techniques. Human interference, unscientific developmental activities, agriculture extension, tourism activity and road construction are creating the hydrological hazards. Soil erosion and landslide have been recognised as major hazards in the high altitude region of Himalaya. This paper has analysed and evaluates the climate and livelihood vulnerability assessment and its adaptation for sustainable development in the near district headquarter (NDH away district headquarter (ADH determined mainly by a weighted matrix index. The Geospatial technique is used to find out the land use/cover change detection and secondary data is taken to carry out the analysis work. Primary data from each hotspot has been collected through a questionnaire survey and a Participatory Research Approach

  15. Allozyme relationships in hypostomines (Teleostei: Loricariidae) from the Itaipu Reservoir, Upper Rio Paraná basin, Brazil.

    Science.gov (United States)

    Zawadzki, Cláudio Henrique; Renesto, Erasmo; dos Reis, Roberto Esser; Moura, Maurício Osvaldo; Mateus, Rogério Pincela

    2005-03-01

    In an allozyme electrophoresis survey of 15 hypostomine species from the Itaipu Hydroelectric Reservoir, 25 loci from 14 enzyme systems were scored. Allozyme data allowed recording diagnostic genetic markers for all species analyzed and for some species groups within Hypostomus, a taxon which is taxonomically still unresolved in the Upper Rio Paraná basin. The mean expected heterozygosity of the species was considerably variable and hypotheses to tentatively explain this variation are discussed. A cladogram based upon the allelic frequencies of the species analyzed was produced by the continuous maximum likelihood method: Rhinelepis aspera and M. parananus were separated from the species of Hypostominae by a long branch length. Pterygoplichthys anisitsi was the sister of all the representatives of the genus Hypostomus. Within Hypostomus, two main clades were produced: in the first, H. cochliodon was the sister of the species comprising the H. plecostomus group, and in the second, the tree showed the following relationships: (H. albopunctatus (H. regani + Hypostomus sp. 3) + (H. margaritifer (H. microstomus (Hypostomus sp. 1 (H. ternetzi + Hypostomus sp. 2)). Hypostomus ternetzi and Hypostomus sp. 2 are referred to here as representatives of the H. ternetzi group.

  16. Stream-piracy impact on the long-term evolution of the Meuse basin. Physical approach "modeling with GOLEM"

    Science.gov (United States)

    Benaichouche, A.; Stab, O.; Cojan, I.; Brulhet, J.; Tijani, M.; Tessier, B.

    2012-04-01

    Landscape evolution results of antagonistic processes. In the Paris basin (France): tectonic uplift seems to be globally balanced by river incision. But the dynamic equilibrium of the relief can be disturbed by other processes and singularities may appear. A remarkable example is observed in the Meuse basin (NE of France), where the river is actually perched at more than +50m above the surrounding valleys: the Marne valley to the west and the Moselle valley to the east. This special morphology is the result of several stream piracies (at the expense of the Meuse) which has interested numerous researchers since a long time (Davis 1895, Blache 1943, Lesson-Quinif 2001 & Le Roux Harmand 1997-2009…). The most important ones of these piracies are: 1) the well-known capture of the Haute-Moselle by a tributary of the Meurthe near Toul; 2) at the north-west, the capture of the river Aire by the Aisne. On-going evolution suggests that similar events can be expected in the long-term future. Where and when next streams piracies could occur, what consequences may be expected? Our approach is to simulate the dynamic evolution of the landscape with an improved version of GOLEM (Geomorphic / Orogenic Landscape Evolution Model - LEM), software developed by Tucker & Slingerland in 1994 (http://csdms.colorado.edu/wiki/Model:GOLEM). The LEM characterizes erosion by incorporating diffusion and advection equations whose parameters must be fixed, according to local conditions. First simulations for next millions years with « detachment-limited » mode, let us locate several potential captures of the Meuse river by tributaries of the Moselle, therefore inducing a complete reorganization of the hydrographic network. The results of the localizations agree with local topography/geometry analysis. The first capture induces the propagation of a knickpoint and a significant lowering of the upstream part of the Meuse's basin. Downstream of the capture, the orientation of the abandoned valley

  17. Impact of sewage treatment plants and combined sewer overflow basins on the microbiological quality of surface water.

