WorldWideScience

Sample records for climate glacier mass

  1. Climate - glacier links on Bogerbreen, Svalbard : Glacier mass balance investigations in central Spitsbergen 2004 / 2005

    OpenAIRE

    2006-01-01

    Abstract Glaciers are key indicators for climate change. Mass balance studies form the important link between advances and retreats of glaciers to changes in climate. Mass balance studies were performed in the balance year 2004/05 on Bogerbreen as part of my Master thesis. Bogerbreen is a valley glacier with a size of 3.3 km² located in central Spitsbergen, Svalbard at 78 degrees north and 15 degrees east. The direct glaciological method was applied to measure winter mass balance using sno...

  2. The climatic mass balance of Svalbard glaciers: a 10-year simulation with a coupled atmosphere-glacier mass balance model

    Science.gov (United States)

    Aas, Kjetil S.; Dunse, Thorben; Collier, Emily; Schuler, Thomas V.; Berntsen, Terje K.; Kohler, Jack; Luks, Bartłomiej

    2016-05-01

    In this study we simulate the climatic mass balance of Svalbard glaciers with a coupled atmosphere-glacier model with 3 km grid spacing, from September 2003 to September 2013. We find a mean specific net mass balance of -257 mm w.e. yr-1, corresponding to a mean annual mass loss of about 8.7 Gt, with large interannual variability. Our results are compared with a comprehensive set of mass balance, meteorological, and satellite measurements. Model temperature biases of 0.19 and -1.9 °C are found at two glacier automatic weather station sites. Simulated climatic mass balance is mostly within about 100 mm w.e. yr-1 of stake measurements, and simulated winter accumulation at the Austfonna ice cap shows mean absolute errors of 47 and 67 mm w.e. yr-1 when compared to radar-derived values for the selected years 2004 and 2006. Comparison of modeled surface height changes from 2003 to 2008, and satellite altimetry reveals good agreement in both mean values and regional differences. The largest deviations from observations are found for winter accumulation at Hansbreen (up to around 1000 mm w.e. yr-1), a site where sub-grid topography and wind redistribution of snow are important factors. Comparison with simulations using 9 km grid spacing reveal considerable differences on regional and local scales. In addition, 3 km grid spacing allows for a much more detailed comparison with observations than what is possible with 9 km grid spacing. Further decreasing the grid spacing to 1 km appears to be less significant, although in general precipitation amounts increase with resolution. Altogether, the model compares well with observations and offers possibilities for studying glacier climatic mass balance on Svalbard both historically as well as based on climate projections.

  3. Glaciers in a changing global climate: first results of worldwide glacier mass balance measurements 2000/2001

    Science.gov (United States)

    Frauenfelder, R.; Hoelzle, M.; Haeberli, W.

    2003-04-01

    Glacier signals from mountain areas are key elements of early detection strategies for dealing with possible man-induced climate change. The IPCC Third Assessment Report indeed defines mountain glaciers as one of the best natural indicators of atmospheric warming with the highest reliability ranking. In the chain of processes linking climate and glacier fluctuations, glacier length variation is the indirect/delayed response, whereas glacier mass change is the direct/undelayed reaction. Internationally coordinated long-term monitoring of glaciers started in 1894. The responsibility to collect and publish standardized data has been assumed since 1986 by the World Glacier Monitoring Service (WGMS). This work is primarily being carried out under the auspices of the International Commission on Snow and Ice (ICSI/IAHS) and the Federation of Astronomical and Geophysical Services (FAGS/ICSU). The WGMS maintains data exchange with the ICSU World Data Center A (WDC-A) for Glaciology in Boulder, Colorado. Corresponding data bases and measurement networks form an essential part of the Global Terrestrial Network for Glaciers (GTN-G: operated by the WGMS) as a pilot project within the Global Terrestrial Observing System (GTOS/GCOS). A network of 60 glacier mass balance observations provides information on presently observed rates of change in glacier mass, corresponding acceleration trends and regional distribution patterns. A preliminary calculation of the mass balance observations in 2000/2001 relating to 23 selected data sets provide a mean specific (annual) net balance of -367 mm w.e., 26 % of the observed balances were positive. The corresponding mean in six mountain ranges was -571 mm w.e. Such values indicate that mass losses in 2000/2001 have been less extreme than in the extraordinary years before but are still strongly negative. Over the past two decades glacier melt appears to continue at a considerable and possibly even an accelerating rate. The observed average

  4. Mass Balance of a Maritime Glacier on the Southeast Tibetan Plateau and Its Climatic Sensitivity

    Science.gov (United States)

    Yang, W.

    2014-12-01

    Based on glacio-meteorological measurements and mass-balance stake records during the five-year period of 2005-2010 on the southeast Tibetan Plateau, an energy-mass balance model was applied to study the surface mass balance of the Parlung No. 94 Glacier, as well as its response to regional climate conditions. The primary physical parameters involved in the model were locally calibrated by using relevant glacio-meteorological datasets. The good agreement between the snowpack height/mass balance simulations and the in-situ measurements available from a total of 12 monitoring stakes over this glacier confirmed the satisfactory performance of the energy-mass balance model. Results suggested that the recent state of the Parlung No. 94 Glacier was far removed from the 'ideal' climatic regime leading to zero mass balance, with its annual mass balance of approximately -0.9 m w.e. during 2005-2010. Climatic sensitivity experiments were also carried out to interpret the observed mass-balance changes, and the experiments demonstrated that the maritime glaciers concerned herein were theoretically more vulnerable to ongoing climate warming on the Tibetan Plateau than potential changes in the amount of precipitation. A plausible causal explanation for the recent glacier shrinkage in this region was concerned with the increasing air temperature. Moreover, both the mass balance simulations and the field measurements indicated that the mass accumulation over this maritime glacier occurred primarily in the boreal spring. Such "spring-accumulation type" glaciers are presumed to be distributed mainly within a narrow wedge-shaped region along the Brahmaputra River. Climatic sensitivities of the glacier mass balanceare also found to be closely linked to the regional precipitation seasonality that is simultaneously modulated by various atmospheric circulation patterns, such as the southern westerlies, the Bay of Bengal vortex in the spring season and the Indian monsoon in the summer

  5. Modelled mass balance of Xibu glacier, Tibetan Plateau: sensitivity to climate change

    OpenAIRE

    Caidong, Caidong; Sorteberg, Asgeir

    2010-01-01

    Due to a lack of in situ measurements, model-based studies of glacier mass balance in the Tibetan Plateau are very limited. An energy-balance model is applied to analyse the mass-balance sensitivity of Xibu glacier, in the Nyainqêntanglha mountain range, to climatic change. A sensitivity calculation shows that a temperature change of ±1°C or a precipitation change of ±35% changes the equilibrium-line altitude (ELA) by 140±125 m. We use a clustering method to link local weather parameter...

  6. Climate, glacier mass balance and runoff (1993-2005) for the Mittivakkat Glacier catchment, Ammassalik Island, SE Greenland, and in a long term perspective (1898-1993)

    DEFF Research Database (Denmark)

    Mernild, Sebastian H.; Kane, D.L.; Hansen, Birger;

    2008-01-01

    Climate, glacier mass balance and runoff are investigated in the Low-Arctic Mittivakkat Glacier catchment on Ammassalik Island, Southeast Greenland. High-resolution meteorological data from the catchment covering 1993-2005 and standard synoptic meteorological data from the nearby town of Tasiilaq....... The calculated glacier net mass balance indicates an average glacier loss of 550±530 mm w.eq. yr-1, and 89 out of 105 mass balance years show a negative net mass balance. For the 106-yr period average runoff was estimated to be 1957±254 mm w.eq. yr-1.......Climate, glacier mass balance and runoff are investigated in the Low-Arctic Mittivakkat Glacier catchment on Ammassalik Island, Southeast Greenland. High-resolution meteorological data from the catchment covering 1993-2005 and standard synoptic meteorological data from the nearby town of Tasiilaq...... temperatures (MAAT) occur in the coastal area, indicating an approximately 20-d shorter thawing period. The higher lying glacier area, in contrast, experiences an increasing MAAT, an approximately 40-d longer thawing period and a 60-d longer snow-free period. The Mittivakkat Glacier net mass balance has been...

  7. Climatic Forcing of Glacier Surface Mass Balance Changes Along North-Central Peru: A Modeling Perspective

    Science.gov (United States)

    Mark, B. G.; Fernandez, A.

    2015-12-01

    Most tropical glaciers are Peru, where they are key water sources for communities in mountain environments and beyond. Thus, their sustained shrinkage portrays these glaciers as archetype of global warming impacts on the local scale. However, there is still no deep understanding on the mechanism connecting temperature and these glaciers. Among others, the effect of temperature on the glacier surface mass balance (GSMB) can be expressed within accumulation regimes and hence in surface albedo, or in ablation dynamics through incoming longwave energy (LE). Here, we report a study combining statistical analyses of reanalysis data (~30km grid-cell), regional climate modeling and glacier mass balance simulations at high resolution (2km) to analyze long-term (30 years) and seasonal GSMB along north-central Peru. Our goal is to mechanistically understand climate change impact on these glaciers. Results suggest temperature as the main factor controlling GSMB changes through the lapse rate (LR). Correlations of GSMB with LR, humidity and zonal wind point to vertical homogenization of temperature, causing LE to increase, despite this flux always remaining negative. This "less negative" LE multiplies the impact of the seasonal fluctuation in albedo, thereby enhancing total ablation. As this mechanism only needs a relative increase in temperature, it may even occur in subfreezing conditions. Model output also indicates that turbulent fluxes are small, largely cancelling out. This suggests that the impact of LE is more likely to occur compared to either turbulent fluxes changes or shifts in the proportion of sublimation versus melt, which we find to be regionally stable. These findings imply that glaciers in north-central Peru are sensitive to subtle changes in temperature. We discuss the implications for process-based understanding and how this non-linear and somewhat hidden effect of temperature reduces the skill of temperature index models to simulate GSMB in the Tropics.

  8. Surface melt dominates Alaska glacier mass balance

    Science.gov (United States)

    Larsen Chris F; Burgess, E; Arendt, A.A.; O'Neel, Shad; Johnson, A.J.; Kienholz, C.

    2015-01-01

    Mountain glaciers comprise a small and widely distributed fraction of the world's terrestrial ice, yet their rapid losses presently drive a large percentage of the cryosphere's contribution to sea level rise. Regional mass balance assessments are challenging over large glacier populations due to remote and rugged geography, variable response of individual glaciers to climate change, and episodic calving losses from tidewater glaciers. In Alaska, we use airborne altimetry from 116 glaciers to estimate a regional mass balance of −75 ± 11 Gt yr−1 (1994–2013). Our glacier sample is spatially well distributed, yet pervasive variability in mass balances obscures geospatial and climatic relationships. However, for the first time, these data allow the partitioning of regional mass balance by glacier type. We find that tidewater glaciers are losing mass at substantially slower rates than other glaciers in Alaska and collectively contribute to only 6% of the regional mass loss.

  9. Sensitivity of annual mass balance gradient and Hypsometry to the changing climate: the case of Dokriani Glacier, central Himalaya, India

    Science.gov (United States)

    Pratap, B.

    2015-12-01

    The glacier mass balance is undelayed, unfiltered and direct method to assess the impact of climate change on the glaciers. Many studies suggest that some of the Himalayan glaciers have lost their mass at an increased rate during the past few decades. Furthermore, the mass balance gradient and hypsometric analysis are important to understand the glacier response towards climatic perturbations. Our long term in-situ monitoring on the Dokriani Glacier provides great insights to understand the variability in central Himalayan glaciers. We report the relationship between glacier hypsometry and annual mass balance gradient (12 years) to understand the glacier's response towards climate change. Dokriani Glacier in the Bhagirathi basin is a small (7 km2) NNW exposed glacier in the western part of central Himalaya, India. The study analysed the annual balance, mass balance gradient and length changes observed during first decade of 21st century (2007-2013) and compare with the previous observations of 1990s (1992-2000). A large spatial variability in the mass balance gradients of two different periods has been observed. The equilibrium-line altitude (ELA) was fluctuated between 5000 and 5100 m a.s.l. and the derived time averaged ELA (ELAn) and balance budget ELA (ELA0) were 5075 and 4965 m a.s.l respectively during 1992-2013. The observed time-averaged accumulation-area ratio (AARn) and balance budget AAR (AAR0) were 0.67 and 0.72 respectively during 1992-2013. The higher value of AAR comprises due to flat and broader accumulation area (4.50 km2) of the glacier. Although, having larger accumulation area, the glacier has faced strong mass wasting with average annual ablation of -1.82 m w.e. a-1 in the ablation zone as compare to residual average annual accumulation of 0.41 m w.e. a-1. Based on the annual mass balance series (12 years) Dokriani Glacier has continuous negative annual balances with monotonically negative cumulative mass loss of -3.86 m w.e with the average

  10. Reconstructing glacier mass balances in the Central Andes of Chile and Argentina using local and regional hydro-climatic data

    Directory of Open Access Journals (Sweden)

    M. H. Masiokas

    2015-09-01

    Full Text Available Despite the great number and variety of glaciers in southern South America, in situ glacier mass balance records are extremely scarce and glacier–climate relationships are still poorly understood in this region. Here we use the longest (> 35 years and most complete in situ mass balance record, available for glaciar Echaurren Norte in the Andes at ~34° S, to develop a minimal glacier surface mass balance model that relies on nearby monthly precipitation and air temperature data as forcing. This basic model is able to explain 78 % of the variance in the annual glacier mass balance record over the 1978–2013 calibration period. An attribution assessment indicates that precipitation variability constitutes the most important forcing modulating annual glacier mass balances at this site. A regionally-averaged series of mean annual streamflow records from both sides of the Andes is then used to estimate, through simple linear regression, this glacier's annual mass balance variations since 1909. The reconstruction model captures 68 % of the observed glacier mass balance variability and shows three periods of sustained positive mass balances embedded in an overall negative trend totaling almost −42 m w.eq. over the past 105 years. The three periods of sustained positive mass balances (centered in the 1920s–1930s, in the 1980s and in the first decade of the 21st century coincide with several documented glacier advances in this region. Similar trends observed in other shorter glacier mass balance series suggest the glaciar Echaurren Norte reconstruction is representative of larger-scale conditions and could be useful for more detailed glaciological, hydrological and climatological assessments in this portion of the Andes.

  11. The Orographic Climate Factors Contributing to the Mass Balance of Small Glaciers in North-Iceland

    OpenAIRE

    Halkola, Kaisa

    2005-01-01

    This report is a result of a master thesis project. The project was launched to get more information of the factors affecting the mass balance of small glaciers in Northern Iceland. Observations on the glaciers were analysed in comparison with previous estimations of mass balance (Eythorsson and Sigtryggsson, 1971), a degree-day mass-balance model (MBT) and an atmospheric model MM5 (National Centre for Atmospheric Research (NCAR) / Pennsylvania State University).

  12. Simulating the climatic mass balance of Svalbard glaciers from 2003 to 2013 with a high-resolution coupled atmosphere-glacier model

    Directory of Open Access Journals (Sweden)

    K. S. Aas

    2015-10-01

    Full Text Available In this study we simulate the climatic mass balance of Svalbard glaciers with a coupled atmosphere-glacier model with 3 km grid spacing, from September 2003 to September 2013. We find a mean specific net mass balance of −167 mm w.e. yr−1, corresponding to a mean annual mass loss of about 5.7 Gt, with large interannual variability. Our results are compared with a comprehensive set of mass balance, meteorological and satellite measurements. Model temperature biases of 0.17 and −1.9 °C are found at two glacier automatic weather station sites. Simulated climatic mass balance is mostly within about 0.1 m w.e. yr−1 of stake measurements, and simulated winter accumulation at the Austfonna ice cap shows mean absolute errors of 0.05 and 0.06 m w.e. yr−1 when compared to radar-derived values for the selected years 2004 and 2006. Comparison of surface height changes from 2003 to 2008 from model, and satellite altimetry reveals good agreement in both mean values and regional differences. The largest deviations from observations are found for winter accumulation at Hansbreen (up to around 1 m w.e. yr−1, a site where sub-grid topography and wind redistribution of snow are important factors. Comparison with simulations using a 9 km grid spacing reveal considerable differences on regional and local scales. In addition, the 3 km grid spacing allows for a much more detailed comparison with observations than what is possible with a 9 km grid spacing. Further decreasing the grid spacing to 1 km appears to be less significant, although in general precipitation amounts increase with resolution. Altogether, the model compares well with observations and offers possibilities for studying glacier climatic mass balance on Svalbard both historically as well as based on climate projections.

  13. Reanalysing glacier mass balance measurement series

    OpenAIRE

    Zemp, M.; E. Thibert; Huss, M.; Stumm, D.; Rolstad Denby, C.; Nuth, C.; S. U. Nussbaumer; G. Moholdt; A. Mercer; Mayer, C.; Joerg, P. C.; P. Jansson; B. Hynek; Fischer, A.; Escher-Vetter, H.

    2013-01-01

    Glacier-wide mass balance has been measured for more than sixty years and is widely used as an indicator of climate change and to assess the glacier contribution to runoff and sea level rise. Until recently, comprehensive uncertainty assessments have rarely been carried out and mass balance data have often been applied using rough error estimation or without consideration of errors. In this study, we propose a framework for reanalysing glacier mass balance series that includes conceptual and ...

  14. Insight into glacier climate interaction: reconstruction of the mass balance field using ice extent data

    Science.gov (United States)

    Visnjevic, Vjeran; Herman, Frédéric; Licul, Aleksandar

    2016-04-01

    With the end of the Last Glacial Maximum (LGM), about 20 000 years ago, ended the most recent long-lasting cold phase in Earth's history. We recently developed a model that describes large-scale erosion and its response to climate and dynamical changes with the application to the Alps for the LGM period. Here we will present an inverse approach we have recently developed to infer the LGM mass balance from known ice extent data, focusing on a glacier or ice cap. The ice flow model is developed using the shallow ice approximation and the developed codes are accelerated using GPUs capabilities. The mass balance field is the constrained variable defined by the balance rate β and the equilibrium line altitude (ELA), where c is the cutoff value: b = max(βṡ(S(z) - ELA), c) We show that such a mass balance can be constrained from the observed past ice extent and ice thickness. We are also investigating several different geostatistical methods to constrain spatially variable mass balance, and derive uncertainties on each of the mass balance parameters.

  15. Glacier volume response time and its links to climate and topography based on a conceptual model of glacier hypsometry

    OpenAIRE

    Raper, S.C.B.; R. J. Braithwaite

    2009-01-01

    Glacier volume response time is a measure of the time taken for a glacier to adjust its geometry to a climate change. It has been previously proposed that the volume response time is given approximately by the ratio of glacier thickness to ablation at the glacier terminus. We propose a new conceptual model of glacier hypsometry (area-altitude relation) and derive the volume response time where climatic and topographic parameters are separated. The former is expressed by mass balance gradients...

  16. Stationary monitoring of glacier response to climate change in China

    Science.gov (United States)

    Ren, Jiawen; Li, Zhongqin; Qin, Xiang; He, Yuanqing; He, Xiaobo; Li, Huilin

    2016-04-01

    At present, there are about 48571 glaciers with a total area of about 51.8×103 km2 and a volume of about 5.6×103 km3 in China. They are distributed widely in the high mountains in and surrounding the Tibetan Plateau and other high mountains such as Tianshan, Altay and Pamir. In view of differences in climatic conditions and glacier types, stationary monitoring of the glacier variations has been ongoing in different regions in order to investigate the glacier response to climate change. The monitoring results show that all the monitoring glaciers have been in retreat during the past decades and especially since 1990's the retreat rate has an accelerating trend. The accumulative mass balance is much negative and has a large annual variability for the monsoonal maritime glaciers in comparison with the continental and sub-continental glaciers. Under climate warming background, the acceleration of glacier melting is mainly attributed to rise in air temperature, ice temperature augment and albedo reduction of glacier surface. Particularly, the albedo reduction has a positive feedback effect on the glacier melting. Based on long term observation of glacier variations and physical properties, a simple dynamics model is coupled with mass balance modeling to make a projection of a typical glacier change in future. The primary modeling results suggest that the glacier will continue in shrinkage until vanishing within 50-90 years.

  17. Uncertainties and re-analysis of glacier mass balance measurements

    OpenAIRE

    Zemp, M.; E. Thibert; Huss, M.; Stumm, D.; Rolstad Denby, C.; Nuth, C.; S. U. Nussbaumer; G. Moholdt; A. Mercer; Mayer, C.; Joerg, P. C.; P. Jansson; B. Hynek; Fischer, A.; Escher-Vetter, H.

    2013-01-01

    Glacier-wide mass balance has been measured for more than sixty years and is widely used as an indicator of climate change and to assess the glacier contribution to runoff and sea level rise. Until present, comprehensive uncertainty assessments have rarely been carried out and mass balance data have often been applied using rough error estimation or without error considerations. In this study, we propose a framework for re-analyzing glacier mass balance series including conceptual and ...

  18. On the response of valley glaciers to climatic change

    NARCIS (Netherlands)

    Oerlemans, J.

    1989-01-01

    In many cases the response of a glacier to changing climatic conditions is complicated due to the large number of feedback loops that play a role. Examples are: ice thickness - mass balance feedback, nonlinearities arising from complicated geometry, dependence of ablation on glacier geometry, coupli

  19. Hypsometric control on glacier mass balance sensitivity in Alaska

    Science.gov (United States)

    McGrath, D.; Sass, L.; Arendt, A. A.; O'Neel, S.; Kienholz, C.; Larsen, C.; Burgess, E. W.

    2015-12-01

    Mass loss from glaciers in Alaska is dominated by strongly negative surface balances, particularly on small, continental glaciers but can be highly variable from glacier to glacier. Glacier hypsometry can exert significant control on mass balance sensitivity, particularly if the equilibrium line altitude (ELA) is in a broad area of low surface slope. In this study, we explore the spatial variability in glacier response to future climate forcings on the basis of hypsometry. We first derive mass balance sensitivities (30-70 m ELA / 1° C and 40-90 m ELA / 50% decrease in snow accumulation) from the ~50-year USGS Benchmark glaciers mass balance record. We subsequently assess mean climate fields in 2090-2100 derived from the IPCC AR5/CMIP5 RCP 6.0 5-model mean. Over glaciers in Alaska, we find 2-4° C warming and 10-20% increase in precipitation relative to 2006-2015, but a corresponding 0-50% decrease in snow accumulation due to rising temperatures. We assess changes in accumulation area ratios (AAR) to a rising ELA using binned individual glacier hypsometries. For an ELA increase of 150 m, the mean statewide AAR drops by 0.45, representing a 70% reduction in accumulation area on an individual glacier basis. Small, interior glaciers are the primary drivers of this reduction and for nearly 25% of all glaciers, the new ELA exceeds the glacier's maximum elevation, portending eventual loss. The loss of small glaciers, particularly in the drier interior of Alaska will significantly modify streamflow properties (flashy hydrographs, earlier and reduced peak flows, increased interannual variability, warmer temperatures) with poorly understood downstream ecosystem and oceanographic impacts.

  20. The influence of changes in glacier extent and surface elevation on modeled mass balance

    OpenAIRE

    Paul, F.

    2010-01-01

    Glaciers are widely recognized as unique demonstration objects for climate change impacts, mostly due to the strong change of glacier length in response to small climatic changes. However, glacier mass balance as the direct response to the annual atmospheric conditions can be better interpreted in meteorological terms. When the climatic signal is deduced from long-term mass balance data, changes in glacier geometry (i.e. surface extent and elevation) must be considered as such adjustments ...

  1. Glacier and climate change in Pakistan and Afghanistan

    Science.gov (United States)

    Shroder, J.; Bishop, M.; Burgett, A.

    2012-04-01

    Climate change predictions and water resource related issuesin Afghanistan and Pakistan have led to the need for detailed assessments and understanding of glacier fluctuations, and the determination of the dominant controlling factors governing glacier sensitivity to climate change. Consequently, we studied glacier fluctuations and the role of topography in an attempt to understand glacier fluctuations.Specifically we used ASTER imagery, Landsat ETM data, and an SRTM digital elevation model, together with Google Earth™ high-resolution imagery to examine terminus fluctuations, ice velocity variations, and local- and meso-scale topographic parameters that are related to irradiance variations, ablation, and glacial geomorphology.Multispectral satellite imagery were utilized to estimate advance and retreat rates, along with glacier profile velocities. Geomorphometric analysis was utilized to generateglacier altitude profiles of hypsometry, slope, curvature, and topographic shielding. Our results reveal that glacier response to climate change is highly variable in Pakistan, as many glaciers are advancing as well as retreating, while others exhibit a stationary terminus. It is important to note that advances in the Karakoram do not appear to be restricted to glaciers at high elevations, suggesting climate forcing. Glaciers in the Hindu Raj and Hindu Kush are retreating, with fewer glaciers advancing, indicating the possibility of a spatial trend from West to East in Pakistan. There is a dramatic diminution of Hindu Kush ice in Afghanistan. In the Karakoram, many new surging glaciers have been identified with flow velocities ranging from 200-1000 m/yr. Non- surging glaciers also exhibit relative high velocities there. Spatial patternsof relief appear to be associated with glacier debris cover, as snow/ice avalanchescontribute debris and ice mass. In addition, patterns of topographic shielding are highly variable, revealing variations in the diffuse-skylight irradiance

  2. Glacier volume response time and its links to climate and topography based on a conceptual model of glacier hypsometry

    Directory of Open Access Journals (Sweden)

    S. C. B. Raper

    2009-03-01

    Full Text Available Glacier volume response time is a measure of the time taken for a glacier to adjust its geometry to a climate change. It is currently believed that the volume response time is given approximately by the ratio of glacier thickness to ablation at the glacier terminus. We propose a new conceptual model of glacier hypsometry (area-altitude relation and derive the volume response time where climatic and topographic parameters are separated. The former is expressed by mass balance gradients which we derive from glacier-climate modelling and the latter are quantified with data from the World Glacier Inventory. Aside from the well-known scaling relation between glacier volume and area, we establish a new scaling relation between glacier altitude range and area, and evaluate it for seven regions. The presence of this scaling parameter in our response time formula accounts for the mass balance elevation feedback and leads to longer response times than given by the simple ratio of glacier thickness to ablation. Volume response times range from decades to thousands of years for glaciers in maritime (wet-warm and continental (dry-cold climates, respectively. The combined effect of volume-area and altitude-area scaling relations is such that volume response time can increase with glacier area (Axel Heiberg Island and Svalbard, hardly change (Northern Scandinavia, Southern Norway and the Alps or even get smaller (The Caucasus and New Zealand.

  3. Glacier volume response time and its links to climate and topography based on a conceptual model of glacier hypsometry

    Directory of Open Access Journals (Sweden)

    S. C. B. Raper

    2009-08-01

    Full Text Available Glacier volume response time is a measure of the time taken for a glacier to adjust its geometry to a climate change. It has been previously proposed that the volume response time is given approximately by the ratio of glacier thickness to ablation at the glacier terminus. We propose a new conceptual model of glacier hypsometry (area-altitude relation and derive the volume response time where climatic and topographic parameters are separated. The former is expressed by mass balance gradients which we derive from glacier-climate modelling and the latter are quantified with data from the World Glacier Inventory. Aside from the well-known scaling relation between glacier volume and area, we establish a new scaling relation between glacier altitude range and area, and evaluate it for seven regions. The presence of this scaling parameter in our response time formula accounts for the mass balance elevation feedback and leads to longer response times than given by the simple ratio of glacier thickness to ablation at the terminus. Volume response times range from decades to thousands of years for glaciers in maritime (wet-warm and continental (dry-cold climates respectively. The combined effect of volume-area and altitude-area scaling relations is such that volume response time can increase with glacier area (Axel Heiberg Island and Svalbard, hardly change (Northern Scandinavia, Southern Norway and the Alps or even get smaller (The Caucasus and New Zealand.

  4. The response of glaciers to climate change

    NARCIS (Netherlands)

    Klok, Elisabeth Jantina

    2003-01-01

    The research described in this thesis addresses two aspects of the response of glaciers to climate change. The first aspect deals with the physical processes that govern the interaction between glaciers and climate change and was treated by (1) studying the spatial and temporal variation of the glac

  5. A GRASS GIS module to obtain an estimation of glacier behavior under climate change: A pilot study on Italian glacier

    Science.gov (United States)

    Strigaro, Daniele; Moretti, Massimiliano; Mattavelli, Matteo; Frigerio, Ivan; Amicis, Mattia De; Maggi, Valter

    2016-09-01

    The aim of this work is to integrate the Minimal Glacier Model in a Geographic Information System Python module in order to obtain spatial simulations of glacier retreat and to assess the future scenarios with a spatial representation. The Minimal Glacier Models are a simple yet effective way of estimating glacier response to climate fluctuations. This module can be useful for the scientific and glaciological community in order to evaluate glacier behavior, driven by climate forcing. The module, called r.glacio.model, is developed in a GRASS GIS (GRASS Development Team, 2016) environment using Python programming language combined with different libraries as GDAL, OGR, CSV, math, etc. The module is applied and validated on the Rutor glacier, a glacier in the south-western region of the Italian Alps. This glacier is very large in size and features rather regular and lively dynamics. The simulation is calibrated by reconstructing the 3-dimensional dynamics flow line and analyzing the difference between the simulated flow line length variations and the observed glacier fronts coming from ortophotos and DEMs. These simulations are driven by the past mass balance record. Afterwards, the future assessment is estimated by using climatic drivers provided by a set of General Circulation Models participating in the Climate Model Inter-comparison Project 5 effort. The approach devised in r.glacio.model can be applied to most alpine glaciers to obtain a first-order spatial representation of glacier behavior under climate change.

  6. Reconstruction of Glacier Mass Balance and Sensitivity Tests to Climate Change: A case study of Ålfotbreen and Nigardsbreen

    OpenAIRE

    Wangdui, Wangdui

    2011-01-01

    A physically-based one dimensional CROCUS snow model was applied to simulate the surface mass balances of Ålfotbreen (1964-2009) and Nigardsbreen (1962-2009) in southern Norway. The required hourly meteorological input data (9 parameters) are obtained from daily data of meteorological observation from stations surrounding the glaciers combined with NCEP 6 hourly reanalysis data to get the diurnal cycle. The results of simulations show that the model was able to simulate the mass balance of Ål...

  7. What influences climate and glacier change in southwestern China?

    Science.gov (United States)

    Yasunari, Teppei J.

    2011-12-01

    The subject of climate change in the Tibetan Plateau (TP) and Himalayas has taken on increasing importance because of the availability of water resources from their mountain glaciers (Immerzeel et al 2010). Many of the glaciers over these regions have been retreating, while some are advancing and stable (Yao et al 2004, Scherler et al 2011). Other studies report that some glaciers in the Himalayas show acceleration of their shrinkage (e.g., Fujita and Nuimura 2011). However, the causes of glacier melting are still difficult to grasp because of the complexity of climatic change and its influence on glacier issues. Despite this, it is vital that we pursue further study to enable future predictions of glacier changes. The paper entitled 'Climate and glacier change in southwestern China during the past several decades' by Li et al (2011) provided carefully analyzed, quality controlled, long-term data on atmospheric temperature and precipitation during the period 1961-2008. The data were obtained from 111 Chinese stations. The researchers performed systematic analyses of temperature and precipitation over the whole southwestern Chinese domain. They discussed those changes in terms of other meteorological components such as atmospheric circulation patterns, radiation and altitude difference, and then showed how these factors could contribute to climate and glacier changes in the region. Air temperature and precipitation are strongly associated with glacier mass balance because of heat balance and the addition of mass when it snows. Temperature warming trends over many places in southwestern China were unequivocally dominant in all seasons and at higher altitudes. This indicates that the heat contribution to the glaciers has been increasing. On the other hand, precipitation has a wider variability in time and space. It is more difficult to clearly understand the effect of precipitation on the climate and glacier melting characteristics in the whole of southwestern China

  8. Tropical glaciers and climate dynamics: Resolving the linkages

    Science.gov (United States)

    Mölg, Thomas

    2013-04-01

    Large-scale atmosphere/ocean circulation and mountain glaciers represent two entirely different scales in the climate system. Therefore, statistical linkages between the two mask a cascade of processes that act on different temporal and spatial dimensions. Low-latitude glaciers are particularly well suited for studying such processes, since these glaciers are situated in the "heart" of the global climate system (the tropics). This presentation gives an overview of a decade of research on tropical climate and glaciers on Kilimanjaro (East Africa), which is, to our knowledge, the only case where space/time linkages between high-altitude glaciers and climate dynamics have been investigated systematically throughout the main scales. This includes the complex modification of atmospheric flow when air masses impinge on high mountains, an aspect that has been widely neglected from a cryospheric viewpoint. The case of Kilimanjaro demonstrates (1) the great potential of learning about climate system processes and their connections, (2) advances in our understanding of the importance of moisture for glaciers that lie far above the mean freezing level, and (3) methodological advances in combining atmospheric and cryospheric modelling.

  9. Climate Change and Glacier Retreat: Scientific Fact and Artistic Opportunity

    Science.gov (United States)

    Fagre, D. B.

    2008-12-01

    Mountain glaciers continue to retreat rapidly over most of the globe. In North America, at Glacier National Park, Montana, recent research results from Sperry Glacier (2005-2007) indicate negative mass balances are now 3-4 times greater than in the 1950s. A geospatial model of glacier retreat in the Blackfoot-Jackson basin suggested all glaciers would be gone by 2030 but has proved too conservative. Accelerated glacier shrinkage since the model was developed has mirrored an increase in actual annual temperature that is almost twice the rate used in the model. The glaciers in Glacier National Park are likely to be gone well before 2030. A variety of media, curricula, and educational strategies have been employed to communicate the disappearance of the glaciers as a consequence of global warming. These have included everything from print media and television coverage to podcasts and wayside exhibits along roads in the park. However, a new thrust is to partner with artists to communicate climate change issues to new audiences and through different channels. A scientist-artist retreat was convened to explore the tension between keeping artistic products grounded in factually-based reality while providing for freedom to express artistic creativity. Individual artists and scientists have worked to create aesthetic and emotional images, using painting, poetry, music and photography, to convey core messages from research on mountain ecosystems. Finally, a traveling art exhibit was developed to highlight the photography that systematically documents glacier change through time. The aim was to select photographs that provide the most compelling visual experience for an art-oriented viewer and also accurately reflect the research on glacier retreat. The exhibit opens on January 11, 2009

  10. USGS Alaska Benchmark Glacier Mass Balance Data - Phase 1; Gulkana and Wolverine Glaciers

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Since the late 1950s, USGS has maintained a long-term glacier mass-balance program at three North American glaciers. Similar measurements began at Sperry Glacier,...

  11. North Cascade Glacier Annual Mass Balance Record Analysis 1984-2013

    Science.gov (United States)

    Pelto, M. S.

    2014-12-01

    The North Cascade Glacier Climate Project (NCGCP) was founded in 1983 to monitor 10 glaciers throughout the range and identify their response to climate change. The annual observations include mass balance, terminus behavior, glacier surface area and accumulation area ratio (AAR). Annual mass balance (Ba) measurements have been continued on the 8 original glaciers that still exist. Two glaciers have disappeared: the Lewis Glacier and Spider Glacier. In 1990, Easton Glacier and Sholes Glacier were added to the annual balance program to offset the loss. One other glacier Foss Glacier has declined to the extent that continued measurement will likely not be possible. Here we examine the 30 year long Ba time series from this project. All of the data have been reported to the World Glacier Monitoring Service (WGMS). This comparatively long record from glaciers in one region conducted by the same research program using the same methods offers some useful comparative data. Degree day factors for melt of 4.3 mm w.e.°C-1d-1 for snow and 6.6 mm w.e.°C-1d-1 for ice has been determined from 412 days of ablation observation. The variation in the AAR for equilibrium Ba is small ranging from 60 to 67. The mean annual balance of the glaciers from 1984-2013 is -0.45 ma-1, ranging from -0.31 to -0.57 ma-1 for individual glacier's. The correlation coefficient of Ba is above 0.80 between all glaciers including the USGS benchmark glacier, South Cascade Glacier. This indicates that the response is to regional climate change, not local factors. The mean annual balance of -0.45 ma-1 is close to the WGMS global average for this period -0.50 ma-1. The cumulative loss of 13.5 m w.e. and 15 m of ice thickness represents more than 20% of the volume of the glaciers.

  12. Climatic controls and climate proxy potential of Lewis Glacier, Mt Kenya

    Science.gov (United States)

    Prinz, Rainer; Nicholson, Lindsey; Gurgiser, Wolfgang; Mölg, Thomas; Kaser, Georg

    2016-04-01

    Glaciers in the tropics can provide information about regional climate, its dynamics, and its evolution over decadal and centennial time scales, if their interaction with the atmosphere is understood, and their changes are documented or reconstructed. The glaciers on Mount Kenya capture a climate signal from the mid troposphere at about 5 km a.s.l., where our knowledge of climate change is scarce and controversial. We use in-situ meteorological and glaciological observations to optimize and validate a physically-based, process-orientated energy and mass balance model to quantify the exchange processes between the glacier surface and the atmosphere above and to explore the sensitivity of energy and mass exchanges to changing climatic conditions. Currently the glacier loses mass due to the imbalance between insufficient accumulation and enhanced melt, because radiative energy gains cannot be compensated by turbulent energy sinks. Exchanging model input data with synthetic climate scenarios, which were sampled from the meteorological measurements and account for coupled climatic variable perturbations, reveal that the current mass balance is most sensitive to changes in atmospheric moisture (via its impact on solid precipitation, cloudiness and surface albedo). Scenarios with lower air temperatures are drier and associated with lower accumulation and increased net radiation due to reduced cloudiness and albedo. Hence, similar to the glaciers of nearby Kilimanjaro, the recession of Lewis Glacier is not because of increased air temperatures, but because of decreased atmospheric moisture. If the climate scenarios currently producing positive mass balances are applied to Lewis Glacier's late 19th century maximum extent (L19), negative mass balances are the result, meaning that the conditions required sustaining the glacier in its L19 extent are not reflected in today's climate observations. Alternatively, a balanced mass budget for the L19 extent can be explained by

  13. Ideal climatic variables for the present-day geometry of the Gregoriev Glacier, Inner Tien Shan, Kyrgyzstan, derived from GPS data and energy-mass balance measurements

    Directory of Open Access Journals (Sweden)

    K. Fujita

    2011-03-01

    Full Text Available We conducted 2 yr (2005–2007 of in situ meteorological and glaciological observations on the Gregoriev Glacier, a flat-top glacier within the Inner Tien Shan, Kyrgyzstan. Differential GPS surveys reveal a vertical surface deletion at the summit of the glacier. Based on snow density data and an energy-mass balance model, we estimate that the annual precipitation and summer mean temperature required to maintain the glacier in the modern state are 289 mm and −3.85 °C at the glacier summit (4600 m above sea level, a.s.l., respectively. The good agreement between the long-term estimated and observed precipitation at a nearby station in the Tien Shan (292 mm at 3614 m a.s.l. for the period 1930–2002 suggests that the glacier dynamics have been regulated by the long-term average accumulation. The glacier mass-balance, reconstructed based on meteorological data from the Tien Shan station for the past 80 yr, explains the observed fluctuations in glacier extent, particularly the negative mass balance in the 1990s.

  14. An improved technique for the reconstruction of former glacier mass-balance and dynamics

    Science.gov (United States)

    Carr, Simon; Coleman, Christopher

    2007-11-01

    The recognition of past glacier extent and dynamics is a fundamental aspect of investigations of the climatic sensitivity of glaciers, especially when examining short-lived climate events such as the Younger Dryas or Little Ice Age. Existing approaches to the reconstruction of glacier form and dynamics depend on speculative reasoning of key glacier dynamic parameters, including the role of basal slip and subglacial deformation in glacier mass-transfer. This study reviews approaches to glacier reconstruction, derivation of former glacier equilibrium line altitudes (ELA's) and estimation of mass-balance and dynamics, concluding that most reconstructions of glacier mass-balance are compromised by a lack of glaciological considerations. An alternative approach to glacier reconstruction is presented, demonstrated and discussed, by which an empirical relationship between ablation gradient and mass loss at the ELA is used to derive mass-balance, mass-flux through the ELA and average balance velocity at the ELA. This 'glaciological' approach is applied to four reconstructed glaciers to test previous interpretations that each reflects Younger Dryas glaciation in the UK. The study concludes that this approach provides a more robust technique for reconstructing former glacier dynamics, and may be applied to test geomorphological interpretations of former mountain glaciation.

  15. Quick ice mass loss and abrupt retreat of the maritime glaciers in the Kangri Karpo Mountains, southeast Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    YANG Wei; YAO TanDong; XU BaiQing; WU GuangJian; MA LingLong; XIN XiaoDong

    2008-01-01

    The maritime glaciers are sensitive to climate change because of high annual precipitation and high air temperature in the region.A combined comprehensive study was carried out based on glacier mass balance observation,GPS-based glacier terminus position survey,glacier Ground Penetrating Radar,topography maps and RS satellite images in the Kangri Karpo Mountains,Southeast Tibet.The study revealed a strong ice mass loss and quick glacier retreat since the 1970s.Ata Glacier,one glacier from the south slope of the Kangri Karpo Mountains,has formed a 6-km-long terminal moraine zone at the end of the glacier since the 1970s,and the accelerating retreat is largely due to the strong glacier sur-face melting.Mass balance study on the other four glaciers on the northern side of the Kangri Karpo Mountains shows that they are in large negative mass balance and the glaciers had retreated 15-19 m from May 2006 to May 2007.The in-situ glacier observation also shows that the glacier retreat is more obvious in small glaciers.The enhanced ice mass deficit caused by climate warming and the ongoing extinction of many small glaciers in this region could seriously affect the water resources,environ-ments,local climate and regional sustainable development in the near future.

  16. Mass balance investigation of alpine glaciers through LANDSAT TM data

    Science.gov (United States)

    Bayr, Klaus J.

    1989-01-01

    An analysis of LANDSAT Thematic Mapper (TM) data of the Pasterze Glacier and the Kleines Fleisskees in the Austrian Alps was undertaken and compared with meteorological data of nearby weather stations. Alpine or valley glaciers can be used to study regional and worldwide climate changes. Alpine glaciers respond relatively fast to a warming or cooling trend in temperature through an advance or a retreat of the terminus. In addition, the mass balance of the glacier is being affected. Last year two TM scenes of the Pasterze Glacier of Aug. 1984 and Aug. 1986 were used to study the difference in reflectance. This year, in addition to the scenes from last year, one MSS scene of Aug. 1976 and a TM scene from 1988 were examined for both the Pasterze Glacier and the Kleines Fleisskees. During the overpass of the LANDSAT on 6 Aug. 1988 ground truthing on the Pasterze Glacier was undertaken. The results indicate that there was considerable more reflectance in 1976 and 1984 than in 1986 and 1988. The climatological data of the weather stations Sonnblick and Rudolfshuette were examined and compared with the results found through the LANDSAT data. There were relations between the meteorological and LANDSAT data: the average temperature over the last 100 years showed an increase of .4 C, the snowfall was declining during the same time period but the overall precipitation did not reveal any significant change over the same period. With the use of an interactive image analysis computer, the LANDSAT scenes were studied. The terminus of the Pasterze Glacier retreated 348 m and the terminus of the Kleines Fleisskees 121 m since 1965. This approach using LANDSAT MSS and TM digital data in conjunction with meteorological data can be effectively used to monitor regional and worldwide climate changes.

  17. The influence of changes in glacier extent and surface elevation on modeled mass balance

    Directory of Open Access Journals (Sweden)

    F. Paul

    2010-12-01

    Full Text Available Glaciers are widely recognized as unique demonstration objects for climate change impacts, mostly due to the strong change of glacier length in response to small climatic changes. However, glacier mass balance as the direct response to the annual atmospheric conditions can be better interpreted in meteorological terms. When the climatic signal is deduced from long-term mass balance data, changes in glacier geometry (i.e. surface extent and elevation must be considered as such adjustments form an essential part of the glacier reaction to new climatic conditions. In this study, a set of modelling experiments is performed to assess the influence of changes in glacier geometry on mass balance for constant climatic conditions. The calculations are based on a simplified distributed energy/mass balance model in combination with information on glacier extent and surface elevation for the years 1850 and 1973/1985 for about 60 glaciers in the Swiss Alps. The results reveal that over this period about 50–70% of the glacier reaction to climate change (here a one degree increase in temperature is "hidden" in the geometric adjustment, while only 30–50% can be measured as the long-term mean mass balance. For larger glaciers, the effect of the areal change is partly reduced by a lowered surface elevation, which results in a slightly more negative balance despite a potential increase of topographic shading. In view of several additional reinforcement feedbacks that are observed in periods of strong glacier decline, it seems that the climatic interpretation of long-term mass balance data is rather complex.

  18. The influence of changes in glacier extent and surface elevation on modeled mass balance

    Directory of Open Access Journals (Sweden)

    F. Paul

    2010-06-01

    Full Text Available Glaciers are widely recognized as unique demonstration objects for climate change impacts, mostly due to the strong change of glacier length in response to small climatic changes. However, glacier mass balance as the direct response to the annual atmospheric conditions can be better interpreted in meteorological terms. When the climatic signal is deduced from long-term mass balance data, changes in glacier geometry (i.e. surface extent and elevation must be considered as such adjustments form an essential part of the glacier reaction to new climatic conditions. In this study, a set of modeling experiments is performed to assess the influence of changes in glacier geometry on mass balance for constant climatic conditions. The calculations are based on a simplified distributed energy/mass balance model in combination with information on glacier extent and surface elevation for the years 1850 and 1973/1985 for a larger sample of glaciers in the Swiss Alps. The results reveal that about 50–70% of the glacier reaction to climate change (here a one degree increase in temperature is "hidden" in the geometric adjustment, while only 30–50% can be measured as the long-term mean mass balance. Thereby, changes in glacier extent alone have an even stronger effect, but they are partly compensated for by a lowered surface elevation which gives on average a slightly more negative balance despite an increase of topographic shading. In view of several additional reinforcement feedbacks that are observed in periods of strong glacier decline, it seems that the climatic interpretation of mass balance data is also rather complex.

  19. Climatic controls on the pace of glacier erosion

    Science.gov (United States)

    Koppes, Michele; Hallet, Bernard; Rignot, Eric; Mouginot, Jeremie; Wellner, Julia; Love, Katherine

    2016-04-01

    Mountain ranges worldwide have undergone large-scale modification due the erosive action of ice, yet the mechanisms that control the timing of this modification and the rate by which ice erodes remain poorly understood. Available data report a wide range of erosion rates from individual ice masses over varying timescales, suggesting that modern erosion rates exceed orogenic rates by 2-3 orders of magnitude. These modern rates are presumed to be due to dynamic acceleration of the ice masses during deglaciation and retreat. Recent numerical models have focused on replicating the processes that produce the geomorphic signatures of glacial landscapes. Central to these models is a simple quantitative index that relates erosion rate to ice dynamics and to climate. To provide such an index, we examined explicitly the factors controlling modern glacier erosion rates across climatic regimes. Holding tectonic history, bedrock lithology and glacier hypsometries relatively constant across a latitudinal transect from Patagonia to the Antarctic Peninsula, we find that modern, basin-averaged erosion rates vary by three orders of magnitude, from 1->10 mm yr-1 for temperate tidewater glaciers to 0.01-ELA, in accord with theory. The general relationship between ice dynamics and erosion suggests that the erosion rate scales non-linearly with basal sliding speed, with an exponent n ≈ 2-2.62. Notably, erosion rates decrease by over two orders of magnitude between temperate and polar glaciers with similar ice discharge rates. The difference in erosion rates between temperate and colder glaciers of similar shape and size is primarily related to the abundance of meltwater accessing the bed. Since all glaciers worldwide have experienced colder than current climatic conditions, the 100-fold decrease in long-term relative to modern erosion rates may in part reflect the temporal averaging of warm and cold-based conditions over the lifecycle of these glaciers. Higher temperatures and

  20. What Influences Climate and Glacier Change in the Southwestern China?

    Science.gov (United States)

    Yasunari, Teppei J.

    2012-01-01

    The subject of climate change in the areas of the Tibetan Plateau (TP) and the Himalayas has taken on increasing importance because of available water resources from their mountain glaciers. Many of these glaciers over the region have been retreating, while some are advancing and stable. Other studies report that some glaciers in the Himalayas show acceleration on their shrinkage. However, the causes of the glacier meltings are still difficult to grasp because of the complexity of climatic change and its influence on glacier issues. However, it is vital that we pursue further study to enable the future prediction on glacier changes.

  1. Climatic controls and climate proxy potential of Lewis Glacier, Mt Kenya

    Directory of Open Access Journals (Sweden)

    R. Prinz

    2015-07-01

    Full Text Available The Lewis Glacier on Mt Kenya is one of the best studied tropical glaciers and has experienced considerable retreat since a maximum extent in the late 19th century (L19. From distributed mass and energy balance modelling, this study evaluates the current sensitivity of the surface mass and energy balance to climatic drivers, explores climate conditions under which the L19 maximum extent might have sustained, and discusses the potential for using the glacier retreat to quantify climate change. Multiyear meteorological measurements at 4828 m provide data for input, optimization and evaluation of a spatially distributed glacier mass balance model to quantify the exchanges of energy and mass at the glacier–atmosphere interface. Currently the glacier loses mass due to the imbalance between insufficient accumulation and enhanced melt, because radiative energy gains cannot be compensated by turbulent energy sinks. Exchanging model input data with synthetic climate scenarios, which were sampled from the meteorological measurements and account for coupled climatic variable perturbations, reveal that the current mass balance is most sensitive to changes in atmospheric moisture (via its impact on solid precipitation, cloudiness and surface albedo. Positive mass balances result from scenarios with an increase of annual (seasonal accumulation of 30 % (100 %, compared to values observed today, without significant changes in air temperature required. Scenarios with lower air temperatures are drier and associated with lower accumulation and increased net radiation due to reduced cloudiness and albedo. If the scenarios currently producing positive mass balances are applied to the L19 extent, negative mass balances are the result, meaning that the conditions required to sustain the glacier in its L19 extent are not reflected in today's observations. Alternatively, a balanced mass budget for the L19 extent can be explained by changing model parameters that imply

  2. Climate change and tropical Andean glaciers : past, present and future

    OpenAIRE

    Vuille, M.; Francou, Bernard; Wagnon, Patrick; I. Juen; G. Kaser; Mark, B G; Bradley, R.S.

    2008-01-01

    Observations on glacier extent from Ecuador, Peru and Bolivia give a detailed and unequivocal account of rapid shrinkage of tropical Andean glaciers since the Little Ice Age (LIA). This retreat however, was not continuous but interrupted by several periods of stagnant or even advancing glaciers, most recently around the end of the 20th century. New data from mass balance networks established on over a dozen glaciers allows comparison of the glacier behavior in the inner and outer tropics. It ...

  3. Mass balance of the Lambert Glacier basin, East Antarctica

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Since it is the largest glacier system in Antarctica, the Lambert Glacier basin plays an important role in the mass balance of the overall Antarctic ice sheet. The observed data and shallow core studies from the inland traverse investigations in recent years show that there are noticeable differences in the distribution and variability of the snow accumulation rate between east and west sides. On the east side, the accumulation is higher on the average and has increased in the past decades, while on the west side it is contrary. The ice movement measurement and the ice flux calculation indicate that the ice velocity and the flux are larger in east than in west, meaning that the major part of mass supply for the glacier is from the east side. The mass budget estimate with the latest data gives that the integrated accumulation over the upstream area of the investigation traverse route is larger than the outflow ice flux by 13%, suggesting that the glacier basin is in a positive mass balance state and the ice thickness will increase if the present climate is keeping.

  4. Mass-balance parameters derived from a synthetic network of mass-balance glaciers

    OpenAIRE

    Machguth, Horst; Haeberli, Wilfried; Paul, Frank

    2012-01-01

    Glacier mass-balance parameters such as the equilibrium-line altitude (ELA) play an important role when working with large glacier samples. While the number of observational mass-balance series to derive such parameters is limited, more and more modeled data are becoming available. Here we explore the possibilities of analyzing such ‘synthetic’ mass-balance data with respect to mass-balance parameters. A simplified energy-balance model is driven by bias-corrected regional climate model output...

  5. Glacier mass-balance fluctuations in the Pacific Northwest and Alaska, USA

    Science.gov (United States)

    Josberger, E.G.; Bidlake, W.R.; March, R.S.; Kennedy, B.W.

    2007-01-01

    The more than 40 year record of net and seasonal mass-balance records from measurements made by the United States Geological Survey on South Cascade Glacier, Washington, and Wolverine and Gulkana Glaciers, Alaska, shows annual and interannual fluctuations that reflect changes in the controlling climatic conditions at regional and global scales. As the mass-balance record grows in length, it is revealing significant changes in previously described glacier mass-balance behavior, and both inter-glacier and glacier-climate relationships. South Cascade and Wolverine Glaciers are strongly affected by the warm and wet maritime climate of the northeast Pacific Ocean. Their net balances have generally been controlled by winter accumulation, with fluctuations that are strongly related to the Pacific Decadal Oscillation (PDO). Recently, warm dry summers have begun to dominate the net balance of the two maritime glaciers, with a weakening of the correlation between the winter balance fluctuations and the PDO. Non-synchronous periods of positive and negative net balance for each glacier prior to 1989 were followed by a 1989-2004 period of synchronous and almost exclusively negative net balances that averaged -0.8 m for the three glaciers.

  6. Glacier mass-balance fluctuations in the Pacific Northwest and Alaska, USA

    Science.gov (United States)

    Josberger, Edward G.; Bidlake, William R.; March, Rod S.; Kennedy, Ben W.

    2007-10-01

    The more than 40 year record of net and seasonal mass-balance records from measurements made by the United States Geological Survey on South Cascade Glacier, Washington, and Wolverine and Gulkana Glaciers, Alaska, shows annual and interannual fluctuations that reflect changes in the controlling climatic conditions at regional and global scales. As the mass-balance record grows in length, it is revealing significant changes in previously described glacier mass-balance behavior, and both inter-glacier and glacier-climate relationships. South Cascade and Wolverine Glaciers are strongly affected by the warm and wet maritime climate of the northeast Pacific Ocean. Their net balances have generally been controlled by winter accumulation, with fluctuations that are strongly related to the Pacific Decadal Oscillation (PDO). Recently, warm dry summers have begun to dominate the net balance of the two maritime glaciers, with a weakening of the correlation between the winter balance fluctuations and the PDO. Non-synchronous periods of positive and negative net balance for each glacier prior to 1989 were followed by a 1989-2004 period of synchronous and almost exclusively negative net balances that averaged -0.8 m for the three glaciers.