    Science.gov (United States)

    Rechenburg, A; Koch, Ch; Classen, Th; Kistemann, Th

    2006-01-01

    In a small river catchment, microbiological quality of different sewage treatment plants under regular conditions and in case of heavy rainfall, when combined sewage overflow basins (CSOs) are activated, was examined regarding microbial indicators and pathogens. In the watercourse, no self-cleaning effects could be observed. Small compact treatment plants discharge treated wastewater with a poor microbiological quality compared to river water quality and the quality of treated wastewater of larger plants. During storm water events, concentrations of microorganisms downstream of sewer overflows were approximately two logs higher than during dry weather conditions. Concentrations of parasites decreased slowly during the overflow, in parallel to filterable matter and particle-bound substances. The annual load of microorganisms originating from CSOs significantly exceeds the load from treated effluent of the sewage plants. Thus, an improved hygienic quality of the water course could be achieved by preventing overflows and by enhancing sewage treatment plants.

  18. Physicochemical impacts of dust particles on alpine glacier meltwater at the Laohugou Glacier basin in western Qilian Mountains, China.

    Science.gov (United States)

    Dong, Zhiwen; Qin, Dahe; Chen, Jizu; Qin, Xiang; Ren, Jiawen; Cui, Xiaoqing; Du, Zhiheng; Kang, Shichang

    2014-09-15

    This work discusses the temporal variation of various physicochemical species in the meltwater runoff of Laohugou Glacier No. 12 (4260 ma.s.l.) in central Asia, and their correlation with dust particles, based on a two-year field observation in summer 2012 and 2013, mainly focusing on dust concentration and size distribution, meltwater chemistry, particles SEM-EDX analysis in the meltwater, and MODIS atmospheric optical depth fields around the Qilian Mountains in central Asia. We find that, the volume-size distribution of dust particles in the meltwater is mainly composed of three parts, which includes fine aerosol particles (with diameter of 0~3.0 μm, mainly PM 2.5), atmospheric dust (with diameter of 3.0~20 μm), and local dust particles (20~100 μm), respectively. Comparison of dust particles in the snowpack and meltwater runoff indicates that, large part of dust particles in the meltwater may have originated from atmospheric dust deposition to the snow and ice on the glacier, and transported into the meltwater runoff. Moreover, temporal variation of dust and major ions (especially crustal species) is very similar with each other, showing great influence of dust particles to the chemical constituents of the glacier meltwater. SPM and TDS implied significant influences of dust to the physical characteristics of the glacier meltwater. Results showed that, accelerated glacier melting may affect physicochemical characteristics of the meltwater at an alpine basin under global warming. MODIS atmospheric optical depth (AOD) fields derived using the Deep Blue algorithm, showed great influence of regional dust transportation over western Qilian Mountains in springtime. SEM-EDX analysis shows that dust particles in the glacier meltwater contain Si-, Al-, Ca-, K-, and Fe-rich materials, such as quartz, albite, aluminate, and fly ash, similar to that deposited in snowpack. These results showed great and even currently underestimated influences of atmospheric dust

  19. Potential Impacts of Tsangpo Lake-Burst Megafloods and Their Preservation in the Bengal Basin and Delta System

    Science.gov (United States)

    Diamond, M. S.; Goodbred, S. L., Jr.; Palamenghi, L.; Hossain, S.; Pickering, J.; Sincavage, R.; Spiess, V.; Williams, L. A.

    2014-12-01

    Large, glacially-dammed lakes formed via the impoundment of the Tsangpo River in Tibet led to lake-burst floods during the late Pleistocene and at least two intervals in the early and late Holocene. We present the first critical examination of the potential effects that the Holocene lake drainages had on the downstream Bengal delta and their preservation in the geologic record. Based on stratigraphic evidence from cores drilled across the delta, digital elevation models, seismic data, and hydraulic flow calculations, we propose that lake-burst floods could be responsible for (a) triggering short-lived avulsion events of the Brahmaputra River into the Sylhet basin, (b) the formation of two apparent overflow channels on the Madhupur Terrace, and (c) the deposition of a large, mass transport deposit in the submarine Swatch of No Ground canyon system. Comparing the early and late Holocene events, we expect the distribution of the floodwaters and their deposits in the two intervals to differ sharply owing to major differences in flood volume and the paleotopography of the delta. Despite much higher discharge, the early Holocene floods were largely accommodated within the vast lowstand valley of the Brahmaputra, with some spillover into the Sylhet basin. In contrast, the late Holocene floods likely spread over a larger area due to the relatively even, low-gradient topography. Offshore, a 40 m thick chaotic, semi-transparent seismic facies observed in the canyon corresponds temporally with the early Holocene floods and is tentatively interpreted as a subaqueous debris flow generated by the flood pulse directed to the canyon via the lowstand river valley. We examine the theoretical preservation potential of rare flood events in light of signal shredding mechanisms to help explain why evidence of the larger, early Holocene floods is preserved whereas we have found no clear signal from the younger floods.

  20. Climate change impacts on continental weathering through the Middle Jurassic to Lower Cretaceous of Sverdrup Basin, Canadian Arctic

    Science.gov (United States)

    Galloway, Jennifer; Grasby, Stephen; Swindles, Graeme; Dewing, Keith

    2014-05-01

    Jurassic to Cretaceous strata of Sverdrup Basin, Canadian Arctic Archipelago, contain marine and non-marine successions that can be studied to reconstruct ancient paleoclimates and paleoenvironments that are poorly understood in high-latitude regions. We use element geochemistry integrated with palynology to study a continuous Aalenian to Albian-aged succession preserved in the Hoodoo Dome H-37 oil and gas well located on southern Ellef Ringnes Island near the centre of Sverdrup Basin. Cluster analysis (stratigraphically constrained incremental sum of squares; CONISS) is used to delineate four geochemical zones that are broadly coeval with major changes in palyno-assemblages interpreted to reflect changes in regional paleoclimate. Zone 1 (late Aalenian to Bathonian) is characterized by palynomorphs associated with humid and warm climate conditions. The chemical alteration index (CAI) is high in this interval, expected under this a humid and warm climate. A transition to a seasonally arid and warm climate occurred in the Bathonian and persisted until the Kimmeridgian or Valanginian (Zone 2). This interval is characterized by decreased chemical weathering, indicated by a drop in CAI. The onset of Zone 3 (Kimmeridgian or Valanginian to late Barremian or early Aptian) occurs during a transition to humid and cool climate conditions and is associated with a period of regional uplift and rifting. Zone 3 is marked by a substantial and progressive drop in CAI, indicating a transition from a weathering to transport-dominated system, possibly associated with landscape destabilization. Reduced tectonic activity in Zone 4 (early Aptian to early or mid Albian) shows a return to active chemical weathering, possibly associated with landscape stabilization, suggested by a continued increase in pollen from upland coniferous taxa. The geochemical and palynological records of Middle Jurassic to Lower Cretaceous strata of the Hoodoo Dome H-37 oil and gas well show close correlation

  1. Impacts of climate change on streamflows under RCP scenarios: A case study in Xin River Basin, China

    Science.gov (United States)