  7. Simulating the evolution of Himalayan glaciers with the regional climate model REMO

    Science.gov (United States)

    Kumar, P.; Kotlarski, S.; Sieck, K.; Frey, H.; Stoffel, M.; Jacob, D.

    2012-12-01

    The regional climate model REMO extended by a recently developed glacier parameterization scheme has been applied over the South Asian Himalayan mountain range. The glacier scheme interactively simulates the mass balance as well as changes of the areal extent of glaciers on a sub-grid scale. Various observational data sets, in particular a regional glacier inventory, have been compiled and were used to initialize glacier area and volume in the year 1989. A simulation for the period 1989-2008 using the ECMWF reanalysis as atmospheric boundary forcing was carried out. Preliminary results show a simulated decrease of glacier area of about 22% between 1989 and 2008. In contrast, the total ice volume in the model domain is showing an overall increase. This is due to the fact that several heavily glaciated grid cells experience a strong snow accumulation, which is subsequently turned into glacier ice and thereby increases the total ice volume. The major part of the simulation domain, however, experiences a strong decrease of both glacier area and glacier volume. Areas with local increases in glacier area and volume are found in the northern part of the model domain, in the Karakoram ranges and in some parts of the Kashmir Great Himalayan ranges. This feature is in good agreement with reported observations. Our results indicate that observed glacier changes can be approximately reproduced within a regional climate model based on simplified concepts of glacier-climate interaction. This, in turn, underlines the general applicability of the model system for scenarios of 21st century climate and glacier change.

  8. Mass balance gradients and climatic change

    OpenAIRE

    Oerlemans, J.; Hoogendoorn, N.C.

    1989-01-01

    It is generally assumed that the mass-balance gradient on glaciers is more or less conserved under climatic change. In studies of the dynamic response of glaciers to climatic change, one of the following assumptions is normally made: (i) the mass-balance perturbation is independent of altitude or (ii) the mass-balance profile does not change - it simply shifts up and down. Observational evidence for such an approach is not convincing; on some glaciers the inter-annual changes in mass balance ...

  9. Glacier and hydrology changes in future climate over western Canada

    Science.gov (United States)

    Winger, Katja; Sushama, Laxmi; Marshall, Shawn

    2016-04-01

    Glaciers are frozen fresh water reservoirs that respond to changes in temperature and snowfall. Concern is growing about the impact that changes in glaciers may have on water resources in regions such as western Canada that derive a lot of their summer streamflow from glacier melt. Given that RCM projections are an important tool and are increasingly being used in assessing projected changes to water resources, particularly due to its high resolution compared with GCMs, realistic representation of glaciers in RCMs is very important. Currently, glaciers are only represented in an extremely simplified way in the fifth generation Canadian Regional Climate Model (CRCM5). This simple approach of representing glaciers as static glacier masks is appropriate for short-term integrations, where the response of glacier to changing atmospheric conditions might still be small due to glacier response times and therefore the feedback of changing glacier extent on large-scale atmospheric flow conditions might be negligible. A new dynamic glacier scheme has been developed for use within CRCM5, based on volume-area relationships. Simulations have been performed with this glacier model and Land Surface Scheme CLASS for the 2000-2100 period over a domain covering western Canada. These simulations were driven by outputs from a CRCM5 transient climate change simulation driven by CanESM2 at the lateral boundaries, for RCPs 4.5 and 8.5. Preliminary results suggest significant decreases to glacier fractions in future climate. Though the glacier contribution to streamflows is found to dramatically decrease in future climate, the total streamflows did not show any dramatic decreases due to the increase in precipitation for these regions.

  10. Experience real-time climate change: Environmental education at Jamtal glacier.

    Science.gov (United States)

    Fischer, Andrea; Seiser, Bernd; Hartl, Lea; Bendler, Gebhard

    2016-04-01

    Kids hear about climate change in everyday news, but, unlike grown-ups, they find it much harder to imagine changes over decades, i.e. much longer than their own life span. So how to teach them the issues of climate change? Jamtalferner is an Alpine glacier with an ongoing mass balance monitoring programme started in 1988/89. Surveys of glacier length changes by the Austrian Alpine Club date back even longer, so that the glacier retreat after the Little Ice Age is well documented. As the glacier is easy to access, at just one hour's easy walk from the mountain hut, Jamtalferner was selected to compile materials on climate change for the use in schools and for preparing excursions for a hands-on confrontation with climate change and to give an impression of decadal changes. The materials will be available at www.umweltbildung-jamtal.info and include time series of photographs, maps, tables, background information and exercises.

  11. Recent evolution and mass balance of Cordón Martial glaciers, Cordillera Fueguina Oriental

    Science.gov (United States)

    Strelin, Jorge; Iturraspe, Rodolfo

    2007-10-01

    Past and present glacier changes have been studied at Cordón Martial, Cordillera Fueguina Oriental, Tierra del Fuego, providing novel data for the Holocene deglaciation history of southern South America and extrapolating as well its future behavior based on predicted climatic changes. Regional geomorphologic and stratigraphic correlations indicate that the last glacier advance deposited the ice-proximal ("internal") moraines of Cordón Martial, around 330 14C yr BP, during the Late Little Ice Age (LLIA). Since then glaciers have receded slowly, until 60 years ago, when major glacier retreat started. There is a good correspondence for the past 100 years between the surface area variation of four small cirque glaciers at Cordón Martial and the annual temperature and precipitation data of Ushuaia. Between 1984 and 1998, Martial Este Glacier lost 0.64 ± 0.02 × 10 6 m 3 of ice mass (0.59 ± 0.02 × 10 6 m 3 w.e.), corresponding to an average ice thinning of 7.0 ± 0.2 m (6.4 ± 0.2 m w.e), according to repeated topographic mapping. More detailed climatic data have been obtained since 1998 at the Martial Este Glacier, including air temperature, humidity and solar radiation. These records, together with the monthly mass balance measured since March 2000, document the annual response of the Martial Este Glacier to the climate variation. Mass balances during hydrological years were positive in 2000, negative in 2001 and near equilibrium in 2002. Finally, using these data and the regional temperature trend projections, modeled for different future scenarios by the Atmosphere-Ocean Model (GISS-NASA/GSFC), potential climatic-change effects on this mountain glacier were extrapolated. The analysis shows that only the Martial Este Glacier may survive this century.

  12. Mass balance evolution on two glaciers in the ecuadorian Andes (0°28'S) since the mid-20th century

    Science.gov (United States)

    Basantes, Ruben; Rabatel, Antoine; Alvarez, Danilo; Francou, Bernard; Galarraga, Remigio; Maisincho, Luis; Caceres, Bolivar

    2014-05-01

    The glacier mass balance evolution on two glaciers (Antisana Glacier 12 and Antisana Glacier 15α) in the tropical Andes is presented. To this end, photogrammetry technique was applied on aerial images taken at five dates: 1956, 1965, 1979, 1997 and 2009. For each date, digital elevation models (DEMs) were generated with an average vertical accuracy of ±2.2 m. The spatiotemporal volume variation of the glaciers is calculated through the elevations differences between DEMs and a density factor. The outcomes show that after 1970s the glaciers have experimented a strong recession even if a noticeable increase in mass was detected between 1965 and 1979. From 1979 to 1997, the ablation rates have dramatically increased and the average annual mass balance reached very negative values (-1.1 m w.e. yr-1 for Antisana Glacier 15α and -0.8 m w.e. yr-1 for Antisana Glacier 12). In the last study period, from 1997 to 2009, the glaciers average annual mass balances were less negative (-0.6 m w.e. yr-1 for Antisana Glacier 12 and -0.2 m w.e. yr-1 for Antisana Glacier 15α). The later matched with the period of conventional observations allowing compare the results given by both methodologies, i.e. geodetic and glaciological methods. However, some morphological constraints affecting the figures observed in the glaciological mass balance must be considered. Finally, we performed an analysis of the relationship between the glacier changes and the climate conditions over the study periods in order to understand how climate has impacted the glacier retreat in this region. For such an aim, local climate variables, i.e. temperature and precipitation, as well as regional indices, i.e. Pacific Decadal Oscillation (PDO) and Multivariate ENSO Index (MEI) have been used. The outcomes show a high correlation between the climate signals and the glacier behavior at both annual and decadal time scales.

  13. Past and future evolution of Himalayan glaciers: a regional climate model study

    Science.gov (United States)

    Kumar, Pankaj; Kotlarski, Sven; Moseley, Christopher; Sieck, Kevin; Frey, Holger; Stoffel, Markus; Jacob, Daniela

    2013-04-01

    Over 800 million people depend on glacier melt water runoff throughout the Hindu-Kush and Himalaya (HKH) region. The region, also called as "Water tower of Asia", is the location of several major rivers basins, like Ganges, Brahmaputra, and Indus etc. Glaciers in the HKH region are the primary source of water for the perennial rivers. Previous studies have assessed glacier areas and volumes in the HKH region by remote sensing techniques and slope-dependent thickness estimations. We here present a study in which, for the first time a glacier parameterization scheme is dynamically coupled to a regional climate model and applied over the South Asian Himalayan mountain range. The glacier scheme interactively simulates the mass balance as well as changes of the areal extent of glaciers on a sub-grid scale. Various observational data sets, in particular a regional glacier inventory, have been compiled and were used to initialize glacier area and volume in the year 1989. A simulation for the period 1989-2008 using the ECMWF ERA-Interim reanalysis as atmospheric boundary forcing was carried out. Preliminary results show a simulated decrease of glacier area of about 20% between 1989 and 2008. The spatial patterns of glacier area change show a remarkable decrease, but do show some regions of increase especially over the Karakoram (western Himalaya), a region for which available observations-based estimates also indicate a positive mass balance anomaly. The positive relation between altitude and mass balance is qualitatively reproduced by the model. The model is able to approximately represent the equilibrium line altitude (ELA) for selected sub-region when compared to observed values but simulated ELA's seem to have a systematic negative bias which, in turn, suggests an overestimation of the mean regional mass balance. Our results indicate that observed glacier changes can be approximately reproduced within a regional climate model based on simplified concepts of glacier-climate

  14. Linking glacier annual mass balance and glacier albedo retrieved from MODIS data

    OpenAIRE

    Dumont, M; Gardelle, J.; P. Sirguey; A. Guillot; Six, D.; Rabatel, A.; Y. Arnaud

    2012-01-01

    Albedo is one of the variables controlling the mass balance of temperate glaciers. Multispectral imagers, such as MODerate Imaging Spectroradiometer (MODIS) on board the TERRA and AQUA satellites, provide a means to monitor glacier surface albedo. In this study, different methods to retrieve broadband glacier surface albedo from MODIS data are compared. The effect of multiple reflections due to the rugged topography and of the anisotropic reflection of snow and ...

  15. Projections of glacier change in the Altai Mountains under twenty-first century climate scenarios

    Science.gov (United States)

    Zhang, Yong; Enomoto, Hiroyuki; Ohata, Tetsuo; Kitabata, Hideyuki; Kadota, Tsutomu; Hirabayashi, Yukiko

    2016-01-01

    We project glacier surface mass balances of the Altai Mountains over the period 2006-2100 for the representative concentration pathway (RCP) 4.5 and RCP8.5 scenarios using daily near-surface air temperature and precipitation from 12 global climate models in combination with a surface mass balance model. The results indicate that the Altai glaciers will undergo sustained mass loss throughout the 21st for both RCPs and reveal the future fate of glaciers of different sizes. By 2100, glacier area in the region will shrink by 26 ± 10 % for RCP4.5, while it will shrink by 60 ± 15 % for RCP8.5. According to our simulations, most disappearing glaciers are located in the western part of the Altai Mountains. For RCP4.5, all glaciers disappearing in the twenty-first century have a present-day size smaller than 5.0 km2, while for RCP8.5, an additional ~7 % of glaciers in the initial size class of 5.0-10.0 km2 also vanish. We project different trends in the total meltwater discharge of the region for the two RCPs, which does not peak before 2100, with important consequences for regional water availability, particular for the semi-arid and arid regions. This further highlights the potential implications of change in the Altai glaciers on regional hydrology and environment.

  16. Analysis of the mass balance time series of glaciers in the Italian Alps

    Science.gov (United States)

    Carturan, Luca; Baroni, Carlo; Brunetti, Michele; Carton, Alberto; Dalla Fontana, Giancarlo; Salvatore, Maria Cristina; Zanoner, Thomas; Zuecco, Giulia

    2016-03-01

    This work presents an analysis of the mass balance series of nine Italian glaciers, which were selected based on the length, continuity and reliability of observations. All glaciers experienced mass loss in the observation period, which is variable for the different glaciers and ranges between 10 and 47 years. The longest series display increasing mass loss rates, which were mainly due to increased ablation during longer and warmer ablation seasons. The mean annual mass balance (Ba) in the decade from 2004 to 2013 ranged from -1788 to -763 mm w.e. yr-1. Low-altitude glaciers with low range of elevation are more out of balance than the higher, larger and steeper glaciers, which maintain residual accumulation areas in their upper reaches. The response of glaciers is mainly controlled by the combination of October-May precipitations and June-September temperatures, but rapid geometric adjustments and atmospheric changes lead to modifications in their response to climatic variations. In particular, a decreasing correlation of Ba with the June-September temperatures and an increasing correlation with October-May precipitations are observed for some glaciers. In addition, the October-May temperatures tend to become significantly correlated with Ba, possibly indicating a decrease in the fraction of solid precipitation, and/or increased ablation, during the accumulation season. Because most of the monitored glaciers have no more accumulation area, their observations series are at risk due to their impending extinction, thus requiring a replacement soon.

  17. GIS analysis to apply theoretical Minimal Model on glacier flow line and assess glacier response in climate change scenarios

    OpenAIRE

    M. Moretti; Mattavelli, M; De Amicis, Mattia; Maggi, V

    2014-01-01

    The development of theoretical work about glacier dynamics has given rise to the construction of mathematical models to assess glacier response in climate change scenarios. Glacier are sentinels of climate condition and the Project of Interest NextData will favour new data production about the present and past climatic variability and future climate projections, as well as new assessments of the impact of climate change on environment. The aim of this specific research program is to develo...

  18. Little Ice Age climate reconstruction from ensemble reanalysis of Alpine glacier fluctuations

    Directory of Open Access Journals (Sweden)

    M. P. Lüthi

    2014-04-01

    Full Text Available Mountain glaciers sample a combination of climate fields – temperature, precipitation and radiation – by accumulation and melting of ice. Flow dynamics acts as a transfer function that maps volume changes to a length response of the glacier terminus. Long histories of terminus positions have been assembled for several glaciers in the Alps. Here I analyze terminus position histories from an ensemble of seven glaciers in the Alps with a macroscopic model of glacier dynamics to derive a history of glacier equilibrium line altitude (ELA for the time span 400–2010 C.E. The resulting climatic reconstruction depends only on records of glacier variations. The reconstructed ELA history is similar to recent reconstructions of Alpine summer temperature and Atlantic Multidecadal Oscillation (AMO index, but bears little resemblance to reconstructed precipitation variations. Most reconstructed low-ELA periods coincide with large explosive volcano eruptions, hinting at a direct effect of volcanic radiative cooling on mass balance. The glacier advances during the LIA, and the retreat after 1860, can thus be mainly attributed to temperature and volcanic radiative cooling.

  19. Influence of high-order mechanics on simulation of glacier response to climate change: insights from Haig Glacier, Canadian Rocky Mountains

    Directory of Open Access Journals (Sweden)

    S. Adhikari

    2013-09-01

    Full Text Available Evolution of glaciers in response to climate change has mostly been simulated using simplified dynamical models. Because these models do not account for the influence of high-order physics, corresponding results may exhibit some biases. For Haig Glacier in the Canadian Rocky Mountains, we test this hypothesis by comparing simulation results obtained from 3-D numerical models that deal with different assumptions concerning physics, ranging from simple shear deformation to comprehensive Stokes flow. In glacier retreat scenarios, we find a minimal role of high-order mechanics in glacier evolution, as geometric effects at our site (the presence of an overdeepened bed result in limited horizontal movement of ice (flow speed on the order of a few meters per year. Consequently, high-order and reduced models all predict that Haig Glacier ceases to exist by ca. 2080 under ongoing climate warming. The influence of high-order mechanics is evident, however, in glacier advance scenarios, where ice speeds are greater and ice dynamical effects become more important. Although similar studies on other glaciers are essential to generalize such findings, we advise that high-order mechanics are important and therefore should be considered while modeling the evolution of active glaciers. Reduced model predictions may be adequate for other glaciologic and topographic settings, particularly where flow speeds are low and where mass balance changes dominate over ice dynamics in determining glacier geometry.

  20. Gulkana Glacier, Alaska-Mass balance, meteorology, and water measurements, 1997-2001

    Science.gov (United States)

    March, Rod S.; O'Neel, Shad

    2011-01-01

    The measured winter snow, maximum winter snow, net, and annual balances for 1997-2001 in the Gulkana Glacier basin are determined at specific points and over the entire glacier area using the meteorological, hydrological, and glaciological data. We provide descriptions of glacier geometry to aid in estimation of conventional and reference surface mass balances and descriptions of ice motion to aid in the understanding of the glacier's response to its changing geometry. These data provide annual estimates for area altitude distribution, equilibrium line altitude, and accumulation area ratio during the study interval. New determinations of historical area altitude distributions are given for 1900 and annually from 1966 to 2001. As original weather instrumentation is nearing the end of its deployment lifespan, we provide new estimates of overlap comparisons and precipitation catch efficiency. During 1997-2001, Gulkana Glacier showed a continued and accelerated negative mass balance trend, especially below the equilibrium line altitude where thinning was pronounced. Ice motion also slowed, which combined with the negative mass balance, resulted in glacier retreat under a warming climate. Average annual runoff augmentation by glacier shrinkage for 1997-2001 was 25 percent compared to the previous average of 13 percent, in accordance with the measured glacier volume reductions.

  1. Strong ELA increase causes fast mass loss of glaciers in central Spitsbergen

    Science.gov (United States)

    Małecki, J.

    2015-11-01

    Svalbard is a heavily glacier covered archipelago in the Arctic. Its central regions, including Dickson Land (DL), are occupied by small alpine glaciers, which post-Little Ice Age (LIA) changes remain only sporadically investigated. This study presents a comprehensive analysis of glacier changes in DL based on inventories compiled from topographic maps and digital elevation models (DEMs) for LIA, 1960's, 1990 and 2009/11. The 37.9 ± 12.1 % glacier area decrease in DL (i.e. from 334.1 ± 38.4 km2 during LIA to 207.4 ± 4.6 km2 in 2009/11) has been primarily caused by accelerating termini retreat. The mean 1990-2009/11 geodetic mass balance of glaciers was -0.70 ± 0.06 m a-1 (-0.63 ± 0.05 m w.e. a-1), being one of the most negative from Svalbard regional means known from the literature. If the same figure was to be applied for other similar regions of central Spitsbergen, that would result in a considerable contribution to total Svalbard mass balance despite negligible proportion to total glacier area. Glacier changes in Dickson Land were linked to dramatic equilibrium line altitude (ELA) shift, which in the period 1990-2009/11 has been located ca. 500 m higher than required for steady-state. The mass balance of central Spitsbergen glaciers seems to be therefore more sensitive to climate change than previously thought.

  2. Glacier response to North Atlantic climate variability during the Holocene

    Directory of Open Access Journals (Sweden)

    N. L. Balascio

    2015-05-01

    Full Text Available Small glaciers and ice caps respond rapidly to climate variations and records of their past extent provide information on the natural envelope of past climate variability. Millennial-scale trends in Holocene glacier size are well documented and correspond with changes in Northern Hemisphere summer insolation. However, there is only sparse and fragmentary evidence for higher frequency variations in glacier size because in many Northern Hemisphere regions glacier advances of the past few hundred years were the most extensive and destroyed the geomorphic evidence of ice growth and retreat during the past several thousand years. Thus, most glacier records have been of limited use for investigating centennial scale climate forcing and feedback mechanisms. Here we report a continuous record of glacier activity for the last 9.5 ka from southeast Greenland, derived from high-resolution measurements on a proglacial lake sediment sequence. Physical and geochemical parameters show that the glaciers responded to previously documented Northern Hemisphere climatic excursions, including the "8.2 ka" cooling event, the Holocene Thermal Maximum, Neoglacial cooling, and 20th Century warming. In addition, the sediments indicate centennial-scale oscillations in glacier size during the late Holocene. Beginning at 4.1 ka, a series of abrupt glacier advances occurred, each lasting ~100 years and followed by a period of retreat, that were superimposed on a gradual trend toward larger glacier size. Thus, while declining summer insolation caused long-term cooling and glacier expansions during the late Holocene, climate system dynamics resulted in repeated episodes of glacier expansion and retreat on multi-decadal to centennial timescales. These episodes coincided with ice rafting events in the North Atlantic Ocean and periods of regional ice cap expansion, which confirms their regional significance and indicates that considerable glacier activity on these timescales is a

  3. Reconciling high-altitude precipitation in the upper Indus basin with glacier mass balances and runoff

    OpenAIRE

    Immerzeel, W. W.; N. Wanders; A. F. Lutz; J. M. Shea; M. F. P. Bierkens

    2015-01-01

    Mountain ranges in Asia are important water suppliers, especially if downstream climates are arid, water demands are high and glaciers are abundant. In such basins, the hydrological cycle depends heavily on high-altitude precipitation. Yet direct observations of high-altitude precipitation are lacking and satellite derived products are of insufficient resolution and quality to capture spatial variation and magnitude of mountain precipitation. Here we use glacier mass balances t...

  4. New climate change scenarios reveal uncertain future for Central Asian glaciers

    Directory of Open Access Journals (Sweden)

    A. F. Lutz

    2012-11-01

    Full Text Available Central Asian water resources largely depend on (glacier melt water generated in the Pamir and Tien Shan mountain ranges, located in the basins of the Amu and Syr Darya rivers, important life lines in Central Asia and the prominent water source of the Aral Sea. To estimate future water availability in the region, it is thus necessary to project the future glacier extent and volume in the Amu and Syr Darya river basins. The aim of this study is to quantify the impact of uncertainty in climate change projections on the future glacier extent in the Amu and Syr Darya river basins. The latest climate change projections provided by the fifth Coupled Model Intercomparison Project (CMIP5 generated for the upcoming fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC are used to model future glacier extent in the Central Asian region for the two large river basins. The outcomes are compared to model results obtained with the climate change projections used for the fourth IPCC assessment (CMIP3. We use a regionalized glacier mass balance model to estimate changes in glacier extent as a function of glacier size and projections of temperature and precipitation. The model is developed for implementation in (large scale hydrological models, when the spatial model resolution does not allow for modelling of individual glaciers and data scarcity is an issue. Both CMIP3 and CMIP5 model simulations point towards a strong decline in glacier extent in Central Asia. However, compared to the CMIP3 projections, the CMIP5 projections of future glacier extent in Central Asia provide a wider range of outcomes, mostly owing to greater variability in precipitation projections among the latest suite of climate models. These findings have great impact on projections of the timing and quantity of water availability in glacier melt dominated rivers in the region. Uncertainty about the size of the decline in glacier extent remains large, making

  5. Seasonal and annual mass balances of Mera and Pokalde glaciers (Nepal Himalaya since 2007

    Directory of Open Access Journals (Sweden)

    P. Wagnon

    2013-07-01

    Full Text Available In the Everest region, Nepal, ground-based monitoring programs were started on the debris-free Mera Glacier (27.7° N, 86.9° E; 5.1 km2, 6420 to 4940 m a.s.l. in 2007 and on the small Pokalde Glacier (27.9° N, 86.8° E; 0.1 km2, 5690 to 5430 m a.s.l., ∼ 25 km North of Mera Glacier in 2009. These glaciers lie on the southern flank of the central Himalaya under the direct influence of the Indian monsoon and receive more than 80% of their annual precipitation in summer (June to September. Despite a large inter-annual variability with glacier-wide mass balances ranging from −0.77± 0.40 m w.e. in 2011–2012 (Equilibrium-line altitude (ELA at ∼ 6055 m a.s.l. to + 0.46 ± 0.40 m w.e. in 2010–2011 (ELA at ∼ 5340 m a.s.l., Mera Glacier has been shrinking at a moderate mass balance rate of −0.10± 0.40 m w.e. yr−1 since 2007. Ice fluxes measured at two distinct transverse cross sections at ∼ 5350 m a.s.l. and ∼ 5520 m a.s.l. confirm that the mean state of this glacier over the last one or two decades corresponds to a limited mass loss, in agreement with remotely-sensed region-wide mass balances of the Everest area. Seasonal mass balance measurements show that ablation and accumulation are concomitant in summer which in turn is the key season controlling the annual glacier-wide mass balance. Unexpectedly, ablation occurs at all elevations in winter due to wind erosion and sublimation, with remobilized snow likely being sublimated in the atmosphere. Between 2009 and 2012, the small Pokalde Glacier lost mass more rapidly than Mera Glacier with respective mean glacier-wide mass balances of −0.72 and −0.26 ± 0.40 m w.e. yr−1. Low-elevation glaciers, such as Pokalde Glacier, have been usually preferred for in-situ observations in Nepal and more generally in the Himalayas, which may explain why compilations of ground-based mass balances are biased toward negative values compared with the regional mean under the present-day climate.

  6. Rapid response of Helheim Glacier in Greenland to climate variability over the past century

    DEFF Research Database (Denmark)

    Andresen, Camilla Snowman; Straneo, Fiammetta; Ribergaard, Mads Hvid;

    2012-01-01

    During the early 2000s the Greenland Ice Sheet experienced the largest ice-mass loss of the instrumental record(1), largely as a result of the acceleration, thinning and retreat of large outlet glaciers in West and southeast Greenland(2-5). The quasi-simultaneous change in the glaciers suggests...... a common climate forcing. Increasing air(6) and ocean(7,8) temperatures have been indicated as potential triggers. Here, we present a record of calving activity of Helheim Glacier, East Greenland, that extends back to about AD 1890, based on an analysis of sedimentary deposits from Sermilik Fjord, where...... Helheim Glacier terminates. Specifically, we use the annual deposition of sand grains as a proxy for iceberg discharge. Our record reveals large fluctuations in calving rates, but the present high rate was reproduced only in the 1930s. A comparison with climate indices indicates that high calving activity...

  7. Linking glacier annual mass balance and glacier albedo retrieved from MODIS data

    Directory of Open Access Journals (Sweden)

    M. Dumont

    2012-07-01

    Full Text Available Albedo is one of the variables controlling the mass balance of temperate glaciers. Multispectral imagers, such as MODerate Imaging Spectroradiometer (MODIS on board the TERRA and AQUA satellites, provide a means to monitor glacier surface albedo. In this study, different methods to retrieve broadband glacier surface albedo from MODIS data are compared. The effect of multiple reflections due to the rugged topography and of the anisotropic reflection of snow and ice are particularly investigated. The methods are tested on the Saint Sorlin Glacier (Grandes Rousses area, French Alps. The accuracy of the retrieved albedo is estimated using both field measurements, at two automatic weather stations located on the glacier, and albedo values derived from terrestrial photographs. For summers 2008 and 2009, the Root Mean Square Deviation (RMSD between field measurements and the broadband albedo retrieved from MODIS data at 250 m spatial resolution was found to be 0.052 or about 10% relative error. The RMSD estimated for the MOD10 daily albedo product is about three times higher. One decade (2000–2009 of MODIS data were then processed to create a time series of albedo maps of Saint Sorlin Glacier during the ablation season. The annual mass balance of Saint Sorlin Glacier was compared with the minimum albedo value (average over the whole glacier surface observed with MODIS during the ablation season. A strong linear correlation exists between the two variables. Furthermore, the date when the average albedo of the whole glacier reaches a minimum closely corresponds to the period when the snowline is located at its highest elevation, thus when the snowline is a good indicator of the glacier equilibrium line. This indicates that this strong correlation results from the fact that the minimal average albedo values of the glacier contains a considerable information regarding the relative share of areal surfaces between the ablation zone (i.e. ice with generally

  8. Towards remote monitoring of sub-seasonal glacier mass balance

    OpenAIRE

    Huss, Matthias; Sold, Leo; Hoelzle, Martin; Stokvis, Mazzal; Salzmann, Nadine; Farinotti Daniel; Zemp, Michael

    2013-01-01

    This study presents a method that allows continuous monitoring of mass balance for remote or inaccessible glaciers, based on repeated oblique photography. Hourly to daily pictures from two automatic cameras overlooking two large valley glaciers in the Swiss Alps are available for eight ablation seasons (2004–11) in total. We determine the fraction of snow-covered glacier surface from orthorectified and georeferenced images and combine this information with simple accumulation and melt modelli...

  9. Mass changes in Arctic ice caps and glaciers: implications of regionalizing elevation changes

    DEFF Research Database (Denmark)

    Nilsson, Johan; Sørensen, Louise Sandberg; Barletta, Valentina Roberta;

    2015-01-01

    The mass balance of glaciers and ice caps is sensitive to changing climate conditions. The mass changes derived n this study are determined from elevation changes derived measured by the Ice, Cloud, and land Elevation Satellite (ICESat) for the time period 2003–2009. Four methods, based...... of the regional mass balance of Arctic ice caps and glaciers to different regionalization schemes. The sensitivity analysis is based on studying the spread of mass changes and their associated errors, and the suitability of the different regionalization techniques is assessed through cross validation.The cross...

  10. Contributions of natural and anthropogenic radiative forcing to mass loss of Northern Hemisphere mountain glaciers and quantifying their uncertainties.

    Science.gov (United States)

    Hirabayashi, Yukiko; Nakano, Kazunari; Zhang, Yong; Watanabe, Satoshi; Tanoue, Masahiro; Kanae, Shinjiro

    2016-01-01

    Observational evidence indicates that a number of glaciers have lost mass in the past. Given that glaciers are highly impacted by the surrounding climate, human-influenced global warming may be partly responsible for mass loss. However, previous research studies have been limited to analyzing the past several decades, and it remains unclear whether past glacier mass losses are within the range of natural internal climate variability. Here, we apply an optimal fingerprinting technique to observed and reconstructed mass losses as well as multi-model general circulation model (GCM) simulations of mountain glacier mass to detect and attribute past glacier mass changes. An 8,800-year control simulation of glaciers enabled us to evaluate detectability. The results indicate that human-induced increases in greenhouse gases have contributed to the decreased area-weighted average masses of 85 analyzed glaciers. The effect was larger than the mass increase caused by natural forcing, although the contributions of natural and anthropogenic forcing to decreases in mass varied at the local scale. We also showed that the detection of anthropogenic or natural influences could not be fully attributed when natural internal climate variability was taken into account. PMID:27435236

  11. Contributions of natural and anthropogenic radiative forcing to mass loss of Northern Hemisphere mountain glaciers and quantifying their uncertainties

    Science.gov (United States)

    Hirabayashi, Yukiko; Nakano, Kazunari; Zhang, Yong; Watanabe, Satoshi; Tanoue, Masahiro; Kanae, Shinjiro

    2016-07-01

    Observational evidence indicates that a number of glaciers have lost mass in the past. Given that glaciers are highly impacted by the surrounding climate, human-influenced global warming may be partly responsible for mass loss. However, previous research studies have been limited to analyzing the past several decades, and it remains unclear whether past glacier mass losses are within the range of natural internal climate variability. Here, we apply an optimal fingerprinting technique to observed and reconstructed mass losses as well as multi-model general circulation model (GCM) simulations of mountain glacier mass to detect and attribute past glacier mass changes. An 8,800-year control simulation of glaciers enabled us to evaluate detectability. The results indicate that human-induced increases in greenhouse gases have contributed to the decreased area-weighted average masses of 85 analyzed glaciers. The effect was larger than the mass increase caused by natural forcing, although the contributions of natural and anthropogenic forcing to decreases in mass varied at the local scale. We also showed that the detection of anthropogenic or natural influences could not be fully attributed when natural internal climate variability was taken into account.

  12. Glacier modeling in support of field observations of mass balance at South Cascade Glacier, Washington, USA

    Science.gov (United States)

    Josberger, Edward G.; Bidlake, William R.

    2010-01-01

    The long-term USGS measurement and reporting of mass balance at South Cascade Glacier was assisted in balance years 2006 and 2007 by a new mass balance model. The model incorporates a temperature-index melt computation and accumulation is modeled from glacier air temperature and gaged precipitation at a remote site. Mass balance modeling was used with glaciological measurements to estimate dates and magnitudes of critical mass balance phenomena. In support of the modeling, a detailed analysis was made of the "glacier cooling effect" that reduces summer air temperature near the ice surface as compared to that predicted on the basis of a spatially uniform temperature lapse rate. The analysis was based on several years of data from measurements of near-surface air temperature on the glacier. The 2006 and 2007 winter balances of South Cascade Glacier, computed with this new, model-augmented methodology, were 2.61 and 3.41 mWE, respectively. The 2006 and 2007 summer balances were -4.20 and -3.63 mWE, respectively, and the 2006 and 2007 net balances were -1.59 and -0.22 mWE. PDF version of a presentation on the mass balance of South Cascade Glacier in Washington state. Presented at the American Geophysical Union Fall Meeting 2010.

  13. Climate- vs. Earthquake-induced Rock-Glacier Advances in the Tien Shan: Insights from Lichenometry

    Science.gov (United States)

    Rosenwinkel, Swenja; Landgraf, Angela; Korup, Oliver; Sorg, Annina

    2014-05-01

    Rock glaciers have been traditionally used as landform proxies of the distribution of sporadic alpine permafrost. In the northern Tien Shan mountains of Kyrgyzstan, most distinct lobes of >200 rock glaciers that we mapped from satellite imagery occur at two major elevation levels. However, a number of particularly low-lying lobes seem difficult to reconcile with palaeoclimatic fluctuations and commensurate changes of permafrost patterns: The minimum elevation of the majority of rock-glacier snouts lies between ~2500 up to ~3700 m a.s.l., but some 10% of rock-glaciers extend down to well below 3000 m a.s.l. We hypothesize that some of the rock glaciers in this area may have formed following strong earthquakes that could have triggered massive supraglacial rock-slope failures, which would have subsequently created sediment-rich rock glaciers from clear-ice glaciers. Our hypothesis is based on the observation that the tectonically active northern Tien Shan of Kyrgyzstan and Kazakhstan was affected by a series of major earthquakes in the late 19th and earliest 20th centuries, e.g. in 1885 (Ms 6.9), 1887 (Ms 7.3), 1889 (Ms 8.3), and 1911 (Ms 8.1). All of these earthquakes had triggered numerous landslides in the northern Tien Shan. It is also likely that similarly strong earthquakes had happened before, but their recurrence intervals are long and more palaeoseismological work is in progress. We test whether lichenometry of rock-glacier surfaces together with morphometric analysis are suitable methods to testing our hypothesis. We focus on assessing the possibility of earthquake-triggered rock-glacier advances, and use lichenometry to resolve age patterns of different rock-glacier lobes. We use a dataset of several thousand lichen diameter measurements encompassing seven different species calibrated by gravestones and dated mass-movement deposits. Data on four single and two merging rock glaciers in four selected valleys in Kyrgyzstan and Kazakhstan support the notion

  14. Density assumptions for converting geodetic glacier volume change to mass change

    Directory of Open Access Journals (Sweden)

    M. Huss

    2013-05-01

    Full Text Available The geodetic method is widely used for assessing changes in the mass balance of mountain glaciers. However, comparison of repeated digital elevation models only provides a glacier volume change that must be converted to a change in mass using a density assumption or model. This study investigates the use of a constant factor for the volume-to-mass conversion based on a firn compaction model applied to simplified glacier geometries with idealized climate forcing, and two glaciers with long-term mass balance series. It is shown that the "density" of geodetic volume change is not a constant factor and is systematically smaller than ice density in most cases. This is explained by the accretion/removal of low-density firn layers, and changes in the firn density profile with positive/negative mass balance. Assuming a value of 850 ± 60 kg m−3 to convert volume change to mass change is appropriate for a wide range of conditions. For short time intervals (≤3 yr, periods with limited volume change, and/or changing mass balance gradients, the conversion factor can however vary from 0–2000 kg m−3 and beyond, which requires caution when interpreting glacier mass changes based on geodetic surveys.

  15. Vulnerability of mountain glaciers in China to climate change

    Institute of Scientific and Technical Information of China (English)

    YANG Jian-Ping; DING Yong-Jian; LIU Shi-Yin; TAN Chun-Ping

    2015-01-01

    Mountain glaciers in China are an important water source for both China and adjoining countries, and therefore their adaptation to glacier change is crucial in relation to maintaining populations. This study aims to improve our understanding of glacial vulnerability to climate change to establish adaptation strategies. A glacial numerical model is developed using spatial principle component analysis (SPCA) supported by remote sensing (RS) and geographical information system (GIS) technologies. The model contains nine factorsdslope, aspect, hillshade, elevation a.s.l., air temperature, precipitation, glacial area change percentage, glacial type and glacial area, describing topography, climate, and glacier characteristics. The vulnerability of glaciers to climate change is evaluated during the period of 1961e2007 on a regional scale, and in the 2030s and 2050s based on projections of air temperature and precipitation changes under the IPCC RCP6.0 scenario and of glacier change in the 21st century. Glacial vulnerability is graded into five levels:potential, light, medial, heavy, and very heavy, using natural breaks classification (NBC). The spatial distribution of glacial vulnerability and its temporal changes in the 21st century for the RCP6.0 scenario are analyzed, and the factors influencing vulnerability are discussed. Results show that mountain glaciers in China are very vulnerable to climate change, and 41.2% of glacial areas fall into the levels of heavy and very heavy vulnerability in the period 1961e2007. This is mainly explained by topographical exposure and the high sensitivity of glaciers to climate change. Trends of glacial vulnerability are projected to decline in the 2030s and 2050s, but a declining trend is still high in some regions. In addition to topographical factors, variation in precipitation in the 2030s and 2050s is found to be crucial.

  16. The seasonal in-situ mass balance, temperature and precipitation of Yala Glacier, Langtang Valley, Nepal, from 2011 to 2015

    Science.gov (United States)

    Stumm, Dorothea; Fujita, Koji; Gurung, Tika; Joshi, Sharad; Litt, Maxime; Shea, Joseph; Sherpa, Mingma; Sinisalo, Anna; Wagnon, Patrick

    2016-04-01

    In-situ glacier mass balance measurements are still scarce in the Hindu Kush Himalayan (HKH) region and little is known about the seasonal balances. The glaciers in the Nepalese Himalaya have been considered summer accumulation glacier types because of the assumption that the majority of the accumulation occurs in the summer months during the monsoon. The glacier mass balance of Yala Glacier in the Langtang Valley of Nepal has been measured using the glaciological method since autumn 2011. Stakes were measured biannually in pre- and post-monsoon, usually in early May and in November, respectively. The measured mass balance gradient for the summer balance was larger than the winter balance, which is typical for glaciers with distinct ablation and accumulation seasons. On Yala Glacier, the summer balance was negative, and the winter balance was positive in all years with measurements. However, the annual net balance was negative for all four mass balance years from 2011 to 2015. The mass balances were further compared to temperature and precipitation data measured at nearby climate stations during the same time periods. In October 2013 and 2014, the Central Himalayas received large amounts of precipitation brought by the cyclones Phailin and Hudhud. These precipitation events contributed to the summer balance since the measurements were taken after the cyclones passed. In conclusion, on Yala Glacier accumulation processes dominated ablation processes during the winter, and ablation processes dominated during the summer, which could be explained by the low elevation range of Yala Glacier and precipitation from westerlies in the winter. Hence, this should be kept in mind when using the term 'summer accumulation glacier' for Yala Glacier. For future research in the HKH region, seasonal mass balances should be measured, and the processes impacting the mass balance and the role of winter precipitation should be investigated for other glaciers in the HKH region.

  17. Worldwide glacier monitoring as part of policy-related climate observation: development and strategy of the Global Terrestrial Network for Glaciers (GTN-G)

    Science.gov (United States)

    Haeberli, W.; Zemp, M.

    2011-12-01

    Internationally coordinated observation of long-term glacier fluctuations as a key indication of global climate changes has a long tradition, starting already in 1894. With the development of the Global Climate Observing System in support of the United Nations Framework Convention on Climate Change, glaciers and ice caps became an Essential Climate Variable within the Global Terrestrial Observing System. A corresponding Global Terrestrial Network for Glaciers (GTN-G) was indeed established as a pilot project to this program. The basic principles followed by GTN-G and similar networks are to be relevant, feasible, comprehensive and understandable to a wider scientific community and the public. Following recommendations by the International Council for Sciences, a contribution should be made to free and unrestricted international sharing of high-quality, long-term and standardized data and information products. A tiered strategy was adopted in order to bridge the gap between detailed process studies at selected field sites with global coverage through satellite remote sensing. Efforts were also made to ensure continuity of long-term measurement series by combining traditional approaches with modern, future-oriented technologies. Today, the GTN-G is jointly run by three operational bodies in glacier monitoring, which are the World Glacier Monitoring Service, the US National Snow and Ice Data Center, and the Global Land Ice Measurements from Space initiative. With an online service, GTN-G provides fast access to regularly updated information on glacier fluctuation and inventory data. Currently, this includes global information from 100,000 glaciers mainly based on aerial photographs and outlines from 95,000 glaciers mainly based on satellite images, length change series from 1,800 glaciers, mass balance series from 250 glaciers, information on special events (e.g., hazards, surges, calving instabilities) from 130 glaciers, as well as 13,000 photographs from some 500

  18. Glacier albedo decrease in the European Alps: potential causes and links with mass balances

    Science.gov (United States)

    Di Mauro, Biagio; Julitta, Tommaso; Colombo, Roberto

    2016-04-01

    Both mountain glaciers and polar ice sheets are losing mass all over the Earth. They are highly sensitive to climate variation, and the widespread reduction of glaciers has been ascribed to the atmospheric temperature increase. Beside this driver, also ice albedo plays a fundamental role in defining mass balance of glaciers. In fact, dark ice absorbs more energy causing faster glacier melting, and this can drive to more negative balances. Previous studies showed that the albedo of Himalayan glaciers and the Greenland Ice Sheet is decreasing with important rates. In this contribution, we tested the hypothesis that also glaciers in the European Alps are getting darker. We analyzed 16-year time series of MODIS (MODerate resolution Imaging Spectrometer) snow albedo from Terra (MOD13A1, 2000-2015) and Aqua (MYD13A1, 2002-2015) satellites. These data feature a spatial resolution of 500m and a daily temporal resolution. We evaluated the existence of a negative linear and nonlinear trend of the summer albedo values both at pixel and at glacier level. We also calculated the correlation between MODIS summer albedo and glacier mass balances (from the World Glaciological Monitoring Service, WGMS database), for all the glaciers with available mass balance during the considered period. In order to estimate the percentage of the summer albedo that can be explained by atmospheric temperature, we correlated MODIS albedo and monthly air temperature extracted from the ERA-Interim reanalysis dataset. Results show that decreasing trends exist with a strong spatial variability in the whole Alpine chain. In large glaciers, such as the Aletch (Swiss Alps), the trend varies significantly also within the glacier, showing that the trend is higher in the area across the accumulation and ablation zone. Over the 17 glaciers with mass balance available in the WGMS data set, 11 gave significant relationship with the MODIS summer albedo. Moreover, the comparison between ERA-Interim temperature

  19. Response sensitivities of a summer-accumulation type glacier to climate changes indicated with a glacier fluctuation model

    OpenAIRE

    NAITO, Nozomu; AGETA, Yutaka; Nakawo, Masayoshi; Edwin,D. Waddington; Charles,F. Raymond; Howard,Conway

    2001-01-01

    Sensitivities of a summer-accumulation type glacier in response to changes in air temperature and precipitation are investigated using a glacier fluctuation model. The model couples glacier dynamics to empirical mass balance equations obtained for a typical summer-accumulation type glacier in the eastern Nepal Himalayas. The geometry and seasonal variations in air temperature and precipitation are simplified in order to examine the principal characteristics of the sensitivities. The magnitude...

  20. Brief Communication: Global glacier mass loss reconstructions during the 20th century are consistent

    Directory of Open Access Journals (Sweden)

    B. Marzeion

    2015-07-01

    Full Text Available Estimates of the contribution of glaciers to sea-level rise during the 20th century that were published in recent years are strongly divergent. Advances in data availability have allowed revisions of some of these published estimates. Here we show that outside of Antarctica, the global estimates of glacier mass loss obtained from glacier-length-based reconstructions and from a glacier model driven by gridded climate observations are now consistent with each other, and also with an estimate for the years 2003–2009 that is mostly based on remotely sensed data. This consistency is found throughout the entire common periods of the respective data sets. Inconsistencies of reconstructions and observations persist in estimates on regional scales.

  1. Brief Communication: Global reconstructions of glacier mass change during the 20th century are consistent

    Science.gov (United States)

    Marzeion, B.; Leclercq, P. W.; Cogley, J. G.; Jarosch, A. H.

    2015-12-01

    Recent estimates of the contribution of glaciers to sea-level rise during the 20th century are strongly divergent. Advances in data availability have allowed revisions of some of these published estimates. Here we show that outside of Antarctica, the global estimates of glacier mass change obtained from glacier-length-based reconstructions and from a glacier model driven by gridded climate observations are now consistent with each other, and also with an estimate for the years 2003-2009 that is mostly based on remotely sensed data. This consistency is found throughout the entire common periods of the respective data sets. Inconsistencies of reconstructions and observations persist in estimates on regional scales.

  2. Development of GIS methods to assess glaciers response to climatic fluctuations: a Minimal Model approach

    OpenAIRE

    Strigaro, D; M. Moretti; Mattavelli, M.; De Amicis, M; V. Maggi; Provenzale, A.

    2015-01-01

    Theoretical work on glacier dynamics led to the construction of mathematical models for estimating glacier response to different climate change scenarios [2]. The aim of this work is to include a simple version of such models (the so-called Minimal Glacier Models [6]) within a GIS framework, to better understand, evaluate and reproduce the glacier response to climate fluctuations. Then, in this work three sections have been included: (I) the formulation of the Minimal Glacier Models, evalu...

  3. Surface Mass Balance of the Columbia Glacier, Alaska, 1978 and 2010 Balance Years

    Science.gov (United States)

    O'Neel, Shad

    2012-01-01

    Although Columbia Glacier is one of the largest sources of glacier mass loss in Alaska, surface mass balance measurements are sparse, with only a single data set available from 1978. The dearth of surface mass-balance data prohibits partitioning of the total mass losses between dynamics and surface forcing; however, the accurate inclusion of calving glaciers into predictive models requires both dynamic and climatic forcing of total mass balance. During 2010, the U.S. Geological Survey collected surface balance data at several locations distributed over the surface of Columbia Glacier to estimate the glacier-wide annual balance for balance year 2010 using the 2007 area-altitude distribution. This report also summarizes data collected in 1978, calculates the 1978 annual surface balance, and uses these observations to constrain the 2010 values, particularly the shape of the balance profile. Both years exhibit balances indicative of near-equilibrium surface mass-balance conditions, and demonstrate the importance of dynamic processes during the rapid retreat.

  4. Earth's Climate History from Glaciers and Ice Cores

    Science.gov (United States)

    Thompson, Lonnie

    2013-03-01

    Glaciers serve both as recorders and early indicators of climate change. Over the past 35 years our research team has recovered climatic and environmental histories from ice cores drilled in both Polar Regions and from low to mid-latitude, high-elevation ice fields. Those ice core -derived proxy records extending back 25,000 years have made it possible to compare glacial stage conditions in the Tropics with those in the Polar Regions. High-resolution records of δ18O (in part a temperature proxy) demonstrate that the current warming at high elevations in the mid- to lower latitudes is unprecedented for the last two millennia, although at many sites the early Holocene was warmer than today. Remarkable similarities between changes in the highland and coastal cultures of Peru and regional climate variability, especially precipitation, imply a strong connection between prehistoric human activities and regional climate. Ice cores retrieved from shrinking glaciers around the world confirm their continuous existence for periods ranging from hundreds to thousands of years, suggesting that current climatological conditions in those regions today are different from those under which these ice fields originated and have been sustained. The ongoing widespread melting of high-elevation glaciers and ice caps, particularly in low to middle latitudes, provides strong evidence that a large-scale, pervasive and, in some cases, rapid change in Earth's climate system is underway. Observations of glacier shrinkage during the 20th and 21st century girdle the globe from the South American Andes, the Himalayas, Kilimanjaro (Tanzania, Africa) and glaciers near Puncak Jaya, Indonesia (New Guinea). The history and fate of these ice caps, told through the adventure, beauty and the scientific evidence from some of world's most remote mountain tops, provide a global perspective for contemporary climate. NSF Paleoclimate Program

  5. Herfried Hoinkes: pioneer of degree-day methods to calculate glacier mass-balance from air temperature

    OpenAIRE

    R. J. Braithwaite

    2015-01-01

    Herfried Hoinkes (1916 to 1975) was a glacier researcher and university teacher who made great contributions to the early development of modern glaciology but I concentrate on his work on the mass balance of an Austrian glacier Hintereisferner. In a series of paper from 1962 to 1975, he showed that the mass balance is strongly correlated with positive degree-day (PDD) totals extrapolated from a nearby climate station. He achieved further improvements in correlations by accounting for fresh sn...

  6. Region-wide glacier mass balances over the Pamir-Karakoram-Himalaya during 1999–2011

    Directory of Open Access Journals (Sweden)

    J. Gardelle

    2013-03-01

    Full Text Available The recent evolution of Pamir-Karakoram-Himalaya (PKH glaciers, widely acknowledged as valuable high-altitude as well as mid-latitude climatic indicators, remains poorly known. To overcome the lack of region-wide mass balance data, we compared the 2000 Shuttle Radar Topography Mission (SRTM digital elevation model (DEM to recent (2008–2011 DEMs derived from SPOT5 stereo-imagery for 8 sites spread from Pamir to eastern Himalaya. The region-wide glacier mass balances were contrasted during the last decade, with moderate mass losses in eastern and central Himalaya (−0.21 ± 0.10 m yr−1 w.e. to −0.29 ± 0.09 m yr−1 w.e. and larger losses in western Himalaya (−0.41 ± 0.11 m yr−1 w.e.. Recently reported slight mass gain of glaciers in central Karakoram is confirmed for a larger area (+0.10 ± 0.19 m yr−1 w.e. and, new, also observed for glaciers in western Pamir (+0.14 ± 0.10 m yr−1 w.e.. We propose that the "Karakoram anomaly" should be renamed the "Pamir-Karakoram anomaly", at least for the last decade. The overall mass balance of PKH glaciers is estimated at −0.12 ± 0.06 m yr−1 w.e. In contrast to Indus, the relative glacier imbalance contribution to Brahmaputra and Ganges discharges is higher than previously modeled glacier seasonal contribution.

  7. Reconstructing glacier-based climates of LGM Europe and Russia – Part 2: A dataset of LGM climates derived from degree-day modelling of palaeo glaciers

    Directory of Open Access Journals (Sweden)

    A. J. Payne

    2007-10-01

    Full Text Available The study of European and Russian Quaternary glacial-geological evidence during the last 15 years has generated sufficient to data to use former glacial extent as a proxy for Last Glacial Maximum (LGM climate at a continental scale. Utilisation of such data is relevant for two reasons. First, continental to global scale proxy reconstructions of past climate are an important tool in the assessment of retrospective general circulation model (GCM simulations. Second, the development of a multi-proxy approach will result in a more robust proxy based climate signal. A new and independent dataset of 36 LGM climate estimates derived from European and Russian mountain regions is presented in this paper. A simple glacier-climate model was used to establish the optimum LGM climate conditions for each region from a suite of over 4000 model climates using the principle of zero cumulative mass balance. Clear regional trends are present in the reconstructed LGM climates; temperature anomalies north of the Alps are 2°C and 5°C larger than those in the western and eastern Mediterranean, respectively. In Russia the model results suggest that both the Arctic Urals and Puterana Plateau were probably glaciated by small mountain glaciers during the LGM.

  8. 祁连山七一冰川物质平衡及其对气候变化的敏感性研究%Study of Mass Balance and Sensibility to Climate Change of Qiyi Glacier in Qilian Mountains

    Institute of Scientific and Technical Information of China (English)

    王盛; 蒲健辰; 王宁练

    2011-01-01

    依据2010年6月30日-9月5日考察期间获得的七一冰川物质平衡和气温降水等气象资料,运用度日物质平衡模型模拟了七一冰川的物质平衡变化状况.结果表明:七一冰川考察期间物质平衡为-856.2mm w.e..受气温、降水等气候因素的强烈影响,物质平衡过程明显分为"微弱积累-强烈消融-微弱消融"3个阶段.度日物质平衡模型模拟的冰川物质平衡与实测值的变化趋势基本一致,整体反映了冰川物质平衡随海拔上升而增大的空间分布特征.物质平衡的气候敏感性实验表明,物质平衡对气温升降的变化非常敏感,气温是影响冰川物质平衡的主导因素,当气温持续升高时,降水量的少量增加对物质平衡的影响将变得很小.%Based on glacier mass balance,air temperature and precipitation of the Qiyi Glacier from Jun.30 to Sept.5,2010,a degree-day mass balance model was established to imitate the change of mass balance during this period.Observation indicates that the value of mass balance was-856.2 mm w.e.,which is subjected to strong impact of air temperature and precipitation.The mass balance process can be divided into three stages,i.e.,exiguous accumulation,intensive ablation and exiguous ablation.The variation trend of mass balance simulated with the degree-day mass balance model is similar to the observed one.The simulation wholly reflects the spatial distribution characteristics of glacier mass balance which increases with the increase of altitude.The experiment on climate sensitivity of mass balance shows that mass balance is very sensitive to the change of air temperature;air temperature is the key factor which influences mass balance;when air temperature rises continuously,a little increase in precipitation will have a negligible effect on mass balance.