    Zhang, Yuqing; You, Qinglong; Chen, Changchun; Ge, Jing

    2016-09-01

    Researchers often examine hydro-climatological processes via Global Circulation Model (GCM) and hydrological model, which have been shown to benefit water resources management and prediction, especially at the basin scale. In this study, the Soil and Water Assessment Tool (SWAT) and Statistical Downscaling Method (SDSM) were integrated and applied to estimate streamflows in the Xin River Basin, China, based on climate change scenarios downscaled from different GCMs (BCC-CSM1.1, CanESM2, and NorESM1-M) under three Representative Concentration Pathways (RCPs). Results confirmed that the calibrated SWAT model accurately depicts hydrological processes features at daily, monthly, and yearly scales. Three GCMs based on the calibrated SDSM showed that temperature is continually increasing in the region, however, future precipitation is highly complex and uncertain; there were significant differences among various GCM RCP scenarios. The average of the precipitation in three models showed slight and steady increase trends under RCP2.6 and RCP4.5, but a significant increase under the RCP8.5 scenario. The ensemble average of streamflow in GCMs demonstrated that many RCPs significantly decrease from May to June but increase from August to September relative to the baseline period. The ensemble mean of the multi-GCM indicated that future streamflows under RCP2.6 and RCP4.5 scenarios will be closer to the current streamflow volume. Many RCPs also revealed a significant increase in monthly streamflow dispersion coefficient in October, reflecting a tendency for drought and flood events in that month. The BCC-CSM1.1 and NorESM1-M models showed that streamflows are higher than the baseline with median probability in the future. The low monthly streamflow (10th percentile) processes for each GCM were altogether similar to the baseline, whereas the high monthly streamflows (90th percentile) showed various levels of disparity compared to the baseline.

  2. Direct and indirect economic impacts of drought in the agri-food sector in the Ebro River basin (Spain)

    Science.gov (United States)

    Gil, M.; Garrido, A.; Hernández-Mora, N.

    2013-10-01

    The economic evaluation of drought impacts is essential in order to define efficient and sustainable management and mitigation strategies. The aim of this study is to evaluate the economic impacts of a drought event on the agricultural sector and measure how they are transmitted from primary production to industrial output and related employment. We fit econometric models to determine the magnitude of the economic loss attributable to water storage. The direct impacts of drought on agricultural productivity are measured through a direct attribution model. Indirect impacts on agricultural employment and the agri-food industry are evaluated through a nested indirect attribution model. The transmission of water scarcity effects from agricultural production to macroeconomic variables is measured through chained elasticities. The models allow for differentiating the impacts deriving from water scarcity from other sources of economic losses. Results show that the importance of drought impacts are less relevant at the macroeconomic level, but are more significant for those activities directly dependent on water abstractions and precipitation. From a management perspective, implications of these findings are important to develop effective mitigation strategies to reduce drought risk exposure.

  3. Assessing the Utility of a Satellite-Based Flood Inundation and Socio-Economic Impact Tool for the Lower Mekong River Basin

    Science.gov (United States)

    Ahamed, A.; Bolten, J. D.

    2016-12-01

    Flood disaster events in Southeast Asia result in significant loss of life and economic damage. Remote sensing information systems designed to monitor floods and assess their severity can help governments and international agencies formulate an effective response before and during flood events, and ultimately alleviate impacts to population, infrastructure, and agriculture. Recent examples of destructive flood events in the Lower Mekong River Basin occurred in 2000, 2011, and 2013. Floods can be particularly costly in the developing countries of Southeast Asia where large portions of the population live on or near the floodplain (Jonkman, 2005; Kirsch et al., 2012; Long and Trong, 2001; Stromberg. 2007). Regional studies (Knox, 1993; Mirza, 2002; Schiermeier, 2011; Västilä et al, 2010) and Intergovernmental Panel on Climate Change (IPCC, 2007) projections suggest that precipitation extremes and flood frequency are increasing. Thus, improved systems to rapidly monitor flooding in vulnerable areas are needed. This study determines surface water extent for current and historic flood events by using stacks of historic multispectral Moderate-resolution Imaging Spectroradiometer (MODIS) 250-meter imagery and the spectral Normalized Difference Vegetation Index (NDVI) signatures of permanent water bodies (MOD44W). Supporting software tools automatically assess flood impacts to population and infrastructure to provide a rapid first set of impact numbers generated hours after the onset of an event. The near real-time component uses twice daily imagery acquired at 3-hour latency, and performs image compositing routines to minimize cloud cover. Case studies for historic flood events are presented. Results suggest that near real-time remote sensing-based observation and impact assessment systems can serve as effective regional decision support tools for governments, international agencies, and disaster responders.