  9. Deducing high-altitude precipitation from glacier mass balance measurements

    Science.gov (United States)

    Giesen, Rianne H.; Immerzeel, Walter W.; Wanders, Niko

    2016-04-01

    The spatial distribution of precipitation in mountainous terrain is generally not well known due to underrepresentation of gauge observations at higher elevations. Precipitation tends to increase with elevation, but since observations are mainly performed in the valleys, the vertical precipitation gradient cannot be deduced from these measurements. Furthermore, the spatial resolution of gridded meteorological data is often too coarse to resolve individual mountain chains. Still, a reliable estimate of high-elevation precipitation is required for many hydrological applications. We present a method to determine the vertical precipitation gradient in mountainous terrain, making use of glacier mass balance observations. These measurements have the advantage that they provide a basin-wide precipitation estimate at high elevations. The precipitation gradient is adjusted until the solid precipitation over the glacier area combined with the calculated melt gives the measured annual glacier mass balance. Results for the glacierized regions in Central Europe and Scandinavia reveal spatially coherent patterns, with predominantly positive precipitation gradients ranging from -4 to +28 % (100 m)‑1. In some regions, precipitation amounts at high elevations are up to four times as large as in the valleys. A comparison of the modelled winter precipitation with observed snow accumulation on glaciers shows a good agreement. Precipitation measured at the few high-altitude meteorological stations is generally lower than our estimate, which may result from precipitation undercatch. Our findings will improve the precipitation forcing for glacier modelling and hydrological studies in mountainous terrain.

  10. Trends and variability in the global dataset of glacier mass balance

    Science.gov (United States)

    Medwedeff, William G.; Roe, Gerard H.

    2016-06-01

    Glacier mass balance (i.e., accumulation and ablation) is the most direct connection between climate and glaciers. We perform a comprehensive evaluation of the available global network of mass-balance measurements. Each mass-balance time series is decomposed into a trend and the variability about that trend. Observed variability ranges by an order of magnitude, depending on climate setting (i.e., maritime vs continental). For the great majority of glaciers, variability is well characterized by normally distributed, random fluctuations that are uncorrelated between seasons, or in subsequent years. The magnitude of variability for both summer and winter is well correlated with mean wintertime balance, which reflects the climatic setting. Collectively, summertime variability exceeds wintertime variability, except for maritime glaciers. Trends in annual mass balance are generally negative, driven primarily by summertime changes. Approximately 25 % of annual-mean records show statistically significant negative trends when judged in isolation. In aggregate, the global trend is negative and significant. We further evaluate the magnitude of trends relative to the variability. We find that, on average, trends are approximately -0.2 standard deviations per decade, although there is a broad spread among individual glaciers. Finally, for two long records we also compare mass-balance trends and variability with nearby meteorological stations. We find significant differences among stations meaning caution is warranted in interpreting any point measurement (such as mass balance) as representative of region-wide behavior. By placing observed trends in the context of natural variability, the results are useful for interpreting past glacial history, and for placing constraints on future predictability.

  11. Holocene glacier variability: three case studies using an intermediate-complexity climate model

    NARCIS (Netherlands)

    Weber, S.L.; Oerlemans, J.

    2003-01-01

    Synthetic glacier length records are generated for the Holocene epoch using a process-based glacier model coupled to the intermediate-complexity climate model ECBilt. The glacier model consists of a massbalance component and an ice-flow component. The climate model is forced by the insolation change

  12. As climate changes, so do glaciers

    OpenAIRE

    Lowell, Thomas V.

    2000-01-01

    Understanding abrupt climate changes requires detailed spatial/temporal records of such changes, and to make these records, we need rapidly responding, geographically widespread climate trackers. Glacial systems are such trackers, and recent additions to the stratigraphic record show overall synchronous response of glacial systems to climate change reflecting global atmosphere conditions.

  13. Mass balance and near-surface ice temperature structure of Baishui Glacier No.1 in Mt.Yulong

    Institute of Scientific and Technical Information of China (English)

    DU Jiankuo; HE Yuanqing; LI Shuang; WANG Shijin; NIU Hewen; XIN Huijuan; PU Tao

    2013-01-01

    The accumulation and ablation of a glacier directly reflect its mass income and wastage,and ice temperature indicates glacier's climatic and dynamic conditions.Glaciological studies at Baishui Glacier No.1 in Mt.Yulong are important for estimating recent changes of the cryosphere in Hengduan Mountains.Increased glacier ablation and higher ice temperatures can cause the incidents of icefall.Therefore,it is important to conduct the study of glacier mass balance and ice temperature,but there are few studies in relation to glacier's mass balance and active-layer temperature in China's monsoonal temperate glacier region.Based on the field observations of mass balance and glacier temperature at Baishui Glacier No.1,its accumulation,ablation,net balance and near-surface ice temperature structure were analyzed and studied in this paper.Results showed that the accumulation period was ranged from October to the following mid-May,and the ablation period occurred from mid-May to October,suggesting that the ablation period of temperate glacier began about 15 days earlier than that of continental glaciers,while the accumulation period began about 15 days later.The glacier ablation rate was 6.47 cm d-1 at an elevation of 4600 m between June 23 and August 30,and it was 7.4 cm d-1 at 4800 m between June 26 and July 11 in 1982,moreover,they respectively increased to 9.2 cm d-1 and 10.8 cm d-1 in the corresponding period and altitude in 2009,indicating that glacier ablation has greatly intensified in the past years.The temperature of the main glacier body was close to melting point in summer,and it dropped from the glacier surface and reached a minimum value at a depth of 4-6 m in the ablation zone.The temperature then rose to around melting point with the depth increment.In winter,the ice temperature rose gradually with the increasing depth,and close to melting point at the depth of 10 m.Compared with the data from 1982,the glacier temperature has risen in the ablation zone in

  14. Frequency, triggering factors and possible consequences of mass movements on outlet glaciers in Iceland.

    Science.gov (United States)

    Saemundsson, Thorsteinn; Margeirsson, Guðbjörn

    2016-04-01

    During the last 15 years several mass movements of various size and origin, e.g. rock avalanches, rock slides and debris slides have been observed to have fall on outlet glaciers in Iceland. This should not come as a surprise in this type of glacial environment, but in a way it does. When looking at the history only few mass movements are recorded to have fall on outlet glaciers in Iceland, during the decades before the year 2000 or since 1960. This "lack of mass movements" can be explained by the fact that fewer observations and monitoring were done in the past, but is it so or are we seeing increasing activity? Looking at the distribution of the known mass movements, two activity periods cam be identified. The former one around 1970 and the second one starting around 2000 and is still ongoing. Both of these periods are characterized by warmer climate leading to retreating phases of glaciers. Two larger mass movements are known from these two retreating periods. The former one occurred in January 1967. Then a large rockslide fell on the snout and into the glacial lake of the Steinholtsjökull outlet glacier in the northern side of the Eyjafjallajökull ice cap. The rockslide broke up the snout of the glacier and caused large floodwave bursting down the Steinholtsdalur valley transporting large volume of sediments down its path. The later one occurred in 2007, when a large rockavalanche fell on the Morsárjökull outlet glacier, in the southern side of the Vatnajökull ice cap. The avalanche debris covered around 1/5 of the glacier surface. Today the retreat and thinning of glaciers in Iceland are extremely rapid. The consequences of such a rapid retreat are e.g. unstable valley slopes surrounding the outlet glaciers, both in loose sediments and bedrock, thawing of mountain permafrost and not least formation of glacial lakes in front of the rapid retreating ice margins. Such conditions can become extremely hazardous, as seen by the above mentioned examples, both

  15. Simulation and reconstruction of parameters of streamflow and glacier mass balance in the Northern Caucasus

    Directory of Open Access Journals (Sweden)

    V. G. Konovalov

    2014-01-01

    Full Text Available The work was aimed at numerical modeling of spatial-temporal variability of the river Terek seasonal (April to September streamflow characteristics and long-term fluctuations of components of annual glacier mass balances in this basin and on the adjacent territories. Mass balance of glaciers Djankuat and Garabashi was calculated. Simulation was performed by means of stochastic modeling and discrete data presenting fields of main meteorological parameters (precipitation, air temperature and humidity having effect on the streamflow. Realization of this approach is complicated by the fact that spatial representativeness of hydrological and meteorological sites are not corresponding one to another. Data on the runoff is clearly related to the total drainage area closed by a gauging station. And for this data we study a relationship with meteorological parameters which are measured at a non-regular observational network whose spatial representativeness is unknown. These stations are generally located beyond the area under investigation (Fig. 2. Similar problem exists when we analyze a relationship between components of the mass balance of individual glaciers (Djankuat and Garabashi and the above climate characteristics measured at some stations located on the whole Caucasus territory. The same takes place when long-term indices of width and density of tree annual rings obtained in upper reaches of the river Kuban’ are used for analysis of variations of the runoff and the glacier mass balance in the river Terek basin located at a distance of 100-150 km from the Kuban’ dendrologic sites.To solve the problem we used a wide number of factors which directly (various information about the climate or indirectly (indices of the climate dryness, wood ring characteristics characterize conditions of formation of annual and seasonal river runoff and components of glacier mass balance in the North Caucasus. Use of all obtained information made possible the

  16. A model study of the energy and mass balance of Chhota Shigri glacier in the Western Himalaya, India

    Directory of Open Access Journals (Sweden)

    F. Pithan

    2011-01-01

    Full Text Available The impact of climate change on Himalaya mountain glaciers is increasingly subject of public and scientific debate. However, observational data are sparse and important knowledge gaps remain in the understanding of what drives changes in these glaciers' mass balances. The present study investigates the glacier regime on Chhota Shigri, a benchmark glacier for the observation of climate change in the monsoon-arid transition zone of Western Himalaya. Results of an energy-balance model driven by reanalysis data and the observed mass balances from three years on 50 m altitude intervals across the glacier display a correlation coefficient of 0.974. Contrary to prior assumptions, monsoon precipitation accounts for a quarter to a third of total accumulation. It has an additional importance because it lowers the surface albedo during the ablation season. Results confirm radiation as the main energy source for melt on Himalaya glaciers. Latent heat flux acts as an important energy sink in the pre-monsoon season. Mass balance is most sensitive to changes in atmospheric humidity, changing by 900 mm w.e. per 10% change in humidity. Temperature sensitivity is 220 mm w.e.K−1. Model results using 21st century anomalies from a regional climate model based on the SRES A2 scenario suggest that a monsoon increase might offset the effect of warming.

  17. Fifty-Year Record of Glacier Change Reveals Shifting Climate in the Pacific Northwest and Alaska, USA

    Science.gov (United States)

    U.S. Geological Survey

    2009-01-01

    Fifty years of U.S. Geological Survey (USGS) research on glacier change shows recent dramatic shrinkage of glaciers in three climatic regions of the United States. These long periods of record provide clues to the climate shifts that may be driving glacier change. The USGS Benchmark Glacier Program began in 1957 as a result of research efforts during the International Geophysical Year (Meier and others, 1971). Annual data collection occurs at three glaciers that represent three climatic regions in the United States: South Cascade Glacier in the Cascade Mountains of Washington State; Wolverine Glacier on the Kenai Peninsula near Anchorage, Alaska; and Gulkana Glacier in the interior of Alaska (fig. 1).

  18. Glacier annual balance measurement, prediction, forecasting and climate correlations, North Cascades, Washington 1984–2006

    Directory of Open Access Journals (Sweden)

    M. S. Pelto

    2007-06-01

    Full Text Available North Cascade glacier annual balance measured on 10 glaciers from 1984–2006 yielded mean annual balance (ba of –0.54 m/a, and –12.38 m cumulatively. This is a significant loss for glaciers that average 30–60 m in thickness, representing 20–40% of their entire volume. Two observed glaciers, Lewis Glacier and Spider Glacier, no longer exist. The ba of North Cascade glaciers is reliably calculated based on 1 April snowpack water equivalent and ablation season temperature. 1 May forecasting of ba using the Pacific Decadal Oscillation and the Multivariate El Nino Southern Oscillation circulation indices correctly determined the sign of mass balance in 42 of 47 years. Glacier annual balance forecasting is an important step for summer water resource management in glacier runoff dominated stream systems. The forecast for North Cascade glaciers in 2007 is for a negative annual balance.

  19. Reconstructing the mass balance of Brewster Glacier, New Zealand, using MODIS-derived glacier-wide albedo

    OpenAIRE

    Sirguey, Pascal; Still, Holly; Cullen, Nicolas J.; Dumont, Marie; Arnaud, Yves; Conway, Jonathan P.

    2016-01-01

    In New Zealand, direct measurements of mass balance are sparse due to the inaccessibility of glaciers in the Southern Alps and the logistical difficulties associated with maintaining a mass balance record. In order to explore the benefit of remotely sensed imaging to monitor mass balance in the Southern Alps, this research assesses the relationship between measurements of glacier surface albedo derived from MODerate resolution Imaging Spectroradiometer (MODIS) and mass balance observations us...

  20. A comparison of different methods of evaluating glacier response characteristics: application to glacier AX010, Nepal Himalaya

    OpenAIRE

    Adhikari, S; Marshall, S. J.; Huybrechts, P.

    2009-01-01

    Himalayan glaciers are considered to be amongst the most sensitive glaciers to climate change. However, the response behaviour of these glaciers is not well understood. Here we use several approaches to estimate characteristic timescales of glacier AX010, a small valley glacier in the Nepal Himalaya, as a measure of glacier sensitivity. Assuming that temperature solely defines the mass budget, glacier AX010 waits for about 8 yr (r...

  1. Spatial patterns of North Atlantic Oscillation influence on mass balance variability of European glaciers

    OpenAIRE

    Marzeion, B.; A. Nesje

    2012-01-01

    We present and validate a set of minimal models of glacier mass balance variability. The most skillful model is then applied to reconstruct 7735 individual time series of mass balance variability for all glaciers in the European Alps and Scandinavia. Subsequently, we investigate the influence of atmospheric variability associated with the North Atlantic Oscillation (NAO) on the glaciers' mass balances.

    We find a spatial coherence in the glaciers' sensitivity to NA...

  2. Hydrological response to climate change in a glacierized catchment in the Himalayas

    OpenAIRE

    Immerzeel, Walter W.; van Beek, L. P. H.; Konz, M.; Shrestha, A. B.; M. F. P. Bierkens

    2011-01-01

    The analysis of climate change impact on the hydrology of high altitude glacierized catchments in the Himalayas is complex due to the high variability in climate, lack of data, large uncertainties in climate change projection and uncertainty about the response of glaciers. Therefore a high resolution combined cryospheric hydrological model was developed and calibrated that explicitly simulates glacier evolution and all major hydrological processes. The model was used to assess the future deve...

  3. Modeling energy and mass balance of Shallap Glacier, Peru

    Directory of Open Access Journals (Sweden)

    W. Gurgiser

    2013-11-01

    Full Text Available We calculated the distributed surface mass and energy balance of Shallap Glacier, Cordillera Blanca, Peru (9° S, 77° W, 4700–5700 m a.s.l., ~ 7 km2, on hourly time steps for two years (September 2006–August 2008 using a process-based model and meteorological measurements as input. Model parameter combinations were optimized against 21 temporal readings of 20 stakes in the ablation zone of the glacier. Uncertainty caused by model input parameters and parameterization schemes was estimated using a leave-one out cross-validation scheme, which yields values of root mean square deviation (RMSD of surface height change < 1 m (< 10% of the measured amplitude for all stakes. With the best parameter combination (smallest RMSD applied, the modeled annual surface mass balance of the glacier was −0.32 ± 0.4 m w.e. (water equivalent for September 2006–August 2007 and 0.51 ± 0.56 m w.e. for September 2007–August 2008. While the mass balance above 5000 m was similar in both years (Δ 0.33 ± 0.68 m w.e. due to similar annual sums of solid precipitation, a difference of 1.97 ± 0.68 m w.e. was calculated for the lower parts of the glacier. This difference is associated with more frequent occurrence of higher snow line altitudes during the first year, which was mainly caused by a higher fraction of liquid precipitation due to higher mean air temperatures. As the net shortwave budget was found to be the main source for ablation throughout the year at Shallap Glacier, lower surface albedo especially caused by lower solid precipitation amounts explains most of the difference in modeled ablation and mass balance between the two years.

  4. Modeling energy and mass balance of Shallap Glacier, Peru

    Directory of Open Access Journals (Sweden)

    W. Gurgiser

    2013-08-01

    Full Text Available We calculated the distributed surface mass and energy balance of Shallap Glacier, Cordillera Blanca, Peru (9° S, 77° W, 4700–5700 m a.s.l., ∼ 7 km2 on hourly time steps for two years (September 2006–August 2008 using a process-based model and meteorological measurements as input. Model parameter combinations were optimized against 21 temporal readings of 20 stakes in the ablation zone of the glacier. Uncertainty caused by model input parameters and parameterization schemes was estimated using a leave-one-out cross-validation scheme and yields values of root mean square deviation (RMSD of surface height change < 1m (< 10% of the measured amplitude for all stakes. With the best parameter combination (smallest RMSD applied, the modeled annual surface mass balance of the glacier was −0.32 ± 0.4 m w.e. for September 2006–August 2007 and 0.51 ± 0.56 m w.e. for September 2007–August 2008. While the mass balance above 5000 m was similar in both years (Δ 0.35 ± 0.68 m w.e. due to similar annual sums of solid precipitation, a difference of ∼ 2 ± 0.68 m w.e. was calculated for the lower parts of the glacier. This difference is associated with more frequent occurrence of higher snow line altitudes during the first year, which was mainly caused by a higher fraction of liquid precipitation due to higher mean air temperatures. As the net shortwave budget was found to be the main source for ablation throughout the year at Shallap Glacier, lower surface albedo caused by higher snow line altitudes explains most of the difference in modeled ablation and mass balance between the two years.

  5. Review article of the current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change

    Directory of Open Access Journals (Sweden)

    A. Rabatel

    2012-07-01

    Full Text Available The aim of this paper is to provide the community with a comprehensive overview of the studies of glaciers in the tropical Andes conducted in recent decades leading to the current status of the glaciers in the context of climate change. In terms of changes in surface area and length, we show that the glacier retreat in the tropical Andes over the last three decades is unprecedented since the maximum extension of the LIA (mid 17th–early 18th century. In terms of changes in mass balance, although there have been some sporadic gains on several glaciers, we show that the trend has been quite negative over the past 50 yr, with a mean mass balance deficit for glaciers in the tropical Andes that is slightly more negative than the computed global average. A break point in the trend appeared in the late 1970s with mean annual mass balance per year decreasing from −0.2 m w.e. in the period 1964–1975 to −0.76 m w.e. in the period 1976–2010. In addition, even if glaciers are currently retreating everywhere in the tropical Andes, it should be noted that as a percentage, this is much more pronounced on small glaciers at low altitudes that do not have a permanent accumulation zone, and which could disappear in the coming years/decades. Monthly mass balance measurements performed in Bolivia, Ecuador and Colombia showed that variability of the surface temperature of the Pacific Ocean is the main factor governing variability of the mass balance variability at the interannual to decadal time scale. Precipitation did not display a significant trend in the tropical Andes in the 20th century, and consequently cannot explain the glacier recession. On the other hand, temperature increased at a significant rate of 0.10 °C decade−1 in the last 70 yr. The higher frequency of El Niño events and changes in its spatial and temporal occurrence since the late 1970s together with a warming troposphere over the tropical Andes may thus explain much of the

  6. Bed topography under Antarctic outlet glaciers revealed by mass conservation and radar data

    Science.gov (United States)

    Morlighem, M.; Rignot, E. J.; Mouginot, J.; Seroussi, H. L.

    2015-12-01

    Bed topography, together with ice thickness, is an essential characteristic of glaciers and ice sheets for many glaciological applications. Despite significant technical advances, it remains challenging to measure ice thickness remotely, especially in deep troughs occupied by outlet glaciers. The method of mass conservation, that combines radar-derived ice thickness data with high-resolution InSAR-derived ice velocity vectors, provides an effective method for generating a high-resolution bed from sparse radar sounding profiles, and has been successfully applied along the coast of the Greenland Ice Sheet. Applying the same technique to the coast of the Antarctic Ice Sheet presents a number of challenges. The coverage of ice thickness data collected in Antarctica, for example, is much less comprehensive compared to Greenland, especially in the wake of NASA's Operation IceBridge (OIB) Mission in 2010-2015. Here, we combine radar sounder data collected by various centers (OIB/Center for Remote Sensing of Ice Sheets, the British Antarctic Survey and University of Texas) acquired between 1998 and 2011, with high-resolution ice motion data from interferometric SAR (ALOS PALSAR, RADARSAT-2 and Envisat ASAR) to reconstruct bed topography beneath major Antarctic outlet glaciers at an unprecedented level of detail. The results reveal some important features not known previously at that level of detail and shed light on the vulnerability of these glaciers in a warming climate. We find for example that Recovery glacier is deeper than in previous mappings and has long grooves parallel to the flow direction. Denman Glacier, East Antarctica, flow along a deep, narrow trough more than 2,000 m below sea level that extends more than 100 km inland. We find ridges and bumps in the vicinity of the grounding line of Thwaites Glacier, in the Amundsen Sea sector, that are consistent with the pattern of grounding line retreat. We have also a new mapping of the trough upstream of David

  7. Educating K-12 Students about Glacier Dynamics in a Changing Climate

    Science.gov (United States)

    Stearns, L. A.; Hamilton, G. S.

    2005-12-01

    Public awareness of climate change is growing in the United States. Popular movies, books and magazines are frequently addressing the issue of global warming - some with careful scientific research, but many with unrealistic statements. Early education about the basic principles and processes of climate change is necessary for the general public to distinguish fact from fiction. The U.S. National Science Foundation's GK-12 program (GK-12; grades K to 12) currently in its sixth year, provides an opportunity for scientific enrichment for students and their teachers at the K-12 level through collaborative pairings with science and engineering graduate students (the Fellows). The NSF GK-12 program at the University of Maine has three goals: to enrich the scientific education of the students by providing role models, expertise, and equipment that may not be accessible otherwise; to provide professional development for the teachers through curriculum enrichment and participation at science conferences; and to improve the teaching and communication skills of the Fellows. The University of Maine is one of over 100 U. S. universities participating in this program. During the 2004-05 academic year, 11 graduate and one undergraduate student Fellows, advised by University faculty members, taught at schools across the state of Maine. Fellows from, biology, earth science, ecology, engineering, food science, forestry, and marine science, and taught in their area of expertise. We created a hands-on activity for middle and high school students that describes glacier mass balance in a changing climate. The students make a glacier using glue, water and detergent ('flubber') and construct a glacier valley using plastic sheeting. Flubber behaves in mechanically similar ways to glacier ice, undergoing plastic deformation at low stresses and exhibiting brittle failure at high stresses. Students are encouraged to run several tests with different values for valley slope, glacier mass

  8. 20 years of mass balances on the Piloto glacier, Las Cuevas river basin, Mendoza, Argentina

    Science.gov (United States)

    Leiva, J. C.; Cabrera, G. A.; Lenzano, L. E.

    2007-10-01

    Climatic changes of the 20th century have altered the water cycle in the Andean basins of central Argentina. The most visible change is seen in the mountain glaciers, with loss of part of their mass due to decreasing thickness and a substantial recession in the last 100 years. This paper briefly describes the results of glacier mass balance research since 1979 in the Piloto Glacier at the Cajón del Rubio, in the headwaters of Las Cuevas River, presenting new results for the period 1997-2003. Very large interannual variability of net annual specific balance is evident, due largely to variations in winter snow accumulation, with a maximum net annual value of + 151 cm w.e. and a minimum value of - 230 cm w.e. Wet El Niño years are normally associated with positive net annual balances, while dry La Niña years generally result in negative balances. Within the 24-year period, 67% of the years show negative net annual specific balances, with a cumulative mass balance loss of - 10.50 m water equivalent (w.e.). Except for exceptions normally related to El Niño events, a general decreasing trend of winter snow accumulation is evident in the record, particularly after 1992, which has a strong effect in the overall negative mass balance values. The glacier contribution to Las Cuevas River runoff is analysed based on the Punta de Vacas River gauge station for a hypothetical year without snow precipitation (YWSP), when the snowmelt component is zero. Extremely dry years similar to a YWSP have occurred in 1968-1969, 1969-1970 and 1996-1997. The Punta de Vacas gauge station is located 62 km downstream from Piloto Glacier, and the basin contains 3.0% of uncovered glacier ice and 3.7% of debris-covered ice. The total glacier contribution to Las Cuevas River discharge is calculated as 82 ± 8% during extremely dry years. If glacier wastage continues at the present trend as observed during the last 2 decades, it will severely affect the water resources in the arid central Andes of

  9. Midlatitude Forcing Mechanisms for Glacier Mass Balance Investigated Using General Circulation Models

    NARCIS (Netherlands)

    Reichert, B.K.; Bengtsson, L.; Oerlemans, J.

    2001-01-01

    A process-oriented modeling approach is applied in order to simulate glacier mass balance for individual glaciers using statistically downscaled general circulation models (GCMs). Glacier-specific seasonal sensitivity characteristics based on a mass balance model of intermediate complexity are used

  10. Extrapolating glacier mass balance to the mountain-range scale: the European Alps 1900–2100

    OpenAIRE

    Huss, M.

    2012-01-01

    This study addresses the extrapolation of in-situ glacier mass balance measurements to the mountain-range scale and aims at deriving time series of area-averaged mass balance and ice volume change for all glaciers in the European Alps for the period 1900–2100. Long-term mass balance series for 50 Swiss glaciers based on a combination of field data and modelling, and WGMS data for glaciers in Austria, France and Italy are used. A complete glacier inventory is available for the year 2003. Mass ...

  11. Recent accelerating mass loss of southeast Tibetan glaciers and the relationship with changes in macroscale atmospheric circulations

    Science.gov (United States)

    Yang, Wei; Guo, Xiaofeng; Yao, Tandong; Zhu, Meilin; Wang, Yongjie

    2016-08-01

    The mass balance history (1980-2010) of a monsoon-dominated glacier in the southeast Tibetan Plateau is reconstructed using an energy balance model and later interpreted with regard to macroscale atmospheric variables. The results show that this glacier is characterized by significant interannual mass fluctuations over the past three decades, with a remarkably high mass loss during the recent period of 2003-2010. Analysis of the relationships between glacier mass balance and climatic variables shows that interannual temperature variability in the monsoonal season (June-September) is a primary driver of its mass balance fluctuations, but monsoonal precipitation tends to play an accentuated role for driving the observed glacier mass changes due to their covariation (concurrence of warm/dry and cold/wet climates) in the monsoon-influenced southeast Tibetan Plateau. Analysis of the atmospheric circulation pattern reveals that the predominance of anticyclonic/cyclonic circulations prevailing in the southeastern/northern Tibetan Plateau during 2003-2010 contributes to increased air temperature and decreased precipitation in the southeast Tibetan Plateau. Regionally contrasting atmospheric circulations explain the distinct mass changes between in the monsoon-influenced southeast Tibetan Plateau and in the north Tibetan Plateau/Tien Shan Mountains during 2003-2010. The macroscale climate change seems to be linked with the Europe-Asia teleconnection.

  12. Holocene and latest Pleistocene climate and glacier fluctuations in Iceland

    Science.gov (United States)

    Geirsdóttir, Áslaug; Miller, Gifford H.; Axford, Yarrow; Ólafsdóttir, Sædís

    2009-10-01

    Multiproxy climate records from Iceland document complex changes in terrestrial climate and glacier fluctuations through the Holocene, revealing some coherent patterns of change as well as significant spatial variability. Most studies on the Last Glacial Maximum and subsequent deglaciation reveal a dynamic Iceland Ice Sheet (IIS) that responded abruptly to changes in ocean currents and sea level. The IIS broke up catastrophically around 15 ka as the Polar Front migrated northward and sea level rose. Indications of regional advance or halt of the glaciers are seen in late Alleröd/early Younger Dryas time and again in PreBoreal time. Due to the apparent rise of relative sea level in Iceland during this time, most sites contain evidence for fluctuating, tidewater glacier termini occupying paleo fjords and bays. The time between the end of the Younger Dryas and the Preboreal was characterized by repeated jökulhlaups that eroded glacial deposits. By 10.3 ka, the main ice sheet was in rapid retreat across the highlands of Iceland. The Holocene thermal maximum (HTM) was reached after 8 ka with land temperatures estimated to be 3 °C higher than the 1961-1990 reference, and net precipitation similar to modern. Such temperatures imply largely ice-free conditions across Iceland in the early to mid-Holocene. Several marine and lacustrine sediment climate proxies record substantial summer temperature depression between 8.5 and 8 ka, but no moraines have been detected from that time. Termination of the HTM and onset of Neoglacial cooling took place sometime after 6 ka with increased glacier activity between 4.5 and 4.0 ka, intensifying between 3.0 and 2.5 ka. Although a distinct warming during the Medieval Warm Period is not dramatically apparent in Icelandic records, the interval from ca AD 0 to 1200 is commonly characterized by relative stability with slow rates of change. The literature most commonly describes Little Ice Age moraines (ca AD 1250-1900) as representing the

  13. Glaciers

    Institute of Scientific and Technical Information of China (English)

    Philip Hughes

    2006-01-01

    @@ This book is the second and expanded volume of Glaciers, the first published in 1992.The second edition contains four more chapters and the whole text has been fully revised.The book is divided into sixteen chapters logically progressing from an outline of ice on Earth through various chapters detailing the nature of glaciers and their environments supported by an array of magnificent colour photographs and examples.

  14. The Mass Balance of Glacier No. 1 at the Headwaters of the Urumqi River in Relation to Northern Hemisphere Teleconnection Patterns

    Directory of Open Access Journals (Sweden)

    Feifei Yuan

    2016-03-01

    Full Text Available Most small glaciers in the world have significantly decreased their volume during the last century, which has caused water shortage problems. Glacier No. 1, at the headwaters of the Urumqi River, Tianshan, China, has been monitored since 1959 and similarly has experienced significant mass and volume losses over the last few decades. Thus, we examined the trend and potential abrupt changes of the mass balance of Glacier No. 1. Principal component analysis and singular value decomposition were used to find significant relations between the mass balance of Glacier No. 1 and Northern Hemisphere teleconnection patterns using climate indices. It was found that the mass balance of Glacier No. 1 had a significantly decreasing trend corresponding to −14.5 mm/year from 1959 to 2010. A change point was detected in 1997 with 99% confidence level. Two time periods with different mass balances were identified as 1959–1996 and 1997–2010. The mass balance for the first period was −136.4 mm/year and up to −663.9 mm/year for the second period. The mass balance of Glacier No. 1 is positively related to the Scandinavian Pattern (SCA, and negatively related to the East Atlantic Pattern (EA. These relationships are useful in better understanding the interaction between glacier mass balance and climate variability.

  15. Reconciling high-altitude precipitation in the upper Indus basin with glacier mass balances and runoff

    Science.gov (United States)

    Immerzeel, Walter; Wanders, Niko; Lutz, Arthur; Shea, Joseph; Bierkens, Marc

    2016-04-01

    Mountain ranges in Asia are important water suppliers, especially if downstream climates are arid, water demands are high and glaciers are abundant. In such basins, the hydrological cycle depends heavily on high-altitude precipitation. Yet direct observations of high-altitude precipitation are lacking and satellite derived products are of insufficient resolution and quality to capture spatial variation and magnitude of mountain precipitation. Here we use glacier mass balances to inversely infer the high-altitude precipitation in the upper Indus basin and show that the amount of precipitation required to sustain the observed mass balances of large glacier systems is far beyond what is observed at valley stations or estimated by gridded precipitation products. An independent validation with observed river flow confirms that the water balance can indeed only be closed when the high altitude precipitation on average is more than twice as high and in extreme cases up to a factor of 10 higher than previously thought. We conclude that these findings alter the present understanding of high-altitude hydrology and will have an important bearing on climate change impact studies, planning and design of hydropower plants and irrigation reservoirs as well as the regional geopolitical situation in general.

  16. On the use of the point-mass modeling technique for assessing ice-mass variations in alpine glacier systems

    Science.gov (United States)

    Reimond, Stefan; Baur, Oliver; Krauss, Sandro

    2016-04-01

    Most scientific studies dealing with gravity-based ice-mass balance estimations focus on the Earth's continental glacier systems, namely the Greenland and the Antarctica ice sheets. Alpine glacier regions such as the Alps, Himalaya or Patagonia, on the other hand, seem to be less considered. According to the most recent assessment report of the Intergovernmental Panel on Climate Change (IPCC), however, glacier shrinkage is one of the most dominant contributors to global sea level rise. In this context we investigate the capability of the point-mass modeling technique to assess ice-mass variations in small-scale alpine regions from space-borne gravimetric data. Two different approaches of this method can be distinguished: point-mass modeling with (i) predefined and fixed positions and (ii) with unknown locations of the surface mass changes. Approach (i) yields a linear functional model in which only the magnitudes of the point-masses are considered unknown. A highly non-linear optimization problem needs to be solved for approach (ii), since both the magnitudes and the coordinates of the point-masses are introduced as unknown parameters. In addition to that, owing to the effect of downward continuation, this problem is categorized as ill-posed and needs to be remedied by introducing regularization. The L-curve criterion or the generalized cross-validation method are typically used for selecting a suitable regularization factor. We conducted a series of close-loop simulation tests for various alpine glacier systems to compare the two approaches. In order to solve the global optimization problems in (i) and (ii), we make use of genetic algorithms.

  17. Glacier-derived climate for the Younger Dryas in Europe

    Science.gov (United States)

    Pellitero, Ramon; Rea, Brice R.; Spagnolo, Matteo; Hughes, Philip; Braithwaite, Roger; Renssen, Hans; Ivy-Ochs, Susan; Ribolini, Adriano; Bakke, Jostein; Lukas, Sven

    2016-04-01

    We have reconstructed and calculated the glacier equilibrium line altitudes (ELA) for 120 Younger Dryas palaeoglaciers from Morocco in the south to Svalbard in the north and from Ireland in the west to Turkey in the east. The chronology of these landform were checked and, when derived from cosmogenic dates, these were recalculated based on newer production rates. Frontal moraines/limits for the palaeoglaciers were used to reconstruct palaeoglacier extent by using a GIS tool which implements a discretised solution for the assumption of perfect-plasticity ice rheology for a single flowline and extents this out to a 3D ice surface. From the resulting equilibrium profile, palaeoglaciers palaeo-ELAs were calculated using another GIS tool. Where several glaciers were reconstructed in a region, a single ELA value was generated following the methodology of Osmaston (2005). In order to utilise these ELAs for quantitative palaeo-precipitation reconstructions an independent regional temperature analysis was undertaken. A database of 121 sites was compiled where the temperature was determined from palaeoproxies other than glaciers (e.g. pollen, diatoms, choleoptera, chironimids…) in both terrestrial and offshore environments. These proxy data provides estimates of average annual, summer and winter temperatures. These data were merged and interpolated to generate maps of average temperature for the warmest and coldest months and annual average temperature. From these maps the temperature at the ELA was obtained using a lapse rate of 0.65°C/100m. Using the ELA temperature range and summer maximum in a degree-day model allows determination of the potential melt which can be taken as equivalent to precipitation given the assumption a glacier is in equilibrium with climate. Results show that during the coldest part of the Younger Dryas precipitation was high in the British Isles, the NW of the Iberian Peninsula and the Vosges. There is a general trend for declining precipitation

  18. Reconstructing glacier-based climates of LGM Europe and Russia – Part 3: Comparison with GCM and pollen-based climate reconstructions

    Directory of Open Access Journals (Sweden)

    A. J. Payne

    2007-10-01

    Full Text Available Understanding past climates using GCM models is critical to confidently predicting future climate change. Although previous analysis of GCM simulations have shown them to under predicted European glacial temperature anomalies (the difference between modern and glacial temperatures such analyses have focused primarily on results from glacial simulations alone. Here we compare glacial maximum GCM results with the palaeoenvironment derived from glacier-climate modelling. The comparison confirms that GCM anomalies are under predicted, and that this is due to modern conditions that are modelled too cold and glacial temperatures that are too warm. The result is that CGM results, if applied to a glacier mass balance model, over predict the extent of glaciers today, and under predict their extent at the last glacial (as depicted in glacial geological reconstructions. Effects such as seasonality and model parameterisation change the magnitude of the under prediction but still fail to match expected glacial conditions.

  19. Glacial changes and glacier mass balance at Gran Campo Nevado, Chile during recent decades

    Science.gov (United States)

    Schneider, C.; Schnirch, M.; Kilian, R.; Acuña, C.; Casassa, G.

    2003-04-01

    Within the framework of the program Global Land Ice Measurements from Space (GLIMS) a glacier inventory of the Peninsula Muñoz Gamero in the southernmost Andes of Chile (53°S) has been generated using aerial photopgrahy and Landsat Thematic Mapper imagery. The Peninsula is partly covered by the ice cap of the Gran Campo Nevado (GCN), including several outlet glaciers plus some minor glaciers and firn fields. All together the ice covered areas sum up to 260 km2. GCN forms the only major ice body between the Southern Patagonia Icefield and the Strait of Magallan. Its almost unique location in a zone affected year-round by the westerlies makes it a region of key interest in terms of glacier and climate change studies of the west-wind zone of the Southern Hemisphere. A digital elevation model (DEM) was created for the area, using aerial imagery from 1942, 1984, and 1998 and a Chilean topographic map (1: 100 000). All information was incorporated into a GIS together with satellite imagery from 1986 and 2001. Delineation of glacier inflow from the central plateau of Gran Campo Nevado was accomplished using an automatic module for watershed delineation within the GIS. The GIS served to outline the extent of the present glaciation of the peninsula, as well as to evaluate the derived historic information. The comparison of historic and recent imagery reveals a dramatic glacier retreat during the last 60 years. Some of the outlet glaciers lost more than 20% of their total area during this period. In February and March 2000 a automatic weather station (AWS) was run on a nameless outlet glacier, inofficially Glaciar Lengua, of the Gran Campo Nevado Ice Cap. From the computed energy balance, it was possible to derive degree-day factors for the Glaciar Lengua. With data from the nearby AWS at fjord coast (Bahia Bahamondes) we computed ablation for the summer seasons of 1999/2000, 2000/2001 and 2001/2002. Ablation at 450 m a.s.l. sums up to about 7 m in 1999/2000, 5.5 m in 2000

  20. Modeling mass balance and volume of Xiao Dongkemadi glacier in the Central Tibetan Plateau from 1989 to 2050

    Science.gov (United States)

    Duan, K.

    2015-12-01

    The Tibetan Plateau (TP) holds ten thousands of alpine glaciers in mid-latitude, which have shrunk with an accelerating retreat rate recently. Here, we applied a temperature-index distributed mass-balance model coupled with a volume-area scaling method to Xiao Dongkemadi Glacier (XDG) in the central TP, to assess its response to climate change. The result shows the simulated mass balance is in a good agreement with observations (R2=0.75, p<0.001) during the period of 1989-2012. The simulated mean annual mass balance (-213 mm w.e.) is close to the observation (-233 mm w.e.), indicating the model can be used to estimate the glacier variation in the future. Then the model was forced by the output of RegCM4 under the climate scenarios RCP4.5 and RCP8.5 from 2013 to 2050. The simulated terminus elevation of the glacier will rise from 5454m a.s.l. in 2013 to 5533m a.s.l. (RCP4.5) and 5543m a.s.l (RCP8.5) in 2050. XDG will lose its volume with an increasing rate of 600-700m3 a-1 during the period of 1989-2050, indicating the melting water will enhance the river runoff. But for the long term, the contribution to the river runoff will decrease for shrinkage of glacier scale.

  1. Meteorological and climatological feature around Potanin glacier, Mongolian Altai

    OpenAIRE

    紺屋, 恵子; 門田, 勤; 矢吹, 裕伯; Davaa, Gombo; Purevdagva, Khalzan; 大畑, 哲夫

    2010-01-01

    Fluctuation of glacier mass balance can be an indicator of climate change. Also, discharge from a glacier is necessary for water resources in arid region because glacier melt water is quasi-sustainable water resource. Asian glaciers show outstanding negative trend. There are many glaciers in Altai mountain range. It is revealed that glaciers in western Mongolia are retreating by Satellite image (Kadota and Gombo, 2007). However, less information has been obtained for Mongolian Altai because ...

  2. Cloud effects on the surface energy and mass balance of Brewster Glacier, New Zealand

    Directory of Open Access Journals (Sweden)

    J. P. Conway

    2015-02-01

    Full Text Available A thorough understanding of the influence of clouds on glacier surface energy balance (SEB and surface mass balance (SMB is critical for forward and backward modelling of glacier–climate interactions. A validated 22 month time series of SEB/SMB was constructed for the ablation zone of the Brewster Glacier, using high quality radiation data to carefully evaluate SEB terms and define clear-sky and overcast conditions. A fundamental change in glacier SEB in cloudy conditions was driven by increased effective sky emissivity and surface vapour pressure, rather than the minimal change in air temperature and wind speed. During overcast conditions, positive net longwave radiation and latent heat fluxes allowed melt to be maintained through a much greater length of time compared to clear-sky conditions, and led to similar melt in each sky condition. The sensitivity of SMB to changes in air temperature was greatly enhanced in overcast compared to clear-sky conditions due to more frequent melt and the occurrence of precipitation, which enabled a strong accumulation–albedo feedback. During the spring and autumn seasons, the sensitivity during overcast conditions was strongest. There is a need to include the effects of atmospheric moisture (vapour, cloud and precipitation on melt processes when modelling glacier–climate interactions.

  3. Re-analysis of seasonal mass balance at Abramov glacier 1968–2014

    OpenAIRE

    Martina Barandun; Matthias Huss; Leo Sold; D. Farinotti; Erlan Azisov; Nadine Salzmann; Ryskul Usubaliev; Alexandr Merkushkin; Martin Hoelzle

    2016-01-01

    Abramov glacier, located in the Pamir Alay, Kyrgyzstan, is a reference glacier within the Global Terrestrial Network for Glaciers. Long-term glaciological measurements exist from 1968 to 1998 and a mass-balance monitoring programme was re-established in 2011. In this study we re-analyse existing mass-balance data and use a spatially distributed mass-balance model to provide continuous seasonal time series of glacier mass balance covering the period 1968–2014. The model is calibrated to season...

  4. Estimation of glacier mass balance: An approach based on satellite-derived transient snowlines and a temperature index driven by meteorological observations

    Science.gov (United States)

    Tawde, S. A.; Kulkarni, A. V.; Bala, G.

    2015-12-01

    In the Himalaya, large area is comprised of glaciers and seasonal snow, mainly due to its high elevated mountain ranges. Long term and continuous assessment of glaciers in this region is important for climatological and hydrological applications. However, rugged terrains and severe weather conditions in the Himalaya lead to paucity in field observations. Therefore, in recent decades, glacier dynamics are extensively monitored using remote sensing in inaccessible terrain like Himalaya. Estimation of glacier mass balance using empirical relationship between mass balance and area accumulation ratio (AAR) requires an accurate estimate of equilibrium-line altitude (ELA). ELA is defined as the snowline at the end of the hydrological year. However, identification of ELA, using remote sensing is difficult because of temporal gaps, cloud cover and intermediate snowfall on glaciers. This leads to large uncertainty in glacier mass-balance estimates by the conventional AAR method that uses satellite-derived highest snowline in ablation season as an ELA. The present study suggests a new approach to improve estimates of ELA location. First, positions of modelled snowlines are optimized using satellite-derived snowlines in the early melt season. Secondly, ELA at the end of the glaciological year is estimated by the melt and accumulation models driven using in situ temperature and precipitation records. From the modelled ELA, mass balance is estimated using the empirical relationship between AAR and mass balance. The modelled mass balance is validated using field measurements on Chhota Shigri and Hamtah glaciers, Himachal Pradesh, India. The new approach shows a substantial improvement in glacier mass-balance estimation, reducing bias by 46% and 108% for Chhota Shigiri and Hamtah glaciers respectively. The cumulative mass loss reconstructed from our approach is 0.85 Gt for nine glaciers in the Chandra basin from 2001 to 2009. The result of the present study is in agreement with

  5. The climate memory of an Arctic polythermal glacier

    OpenAIRE

    Delcourt, C.; B. Van Liefferinge; M. Nolan; F. Pattyn

    2013-01-01

    Knowledge of glacier equilibrium-line altitude (ELA) changes and trends in time is essential for future predictions of glacier volumes. We present a novel method for determining trends in ELA change at McCall Glacier, Alaska, USA, over the last 50 years, based on mapping of the cold temperate transition surface (CTS), marking the limit between cold and temperate ice of a polythermal glacier. Latent heat release from percolating meltwater and precipitation keeps the ice column temperate in the...

  6. Extracting a climate signal from 169 glacier records

    NARCIS (Netherlands)

    Oerlemans, J.

    2005-01-01

    I constructed a temperature history for different parts of the world from 169 glacier length records. Using a first-order theory of glacier dynamics, I related changes in glacier length to changes in temperature. The derived temperature histories are fully independent of proxy and instrumental data

  7. Interannual to decadal time-scale variations in glacier mass balance [abstract

    OpenAIRE

    Walters, Roy A.

    1996-01-01

    EXTRACT (SEE PDF FOR FULL ABSTRACT): The mass balance of glaciers depends on the seasonal variation in precipitation, temperature, and insolation. For glaciers in western North America, these meteorological variables are influenced by the large-scale atmospheric circulation over the northern Pacific Ocean. The purpose of this study is to gain a better understanding of the relationship between mass balance at glaciers in western North America and the large-scale atmospheric effects at inte...

  8. Sensitivity of Glaciers and Small Ice Caps to Greehouse Warming

    NARCIS (Netherlands)

    Oerlemans, J.; Fortuin, J.P.F.

    1992-01-01

    Recent field programs on glaciers have supplied information that makes simulation of glacier mass balance with meteorological models meaningful. An estimate of world-wide glacier sensitivity based on a modeling study of 12 selected glaciers situated in widely differing climatic regimes shows that fo

  9. Mass balance and surface velocity reconstructions of two reference Caucasus glaciers

    Science.gov (United States)

    Rybak, Oleg; Kaminskaia, Mariia; Kutuzov, Stanislav; Lavrentiev, Ivan; Morozova, Polina; Popovnin, Victor; Rybak, Elena

    2016-04-01

    Total glacial volume of the Greater Caucasus exceeds 40 cubic km and its area exceeds 1 thousand square km. During the 20th century, mountain glaciers at the Greater Caucasus were continuously degrading. According to various estimates, their area reduced more than one-third and their volume almost by half. The process of degradation was accompanied by growing population and economical development on surrounding territories. In the 21st century under proceeding global warming, a tendency of shrinking of area and volume of glaciation is obviously expected to continue. Working out of strategy of sustainable economic development of the region is the main motivation for elaboration of predictions of glaciers' evolution in the changing environment. Growing demand of fresh water is the basic challenge for the local economy, and efficient planning of water resources is impossible without knowing future state of glaciation. Therefore our research aims at obtaining accurate evaluation of probable future change of the most prominent mountain glaciers of the Greater Caucasus in forthcoming decades and at studying impacts of changing characteristics of glaciation on the run-off in the area. Initially, we focus on two so-called reference glaciers - Marukh (Western Caucasus) and Djankuat (Central Caucasus). Intensive field observations on both of them have been conducted during the last half of the century and essential amount of detailed relevant information has been collected on their geometry change and on mass balance. Besides, meteorological measurements were episodically carried out directly on the glaciers providing enough data for correlation of the local weather conditions with the data from the closest meteorological stations. That is why studying of response of Marukh and Djankuat on the environmental change can be accurately verified, which is crucial for understanding mechanisms driving evolution of large glaciated area in the Caucasus. As the instrument of research

  10. Greenland surface mass-balance observations from the ice-sheet ablation area and local glaciers

    DEFF Research Database (Denmark)

    Machguth, Horst; Thomsen, Henrik; Weidick, Anker;

    2016-01-01

    Glacier surface mass-balance measurements on Greenland started more than a century ago, but no compilation exists of the observations from the ablation area of the ice sheet and local glaciers. Such data could be used in the evaluation of modelled surface mass balance, or to document changes in g...

  11. Glacier crevasses: Observations, models, and mass balance implications

    Science.gov (United States)

    Colgan, William; Rajaram, Harihar; Abdalati, Waleed; McCutchan, Cheryl; Mottram, Ruth; Moussavi, Mahsa S.; Grigsby, Shane

    2016-03-01

    We review the findings of approximately 60 years of in situ and remote sensing studies of glacier crevasses, as well as the three broad classes of numerical models now employed to simulate crevasse fracture. The relatively new insight that mixed-mode fracture in local stress equilibrium, rather than downstream advection alone, can introduce nontrivial curvature to crevasse geometry may merit the reinterpretation of some key historical observation studies. In the past three decades, there have been tremendous advances in the spatial resolution of satellite imagery, as well as fully automated algorithms capable of tracking crevasse displacements between repeat images. Despite considerable advances in developing fully transient three-dimensional ice flow models over the past two decades, both the zero stress and linear elastic fracture mechanics crevasse models have remained fundamentally unchanged over this time. In the past decade, however, multidimensional and transient formulations of the continuum damage mechanics approach to simulating ice fracture have emerged. The combination of employing damage mechanics to represent slow upstream deterioration of ice strength and fracture mechanics to represent rapid failure at downstream termini holds promise for implementation in large-scale ice sheet models. Finally, given the broad interest in the sea level rise implications of recent and future cryospheric change, we provide a synthesis of 10 mechanisms by which crevasses can influence glacier mass balance.

  12. Reconstructing mass balance of Garabashi Glacier (1800–2005 using dendrochronological data

    Directory of Open Access Journals (Sweden)

    E. A. Dolgova

    2013-01-01

    Full Text Available The exploration whether tree-ring data can be effectually applied for the mass balance reconstruction in Caucasus was the main goal of this research. Tree-ring width and maximum density chronologies of pine (Pinus sylvestris L. at seven high-elevation sites in Northern Caucasus were explored for this purpose. As well as in other places of the temperate zone tree- ring width has complex climate signal controlled both temperature and precipitation. Instrumental mass balance records of Garabashi Gglacier started at 1983s. It is well known that Caucasus glaciers intensively retreat in the last decades and according to instrumental data mass balance variations are mostly controlled by the ablation, i.e. summer temperature variations. Maximum density chronology has statistically significant correlation with mass balance due to summer temperature sensitivity and great input of ablation to total mass balance variations. To include in our reconstruction different climatically sensitive parameters, stepwise multiple regression model was used. The strongest relation (r = 0.88; r2 = 0.78; p < 0.05 between two ring-width and one maximum density chronologies was identified. Cross-validation test (r = 0.79; r2 = 0.62; p < 0.05 confirmed model adequacy and it allowed to reconstruct Garabashi Glacier mass balance for 1800–2005ss. Reconstructed and instrumental mass balance values coincide well except the most recent period in 2000s, when the reconstructed mass balance slightly underestimated the real values. However even in this period it remained negative as well as the instrumental records. The bias can be explained by the weak sensitivity of the chronologies to winter precipitation (i.e. accumulation. The tree-ring based mass balance reconstruction was compared with one based on meteorological data (since 1905s. Both reconstructions have good interannual agreement (r = 0.53; p < 0.05 particularly for the period between 1975 and 2005. According to the

  13. Dramatic mass loss in extreme high-elevation areas of a western Himalayan glacier: observations and modeling.

    Science.gov (United States)

    Zhao, Huabiao; Yang, Wei; Yao, Tandong; Tian, Lide; Xu, Baiqing

    2016-01-01

    Rapid climate change at high elevations has accelerated glacier retreat in the Himalayas and Tibetan Plateau. However, due to the lack of long-term glaciological measurements, there are still uncertainties regarding when the mass loss began and what the magnitude of mass loss is at such high elevations. Based on in situ glaciological observations during the past 9 years and a temperature-index mass balance model, this study investigates recent mass loss of the Naimona'nyi Glacier in the western Himalayas and reconstructs a 41-year (1973/74-2013/14) equilibrium line altitude (ELA) and glacier-wide mass loss. The result indicates that even at 6000 m above sea level (a.s.l.), the annual mass loss reaches ~0.73 m water equivalent (w.e.) during the past 9 years. Concordant with the abrupt climate shift in the end of 1980s, the ELA has dramatically risen from ~5969 ± 73 m a.s.l. during 1973/74-1988/89 to ~6193 ± 75 m a.s.l. during 1989/90-2013/14, suggesting that future ice cores containing uninterrupted climate records could only be recovered at least above 6200 m a.s.l. in the Naimona'nyi region. The glacier-wide mass balance over the past 41 years is averaged to be approximately -0.40 ± 0.17 m w.e., exhibiting a significant increase in the decadal average from -0.01 ± 0.15 to -0.69 ± 0.21 m w.e. PMID:27561411

  14. Dramatic mass loss in extreme high-elevation areas of a western Himalayan glacier: observations and modeling

    Science.gov (United States)

    Zhao, Huabiao; Yang, Wei; Yao, Tandong; Tian, Lide; Xu, Baiqing

    2016-08-01

    Rapid climate change at high elevations has accelerated glacier retreat in the Himalayas and Tibetan Plateau. However, due to the lack of long-term glaciological measurements, there are still uncertainties regarding when the mass loss began and what the magnitude of mass loss is at such high elevations. Based on in situ glaciological observations during the past 9 years and a temperature-index mass balance model, this study investigates recent mass loss of the Naimona’nyi Glacier in the western Himalayas and reconstructs a 41-year (1973/74–2013/14) equilibrium line altitude (ELA) and glacier-wide mass loss. The result indicates that even at 6000 m above sea level (a.s.l.), the annual mass loss reaches ~0.73 m water equivalent (w.e.) during the past 9 years. Concordant with the abrupt climate shift in the end of 1980s, the ELA has dramatically risen from ~5969 ± 73 m a.s.l. during 1973/74–1988/89 to ~6193 ± 75 m a.s.l. during 1989/90–2013/14, suggesting that future ice cores containing uninterrupted climate records could only be recovered at least above 6200 m a.s.l. in the Naimona’nyi region. The glacier-wide mass balance over the past 41 years is averaged to be approximately ‑0.40 ± 0.17 m w.e., exhibiting a significant increase in the decadal average from ‑0.01 ± 0.15 to ‑0.69 ± 0.21 m w.e.

  15. Estimating the avalanche contribution to the mass balance of debris covered glaciers

    OpenAIRE

    Banerjee, A.; Shankar, R.

    2014-01-01

    Avalanche from high head walls dominates the net accumulation in many debris covered glaciers in the Himalaya. These avalanche contributions are difficult to directly measure and may cause a systematic bias in glaciological mass balance measurements. In this paper we develop a method to estimate the avalanche contribution using available data, within the context of an idealised flowline model of the glacier. We focus on Hamtah glacier in Western Himalaya ...

  16. Sensitivity of glacier runoff projections to baseline climate data in the Indus River Basin

    Directory of Open Access Journals (Sweden)

    Michele eKoppes

    2015-10-01

    Full Text Available Quantifying the contribution of glacier runoff to water resources is particularly important in regions such High Mountain Asia, where glaciers provide a large percentage of seasonal river discharge and support large populations downstream. In remote areas, direct field measurements of glacier melt rates are difficult to acquire and rarely observed, so hydro-glaciological modeling and remote sensing approaches are needed. Here we present estimates of glacier melt contribution to the Upper Indus watershed over the last 40 years using a suite of seven reanalysis climate datasets that have previously been used in hydrological models for this region, a temperature-index melt model and > 29,000 km2 of ice cover. In particular, we address the uncertainty in estimates of meltwater flux that is introduced by the baseline climate dataset chosen, by comparing the results derived from each. Mean annual glacier melt contribution varies from 8 km3 yr-1 and 169 km3 yr-1, or between 4-78% of the total annual runoff in the Indus, depending on temperature dataset applied. Under projected scenarios of an additional 2-4°C of regional warming by 2100 AD, we find annual meltwater fluxes vary by >200% depending on the baseline climate dataset used and, importantly, span a range of positive and negative trends. Despite significant differences between climate datasets and the resulting spread in meltwater fluxes, the spatial pattern of melt is highly correlated and statistically robust across all datasets. This allows us to conclude with confidence that fewer than 10% of the >20,000 glaciers in the watershed contribute more than 80% of the total glacier runoff to the Indus. These are primarily large, low elevation glaciers in the Karakoram and Hindu Kush. Additional field observations to ground-truth modeled climate data will go far to reduce the uncertainty highlighted here and we suggest that efforts be focused on those glaciers identified to be most significant to

  17. Isotopic and chemical analyses of a temperate firn core from a Chinese alpine glacier and its regional climatic significance

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Mt. Yulong is the southernmost currently glacier-covered area in Eurasia, including China. There are 19 sub-tropical temperate glaciers on the mountain, controlled by the south-western monsoon climate. In the summer of 1999, a firn core, 10. 10 m long, extending down to glacier ice, was recovered in the accumulation area of the largest glacier, Baishui No. 1. Periodic variations of climatic signals above 7. 8 m depth were apparent, and net accumulation of four years was identified by the annual oscillations of isotopic and ionic composition. The boundaries of annual accumulation were confirmed by higher values of electrical conductivity and pH, and by dirty refreezing ice layers at the levels of summer surfaces. Calculated mean annual net accumulation from 1994/1995 to 1997/1998 was about 900 mm water equivalent. The amplitude of isotopic variations in the profile decreased with increasing depth, and isotopic homogenization occurred below 7. 8 m as a result of meltwater percolation. Variations of δ18O above 7. 8 m showed an approximate correlation with the winter climatic trend at Li Jiang Station, 25 km away. Concentrations of Ca2+ and Mg2+ were much higher than those of Na+ and K+ , indicating that the air masses for precipitation were mainly from a continental source, and that the core material accumulated during the winter period. The close correspondence of C1- and Na+ indicated their common origin. Very low concentrations of SO2-4 and NO3- suggest that pollution caused by human activities is quite low in the area. The mean annual net accumulation in the core and the estimated ablation indicate that the average annual precipitation above the glacier's equilibrium line is 2400 - 3150 mm, but this needs to be confirmed by long term observation of mass balance.

  18. Relative importance of glacier contributions to streamflow in a changing climate

    Science.gov (United States)

    The role of glaciers and snow in climate change-affected runoff is evaluated by taking into account the carryover of runoff and of unmelted snow from one hydrological year to another. This water balance is computed for the present climate and for future climates with changed temperatures and precip...

  19. Modeling the variation trends of glacier systems

    Directory of Open Access Journals (Sweden)

    Z. Xie

    2013-01-01

    Full Text Available The basic principles and methods for a functional glacier systems model are introduced and applied for glaciers of Northwest China. When running the model we assume that a glacier system is under steady state conditions in the initial year. The median size of a glacier system is used as representative for the system. The curve of glacier area distribution against elevation is used to compute the increase in equilibrium line altitude (ELA, and the annual glacier ablation is calculated using a global formula a = 1.33(9.66 + ts².⁸⁵ [4, p. 96]. The net mass balance near the ELA under steady state conditions represents the net mass balance of the whole glacier system, and the time required for glacier runoff to return to the initial year level is calculated according to the law of glacier runoff variation, and used to calculate the variation of glacier area. The variation of glacier runoff is modeled according to ablation at the ELA, and the variation of glacier volume is modeled according to the absolute value of the mass balance. The observed changes in surveyed glaciers in China over recent decades were broadly consistent with predictions of the glacier system model. The model therefore offers a reliable method for the prediction of changes in glacier systems in response to changing climate.

  20. 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

  1. Increased Mass Loss and Asynchronous Behavior of Marine-Terminating Outlet Glaciers at Upernavik Isstrøm, NW Greenland

    DEFF Research Database (Denmark)

    Larsen, Signe Hillerup; Khan, Shfaqat Abbas; Ahlstrøm, Andreas Peter;

    2016-01-01

    In order to model and predict future behavior of marine terminating glaciers, it is essential to understand the different factors that control a glaciers response to climate change. Here we present a detailed study of the asynchronous changes in dynamic behavior of four adjacent marine-terminatin......In order to model and predict future behavior of marine terminating glaciers, it is essential to understand the different factors that control a glaciers response to climate change. Here we present a detailed study of the asynchronous changes in dynamic behavior of four adjacent marine...... between 1992 and 2013. These observations point out the fact that the UI glaciers are reacting to climate change on different timescales. The asynchronous behavior of the four neighboring glaciers is explained in terms of the individual glaciersâĂŹ geometry and terminus position. The northernmost glacier...

  2. Glacier variations and climate warming and drying in the central Himalayas

    Institute of Scientific and Technical Information of China (English)

    REN Jiawen; QIN Dahe; KANG Shichang; HOU Shugui; PU Jianchen; JING Zhefan

    2004-01-01

    Repeat measurements of glacier terminus positions show that glaciers in the central Himalayas have been in a continuous retreat situation in the past decades. The average retreat rate is 5.5-8.7 m/a in Mt. Qomolangma (Everest) since the 1960s and 6.4 m/a in Mt. Xixiabangma since the 1980s. In recent years, the retreat rate is increasing. Ice core studies revealed that the accumulation rate of glaciers has a fluctuating decrease trend in the last century with a rapid decrease in the 1960s and a relatively steady low value afterwards. Meteorological station record indicates that the annual mean temperature has a slow increase trend but summer temperature had a larger increase in the past 30 a. All these suggest that the glacier retreat results from precipitation decrease in combination with temperature increase, and hence glacier shrinkage in this region will speed up if the climatic warming and drying continues.

  3. Exploring uncertainty in glacier mass balance modelling with Monte Carlo simulation

    NARCIS (Netherlands)

    Machguth, H.; Purves, R.S.; Oerlemans, J.; Hoelzle, M.; Paul, F.

    2008-01-01

    By means of Monte Carlo simulations we calculated uncertainty in modelled cumulative mass balance over 400 days at one particular point on the tongue of Morteratsch Glacier, Switzerland, using a glacier energy balance model of intermediate complexity. Before uncertainty assessment, the model was tun

  4. The equilibrium flow and mass balance of the Taku Glacier, Alaska 1950–2006

    Directory of Open Access Journals (Sweden)

    K. F. Sprenke

    2008-05-01

    Full Text Available The Taku Glacier, Alaska has advanced 7.5 km since the late nineteenth century, while all other primary outlet glaciers of the Juneau Icefield are in retreat. The Juneau Icefield Research Program has completed field work on the Taku Glacier annually since 1946. The collected observations of surface mass balance, glacier velocity and glacier thickness at Profile IV 29 km above the terminus and 4 km above the equilibrium line provide a means to assess the equilibrium nature of the Taku Glacier. Velocity measured over a twelve month span and annual summer velocity measurements completed at a Profile IV from 1950–2006 indicate insignificant variations in velocity seasonally or from year to year. The consistency of velocity over the 56-year period indicates that in the vicinity of the equilibrium line, the flow of the Taku Glacier has been in an equilibrium state. Surface mass balance was positive from 1946–1988 averaging +0.42 m a−1. This led to glacier thickening. From 1988–2006 an important change has occurred and annual balance has been −0.14 m a−1, and the glacier thickness has ceased increasing along Profile IV. Field measurements of ice depth and surface velocity allow calculation of the volume flux at Profile IV. Volume flux is then compared with the surface balance flux from the region of the glacier above Profile IV, determined annually in the field. Above Profile IV the observed mean surface flux is 5.50×108 m3/a (±5%, while the calculated volume flux range flowing through profile IV is 5.00–5.47×108 m3/a. The mean surface flux has been greater than the volume flux, which has led to slow thickening of the Taku Glacier up to 1988. The thickening has not led to a change in the flow of Taku Glacier at Profile IV.

  5. Air temperature variability over three glaciers in the Ortles-Cevedale (Italian Alps): effects of glacier fragmentation, comparison of calculation methods, and impacts on mass balance modeling

    Science.gov (United States)

    Carturan, L.; Cazorzi, F.; De Blasi, F.; Dalla Fontana, G.

    2015-05-01

    Glacier mass balance models rely on accurate spatial calculation of input data, in particular air temperature. Lower temperatures (the so-called glacier cooling effect) and lower temperature variability (the so-called glacier damping effect) generally occur over glaciers compared to ambient conditions. These effects, which depend on the geometric characteristics of glaciers and display a high spatial and temporal variability, have been mostly investigated on medium to large glaciers so far, while observations on smaller ice bodies (< 0.5 km2) are scarce. Using a data set from eight on-glacier and four off-glacier weather stations, collected in the summers of 2010 and 2011, we analyzed the air temperature variability and wind regime over three different glaciers in the Ortles-Cevedale. The magnitude of the cooling effect and the occurrence of katabatic boundary layer (KBL) processes showed remarkable differences among the three ice bodies, suggesting the likely existence of important reinforcing mechanisms during glacier decay and fragmentation. The methods proposed by Greuell and Bohm (1998) and Shea and Moore (2010) for calculating on-glacier temperature from off-glacier data did not fully reproduce our observations. Among them, the more physically based procedure of Greuell and Bohm (1998) provided the best overall results where the KBL prevails, but it was not effective elsewhere (i.e., on smaller ice bodies and close to the glacier margins). The accuracy of air temperature estimations strongly impacted the results from a mass balance model which was applied to the three investigated glaciers. Most importantly, even small temperature deviations caused distortions in parameter calibration, thus compromising the model generalizability.

  6. Simulation of historic glacier variations with a simple climate-glacier model

    NARCIS (Netherlands)

    Oerlemans, J.

    1988-01-01

    Glacier variations during the last few centuries have shown a marked coherence over the globe. Characteristic features are the maximum stand somewhere in the middle of the nineteenth century, and the steady retreat afterwards (with some minor interrruptions depending on the particular region). In ma

  7. Mass Change of Glaciers in Muztag Ata-Kongur Tagh, Eastern Pamir, China from 1971/76 to 2013/14 as Derived from Remote Sensing Data.

    Science.gov (United States)

    Zhang, Zhen; Liu, Shiyin; Wei, Junfeng; Xu, Junli; Guo, Wanqin; Bao, Weijia; Jiang, Zongli

    2016-01-01

    The assessment of glacier mass budget is crucial for assessing water reserves stored in glaciers. Derived glacier mass changes in the Muztag Ata and Kongur Tagh (MAKT) region in the eastern Pamir, northwestern China, is helpful in improving our knowledge of the dynamics of glaciers under a changing climate in High Mountain Asia. Here, glacier area and mass changes derived from remote sensing data are investigated for the period 1971/76-2013/14 for glaciers in MAKT. We have used ASTER images (2013/14), Cartosat-1 (2014) and Landsat, SRTM (Shuttle Radar Terrain Mission) digital elevation model (DEM) (2000), topographic maps (1971/76) and the first and second Chinese glacier inventories (CGIs). Our results indicated that the glacier area of MAKT decreased from 1018.3 ± 12.99 km(2) in 1971/76 to 999.2 ± 31.22 km(2) in 2014 (-1.9 ± 0.2%). Weak area shrinkage of glaciers by 2.5 ± 0.5 km(2) (0.2 ± 0.1%) happened after 2000 and the period 2009-2014 even saw a slight expansion by 0.5 ± 0.1 km(2) (0.1 ± 0.0%). The glaciers in this region have experienced an overall loss of -6.99 ± 0.80 km(3) in ice volume or -0.15 ± 0.12 m water equivalent (w.e.) a-1 from 1971/76 to 2013/14. The mass budget of MAKT was -0.19 ± 0.19 m w.e. a-1 for the period ~1971/76-1999 and -0.14 ± 0.24 m w.e. a-1 during 1999-2013/2014. Similar to previous studies, there has been little mass change in the Pamir over recent decades despite such uncertainties. Glacier mass change showed spatial and temporal heterogeneity, with strong mass loss on debris-covered glaciers with an average of -0.32 ± 0.12 m w.e. a-1 from the 1970s to 2013/14. PMID:26789404

  8. Mass Change of Glaciers in Muztag Ata-Kongur Tagh, Eastern Pamir, China from 1971/76 to 2013/14 as Derived from Remote Sensing Data.

    Directory of Open Access Journals (Sweden)

    Zhen Zhang

    Full Text Available The assessment of glacier mass budget is crucial for assessing water reserves stored in glaciers. Derived glacier mass changes in the Muztag Ata and Kongur Tagh (MAKT region in the eastern Pamir, northwestern China, is helpful in improving our knowledge of the dynamics of glaciers under a changing climate in High Mountain Asia. Here, glacier area and mass changes derived from remote sensing data are investigated for the period 1971/76-2013/14 for glaciers in MAKT. We have used ASTER images (2013/14, Cartosat-1 (2014 and Landsat, SRTM (Shuttle Radar Terrain Mission digital elevation model (DEM (2000, topographic maps (1971/76 and the first and second Chinese glacier inventories (CGIs. Our results indicated that the glacier area of MAKT decreased from 1018.3 ± 12.99 km(2 in 1971/76 to 999.2 ± 31.22 km(2 in 2014 (-1.9 ± 0.2%. Weak area shrinkage of glaciers by 2.5 ± 0.5 km(2 (0.2 ± 0.1% happened after 2000 and the period 2009-2014 even saw a slight expansion by 0.5 ± 0.1 km(2 (0.1 ± 0.0%. The glaciers in this region have experienced an overall loss of -6.99 ± 0.80 km(3 in ice volume or -0.15 ± 0.12 m water equivalent (w.e. a-1 from 1971/76 to 2013/14. The mass budget of MAKT was -0.19 ± 0.19 m w.e. a-1 for the period ~1971/76-1999 and -0.14 ± 0.24 m w.e. a-1 during 1999-2013/2014. Similar to previous studies, there has been little mass change in the Pamir over recent decades despite such uncertainties. Glacier mass change showed spatial and temporal heterogeneity, with strong mass loss on debris-covered glaciers with an average of -0.32 ± 0.12 m w.e. a-1 from the 1970s to 2013/14.

  9. Mass Change of Glaciers in Muztag Ata-Kongur Tagh, Eastern Pamir, China from 1971/76 to 2013/14 as Derived from Remote Sensing Data.

    Science.gov (United States)

    Zhang, Zhen; Liu, Shiyin; Wei, Junfeng; Xu, Junli; Guo, Wanqin; Bao, Weijia; Jiang, Zongli

    2016-01-01

    The assessment of glacier mass budget is crucial for assessing water reserves stored in glaciers. Derived glacier mass changes in the Muztag Ata and Kongur Tagh (MAKT) region in the eastern Pamir, northwestern China, is helpful in improving our knowledge of the dynamics of glaciers under a changing climate in High Mountain Asia. Here, glacier area and mass changes derived from remote sensing data are investigated for the period 1971/76-2013/14 for glaciers in MAKT. We have used ASTER images (2013/14), Cartosat-1 (2014) and Landsat, SRTM (Shuttle Radar Terrain Mission) digital elevation model (DEM) (2000), topographic maps (1971/76) and the first and second Chinese glacier inventories (CGIs). Our results indicated that the glacier area of MAKT decreased from 1018.3 ± 12.99 km(2) in 1971/76 to 999.2 ± 31.22 km(2) in 2014 (-1.9 ± 0.2%). Weak area shrinkage of glaciers by 2.5 ± 0.5 km(2) (0.2 ± 0.1%) happened after 2000 and the period 2009-2014 even saw a slight expansion by 0.5 ± 0.1 km(2) (0.1 ± 0.0%). The glaciers in this region have experienced an overall loss of -6.99 ± 0.80 km(3) in ice volume or -0.15 ± 0.12 m water equivalent (w.e.) a-1 from 1971/76 to 2013/14. The mass budget of MAKT was -0.19 ± 0.19 m w.e. a-1 for the period ~1971/76-1999 and -0.14 ± 0.24 m w.e. a-1 during 1999-2013/2014. Similar to previous studies, there has been little mass change in the Pamir over recent decades despite such uncertainties. Glacier mass change showed spatial and temporal heterogeneity, with strong mass loss on debris-covered glaciers with an average of -0.32 ± 0.12 m w.e. a-1 from the 1970s to 2013/14.

  10. Glacier mass balance in high-arctic areas with anomalous gravity

    Science.gov (United States)

    Sharov, A.; Rieser, D.; Nikolskiy, D.

    2012-04-01

    All known glaciological models describing the evolution of Arctic land- and sea-ice masses in changing climate treat the Earth's gravity as horizontally constant, but it isn't. In the High Arctic, the strength of the gravitational field varies considerably across even short distances under the influence of a density gradient, and the magnitude of free air gravity anomalies attains 100 mGal and more. On long-term base, instantaneous deviations of gravity can have a noticeable effect on the regime and mass budget of glaciological objects. At best, the gravity-induced component of ice mass variations can be determined on topographically smooth, open and steady surfaces, like those of arctic planes, regular ice caps and landfast sea ice. The present research is devoted to studying gravity-driven impacts on glacier mass balance in the outer periphery of four Eurasian shelf seas with a very cold, dry climate and rather episodic character of winter precipitation. As main study objects we had chosen a dozen Russia's northernmost insular ice caps, tens to hundreds of square kilometres in extent, situated in a close vicinity of strong gravity anomalies and surrounded with extensive fields of fast and/or drift ice for most of the year. The supposition about gravitational forcing on glacioclimatic settings in the study region is based on the results of quantitative comparison and joint interpretation of existing glacier change maps and available data on the Arctic gravity field and solid precipitation. The overall mapping of medium-term (from decadal to half-centennial) changes in glacier volumes and quantification of mass balance characteristics in the study region was performed by comparing reference elevation models of study glaciers derived from Russian topographic maps 1:200,000 (CI = 20 or 40 m) representing the glacier state as in the 1950s-1980s with modern elevation data obtained from satellite radar interferometry and lidar altimetry. Free-air gravity anomalies were

  11. Influence of high-order mechanics on simulation of glacier response to climate change: insights from Haig Glacier, Canadian Rocky Mountains

    Directory of Open Access Journals (Sweden)

    S. Adhikari

    2013-04-01

    Full Text Available Evolution of glaciers in response to climate change has mostly been simulated using simplified dynamical models. Because these models do not account for the influence of high-order physics, corresponding results may exhibit some biases. For Haig Glacier in the Canadian Rocky Mountains, we test this hypothesis by comparing simulation results obtained from 3-D numerical models that deal with different assumptions concerning ice-flow physics, ranging from simple shear-deformation to comprehensive Stokes flow. In glacier retreat scenarios, we find a minimal role of high-order mechanics in glacier evolution, as geometric effects at our site (the presence of an overdeepened bed result in limited horizontal movement of ice (flow speed on the order of a few meters per year. Consequently, high-order and reduced models all predict that Haig Glacier ceases to exist by ca. 2080 under ongoing climate warming. The influence of high-order mechanics is evident, however, in glacier advance scenarios, where ice speeds are greater and ice dynamical effects become more important. To generalize these findings for other glacier applications, we advise that high-order mechanics are important and therefore should be considered while modelling the evolution of active glaciers. Reduced model predictions may, however, be adequate for other glaciologic and topographic settings, particularly where flow speeds are low.

  12. Processes governing the mass balance of Chhota Shigri Glacier (Western Himalaya, India assessed by point-scale surface energy balance measurements

    Directory of Open Access Journals (Sweden)

    M. F. Azam

    2014-06-01

    Full Text Available Recent studies revealed that Himalayan glaciers have been shrinking at an accelerated rate since the beginning of the 21st century. However the climatic causes for this shrinkage remain unclear given that surface energy balance studies are almost nonexistent in this region. In this study, a point-scale surface energy balance analysis was performed using in-situ meteorological data from the ablation zone of Chhota Shigri Glacier over two separate periods (August 2012 to February 2013 and July to October 2013 in order to understand the response of mass balance to climate change. Energy balance numerical modeling provides quantification of the surface energy fluxes and identification of the factors affecting glacier mass balance. The computed ablation was validated by stake observations. During summer-monsoon period, net radiation was the primary component of the surface energy balance with 82% of the total heat flux which was complimented with turbulent sensible and latent heat fluxes with a share of 13% and 5%, respectively. A striking feature of energy balance is the positive turbulent latent heat flux, thus condensation or re-sublimation of moist air at the glacier surface takes place, during summer-monsoon period which is characterized by relatively high air temperature, high relative humidity and almost permanent melting surface. The impact of Indian summer monsoon on Chhota Shigri Glacier mass balance has also been assessed. This analysis demonstrates that the intensity of snowfall events during the summer-monsoon season plays a key role on surface albedo, in turn on melting, and thus is among the most important drivers controlling the annual mass balance of the glacier. Summer-monsoon air temperature, controlling the precipitation phase (rain vs. snow and thus albedo, counts, indirectly, also among the most important drivers for the glacier mass balance.

  13. Quantifying the mass loss of peripheral Greenland glaciers and ice caps (1958-2014).

    Science.gov (United States)

    Noël, Brice; van de Berg, Willem Jan; Machguth, Horst; van den Broeke, Michiel

    2016-04-01

    Since the 2000s, mass loss from Greenland peripheral glaciers and ice caps (GICs) has accelerated, becoming an important contributor to sea level rise. Under continued warming throughout the 21st century, GICs might yield up to 7.5 to 11 mm sea level rise, with increasing dominance of surface runoff at the expense of ice discharge. However, despite multiple observation campaigns, little remains known about the contribution of GICs to total Greenland mass loss. Furthermore, the relatively coarse resolutions in regional climate models, i.e. 5 km to 20 km, fail to represent the small scale patterns of surface mass balance (SMB) components over these topographically complex regions including also narrow valley glaciers. Here, we present a novel approach to quantify the contribution of GICs to surface melt and runoff, based on an elevation dependent downscaling method. GICs daily SMB components at 1 km resolution are obtained by statistically downscaling the outputs of RACMO2.3 at 11 km resolution to a down-sampled version of the GIMP DEM for the period 1958-2014. This method has recently been successfully validated over the Greenland ice sheet and is now applied to GICs. In this study, we first evaluate the 1 km daily downscaled GICs SMB against a newly available and comprehensive dataset of ablation stake measurements. Then, we investigate present-day trends of meltwater production and SMB for different regions and estimate GICs contribution to total Greenland mass loss. These data are considered valuable for model evaluation and prediction of future sea level rise.

  14. Adapting to the reality of climate change at Glacier National Park, Montana, USA

    Science.gov (United States)

    Fagre, Daniel B.

    2007-01-01

    The glaciers of Glacier National Park (GNP) are disappearing rapidly and likely will be gone by 2030. These alpine glaciers have been continuously present for approximately 7,000 years so their loss from GNP in another 25 years underscores the significance of current climate change. There are presently only 27 glaciers remaining of the 150 estimated to have existed when GNP was created in 1910. Mean annual temperature in GNP has increased 1.6 0 C during the past cen- tury, three times the global mean increase. The temperature increase has affected other parts of the mountain ecosystem, too. Snowpacks hold less water equivalent and melt 2+ weeks earlier in the spring. Forest growth rates have increased, alpine treelines have expanded upward and be- come denser, and subalpine meadows have been invaded by high elevation tree species. These latter responses can be mostly attributed to longer growing seasons and warmer temperatures.

  15. Mass loss of Greenland's glaciers and ice caps 2003-2008 revealed from ICESat laser altimetry data

    OpenAIRE

    T. Bolch; L. Sandberg Sørensen; Simonsen, S.B.; Mölg, N.; Machguth, H.; Rastner, P.; Paul, F.

    2013-01-01

    The recently finalized inventory of Greenland's glaciers and ice caps (GIC) allows for the first time to determine the mass changes of the GIC separately from the ice sheet using space-borne laser altimetry data. Corrections for firn compaction and density that are based on climatic conditions are applied for the conversion from volume to mass changes. The GIC which are clearly separable from the icesheet (i.e., have a distinct ice divide or no connection) lost 27.9 ± 10.7 Gt a-1 or 0.08 ± 0....

  16. Cloud effects on surface energy and mass balance in the ablation area of Brewster Glacier, New Zealand

    Science.gov (United States)

    Conway, J. P.; Cullen, N. J.

    2016-02-01

    The effect of clouds on glacier surface energy balance (SEB) has received increased attention in the last decade, but how clouds interact with other meteorological forcing to influence surface mass balance (SMB) is not as well understood. This paper resolves the SEB and SMB at a site in the ablation zone of Brewster Glacier over a 22-month period, using high-quality radiation data to carefully evaluate SEB terms and define clear-sky and overcast conditions. A fundamental change in glacier SEB in cloudy conditions was driven by increased effective sky emissivity and surface vapour pressure, rather than a minimal change in air temperature and wind speed. During overcast conditions, positive net long-wave radiation and latent heat fluxes allowed melt to be maintained through a much greater length of time compared to clear-sky conditions, and led to similar melt in each sky condition. The sensitivity of SMB to changes in air temperature was greatly enhanced in overcast compared to clear-sky conditions due to more frequent melt and changes in precipitation phase that created a strong albedo feedback. During the spring and autumn seasons, the sensitivity during overcast conditions was strongest. To capture these processes, future attempts to explore glacier-climate interactions should aim to resolve the effects of atmospheric moisture (vapour, cloud, and precipitation) on melt as well as accumulation, through enhanced statistical or physically based methods.

  17. Mass balance evolution of Martial Este Glacier, Tierra del Fuego (Argentina for the period 1960–2099

    Directory of Open Access Journals (Sweden)

    M. Buttstädt

    2009-12-01

    Full Text Available The Martial Este Glacier in southern Tierra del Fuego was studied in order to estimate the surface mass balance from 1960 until 2099. For this reason a degree-day model was calibrated. Air temperature and precipitation data obtained from 3 weather stations as well as glaciological measurements were applied. The model was driven using a vertical air temperature gradient of 0.69 K/100 m, a degree-day factor for snow of 4.7 mm w.e. K−1 day−1, a degree-day factor for ice of 9.4 mm w.e. K−1 day−1 and a precipitation gradient of 22%/100 m. For the purpose of surface mass balance reconstruction for the time period 1960 until 2006 a winter vertical air temperature gradient of 0.57 K/100 m and a summer vertical air temperature gradient of 0.71 K/100 m were added as well as a digital terrain model. The key finding is an almost continuous negative mass balance of −772 mm w.e. a−1 throughout this period. While the calculation of the mass balance for the period 1960–2006 is based on instrumental records, the mass balance for the years 2007 until 2099 was estimated based on the IPCC SRES A2-scenario. To accomplish this estimation, the dataset of the global climate model HadCM3 was statistically downscaled to fit local conditions at Martial Este Glacier. Subsequently, the downscaled air temperature and precipitation were applied to a volume-area scaling glacier change model. Findings reveal an enduring deglaciation resulting in a surface area reduction of nearly 93% until 2099. This implicates that the Martial Este Glacier might be melted off at the beginning of the 22nd century.

  18. Regional estimates of glacier mass change from MODIS-derived equilibrium line altitudes

    Directory of Open Access Journals (Sweden)

    J. M. Shea

    2012-09-01

    Full Text Available We describe an automated method to extract regional snowline elevations and annual equilibrium line altitudes (ELAs from daily MODIS imagery (MOD02QKM on large glaciers and icefields in western North America. Regional MODIS-derived ELAs correlate significantly with observed net mass balance at six index glacier mass balance sites. Historical mass balance gradients were combined with MODIS-derived ELAs to estimate annual mass change at the Columbia, Lillooet, and Sittakanay icefields in British Columbia, Canada. Our approach yields estimates of mass change that are within 30% of traditional geodetic approaches over decadal time-scales, and reveals continued mass loss of glaciers in western North America. Between 2000 and 2009, mean annual rates of surface elevation change for the Columbia, Lillooet, and Sittakanay icefields are estimated to be −0.29 ± 0.15 m a−1, −0.57 ± 0.10 m a−1, and −0.90 ± 0.09 m a−1, respectively. This study provides a complementary approach to the development of regional estimates of glacier mass change, which are critical for studies of glacier contributions to both streamflow and global sea-level rise.

  19. Mass losses from Svalbard land-terminating glaciers by the end of the 21st century under an RCP 8.5 scenario

    Science.gov (United States)

    Möller, Marco; Navarro, Francisco; Martín-Español, Alba

    2016-04-01

    The high Arctic archipelagos are among the most strongly glacierized landscapes on earth apart from the Greenland and Antarctic ice sheets. Svalbard, one of these archipelagos, holds about 36,000 km2 of glaciers and ice caps and is the region that has shown the least negative mass balance of all the high Arctic regions. However, future projections suggest that the archipelago will experience an unprecedented -for the Arctic- glacier recession over the 21st century. We here present a high-resolution modelling study of the future ice-mass evolution of 29 individual land-terminating glaciers on the Svalbard archipelago under an RCP 8.5 climate forcing, a rather pessimistic scenario that unfortunately seems to be becoming realistic. Our model calculates glacier mass balance and area/volume changes using a temperature-index approach in combination with a surface elevation change parameterization. The initial glacier topographies and volumes have been assessed from extensive ground-penetrating radar measurements carried out in recent years. The calculations are performed for the 21st century and are forced by statistically downscaled output of ten different global circulation models representing the RCP scenario 8.5. By a topography-based extrapolation of the simulation results to the entire archipelago we show that a complete loss of most of Svalbard's land-terminating glaciers and even a deglaciation of certain subregions of the archipelago might occur by the end of the 21st century. 98% of the land-terminating glaciers will have retreated to less than one tenth of their initial extent by 2100, resulting in a loss of 7392±2481 km2 of ice coverage.

  20. Response of Glacier and Lake Covariations to Climate Change in Mapam Yumco Basin on Tibetan Plateau during 1974-2003

    Institute of Scientific and Technical Information of China (English)

    Ye Qinghua; Yao Tandong; Chen Feng; Kang Shichang; Zhang Xueqin; Wang Yi

    2008-01-01

    The study of spatial and temporal covariances of glaciers and lakes would help us to understand the impact of climate change within a basin in Tibet. This study focuses on glacier and lake variations in the Mapam Yumco(玛旁雍错)Basin (covering 7 786.44 km2)by Integrationg series of spatial data from topographic maps and digital satellite images at four different times: 1974, 1990, 1999,and 2003. The results indicate that: (1) decreased lakes, retreated glaciers, enlarged lakes and advanced glaciers co-exist in the basin during the last 30 years; (2) glacier recession was accelerated in recent years due to the warmer climate; (3) lake areas in the basin are both reduced and enlarged by an accelerated speed with more water supplies from speeding melt glaciers or frozen ground in the last three decades.

  1. Climate Sensitivity of Franz-Josef Glacier, New Zealand, as revealed by numerical modelling

    NARCIS (Netherlands)

    Oerlemans, J.

    1997-01-01

    The sensitivity of Franz Josef Glacier is studied with a numerical ice-flow model. The model calculates ice mass flux along a central flow line and deals with the three-dimensional geometry in a parameterized way. Forcing is provided through a mass balance model that generates specific balance from

  2. Climate change and glacier retreat in northern Tien Shan (Kazakhstan/Kyrgyzstan) using remote sensing data

    Science.gov (United States)

    Bolch, Tobias

    2007-03-01

    This paper presents an analysis of precipitation and temperature trends and a GIS-supported investigation of the related glacier change in the mountain ridges Zailiyskiy and Kungey Alatau, which represent an important part of the northern Tien Shan. The recent glacier coverage was delineated in a semi-automated way using a TM4/TM5 ratio image of a Landsat ETM Scene from the year 1999 and a merged ASTER/SRTM3-DEM. The extent of these glaciers is compared to that of the glaciers in the Soviet Glacier Inventory [UdSSR, Academica Nauk (1966 to 1983). Katalog Lednikov SSSR (in Russian), Gidrometeoizdat. Leningrad], which represents the situation in study area in approx. 1955. Regionalization of temperature and precipitation as well as solar radiation calculation was conducted in order to determine the climate situation at the glaciers. Trend and correlation analysis for the period from 1879 to 2000 at 16 climate stations showed a temperature increase, which have become pronounced since the 1950s. Another strong increase occurred at the beginning of the 1970s and since around 1980, the temperatures have generally stayed at this high level. The trend coefficient was about 0.8 K/100a for the period 1900 to 2000 and about 2.0 K/100a on average for the second half of the last century. The increase was about two times higher than the global average in northern Tien Shan from 1950 until 2000, where the increase was mainly due to temperature rise in autumn and winter. The increase is less pronounced in the mountainous areas, but still obvious. However, the higher temperature increase at the lower stations, located for the most part in cities or larger settlements, may be due in part to increased urbanization. For precipitation, there was a small increase on average, but no clear trend. On the average, the decrease in glacier extent was more than 32% between 1955 and 1999 in the investigated valleys of Zailiyskiy and Kungey Alatau. The glacier retreat was not homogeneous, but

  3. Glacier mass change projections and commitments resulting from the Paris Agreement

    Science.gov (United States)

    Marzeion, Ben; Kaser, Georg; Maussion, Fabien

    2016-04-01

    At COP21, the UNFCCC agreed to hold "the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels". Using an ensemble of global glacier model integrations, we estimate the glacier mass change commitment and its temporal evolution resulting from a hypothesized success of the Paris Agreement. Our preliminary results indicate that under 1.5°C global mean temperature increase, glaciers will eventually lose mass corresponding to 133 mm SLE (90 % confidence interval: 83 to 154 mm SLE), compared to 164 mm SLE (110 to 184 mm SLE) under 2.0°C warming. In order to stabilize glaciers at their current global mass, a temperature of 0.17°C (-0.13 to 0.43°C) above pre-industrial would be required. Only a fraction of the long-term mass loss would be realized within the 21st century. Based on scaling existing GCM integrations under the RCP2.6 scenario to 1.5°C global warming, 21st century mass loss of glaciers would correspond to 84 mm SLE (64 to 110 mm SLE). Under the original RCP2.6 scenario, this number climbs to 100 mm SLE (67 to 137 mm SLE).

  4. Fast shrinkage of tropical glaciers in Colombia

    Science.gov (United States)

    Ceballos, Jorge Luis; Euscátegui, Christian; Ramírez, Jair; Cañon, Marcela; Huggel, Christian; Haeberli, Wilfried; Machguth, Horst

    As a consequence of ongoing atmospheric temperature rise, tropical glaciers belong to the unique and threatened ecosystems on Earth, as defined by the Intergovernmental Panel on Climate Change (Houghton and others, 2001). Worldwide glacier monitoring, especially as part of the Global Climate Observing System (GCOS), includes the systematic collection of data on such perennial surface ice masses. Several peaks in the sierras of Colombia have lost their glacier cover during recent decades. Today, high-altitude glaciers still exist in Sierra Nevada de Santa Marta, in Sierra Nevada del Cocuy and on the volcanoes of Nevados del Ruiz, de Santa Isabel, del Tolima and del Huila. Comparison of reconstructions of maximum glacier area extent during the Little Ice Age with more recent information from aerial photographs and satellite images clearly documents a fast-shrinking tendency and potential disappearance of the remaining glaciers within the next few decades. In the past 50 years, Colombian glaciers have lost 50% or more of their area. Glacier shrinkage has continued to be strong in the last 15 years, with a loss of 10-50% of the glacier area. The relationship between fast glacier retreat and local, regional and global climate change is now being investigated. Preliminary analyses indicate that the temperature rise of roughly 1° C in the last 30 years recorded at high-altitude meteorological stations exerts a primary control on glacier retreat. The investigations on the Colombian glaciers thus corroborate earlier findings concerning the high sensitivity of glaciers in the wet inner tropics to temperature rise. To improve understanding of fast glacier retreat in Colombia, a modern monitoring network has been established according to the multilevel strategy of the Global Terrestrial Network for Glaciers (GTN-G) within GCOS. The observations are also contributions to continued assessments of hazards from the glacier-covered volcanoes and to integrated global change

  5. Spatial patterns of North Atlantic Oscillation influence on mass balance variability of European glaciers

    Directory of Open Access Journals (Sweden)

    B. Marzeion

    2012-06-01

    Full Text Available We present and validate a set of minimal models of glacier mass balance variability. The most skillful model is then applied to reconstruct 7735 individual time series of mass balance variability for all glaciers in the European Alps and Scandinavia. Subsequently, we investigate the influence of atmospheric variability associated with the North Atlantic Oscillation (NAO on the glaciers' mass balances.

    We find a spatial coherence in the glaciers' sensitivity to NAO forcing which is caused by regionally similar mechanisms relating the NAO forcing to the mass balance: in southwestern Scandinavia, winter precipitation causes a correlation of mass balances with the NAO. In northern Scandinavia, temperature anomalies outside the core winter season cause an anti-correlation between NAO and mass balances. In the western Alps, both temperature and winter precipitation anomalies lead to a weak anti-correlation of mass balances with the NAO, while in the eastern Alps, the influences of winter precipitation and temperature anomalies tend to cancel each other, and only on the southern side a slight anti-correlation of mass balances with the NAO prevails.

  6. Little Ice Age glaciers in Britain: Glacier–climate modelling in the Cairngorm Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Stephan Harrison; Ann V. Rowan; Neil F. Glasser; Jasper Knight; Mitchell A. Plummer; Stephanie C. Mills

    2014-02-01

    It is widely believed that the last glaciers in the British Isles disappeared at the end of the Younger Dryas stadial (12.9–11.7 cal. kyr BP). Here, we use a glacier–climate model driven by data from local weather stations to show for the first time that glaciers developed during the Little Ice Age (LIA) in the Cairngorm Mountains. Our model is forced from contemporary conditions by a realistic difference in mean annual air temperature of -1.5 degrees C and an increase in annual precipitation of 10%, and confirmed by sensitivity analyses. These results are supported by the presence of small boulder moraines well within Younger Dryas ice limits, and by a dating programme on a moraine in one cirque. As a result, we argue that the last glaciers in the Cairngorm Mountains (and perhaps elsewhere in upland Britain) existed in the LIA within the last few hundred years, rather than during the Younger Dryas.

  7. Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming - Taking Xinjiang Glaciated Region as Example

    Institute of Scientific and Technical Information of China (English)

    WANG Xin; XIE Zichu; LIU Shiyin; TAO Jianjun; HAN Yongshun; YANG Yuelong

    2005-01-01

    The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions.On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state (ELAo), a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation.The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03 and 0.05 K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change: if temperature become 1℃ higher, the precipitation would be increased by 10%, which can slow down the glaciers retreating rate in the area by 4%, accelerate runoff increasing rate by 8% and depress the ELAo rising gradient by 24 m in northern Xinjiang glacier system where semi-continental glaciers dominate,while it has corresponding values of only 1%, 5 % and 18m respectively in southern Xinjiang glacier system,where extremely continental glaciers dominate.

  8. Assessing streamflow sensitivity to variations in glacier mass balance

    Science.gov (United States)

    O'Neel, Shad; Hood, Eran; Arendt, Anthony; Sass, Louis

    2014-01-01

    The mountains ringing the Gulf of Alaska (GOA) receive upwards of 4–8 m yr−1 of precipitation (Simpson et al.2005; Weingartner et al. 2005; O’Neel 2012), much of which runs off into productive coastal waters. The alpine landscape is heavily glacierized, and storage and turnover of water by glaciers substantially influences the regional surface water balance (Neal et al. 2010). In turn, the land-to-ocean flux of freshwater impacts the biogeochemistry, physical oceanography, freshwater and marine ecology of the downstream components of the GOA ecosystem (e.g., Royer et al. 2001; Hood and Scott 2008). In this way, the links between terrestrial and ocean ecosystems along the GOA have widespread impacts on regional socioeconomic issues including water and hydropower resources, fish populations, and sea level change (Dorava and Milner 2000; Royer and Grosch 2006; Cherry et al. 2010; Gardner et al. 2013). Moreover, predicting future changes in physical, chemical and biological processes in near-shore ecosystems along the GOA hinges, in part, on developing a robust understanding of water storage and transfer by glaciers through streams to the ocean.

  9. Climate Change, Glaciers, and Water Management in the Rio Santa Watershed, Peru

    Science.gov (United States)

    Purkey, D. R.; Escobar, M.

    2009-12-01

    Recent decades have witnessed the dramatic decline in the spatial extent of tropical glaciers in the Andes Mountains. In the Rio Santa watershed of Peru, which lies on the western slope of the Cordillera Blanca, the glaciated area has declined from 507 km2 in 1970 to 387 km2 in 1999. The continual evolution of seasonal patterns of glacier accumulation and ablation have been held up as early sign of the impacts of global climate change on terrestrial hydrology. For water managers in the Andes, the cause of the recent glacier retreat is of less importance than the profound implications continued retreat will have on future hydrologic regimes in systems that are managed to meet multiple objectives, including domestic water supplies, irrigation and hydropower production, which provides over 70% of electricity demands in Peru. This research describes our efforts introduce a glacier evolution module, based on a degree-time formulation, into a water resources systems simulation tool. The Water Evaluation and Planning (WEAP) system, developed by the Stockholm Environment Institute, includes a dynamic integration of routines to simulate the terrestrial components of the hydrologic cycle and routines to allocate available water supplies to meet water demands. With the addition of a glacier routine, WEAP was applied to the Rio Santa and used to evaluate potential climate change impacts on glacier evolution and hydropower production in this important Peruvian watershed over 30 and 100 year planning horizons. Under a dry scenario glaciated areas in the Cordillera Blanca decreases by an additional 47% up to 2036, posing contraints on hydropower production during low flow periods.

  10. A comparison of different methods of evaluating glacier response characteristics: application to glacier AX010, Nepal Himalaya

    Directory of Open Access Journals (Sweden)

    S. Adhikari

    2009-09-01

    Full Text Available Himalayan glaciers are considered to be amongst the most sensitive glaciers to climate change. However, the response behaviour of these glaciers is not well understood. Here we use several approaches to estimate characteristic timescales of glacier AX010, a small valley glacier in the Nepal Himalaya, as a measure of glacier sensitivity. Assuming that temperature solely defines the mass budget, glacier AX010 waits for about 8 yr (reaction time to exhibit its initial terminus response to changing climate. On the other hand, it takes between 29–56 yr (volume response time and 37–70 yr (length response time to adjust its volume and length following the changes in mass balance conditions, respectively. A numerical ice-flow model, the only method that yields both length and volume response time, confirms that a glacier takes longer to adjust its length than its volume.

  11. A model study of Abrahamsenbreen, a surging glacier in northern Spitsbergen

    NARCIS (Netherlands)

    Oerlemans, J.; van Pelt, W. J. J.

    2015-01-01

    The climate sensitivity of Abrahamsenbreen, a 20 km long surge-type glacier in northern Spitsbergen, is studied with a simple glacier model. A scheme to describe the surges is included, which makes it possible to account for the effect of surges on the total mass budget of the glacier. A climate rec

  12. Early 21st-Century Mass loss of the North-Atlantic Glaciers and Ice Caps (Arne Richter Award for Outstanding Young Scientists Lecture)

    Science.gov (United States)

    Wouters, Bert; Ligtenberg, Stefan; Moholdt, Geir; Gardner, Alex S.; Noel, Brice; Kuipers Munneke, Peter; van den Broeke, Michiel; Bamber, Jonathan L.

    2016-04-01

    Historically, ice loss from mountain glaciers and ice caps has been one of the largest contributors to sea level rise over the last century. Of particular interest are the glaciers and ice caps in the North-Atlantic region of the Arctic. Despite the cold climate in this area, considerable melting and runoff occurs in summer. A small increase in temperature will have an immediate effect on these processes, so that a large change in the Arctic ice volume can be expected in response to the anticipated climate change in the coming century. Unfortunately, direct observations of glaciers are sparse and are biased toward glaciers systems in accessible, mostly maritime, climate conditions. Remote sensing is therefore essential to monitor the state of the the North-Atlantic glaciers and ice caps. In this presentation, we will discuss the progress that has been made in estimating the ice mass balance of these regions, with a particular focus on measurements made by ESA's Cryosat-2 radar altimeter mission (2010-present). Compared to earlier altimeter mission, Cryosat-2 provides unprecedented coverage of the cryosphere, with a resolution down to 1 km or better and sampling at monthly intervals. Combining the Cryosat-2 measurements with the laser altimetry data from ICESat (2003-2009) gives us a 12 yr time series of glacial mass loss in the North Atlantic. We find excellent agreement between the altimetry measurements and independent observations by the GRACE mission, which directly 'weighs' the ice caps, albeit at a much lower resolution. Mass loss in the region has increased from 120 Gigatonnes per year in 2003-2009 to roughly 140 Gt/yr in 2010-2014, with an important contribution from Greenland's peripheral glaciers and ice caps. Importantly, the mass loss is not stationary, but shows large regional interannual variability, with mass loss shifting between eastern and western regions from year to year. Comparison with regional climate models shows that these shifts can be

  13. Reconstruction of mass balance of Nevado Coropuna glaciers (Southern Peru) for Late Pleistocene, Little Ice Age and the present.

    Science.gov (United States)

    Ubeda, J.; Palacios, D.

    2009-04-01

    The Nevado Coropuna volcanic complex (15th 31'S-72 ° 39 ° W) is the quaternary stratovolcano northernmost of the central volcanic zone (CVZ) in the western flank of the Central Andes (Southern Peru). This consists in four adjacent volcanic buildings that are occupied over 5.100-5.700 masl by a system of glaciers covering an area of 47 Km2 in 2007 (Ubeda et al, 2008). The maximum expansion of glaciers during the Pleistocene affected an area of ~449 Km2, dropping to altitudes around 3.600-4800 m (Ubeda et al, 2007). In this work were mapped several hundreds of moraines which constitute a record of climate change since the last glacial maximum (LGM). Current glacier system is formed by dozen of glaciers descending slope down in all directions. Coropuna complex is an excellent laboratory for to investigate the control that climate change, tectonics and volcanism exert on the dynamics of glaciers, a scale of tens of years (by studying current glaciers) and also of tens of thousands of years (by analyzing the geomorphological evidence of its evolution in the past). Ubeda et al. (2008) analyzed the evolution of eighteen glaciers of Nevado Coropuna using indicators as surfaces and Equilibrium Line Altitudes (ELAs) of ice masses in 2007, 1986, 1955, Little the Ice Age (LIA) and Last Glacial Maximum (LGM). The glaciers were grouped into two sets: NE group (seven glaciers) and SE group (eleven glaciers). The work included statistical series of ELAs in each phase, estimates by Area x Altitud Balance Ratio (AABR) method, which was proposed by Osmaston (2005), in addition with estimates of timing (~17Cl36 Ka) and magnitude (~ 782-911 m) of ELA depression during LGM. The work included statistical series of ELAs in each phase, estimates by the method Area x Altitud Balance Ratio (AABR) proposed by Osmaston (2005), and in addition estimates of the timing (~17Cl36 Ka) and magnitude (~ 782-911 m) of ELA depression during LGM. The objective of this work is to estimate the current

  14. Long term mass balance of the Helheim and Kangerdlugssuaq glaciers in

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas; Fitzner, Antje; Kjær, Kurt;

    2013-01-01

    Observations over the past decade show huge ice loss associated with speeding up of glaciers in southeast Greenland in 2003, followed by a deceleration in 2006. These short-term episodic dynamic perturbations have a major impact on the mass balance at decadal scale. However, to improve the projec......Observations over the past decade show huge ice loss associated with speeding up of glaciers in southeast Greenland in 2003, followed by a deceleration in 2006. These short-term episodic dynamic perturbations have a major impact on the mass balance at decadal scale. However, to improve...... the projection of future sea level rise, a long-term data record that reveals the mass balance between episodic events is required. Here, we extend the observational record of marginal thinning of Helheim glacier (HG) and Kangerdlugssuaq glacier (KG) from 7 to 30 years. Our measurements reveal that, although...... in air temperature suggest that both outlet glaciers respond immediately to small fluctuations in both the SST and air temperature. Furthermore, we compare our observations of ice flow speed and elevation changes with predictions based on the The Parallel Ice Sheet Model (PISM) software....

  15. The footprint of Asian monsoon dynamics in the mass and energy balance of a Tibetan glacier

    Directory of Open Access Journals (Sweden)

    T. Mölg

    2012-08-01

    Full Text Available Determinations of glacier-wide mass and energy balance are still scarce for the remote mountains of the Tibetan Plateau, where field measurements are challenging. Here we run and evaluate a physical, distributed mass balance model for Zhadang glacier (central Tibet, 30° N, based on in-situ measurements over 2009–2011 and an uncertainty estimate by Monte Carlo and ensemble strategies. The model application aims to provide the first quantification of how the Indian Summer Monsoon (ISM impacts an entire glacier over the various stages of the monsoon's annual cycle. We find a strong and systematic ISM footprint on the interannual scale. Early (late monsoon onset causes higher (lower accumulation, and reduces (increases the available energy for ablation primarily through changes in absorbed shortwave radiation. By contrast, only a weak footprint exists in the ISM cessation phase. Most striking though is the core monsoon season: local mass and energy balance variability is fully decoupled from the active/break cycle that defines large-scale atmospheric variability during the ISM. Our results demonstrate quantitatively that monsoon onset strongly affects the ablation season of glaciers in Tibet. However, we find no direct ISM impact on the glacier in the main monsoon season, which has not been acknowledged so far. This result also adds cryospheric evidence that regional modification of the large-scale monsoon flow prevails on the Tibetan Plateau in summer.

  16. The importance of glacier and forest change in hydrological climate-impact studies

    Directory of Open Access Journals (Sweden)

    N. Köplin

    2012-05-01

    Full Text Available Changes in land cover alter the water balance components of a catchment, due to strong interactions between soils, vegetation and the atmosphere. Therefore, hydrological climate impact studies should also integrate scenarios of associated land cover change. To reflect two severe climate-induced changes in land cover, we applied scenarios of glacier retreat and forest cover increase that were derived from the temperature signals of the climate scenarios used in this study. The climate scenarios consist of ten regional climate models from the ENSEMBLES project; their respective temperature and precipitation deltas are used to run a hydrological model. The relative importance of each of the three types of scenarios (climate, glacier, forest is assessed through an analysis of variance (ANOVA. Altogether, 15 mountainous catchments in Switzerland are analysed, exhibiting different degrees of glaciation during the control period (0–51% and different degrees of forest cover increase under scenarios of change (12–55% of the catchment area. The results show that even an extreme change in forest cover is negligible with respect to changes in runoff, but it is crucial as soon as evaporation or soil moisture is concerned. For the latter two variables, the relative impact of forest change is proportional to the magnitude of its change. For changes that concern 35% of the catchment area or more, the effect of forest change on summer evapotranspiration is equally or even more important than the climate signal. For catchment with a glaciation of 10% or more in the control period, the glacier retreat significantly determines summer and annual runoff. The most important source of uncertainty in hydrological climate impact studies is the climate scenario, though, and it is highly recommended to apply an ensemble of climate scenarios in impact studies. The results presented here are valid for the climatic region they were tested for, i.e. a humid, mid

  17. Generation of the relationship between glacier area and volume for a tropical glacier in Bolivian Andes

    Science.gov (United States)

    Liu, T.; Kinouchi, T.; Hasegawa, A.; Tsuda, M.; Iwami, Y.; Asaoka, Y.; Mendoza, J.

    2015-12-01

    In Andes, retreat of tropical glaciers is rapid, thus water resources currently available from glacierized catchments would be changed in its volume and temporal variations due to climate change and glacier shrinkage. The relationship between glacier area and volume is difficult to define however which is important to monitor glaciers especially those are remote or inaccessible. Water resources in La Paz and El Alto in Bolivia, strongly depend on the runoff from glacierized headwater catchments in the Cordillera Real, Andes, which is therefore selected as our study region.To predict annual glacier mass balances, PWRI-Distributed Hydrological Model (PWRI-DHM) was applied to simulate runoff from the partially glacierized catchments in high mountains (i.e. Condoriri-Huayna West headwater catchment located in the Cordillera Real, Bolivian Andes). PWRI-DHM is based on tank model concept in a distributed and 4-tank configuration including surface, unsaturated, aquifer, and river course tanks. The model was calibrated and validated with observed meteorological and hydrological data from 2011 to 2014 by considering different phases of precipitation, various runoff components from glacierized and non-glacierized areas, and the retarding effect by glacial lakes and wetlands. The model is then applied with MRI-AGCM outputs from 1987 to 2003 considering the shrinkage of glacier outlines since 1980s derived from Landsat data. Annual glacier mass balance in each 100m-grid was reproduced, with which the glacier area-volume relationship was generated with reasonable initial volume setting. Out study established a method to define the relationship between glacier area and volume by remote sensing information and glacier mass balances simulated by distributed hydrological model. Our results demonstrated that the changing trend of local glacier had a consistency the previous observed glacier area-volume relationship in the Cordillera Real.