  4. Environmental impact and magnitude of paleosol carbonate carbon isotope excursions marking five early Eocene hyperthermals in the Bighorn Basin, Wyoming

    Science.gov (United States)

    Abels, Hemmo A.; Lauretano, Vittoria; van Yperen, Anna E.; Hopman, Tarek; Zachos, James C.; Lourens, Lucas J.; Gingerich, Philip D.; Bowen, Gabriel J.

    2016-05-01

    Transient greenhouse warming events in the Paleocene and Eocene were associated with the addition of isotopically light carbon to the exogenic atmosphere-ocean carbon system, leading to substantial environmental and biotic change. The magnitude of an accompanying carbon isotope excursion (CIE) can be used to constrain both the sources and amounts of carbon released during an event and also to correlate marine and terrestrial records with high precision. The Paleocene-Eocene Thermal Maximum (PETM) is well documented, but CIE records for the subsequent warming events are still rare, especially from the terrestrial realm.Here, we provide new paleosol carbonate CIE records for two of the smaller hyperthermal events, I1 and I2, as well as two additional records of Eocene Thermal Maximum 2 (ETM2) and H2 in the Bighorn Basin, Wyoming, USA. Stratigraphic comparison of this expanded, high-resolution terrestrial carbon isotope history to the deep-sea benthic foraminiferal isotope records from Ocean Drilling Program (ODP) sites 1262 and 1263, Walvis Ridge, in the southern Atlantic Ocean corroborates the idea that the Bighorn Basin fluvial sediments record global atmospheric change. The ˜ 34 m thicknesses of the eccentricity-driven hyperthermals in these archives corroborate precession forcing of the ˜ 7 m thick fluvial overbank-avulsion sedimentary cycles. Using bulk-oxide mean-annual-precipitation reconstructions, we find soil moisture contents during the four younger hyperthermals that are similar to or only slightly wetter than the background, in contrast with soil drying observed during the PETM using the same proxy, sediments, and plant fossils.The magnitude of the CIEs in soil carbonate for the four smaller, post-PETM events scale nearly linearly with the equivalent event magnitudes documented in marine records. In contrast, the magnitude of the PETM terrestrial CIE is at least 5 ‰ smaller than expected based on extrapolation of the scaling relationship established

  5. Assessing the impact of hydrodynamics on large-scale flood wave propagation - a case study for the Amazon Basin

    Science.gov (United States)

    Hoch, Jannis M.; Haag, Arjen V.; van Dam, Arthur; Winsemius, Hessel C.; van Beek, Ludovicus P. H.; Bierkens, Marc F. P.

    2017-01-01

    Large-scale flood events often show spatial correlation in neighbouring basins, and thus can affect adjacent basins simultaneously, as well as result in superposition of different flood peaks. Such flood events therefore need to be addressed with large-scale modelling approaches to capture these processes. Many approaches currently in place are based on either a hydrologic or a hydrodynamic model. However, the resulting lack of interaction between hydrology and hydrodynamics, for instance, by implementing groundwater infiltration on inundated floodplains, can hamper modelled inundation and discharge results where such interactions are important. In this study, the global hydrologic model PCR-GLOBWB at 30 arcmin spatial resolution was one-directionally and spatially coupled with the hydrodynamic model Delft 3D Flexible Mesh (FM) for the Amazon River basin at a grid-by-grid basis and at a daily time step. The use of a flexible unstructured mesh allows for fine-scale representation of channels and floodplains, while preserving a coarser spatial resolution for less flood-prone areas, thus not unnecessarily increasing computational costs. In addition, we assessed the difference between a 1-D channel/2-D floodplain and a 2-D schematization in Delft 3D FM. Validating modelled discharge results shows that coupling PCR-GLOBWB to a hydrodynamic routing scheme generally increases model performance compared to using a hydrodynamic or hydrologic model only for all validation parameters applied. Closer examination shows that the 1-D/2-D schematization outperforms 2-D for r2 and root mean square error (RMSE) whilst having a lower Kling-Gupta efficiency (KGE). We also found that spatial coupling has the significant advantage of a better representation of inundation at smaller streams throughout the model domain. A validation of simulated inundation extent revealed that only those set-ups incorporating 1-D channels are capable of representing inundations for reaches below the