  18. Holocene glacier fluctuations and climate changes in the southeastern part of the Russian Altai (South Siberia) based on a radiocarbon chronology

    Science.gov (United States)

    Agatova, A. R.; Nazarov, A. N.; Nepop, R. K.; Rodnight, H.

    2012-06-01

    This study investigates glacier dynamic and climatic variations in the southeastern part of the Russian Altai (SE Altai) during the last 7000 years. Recent glacier retreats and ice melting in moraines has led to exhumation of organic material allowing the possibility of radiocarbon dating. We report here 57 new radiocarbon dates from wood remains buried by moraines and from proglacial forefields, from peat layers and lacustrine sediments that cover moraines, from dead trees at the upper tree limit, and from rock glaciers on trough slopes from six glacial valleys in the North Chuya Range, SE Altai. Such a numerous dataset for the vast but unified in neotectonic and climatic conditions area is presented for the first time the history of research in the Altai. Together with 62 previously published radiocarbon ages, mainly of fossil soils and peat layers in the foot of the ranges in SE Altai, they form the basis for understanding the relative magnitudes and timing of the most important glacial and climatic events of SE Altai. New data refute the traditional concept of the Russian Altai Holocene glaciations as a consecutive retreat of the late Würm glaciers and argue their complete degradation at the head of trough valleys at least 7000 cal. years BP. Moraine complexes of three Holocene glacial stages are morphologically expressed in trough valleys of the North Chuya range. They correlate with three identified periods of glacial advances: from 4900 to 4200 cal. years BP (Akkem stage), from 2300 to 1700 cal. years BP (Historical stage) and in the 13th-19th centuries (Little Ice Age (LIA) or Aktru stage). The coincident extremes of lowering temperature and increasing precipitation during the Akkem stage led to abrupt glacier advances and forming of the most remote moraine complexes downstream in the valleys. Following glacier advances had distinctly smaller magnitudes. In addition to the radiocarbon data, the time limits of the Historical stage were defined more

  19. CHANGING OF THE ALTAI GLACIER SYSTEM SINCE THE MID-TWENTIETH CENTURY AND ITS RESPONSE TO THE CLIMATE WARMING IN FUTURE

    Directory of Open Access Journals (Sweden)

    V. M. Kotlyakov

    2012-01-01

    Full Text Available Characteristics of the Altai glacier system are analyzed on the data from Chinese and Former Soviet Union glacier inventories. Two glacier data sets, recent remote sensing data and the glacier inventories data were compared. It has been found that 208 glaciers disappeared and the glacial area decreased by 12%. Functional models of the glacier system variations have been developed using the equation of relationship between an annual glacier ablation and a mean summer temperature; the glacier system structure and behavior of the equilibrium line altitudes at the steady state were taken into account as well. The models were used to study response of the glacial runoff to a climatic change. The model results show that, under the climate warming scenario of 0.05°С/year, only 3% Altai glaciers inChinaand 9% inRussiawill remain by the end of this century.

  20. Peeking Under the Ice… Literally: Records of Arctic Climate Change from Radiocarbon Dating Moss Emerging from Beneath Retreating Glaciers

    Science.gov (United States)

    Briner, J. P.; Schweinsberg, A.; Miller, G. H.; Lifton, N. A.; Beel, C. R.; Bennike, O.

    2014-12-01

    Dramatic changes are taking place throughout the Arctic. Many glaciers have already melted away completely, and most others are well on their way as rising snowline elevations promise continued glacier retreat. Emerging from beneath retreating glacier margins is a landscape rich in information about past climate and glacier changes. Within newly exposed bedrock is an inventory of cosmogenic nuclides that archive past ice cover timing and duration. Lake basins re-appearing due to retreating ice preserve sediment archives that tell of cooling climate and advancing ice. And ancient surfaces vegetated with tundra communities that have long been entombed beneath frozen-bedded ice caps are now being revealed for the first time in millennia. This presentation will focus on the climate and glacier record derived from radiocarbon dating of in situ moss recently exhumed from retreating local ice cap margins on western Greenland. Dozens of radiocarbon ages from moss group into several distinct modes, which are interpreted as discrete times of persistent summer cooling and resultant glacier expansion. The data reveal a pattern of glacier expansion beginning ~5000 years ago, followed by periods of glacier growth around 3500 and 1500 years ago. Because these times of glacier expansion are recorded at many sites in western Greenland and elsewhere in the Arctic, they are interpreted as times of step-wise summer cooling events during the Holocene. These non-linear climate changes may be a result of feedbacks that amplify linear insolation forcing of Holocene climate. In addition to these insights into the Arctic climate system, the antiquity of many radiocarbon ages of ice-killed moss indicate that many arctic surfaces are being re-exposed for the first time in millennia due to retreating ice, emphasizing the unprecedented nature of current summer warming.

  1. Reconstructing glacier-based climates of LGM Europe and Russia – Part 2: A dataset of LGM precipitation/temperature relations derived from degree-day modelling of palaeo glaciers

    Directory of Open Access Journals (Sweden)

    R. Allen

    2008-11-01

    Full Text Available The study of European and Russian Quaternary glacial-geological evidence during the last 15 years has generated sufficient data to use former glacial extent as a proxy for Last Glacial Maximum (LGM climate (precipitation and temperature at a continental scale. Utilisation of such data is relevant for two reasons. First, continental to global scale proxy reconstructions of past climate are an important tool in the assessment of retrospective general circulation model (GCM simulations. Second, the development of a multi-proxy approach will result in a more robust proxy based climate signal. A new and independent dataset of 36 LGM precipitation and temperature relationships derived from European and Russian mountain regions is presented in this paper. A simple glacier-climate model was used to establish the optimum LGM precipitation/temperature conditions for each region from a suite of over 4000 model climates using the principle of zero cumulative mass balance. Clear regional trends are present in the reconstructed LGM precipitation and temperature curves; assuming present precipitation temperature anomalies north of the Alps are 2°C and 5°C larger than those in the western and eastern Mediterranean, respectively. In Russia the model results suggest that the climates in both the Arctic Urals and Puterana Plateau were probably conducive to the existence of small mountain glaciers at the LGM.

  2. Re-analysis of Alaskan benchmark glacier mass-balance data using the index method

    Science.gov (United States)

    Van Beusekom, Ashely E.; O'Nell, Shad R.; March, Rod S.; Sass, Louis C.; Cox, Leif H.

    2010-01-01

    At Gulkana and Wolverine Glaciers, designated the Alaskan benchmark glaciers, we re-analyzed and re-computed the mass balance time series from 1966 to 2009 to accomplish our goal of making more robust time series. Each glacier's data record was analyzed with the same methods. For surface processes, we estimated missing information with an improved degree-day model. Degree-day models predict ablation from the sum of daily mean temperatures and an empirical degree-day factor. We modernized the traditional degree-day model and derived new degree-day factors in an effort to match the balance time series more closely. We estimated missing yearly-site data with a new balance gradient method. These efforts showed that an additional step needed to be taken at Wolverine Glacier to adjust for non-representative index sites. As with the previously calculated mass balances, the re-analyzed balances showed a continuing trend of mass loss. We noted that the time series, and thus our estimate of the cumulative mass loss over the period of record, was very sensitive to the data input, and suggest the need to add data-collection sites and modernize our weather stations.

  3. Research advances on climate-induced slope instability in glacier and permafrost high-mountain environments

    OpenAIRE

    C. Huggel; Fischer, L.; Schneider, D.; Haeberli, W.

    2002-01-01

    High-mountain areas with glacier and permafrost occurrence are temperature sensitive environments. Climatic changes are, thus, likely to have an effect on slope stability. Several recent events have shown that rock and ice avalanches and related hazards can have severe consequences. For hazard analysis, the processes of slope failure and flow dynamics should therefore be better understood. In this article, recent advances in this field are presented, including high-res...

  4. Climate, glaciers and permafrost in the Swiss Alps 2050: scenarios, consequences and recommendations

    OpenAIRE

    Haeberli, W.; Hohmann, R.

    2008-01-01

    Climate scenarios for the time horizon of 2050 in the Swiss Alps as simulated by using high-resolution ensemble modeling indicate most likely changes in temperature /precipitation by + 2°C / + 10% in winter and + 3°C / - 20% in summer. Such a development would lead to the vanishing of about 75% of the existing glacier surface and deep warming of permafrost in mountain peaks. Corresponding impacts would mainly concern rather dramatic changes in landscape appearance, slope stability and the...

  5. 中国冰川系统对气候变化响应的敏感性分析%Sensitivity analysis of glacier systems to climate warming in China

    Institute of Scientific and Technical Information of China (English)

    王欣; 谢自楚; 李巧媛; 王淑红; 程磊

    2008-01-01

    Data of 44 glacier systems in China used in this paper were obtained from Chinese Glacier Inventories and the meteorological data were got from Meteorological Atlas of Plateau of west China. Based on the statistical analysis and functional model simulation results of the 44 glacier systems in China, the glacier systems were divided into extremely-sensitive glacier system, semi-sensitive glacier system, extremely-steady glacier system and semi-steady glacier system in terms of glacier system's level of water-energy exchange, rising gradient of the equilibrium line altitudes and retreating rate of area to climate warming, their median size and vertical span distribution, and their runoff characteristics to climate warming. Furthermore,the functional model of glacier system to climate warming was applied in this paper to predict the average variation trends of the 4 types of glacier systems, which indicate that different sensitivity types of glacier systems respond to the climate warming differently.

  6. Favorable climatic regime for maintaining the present-day geometry of the Gregoriev Glacier, Inner Tien Shan

    Directory of Open Access Journals (Sweden)

    K. Fujita

    2011-07-01

    Full Text Available We conducted 2 yr (2005–2007 of in situ meteorological and glaciological observations on the Gregoriev Glacier, a flat-top glacier within the Inner Tien Shan, Kyrgyzstan. Relative carrier-phase GPS surveys reveal a vertical lowering at the summit of the glacier. Based on snow density data and an energy-mass balance model, we estimate that the annual precipitation and summer mean temperature required to maintain the glacier in the current state are 289 mm and −3.8 °C at the glacier summit (4600 m a.s.l., respectively. The good agreement between dynamically derived precipitation and the long-term observed precipitation at a nearby station in the Tien Shan (296 mm at 3614 m a.s.l. for the period 1930–2002 suggests that the glacier has been in a near steady-state in terms of mass supply. The glacier mass-balance, reconstructed based on meteorological data from the Tien Shan station for the past 80 yr, explains the observed fluctuations in glacier extent, particularly the negative mass balance in the 1990s.

  7. Glacier Retreat in the Southern Peruvian Andes: Climate Change, Environmental Impacts, Human Perception and Social Response

    Science.gov (United States)

    Orlove, B.

    2007-12-01

    This paper presents results from recent environmental and anthropological research near glacierized areas in the department of Cusco, Peru, home to the well-known Quelccaya Ice Cap and to the peak of Ausangate (6384 m). Glaciers in the region are in negative mass balance, losing volume and area, with upslope movement of the glacier fronts. Somewhat paradoxically, flows in many streams close to the glaciers are reduced, particularly in the dry season, due to a shift in the seasonal distribution of melting, to increased evaporation and to increased percolation into newly-exposed sands and gravels. Associated with this reduction in flow is a desiccation of some anthropogenic and natural wetlands, reducing the availability of dry season forage to wild (vicuna) and domesticated (alpaca, llama) ruminants. Interviews and ethnographic observations with local populations of Quechua-speaking herders at elevations of 4500-5200 meters provide detailed comments on these changes. They have an extensive vocabulary of terms for glacial features associated with retreat. They link this treat with environmental factors (higher temperatures, greater winds that deposit dust on lower portions of glaciers) and with religious factors (divine punishment for human wrong-doing, failure of humans to respect mountain spirits). They describe a variety of economic and extra-economic impacts of this retreat on different spatial, social and temporal scales. Though they face other issues as well (threats of pollution from new mining projects, inadequacy of government services), glacier retreat is their principal concern. Many herders express extreme distress over this unprecedented threat to their livelihoods and communities, though a few propose responses - out-migration, the formation of an association of neighboring communities, development of irrigation works - that could serve as adaptations.

  8. Listening to Glaciers: Passive hydroacoustics near marine-terminating glaciers

    Science.gov (United States)

    Pettit, E.C.; Nystuen, J.A.; O'Neel, Shad

    2012-01-01

    The catastrophic breakup of the Larsen B Ice Shelf in the Weddell Sea in 2002 paints a vivid portrait of the effects of glacier-climate interactions. This event, along with other unexpected episodes of rapid mass loss from marine-terminating glaciers (i.e., tidewater glaciers, outlet glaciers, ice streams, ice shelves) sparked intensified study of the boundaries where marine-terminating glaciers interact with the ocean. These dynamic and dangerous boundaries require creative methods of observation and measurement. Toward this effort, we take advantage of the exceptional sound-propagating properties of seawater to record and interpret sounds generated at these glacial ice-ocean boundaries from distances safe for instrument deployment and operation.

  9. Future of Himalayan glaciers: Projections from CMIP5 and CORDEX climate models and their uncertainties

    Science.gov (United States)

    Jury, Martin W.; Mendlik, Thomas; Tani, Satyanarayana; Truhetz, Heimo; Ragettli, Silvan; Pellicciotti, Francesca; Immerzeel, Walter

    2016-04-01

    Glaciers are of key importance to the freshwater supply in the Himalayan region. Their growth or melting is influenced by an interaction of temperature near the surface (tas) and precipitation rate (pr). In a changing climate characterized by rising temperatures mountain glaciers are ought to decline. However, recent observations indicate a glacier growth over the Karakoram (western Himalaya) due to a rise in snow accumulation while positive degree days show no change. To further investigate this behavior and to clarify whether this glacier growth is intermediate we use a model ensemble encompassing 34 GCMs of the CMIP5, 5 RCMs of the East-Asia CORDEX, as well as 3 RCMs of the South-Asia CORDEX for 3 different representative concentration pathways. The models' ability to correctly reproduce local weather patterns is accounted for via temporal and spatial correlations to observed tas and pr over the southern ridge of the Himalaya. APHRODITE is used as observational data. The reanalyses ERA-Interim, NCEP/NCAR and JRA-55 are used to further account for observational uncertainty. tas and pr of all climate simulations have been bias corrected (quantile mapping) in order to obtain snow accumulation and positive degree days. Finally, the uncertainty of the projected trends of the climate model ensemble has been quantified. First results indicate a uniform rise of positive degree days over all scenarios leading to a higher melting rate. However, this uniform behavior is in contrast to changes in snow accumulation, for which some models project an increase and others a decrease until the end of the century.

  10. Climate change effects on Glacier recession in Himalayas using Multitemporal SAR data and Automatic Weather Station observations

    Science.gov (United States)

    Kumar, V.; Singh, S. K.; Venkataraman, G.

    2009-04-01

    The Himalaya is the highest but the youngest mountain belt (20 to 60 million years B.P.) of the earth running in arc shape for about 2500 km. It has more than 90 peaks above 6000 m and contains about 50% of all glaciers outside of the polar environments (Bahadur, 1993). All glaciers in this region are in general recession since last 150 years (Paul et al.,1979). Gangotri, Siachen, Bara Shigri and Patsio are major glaciers in this region which are showing retreat with different rates and their respective tributary glaciers are completely disconnected from main body of glaciers. Spaceborne synthetic aperture radar data provide an important tool for monitoring the fluctuation of the glaciers. In this paper attempt has been made for quantifying the glacier retreat using multitemporal synthetic aperture radar (SAR) data. SAR intensity and phase information will be exploited separately under SAR intensity tracking and interferometric SAR (InSAR) coherence tracking (Strozzi et al., 2002) respectively. Glacier retreat study have been done using time series coregistered multi temporal SAR images. Simultaneously InSAR coherence thresholding is applied for tracking the snout of Gangotri glacier. It is observed that glacier is retreating at the rate of 21 m/a. Availability of high resolution spotlight mode TerraSAR-X SAR data will supplement the ENVISAT ASAR and ERS-1/2 based observations. The observatory in the proximity of Gangotri glacier has been made functional at Bhojbasa and all weather parameters viz. Snow fall, temperature, pressure, air vector, column water vapor and humidity are recorded twice a day as per WMO standards manually and automatically. Three Automatic Weather Stations (AWS) have been established in the glacier area at Bhojbasa , Kalindipass and Nandaban. Since Himalayan environment is presently under great stress of decay and degeneration, AWS data will be analyzed in the context of climate change effects on fluctuation of glaciers. References 1.Jagdish

  11. Mass-balance reconstruction for Glacier No. 354, Tien Shan, from 2003 to 2014

    OpenAIRE

    2016-01-01

    This study presents a reconstruction of the seasonal mass balance of Glacier No. 354, located in the Akshiirak range, Kyrgyzstan, from 2003 to 2014. We use a distributed accumulation and temperature-index melt model driven by daily air temperature and precipitation from a nearby meteorological station. The model is calibrated with in situ measurements of the annual mass balance collected from 2011 to 2014. The snow-cover depletion pattern observed using satellite imagery provides additional i...

  12. Mass loss of Greenland's glaciers and ice caps 2003-2008 revealed from ICES at laser altimetry data

    DEFF Research Database (Denmark)

    Bolch, T.; Sørensen, Louise Sandberg; Simonsen, Sebastian Bjerregaard;

    2013-01-01

    The recently finalized inventory of Greenland's glaciers and ice caps (GIC) allows for the first time to determine the mass changes of the GIC separately from the ice sheet using space-borne laser altimetry data. Corrections for firn compaction and density that are based on climatic conditions...... are applied for the conversion from volume to mass changes. The GIC which are clearly separable from the icesheet (i.e., have a distinct ice divide or no connection) lost 27.9 ± 10.7 Gt a-1 or 0.08 ± 0.03 mm a-1 sea-level equivalent (SLE) between October 2003 and March 2008. All GIC (including those...

  13. Compositional characteristics of n-alkanes of the glaciers over the Tibetan Plateau and their environmental and climatic significances

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    We report on the concentration and compositional features of n-alkanes of natural and anthropogenic origins in the snow samples collected from the Qiyi glacier in the Qilian Mountains, the Yuzhufeng glacier in eastern Kunlun Mountains, the Xiaodongkemadi glacier in the Tanggula Mountains, and the Gurenhekou glacier in the Nyainqêntanglha Range. The results indicate a decrease in the total n-alkane concentration (T-HCs) from the northeast to the south over the Tibetan Plateau. The T-HCs in these studied areas were close to those in the Belukha and Sofiyskiy glacier, Russian Alati Mountains and the Dasuopu glacier in the Himalaya but were much higher than those in the Greenland ice sheet, suggesting that the mountain glaciers in the Asian continent may receive a higher loading of n-alkanes than the Greenland ice core. Moreover, the compositional characteristics of n-alkanes indicated that the n-alkanes in the studied areas were probably originated from the plant waxes as well as the fossil-fuel combustion exhaust, whereas the contribution from the lower organisms was small. In addition, the plant wax (Cn(wax)) and anthropogenic (non-Cn(wax)) contributions revealed that fast industrialization may have significant effects on the organic pollutant composition in glacier over the Tibetan Plateau and its circumference environment. Particularly, except for the Yuzhufeng glacier, the ΣnC21-/ΣnC22+ and (nC15+nC17+nC19)/(nC27+nC29+nC31) ratio decreased from the Qiyi glacier to the Gurenhekou glacier over the Tibetan Plateau, while the carbon preference index (CPI) values increased. These results indicate a decrease in terrigenous input while an increase in marine input from the northeast to the south over the Tibetan Plateau. These two ratios can be used as the climatic and environmental change indicators.

  14. Long term mass balance of the Helheim and Kangerdlugssuaq glaciers in southeast Greenland

    Science.gov (United States)

    Khan, Shfaqat Abbas; Fitzner, Antje; Kjær, Kurt; Korsgaard, Niels; Aschwanden, Andy; Bjørk, Anders; Bevan, Suzanne; Kjeldsen, Kristian; Bueler, Edward; Luckman, Adrian; van den Broeke, Michiel

    2013-04-01

    Observations over the past decade show huge ice loss associated with speeding up of glaciers in southeast Greenland in 2003, followed by a deceleration in 2006. These short-term episodic dynamic perturbations have a major impact on the mass balance at decadal scale. However, to improve the projection of future sea level rise, a long-term data record that reveals the mass balance between episodic events is required. Here, we extend the observational record of marginal thinning of Helheim glacier (HG) and Kangerdlugssuaq glacier (KG) from 7 to 30 years. Our measurements reveal that, although the frontal portion of HG thinned by more than 100 m during 2003-2006, it thickened by more than 50 m during 1981-1997. During the same periods, KG was stable until 1998 and experienced major thinning only after 2003. Analyses of their sensitivity to sea surface temperature (SST) anomalies and variations in air temperature suggest that both outlet glaciers respond immediately to small fluctuations in both the SST and air temperature. Furthermore, we compare our observations of ice flow speed and elevation changes with predictions based on the The Parallel Ice Sheet Model (PISM) software.

  15. Global application of a surface mass balance model using gridded climate data

    OpenAIRE

    R. H. Giesen; Oerlemans, J.

    2012-01-01

    Global applications of surface mass balance models have large uncertainties, as a result of poor climate input data and limited availability of mass balance measurements. This study addresses several possible consequences of these limitations for the modelled mass balance. This is done by applying a simple surface mass balance model that only requires air temperature and precipitation as input data, to glaciers in different regions. In contrast to other models used in global applications...

  16. The Glaciers of HARMONIE

    Science.gov (United States)

    Mottram, Ruth; Gleeson, Emily; Pagh Nielsen, Kristian

    2016-04-01

    Developed by the large ALADIN-HIRLAM consortium, the numerical weather prediction (NWP) model system HARMONIE is run by a large number of national weather services and research institutions in Europe, the Middle East and North Africa for weather forecasting. It is now being adopted for climate research purposes as a limited area model in a form known as HCLIM. It is currently run for a number of domains, mostly in Europe but also including Greenland, at a very high resolution (~2.5 km). HARMONIE is a convection permitting non-hydrostatic model that includes the multi-purpose SURFEX surface model. By improving the characterization of glacier surfaces within SURFEX we show that weather forecast errors over both the Greenland ice sheet and over Icelandic glaciers can be significantly reduced. The improvements also facilitate increasingly accurate ice melt and runoff computations, which are important both for ice surface mass balance estimations and hydropower forecasting. These improvements will also benefit the operational HARMONIE domains that cover the Svalbard archipelago, the Alps and the Scandinavian mountain glaciers. Future uses of HCLIM for these regions, where accurately characterizing glacial terrain will be crucial for climate and glaciological applications, are also expected to benefit from this improvement. Here, we report the first results with a new glacier surface scheme in the HARMONIE model, validated with observations from the PROMICE network of automatic weather stations in Greenland. The scheme upgrades the existing surface energy balance over glaciers by including a new albedo parameterization for bare glacier ice and appropriate coefficients for calculating the turbulent fluxes. In addition the snow scheme from the SURFEX land surface module has been upgraded to allow the retention and refreezing of meltwater in the snowpack. These changes allow us to estimate surface mass balance over glaciers at a range of model resolutions that can take full

  17. Batura-Glacier - mass balance and 'Karakoram Anomaly' (Upper Hunza, Karakoram)

    Science.gov (United States)

    Boerst, U.; Winiger, M.; Bookhagen, B.

    2013-12-01

    In line with an almost worldwide trend the (non-surging) glaciers in the Hindukush-Karakoram-Himalaya Range manifest a remarkable down melting of their tongues and retreating of their terminuses in the last few decades. A series of recent studies prove an overall negative mass balance for most of the Himalayan glaciers. Contrary to these statements various publications register stable or positive mass balances for a number of glaciers located in the NW-Karakoram Mountains - postulating the so-called 'Karakoram-Anomaly'. Unlike the many investigations in the Himalaya, the Karakoram records very few detailed local investigations emphasizing the spatial and temporal development of glaciers. This presentation focuses on the Batura Glacier in NW-Karakorum in Gilgit-Baltistan (Pakistan). With a west-to-east extension of ~ 57 km and an elevation range of 5.3 km (2.500 - 7.800 masl), the Batura Glacier belongs to the worldwide largest glaciers in the mid and low latitudes. Detailed mapping and further ground-based investigations have been carried out in the 1920ies, 1953/59, 1974/5 and in the past few years by different research teams. In order to determine the glacier's mass balance for the last 50 years we relied on Digital Elevation Models (DEMs): digitized maps from 1959 and 1974 are compared to DEMs derived through stereogrammetry from ASTER-scenes for 2001, 2006, 2008, 2010 and 2011. The ASTER-DEMs were post-processed with various correction methods and techniques to insure the relative DEM comparability and include corrections for aspect, altitude, and tilt. Next, we calculated surface differences from the ice and snow-free areas with respect to the SRTM C-Band DEM. Our remote sensing techniques are supplemented by differential GPS measurements and ice-surface profiles from 2013 as well as by multi-temporal photography matching. Preliminary results indicate a significant down melting of the glacier tongue from 1959 to the present day and acceleration during the past

  18. Climatic records in a firn core from an Alpine temperate glacier on Mt. Yulong, southeastern part of the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    He Yuanqing; Yao Tandong; Cheng Guodong; Yang Meixue

    2001-01-01

    @@ Mt. Yulong is the southernmost glacier-covered area in Eurasia, including China. There are 19 sub-tropical temperate glaciers on the mountain, controlled by the southwestern monsoon climate. In the summer of 1999,a firn core, 10.10 m long, extending down to glacier ice,was recovered in the accumulation area of the largest glacier, Baishui No. 1. Periodic variations of climatic signals above 7.8 m depth were apparent, and net accumulation off our years was identified by the annual oscillations of isotopic and ionic composition. The boundaries of annual accumulation were confirmed by higher values of electrical conductivity and pH, and by dirty refreezing ice layers at the levels of summer surfaces.

  19. Brief Communication: Contending estimates of 2003-2008 glacier mass balance over the Pamir-Karakoram-Himalaya

    Science.gov (United States)

    Kääb, A.; Treichler, D.; Nuth, C.; Berthier, E.

    2015-03-01

    We present glacier thickness changes over the entire Pamir-Karakoram-Himalaya arc based on ICESat satellite altimetry data for 2003-2008. We highlight the importance of C-band penetration for studies based on the SRTM elevation model. This penetration seems to be of potentially larger magnitude and variability than previously assumed. The most negative rate of region-wide glacier elevation change (mass-gain anomaly rather than its centre. For the Ganges, Indus and Brahmaputra basins, the glacier mass change reaches -24 ± 2 Gt yr-1, about 10% of the current glacier contribution to sea-level rise. For selected catchments, we estimate glacier imbalance contributions to river run-off from a few percent to greater than 10%.

  20. Reconstructing glacier-based climates of LGM Europe and Russia – Part 1: Numerical modelling and validation methods

    Directory of Open Access Journals (Sweden)

    A. J. Payne

    2007-10-01

    Full Text Available The mountain environments of mid-latitude Europe and Arctic Russia contain widespread evidence of Late-Quaternary glaciers that have been prescribed to the Last Glacial Maximum (LGM. This glacial-geological record has yet to be used to quantitatively reconstruct the LGM climate of these regions. Here we describe a simple glacier-climate model that can be used to derive regional temperature and precipitation information from a known glacier distribution. The model was tested against the present day distribution of glaciers in Europe. The model is capable of adequately predicting the spatial distribution, snowline and equilibrium line altitude climate of glaciers in the Alps, Scandinavia, Caucasus and Pyrenees Mountains. This verification demonstrated that the model can be used to investigate former climates such as the LGM. Reconstructions of LGM climates from proxy evidence are an important method of assessing retrospective general circulation model (GCM simulations. LGM palaeoclimate reconstructions from glacial-geological evidence would be of particular benefit to investigations in Europe and Russia, where to date only fossil pollen data have been used to assess continental-scale GCM simulations.

  1. Reconstructing glacier-based climates of LGM Europe and Russia – Part 1: Numerical modelling and validation methods

    Directory of Open Access Journals (Sweden)

    R. Allen

    2008-11-01

    Full Text Available The mountain environments of mid-latitude Europe and Arctic Russia contain widespread evidence of Late-Quaternary glaciers that have been attributed to the Last Glacial Maximum (LGM. This glacial-geological record has yet to be used to quantitatively reconstruct the LGM climate of these regions. Here we describe a simple glacier-climate model that can be used to derive regional temperature and precipitation information from a known glacier distribution. The model was tested against the present day distribution of glaciers in Europe. The model is capable of adequately predicting the spatial distribution, snowline and equilibrium line altitude climate of glaciers in the Alps, Scandinavia, Caucasus and Pyrenees Mountains. This verification demonstrated that the model can be used to investigate former climates such as the LGM. Reconstructions of LGM climates from proxy evidence are an important method of assessing retrospective general circulation model (GCM simulations. LGM palaeoclimate reconstructions from glacial-geological evidence would be of particular benefit to investigations in Europe and Russia, where to date only fossil pollen data have been used to assess continental-scale GCM simulations.

  2. Study on the glacier variation and its runoff responses in the arid region of Northwest China

    Institute of Scientific and Technical Information of China (English)

    刘潮海; 康尔泗; 刘时银; 陈建明; 刘宗香

    1999-01-01

    The glaciers in the arid region of Northwest China are viewed as an independent system, and glacier variation and mass balance fluctuation since the Little Ice Age and in the recent decades are estimated. Based on the estimation, the threshold time of glacier runoff against the backgrounds of the current and future varying climate conditions is simulated.

  3. Deriving historical equilibrium-line altitudes from a glacier length record by linear inverse modelling

    NARCIS (Netherlands)

    Klok, E.J.; Oerlemans, J.

    2003-01-01

    Glaciers have fluctuated in historic times and the length fluctuations of many glaciers are known. From these glacier length records, a climate reconstruction described in terms of a reconstruction of the equilibrium-line altitude (ELA) or the mass-balance can be extracted. In order to derive a clim

  4. Climate change and glacier retreat drive shifts in an Antarctic benthic ecosystem.

    Science.gov (United States)

    Sahade, Ricardo; Lagger, Cristian; Torre, Luciana; Momo, Fernando; Monien, Patrick; Schloss, Irene; Barnes, David K A; Servetto, Natalia; Tarantelli, Soledad; Tatián, Marcos; Zamboni, Nadia; Abele, Doris

    2015-11-01

    The Antarctic Peninsula (AP) is one of the three places on Earth that registered the most intense warming in the last 50 years, almost five times the global mean. This warming has strongly affected the cryosphere, causing the largest ice-shelf collapses ever observed and the retreat of 87% of glaciers. Ecosystem responses, although increasingly predicted, have been mainly reported for pelagic systems. However, and despite most Antarctic species being benthic, responses in the Antarctic benthos have been detected in only a few species, and major effects at assemblage level are unknown. This is probably due to the scarcity of baselines against which to assess change. We performed repeat surveys of coastal benthos in 1994, 1998, and 2010, analyzing community structure and environmental variables at King George Island, Antarctica. We report a marked shift in an Antarctic benthic community that can be linked to ongoing climate change. However, rather than temperature as the primary factor, we highlight the resulting increased sediment runoff, triggered by glacier retreat, as the potential causal factor. The sudden shift from a "filter feeders-ascidian domination" to a "mixed assemblage" suggests that thresholds (for example, of tolerable sedimentation) and alternative equilibrium states, depending on the reversibility of the changes, could be possible traits of this ecosystem. Sedimentation processes will be increasing under the current scenario of glacier retreat, and attention needs to be paid to its effects along the AP.

  5. Impact of sublimation losses in the mass balance of glaciers in semi-arid mountain regions

    Science.gov (United States)

    Ayala, Alvaro; Pellicciotti, Francesca; Burlando, Paolo; MacDonell, Shelley; McPhee, James

    2016-04-01

    Glaciers in semiarid mountain regions may lose an important part of their winter snow accumulation through sublimation processes that are enhanced by the high-elevation, intense radiation and dry atmosphere of these environments. As glaciers in these regions secure freshwater resources to lower valleys during summer and drought periods, it is important to advance in a detailed quantification of their sublimation losses. However, logistical concerns and complex meteorological features make the measuring and modelling of glacier mass balances a difficult task. In this study, we estimated the spring-summer mass balances of Tapado and Juncal Norte glaciers in the semiarid Andes of north-central Chile by running a distributed energy balance model that accounts for melt, refreezing and sublimation from the surface and blowing snow. Meteorological input data were available from on-glacier Automatic Weather Stations (AWS) that were installed during the ablation season of years 2005-06, 2008-09, 2013-14 and 2014-15. Snow pits, ablation stakes and a time-lapse camera that provided surface albedo were also available. Distributed air temperature and wind speed were dynamically downscaled from NASA MERRA reanalysis using the software WINDSIM and validated against the data from the AWSs. The rest of the meteorological variables were distributed using statistical relations with air temperature derived from the AWSs data. Initial snow conditions were estimated using satellite images and distributed manual snow depth measurements. Preliminary results show that total ablation diminishes with elevation and that, during the early ablation season (October-November), melt is the main ablation component below 4500 m with sublimation dominating the ablation above this elevation. Above 4500 m an important fraction of meltwater refreezes during night. As the ablation season advances (December-February), melt extends to higher elevations, refreezing plays a smaller role and sublimation is

  6. Brief Communication: Contending estimates of early 21st century glacier mass balance over the Pamir-Karakoram-Himalaya

    Directory of Open Access Journals (Sweden)

    A. Kääb

    2014-11-01

    Full Text Available We present glacier thickness changes over the entire Pamir-Karakoram-Himalaya arc based on ICESat satellite altimetry data for 2003–2008. The strongest thinning (−1 is observed for the East Nyainqêntanglha Shan. Conversely, glaciers of the West Kunlun Shan are slightly gaining volume, and Pamir and Karakoram seem to be on the western edge of an anomaly rather than its centre. For the Ganges, Indus and Brahmaputra basins, the glacier mass change reaches −22 ± 3 Gt yr−1, about 10% of the current glacier contribution to sea-level rise. For selected catchments over the study area we estimate glacier imbalance contributions to river runoff from a few percent to far over 10%. We highlight the importance of C-band penetration for studies based on the SRTM elevation model. To the very east and west of our study area, this penetration seems to be of larger magnitude and variability than previously assumed.

  7. Survey of glaciers in the northern Rocky Mountains of Montana and Wyoming; Size response to climatic fluctuations 1950-1996

    Energy Technology Data Exchange (ETDEWEB)

    Chatelain, E.E. [Valdosta State Univ., GA (United States)

    1997-09-01

    An aerial survey of Northern Rocky Mountain glaciers in Montana and Wyoming was conducted in late summer of 1996. The Flathead, Swan, Mission, and Beartooth Mountains of Montana were covered, as well as the Teton and Wind River Ranges of Wyoming. Present extent of glaciers in this study were compared to limits on recent USGS 15 and 7.5 topographic maps, and also from selected personal photos. Large cirque and hanging glaciers of the Flathead and Wind River Ranges did not display significant decrease in size or change in terminus position. Cirque glaciers in the Swan, Mission, Beartooth and Teton Ranges were markedly smaller in size; with separation of the ice body, growth of the terminus lake, or cover of the ice terminus with rockfalls. A study of annual snowfall, snowdepths, precipitation, and mean temperatures for selected stations in the Northern Rocky Mountains indicates no extreme variations in temperature or precipitation between 1950-1996, but several years of low snowfall and warmer temperatures in the 1980`s appear to have been sufficient to diminish many of the smaller cirque glaciers, many to the point of extinction. The disappearance of small cirque glaciers may indicate a greater sensitivity to overall climatic warming than the more dramatic fluctuations of larger glaciers in the same region.

  8. Future glacier runoff at the global scale

    Science.gov (United States)

    Huss, Matthias; Hock, Regine

    2016-04-01

    Water resources in mountain areas worldwide importantly depend on the runoff contribution by glaciers. Glacial water storage acts as an equilibrating element in the global hydrological cycle on various temporal scales. With ongoing and future glacier retreat a growing concern regarding water supply security in glacier-fed basins arises. However, glacier runoff projections at the regional or global scale are still rare and better models are urgently needed for planning and adaptation measures to cope with a changing seasonal distribution of water yields. Moreover, it is still an open debate in which region "peak water" - the maximum contribution of melting glaciers to runoff - has already been reached, i.e. whether increasing or declining annual runoff volumes must be expected. Here, we present results of a novel global glacier model for calculating the 21st century response of surface mass balance, three-dimensional glacier geometry and monthly water discharge for each individual glacier around the globe. The current surface geometry and thickness distribution for each of the world's roughly 200'000 glaciers is extracted from the Randolph Glacier Inventory and terrain models. Our simulations are driven with 14 Global Circulation Models from the CMIP5 project using the RCP4.5, RCP8.5 and RCP2.6 scenarios. We focus on the timing of peak water from glacierized catchments in all climatic regions of the earth and the corresponding importance of changes in the runoff regime on hydrological stress. The maximum rate of water release from glacial storage is subject to a high spatio-temporal variability depending on glacier characteristics and the transient response to climatic change. Furthermore, we discuss the significance of projected variations in glacier runoff in relation to the hydrology of the world's large-scale drainage basins and population distribution, and highlight 'hot spot' regions where the wastage of current ice volume is particularly relevant.

  9. Decrease, Increase or Stability? Glacier Response to Climate Change in the Trans-Himalayas of Ladakh, Northern India

    Science.gov (United States)

    Schmidt, Susanne; Nüsser, Marcus

    2010-05-01

    The eastern and central parts of the Greater Himalayas display a general picture of rapidly melting glaciers, whereas the glaciers in the western Himalayas, Hindu Kush and Karakorum show a more differentiated response to climate change. It includes individual advancing glaciers and relatively stable snout positions. The Trans-Himalayan region of Ladakh is possibly located at the interface between shrinking and advancing or stable glaciers. The region is characterized by cold and arid conditions (mean annual air temperature amounts 5.6 °C and precipitation 93 mm in Leh, 3545 m a.s.l.), while the influence of the monsoon is rather limited. Due to low summer precipitation and the variability of winter snow fall, glaciers largely determine the potentials and limitations of irrigated crop cultivation, forming the primary basis of subsistence agriculture and regional food security. The glaciers of Ladakh are located above 5200 m a.s.l. and according to their small size (generally less than 2 km²), their response to climate change is expected to be direct and predictable. To detect and to quantify glacier changes in different aspects of the NNW-SSE oriented Kang Yatze Massif (6401 m a.s.l.), which is sandwiched between the Zanskar and Stok Ranges, multi-temporal and multi-scale remote sensing data were used. In order to map the changes of glacier covered areas two panchromatic Corona images from 1969 were compared to a high resolution panchromatic Worldview image from 2009. The data gap of the 40 years period was filled with Spot images (1991, 2006), and several Landsat and Aster data. To identify and quantify the glacierized areas a semi-automatic thresholding approach was applied for the co-registered multi-spectral datasets. Additionally, the delineation of glaciers was manually digitized on the panchromatic images. First results for the time period between 1969 and 2009 reveal a minor decrease of almost all investigated glaciers in the Kang Yatze Massif. In order to

  10. Contrasting responses of Central Asian rock glaciers to global warming.

    Science.gov (United States)

    Sorg, Annina; Kääb, Andreas; Roesch, Andrea; Bigler, Christof; Stoffel, Markus

    2015-02-06

    While the responses of Tien Shan glaciers--and glaciers elsewhere--to climatic changes are becoming increasingly well understood, this is less the case for permafrost in general and for rock glaciers in particular. We use a novel approach to describe the climate sensitivity of rock glaciers and to reconstruct periods of high and low rock glacier activity in the Tien Shan since 1895. Using more than 1500 growth anomalies from 280 trees growing on rock glacier bodies, repeat aerial photography from Soviet archives and high-resolution satellite imagery, we present here the world's longest record of rock glacier movements. We also demonstrate that the rock glaciers exhibit synchronous periods of activity at decadal timescales. Despite the complex energy-balance processes on rock glaciers, periods of enhanced activity coincide with warm summers, and the annual mass balance of Tuyuksu glacier fluctuates asynchronously with rock glacier activity. At multi-decadal timescales, however, the investigated rock glaciers exhibit site-specific trends reflecting different stages of inactivation, seemingly in response to the strong increase in air temperature since the 1970s.

  11. The current disequilibrium of North Cascade glaciers

    Science.gov (United States)

    Pelto, Mauri S.

    2006-03-01

    Three lines of evidence indicate that North Cascade (Washington, USA) glaciers are currently in a state of disequilibrium. First, annual balance measured on nine glaciers yields a mean cumulative balance for the 1984-2004 period of -8.58 m water equivalent (w.e.), a net loss of ice thickness exceeding 9.5 m. This is a significant loss for glaciers that average 30-50 m in thickness, representing 18-32% of their entire volume.Second, longitudinal profiles completed in 1984 and 2002 on 12 North Cascade glaciers confirm this volume change indicating a loss of -5.7 to -6.3 m in thickness (5.0-5.6 m w.e.) between 1984 and 2002, agreeing well with the measured cumulative balance of -5.52 m w.e. for the same period. The change in thickness on several glaciers has been equally substantial in the accumulation zone and the ablation zone, indicating that there is no point to which the glacier can retreat to achieve equilibrium. Substantial thinning along the entire length of a glacier is the key indicator that a glacier is in disequilibrium.Third, North Cascade glacier retreat is rapid and ubiquitous. All 47 glaciers monitored are currently undergoing significant retreat or, in the case of four, have disappeared. Two of the glaciers where mass balance observations were begun, Spider Glacier and Lewis Glacier, have disappeared. The retreat since 1984 of eight Mount Baker glaciers that were all advancing in 1975 has averaged 297 m. These observations indicate broad regional continuity in glacial response to climate.

  12. Glacier mass balance reconstruction by sublimation induced enrichment of chemical species on Cerro Tapado (Chilean Andes

    Directory of Open Access Journals (Sweden)

    P. Ginot

    2006-01-01

    Full Text Available A 36 m long ice core down to bedrock from the Cerro Tapado glacier (5536 m a.s.l, 30°08' S, 69°55' W was analyzed to reconstruct past climatic conditions for Northern Chile. Because of the marked seasonality in the precipitation (short wet winter and extended dry summer periods in this region, major snow ablation and related post-depositional processes occur on the glacier surface during summer periods. They include predominantly sublimation and dry deposition. Assuming that, like measured during the field campaign, the enrichment of chloride was always related to sublimation, the chemical record along the ice core may be applied to reconstruct the history of such secondary processes linked to the past climatic conditions over northern Chile. For the time period 1962–1999, a mean annual net accumulation of 316 mm water equivalent (weq and 327 mm weq loss by sublimation was deduced by this method. This corresponds to an initial total annual accumulation of 539 mm weq. The annual variability of the accumulation and sublimation is related with the Southern Oscillation Index (SOI: higher net-accumulation during El-Niño years and more sublimation during La Niña years. The deepest part of the ice record shows a time discontinuity; with an ice body deposited under different climatic conditions: 290 mm higher precipitation but with reduced seasonal distribution (+470 mm in winter and –180 mm in summer and –3°C lower mean annual temperature. Unfortunately, its age is unknown. The comparison with regional proxy data however let us conclude that the glacier buildup did most likely occur after the dry mid-Holocene.

  13. Climatic control on extreme sediment transfer from Dokriani Glacier during monsoon, Garhwal Himalaya (India)

    Science.gov (United States)

    Kumar, Amit; Verma, Akshaya; Dobhal, Dwarika Prasad; Mehta, Manish; Kesarwani, Kapil

    2014-02-01

    In the Himalayas, most of the glaciers are covered by thick debris, especially in the ablation zone. Supraglacial debris cover might play an important role for sediment budget of the glaciated area or for the ablation of ice masses mantled in debris. During summer season, proglacial meltwater carries considerable amount of suspended sediment. The deglaciated area provides a ready source of sediment during Indian Summer Monsoon (ISM). The heavy sediment load from the glaciers affects the hydropower generation, irrigation and drinking water supply. Therefore, to understand the sediment delivery from glaciated basins, characteristics and variation of the suspended sediment concentrations in the proglacial meltwater stream, Dokriani Glacier, have been monitored during the ablation season (May-September). Suspended sediment samples were collected near the snout of Dokriani Glacier, Garhwal Himalaya, in 2010 and 2011. Results show that mean monthly suspended sediment concentrations (SSC) were 1499, 2303, 3845 and 1649 mg/l for the months June, July, August, and September, respectively, indicating highest concentration in August followed by July. Over the period of recording, daily mean suspended concentration in the melt stream varied from 13-9798.2 mg/l, which is very high, caused due to a flash flood event during the monitoring period. The mean daily suspended sediment concentration was computed to be 2196 mg/l. The suspended sediment concentration begins to increase with discharge from May and reduces in September. Present study provides TRMM (Tropical Rainfall Measuring Mission) derived and field based hydro-meteorological insight about severe rainstorms during the years 2010 and 2011 in the study area, which transported large amounts of sediment.

  14. Climatic control on extreme sediment transfer from Dokriani Glacier during monsoon, Garhwal Himalaya (India)

    Indian Academy of Sciences (India)

    Amit Kumar; Akshaya Verma; Dwarika Prasad Dobhal; Manish Mehta; Kapil Kesarwani

    2014-02-01

    In the Himalayas, most of the glaciers are covered by thick debris, especially in the ablation zone. Supraglacial debris cover might play an important role for sediment budget of the glaciated area or for the ablation of ice masses mantled in debris. During summer season, proglacial meltwater carries considerable amount of suspended sediment. The deglaciated area provides a ready source of sediment during Indian Summer Monsoon (ISM). The heavy sediment load from the glaciers affects the hydropower generation, irrigation and drinking water supply. Therefore, to understand the sediment delivery from glaciated basins, characteristics and variation of the suspended sediment concentrations in the proglacial meltwater stream, Dokriani Glacier, have been monitored during the ablation season (May– September). Suspended sediment samples were collected near the snout of Dokriani Glacier, Garhwal Himalaya, in 2010 and 2011. Results show that mean monthly suspended sediment concentrations (SSC) were 1499, 2303, 3845 and 1649 mg/l for the months June, July, August, and September, respectively, indicating highest concentration in August followed by July. Over the period of recording, daily mean suspended concentration in the melt stream varied from 13–9798.2 mg/l, which is very high, caused due to a flash flood event during the monitoring period. The mean daily suspended sediment concentration was computed to be 2196 mg/l. The suspended sediment concentration begins to increase with discharge from May and reduces in September. Present study provides TRMM (Tropical Rainfall Measuring Mission) derived and field based hydro-meteorological insight about severe rainstorms during the years 2010 and 2011 in the study area, which transported large amounts of sediment.

  15. On the impact of using downscaled reanalysis data instead of direct measurements for modeling the mass balance of a tropical glacier (Cordillera Blanca, Peru)

    Science.gov (United States)

    Galos, Stephan; Hofer, Marlis; Marzeion, Ben; Mölg, Thomas; Großhauser, Martin

    2013-04-01

    Due to their setting, tropical glaciers are sensitive indicators of mid-tropospheric meteorological variability and climate change. Furthermore these glaciers are of particular interest because they respond faster to climatic changes than glaciers located in mid- or high-latitudes. As long-term direct meteorological measurements in such remote environments are scarce, reanalysis data (e.g. ERA-Interim) provide a highly valuable source of information. Reanalysis datasets (i) enable a temporal extension of data records gained by direct measurements and (ii) provide information from regions where direct measurements are not available. In order to properly derive the physical exchange processes between glaciers and atmosphere from reanalysis data, downscaling procedures are required. In the present study we investigate if downscaled atmospheric variables (air temperature and relative humidity) from a reanalysis dataset can be used as input for a physically based, high resolution energy and mass balance model. We apply a well validated empirical-statistical downscaling model, fed with ERA-Interim data, to an automated weather station (AWS) on the surface of Glaciar Artesonraju (8.96° S | 77.63° W). The downscaled data is then used to replace measured air temperature and relative humidity in the input for the energy and mass balance model, which was calibrated using ablation data from stakes and a sonic ranger. In order to test the sensitivity of the modeled mass balance to the downscaled data, the results are compared to a reference model run driven solely with AWS data as model input. We finally discuss the results and present future perspectives for further developing this method.

  16. Integrated analysis of environmental drivers, spatiotemporal variability and rates of contemporary chemical and mechanical fluvial denudation in selected glacierized and non-glacierized cold climate catchment systems

    Science.gov (United States)

    Beylich, Achim A.

    2016-04-01

    There is, by today, an impressive number of quantitative process geomorphic studies presenting contemporary chemical or mechanical fluvial denudation rates from a wide range of cold climate catchment geo-systems worldwide. However, the number of quantitative studies that actually considers and includes all three main components of fluvial transport, i.e. solute transport, suspended sediment transport and bedload transport, is actually rather small. Most of the existing studies include one or, at best, two of these main components. At the same time, it is generally accepted that a knowledge of the quantitative shares of fluvial solute, suspended sediment and bedload transport of the total fluvial transport, together with detailed information on sediment sources and sediment storage, is needed for the reliable quantitative construction and understanding of present-day sedimentary budgets. In this contribution, results from longer-term process geomorphic work conducted in selected glacierized and non-glacierized high-latitude and high-altitude cold climate catchment systems in Norway, Iceland, Sweden and Finland are compared. The size of the six studied catchment geo-systems ranges from 7.0 km2 to 79.5 km2. Contemporary chemical and mechanical fluvial denudation rates measured in the defined catchment systems with different cold climates, varying degrees of glacier coverage, different lithologies and general sediment availabilities, different catchment morphometries, and varying degrees of vegetation cover are presented. By direct comparisons between the six different catchments environmental controls of the computed annual denudation rates are detected and the spatial variability of the contemporary chemical and mechanical fluvial denudation rates found across the different cold climate catchment systems is explained. Annual fluvial denudation rates generally increase with increasing topographic relief, increasing mean slope angles, increasing annual precipitation

  17. HIMALA: Climate Impacts on Glaciers, Snow, and Hydrology in the Himalayan Region

    Science.gov (United States)

    Brown, Molly Elizabeth; Ouyang, Hua; Habib, Shahid; Shrestha, Basanta; Shrestha, Mandira; Panday, Prajjwal; Tzortziou, Maria; Policelli, Frederick; Artan, Guleid; Giriraj, Amarnath; Bajracharya, Sagar R.; Racoviteanu, Adina

    2010-01-01

    Glaciers are the largest reservoir of freshwater on Earth, supporting one third of the world s population. The Himalaya possess one of the largest resources of snow and ice, which act as a freshwater reservoir for more than 1.3 billion people. This article describes a new project called HIMALA, which focuses on utilizing satellite-based products for better understanding of hydrological processes of the river basins of the region. With support from the US Agency for International Development (USAID), the International Centre for Integrated Mountain Development (ICIMOD), together with its partners and member countries, has been working on the application of satellite-based rainfall estimates for flood prediction. The US National Aeronautics and Space Administration (NASA) partners are working with ICIMOD to incorporate snowmelt and glacier melt into a widely used hydrological model. Thus, through improved modeling of the contribution of snow and ice meltwater to river flow in the region, the HIMALA project will improve the ability of ICIMOD and its partners to understand the impact of weather and climate on floods, droughts, and other water- and climate-induced natural hazards in the Himalayan region in Afghanistan, Bangladesh, Bhutan, China, India, Myanmar, Nepal, and Pakistan.

  18. Integration of glacier databases within the Global Terrestrial Network for Glaciers (GTN-G)

    Science.gov (United States)

    Zemp, M.; Raup, B. H.; Armstrong, R.; Ballagh, L.; Gärtner-Roer, I.; Haeberli, W.; Hoelzle, M.; Kääb, A.; Kargel, J.; Paul, F.

    2009-04-01

    Changes in glaciers and ice caps provide some of the clearest evidence of climate change and have impacts on global sea level fluctuations, regional hydrological cycles and local natural hazard situations. Internationally coordinated collection and distribution of standardized information about glaciers and ice caps was initiated in 1894 and is today coordinated within the Global Terrestrial Network for Glaciers (GTN-G). A recently established GTN-G Steering Committee coordinates, supports and advices the operational bodies responsible for the international glacier monitoring, which are the World Glacier Monitoring Service (WGMS), the US National Snow and Ice Data Center (NSIDC) and the Global Land Ice Measurements from Space (GLIMS) initiative. In this presentation, we provide an overview of (i) the integration of the various operational databases, (ii) the development of a one-stop web-interface to these databases, and (iii) the available datasets. By joint efforts consistency and interoperability of the different glacier databases is elaborated. Thereby, the lack of a complete worldwide, detailed glacier inventory as well as different historical developments and methodological contexts of the datasets are major challenges for linking individual glaciers throughout the databases. A map-based web-interface, implemented based on OpenLayer 2.0 and Web Map/Feature Services, is elaborated to spatially link the available data and to provide data users a fast overview of all available data. With this new online service, GTN-G provides fast access to information on glacier inventory data from 100,000 glaciers mainly based on aerial photographs and from 80,000 glaciers mainly based on satellite images, length change series from 1,800 glaciers, mass balance series from 230 glaciers, special events (e.g., hazards, surges, calving instabilities) from 130 glaciers, as well as 10,000 photographs from some 470 glaciers.

  19. Brief Communication: Contending estimates of early 21st century glacier mass balance over the Pamir-Karakoram-Himalaya

    Science.gov (United States)

    Kääb, A.; Nuth, C.; Treichler, D.; Berthier, E.

    2014-11-01

    We present glacier thickness changes over the entire Pamir-Karakoram-Himalaya arc based on ICESat satellite altimetry data for 2003-2008. The strongest thinning (mass change reaches -22 ± 3 Gt yr-1, about 10% of the current glacier contribution to sea-level rise. For selected catchments over the study area we estimate glacier imbalance contributions to river runoff from a few percent to far over 10%. We highlight the importance of C-band penetration for studies based on the SRTM elevation model. To the very east and west of our study area, this penetration seems to be of larger magnitude and variability than previously assumed.

  20. Modeling debris-covered glaciers: extension due to steady debris input

    OpenAIRE

    L. S. Anderson; Anderson, R. S.

    2015-01-01

    Debris-covered glaciers are common in rapidly-eroding alpine landscapes. When thicker than a few centimeters, surface debris suppresses melt rates. If continuous debris cover is present, mass balance gradients can be reduced leading to increases in glacier length. In order to quantify feedbacks in the debris-glacier-climate system, we developed a 2-D long-valley numerical glacier model that includes englacial and supraglacial advection. We ran 120 simulations in which a steady state debris-fr...

  1. Numerical modeling of Glacier d'Argentiere and its historic front variations

    OpenAIRE

    Huybrechts, Philippe; Nooze, P. de; Decleir, H.

    1989-01-01

    A numerical glacier model has been developed for Glacier d'Argentiere (France) in order to study its relation with climate and investigate possible causes forthe observed variations in the terminus record since the beginning of the Little Ice Age. At first results are presented from a basic sensitivity investigation,with plots of steady state glacier length versus perturbations in mass balance and glacier reaction with respect to sinusoidal net balance oscillations. An attemptis then made to ...

  2. Surface characteristics and evolution of debris covered glaciers

    Science.gov (United States)

    Mölg, Nico; Vieli, Andreas; Bolch, Tobias; Bauder, Andreas; Bhattacharya, Atanu

    2016-04-01

    Global climate change has led to increasing glacier retreat in most parts of the world. However, many heavily debris-covered glaciers have shown much smaller recession rates than their clean-ice neighbours. This can be attributed to the insulation effect of the supraglacial debris. Remote-sensing based investigations revealed that recent mass balances of debris-covered glaciers are equally negative. This fact is partly due to enhanced melting at supra-glacial lakes and ice cliffs but can also be caused by reduced mass flux. In this context, insufficient process understanding constitutes a major challenge for large scale glacier change assessment and modelling. In this project, we aim at better understanding the evolution of glaciers in connection with changes in supra-glacial debris coverage. It is performed on Zmutt Glacier in Matter valley in Switzerland and on Gangotri Glacier in Garwhal Himalaya in India. Changes in glacier length, area, debris coverage, and surface elevation were compiled based on topographic maps, oblique photos, aerial and satellite orthoimages, digital terrain models (DTMs), and glacier monitoring data for a 50 (Gangotri) and 120 (Zmutt) year period, respectively. The subsequent analysis revealed that Zmutt Glacier has been in a slow but almost continuous retreating state since the end of the 19th century and showed a clear reduction in glacier area and volume. Similarly, Gangotri Glacier has retreated and, to a smaller degree, lost volume. However, the change in glacier length and area is clearly smaller than for other nearby, less debris-covered or debris-free glaciers. This fact is attributed to the larger debris-covered area that has steadily increased. Further in the project, this data will serve as an important input and validation for the envisaged 3D flow modelling and, hence, will contribute to the understanding of the development of glaciers and debris-covered ice in a period of fast climatic changes.

  3. Internationally coordinated glacier monitoring: strategy and datasets

    Science.gov (United States)

    Hoelzle, Martin; Armstrong, Richard; Fetterer, Florence; Gärtner-Roer, Isabelle; Haeberli, Wilfried; Kääb, Andreas; Kargel, Jeff; Nussbaumer, Samuel; Paul, Frank; Raup, Bruce; Zemp, Michael

    2014-05-01

    Internationally coordinated monitoring of long-term glacier changes provide key indicator data about global climate change and began in the year 1894 as an internationally coordinated effort to establish standardized observations. Today, world-wide monitoring of glaciers and ice caps is embedded within the Global Climate Observing System (GCOS) in support of the United Nations Framework Convention on Climate Change (UNFCCC) as an important Essential Climate Variable (ECV). The Global Terrestrial Network for Glaciers (GTN-G) was established in 1999 with the task of coordinating measurements and to ensure the continuous development and adaptation of the international strategies to the long-term needs of users in science and policy. The basic monitoring principles must be relevant, feasible, comprehensive and understandable to a wider scientific community as well as to policy makers and the general public. Data access has to be free and unrestricted, the quality of the standardized and calibrated data must be high and a combination of detailed process studies at selected field sites with global coverage by satellite remote sensing is envisaged. Recently a GTN-G Steering Committee was established to guide and advise the operational bodies responsible for the international glacier monitoring, which are the World Glacier Monitoring Service (WGMS), the US National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. Several online databases containing a wealth of diverse data types having different levels of detail and global coverage provide fast access to continuously updated information on glacier fluctuation and inventory data. For world-wide inventories, data are now available through (a) the World Glacier Inventory containing tabular information of about 130,000 glaciers covering an area of around 240,000 km2, (b) the GLIMS-database containing digital outlines of around 118,000 glaciers with different time stamps and

  4. Global application of a surface mass balance model using gridded climate data

    Directory of Open Access Journals (Sweden)

    R. H. Giesen

    2012-04-01

    Full Text Available Global applications of surface mass balance models have large uncertainties, as a result of poor climate input data and limited availability of mass balance measurements. This study addresses several possible consequences of these limitations for the modelled mass balance. This is done by applying a simple surface mass balance model that only requires air temperature and precipitation as input data, to glaciers in different regions. In contrast to other models used in global applications, this model separately calculates the contributions of net solar radiation and the temperature-dependent fluxes to the energy balance. We derive a relation for these temperature-dependent fluxes using automatic weather station (AWS measurements from glaciers in different climates. With local, hourly input data, the model is well able to simulate the observed seasonal variations in the surface energy and mass balance at the AWS sites. Replacing the hourly local data by monthly gridded climate data removes summer snowfall and winter melt events and hence influences the modelled mass balance most on locations with a small seasonal temperature cycle. Representative values for the multiplication factor and vertical gradient of precipitation are determined by fitting modelled winter mass balance profiles to observations on 80 glaciers in different regions. For 72 of the 80 glaciers, the precipitation provided by the climate data set has to be multiplied with a factor above unity; the median factor is 2.55. The vertical precipitation gradient ranges from negative to positive values, with more positive values for maritime glaciers and a median value of 1.5 mm a−1 m. With calibrated precipitation, the modelled annual mass balance gradient closely resembles the observations on the 80 glaciers, the absolute values are matched by adjusting either the incoming solar radiation, the temperature-dependent flux or the air temperature. The mass balance sensitivity to

  5. Global application of a surface mass balance model using gridded climate data

    Science.gov (United States)

    Giesen, R. H.; Oerlemans, J.

    2012-04-01

    Global applications of surface mass balance models have large uncertainties, as a result of poor climate input data and limited availability of mass balance measurements. This study addresses several possible consequences of these limitations for the modelled mass balance. This is done by applying a simple surface mass balance model that only requires air temperature and precipitation as input data, to glaciers in different regions. In contrast to other models used in global applications, this model separately calculates the contributions of net solar radiation and the temperature-dependent fluxes to the energy balance. We derive a relation for these temperature-dependent fluxes using automatic weather station (AWS) measurements from glaciers in different climates. With local, hourly input data, the model is well able to simulate the observed seasonal variations in the surface energy and mass balance at the AWS sites. Replacing the hourly local data by monthly gridded climate data removes summer snowfall and winter melt events and hence influences the modelled mass balance most on locations with a small seasonal temperature cycle. Representative values for the multiplication factor and vertical gradient of precipitation are determined by fitting modelled winter mass balance profiles to observations on 80 glaciers in different regions. For 72 of the 80 glaciers, the precipitation provided by the climate data set has to be multiplied with a factor above unity; the median factor is 2.55. The vertical precipitation gradient ranges from negative to positive values, with more positive values for maritime glaciers and a median value of 1.5 mm a-1 m. With calibrated precipitation, the modelled annual mass balance gradient closely resembles the observations on the 80 glaciers, the absolute values are matched by adjusting either the incoming solar radiation, the temperature-dependent flux or the air temperature. The mass balance sensitivity to changes in temperature is

  6. Exploring uncertainty in glacier mass balance modelling with Monte Carlo simulation

    Directory of Open Access Journals (Sweden)

    H. Machguth

    2008-06-01

    Full Text Available By means of Monte Carlo simulations we calculated uncertainty in modelled cumulative mass balance over 400 days at one particular point on the tongue of Morteratsch Glacier, Switzerland, using a glacier energy balance model of intermediate complexity. Before uncertainty assessment, the model was tuned to observed mass balance for the investigated time period and its robustness was tested by comparing observed and modelled mass balance over 11 years, yielding very small deviations. Both systematic and random uncertainties are assigned to twelve input parameters and their respective values estimated from the literature or from available meteorological data sets. The calculated overall uncertainty in the model output is dominated by systematic errors and amounts to 0.7 m w.e. or approximately 10% of total melt over the investigated time span. In order to provide a first order estimate on variability in uncertainty depending on the quality of input data, we conducted a further experiment, calculating overall uncertainty for different levels of uncertainty in measured global radiation and air temperature. Our results show that the output of a well calibrated model is subject to considerable uncertainties, in particular when applied for extrapolation in time and space where systematic errors are likely to be an important issue.

  7. Exploring uncertainty in glacier mass balance modelling with Monte Carlo simulation

    Directory of Open Access Journals (Sweden)

    H. Machguth

    2008-12-01

    Full Text Available By means of Monte Carlo simulations we calculated uncertainty in modelled cumulative mass balance over 400 days at one particular point on the tongue of Morteratsch Glacier, Switzerland, using a glacier energy balance model of intermediate complexity. Before uncertainty assessment, the model was tuned to observed mass balance for the investigated time period and its robustness was tested by comparing observed and modelled mass balance over 11 years, yielding very small deviations. Both systematic and random uncertainties are assigned to twelve input parameters and their respective values estimated from the literature or from available meteorological data sets. The calculated overall uncertainty in the model output is dominated by systematic errors and amounts to 0.7 m w.e. or approximately 10% of total melt over the investigated time span. In order to provide a first order estimate on variability in uncertainty depending on the quality of input data, we conducted a further experiment, calculating overall uncertainty for different levels of uncertainty in measured global radiation and air temperature. Our results show that the output of a well calibrated model is subject to considerable uncertainties, in particular when applied for extrapolation in time and space where systematic errors are likely to be an important issue.

  8. More Data and Better Tools for the GLIMS Glacier Database

    Science.gov (United States)

    Raup, B. H.; Armstrong, R. L.; Cogley, J. G.; Hock, R.

    2015-12-01

    Earth's glaciers are changing rapidly in response to a changing climate, and this has implications for people in numerous ways, such as increased hazards from glacial lake outburst floods, changes to water resources, and increasing sea level. To understand these changes, it is vitally important to monitor glaciers through time, measuring their areal extent, changes in volume, flow velocities, snow lines, elevation distribution, and changes to associated water bodies. The glacier database of the Global Land Ice Measurements from Space (GLIMS) initiative is the only multi-temporal glacier database capable of tracking all these glacier measurements and providing them to the scientific community and broader public.This contribution presents recent results in 1) expansion of the GLIMS Glacier Database in geographic coverage by drawing on the Randolph Glacier Inventory (RGI) and other new data sets; 2) new tools for visualizing and downloading GLIMS data in a choice of formats and data models; 3) a new data model for handling multiple glacier records through time while avoiding double-counting of glacier number or area; and 4) a new system of collaboration between all members of the glacier mapping community to streamline the process of meeting various community needs. The result of this work promises to be an improved glacier data repository that will be useful for tracking changes in water resources, hazards, and mass budgets of the world's glaciers.

  9. Estimating Permafrost Distribution in the Maritime Southern Alps, New Zealand, Based on Climatic Conditions at Rock Glacier Sites

    OpenAIRE

    Sattler, Katrin; Anderson, Brian; Mackintosh, Andrew; Norton, Kevin; de Róiste, Mairéad

    2016-01-01

    Alpine permafrost occurrence in maritime climates has received little attention, despite suggestions that permafrost may occur at lower elevations than in continental climates. To assess the spatial and altitudinal limits of permafrost in the maritime Southern Alps, we developed and tested a catchment-scale distributed permafrost estimate. We used logistic regression to identify the relationship between permafrost presence at 280 active and relict rock glacier sites and the independent variab...

  10. Estimating permafrost distribution in the maritime Southern Alps, New Zealand, based on climatic conditions at rock glacier sites

    OpenAIRE

    Katrin eSattler; Brian eAnderson; Andrew eMackintosh; Kevin eNorton; Mairéad ede Róiste

    2016-01-01

    Alpine permafrost occurrence in maritime climates has received little attention, despite suggestions that permafrost may occur at lower elevations than in continental climates. To assess the spatial and altitudinal limits of permafrost in the maritime Southern Alps, we developed and tested a catchment-scale distributed permafrost estimate. We used logistic regression to identify the relationship between permafrost presence at 280 active and relict rock glacier sites and the independent variab...

  11. Glacier area changes in Northern Eurasia

    International Nuclear Information System (INIS)

    Glaciers are widely recognized as key indicators of climate change. Recent evidence suggests an acceleration of glacier mass loss in several key mountain regions. Glacier recession implies landscape changes in the glacial zone, the origin of new lakes and activation of natural disaster processes, catastrophic mudflows, ice avalanches, outburst floods, etc. The absence or inadequacy of such information results in financial and human losses. A more comprehensive evaluation of glacier changes is imperative to assess ice contributions to global sea level rise and the future of water resources from glacial basins. One of the urgent steps is a full inventory of all ice bodies and their changes. The first estimation of glacier state and glacier distribution on the territory of the former Soviet Union has been done in the USSR Glacier Inventory (UGI) published in 1965–1982. The UGI is based on topographic maps and air photos and reflects the status of the glaciers in the 1940s–1970s. There is information about 28 884 glaciers with an area of 7830.75 km2 in the inventory. It covers 25 glacier systems in Northern Eurasia. In the 1980s the UGI has been transformed into digital form as a part of the World Glacier Inventory (WGI). Recent satellite data provide a unique opportunity to look again at these glaciers and to evaluate changes in glacier extent for the second part of the 20th century. About 15 000 glacier outlines for the Caucasus, Polar Urals, Pamir Alay, Tien Shan, Altai, Kamchatka and Russian Arctic have been derived from ASTER and Landsat imagery and can be used for glacier change evaluation. Results of the analysis indicate the steady trend in glacier shrinkage in all mountain regions for the second part of the 20th century. Glacier area loss for the studied regions varies from 13% (Tien Shan) to 22.3% (Polar Urals). The common driver, most likely, is an increase in summer air temperature. There is also a very large variability in the degree of individual

  12. Multilevel spatiotemporal validation of snow/ice mass balance and runoff modeling in glacierized catchments

    Science.gov (United States)

    Hanzer, Florian; Helfricht, Kay; Marke, Thomas; Strasser, Ulrich

    2016-08-01

    In this study, the fully distributed, physically based hydroclimatological model AMUNDSEN is set up for catchments in the highly glacierized Ötztal Alps (Austria, 558 km2 in total). The model is applied for the period 1997-2013, using a spatial resolution of 50 m and a temporal resolution of 1 h. A novel parameterization for lateral snow redistribution based on topographic openness is presented to account for the highly heterogeneous snow accumulation patterns in the complex topography of the study region. Multilevel spatiotemporal validation is introduced as a systematic, independent, complete, and redundant validation procedure based on the observation scale of temporal and spatial support, spacing, and extent. This new approach is demonstrated using a comprehensive set of eight independent validation sources: (i) mean areal precipitation over the period 1997-2006 derived by conserving mass in the closure of the water balance, (ii) time series of snow depth recordings at the plot scale, (iii-iv) multitemporal snow extent maps derived from Landsat and MODIS satellite data products, (v) the snow accumulation distribution for the winter season 2010/2011 derived from airborne laser scanning data, (vi) specific surface mass balances for three glaciers in the study area, (vii) spatially distributed glacier surface elevation changes for the entire area over the period 1997-2006, and (viii) runoff recordings for several subcatchments. The results indicate a high overall model skill and especially demonstrate the benefit of the new validation approach. The method can serve as guideline for systematically validating the coupled components in integrated snow-hydrological and glacio-hydrological models.

  13. Compositional characteristics of n-alkanes of the glaciers over the Tibetan Plateau and their environmental and climatic significances

    Institute of Scientific and Technical Information of China (English)

    LI QuanLian; WANG NingLian; WU XiaoBo; PU JianChen; HE JianQiao; XIE Jun

    2009-01-01

    State Key Laboratory of Cryospheric Science,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,ChinaWe report on the concentration and compositional features of n-alkanes of natural and anthropogenic origins in the snow samples collected from the Qiyi glacier in the Qilian Mountains,the Yuzhufeng glacier in eastern Kunlun Mountains,the Xiaodongkemadi glacier in the Tanggula Mountains,and the concentration (T-HCs) from the northeast to the south over the Tibetan Plateau.The T-HCs in these studied areas were close to those in the Belukha and Sofiyskiy glacier,Russian Alati Mountains and the Dasuopu glacier in the Himalaya but were much higher than those in the Greenland ice sheet,suggesting that the mountain glaciers in the Asian continent may receive a higher loading of n-alkanes than the Greenland ice core.Moreover,the compositional characteristics of n-alkanes indicated that the n-alkanes in the studied areas were probably originated from the plant waxes as well as the fossil-fuel combustion exhaust,whereas the contribution from the lower organisms was small.In addition,the plant wax (C_n(wax)) and anthropogenic (non-C_n(wax)) contributions revealed that fast industrialization may have significant effects on the organic pollutant composition in glacier over the Tibetan Plateau and its circumference environment.Particularly,except for the Yuzhufeng glacier,the ∑nC_(21)~-/∑nC_(22)~+ and (nC_(15) +nC_(17)+nC_(19))/(nC_(27)+nC_(29)+nC_(31)) ratio decreased from the Qiyi glacier to the Gurenhekou glacier over the Tibetan Plateau,while the carbon preference index (CPI) values increased.These results indicate a decrease in terrigenous input while an increase in marine input from the northeast to the south over the Tibetan Plateau.These two ratios can be used as the climatic and environmental change indicators.

  14. A positive mass balance appeared at Urumuqi Glacier No.1 in 2009%乌鲁木齐河源1号冰川2009年出现物质正平衡

    Institute of Scientific and Technical Information of China (English)

    张国飞; 李忠勤; 王文彬; 王卫东

    2013-01-01

    Tianshan Mountains Glacier No. 1 experienced glacier nine times positive balance fluctuation and nine times negative balance fluctuation, the rates of negative balance years with positive balance years are 35:16. With global warming,the Urumqi Glacier No.l is retreating and thinning rapidly,especially from 1997 to 2009,there are continuous 12 negative balance observation years at Tianshan Mountains Glacier No.l. It shows that the Glacier No.l in a strong negative numerical balance, and the strongest negative balance, -931 mm. w.e., emerges from 2008 during the observation period. And what' s more, the cumulative mass balance reaches 13 709 mm. w.e. in 2008. But in 2009,the mass balance is positive,63 mm. w.e.,and the inter-annual change up to 1 062 mm. w.e.. Glacier mass balance is highly sensitive to changes in temperature and precipitation , which makes them become important indicators of climate change. When temperature reach the higher or lower, the mass balance of warm season supplied Glacier controlled by the temperature though the precipitation is great or small, Summer air temperature is the main control factors for the change of glacier mass balance. By analyzing the observation data of mass balances, air temperature and precipitation at Urumuqi Glacier No.l between 2007/08 and 2008/09, the lower summer temperature is the main factor to result in the phenomenon. The lower summer temperature caused the start time of glacial ablation period was delayed and the end time of glacier ablation was advanced, so the loss mass reduced. And, secondly, increase annual precipitation is one of factor represent addition of mass to the glacier.

  15. Warming and drying of tundra and glacier summer climate in NW Spitsbergen from 1975 to 2014

    Directory of Open Access Journals (Sweden)

    Przybylak Rajmund

    2016-06-01

    Full Text Available Temperature and precipitation conditions in the Kaffiøyra region in the summer season (21 July–31 August for the period from 1975–2014 are described based on data collected during 22 expeditions, in which meteorological measurements were carried out, and complete data series combining both original and reconstructed data. The latter ones were obtained using data from the Ny Ålesund meteorological station, which are strongly correlated with data from the Kaffiøyra region. Seasonal statistics presented for temperature and precipitation based on these two sets of data reveal only slight changes. Summer temperatures in the Kaffiøyra region in the studied period (1975–2014 showed statistically significant strong upward trends, while precipitation totals revealed a downward trend, but not statistically significant. In the studied area, based on 40-years of data, it was demonstrated that the near-surface lapse rates of summer air temperature are slightly lower in glaciated (0.58°C/100 m than in non-glaciated areas (0.67°C/100 m. Anticyclonic/cyclonic circulation types significantly increase/decrease air temperature on the Waldemar Glacier, while their impact on precipitation is markedly smaller. In summer, close correlations were observed between air temperature and such glacier characteristics as the mass balance and the location of the equilibrium line, while precipitation does not have a great influence on them.

  16. Climate Change, Glacier Retreat and Sediment Waves: Evidences from Fans in the Fox Glacial valley (New Zealand) and Analogical Modeling

    Science.gov (United States)

    Gomez, C. A.; Purdie, H.

    2015-12-01

    As global climate continues warm, mountain environments are changing, and rates of glacial retreat are unprecedented. The hydrologic implications of this rapid ice retreat and changing climate conditions have been the focus of numerous studies, but the consequent effects on the sediment cascade in valleys and tributaries has received considerably less attention. In the present study, we investigated the role of glacial recession on sediment mobilization and deposition in a mountain valley catchment at Fox Glacier, New Zealand. In particular, we analyze the role of glacier recession on the formation of sediment fans in the main valley. Emphasis was put on the role of sediment, impounded by the glacier in side tributaries, becoming rapidly available for remobilization as the glacier retreats. The method is based on field observations, and measurements using high resolution GNSS (Trimble R8 survey grade differential GNSS) and photogrammetric methods using Structure from Motion based on ground-, helicopter- and UAV- photographs. Field observations were conducted in the period 2014 - 2015, and have been complimented with analogic modeling in the laboratory, in order to comprehend the processes driving rapid fan formation. The analogic model reproduced the retreat of the glacier and the response of a tributary, with simulations for both glaciated and de-glaciated conditions. For similar hydrologic and slope parameters, the fans created after glacial retreat have shown an acceleration in their formation of up to 12 times compared to fanes created without glacial influence. Field observations within the period 2013 - 2015 of Straight Creek Fan (Fox Valley, New Zealand) have confirmed laboratory simulations, with the fan growing to a radius superior to 200 m and a valley-long width superior to 450 m. As glaciers continue to retreat, it can be expected that sediment surges will occur in affected valleys, without the requirements of other forcing like earthquake or extreme

  17. Scale effects impeding palaeoclimate reconstructions from mountain glaciers

    Science.gov (United States)

    Prinz, Rainer; Nicholson, Lindsey; Mölg, Thomas; Kaser, Georg

    2016-04-01

    Lewis Glacier on Mt. Kenya lost more than 80% of its area since its last stadial in the late 19th century (L19). Can we reconstruct climate conditions sustaining Lewis Glacier in its L19 extent? First, we optimized a physical based energy and mass balance model to the modern-day glacier extent with in situ observed climate observations. Second, from this record we constructed synthetic climate scenarios (based on coupled parameter perturbation applying a simple weather generator concept) as input for the mass balance model. These scenarios reflect the observed variability in precipitation and air temperature over recent decades, reproduce the observed mass balance variability for the modern-day glacier extent, and quantify the glacier's sensitivity to climate. Using the mass balance model as optimized for the modern-day glacier on the L19 extent, driven by climate perturbations most favourable to glaciation, results in negative mass balances. This would traditionally be interpreted to mean that even the extremes of the present-day climate are incapable of reproducing the L19 conditions. Alternatively or additionally, the modelling suggests that the L19 Lewis Glacier could be sustained if a favourable climate perturbation is applied in conjunction with a modification of the gradients used to extrapolate the climate observations over the glacier surface from those optimized for the very small modern-day glacier. Such a modification might be justifiable, where the modern-day glacier is so small that it is unlikely to generate significant microclimatological effects that would be expected for the larger L19 extent, when e.g. the glacier filled its cirque reducing long-wave emissions from surrounding terrain drastically. In a general sense this finding indicates that extracting proxy climate conditions from a particular glacier geometry, using a modelling system optimized on a dramatically different geometry, may invalidate the approach, particularly if changes in

  18. Assessing simulated ecosystem processes for climate variability research at Glacier National Park, USA

    Science.gov (United States)

    White, J.D.; Running, S.W.; Thornton, P.E.; Keane, R.E.; Ryan, K.C.; Fagre, D.B.; Key, C.H.

    1998-01-01

    Glacier National Park served as a test site for ecosystem analyses than involved a suite of integrated models embedded within a geographic information system. The goal of the exercise was to provide managers with maps that could illustrate probable shifts in vegetation, net primary production (NPP), and hydrologic responses associated with two selected climatic scenarios. The climatic scenarios were (a) a recent 12-yr record of weather data, and (b) a reconstituted set that sequentially introduced in repeated 3-yr intervals wetter-cooler, drier-warmer, and typical conditions. To extrapolate the implications of changes in ecosystem processes and resulting growth and distribution of vegetation and snowpack, the model incorporated geographic data. With underlying digital elevation maps, soil depth and texture, extrapolated climate, and current information on vegetation types and satellite-derived estimates of a leaf area indices, simulations were extended to envision how the park might look after 120 yr. The predictions of change included underlying processes affecting the availability of water and nitrogen. Considerable field data were acquired to compare with model predictions under current climatic conditions. In general, the integrated landscape models of ecosystem processes had good agreement with measured NPP, snowpack, and streamflow, but the exercise revealed the difficulty and necessity of averaging point measurements across landscapes to achieve comparable results with modeled values. Under the extremely variable climate scenario significant changes in vegetation composition and growth as well as hydrologic responses were predicted across the park. In particular, a general rise in both the upper and lower limits of treeline was predicted. These shifts would probably occur along with a variety of disturbances (fire, insect, and disease outbreaks) as predictions of physiological stress (water, nutrients, light) altered competitive relations and hydrologic

  19. Disappearance of the glacier on Mama Cotacachi: ethnoecological research and climate change in the Ecuadorian Andes

    Directory of Open Access Journals (Sweden)

    Rhoades, R.

    2008-12-01

    Full Text Available A first documented case study of a disappearing glacier in the snow capped volcano Cotacahi in Ecuador is presented with the studies belonging to the social sciences in relation to climate change and its impact on the population of the Equatorial Andes. With the use of multiple source methodology, including ethnographic analyzes, visual representations, repetitive photography, critical mapping by the local communities, longitudinal surveys, even archival research, as well as interviews to social actors and utilization of spatial data in a geographical information system (GIS. It is concluded that the documented disappearance of the glacier on the Cotacahi serves as an urgent call for action to the important dearth of social research related to global change from the ethnoecological perspective, with a cultural, local approach.

    Se presenta el primer estudio documentado de la desaparición del glaciar del nevado Cotacachi en el Ecuador, con los estudios que corresponden a las ciencias sociales en relación con el cambio climático y su impacto en la población de los Andes ecuatoriales. Mediante el uso de una metodología que incluye análisis etnográficos, representaciones visuales, fotografía repetitiva, mapeo crítico por parte de las comunidades locales, encuestas longitudinales e incluso investigación de archivos, así como también entrevistas a actores sociales, y utilización de los datos espaciales en un sistema de información geográfica (SIG. Se concluye que la desaparición documentada del glaciar del Cotacachi sirve como una llamada de atención urgente a la importante falta de investigaciones sociales relacionadas con el cambio global desde el punto de vista etnoecológico, con un enfoque cultural local.

  20. Internationally coordinated glacier monitoring - a timeline since 1894

    Science.gov (United States)

    Nussbaumer, Samuel U.; Armstrong, Richard; Fetterer, Florence; Gärtner-Roer, Isabelle; Hoelzle, Martin; Machguth, Horst; Mölg, Nico; Paul, Frank; Raup, Bruce H.; Zemp, Michael

    2016-04-01

    Changes in glaciers and ice caps provide some of the clearest evidence of climate change, with impacts on sea-level variations, regional hydrological cycles, and natural hazard situations. Therefore, glaciers have been recognized as an Essential Climate Variable (ECV). Internationally coordinated collection and distribution of standardized information about the state and change of glaciers and ice caps was initiated in 1894 and is today organized within the Global Terrestrial Network for Glaciers (GTN-G). GTN-G ensures the continuous development and adaptation of the international strategies to the long-term needs of users in science and policy. A GTN-G Steering Committee coordinates, supports and advices the operational bodies responsible for the international glacier monitoring, which are the World Glacier Monitoring Service (WGMS), the US National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. In this presentation, we trace the development of the internationally coordinated glacier monitoring since its beginning in the 19th century. Today, several online databases containing a wealth of diverse data types with different levels of detail and global coverage provide fast access to continuously updated information on glacier fluctuation and inventory data. All glacier datasets are made freely available through the respective operational bodies within GTN-G, and can be accessed through the GTN-G Global Glacier Browser (http://www.gtn-g.org/data_browser.html). Glacier inventory data (e.g., digital outlines) are available for about 180,000 glaciers (GLIMS database, RGI - Randolph Glacier Inventory, WGI - World Glacier Inventory). Glacier front variations with about 45,000 entries since the 17th century and about 6,200 glaciological and geodetic mass (volume) change observations dating back to the 19th century are available in the Fluctuations of Glaciers (FoG) database. These datasets reveal clear evidence that

  1. Modelling glacier change in the Everest region, Nepal Himalaya

    Directory of Open Access Journals (Sweden)

    J. M. Shea

    2014-10-01

    Full Text Available In this study, we apply a glacier mass balance and ice redistribution model to simulate historical and future glacier change in the Everest region of Nepal. High-resolution temperature and precipitation fields derived from gridded APHRODITE data, and validated against independent station observations from the EVK2CNR network, are used to drive the historical model from 1961 to 2007. The model is calibrated against geodetically derived estimates of net glacier mass change from 1992 to 2008, termini position of four large glaciers at the end of the calibration period, average velocities observed on selected debris-covered glaciers, and total glacierized area. We integrate field-based observations of glacier mass balance and ice thickness with remotely-sensed observations of decadal glacier change to validate the model. Between 1961 and 2007, the mean modelled volume change over the Dudh Kosi basin is −6.4 ± 1.5 km3, a decrease of 15.6% from the original estimated ice volume in 1961. Modelled glacier area change between 1961 and 2007 is −101.0 ± 11.4 km2, a decrease of approximately 20% from the initial extent. Scenarios of future climate change, based on CMIP5 RCP4.5 and RCP8.5 end members, suggest that glaciers in the Everest region will continue to lose mass through the 21st century. Glaciers in the basin are concentrated between 5000 and 6000 m of elevation, and are thus expected to be sensitive to changes in temperature and equilibrium line altitude (ELA. Glacier volume reductions between −35 to −62% are possible by 2050, and sustained temperature increases to 2100 may result in total glacier volume losses of between −73 and −96%.

  2. An aerial view of 80 years of climate-related glacier fluctuations in southeast Greenland

    DEFF Research Database (Denmark)

    Bjørk, Anders A.; Kjær, Kurt H.; Korsgaard, Niels J.;

    2012-01-01

    -terminating outlet glaciers, as well as local glaciers and ice caps, over the past 80 years. The images reveal a regional response to external forcing regardless of glacier type, terminal environment and size. Furthermore, the recent retreat was matched in its vigour during a period of warming in the 1930s......Widespread retreat of glaciers has been observed along the southeastern margin of Greenland. This retreat has been associated with increased air and ocean temperatures. However, most observations are from the satellite era; presatellite observations of Greenlandic glaciers are rare. Here we present...... a unique record that documents the frontal positions for 132 southeast Greenlandic glaciers from rediscovered historical aerial imagery beginning in the early 1930s. We combine the historical aerial images with both early and modern satellite imagery to extract frontal variations of marine- and land...

  3. Modeling and hazard mapping of complex cascading mass movement processes: the case of glacier lake 513, Carhuaz, Peru

    Science.gov (United States)

    Schneider, Demian; Huggel, Christian; García, Javier; Ludeña, Sebastian; Cochachin, Alejo

    2013-04-01

    The Cordilleras in Peru are especially vulnerable to, and affected by impacts from climate change. Local communities and cities often exist directly within the reach of major hazard potentials such as lake outburst floods (aluviones), mud-/debris flows (huaycos) or large rock-/ice avalanches. They have been repeatedly and strongly affected these regions over the last decades and since the last century, and thousands of people have been killed. One of the most recent events in the Cordillera Blanca occurred on 11 April 2010, when a rock/ice avalanche from the top of Hualcán mountain, NE of the town of Carhuaz impacted the glacier lake 513 (Laguna 513), caused displacement waves and triggered an outburst flood wave. The flow repeatedly transformed from debris flow to hyperconcentrated flow and eventually caused significant damage in Carhuaz. This event was motivation to start early warning and prevention efforts to reduce risks related to ice/rock avalanches and glacier lake outburst floods (GLOF). One of the basic components of an early warning system is the assessment, understanding and communication of relevant hazards and risks. Here we report on the methodology and results of generating GLOF related hazard maps for Carhuaz based on numerical modeling and field work. This exercise required an advanced concept and implementation of different mass movement models. Specifically, numerical models were applied for simulating avalanche flow, avalanche lake impact, displacement wave generation and lake overtopping, and eventually flow propagation of the outburst flood with changing rheology between debris flow and hyperconcentrated flows. We adopted a hazard mapping procedure slightly adjusted adjusted from guidelines developed in Switzerland and in the Andes region. A methodology has thereby been developed to translate results from numerical mass movement modeling into hazard maps. The resulting hazard map was verified and adjusted during field work. This study shows

  4. Modelling the hydrological response of debris-free and debris-covered glaciers to present climatic conditions in the semiarid Andes of central Chile

    Science.gov (United States)

    Ayala, Alvaro; Pellicciotti, Francesca; MacDonell, Shelley; McPhee, James; Vivero, Sebastián; Campos, Cristián; Egli, Pascal

    2016-04-01

    We investigate the main contributors to runoff of a 62 km2 glacierized catchment in the semiarid Andes of central Chile, where both debris-free and debris-covered glaciers are present, combining an extensive set of field measurements, remote sensing products and an advanced glacio-hydrological model (TOPKAPI-ETH). The catchment contains two debris-free glaciers reaching down to 3900 m asl (Bello and Yeso Glaciers) and one debris-covered avalanche-fed glacier reaching to 3200 m asl (Piramide Glacier). A unique dataset of field measurements collected in the ablation seasons 2013-14 and 2014-15 included four automatic weather stations, manual measurements of snow depth and debris cover thickness, discharge measurements at glaciers outlets, photographic monitoring of surface albedo as well as ablation stakes measurements and snow pits. TOPKAPI-ETH combines physically-oriented parameterizations of snow and ice ablation, gravitational distribution of snow, snow albedo evolution, glacier dynamics, runoff routing and the ablation of debris-covered ice.We obtained the first detailed estimation of mass balance and runoff contribution of debris-covered glaciers in this mountainous region. Results show that while the mass balance of Bello and Yeso Glaciers is mostly controlled by air temperature lapse rates, the mass balance of Piramide Glacier is governed by debris thickness and avalanches. In fact, gravitational distribution by avalanching on wet years plays a key role and modulates the mass balance gradient of all glaciers in the catchment and can turn local mass balance from negative to positive. This is especially the case for Piramide Glacier, which shows large amounts of snow accumulation below the steep walls surrounding its upper area. Despite the thermal insulation effect of the debris cover, the contribution to runoff from debris-free and debris-covered glaciers is similar, mainly due to elevation differences. At the catchment scale, snowmelt represents more than 60

  5. Ice flow dynamics and mass balance of Vatnajökull outlet glaciers observed by X-band SAR Data

    Science.gov (United States)

    Nagler, T.; Rott, H.; Magnússon, E.; Floricioiu, D.; Mueller, F.; Scharrer, K.

    2012-04-01

    Several outlet glaciers of the major ice caps in Iceland are affected by sub-glacial outburst floods, so-called jökulhlaups. Sources of these outbreaks are water accumulations beneath the glacier due to geothermal or volcanic activity. One component of the project NorthHydrology, carried out within the ESA STSE (Support to Science Element) programme, addresses techniques and applications of satellite data for studying drainage mechanisms and water outbreaks of sub-glacial lakes in Iceland. Such events are usually related to surface deformation and changes in ice velocities, sometimes occurring already well ahead of the peak of the flood wave. High resolution repeat pass SAR data are able to deliver spatially detailed information on surface motion and displacement, which are highly relevant for advancing the understanding of glacier hydraulics and jökulhlaup processes. A template matching technique is applied to data stacks of TerraSAR-X and Cosmo-SkyMed amplitude images acquired between summer 2008 to summer 2010 in order to study the ice dynamics and mass balance of outlet glaciers of Vatnajökull in Iceland. This technique requires distinct and stable surface features, as usually available on ice surfaces of glaciers. Main outlet glaciers, investigated in the project, are Breidamerkurjökull and Skeiderarjökull, with the fronts terminating close to the coast. The lower terminus of these glaciers exhibits significant melting during summer, and sometimes even during winter. At these glaciers in-situ data on ice velocity and surface elevation changes have been recorded at in situ GPS stations, operated by University of Iceland. The ice motion field was derived using ascending and descending repeat pass SAR images. In order to retrieve the 3D ice motion vector, effects of surface melt are taken into account by modelling the ablation. Combining maps of displacement shifts from ascending and descending passes and compensating for surface lowering due to melt, maps

  6. Linear modeling of glacier fluctuations

    NARCIS (Netherlands)

    Oerlemans, J.

    2012-01-01

    In this contribution a linear first-order differential equation is used to model glacier length fluctuations. This equation has two parameters describing the physical characteristics of a glacier: the climate sensitivity, expressing how the equilibrium glacier length depends on the climatic state, a

  7. Mass budgets of the Lambert, Mellor and Fisher Glaciers and basal fluxes beneath their flowbands on Amery Ice Shelf

    Institute of Scientific and Technical Information of China (English)

    WEN; JiaHong

    2007-01-01

    .Ann Glaciol,2002,34:269―276[14]Joughin I,Tulaczyk S.Positive mass balance of the Ross ice streams,West Antarctica,Science,2002,295:476―480[15]Rignot E.East Antarctic glaciers and ice shelves mass balance from satellite data.Ann Glaciol,2002,34:228―234[16]Liu H,Jezek K C,Li B.Development of an Antarctic digital elevation model by integrating cartographic and remotely sensed data:A geographic information system based approach,J Geophys Res,1999,104(B10):23199―23214[17]Zwally H J,Schutz B,Abdalati W,et al.ICESat's laser measurements of polar ice,atmosphere,ocean,and land.J Geodyn,2002,34 (3-4):405―445[18]Herzfeld U C,ed.Atlas of Antarctica:Topographic Maps From Geostatistical Analysis of Satellite Radar Altimeter Data.New York·Tokyo:Springer Verlag Heidelberg,2004.1―65[19]Joughin I,Padman L.Melting and freezing beneath Filchner-Ronne Ice Shelf,Antarctica.Geophys Res Lett,2003,30(9):1477[20]Vaughan D G,Bamber J L,Giovinetto M B,et al.Cooper reassessment of net surface mass balance in Antarctica.J Climate,1999,12(4):933―946[21]Giovinetto M B,Zwally H J.Spatial distribution of net surface accumulation on the Antarctic ice sheet.Ann Glaciol,2000,31:171― 178[22]Lythe M B,Vaughan D G.The BEDMAP Consortium.BEDMAP:A new ice thickness and subglacial topographic model of Antarctica.J Geophys Res,2001,106(B6):11335―11351[23]Fricker H A,Hyland G,Coleman R,et al.Digital elevation models for the Lambert Glacier-Amery Ice Shelf system,East Antarctica,from ERS-1 satellite radar altimetry.J Glaciol,2000,46(155):553―560[24]Fricker H A,Warner R C,Allison I.Mass balance of the Lambert Glacier-Amery Ice Shelf system,East Antarctica:a comparison of computed balance fluxes and measured fluxes.J Glaciol,2000,46(155):561―570[25]Jezek K C.Glaciological properties of the Antarctic ice sheet from RADARSAT-1 synthetic aperture radar imagery.Ann Glaciol,1999,29:286―290[26]Allison I.The mass budget of the Lambert Glacier drainage basin,Antarctica.J Glaciol,1979,22(87):223―235

  8. An aerial view of 80 years of climate-related glacier fluctuations in southeast Greenland

    Science.gov (United States)

    Bjørk, Anders A.; Kjær, Kurt H.; Korsgaard, Niels J.; Khan, Shfaqat A.; Kjeldsen, Kristian K.; Andresen, Camilla S.; Box, Jason E.; Larsen, Nicolaj K.; Funder, Svend

    2012-06-01

    Widespread retreat of glaciers has been observed along the southeastern margin of Greenland. This retreat has been associated with increased air and ocean temperatures. However, most observations are from the satellite era; presatellite observations of Greenlandic glaciers are rare. Here we present a unique record that documents the frontal positions for 132 southeast Greenlandic glaciers from rediscovered historical aerial imagery beginning in the early 1930s. We combine the historical aerial images with both early and modern satellite imagery to extract frontal variations of marine- and land-terminating outlet glaciers, as well as local glaciers and ice caps, over the past 80 years. The images reveal a regional response to external forcing regardless of glacier type, terminal environment and size. Furthermore, the recent retreat was matched in its vigour during a period of warming in the 1930s with comparable increases in air temperature. We show that many land-terminating glaciers underwent a more rapid retreat in the 1930s than in the 2000s, whereas marine-terminating glaciers retreated more rapidly during the recent warming.

  9. Glacier response to changing climate condition : the role of circulation variability and long-term trends over the Tibetan Plateau, China

    Energy Technology Data Exchange (ETDEWEB)

    Caidong, C.

    2008-07-01

    This study focuses on glacier response to changing climatic condition, the role of atmospheric circulation variability and long-term trends over the Tibetan Plateau (TP). In particular, this study concerns circulation regimes over the TP and related precipitation and temperature variations in Tibet Autonomous Region; modelled mass balance response of the Xibu glacier (which is situated in the Nyainqentanglha mountain range) to the circulation variability and the mass balance response to long term trends that is not directly related to circulation variability. The research was motivated by the importance of understanding present-day climate condition over the Tibetan Plateau and to understand how much of last decade's increases in temperature and glacier retreat could be linked to circulation changes and how much was due to other causes. The first paper, the focus is on using the six years of the Tropical Rainfall Monitoring Mission (TRMM) satellite data (1998 - 2005) to identify the spatial pattern of the dry season (October - April) precipitation over the TP which is small, but important for snow accumulation over the plateau. The paper outline the use of k-mean clustering as a method for finding different weather types and the precipitation variability is tried explained with physical interpretation of the associated atmospheric circulation patterns using daily reanalysis from NCEP/NCAR (1957 - 2005). The results show how the topographic effect and flow direction plays an important role in controlling the distribution of precipitation rates over the plateau. The Himalayas and Karakorum Mountain ranges act as barriers for south and south-west moist air flow and deplete the air of much of its moisture before it reaches the Plateau. In addition, when the air begin to descend on the leeward side of the mountains, they are creating a rain shadow. According to the TRMM satellite estimates average October-April Tibetan Plateau (defined as areas higher than 4,000 m

  10. Evolution of Popocatépetl volcano's glaciers in Mexico with and without volcanic activity: diagnosis from a minimal mass balance model

    Science.gov (United States)

    Ontiveros-Gonzalez, G.; Cortes Ramos, J.; Delgado Granados, H.

    2013-05-01

    This work describes the influence of eruptive activity on the evolution of the glacial cover on Popocatepetl volcano. Here, we try to answer a simple question: what had happened if this glacier had not been affected by the volcanic activity? In order to answer this question we modeled the mass balance evolution of this glacier using meteorological data and a minimal mass balance model developed for glaciers elsewhere. For this model we assumed no volcanic activity. These results were compared with measurements available for the actual situation at Popocatépetl Volcano. It was possible to separate the influence of the volcanic activity on the evolution of this glacier system considering two scenarios: one was modeled with a simulation of the mass balance where volcanic activity does not affect, and a second scenario is based on the documented studies developed around the glacial disappearance of the glaciers.

  11. Where glaciers meet water: Subaqueous melt and its relevance to glaciers in various settings

    Science.gov (United States)

    Truffer, Martin; Motyka, Roman J.

    2016-03-01

    Glacier change is ubiquitous, but the fastest and largest magnitude changes occur in glaciers that terminate in water. This includes the most rapidly retreating glaciers, and also several advancing ones, often in similar regional climate settings. Furthermore, water-terminating glaciers show a large range in morphology, particularly when ice flow into ocean water is compared to that into freshwater lakes. All water-terminating glaciers share the ability to lose significant volume of ice at the front, either through mechanical calving or direct melt from the water in contact. Here we present a review of the subaqueous melt process. We discuss the relevant physics and show how different physical settings can lead to different glacial responses. We find that subaqueous melt can be an important trigger for glacier change. It can explain many of the morphological differences, such as the existence or absence of floating tongues. Subaqueous melting is influenced by glacial runoff, which is largely a function of atmospheric conditions. This shows a tight connection between atmosphere, oceans and lakes, and glaciers. Subaqueous melt rates, even if shown to be large, should always be discussed in the context of ice supply to the glacier front to assess its overall relevance. We find that melt is often relevant to explain seasonal evolution, can be instrumental in shifting a glacier into a different dynamical regime, and often forms a large part of a glacier's mass loss. On the other hand, in some cases, melt is a small component of mass loss and does not significantly affect glacier response.

  12. Role of sub-regional variations on melting Response of Indian-Himalayan Glaciers

    Science.gov (United States)

    Tayal, S.; Hasnain, S. I.

    2010-12-01

    Glaciers play a crucial role in maintaining ecosystem stability as they act as buffers and regulate the runoff water supply from high mountains to the plains during both dry and wet spells. Retreat of Hindu Kush-Himalaya-Tibetan glaciers is one of the major environmental problems facing the south Asian and south-east Asian region. The Himalayan mountain range spans 2500 km east to west and includes diverse cultures of five countries (Afghanistan, Pakistan, India, Tibet (China), Nepal, Bhutan) and a range of weather patterns, which has been strongly affected by regional climate change. The glaciers of Indian Himalayan ranges covers an area of 19000 km2 contains over 9500 glaciers and feed major perennial river systems like Indus, Ganges, Brahmaputra, and sustain the livelihood of over 0.5 billion south Asians. Glaciers are melting fast but their response time varies from westerly nourished Kashmir Himalaya glaciers to south-west monsoon nourished Sikkim Himalaya glaciers based on regional climatic variations. Changes in mass balance of a glacier are considered as the most direct representative of the impacts of meteorological parameters on the glacier dynamic responses. A comparative study of mass balance, based on field measurements techniques is being conducted on two benchmark glaciers in the Indian Himalaya. The glaciers currently being monitored are Kolahoi glacier (340 07 - 340 12 N: 750 16 - 750 23E), Kashmir Himalaya and E.Rathong glacier (270 33 - 480 36 N: 880 06 - 880 08 E), Sikkim Himalaya. One year mass balance results (2008-2009) for both the benchmark glaciers are now available and are being presented. Mass balance for Kolahoi glacier located in sub-tropical to temperate setting and nourished by westerly system show range from -2.0 m.w.e. to -3.5 m.w.e. per annum. Whereas, the E. Rathong glacier located in tropical climatic settings and nourished by SW monsoon system show range from -2.0 m.w.e. to -5.0 m.w.e. per annum. The (2009/2010) mass balance

  13. The future sea-level rise contribution of Greenland’s glaciers and ice caps

    DEFF Research Database (Denmark)

    Machguth, H.; Rastner, P.; Bolch, T.;

    2013-01-01

    We calculate the future sea-level rise contribution from the surface mass balance of all of Greenland's glaciers and ice caps (GICs, ~90 000 km2) using a simplified energy balance model which is driven by three future climate scenarios from the regional climate models HIRHAM5, RACMO2 and MAR....... Glacier extent and surface elevation are modified during the mass balance model runs according to a glacier retreat parameterization. Mass balance and glacier surface change are both calculated on a 250 m resolution digital elevation model yielding a high level of detail and ensuring that important...... of Greenland is dominated by steadily decreasing summer mass balances. In addition we observe glaciers in the north-eastern part of Greenland changing their characteristics towards greater activity and mass turnover....

  14. Response of Modern Monsoon Temperate Glacier to Climate Change in Yulong Mountain%玉龙雪山现代季风温冰川对气候变化的响应

    Institute of Scientific and Technical Information of China (English)

    杜建括; 辛惠娟; 何元庆; 牛贺文; 蒲焘; 曹伟宏; 张涛

    2013-01-01

    Sensitive responding to climate change is the most remarkable feature of monsoon temperate glaciers,as the most direct and brightest indicator of climate change it would substantially go forward or backward by a weak change of temperature.This article selects Yulong Mountain as research region,which is the southernmost temperate glacier region at present in China and Eurasian continent.Based on field observation data and remote sensing data,combining previous research results,the response process of Yulong Mountain to climatic change is emphatically analyzed.Additionally,this article especially studies the area,shape,temperature,width,and terminus etc variation of Baishui No.1 glacier,and discusses the main causes of glacial changes.The result was as follows:1) Glaciers retreat was continuous and obvious in Yulong Mountain.Compared with 19 glaciers with total area of 11.6 km2 in 1957,6 glaciers had disappeared completely,and only 13 glaciers exist at present,with a total area of 5.30 km2 in 2001 and 4.42 km2 in 2009.The changing rate of glacier area was-1.19% in 1957-2009,which was much faster than that of other typical glacier region in China.2)Compared with 1982,the quantity of the Baishui No.lglacier crevasses increased and their scales also extend in the context of global climate change,the body of glacier had ruptured on the firn basin.A series of massive crevasses had formed on the glacier surface since 2011.Meanwhile,the.ice river/lake had appeared since 2008,glacial ablation was much intense.3) The glacier terminus elevation displayed rising state overall in 1982-2011,and the rising amplitude had increased since 1999.The retreat speed of Baishui No.1 glacier was 8.8 m/a in 1982-2011,and increased to 13.8 m/a in 1999-2011.4) The lowest temperature from glacier surface to 8 m depth at the ablation area was-0.8℃ in 1982,and rising to-0.39℃ in 2009.Rising glacier temperature caused melt speed of the ice accelerate and mass balance loss intensifying.5) The

  15. Glacier Surface Velocity Measurements from Radar Interferometry and the Principle of Mass Conservation

    DEFF Research Database (Denmark)

    Mohr, Johan Jacob; Reeh, Niels

    2002-01-01

    Presents a relation between the three glacier surface velocity components, the surface flux-divergence, glacier thickness and bottom melt and displacement. The relation can be used as an extension to the surface parallel flow assumption often used with interferometric synthetic aperture measureme...

  16. Glacier balance trends in the Kongsfjorden area, western Spitsbergen, Svalbard, in relation to the climate

    OpenAIRE

    Lefauconnier, Bernard; Hagen, Jon Ove; Børre Ørbæk, Jon; Melvold, Kjetil; Isaksson, Elisabeth

    1999-01-01

    For the last thirty years, the mean net balance of two glaciers, Austre Brøggerbreen and Midre Lovénbreen, has been -0.43 and -0.34 m of water equivalent (w.e.). respectively. The mean net balance of Kongsvegen, a tidewater glacier that has been measured since 1987, is 0.11 m w.e. The negative balances of the two first glaciers are driven by the increase in atmospheric temperature which occurred at the end of the Little Ice Age at the beginning of the century. The positive balance of Kongsveg...

  17. Mass budgets of the Lambert, Mellor and Fisher Glaciers and basal fluxes beneath their flowbands on Amery Ice Shelf

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We used in situ measurements and remote-sensing data sets to evaluate the mass budgets of the Lambert,Mellor and Fisher Glaciers and the basal melting and freezing rates beneath their flowbands on the Amery Ice Shelf.Our findings show the Lambert and Mellor Glaciers upstream of the ANARE Lambert Glacier Basin (LGB) traverse may have positive imbalances of 3.9±2.1 Gt a-1 and 2.1±2.4 Gt a-1,respectively,while the Fisher Glacier is approximately in balance.The upstream region as a whole has a positive imbalance of 5.9±4.9 Gt a-1.The three same glaciers downstream of the ANARE LGB traverse line are in negative imbalance,where the whole downstream region has a negative imbalance of -8.5±5.8 Gt a-1.Overall the mass budgets of the Lambert,Mellor,and Fisher Glaciers are close to balance,and the collective three-glacier system is also nearly in balance with a mass budget of -2.6±6.5 Gt a-1.The significant positive imbalances for the interior basin upstream of the ice-movement stations established in the early 1970s (GL line) reported previously are possibly due to an overestimate of the total accumulation and an underestimate of the ice flux through the GL line.The mean melting rate is -23.0±3.5 m ice a-1 near the southern grounding line,which decreases rapidly downstream,and transitions to refreezing at around 300 km from the southern extremity of the Amery Ice Shelf.Freezing rates along the flowbands are around 0.5±0.1 to 1.5±0.2 m ice a-1.The percentage of ice lost from the interior by basal melting beneath the flowbands is about 80%±5%.The total basal melting and refreezing beneath the three flowbands is 50.3±7.5 Gt ice a-1 and 7.0±1.1 Gt ice a-1,respectively.We find a much larger total basal melting and net melting than the results for the whole Amery Ice Shelf derived from previous modeling and oceanographic measurements.

  18. The Little Ice Age: glacier variations and climate since AD 1250 [abstract

    OpenAIRE

    Porter, Stephen C.

    1996-01-01

    EXTRACT (SEE PDF FOR FULL ABSTRACT): During the past hundred years, mountain glaciers throughout the world have retreated significantly from moraines built during the previous several centuries. In the 1930s, Francois Matthes of the U.S. Geological Survey concluded that the moraines represent the greatest advances of glaciers since the end of the last glacial age, some 10,000 years earlier, and informally referred to this late Holocene interval of expanded ice cover as the Little Ice Age.