  6. Impact of Middle Eastern dust sources on PM10 in Iran: Highlighting the impact of Tigris-Euphrates basin sources and Lake Urmia desiccation

    Science.gov (United States)

    Sotoudeheian, Saeed; Salim, Reza; Arhami, Mohammad

    2016-12-01

    Contribution of different Middle Eastern dust origins to PM10 (PM with aerodynamic diameters less than 10 µm) levels in several receptor large cities in Iran was investigated. Initially, the major regional dust episodes were determined through statistical analysis of recorded PM levels at air quality stations and verified using satellite images. The particles dispersion was simulated by Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) to regenerate PM10 during the dust episodes. The accuracy of the modeled results was rather convincing, with an average squared correlation coefficient (R2) of 0.7 (max = 0.95). Consequently, the contributions of different dust sources to the observed concentrations were determined. Basin of Tigris-Euphrates Rivers encompasses active dust sources with significant rate of emission due to fluvial deposits. The sources in this basin with approximately 70-95% contribution, by far, had the most influence on PM10 levels at the receptor cities. In a finer resolution, northern and central parts of Iraq had the most influence on PM10 level during the dust episodes. Effect of probable improvement or deterioration of the current dust origin conditions on PM10 levels was analyzed by performing a sensitivity analysis through varying threshold friction velocities. The results demonstrated that 10% increase or decrease in threshold friction velocities of major dust sources could lead to average of 51% decrease or 77% increase in the receptor cities' PM10, respectively. Finally, effects of Lake Urmia desiccation, as a new hydrological prospect dust origin were analyzed. The predicted dust from the prospective dried lake bed could result in 30-60% increase in PM10 of nearby cities during the studied dust episodes.

  7. Institutions and Societal Impacts of Climate in the Lower Colorado and San Pedro Basins of the U.S.-Mexico Border Region

    Science.gov (United States)

    Varady, R. G.; Wilder, M.; Morehouse, B. J.; Garfin, G. M.

    2007-05-01

    The U.S. Southwest and Mexico border region feature two prominent river basins, the Colorado and Rio Grande, and ecologically important sub-basins such as the San Pedro. The area within which these transboundary basins lie is characterized by overall aridity and high climatic variability over seasonal to decadal and longer time scales. Throughout human occupation, numerous and diverse strategies for buffering climate impacts have emerged. The most notable response has been an increasingly complex system of institutions and structures designed to buffer water scarcity. The Colorado River Compact, and the laws governing allocation of waters from the Rio Grande River, together with the dams, hydropower generators, canals and other engineered features, represent two of the most complex systems. Drought nevertheless remains a looming specter across much of the binational border region. Institutional mechanisms for responding to drought range from awareness-raising and capacity-building efforts, to implementation of formal drought plans, to storing water to make up for deficits, and water conservation rules that become increasingly stringent as drought intensifies. A number of formal and informal binational institutions operate in the region. Some are venerable, like the century-old International Boundary and Water Commission (IBWC) and its Mexican counterpart the Comision Internacional de Limites y Agua (CILA). Others, like the Border Environment Cooperation Commission and the North American Development Bank, were created in the mid-1990s with the North American Free Trade Agreement. These institutions, both domestic and transnational, operate in a complex binational, bicultural environment with contrasting legal and administrative traditions. Under such constraints, they manage water resources and ecosystems and attempt to improve water and sanitation infrastructure in the context of deep and extended drought. But in spite of their efforts, society and natural habitat

  8. Combined impacts of current and future dust deposition and regional warming on Colorado River Basin snow dynamics and hydrology

    Science.gov (United States)

    Deems, Jeffrey S.; Painter, Thomas H.; Barsugli, Joseph J.; Belnap, Jayne; Udall, Bradley

    2013-01-01

    The Colorado River prov