  19. Investigating ice cliff evolution and contribution to glacier mass-balance using a physically-based dynamic model

    Science.gov (United States)

    Buri, Pascal; Miles, Evan; Ragettli, Silvan; Brun, Fanny; Steiner, Jakob; Pellicciotti, Francesca

    2016-04-01

    Supraglacial cliffs are a surface feature typical of debris-covered glaciers, affecting surface evolution, glacier downwasting and mass balance by providing a direct ice-atmosphere interface. As a result, melt rates can be very high and ice cliffs may account for a significant portion of the total glacier mass loss. However, their contribution to glacier mass balance has rarely been quantified through physically-based models. Most cliff energy balance models are point scale models which calculate energy fluxes at individual cliff locations. Results from the only grid based model to date accurately reflect energy fluxes and cliff melt, but modelled backwasting patterns are in some cases unrealistic, as the distribution of melt rates would lead to progressive shallowing and disappearance of cliffs. Based on a unique multitemporal dataset of cliff topography and backwasting obtained from high-resolution terrestrial and aerial Structure-from-Motion analysis on Lirung Glacier in Nepal, it is apparent that cliffs exhibit a range of behaviours but most do not rapidly disappear. The patterns of evolution cannot be explained satisfactorily by atmospheric melt alone, and are moderated by the presence of supraglacial ponds at the base of cliffs and by cliff reburial with debris. Here, we document the distinct patterns of evolution including disappearance, growth and stability. We then use these observations to improve the grid-based energy balance model, implementing periodic updates of the cliff geometry resulting from modelled melt perpendicular to the ice surface. Based on a slope threshold, pixels can be reburied by debris or become debris-free. The effect of ponds are taken into account through enhanced melt rates in horizontal direction on pixels selected based on an algorithm considering distance to the water surface, slope and lake level. We use the dynamic model to first study the evolution of selected cliffs for which accurate, high resolution DEMs are available

  20. A data set of worldwide glacier fluctuations

    OpenAIRE

    P. W. Leclercq; Oerlemans, J.; H. J. Basagic; I. Bushueva; Cook, A. J.; Le Bris, R.

    2014-01-01

    Glacier fluctuations contribute to variations in sea level and historical glacier length fluctuations are natural indicators of past climate change. To study these subjects, longterm information of glacier change is needed. In this paper we present a data set of global long-term glacier length fluctuations. The data set is a compilation of available information on changes in glacier length worldwide, including both measured and reconstructed glacier length fluctuations. All 471 length series ...

  1. Glacier Ecosystems of Himalaya

    Science.gov (United States)

    Kohshima, S.; Yoshimura, Y.; Takeuchi, N.; Segawa, T.; Uetake, J.

    2012-12-01

    Biological activity on glaciers has been believed to be extremely limited. However, we found various biotic communities specialized to the glacier environment in various part of the world, such as Himalaya, Patagonia and Alaska. Some of these glacier hosted biotic communities including various cold-tolerant insects, annelids and copepods that were living in the glacier by feeding on algae and bacteria growing in the snow and ice. Thus, the glaciers are simple and relatively closed ecosystems sustained by the primary production in the snow and ice. In this presentation, we will briefly introduce glacier ecosystems in Himalaya; ecology and behavior of glacier animals, altitudinal zonation of snow algal communities, and the structure of their habitats in the glacier. Since the microorganisms growing on the glacier surface are stored in the glacial strata every year, ice-core samples contain many layers with these microorganisms. We showed that the snow algae in the ice-core are useful for ice core dating and could be new environmental signals for the studies on past environment using ice cores. These microorganisms in the ice core will be important especially in the studies of ice core from the glaciers of warmer regions, in which chemical and isotopic contents are often heavily disturbed by melt water percolation. Blooms of algae and bacteria on the glacier can reduce the surface albedo and significantly affect the glacier melting. For example, the surface albedo of some Himalayan glaciers was significantly reduced by a large amount of dark-colored biogenic material (cryoconite) derived from snow algae and bacteria. It increased the melting rates of the surfaces by as much as three-fold. Thus, it was suggested that the microbial activity on the glacier could affect the mass balance and fluctuation of the glaciers.

  2. Processes governing the mass balance of Chhota Shigri Glacier (western Himalaya, India) assessed by point-scale surface energy balance measurements

    OpenAIRE

    Azam, M. F.; P. Wagnon; Vincent, C; Ramanathan, Al.; Favier, V.; Mandal, A; Pottakkal, J. G.

    2014-01-01

    Some recent studies revealed that Himalayan glaciers were shrinking at an accelerated rate since the beginning of the 21st century. However, the climatic causes for this shrinkage remain unclear given that surface energy balance studies are almost nonexistent in this region. In this study, a point-scale surface energy balance analysis was performed using in situ meteorological data from the ablation zone of Chhota Shigri Glacier over two separate periods (August 2012 to February 2013 and July...

  3. Processes governing the mass balance of Chhota Shigri Glacier (Western Himalaya, India) assessed by point-scale surface energy balance measurements

    OpenAIRE

    Azam, M. F.; P. Wagnon; Vincent, C; AL. Ramanathan; Mandal, A; Pottakkal, J. G.

    2014-01-01

    Recent studies revealed that Himalayan glaciers have been shrinking at an accelerated rate since the beginning of the 21st century. However the climatic causes for this shrinkage remain unclear given that surface energy balance studies are almost nonexistent in this region. In this study, a point-scale surface energy balance analysis was performed using in-situ meteorological data from the ablation zone of Chhota Shigri Glacier over two separate periods (Aug...

  4. Mass balance, meteorological, and runoff measurements at South Cascade Glacier, Washington, 1992 balance year

    Science.gov (United States)

    Krimmel, R.M.

    1993-01-01

    Values of winter snow accumulation and summer snow, firn, and ice ablation were measured at South Cascade Glacier, WA, to determine the winter and net balance for the 1992 balance year. The 1992 winter balance, averaged over the glacier, was 1.91 m, and the net balance was -2.01 m. This extremely negative balance continued a trend of negative balance years beginning in 1977. Air temperature (at 1,615 m and 1,867 m), barometric pressure, precipitation, and runoff from this glacier basin and an adjacent non-glacierized basin were also continuously measured. This report makes all these data, in tabular, graphical, and machine-readable forms, available to users.

  5. Melting beneath Greenland outlet glaciers and ice streams

    Science.gov (United States)

    Alexander, David; Perrette, Mahé; Beckmann, Johanna

    2015-04-01

    Basal melting of fast-flowing Greenland outlet glaciers and ice streams due to frictional heating at the ice-bed interface contributes significantly to total glacier mass balance and subglacial meltwater flux, yet modelling this basal melt process in Greenland has received minimal research attention. A one-dimensional dynamic ice-flow model is calibrated to the present day longitudinal profiles of 10 major Greenland outlet glaciers and ice streams (including the Jakobshavn Isbrae, Petermann Glacier and Helheim Glacier) and is validated against published ice flow and surface elevation measurements. Along each longitudinal profile, basal melt is calculated as a function of ice flow velocity and basal shear stress. The basal shear stress is dependent on the effective pressure (difference between ice overburden pressure and water pressure), basal roughness and a sliding parametrization. Model output indicates that where outlet glaciers and ice streams terminate into the ocean with either a small floating ice tongue or no floating tongue whatsoever, the proportion of basal melt to total melt (surface, basal and submarine melt) is 5-10% (e.g. Jakobshavn Isbrae; Daugaard-Jensen Glacier). This proportion is, however, negligible where larger ice tongues lose mass mostly by submarine melt (~1%; e.g. Nioghalvfjerdsfjorden Glacier). Modelled basal melt is highest immediately upvalley of the grounding line, with contributions typically up to 20-40% of the total melt for slippery beds and up to 30-70% for resistant beds. Additionally, modelled grounding line and calving front migration inland for all outlet glaciers and ice streams of hundreds of metres to several kilometres occurs. Including basal melt due to frictional heating in outlet glacier and ice stream models is important for more accurately modelling mass balance and subglacial meltwater flux, and therefore, more accurately modelling outlet glacier and ice stream dynamics and responses to future climate change.

  6. A data set of worldwide glacier fluctuations

    NARCIS (Netherlands)

    Leclercq, P.W.; Oerlemans, J.; Basagic, H.J.; Bushueva, I.; Cook, A.J.; Le Bris, R.

    2014-01-01

    Glacier fluctuations contribute to variations in sea level and historical glacier length fluctuations are natural indicators of past climate change. To study these subjects, longterm information of glacier change is needed. In this paper we present a data set of global long-term glacier length fluct

  7. Global Terrestrial Network for Glaciers: Databases and Web interfaces

    Science.gov (United States)

    Raup, B.; Armstrong, R.; Fetterer, F.; Gartner-Roer, I.; Haeberli, W.; Hoelzle, M.; Khalsa, S. J. S.; Nussbaumer, S.; Weaver, R.; Zemp, M.

    2012-04-01

    The Global Terrestrial Network for Glaciers (GTN-G) is an umbrella organization with links to the Global Climate Observing System (GCOS), Global Terrestrial Observing System (GTOS), and UNESCO (all organizations under the United Nations), for the curation of several glacier-related databases. It is composed of the World Glacier Monitoring Service (WGMS), the U.S. National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. The glacier databases include the World Glacier Inventory (WGI), the GLIMS Glacier Database, the Glacier Photograph Collection at NSIDC, and the Fluctuations of Glaciers (FoG) and Mass Balance databases at WGMS. We are working toward increased interoperability between these related databases. For example, the Web interface to the GLIMS Glacier Database has also included queryable layers for the WGI and FoG databases since 2008. To improve this further, we have produced a new GTN-G web portal (http://www.gtn-g.org/), which includes a glacier metadata browsing application. This web application allows the browsing of the metadata behind the main GTN-G databases, as well as querying the metadata in order to get to the source, no matter which database holds the data in question. A new glacier inventory, called the Randolph Glacier Inventory 1.0, has recently been compiled. This compilation, which includes glacier outlines that do not have the attributes or IDs or links to other data like the GLIMS data do, was motivated by the tight deadline schedule of the sea level chapter of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Now served from the GLIMS website (http://glims.org/), it is designed to serve that narrowly focused research goal in the near term, and in the longer term will be incorporated into the multi-temporal glacier database of GLIMS. For the required merging of large sets of glacier outlines and association of proper IDs that tie together outlines

  8. Spatial debris-cover effect on the maritime glaciers of Mount Gongga, south-eastern Tibetan Plateau

    Science.gov (United States)

    Zhang, Y.; Hirabayashi, Y.; Fujita, K.; Liu, S.; Liu, Q.

    2013-06-01

    The Tibetan Plateau and surroundings contain a large number of debris-covered glaciers, on which debris cover affects glacier response to climate change by altering ice melting rates and spatial patterns of mass loss. Insufficient spatial distribution of debris thickness data makes it difficult to analyze regional debris-cover effects. Mount Gongga glaciers, maritime glaciers in the south-eastern Tibetan Plateau, are characterized by a substantial reduction in glacier length and ice mass in recent decades. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)-derived thermal property of the debris layer reveals that 68% of the glaciers have extensive mantles of supraglacial debris in their ablation zones, in which the proportion of debris cover to total glacier area varies from 1.74% to 53.0%. Using a surface energy-mass balance model accounting for the debris-cover effect applied at a regional scale, we find that although the presence of supraglacial debris has a significant insulating effect on heavily debris-covered glaciers, it accelerates ice melting on ~ 10.2% of the total ablation area and produces rapid wastage of ~ 25% of the debris-covered glaciers, resulting in the similar mass losses between debris-covered and debris-free glaciers. Widespread debris cover also facilitates the development of active terminus regions. Regional differences in the debris-cover effect are apparent, highlighting the importance of debris cover for understanding glacier status and hydrology in both the Tibetan Plateau and other mountain ranges around the world.

  9. Changes in glacier extent and surface elevations in the Depuchangdake region of northwestern Tibet, China

    Science.gov (United States)

    Li, Zhiguo; Tian, Lide; Wu, Hongbo; Wang, Weicai; Zhang, Shuhong; Zhang, Jingjing; Li, Xuexin

    2016-01-01

    Remote sensing data, including those from Landsat Thematic Mapper/Enhanced Thematic Mapper Plus (TM/ETM +), the Shuttle Radar Topography Mission Digital Elevation Model (SRTM4.1 DEM), and the Geoscience Laser Altimeter System Ice, Cloud, and Land Elevation Satellite (Glas/ICESat), show that from 1991 to 2013 the glacier area in the Depuchangdake region of northwestern Tibet decreased from 409 to 393 km2, an overall loss of 16 km2, or 3.9% of the entire 1991 glacial area. The mean glacier-thinning rate was - 0.40 ± 0.16 m equivalent height of water per year (w.e./yr), equating to a glacier mass balance of - 0.16 ± 0.07 km3 w.e./yr. Total mass loss from 2003 to 2009 was - 1.13 ± 0.46 km3. Glacier retreat likely reflects increases in annual total radiation, annual positive degree days, and maximum temperature, with concurrent increases in precipitation insufficient to replenish glacial mass loss. The rate of glacier retreat in Depuchangdake is less than that for Himalayan glaciers in Indian monsoon-dominated areas, but greater than that for Karakoram glaciers in mid-latitude westerly-dominated areas. Glacier type, climate zone, and climate change all impact on the differing degrees of long-term regional glacial change rate; however, special glacier distribution forms can sometimes lead to exceptional circumstances.

  10. Long-term linkages between glaciers, permafrost and hydrology at two glacierized watersheds in Alaska

    Science.gov (United States)

    Gaedeke, A.; Liljedahl, A. K.; Gatesman, T.; Campbell, S. W.; Hock, R.; Oneel, S.

    2015-12-01

    Climate warming is expected to have considerable impact on the regional water balance of high latitude Arctic and sub-Arctic glacerized watersheds. In this study we combine field observations and the physically based Water Balance Simulation Model WaSiM to refine our understanding of the linkages between glaciers, permafrost and hydrology at two nearby basins with contrasting precipitation regimes: Jarvis Cr. watershed (630 km2) on the north (rain-shadow) side of Eastern Alaska Range and the south facing Phelan Cr. (32 km2), which include the US Geological Survey benchmark site Gulkana Glacier. Both are characterized by a semi-arid climate and are sub-watersheds of the Tanana River basin (12,000 km2). Our research questions include: How has glacier water storage and release varied in the past and how are they expected to change in the future? And what are the subsequent effects on lowland runoff and regional groundwater recharge? Our analyses show i) an increase in air temperature and summer warmth index (the sum of all mean monthly air temperature above 0 °C) in recent decades and ii) a continued negative glacier mass balance. Our findings suggest that, on the larger spatial scale (Tanana River basin), the reduced glacier coverage and increased glacier wastage has, in combination with limited changes in precipitation, lead to (i) increased mean annual and (ii) late winter (March) runoff. We postulate that this is due to increased groundwater recharge, which has been fueled by the 20% reduction in glacier coverage of the Tanana River basin. Here we aim to assess the combined effect of climate change, glacier shrinkage and thawing permafrost on the regional sub-arctic mountain- to lowland hydrologic system, which may transition into a regime with less surface and more subsurface water availability.

  11. Glaciers dominate eustatic sea-level rise in the 21st century

    Science.gov (United States)

    Meier, Mark Frederick; Dyurgerov, M.B.; Rick, Ursula K.; Pfeffer, William Tad; Anderson, Suzanne P.; Glazovsky, Andrey F.

    2007-01-01

    Ice loss to the sea currently accounts for virtually all of the sea-level rise that is not attributable to ocean warming, and about 60% of the ice loss is from glaciers and ice caps rather than from the two ice sheets. The contribution of these smaller glaciers has accelerated over the past decade, in part due to marked thinning and retreat of marine-terminating glaciers associated with a dynamic instability that is generally not considered in mass-balance and climate modeling. This acceleration of glacier melt may cause 0.1 to 0.25 meter of additional sea-level rise by 2100.

  12. Water, Ice, and Meteorological Measurements at Xiao Dongkemadi Glacier, Central Tibetan Plateau, Balance Years from 2008 to 2011

    Science.gov (United States)

    Xiaobo, He; Baisheng, Ye; Yongjian, Ding; Jian, Zhang

    2013-04-01

    The glaciers on Tibetan Plateau play an important role in the catchment hydrology and climatology of this region. However, our knowledge with respect to water circulation in this remote area is scarce. Xiao Dongkemadi Glacier (XDG) is located near Tanggula Pass (the highest point on the Lanzhou-Lhasa road 5231ma.s.l.), central Tibetan Plateau (33°04'N, 92°04'E). Here, glacier mass balance and runoff directly reflects the glacier's response to local climate change, and glacier changes on the Tibetan Plateau strongly influence human welfare since water supplies in this arid/semi-arid region are predominantly from glacier melt. Due to its remote location, the mass balance of XDG has been monitored discontinuously since 1988 by the direct glaciological method. Recently, a more complete and fine-grained glacier monitoring system has been established on the cap of XDG, and is expected to make further contributions to research on the change of the cryospheric and climatic environment in the area. Winter snow accumulation and summer snow and ice ablation were measured at XDG, to estimate glacier mass-balance quantities for balance years from 2008 to 2011. Runoff from the basin containing the glacier and from an adjacent nonglacierized basin was gaged during all or parts of water years from 2008 and 2011. Air temperature, wind speed, precipitation, and incoming solar radiation were measured at selected locations on and near the glacier.

  13. 100 Years of Glacier Photographs: Available Online at the National Snow and Ice Data Center

    Science.gov (United States)

    Ballagh, L. M.; Wolfe, J.; Wang, I.; Casey, A.; Fetterer, F.

    2004-12-01

    Historic glacier photographs can be used to study fluctuations in glacier extent over time in response to climate change. Researchers can also use the photographs to approximate changes in glacier terminus location and mass balance. The "Glacier Photograph Collection" at the National Snow and Ice Data Center (NSIDC) contains approximately 5,000 photographs, including both aerial and terrestrial images. NSIDC received funding from the NOAA Climate Database Modernization Program (CDMP) to digitize a portion of the photographs and make an Online Glacier Photograph Database available. The CDMP's primary objective is to preserve climate data and facilitate access to the data. Although digitizing images is expensive, long-term data preservation is a major benefit. When historic photographs are stored on film, images can easily be scratched or damaged. Scanning the images and having them online makes browsing images easier for users. At present, there are 1,313 glacier photographs available online. Additional photos and metadata are being added. The Online Glacier Photograph Database will date from 1883 to 1995, totaling nearly 3,000 photographs available as high resolution TIFF images and lower resolution reference images and thumbnails by the end of 2004. Maintaining accurate metadata records for each photograph is very important. The database is searchable by various fields, including photographer name, photograph date, glacier name, glacier coordinates, state/province, and keyword.

  14. Glacial lakes amplify glacier recession in the central Himalaya

    Science.gov (United States)

    King, Owen; Quincey, Duncan; Carrivick, Jonathan; Rowan, Ann

    2016-04-01

    The high altitude and high latitude regions of the world are amongst those which react most intensely to climatic change. Across the Himalaya glacier mass balance is predominantly negative. The spatial and temporal complexity associated with this ice loss across different glacier clusters is poorly documented however, and our understanding of the processes driving change is limited. Here, we look at the spatial variability of glacier hypsometry and glacial mass loss from three catchments in the central Himalaya; the Dudh Koshi basin, Tama Koshi basin and an adjoining section of the Tibetan Plateau. ASTER and SETSM digital elevation models (2014/15), corrected for elevation dependant biases, co-registration errors and along or cross track tilts, are differenced from Shuttle Radar Topographic Mission (SRTM) data (2000) to yield surface lowering estimates. Landsat data and a hypsometric index (HI), a classification scheme used to group glaciers of similar hypsometry, are used to examine the distribution of glacier area with altitude in each catchment. Surface lowering rates of >3 m/yr can be detected on some glaciers, generally around the clean-ice/debris-cover boundary, where dark but thin surface deposits are likely to enhance ablation. More generally, surface lowering rates of around 1 m/yr are more pervasive, except around the terminus areas of most glaciers, emphasising the influence of a thick debris cover on ice melt. Surface lowering is only concentrated at glacier termini where glacial lakes have developed, where surface lowering rates are commonly greater than 2.5 m/yr. The three catchments show contrasting hypsometric distributions, which is likely to impact their future response to climatic changes. Glaciers of the Dudh Koshi basin store large volumes of ice at low elevation (HI > 1.5) in long, debris covered tongues, although their altitudinal range is greatest given the height of mountain peaks in the catchment. In contrast, glaciers of the Tama Koshi

  15. Assessing the potential contribution of blowing snow to the mass balance of glaciers in the Cariboo Mountains of British Columbia, Canada

    Science.gov (United States)

    Yadghar, A.; Ainslie, B.; Jackson, P. L.; Dery, S. J.

    2009-05-01

    The difference between snow accumulation and ice ablation determines the mass balance of glaciers, with snowfall as the dominant input. However, blowing snow is another important term in glacier mass balance. Blowing snow occurs when loose particles of snow at the surface are entrained by winds exceeding a certain threshold for transport. The role of blowing snow in the surface mass balance of glaciers in the Cariboo Mountains (the northern extension of the Columbia Mountains) of British Columbia, Canada is assessed in this study. The regional atmospheric modeling system (RAMS) model is used to simulate several case studies of blowing snow in the region of interest. The simulations are validated with meteorological data from a mesoscale network (mesonet) of high-elevation automatic weather stations (AWSs) entitled the Cariboo Alpine Mesonet (CAMnet) that has been developed in the region since 2006. The mass divergence (convergence) fields from the RAMS simulations provide an indication of the blowing snow erosion (accumulation) areas. These are then compared with the spatial distribution of glaciers in the Cariboo Mountains. Our results suggest that snow drift may contribute significantly to the mass budget of glaciers in the region.

  16. Glaciers of Asia

    Science.gov (United States)

    Williams, Richard S., Jr.; Ferrigno, Jane G.

    2010-01-01

    systems of the world including the Himalaya, Karakorum, Tien Shan and Altay mountain ranges. The glaciers are widely scattered and cover an area of about 59,425 km2. The mountain glaciers may be classified as maritime, subcontinental or extreme continental. In Afghanistan, more than 3,000 small glaciers occur in the Hindu Kush and Pamir mountains. Most glaciers occur on north-facing slopes shaded by mountain peaks and on east and southeast slopes that are shaded by monsoon clouds. The glaciers provide vital water resources to the region and cover an area of about 2,700 km2. Glaciers of northern Pakistan are some of the largest and longest mid-latitude glaciers on Earth. They are located in the Hindu Kush, Himalaya, and Karakoram mountains and cover an area of about 15,000 km2. Glaciers here are important for their role in providing water resources and their hazard potential. The glaciers in India are located in the Himalaya and cover about 8,500 km2. The Himalaya contains one of the largest reservoirs of snow and ice outside the polar regions. The glaciers are a major source of fresh water and supply meltwater to all the rivers in northern India, thereby affecting the quality of life of millions of people. In Nepal, the glaciers are located in the Himalaya as individual glaciers; the glacierized area covers about 5,324 km2. The region is the highest mountainous region on Earth and includes the Mt. Everest region. Glaciers in the Bhutan Himalaya have a total area of about 1,317 km2. Many recent glacier studies are focused on glacier lakes that have the potential of generating dangerous glacier lake outburst floods. Research on the glaciers of the middle-latitude, high-mountain glaciers of Asia has also focused on the information contained in the ice cores from the glaciers. This information helps in the reconstruction of paleoclimatic records, and the computer modeling of global climate change.

  17. Modeling sensitivity study of the possible impact of snow and glaciers developing over Tibetan Plateau on Holocene African-Asian summer monsoon climate

    Directory of Open Access Journals (Sweden)

    L. Jin

    2008-12-01

    Full Text Available The impacts of various scenarios of snow and glaciers developing over the Tibetan Plateau on climate change in Afro-Asian monsoon region and other regions during the Holocene (9 kyr BP–0 kyr BP are studied by using the coupled climate model of intermediate complexity, CLIMBER-2. The simulations show that the imposed snow and glaciers over the Tibetan Plateau in the mid-Holocene induce global summer temperature decreases, especially in the northern parts of Europe, Asia, and North America. At the same time, with the imposed snow and glaciers, summer precipitation decreases strongly in North Africa and South Asia as well as northeastern China, while it increases in Southeast Asia and the Mediterranean. For the whole period of Holocene (9 kyr BP–0 kyr BP, the response of vegetation cover to the imposed snow and glaciers cover over the Tibetan Plateau is not synchronous in South Asia and in North Africa, showing an earlier and a more rapid decrease in vegetation cover in North Africa from 9 to 6 kyr BP while it has only minor influence on that in South Asia until 5 kyr BP. Imposed gradually increased snow and glacier cover over the Tibetan Plateau causes temperature increases in South Asia and it decreases in North Africa and Southeast Asia during 6 kyr BP to 0 kyr BP. The precipitation decreases rapidly in North Africa and South Asia while it decreases slowly or unchanged during 6 kyr BP to 0 kyr BP with imposed snow and glacier cover over the Tibetan Plateau. The different scenarios of snow and glacier developing over the Tibetan Plateau would result in differences in variation of temperature, precipitation and vegetation cover in North Africa, South Asia and Southeast Asia. The model results show that the response of climate change in African-Asian monsoon region to snow and glacier cover over the Tibetan Plateau is in the way that the snow and glaciers amplify the effect of vegetation feedback and, hence, further amplify orbital forcing.

  18. Contribution of snow and glacier melt to discharge for highly glacierised catchments in Norway

    Science.gov (United States)

    Engelhardt, M.; Schuler, T. V.; Andreassen, L. M.

    2014-02-01

    Glacierised catchments show a discharge regime that is strongly influenced by snow and glacier meltwaters. In this study, we modelled the mass balance and discharge rates for three highly glacierised catchments (>50% glacier cover) in western Norway over the period 1961-2012. The spatial pattern of the catchments follows a gradient in climate continentality from west to east. The model input were gridded temperature and precipitation values from seNorge (http://senorge.no) which are available at daily resolution. The model accounted for accumulation of snow, transformation of snow to firn and ice, evaporation and melt. Calibration and validation were performed for each catchment based on measurements of seasonal glacier mass balances and daily discharge rates, as additional validation data served daily melt rates from sonic rangers located in the ablation zones of two of the glaciers. The discharge sources snowmelt, glacier melt and rain were analysed with respect to spatial variations and temporal evolution. Model simulations reveal an increase in the relative contribution from glacier melt to total discharge for the three catchments from less than 10% in the early 1990s to 15-30% in the late 2000s. The decline in precipitation by 10-20% in the same period was therefore overcompensated, resulting in an increase in annual discharge by 5-20%. Annual discharge sums and annual glacier melt are most strongly correlated with annual and winter precipitation at the most maritime glacier and, with increased climate continentality, variations in both glacier melt contribution and annual discharge are becoming more strongly correlated with variations in summer temperatures. Therefore, glaciers in more continental climates are especially vulnerable to decrease in both annual and summer discharge with continued rise in summer temperatures and subsequent decrease in glacier extent. This may lead to significant changes to the discharge regime, with increase during spring but

  19. Balanced conditions or slight mass gain of glaciers in the Lahaul and Spiti region (northern India, Himalaya during the nineties preceded recent mass loss

    Directory of Open Access Journals (Sweden)

    C. Vincent

    2013-04-01

    Full Text Available The volume change of the Chhota Shigri Glacier (India, 32° 20 N, 77° 30' E between 1988 and 2010 has been determined using in situ geodetic measurements. This glacier has experienced only a slight mass loss between 1988 and 2010 (−3.8 ± 2.0 m w.e. (water equivalent corresponding to −0.17 ± 0.09 m w.e. yr−1. Using satellite digital elevation models (DEM differencing and field measurements, we measure a negative mass balance (MB between 1999 and 2010 (−4.8 ± 1.8 m w.e. corresponding to −0.44 ± 0.16 m w.e. yr−1. Thus, we deduce a slightly positive or near-zero MB between 1988 and 1999 (+1.0 ± 2.7 m w.e. corresponding to +0.09 ± 0.24 m w.e. yr−1. Furthermore, satellite DEM differencing reveals that the MB of the Chhota Shigri Glacier (−0.39 ± 0.15 m w.e. yr−1 has been only slightly less negative than the MB of a 2110 km2 glaciarized area in the Lahaul and Spiti region (−0.44 ± 0.09 m w.e. yr−1 during 1999−2011. Hence, we conclude that the ice wastage is probably moderate in this region over the last 22 yr, with near equilibrium conditions during the nineties, and an ice mass loss after. The turning point from balanced to negative mass budget is not known but lies probably in the late nineties and at the latest in 1999. This positive or near-zero MB for Chhota Shigri Glacier (and probably for the surrounding glaciers of the Lahaul and Spiti region during at least part of the 1990s contrasts with a recent compilation of MB data in the Himalayan range that indicated ice wastage since 1975. However, in agreement with this compilation, we confirm more negative balances since the beginning of the 21st century.

  20. Glaciers and society

    DEFF Research Database (Denmark)

    Gagné, Karine; Rasmussen, Mattias Borg; Orlove, Ben

    2014-01-01

    As icons of a world set in motion by human action, glaciers are often highlighted as quintessential evidences of global climate change. Although there is a general agreement among scientists that glaciers around the world are receding, much of the discussions on the subject tend to be oriented...... of attribution, perception, and valuation by local and distant actors. As a consequence, as they recede, glaciers often become the loci of interactions between actors of various scales. But besides melting, glaciers also transform from being objects of local to national and global concern. This is particularly...... true when esthetic and economic values are assigned to glaciers. Real and perceived changes in the form, reach and out-flow of water impact the local populations, and shape the kinds of action undertaken by communities, local actors, state authorities, and international organizations. The paper...

  1. Toward hydro-social modeling: Merging human variables and the social sciences with climate-glacier runoff models (Santa River, Peru)

    Science.gov (United States)

    Carey, Mark; Baraer, Michel; Mark, Bryan G.; French, Adam; Bury, Jeffrey; Young, Kenneth R.; McKenzie, Jeffrey M.

    2014-10-01

    Glacier shrinkage caused by climate change is likely to trigger diminished and less consistent stream flow in glacier-fed watersheds worldwide. To understand, model, and adapt to these climate-glacier-water changes, it is vital to integrate the analysis of both water availability (the domain of hydrologists) and water use (the focus for social scientists). Drawn from a case study of the Santa River watershed below Peru’s glaciated Cordillera Blanca mountain range, this paper provides a holistic hydro-social framework that identifies five major human variables critical to hydrological modeling because these forces have profoundly influenced water use over the last 60 years: (1) political agendas and economic development; (2) governance: laws and institutions; (3) technology and engineering; (4) land and resource use; and (5) societal responses. Notable shifts in Santa River water use-including major expansions in hydroelectricity generation, large-scale irrigation projects, and other land and resource-use practices-did not necessarily stem from changing glacier runoff or hydrologic shifts, but rather from these human variables. Ultimately, then, water usage is not predictable based on water availability alone. Glacier runoff conforms to certain expected trends predicted by models of progressively reduced glacier storage. However, societal forces establish the legal, economic, political, cultural, and social drivers that actually shape water usage patterns via human modification of watershed dynamics. This hydro-social framework has widespread implications for hydrological modeling in glaciated watersheds from the Andes and Alps to the Himalaya and Tien Shan, as well as for the development of climate change adaptation plans.

  2. Towards a process-based understanding of Holocene polar climate change. Using glacier-fed lake sediments from Arctic Svalbard and Antarctic South Georgia

    OpenAIRE

    Bilt, Willem van der

    2016-01-01

    Earth`s polar regions are undergoing dramatic changes due to ongoing climate change as demonstrated by increasing temperatures, collapsing ice shelves, Arctic sea ice loss and rapid glacier retreat. Driving an accelerating rise in global sea level, this amplified regional response may have devastating global socio-economic consequences in the foreseeable future. Yet the causes and range of polar climate variability remain poorly understood as observational records are short and fragmentary, w...

  3. Rapid Late Holocene glacier fluctuations reconstructed from South Georgia lake sediments using novel analytical and numerical techniques

    Science.gov (United States)

    van der Bilt, Willem; Bakke, Jostein; Werner, Johannes; Paasche, Øyvind; Rosqvist, Gunhild

    2016-04-01

    The collapse of ice shelves, rapidly retreating glaciers and a dramatic recent temperature increase show that Southern Ocean climate is rapidly shifting. Also, instrumental and modelling data demonstrate transient interactions between oceanic and atmospheric forcings as well as climatic teleconnections with lower-latitude regions. Yet beyond the instrumental period, a lack of proxy climate timeseries impedes our understanding of Southern Ocean climate. Also, available records often lack the resolution and chronological control required to resolve rapid climate shifts like those observed at present. Alpine glaciers are found on most Southern Ocean islands and quickly respond to shifts in climate through changes in mass balance. Attendant changes in glacier size drive variations in the production of rock flour, the suspended product of glacial erosion. This climate response may be captured by downstream distal glacier-fed lakes, continuously recording glacier history. Sediment records from such lakes are considered prime sources for paleoclimate reconstructions. Here, we present the first reconstruction of Late Holocene glacier variability from the island of South Georgia. Using a toolbox of advanced physical, geochemical (XRF) and magnetic proxies, in combination with state-of-the-art numerical techniques, we fingerprinted a glacier signal from glacier-fed lake sediments. This lacustrine sediment signal was subsequently calibrated against mapped glacier extent with the help of geomorphological moraine evidence and remote sensing techniques. The outlined approach enabled us to robustly resolve variations of a complex glacier at sub-centennial timescales, while constraining the sedimentological imprint of other geomorphic catchment processes. From a paleoclimate perspective, our reconstruction reveals a dynamic Late Holocene climate, modulated by long-term shifts in regional circulation patterns. We also find evidence for rapid medieval glacier retreat as well as a

  4. Response of Glacier Flash Flood to Climate Warming in the Tarim River Basin%塔里木河流域冰川洪水对气候变暖的响应

    Institute of Scientific and Technical Information of China (English)

    沈永平; 王国亚; 邵春

    2007-01-01

    In past 50 years, the air temperature fluctuation was raising trend in Tarim River Basin. The annual mean temperature has increased by 0.3℃ in the whole Tarim River Basin, and by 0.6℃ in the mountain areas. With global warming, the frequency of unstable and extreme climatic events increased, glaciers retreating accelerated and snow meltwater increased have resulted in the more frequency of snow-ice disasters such as glacier debrisflow and glacier flash flood etc. Since 1980s, in the process of intense climate warming, glaciers melting intensified, ice temperature rose and glaciers flows accelerated, and lead to more glacial lakes and extending water storage capacity and stronger glacial lake outburst floods occurrence. It is proposed that the monitoring and evaluating of the impact of climate change on water resources and floods should be enhanced.

  5. The distribution and abundance ofa nuisance native alga, Didymosphenia geminata,in streams of Glacier National Park: Climate drivers and management implications

    Science.gov (United States)

    Muhlfeld, Clint C.; Jones, Leslie A.; E. William Schweiger,; Isabel W. Ashton,; Loren L. Bahls,

    2011-01-01

    Didymosphenia geminata (didymo) is a freshwater alga native to North America, including Glacier National Park, Montana. It has long been considered a cold-water species, but has recently spread to lower latitudes and warmer waters, and increasingly forms large blooms that cover streambeds. We used a comprehensive monitoring data set from the National Park Service (NPS) and USGS models of stream temperatures to explore the drivers of didymo abundance in Glacier National Park. We estimate that approximately 64% of the stream length in the park contains didymo, with around 5% in a bloom state. Results suggest that didymo abundance likely increased over the study period (2007–2009), with blooms becoming more common. Our models suggest that didymo abundance is positively related to summer stream temperatures and negatively related to total nitrogen and the distance downstream from lakes. Regional climate model simulations indicate that stream temperatures in the park will likely continue to increase over the coming decades, which may increase the extent and severity of didymo blooms. As a result, didymo may be a useful indicator of thermal and hydrological modification associated with climate warming, especially in a relatively pristine system like Glacier where proximate human-related disturbances are absent or reduced. Glacier National Park plays an important role as a sentinel for climate change and associated education across the Rocky Mountain region.

  6. The distribution and abundance of a nuisance native alga, Didymosphen Didymosphenia geminata, in streams of Glacier National Park: Climate drivers and management implications

    Science.gov (United States)

    William, Schweiger E.; Ashton, I.W.; Muhlfeld, C.C.; Jones, L.A.; Bahls, L.L.

    2011-01-01

    Didymosphenia geminata (didymo) is a freshwater alga native to North America, including Glacier National Park, Montana. It has long been considered a cold-water species, but has recently spread to lower latitudes and warmer waters, and increasingly forms large blooms that cover streambeds. We used a comprehensive monitoring data set from the National Park Service (NPS) and USGS models of stream temperatures to explore the drivers of didymo abundance in Glacier National Park. We estimate that approximately 64% of the stream length in the park contains didymo, with around 5% in a bloom state. Results suggest that didymo abundance likely increased over the study period (2007-2009), with blooms becoming more common. Our models suggest that didymo abundance is positively related to summer stream temperatures and negatively related to total nitrogen and the distance downstream from lakes. Regional climate model simulations indicate that stream temperatures in the park will likely continue to increase over the coming decades, which may increase the extent and severity of didymo blooms. As a result, didymo may be a useful indicator of thermal and hydrological modification associated with climate warming, especially in a relatively pristine system like Glacier where proximate human-related disturbances are absent or reduced. Glacier National Park plays an important role as a sentinel for climate change and associated education across the Rocky Mountain region.

  7. Constraints on southern hemisphere tropical climate change during the Little Ice Age and Younger Dryas based on glacier modeling of the Quelccaya Ice Cap, Peru

    Science.gov (United States)

    Malone, Andrew G. O.; Pierrehumbert, Raymond T.; Lowell, Thomas V.; Kelly, Meredith A.; Stroup, Justin S.

    2015-10-01

    Improving the late Quaternary paleoclimate record through climate interpretations of low-latitude glacier length changes advances our understanding of past climate change events and the mechanisms for past, present, and future climate change. Paleotemperature reconstructions at low-latitude glaciers are uniquely fruitful because they can provide both site-specific information and enhanced understanding of regional-scale variations due to the structure of the tropical atmosphere. We produce Little Ice Age (LIA) and Younger Dryas (YD) paleoclimate reconstructions for the Huancané outlet glacier of the Quelccaya Ice Cap (QIC) and low-latitude southern hemisphere regional sea surface temperatures (SSTs) using a coupled ice-flow and energy balance model. We also model the effects of long-term changes in the summit temperature and precipitiation rate and the effects of interannual climate variability on the Huancané glacier length. We find temperature to be the dominant climate driver of glacier length change. Also, we find that interannual climate variability cannot adequately explain glacier advances inferred from the geomorphic record, necessitating that these features were formed during past colder climates. To constrain our LIA reconstruction, we incorporate the QIC ice core record, finding a LIA air temperature cooling at the ice cap of between ˜0.7 °C and ˜1.1 °C and ˜0.4 °C and regional SSTs cooling of ˜0.6 °C. For the YD paleoclimate reconstructions, we propose two limits on the precipitation rate, since the ice core record does not extend into the Pleistocene: 1) the precipitation rate scales with the Clausius-Clapeyron relationship (upper limit on cooling) and 2) the precipitation rate increases by 40% (lower limit on cooling), which is an increase about twice as great as the regional increases realized in GCM simulations for the period. The first limit requires ˜1.6 °C cooling in ice cap air temperatures and ˜0.9 °C cooling in SSTs, and the

  8. Mass gain of glaciers in Lahaul and Spiti region (North India during the nineties revealed by in-situ and satellite geodetic measurements

    Directory of Open Access Journals (Sweden)

    C. Vincent

    2012-09-01

    Full Text Available The volume change of Chhota Shigri Glacier (India, 32° N between 1988 and 2010 has been determined using in-situ geodetic measurements. This glacier has experienced only a slight mass loss over the last 22 yr (–3.8 ± 1.8 m w.e.. Using satellite digital elevation models (DEM differencing and field measurements, we measure a negative mass balance (MB between 1999 and 2011 (–4.7 ± 1.8 m w.e.. Thus, we deduce a positive MB between 1988 and 1999 (+1.0 ± 2.5 m w.e.. Furthermore, satellite DEM differencing reveals a good correspondence between the MB of Chhota Shigri Glacier and the MB of an over 2000 km2 glaciarized area in the Lahaul and Spiti region during 1999–2011. We conclude that there has been no large ice wastage in this region over the last 22 yr, ice mass loss being limited to the last decade. This contrasts to the most recent compilation of MB data in the Himalayan range that indicates ice wastage since 1975, accelerating after 1990. For the rest of western Himalaya, available observations of glacier MBs are too sparse and discontinuous to provide a clear and relevant regional pattern of glacier volume change over the last two decades.

  9. Response of Glacier and Lake Dynamics in Four Inland Basins to Climate Change at the Transition Zone between the Karakorum And Himalayas.

    Directory of Open Access Journals (Sweden)

    Zhiguo Li

    Full Text Available Inland glacier and lake dynamics on the Tibetan Plateau (TP and its surroundings over recent decades are good indicators of climate change and have a significant impact on the local water supply and ecosystem. The glacier and lake changes in Karakoram are quite different from those of the Himalayas. The mechanisms of the complex and regionally heterogeneous behavior of the glacier and lake changes between the Karakorum and Himalayas are poorly understood. Based on satellite images and meteorological data of Shiquanhe, Hetian, and Yutian stations, we demonstrate that the overall retreat of glaciers and increase of lake area at the transition zone between the Karakoram and Himalayas (TKH have occurred since 1968 in response to a significant global climate change. Glacial areas in the Songmuxi Co basin, Zepu Co basin, Mang Co basin and Unnamed Co decreased by -1.98 ± 0.02 km2, -5.39 ± 0.02 km2, -0.01 ± 0.02 km2, and -0.12 ± 0.02 km2 during the study period, corresponding to losses of -1.42%, -2.86%, -1.54%, and -1.57%, respectively. The lake area of the Songmuxi Co, Zepu Co, Mang Co and Unnamed Co increased by 7.57 ± 0.02 km2, 8.53 ± 0.02 km2, 1.35 ± 0.02 km2, and 0.53 ± 0.02 km2, corresponding to growths of 30.22%, 7.55%, 11.39%, and 8.05%, respectively. Increases in temperature was the main reason for glacier retreat, whereas decreases in potential evapotranspiration of lakes, increases in precipitation, and increases in melt water from glaciers and frozen soil all contributed to lake area expansion.

  10. A 14.000-year History of the Helheim Glacier - a record of Long-term Ice Dynamics in Relation to Climate

    Science.gov (United States)

    Bjørk, Anders; Kjær, Kurt; Larsen, Nicolaj; Olsen, Jesper; Khan, Shfaqat; Goldsack, Anne; Andersen, Thorbjørn; Schreiber, Norman; Andresen, Camilla; Korsgaard, Niels; Kjeldsen, Kristian; Stearns, Leigh

    2013-04-01

    Situated on the southeast coast of Greenland, the Helheim glacier is a major contributor of ice discharge and a milestone glacier in regards to understanding ice sheet dynamics to climate forcing. Within the last decade, the glacier has responded rapidly with retreat and increased calving to rising temperatures and inflow of warm oceanic water. Evidence from marine cores show that this has also occurred in warming periods during the last century. In this study we present lake core data revealing a 14.000 yr record of the dynamic behavior of the Helheim glacier. By targeting threshold lakes at the ice sheet margin upstream of the glacier, we receive a signal of glacial advance and retreat. The threshold lakes only receive glacial sediment when the ice margin is at an advanced position, similar to that of the present. As our cores penetrate into the deglaciation we have dated the onset of lake formation to ca 13.5 kyr bp - this suggests a much earlier deglaciation than what has previously been presented. Furthermore, our results reveal that the lakes have received glacial sediment several times throughout the Holocene.

  11. Mass balance, meteorology, area altitude distribution, glacier-surface altitude, ice motion, terminus position, and runoff at Gulkana Glacier, Alaska, 1996 balance year

    Science.gov (United States)

    March, Rod S.

    2003-01-01

    The 1996 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier Basin were evaluated on the basis of meteorological, hydrological, and glaciological data. Averaged over the glacier, the measured winter snow balance was 0.87 meter on April 18, 1996, 1.1 standard deviation below the long-term average; the maximum winter snow balance, 1.06 meters, was reached on May 28, 1996; and the net balance (from August 30, 1995, to August 24, 1996) was -0.53 meter, 0.53 standard deviation below the long-term average. The annual balance (October 1, 1995, to September 30, 1996) was -0.37 meter. Area-averaged balances were reported using both the 1967 and 1993 area altitude distributions (the numbers previously given in this abstract use the 1993 area altitude distribution). Net balance was about 25 percent less negative using the 1993 area altitude distribution than the 1967 distribution. Annual average air temperature was 0.9 degree Celsius warmer than that recorded with the analog sensor used since 1966. Total precipitation catch for the year was 0.78 meter, 0.8 standard deviations below normal. The annual average wind speed was 3.5 meters per second in the first year of measuring wind speed. Annual runoff averaged 1.50 meters over the basin, 1.0 standard deviation below the long-term average. Glacier-surface altitude and ice-motion changes measured at three index sites document seasonal ice-speed and glacier-thickness changes. Both showed a continuation of a slowing and thinning trend present in the 1990s. The glacier terminus and lower ablation area were defined for 1996 with a handheld Global Positioning System survey of 126 locations spread out over about 4 kilometers on the lower glacier margin. From 1949 to 1996, the terminus retreated about 1,650 meters for an average retreat rate of 35 meters per year.

  12. Himalayan glaciers: Combining remote sensing, field techniques and indigenous knowledge to understand spatio-temporal patterns of glacier changes and their impact on water resources

    Science.gov (United States)

    Racoviteanu, Adina

    With contradictory statements about "disappearing Himalayan glaciers" in the last few years, increasing concerns have been raised about the impact of snow and glacier changes on regional water supplies. Concomitantly, local communities in the western Himalaya report changes in glacier extents, snow cover and weather patterns. In response to perceived water scarcity, indigenous Himalayan cultures have begun a number of adaptive responses such as meltwater harvesting to construct "artificial" glaciers. This research addresses the need for a detailed assessment of glacier and climate parameters in the Himalaya, with the goal of identifying "at risk" glacierized areas and helping these local communities plan future water resources. The objectives of the research are threefold: 1) to review existing knowledge about glacier fluctuations and remote sensing methods for glacier mapping in the Himalaya; 3) to quantify spatio-temporal patterns of glacier changes in the eastern Himalaya in the last decades using remote sensing techniques and field measurements and 3) to quantify the role of glacier melt to streamflow using a combination of remote sensing and isotopic techniques. This thesis focuses on the monsoon-influenced eastern Himalaya (the Langtang and Khumbu regions in the Nepal Himalaya, and Sikkim in the Indian Himalaya). The research is grounded in extensive field surveys conducted from 2006 to 2010 across the Himalaya, including glacier mass balance expeditions, water sampling, ground-control point (GCP) acquisition and GPS-enabled photos. The goal of this research is to understand how topographic and climatic factors influence the rates of glacier change at various spatial scales, and how these changes re likely to affect future water resources. Multi-temporal (decadal) glacier datasets were derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor, Landsat ETM+, older topographic maps, declassified Corona imagery and very high

  13. Application and validation of long-range terrestrial laser scanning to monitor the mass balance of very small glaciers in the Swiss Alps

    Science.gov (United States)

    Fischer, Mauro; Huss, Matthias; Kummert, Mario; Hoelzle, Martin

    2016-06-01

    Due to the relative lack of empirical field data, the response of very small glaciers (here defined as being smaller than 0.5 km2) to current atmospheric warming is not fully understood yet. Investigating their mass balance, e.g. using the direct glaciological method, is a prerequisite to fill this knowledge gap. Terrestrial laser scanning (TLS) techniques operating in the near infrared range can be applied for the creation of repeated high-resolution digital elevation models and consecutive derivation of annual geodetic mass balances of very small glaciers. This method is promising, as laborious and potentially dangerous field measurements as well as the inter- and extrapolation of point measurements can be circumvented. However, it still needs to be validated. Here, we present TLS-derived annual surface elevation and geodetic mass changes for five very small glaciers in Switzerland (Glacier de Prapio, Glacier du Sex Rouge, St. Annafirn, Schwarzbachfirn, and Pizolgletscher) and two consecutive years (2013/14-2014/15). The scans were acquired with a long-range Riegl -6000 especially designed for surveying snow- and ice-covered terrain. Zonally variable conversion factors for firn and bare ice surfaces were applied to convert geodetic volume to mass changes. We compare the geodetic results to direct glaciological mass balance measurements coinciding with the TLS surveys and assess the uncertainties and errors included in both methods. Average glacier-wide mass balances were negative in both years, showing stronger mass losses in 2014/15 (-1.65 m w.e.) compared to 2013/14 (-0.59 m w.e.). Geodetic mass balances were slightly less negative but in close agreement with the direct glaciological ones (R2 = 0.91). Due to the dense in situ measurements, the uncertainties in the direct glaciological mass balances were small compared to the majority of measured glaciers worldwide (±0.09 m w.e. yr-1 on average), and similar to uncertainties in the TLS-derived geodetic mass

  14. Spatial-Temporal Characteristics of a Temperate-Glacier's Active-Layer Temperature and Its Responses to Climate Change:A Case Study of Baishui Glacier No. 1, Southeastern Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    Shijin Wang; Jiankuo Du; Yuanqing He

    2014-01-01

    Based on the historical documents and measured data from the active-layer temperature (ALT) at A, B and C locations (4 670, 4 720 and 4 770 m a.s.l.) on Baishui Glacier No. 1, southeastern Tibetan Plateau, this paper analyzed spatial-temporal characteristics of ALT and its relationship with air temperature, and revealed the response of the active layer ice temperature towards climate change in the monitoring period. The results showed that the influence of air temperature on the active-layer ice temperature had a hysteresis characteristic on the upper of ablation zone and the lag period in-creased gradually with the altitude elevating. The decrease amplitude of ALT in the accumulation pe-riod was far below its increase magnitude in the ablation period. At the same time, the mean glacier ice temperatures at 10 m depth (T10) in A, B and C profile were obviously higher than most of glaciers pre-viously studied. Measured data also showed that the mean ALT increased by 0.24 °C in 0.5-8.5 m depth of the C profile during 28 years from July 11, 1982 to July 10, 2009.

  15. Glacier shrinkage and water resources in the Andes

    Science.gov (United States)

    Francou, Bernard; Coudrain, Anne

    For more than a century glaciers around the world have been melting as air temperatures rise due to a combination of natural processes and human activity. The disappearance of these glaciers can have wide-ranging effects, such as the creation of new natural hazards or changes in stream flow that could threaten water suppliesSome of the most dramatic melting has occurred in the Andes mountain range in South America. To highlight the climatic and glacial change in the Andes and to encourage the scientific community to strengthen the glacier observation network that stretches from Colombia to the Patagonian ice fields, the Instituto Nacional de Recursos Naturales (INRENA), Perú, and the Institute of Research and Development (IRD), France, recently organized the second Symposium on Mass Balance of Andean Glaciers in Huaráz,Perú.

  16. Glacier change from the early Little Ice Age to 2005 in the Torngat Mountains, northern Labrador, Canada

    Science.gov (United States)

    Way, Robert G.; Bell, Trevor; Barrand, Nicholas E.

    2015-10-01

    The glaciers of the Torngat Mountains of northern Labrador are the southernmost of the Canadian Arctic and the easternmost of continental North America. Currently, 195 small mountain glaciers cover an area in excess of ~ 24 km2, confined mostly to small cirques and upland depressions. Using a combination of field and remote sensing methods this study reconstructs and dates the areal extent of Torngat glaciers at their Neoglacial maximums, enabling the first assessment of regional glacier change over the past several centuries. Mapped glacier paleomargins (n = 165) are compared to current (2005) glaciers and ice masses, showing a 52.5% reduction in glacier area, with at least 11 former glaciers altogether disappearing. Glacier change is spatially homogenous and independent of most geographic and topographic factors; however, glacier elevation and glacier size mitigated total change. Previously established lichen growth stations were revisited, and growth rates recalculated based on ~ 30-year-long records, enabling the construction of locally derived low- and high-altitude lichen growth curves. Using growth rates and in situ lichen measurements, the retreat from maximum Neoglacial moraine extents are suggested to have occurred between A.D. 1581 and 1673. These findings indicate a similar magnitude of post-LIA retreat to mountain glaciers elsewhere, yet a much earlier timing (~ 200 years) of retreat than other glaciers in the eastern Canadian Arctic. Though no definitive answer explaining this discrepancy is presented, evidence suggests that regional climate dynamics and the importance of solar radiation for Torngat glaciers may play an important role in local glacierization.

  17. Perturbation of dynamic response at short outlets glaciers of Jostedalsbreen, maritime South Norway?

    Science.gov (United States)

    Winkler, Stefan

    2010-05-01

    Mountain glaciers are key indicators of global climate change. Changes in glacier volume, area, and length are determined by the climate and related mass flux/glacier flow. For several aspects of sustainable development in high-mountain regions (hydro-electric energy, water supply, tourism, etc.) it is crucial to estimate future glacier variations. Therefore, the interactions and relationships between individual meteorological and glaciological parameters need to be known before any model can be applied. Due to their steep mass balance gradient and high mass turnover, maritime mountain glaciers might respond very sensitively to changes of predominant weather or climate conditions. The steep outlet glaciers of Jostedalsbreen, western South Norway, underwent two fairly contrasting periods during the past 20 years. Interpretation of this ‘extreme' behaviour presented here deserved special attention. Detailed analysis of mass-balance, length variation, and climate data from maritime Southern Norway reveals their variations are not entirely determined by air temperature changes. A considerable increase in ice mass and related frontal advance during the AD 1990s was caused by increased winter precipitation. By contrast, a frontal retreat starting around AD 2000 continued and accelerated in recent years. Although above-average summer air temperatures unambiguously were responsible for this retreat, its proportion significantly exceeded the slight contemporary glacier mass loss. Since 2000, length variations at the short outlets of Jostedalsbreen seem to be decoupled from the net mass-balance data series. Additionally, the dynamic response of the glacier front to net balance and mass flux variations has been disturbed. Previously applicable terminus reaction times of 3 to 4 years have been replaced by an immediate response to higher summer air temperatures. The correlation of net balance to length variation dropped significant since AD 2000. Comparable changes between

  18. A data set of worldwide glacier length fluctuations

    OpenAIRE

    P. W. Leclercq; Oerlemans, J.; H. J. Basagic; I. Bushueva; Cook, A. J.; Le Bris, R.

    2014-01-01

    Glacier fluctuations contribute to variations in sea level and historical glacier length fluctuations are natural indicators of past climate change. To study these subjects, long-term information of glacier change is needed. In this paper we present a data set of global long-term glacier length fluctuations. The data set is a compilation of available information on changes in glacier length worldwide, including both measured and reconstructed glacier length fluctuations. All...

  19. Satellite Observations of Glacier Advances and Retreat in the Western Karakoram

    Science.gov (United States)

    Haritashya, U. K.; Bishop, M. P.; Shroder, J. F.; Bulley, H. N.

    2007-12-01

    Debris-covered alpine glaciers around the world have been retreating and downwasting. This suggests glacier response to atmospheric warming. Recent studies in the eastern Himalaya have shown systematic retreat for many glaciers. In the western Himalaya, however, systematic and quantitative data are not yet available to determine glacier sensitivity and mass balance trend. Given the paucity of bench-mark glaciers in the Himalaya, remote-sensing-based studies are required to obtain baseline information and produce estimates of advance and retreat rates. Consequently, our objectives were to assess glacier fluctuations in the western Karakoram of Pakistan as a part of the Global Land Ice Measurements from Space (GLIMS) project. Specifically, we used multi- temporal satellite data (ASTER 09/13/2004, Landsat TM 10/15/1992, and Landsat MSS 07/15/1992) to quantitatively assess terminus fluctuations. Results indicate that more than 50 percent of the sampled large and large-medium sized glaciers are advancing, and/or exhibit similar terminus positions to past positions. For example, Bualtar Glacier is advancing at the rate of 11 m/yr. On the other hand, most of the small-medium to small glaciers, such as Mani Glacier are retreating (15 m/yr). Some of these glaciers have also shown strong downwasting characteristics in the form of increased frequency and size of supraglacial lakes. Collectively, our results indicate that these glaciers may be responding differently to the current climatic conditions than in the eastern Himalaya (east of the Karakoram) and Wakhan Pamir region (northwest of the Karakoram). These quantitative results from remote-sensing studies also indicate that glacier fluctuations in this region are spatially and temporally complex. These complexities may be governed by multi-scaled topographic effects, as well as by variations in winter precipitation and decreases in summer temperature from increased cloudiness, as suggested by others.

  20. Response of the snowmelt and glacier runoff to the climate warming-up in the last 40 years in Xinjiang Autonomous Region, China

    Institute of Scientific and Technical Information of China (English)

    叶佰生; 丁永建; 康尔泗; 李纲; 韩添丁

    1999-01-01

    Some analytical results of the measured runoff during 1950s to 1980s at outlet hydrological stations of 33 main rivers and climatic data collected from 84 meteorological stations in Xinjiang Autonomous Region are presented.Comparison of hydrological and climatic parameters before and after 1980 shows that the spring runoff for most rivers after 1980s increased obviously at a rate of about 10%, though the spring air temperature did not rise very much. Especially,an increment by 20% for alpine runoff is observed during May when intensive snow melting occurred in the alpine region. To the contrary, the runoff in June decreased about 5%. When the summer or annual runoff is taken into account,direct relationship can be found between the change in runoff and the ratio of glacier-coverage, except the runoff in August when the glacier melting is strong, indicating that climatic warming has an obvious effect on the contribution of glacier melting to the runoff increase.

  1. Glacier length, area and volume changes in the Himalaya: an overview and specific examples

    Science.gov (United States)

    Bolch, T.; Bhambri, R.; Kamp, U.; Pieczonka, T.

    2011-12-01

    advancing glaciers. This is consistent with existing studies of the Karakoram glaciers. However, area and length changes show indirect signals only while the mass balance is most directly linked to climate. Debris cover on glaciers which is common throughout the Himalaya further influences glacier melt. Existing studies show that area and length changes are reduced in comparison to debris-free glaciers. Currently no long-term in-situ glacier mass balance measurements exist. Remote sensed derived geodetic mass balance estimations are a suitable tool to improve the knowledge on the reaction of glaciers to climate change. Detailed investigations on the debris-covered glaciers in Khumbu Himalaya based on stereo Corona, ASTER and Cartosat-1 data revealed a specific mass balance of -0.32 ± 0.08 m w.e. a-1 between 1972 and 2007 which is within the global mean. The surface lowering is significant for all glaciers despite thick debris-cover. Consistently, preliminary results of the large debris-covered Zemu Glacier in Sikkim/Eastern Indian Himalaya indicate significant mass loss but only a slight reduction in length. Further analyses are under way and also climatic considerations will be addressed.

  2. Relative importance of glacier contributions to water supply in a changing climate

    Science.gov (United States)

    The Snowmelt Runoff Model (SRM) was designed for simulation, forecasting, and future assessments, such as the effects of climate change. The most recent version of SRM uses the Microsoft Windows operating system and operates efficiently in the PC environment. A formalized algorithm for assessing ...

  3. Surface terrain characteristics and monsoon season mass balance of debris-covered glaciers in the Khumbu Himal, Nepal, obtained from high resolution Pléiades imagery.

    Science.gov (United States)

    Klug, Christoph; Nicholson, Lindsey; Rieg, Lorenzo; Sailer, Rudolf; Wirbel, Anna

    2016-04-01

    Debris-covered glaciers in the eastern Himalaya have pronounced surface relief consisting of hummocks and hollows, ice cliffs, lakes and former lake beds. This relief and spatially variable surface properties are expected to influence the spatially distributed surface energy balance and related ice mass loss and atmospheric interactions, but only a few studies have so far explicitly examined the nature of the surface terrain and its textures . In this work we present a new high-resolution digital terrain model (DTM) of a portion of the Khumbu Himal in the eastern Nepalese Himalaya, derived from Pléiades satellite imagery sampled in spring 2015. We use this DTM to study the terrain characteristics of five sample glaciers and analyse the inter- and intra- glacier variability of terrain characteristics in the context of glacier flow velocities and surface changes presented in previous studies in the area. In parallel to this analysis we also present the seasonal geodetic mass balance between spring and fall 2015, and relate it to the terrain properties, surface velocity and limited knowledge of the local lapse rates in meteorological conditions during this monsoon season.

  4. Glacier Changes in the Cordillera Blanca, Peru, Derived From SPOT5 Imagery, GIS and Field- Based Measurements

    Science.gov (United States)

    Racoviteanu, A.; Arnaud, Y.; Williams, M. W.; Singh Khalsa, S.

    2007-12-01

    There is urgency in deriving an extensive dataset for deriving glacier changes within the Cordillera Blanca, Peru, in a cost-effective and timely manner. Rapid glacial retreat during the last decades in this area poses a threat for water resources, hydroelectric power and local traditions. While there is some information on decadal changes in glacier extents, there still remains a paucity of mass balance measurements and glacier parameters such as hypsometry, size distribution and termini elevations. Here we investigate decadal changes in glacier parameters for Cordillera Blanca of Peru using data from Système Probatoire d'Observation de la Terre (SPOT) sensor, an old glacier inventory from 1970 aerial photography, field-based mass balance measurements and meteorological observations. Here we focus on: constructing a geospatial glacier inventory from 2003 SPOT scenes; mass balance estimations using remote sensing and field data; frequency distribution of glacier area; changes in termini elevations; hypsometry changes over time; glacier topography (slope, aspect, length/width ratio); AAR vs. mass balance for Artesonraju and Yanamarey benchmark glaciers; precipitation and temperature trends in the region. Over the last 25 years, mean temperatures increases of 0.09 deg.C/yr were greater at lower elevation than the 0.01 deg.C/yr at higher elevations, with little change in precipitation. Comparison of the new SPOT-based glacier inventory with the 1970 inventory shows that glaciers in Cordillera Blanca retreated at a rate of 0.6% per year over the last three decades, with no significant differences in the rate of area loss between E and W side. At lower elevations there is an upward shift of glacier termini along with a decrease in glacier area. Small glaciers are losing more area than large glaciers. Based on the relationship between specific mass balance (bn) and accumulation area ratio (AAR) for the two benchmark glaciers, we predicted a steady-state equilibrium line

  5. New inventory of glaciers in southeastern part of the Eastern Sayan Mountains

    Directory of Open Access Journals (Sweden)

    E. Yu. Osipov

    2013-01-01

    Full Text Available Satellite images with high (Quick Bird, 2006, WorldView-1, 2008, 0.5–0.6 m and middle (Landsat-7 ETM +, 2001, 15–30 m resolution were used to map contemporary glaciers on two mountain peaks of south-eastern part of East Sayan Ridge – Munky Sardyk (3491 m a.s.l. and Topographov (3089 m a.s.l.. Topographic maps of 1978 and 1981 and Landsat-7 images (summer 2001 were used to assess glacier changes during second half of XX century. Modern terminal and lateral moraines near glacier snouts were used to reconstruct former outlines during the end of the Little Ice Age (middle of XIX century. Also SRTM data and GPS-surveys in Munku-Sardyk area were applied to measure glacier altitudes. GIS technologies allowed forming digital glacier data base with attribute information and new inventory was made. Totally 13 glaciers with area of 5.1 km² were investigated and mapped. Glaciers are located in vertical range from 2800–3490 m a.s.l. (Munku-Sardyk area and 2340–2950 m a.s.l. (Topographov area. Firn line on glaciers vary from 2540 to 3110 m a.s.l., rising to the southeast. On average, over the past 160 years (since the end of the Little Ice Age glaciers have significantly decreased. Ice area has decreased by 49%, length has diminished by 570 m, the glacier snouts has risen by 124 m. Analysis of regional climate data shows that the rate of deglaciation is well correlated with summer temperatures increasing in the second half of XX century, especially in 1980–1990s. A tendency to recover glacier mass balance was revealed during the last decade based on climatic data.

  6. Glacier fluctuations, global temperature and sea-level change

    NARCIS (Netherlands)

    Leclercq, P.W.

    2012-01-01

    The current world-wide glacier retreat is a clear sign of global warming. In addition, glaciers contribute to sea-level rise as a consequence of the current retreat. In this thesis we use records of past glacier fluctuations to reconstruct past climate variations and the glacier contribution to sea-

  7. Numerical simulations of Gurenhekou Glacier on the Tibetan Plateau using a full-Stokes ice dynamical model

    Directory of Open Access Journals (Sweden)

    L. Zhao

    2013-01-01

    Full Text Available We investigate the impact of climate change on a small Tibetan glacier that is representative of the tens of thousands of mountain glaciers in the region. We apply a three-dimensional, thermo-mechanically coupled full-Stokes model to Gurenhekou Glacier located in the southern Tibetan Plateau. The steep and rugged geometry requires use of such a flow model to simulate the dynamical evolution of the glacier. We parameterize the temperature and mass balance using nearby automatic weather stations and an energy balance model for another glacier in the same mountain range. Summer air temperature increased at 0.02 K a−1 over the past 50 yr, and the glacier has retreated at an average rate of 8.3 m a−1. Prognostic simulations suggest an accelerated retreating rate up to 14 m a−1 for the next 50 yr under continued steady warming, which is consistent with observed increased retreat in the last decade. However, regional climate models suggest a marked increase in warming rate over Tibet during the 21st century, and this rate causes about a 1% per year loss of glaciated area and glacier volume. These changes imply that this small glacier will probably disappear in a century. Although Tibetan glaciers are not particularly sensitive to climate warming, the rather high warming rates predicted by regional climate models combined with the small sizes of most Tibetan glaciers suggest that significant numbers of glaciers will be lost in the region during the 21st century.

  8. The length of the glaciers in the world

    DEFF Research Database (Denmark)

    Machguth, Horst; Huss, M.

    2014-01-01

    are longer than 10km with Bering Glacier (Alaska/Canada) being the longest glacier in the world at a length of 196 km. Based on model output we derive global and regional area-length scaling laws. Differences among regional scaling parameters appear to be related to characteristics of topography and glacier...... mass balance. The present study adds glacier length as a central parameter to global glacier inventories. Global and regional scaling laws might proof beneficial in conceptual glacier models....

  9. Changes of the Hailuogou Glacier, Mt. Gongga,China, against the Background of Global Warming in the Last Several Decades

    Institute of Scientific and Technical Information of China (English)

    He Yuanqing; Li Zongxing; Yang Xiaomei; Jia Wenxiong; He Xianzhong; Song Bo; Zhang Ningning; Liu Qiao

    2008-01-01

    Great change, associated with global warming, has occurred at the Hailuogou (海螺沟)has retreated 1 822 m in the past 106 years, with an annual mean retreat of 17.2 m, and the front elevation has risen by 300 m since 1823. Comparison of glacier variations and temperature fluctuations in China and the Northern Hemisphere, over the last 100 years, indicates that glacier retreat stages occurred during the warm phase, and vice versa. Mass balance records during 1959/60--2003/04 have shown that the glacier has suffered a constant mass loss of snow and ice. The accumulated mass balance, -10.83 m water equivalent, indicates an annual mean value of -0.24 m water equivalent. The correlation between the mass balance and temperature is significant, which also indicates that climate warming is the crucial cause of glacier loss.Local hydrological and climatic data demonstrate that runoff from the glacier has been increasing both seasonally and annually.The correlation analysis and trend analysis indicate that ice and snow melted water is the main cause of an increase in the runoff. As the climate has become warmer, changes in the glacier surface morphology have obviously occurred. These include a decrease in glacier thickness, enlargement of glacial caves, and reduction of the size of clefts on the glacier surface. The ablation period has lengthened and the ablation area has expanded. A variety of factors thus provide evidence that the Hailuogou glacier has suffered a rapid loss of snow and ice as a result of climatic warming.

  10. Glaciers, ice sheets, and sea level: effect of a CO/sub 2/-induced climatic change

    Energy Technology Data Exchange (ETDEWEB)

    None

    1985-09-01

    The workshop examined the basic questions of how much water has been exchanged between land ice and ocean during the last century, what is happening now, and, given existing climate-modeling prediction, how much exchange can be expected in the next century. In addition, the evidence for exchange was examined and gaps in that evidence were identified. The report includes the 23 presentations made at the workshop, summarizes the workshop discussion, and presents the Committee's findings and recommendations. Separate abstracts have been prepared for the 23 presentations.

  11. Incorporation of the Mass Concentration and the New Snow Albedo Schemes into the Global Forecasting Model, GEOS-5 and the Impact of the New Schemes over Himalayan Glaciers

    Science.gov (United States)

    Yasunari, Teppei

    2012-01-01

    Recently the issue on glacier retreats comes up and many factors should be relevant to the issue. The absorbing aerosols such as dust and black carbon (BC) are considered to be one of the factors. After they deposited onto the snow surface, it will reduce snow albedo (called snow darkening effect) and probably contribute to further melting of glacier. The Goddard Earth Observing System version 5 (GEOS-5) has developed at NASA/GSFC. However, the original snowpack model used in the land surface model in the GEOS-5 did not consider the snow darkening effect. Here we developed the new snow albedo scheme which can consider the snow darkening effect. In addition, another scheme on calculating mass concentrations on the absorbing aerosols in snowpack was also developed, in which the direct aerosol depositions from the chemical transport model in the GEOS-5 were used. The scheme has been validated with the observed data obtained at backyard of the Institute of Low Temperature Science, Hokkaido University, by Dr. Teruo Aoki (Meteorological Research Institute) et aL including me. The observed data was obtained when I was Ph.D. candidate. The original GEOS-5during 2007-2009 over the Himalayas and Tibetan Plateau region showed more reductions of snow than that of the new GEOS-5 because the original one used lower albedo settings. On snow cover fraction, the new GEOS-5 simulated more realistic snow-covered area comparing to the MODIS snow cover fraction. The reductions on snow albedo, snow cover fraction, and snow water equivalent were seen with statistically significance if we consider the snow darkening effect comparing to the results without the snow darkening effect. In the real world, debris cover, inside refreezing process, surface flow of glacier, etc. affect glacier mass balance and the simulated results immediately do not affect whole glacier retreating. However, our results indicate that some surface melting over non debris covered parts of the glacier would be

  12. Response of regional climate and glacier ice proxies to El Niño-Southern Oscillation (ENSO in the subtropical Andes

    Directory of Open Access Journals (Sweden)

    E. Dietze

    2008-02-01

    Full Text Available El Niño-Southern Oscillation (ENSO is an important element of earth's ocean-climate system. To further understand its past variability, proxy records from climate archives need to be studied. Ice cores from high alpine glaciers may contain high resolution ENSO proxy information, given the glacier site is climatologically sensitive to ENSO. We investigated signals of ENSO in the climate of the subtropical Andes in the proximity of Cerro Tapado glacier (30°08' S, 69°55' W, 5550 m a.s.l., where a 36 m long ice core was drilled in 1999 (Ginot, 2001. We used annual and semi-annual precipitation and temperature time series from regional meteorological stations and interpolated grids for correlation analyses with ENSO indices and ice core-derived proxies (net accumulation, stable isotope ratio δ18O, major ion concentrations. The total time period investigated here comprises 1900 to 2000, but varies with data sets. Only in the western, i.e. Mediterranean Andes precipitation is higher (lower during El Niño (La Niña events, especially at higher altitudes, due to the latitudinal shift of frontal activity during austral winters. However, the temperature response to ENSO is more stable in space and time, being higher (lower during El Niño (La Niña events in most of the subtropical Andes all year long. From a northwest to southeast teleconnection gradient, we suggest a regional water vapour feedback triggers temperature anomalies as a function of ENSO-related changes in regional pressure systems, Pacific sea surface temperature and tropical moisture input. Tapado glacier ice proxies are found to be predominantly connected to eastern Andean summer rain climate, which contradicts previous studies and the modern mean spatial boundary between subtropical summer and winter rain climate derived from the grid data. The only ice core proxy showing a response to ENSO is the major ion concentrations, via local temperature indicating

  13. Changes of Monsoonal Temperate Glaciers in China during the Past Several Decades under the Background of Global Warming

    Institute of Scientific and Technical Information of China (English)

    Wilfred; H.Theakstone

    2008-01-01

    Based on various data,it can be concluded that eight monsoonal temperate glaciers in China were in stationary or ad-vancing between 1900s~1930s and 1960s~1980s,and were in retreating during 1930s~1960s and 1980s~present under the background of climate warming.The total glacier area has reduced by 3.11 km2 with a mean front altitude rise of 3.2 m/yr and 4 glaciers have disappeared in Mt.Yulong during 1957~1999.Mass balance records indicated that glaciers had suf-fered a constant mass loss of snow and ice during the last several decades,and the accumulated mass balance in Hailuogou basin in Mt.Gongga was 10.83 m water equivalent in the past 45 years with a annual mean value of-0.24 m,and the value at Baishui glacier No.1 was-11.38 m water equivalent in the past 52 years with-0.22 m/yr.The inverse variation between mass balance and temperature in China and the Northern Hemisphere reflected that climate warming is mainly corresponding to constant ice and snow mass loss in the past 50 years.The change of the glaciers’ surface mor-phology has occurred since the 1980s,such as enlargement of glacier-lake and ice falls,resulted from the accelrative cli-mate warming.

  14. The influence of snow cover thickness on the thermal regime of Tete Rousse Glacier (Mont Blanc range, 3200 m a.s.l.) : consequences for outburst flood hazards and glacier response to climate change

    OpenAIRE

    Gilbert, A.; Vincent, C.; Wagnon, Patrick; E. Thibert; A. Rabatel

    2012-01-01

    Tete Rousse Glacier (French Alps) was responsible for an outburst flood in 1892 that devastated the village of St Gervais-Le Fayet close to Chamonix, causing 175 fatalities. Changes in the hydrothermal configuration of the glacier are suspected to be the cause of this catastrophic outburst flood. In 2010, geophysical surveys of this glacier revealed a subglacial lake that was subsequently drained artificially. The processes controlling the thermal regime of the glacier have been investigated ...

  15. Post-LIA glacier changes along a latitudinal transect in the Central Italian Alps

    Science.gov (United States)

    Scotti, R.; Brardinoni, F.; Crosta, G. B.

    2014-12-01

    The variability of glacier response to atmospheric temperature rise in different topo-climatic settings is still a matter of debate. To address this question in the Central Italian Alps, we compile a post-LIA (Little Ice Age) multitemporal glacier inventory (1860-1954-1990-2003-2007) along a latitudinal transect that originates north of the continental divide in the Livigno Mountains and extends south through the Disgrazia and Orobie ranges, encompassing continental-to-maritime climatic settings. In these sub-regions, we examine the area change of 111 glaciers. Overall, the total glacierized area has declined from 34.1 to 10.1 km2, with a substantial increase in the number of small glaciers due to fragmentation. The average annual decrease (AAD) in glacier area has risen by about 1 order of magnitude from 1860-1990 (Livigno: 0.45; Orobie: 0.42; and Disgrazia: 0.39 % a-1) to 1990-2007 (Livigno: 3.08; Orobie: 2.44; and Disgrazia: 2.27 % a-1). This ranking changes when considering glaciers smaller than 0.5 km2 only (i.e., we remove the confounding caused by large glaciers in Disgrazia), so that post-1990 AAD follows the latitudinal gradient and Orobie glaciers stand out (Livigno: 4.07; Disgrazia: 3.57; and Orobie: 2.47 % a-1). More recent (2007-2013) field-based mass balances in three selected small glaciers confirm post-1990 trends showing the consistently highest retreat in continental Livigno and minimal area loss in maritime Orobie, with Disgrazia displaying transitional behavior. We argue that the recent resilience of glaciers in Orobie is a consequence of their decoupling from synoptic atmospheric temperature trends, a decoupling that arises from the combination of local topographic configuration (i.e., deep, north-facing cirques) and high winter precipitation, which ensures high snow-avalanche supply, as well as high summer shading and sheltering. Our hypothesis is further supported by the lack of correlations between glacier change and glacier attributes in

  16. Post-LIA glacier changes along a latitudinal transect in the Central Italian Alps

    Directory of Open Access Journals (Sweden)

    R. Scotti

    2014-07-01

    Full Text Available The variability of glacier response to atmospheric temperature rise in different topo-climatic settings is still matter of debate. To address this question in the Central Italian Alps we compile a post-LIA (Little Ice Age multitemporal glacier inventory (1860-1954-1990-2003-2007 along a latitudinal transect that originates north of the continental divide in the Livigno mountains, and extends south through the Disgrazia and Orobie ranges, encompassing continental-to-maritime climatic settings. In these sub-regions we examine area change of 111 glaciers. Overall, total glacierized area has declined from 34.1 to 10.1 km2, with a substantial increase in the number of small glaciers due to fragmentation. Average annual decrease (AAD in glacier area has risen of about an order of magnitude from 1860–1990 (Livigno: 0.45; Orobie: 0.42; and Disgrazia: 0.39 % a−1 to 1990–2007 (Livigno: 3.08; Orobie: 2.44; and Disgrazia: 2.27 % a−1. This ranking changes when considering glaciers 2 only (i.e., we remove the confounding caused by large glaciers in Disgrazia, so that post-1990 AAD follows the latitudinal gradient and Orobie glaciers stand out (Livigno: 4.07; Disgrazia: 3.57; and Orobie: 2.47 % a−1. More recent (2007–2013 field-based mass balances in three selected small glaciers confirm post-1990 trends showing consistent highest retreat in continental Livigno and minimal area loss in maritime Orobie, with Disgrazia displaying a transitional behaviour. We argue that the recent resilience of glaciers in Orobie is a consequence of their decoupling from synoptic atmospheric temperature trends. A decoupling that arises from the combination of local topographic configuration (i.e., deep, north-facing cirques and high winter precipitation, which ensures high snow-avalanche supply, as well as high summer shading and sheltering. Our hypothesis is further supported by the lack of correlations between glacier change and glacier attributes in Orobie, as well

  17. Modelled glacier equilibrium line altitudes during the mid-Holocene in the southern mid-latitudes

    Directory of Open Access Journals (Sweden)

    C. Bravo

    2015-03-01

    Full Text Available Glacier behaviour during the mid-Holocene (MH, 6000 year BP in the Southern Hemisphere provides observational data to constrain our understanding of the origin and propagation of palaeo-climatic signals. We examine the climatic forcing of glacier expansion in the MH by evaluating modelled glacier equilibrium line altitude (ELA and climate conditions during the MH compared with pre-industrial time (PI, year 1750 in the mid latitudes of the Southern Hemisphere, specifically in Patagonia and the South Island of New Zealand. Climate conditions for the MH are obtained from PMIP2 models simulations, which in turn force a simple glacier mass balance model to simulate changes in equilibrium-line altitude during this period. Climate conditions during the MH show significantly (p ≤ 0.05 colder temperatures in summer, autumn and winter, and significantly (p ≤ 0.05 warmer temperatures in spring. These changes are a consequence of insolation differences between the two periods. Precipitation does not show significant changes, but exhibits a temporal pattern with less precipitation from August to September and more precipitation from October to April during the MH. In response to these climatic changes, glaciers in both analysed regions have an ELA that is 15–33 m lower than PI during the MH. The main causes of this difference are the colder temperature during the MH, reinforcing previous results that mid-latitude glaciers are more sensitive to temperature change compared to precipitation changes. Differences in temperature have a dual effect on mass balance. First, during summer and early autumn less energy is available for melting. Second in late autumn and winter, lower temperatures cause more precipitation to fall as snow rather than rain, resulting in more accumulation and higher surface albedo. For these reasons, we postulate that the modelled ELA changes, although small, may help to explain larger glacier extents observed in the mid Holocene in

  18. Revealing glacier flow and surge dynamics from animated satellite image sequences: examples from the Karakoram

    Science.gov (United States)

    Paul, F.

    2015-04-01

    Although animated images are very popular on the Internet, they have so far found only limited use for glaciological applications. With long time-series of satellite images becoming increasingly available and glaciers being well recognized for their rapid changes and variable flow dynamics, animated sequences of multiple satellite images reveal glacier dynamics in a time-lapse mode, making the otherwise slow changes of glacier movement visible and understandable for a wide public. For this study animated image sequences were created from freely available image quick-looks of orthorectified Landsat scenes for four regions in the central Karakoram mountain range. The animations play automatically in a web-browser and might help to demonstrate glacier flow dynamics for educational purposes. The animations revealed highly complex patterns of glacier flow and surge dynamics over a 15-year time period (1998-2013). In contrast to other regions, surging glaciers in the Karakoram are often small (around 10 km2), steep, debris free, and advance for several years at comparably low annual rates (a few hundred m a-1). The advance periods of individual glaciers are generally out of phase, indicating a limited climatic control on their dynamics. On the other hand, nearly all other glaciers in the region are either stable or slightly advancing, indicating balanced or even positive mass budgets over the past few years to decades.

  19. Decadal region-wide and glacier-wide mass balances derived from multi-temporal ASTER satellite digital elevation models. Validation over the Mont-Blanc area

    Science.gov (United States)

    Berthier, Etienne; Cabot, Vincent; Vincent, Christian; Six, Delphine

    2016-06-01

    Since 2000, a vast archive of stereo-images has been built by the Advanced Spaceborne Thermal Emission and Reflection (ASTER) satellite. Several studies already extracted glacier mass balances from multi-temporal ASTER digital elevation models (DEMs) but they lacked accurate independent data for validation. Here, we apply a linear regression to a time series of 3D-coregistered ASTER DEMs to estimate the rate of surface elevation changes (dh/dtASTER) and geodetic mass balances of Mont-Blanc glaciers (155 km²) between 2000 and 2014. Validation using field and spaceborne geodetic measurements reveals large errors at the individual pixel level (> 1 m a-1) and an accuracy of 0.2-0.3 m a-1 for dh/dtASTER averaged over areas larger than 1 km². For all Mont-Blanc glaciers, the ASTER region-wide mass balance (-1.05±0.37 m water equivalent (w.e.) a-1) agrees remarkably with the one measured using Spot5 and Pléiades DEMs (-1.06±0.23 m w.e. a-1) over their common 2003-2012 period. This multi-temporal ASTER DEM strategy leads to smaller errors than the simple differencing of two ASTER DEMs. By extrapolating dh/dtASTER to mid-February 2000, we infer a mean penetration depth of about 9±3 m for the C-band Shuttle Radar Topographic Mission (SRTM) radar signal, with a strong altitudinal dependency (range 0-12 m). This methodology thus reveals the regional pattern of glacier surface elevation changes and improves our knowledge of the penetration of the radar signal into snow and ice.

  20. The Photographic History of Greenland's Glaciers - and how the historical data plays an important role in today's glacier research

    Science.gov (United States)

    Bjork, A. A.; Kjeldsen, K. K.; Korsgaard, N. J.; Aagaard, S.; Andresen, C. S.; Bamber, J. L.; van den Broeke, M.; Colgan, W. T.; Funder, S.; Khan, S. A.; Larsen, N. K.; Machguth, H.; Nuth, C.; Schomacker, A.; Kjaer, K. H.

    2015-12-01

    As the Greenland Ice Sheet and Greenland's glaciers are continuing to loss mass at high rates, knowledge of their past response to climatic changes is ever important. By harvesting the archives for images, both terrestrial and airborne, we are able to expand the record of glacier observation by several decades, thus supplying crucial knowledge on glacier behavior to important climatic transitions such as the end of the Little Ice Age and the early 20th Century warming. Here we show how a large collection of historical aerial images portray the glacial response to the Little Ice Age deglaciation in Greenland and document frontal change throughout the 20th Century. A detailed story of the LIA-deglaciation is told by supplementing with terrestrial photos that capture the onset of retreat and high resolution aerial images that portray geomorphological evidence of the Little Ice Age maximum extent. This work is the result of several generations of Greenland researches and their efforts to portray and document the state of the glaciers, and highlights that while interpretations and conclusions may be challenged and changed through time, the raw observations remain extremely valuable. Finally, we also show how archival data besides photos may play an important role in future glacier research in Greenland.

  1. 50 years of mass balance observations at Vernagtferner, Eastern Alps

    Science.gov (United States)

    Braun, Ludwig; Mayer, Christoph

    2016-04-01

    The determination and monitoring of the seasonal and annual glacier mass balances of Vernagtferner, Austria, started in 1964 by the Commission of Glaciology, Bavarian Academy of Sciences. Detailed and continuous climate- and runoff measurements complement this mass balance series since 1974. Vernagtferner attracted the attention of scientists since the beginning of the 17th century due to its rapid advances and the resulting glacier lake outburst floods in the Ötztal valley. This is one reason for the first photogrammetric survey in 1889, which was followed by frequent topographic surveys, adding up to more than ten digital elevation models of the glacier until today. By including the known maximum glacier extent at the end of the Little Ice Age in 1845, the geodetic glacier volume balances cover a time span of almost 170 years. The 50 years of glacier mass balance and 40 years of water balance in the drainage basin are therefore embedded in a considerably longer period of glacier evolution, allowing an interpretation within an extended frame of climatology and ice dynamics. The direct mass balance observations cover not only the period of alpine-wide strong glacier mass loss since the beginning of the 1990s. The data also contain the last period of glacier advances between 1970 and 1990. The combination of the observed surface mass exchange and the determined periodic volumetric changes allows a detailed analysis of the dynamic reaction of the glacier over the period of half a century. The accompanying meteorological observations are the basis for relating these reactions to the climatic changes during this period. Vernagtferner is therefore one of the few glaciers in the world, where a very detailed glacier-climate reaction was observed for many decades and can be realistically reconstructed back to the end of the Little Ice Age.

  2. Determining the Current and Future Health of Low-Latitude Andean Glaciers Using an Equilibrium Line Altitude Model and Hypsometric Data from the Randolph Glacier Inventory

    Science.gov (United States)

    Malone, A.; MacAyeal, D. R.

    2015-12-01

    understanding of the glacial impacts of contemporary and future warming. Also, this work provides analysis of processes and feedbacks between different climate variables important to glacier mass balances in a warming world, improving predictions for the fate of low-latitude Andean glaciers.

  3. Contribution of snow and glacier melt to discharge for highly glacierised catchments in Norway

    Directory of Open Access Journals (Sweden)

    M. Engelhardt

    2013-09-01

    Full Text Available Glacierised catchments significantly alter the streamflow regime due to snow and glacier meltwater contribution to discharge. In this study, we modelled the mass balance and discharge rates for three highly glacierised catchments (>50% glacier cover in western Norway over the period 1961–2012. The spatial pattern of the catchments follows a gradient in climate continentality from west to east. The model uses gridded temperature and precipitation values from seNorge (http://senorge.no as input which are available at a daily resolution. It accounts for accumulation of snow, transformation of snow to firn and ice, evaporation and melt. The model was calibrated for each catchment based on measurements of seasonal glacier mass-balances and daily discharge rates. For validation, daily melt rates were compared with measurements from sonic rangers located in the ablation zones of two of the glaciers and an uncertainty analysis was performed for the third catchment. The discharge contributions from snowmelt, glacier melt and rain were analysed with respect to spatial variations and temporal evolution. The model simulations reveal an increase of the relative contribution from glacier melt for the three catchments from less than 10% in the early 1990s to 15–30% in the late 2000s. The decline in precipitation by 10–20% in the same period was therefore overcompensated resulting in an increase of the annual discharge by 5–20%. Annual discharge sums and annual glacier melt are strongest correlated with annual and winter precipitation at the most maritime glacier and, with increased climate continentality, variations in both glacier melt contribution and annual discharge are becoming stronger correlated with variations in summer temperatures.

  4. Ice cores from Arctic sub-polar glaciers : Chronology and post-depositional processes deduced from radioactivity measurements

    NARCIS (Netherlands)

    Pinglot, J.F.; Vaikmae, R.A.; Kamiyama, K.; Igarashi, M.; Fritsche, D.; Wilhalms, F.; Koerner, R.; Henderson, L.; Isaksson, E.; Winther, J.G.; van de Wal, R.S.W.; Fournier, M; Bouisset, P.; Meijer, H.A.J.

    2003-01-01

    The response of Arctic ice masses to climate change is studied using ice cores containing information on past climatic and environmental features. Interpretation of this information requires accurate chronological data. Absolute dating of ice cores from sub-polar Arctic glaciers is possible using we

  5. Mass balance, meteorological, ice motion, surface altitude, runoff, and ice thickness data at Gulkana Glacier, Alaska, 1995 balance year

    Science.gov (United States)

    March, Rod S.

    2000-01-01

    The 1995 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier basin were evaluated on the basis of meteorological, hydrological, and glaciological data obtained in the basin. Averaged over the glacier, the measured winter snow balance was 0.94 meter on April 19, 1995, 0.6 standard deviation below the long-term average; the maximum winter snow balance, 0.94 meter, was reached on April 25, 1995; the net balance (from September 18, 1994 to August 29, 1995) was -0.70 meter, 0.76 standard deviation below the long-term average. The annual balance (October 1, 1994, to September 30, 1995) was -0.86 meter. Ice-surface motion and altitude changes measured at three index sites document seasonal ice speed and glacier-thickness changes. Annual stream runoff was 2.05 meters averaged over the basin, approximately equal to the long-term average. The 1976 ice-thickness data are reported from a single site near the highest measurement site (180 meters thick) and from two glacier cross profiles near the mid-glacier (270 meters thick on centerline) and low glacier (150 meters thick on centerline) measurement sites. A new area-altitude distribution determined from 1993 photogrammetry is reported. Area-averaged balances are reported from both the 1967 and 1993 area-altitude distribution so the reader may directly see the effect of the update. Briefly, loss of ablation area between 1967 and 1993 results in a larger weighting being applied to data from the upper glacier site and hence, increases calculated area-averaged balances. The balance increase is of the order of 15 percent for net balance.

  6. Assessment of interannual variations in the surface mass balance of 18 Svalbard glaciers from the Moderate Resolution Imaging Spectroradiometer/Terra albedo product

    OpenAIRE

    W. Greuell; Kohler, J.; F. Obleitner; Glowacki, P.; Melvold, K.; Bernsen, E.; J. Oerlemans

    2007-01-01

    We estimate annual anomalies of the surface mass balance of glaciers on Svalbard for the period 2000–2005 (six years), by calculating the so-called ‘‘satellite-derived mass balance’’ (Bsat) from time series of satellite-derived surface albedos. The method needs no other input variables. Surface albedos are extracted from the Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra albedo product. We validate the MODIS albedos by comparing them with in situ measurements on Kongsvegen, and w...

  7. Mass balance, meteorological, ice motion, surface altitude, and runoff data at Gulkana Glacier, Alaska, 1992 balance year

    Science.gov (United States)

    March, R.S.; Trabant, D.C.

    1996-01-01

    The 1992 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier basin were evaluated on the basis of meteorological, hydrological, and glaciological data measured in the basin and are reported herein. Averaged over the glacier, the measured winter snow balance was 0.97 meters on March 26, 1992; the maximum winter snow balance was 1.05 meters on May 19, 1992; the net balance (from September 8, 1991 to August 17, 1992) was -0.29 meters; and the annual balance (October 1, 1991 to September 30, 1992) was -0.38 meters. Ice surface, motion, and altitude changes measured at three index sites document seasonal changes in ice speed and glacier thickness. Annual stream runoff was 1.24 meters averaged over the basin.

  8. Mass balance, meteorological, ice motion, surface altitude, and runoff data at Gulkana Glacier, Alaska, 1994 balance year

    Science.gov (United States)

    March, Rod S.

    1998-01-01

    The 1994 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier basin were evaluated on the basis of meteorological, hydrological, and glaciological data obtained in the basin. Averaged over the glacier, the measured winter snow balance was 1.34 meters on April 29, 1994, 0.9 standard deviation above the long-term average; the maximum winter snow balance, 1.43 meters, was reached on April 18, 1994; the net balance (from September 8, 1993 to September 17, 1994) was -0.72 meter, 0.7 standard deviation below the long-term average. The annual balance (October 1, 1992, to September 30, 1993) was -0.88 meter. Ice-surface motion and altitude changes measured at three index sites document seasonal ice speed and glacier-thickness changes. Annual stream runoff was 1.93 meters averaged over the basin, approximately equal to the long-term average.

  9. Snow and Glacier Hydrology

    Science.gov (United States)

    Brubaker, Kaye

    The study of snow and ice is rich in both fundamental science and practical applications. Snow and Glacier Hydrology offers something for everyone, from resource practitioners in regions where water supply depends on seasonal snow pack or glaciers, to research scientists seeking to understand the role of the solid phase in the water cycle and climate. The book is aimed at the advanced undergraduate or graduate-level student. A perusal of online documentation for snow hydrology classes suggests that there is currently no single text or reference book on this topic in general use. Instructors rely on chapters from general hydrology texts or operational manuals, collections of journal papers, or their own notes. This variety reflects the fact that snow and ice regions differ in climate, topography, language, water law, hazards, and resource use (hydropower, irrigation, recreation). Given this diversity, producing a universally applicable book is a challenge.

  10. Mapping the Snow Line Altitude for Large Glacier Samples from Multitemporal Landsat Imagery

    Science.gov (United States)

    Rastner, P.; Nicholson, L. I.; Notarnicola, C.; Prinz, R.; Sailer, R.

    2015-12-01

    The cryosphere of mountain regions is fastly changing in response to climate change. This is particularly evident in global-scale glacier retreat. Trends in snow cover, however, are more difficult to determine, as annual fluctuations can be very large. Snow is an important parameter in the energy and mass balance of glaciers and the snow line altitude (SLA) at the end of the melting period can be considered as a proxy for the equilibrium line altitude (ELA). By frequently observing the SLA from satellite, region-wide monitoring of glaciers and improved calibration and validation of transient glacier (mass balance) models is possible. In the near future, frequent mapping of the SLA will be strongly facilitated by satellite missions like Sentinel 2A/B, where the same region will be covered every 5 days with 10 m spatial resolution. For this study we have developed an automated tool to derive the SLA for large glacier samples from remote sensing data. The method is first applied in the Ötztal Alps (Austria) where reliable in-situ data of mass balance and ELA are available for several glaciers over a 30-years period. The algorithm currently works with multi-temporal Landsat imagery (1972-2015), digital glacier outlines and a high-quality national DEM. All input datasets are atmospherically and topographically pre-processed before the SLA is automatically retrieved for each glacier. The remote-sensing derived SLA is generally about 200 m lower than the ELA, however, a clear trend in the altitude of the end of summer snow line is detectable (~ 200 m), which is in agreement with the ELA trend observed in the field. After bias correction and conversion to mass balance, the variability in observed mass balance can be well reproduced from the satellite-derived SLA time series. This is promising for application of the approach in other regions.

  11. Climatic and environmental implications from organic matter in Dasuopu glacier in Xixiabangma in Qinghai-Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    谢树成; 姚檀栋; 康世昌; 段克勤; 徐柏青; L.; G.; Thompson

    1999-01-01

    A series of organic compounds in snow and ice were identified from Dasuopu glacier in Xixiabangma in Qinghai-Tibetan Plateau. Organic compounds derived from natural organisms include n-alkanes ranging from C15 to C33, normal monoearboxylie acids of C6—C18, n-alkan-2-ones of C24—C31 and esters. The unstable compounds widely present in lower troposphere disppear in the middle-upper troposphere. Lots of other organic compounds from petroleum residues were also unexpectedly identified from the glacier, covering pristane, phytane, extended tricyclie terpanes of C19—C29, C24 tetracyclic terpane, αβ hopane compounds of C27—C35, and cholestanes of C27—C29. The remote Xixiabangma region is unambiguously polluted from anthropology activities. The petroleum residues were proposed to be mainly from the Mideast and India, not from China. The organic pollutants from oil fires ignited during the well-known Gulf War which broke out in 1991 were also recorded in the glacier. S

  12. Runoff Modelling of the Khumbu Glacier, Nepal: Incorporating Debris Cover and Retreat Dynamics.

    Science.gov (United States)

    Douglas, James; Huss, Matthias; Jones, Julie; Swift, Darrel; Salerno, Franco

    2016-04-01

    Detailed studies on the future evolution and runoff of glaciers in high mountain Asia are scarce considering the region is so reliant on on this essential water source. This study adapts a model well-proven in the European Alps, the Glacier Evolution and Runoff Model (GERM), to simulate the behaviour of the Khumbu glacier, Nepal. GERM calculates glacier mass balance and runoff using a distributed temperature index model which has been modified such that the unique dynamics of debris covered glaciers, namely stagnation, thinning, and melt-inhibiting debris surfaces, are incorporated. Debris thickness is derived from both remote sensing and model based approaches allowing a suite of experiments to be conducted using various levels of debris cover. The model is driven by CORDEX-South Asia regional climate model (RCM) simulations, bias corrected using a quantile mapping technique based on in-situ data from the Pyramid meteorological station. Here, results are presented showing the retreat of the Khumbu glacier and the corresponding changes for annual and seasonal discharge until 2100, using varying melt parameters and debris thicknesses to assess the impact of debris cover on glacier evolution and runoff.

  13. Role of glaciers in watershed hydrology: ''Himalayan catchment'' perspective

    Directory of Open Access Journals (Sweden)

    R. J. Thayyen

    2009-07-01

    Full Text Available A large number of Himalayan glacier catchments are under the influence of humid climate with snowfall in winter (November–April and South-West monsoon in summer (June–September dominating the regional hydrology. Such catchments are defined as ''Himalayan catchment'', where the glacier melt water contributes to the river flow during the period of annual high flows produced by the monsoon. Other two major glacio-hydrological regimes of the Himalaya are winter snow dominated Alpine catchments of the Kashmir and Karakoram region and cold-arid regions of the Ladakh mountain range. Factors influencing the river flow variations in a ''Himalayan catchment'' were studied in a micro scale glacier catchment in the Garhwal Himalaya, covering an area of 77.8 km2. Discharge data generated from three hydrometric stations established at different altitudes of the Din Gad stream during the summer ablation period of 1998, 1999, 2000, 2001, 2003 and 2004. These data has been analysed along with winter/summer precipitation, temperature and mass balance data of the Dokriani glacier to study the role of the glacier and precipitation in determining the runoff variations along the stream continuum from the glacier snout to 2360 m a.s.l. Study shows that the inter-annual runoff variations in a ''Himalayan glacier catchment'' is directly linked with the precipitation rather than mass balance changes of the glacier. Study suggest that warming induced initial increase of glacier degraded runoff and subsequent decline is a glaciers mass balance response and cannot be translated as river flow response in a ''Himalayan catchment'' as suggested by the IPCC, 2007. Study also suggest that the glacier runoff critically influence the headwater river flows during the years of low summer discharge and proposes that the Himalayan catchment could experience higher river flows and positive

  14. An estimate of global glacier volume

    Directory of Open Access Journals (Sweden)

    A. Grinsted

    2013-01-01

    Full Text Available I assess the feasibility of using multivariate scaling relationships to estimate glacier volume from glacier inventory data. Scaling laws are calibrated against volume observations optimized for the specific purpose of estimating total global glacier ice volume. I find that adjustments for continentality and elevation range improve skill of area–volume scaling. These scaling relationships are applied to each record in the Randolph Glacier Inventory, which is the first globally complete inventory of glaciers and ice caps. I estimate that the total volume of all glaciers in the world is 0.35 ± 0.07 m sea level equivalent, including ice sheet peripheral glaciers. This is substantially less than a recent state-of-the-art estimate. Area–volume scaling bias issues for large ice masses, and incomplete inventory data are offered as explanations for the difference.

  15. Climate change impacts on mass movements--case studies from the European Alps.

    Science.gov (United States)

    Stoffel, M; Tiranti, D; Huggel, C

    2014-09-15

    This paper addresses the current knowledge on climate change impacts on mass movement activity in mountain environments by illustrating characteristic cases of debris flows, rock slope failures and landslides from the French, Italian, and Swiss Alps. It is expected that events are likely to occur less frequently during summer, whereas the anticipated increase of rainfall in spring and fall could likely alter debris-flow activity during the shoulder seasons (March, April, November, and December). The magnitude of debris flows could become larger due to larger amounts of sediment delivered to the channels and as a result of the predicted increase in heavy precipitation events. At the same time, however, debris-flow volumes in high-mountain areas will depend chiefly on the stability and/or movement rates of permafrost bodies, and destabilized rock glaciers could lead to debris flows without historic precedents in the future. The frequency of rock slope failures is likely to increase, as excessively warm air temperatures, glacier shrinkage, as well as permafrost warming and thawing will affect and reduce rock slope stability in the direction that adversely affects rock slope stability. Changes in landslide activity in the French and Western Italian Alps will likely depend on differences in elevation. Above 1500 m asl, the projected decrease in snow season duration in future winters and springs will likely affect the frequency, number and seasonality of landslide reactivations. In Piemonte, for instance, 21st century landslides have been demonstrated to occur more frequently in early spring and to be triggered by moderate rainfalls, but also to occur in smaller numbers. On the contrary, and in line with recent observations, events in autumn, characterized by a large spatial density of landslide occurrences might become more scarce in the Piemonte region. PMID:24630951

  16. Changes in the Mass Balance of the Greenland Ice Sheet in a Warming Climate During 2003-2009

    Science.gov (United States)

    Zwally, H. Jay; Luthcke, Scott

    2010-01-01

    Mass changes of the Greenland ice sheet (GIS) derived from ICESat and GRACE data both show that the net mass loss from GIS during 2003-2009 is about 175 Gt/year, which contributes 0.5mm/yr global sea-level rise. The rate of mass loss has increased significantly since the 1990's when the GIS was close to mass balance. Even though the GIS was close to mass balance during the 1990's, it was already showing characteristics of responding to8 warmer climate, specifically thinning at the margins and thickening inland at higher elevations. During 2003-2009, increased ice thinning due to increases in melting and acceleration of outlet glaciers began to strongly exceed the inland thickening from increases in accumulation. Over the entire GIS, the mass loss between the two periods, from increased melting and ice dynamics, increased by about 190 Gt/year while the mass gain, from increased precipitation and accumulation, increased by only about 15Gt/year. These ice changes occurred during a time when the temperature on GIS changed at rate of about 2K/decade. The distribution of elevation and mass changes derived from ICESat have high spatial resolution showing details over outlet glaciers, by drainage systems, and by elevation. However, information on the seasonal cycle of changes from ICESat data is limited, because the ICESat lasers were only operated during two to three campaigns per year of about 35 days duration each. In contrast, the temporal resolution of GRACE data, provided by the continuous data collection, is much better showing details of the seasonal cycle and the inter-annual variability. The differing sensitivity of the ICESat altimetry and the GRACE gravity methods to motion of the underlying bedrock from glacial isostatic adjustment (GIA) is used to evaluate the GIA corrections provided by models. The two data types are also combined to make estimates of the partitioning of the mass gains and losses among accumulation, melting, and ice discharge from outlet

  17. Recent changes detected on two glaciers at the northern part of James Ross Island, Antarctica

    Science.gov (United States)

    Nývlt, Daniel; Kopačková, Veronika; Láska, Kamil; Engel, Zbyněk.

    2010-05-01

    Antarctic Peninsula is one of the regions, which have been exposed to the most rapid warming of the Earth since 1950. Consequences of climate changes are clearly documented by recent disintegration of ice shelves on both sides of the Antarctic Peninsula as well as by the retreat of land-based glaciers. James Ross Island, located close to the northernmost tip of the Antarctic Peninsula, represents an excellent place to study changes in the glacier mass-balance and their sensitivity to a regional warming trend. Two different types of glaciers of the Ulu Peninsula, the Whisky Glacier and the Davies Dome have been studied. Multi-temporal remote sensing data (aerial photographs, Landsat MSS, TM and ETM+ and Aster satellite optical and thermal multispectral data) and field survey allowed detecting changes in extent (2-D) as well as calculating glacier mass-balance changes (3-D) for these two glaciers from 1977 to 2009. The Whisky Glacier is a well-delimited valley glacier located mostly below the local Equilibrium line altitude (ELA). The glacier with high-flow velocities is fed by an intensive snow accumulation caused by prevailing southwestern winds. The Whisky Glacier covers an area of 2.3 km2 and its altitude varies from 215 to 475 m a.s.l. The Davies Dome is a flat-bottom dome glacier. Significant parts of its surface are located above the ELA and limited flow velocities are characteristic for the most parts of its body. However, the Davies Dome has a single 500-700 m wide southwestern outlet flowing towards the Whisky Bay. The Davies Dome extends an area of 6.7 km2 and its altitude ranges from 0 to 514 m a.s.l. Both glaciers experienced massive extension of their ice tongues towards the Brandy Bay during the mid Holocene. Lateral moraines located in front of the both glaciers heading down to the left coast of the Brandy Bay document this event. According to the remote sensing data and field investigations both glaciers have retreated since 1977. Between 2006 and

  18. Glacier microseismicity

    Science.gov (United States)

    West, Michael E.; Larsen, Christopher F.; Truffer, Martin; O'Neel, Shad; LeBlanc, Laura

    2010-01-01

    We present a framework for interpreting small glacier seismic events based on data collected near the center of Bering Glacier, Alaska, in spring 2007. We find extremely high microseismicity rates (as many as tens of events per minute) occurring largely within a few kilometers of the receivers. A high-frequency class of seismicity is distinguished by dominant frequencies of 20–35 Hz and impulsive arrivals. A low-frequency class has dominant frequencies of 6–15 Hz, emergent onsets, and longer, more monotonic codas. A bimodal distribution of 160,000 seismic events over two months demonstrates that the classes represent two distinct populations. This is further supported by the presence of hybrid waveforms that contain elements of both event types. The high-low-hybrid paradigm is well established in volcano seismology and is demonstrated by a comparison to earthquakes from Augustine Volcano. We build on these parallels to suggest that fluid-induced resonance is likely responsible for the low-frequency glacier events and that the hybrid glacier events may be caused by the rush of water into newly opening pathways.

  19. Far-flung moraines: Exploring the feedback of glacial erosion on the evolution of glacier length

    Science.gov (United States)

    Anderson, Robert S.; Dühnforth, Miriam; Colgan, William; Anderson, Leif

    2012-12-01

    Over many glacial cycles, the glacial erosion of alpine valleys can be sufficient to reduce the length of glaciers in the most recent cycles. We document field cases illustrative of this erosional feedback and model the long-term evolution of glacier lengths analytically and numerically. The general feature we target is a moraine deposited well beyond the last glacial maximum (LGM) limit, which we refer to as a "far-flung" moraine. Firstly, we assemble published observations to illustrate that far-flung moraines are documented around the world. The observations suggest that the downvalley distance to such far-flung moraines can exceed the distance to LGM moraines by up to twofold. Secondly, we address the problem analytically, making several simplifying assumptions, to demonstrate that glacier length scales linearly with erosion depth. Finally, we employ a numerical model to test the analytical solution. This 1D (depth-integrated) flowline model includes: (i) a depth-averaged longitudinal coupling stress approximation, (ii) prescribed winter and summer surface mass balance profiles, (iii) evolving ice temperature calculated via the conventional heat equation, and (iv) glacier sliding velocity parameterized as a function of basal ice temperature and spatially and temporally variable prescribed flotation fraction. The simulated alpine landscape is modified through the competing processes of glacier erosion, which is dependent on glacier sliding velocity and prescribed bedrock erodibility, and prescribed uplift rate. The climate controlling surface mass balance is prescribed by time series of air temperature and snowfall approximated by the sum of two sinusoidal cycles. The recurrence statistics of these prescribed climate drivers closely match those of the marine isotopic record; hence the prescribed climate drivers faithfully mimic observed long-term climate drivers. Consistent with earlier landscape evolution studies, we find that the primary effect of repeated

  20. Using marine sediment archives to reconstruct past outlet glacier variability

    DEFF Research Database (Denmark)

    Andresen, Camilla Snowman; Straneo, Fiamma; Ribergaard, Mads;

    2013-01-01

    Ice-rafted debris in fjord sediment cores provides information about outlet glacier activity beyond the instrumental time period. It tells us that the Helheim Glacier, Greenland’s third most productive glacier, responds rapidly to short-term (3 to 10 years) climate changes....

  1. 贡嘎山海螺沟冰川物质平衡、水交换特征 及其对径流的影响%Mass Balance and Water Exchange of Hailuoguo Glacier in Mount Gongga and Their Influence on Glacial Melt Runoff

    Institute of Scientific and Technical Information of China (English)

    谢自楚; 苏珍; 冯清华; 沈永平

    2001-01-01

    the original level just before increasing (critical level). The sensitivity analysis on the response of glacier mass balance to meteorological Variations shows that, a 1 K increase of air temperature or a 10 % reduction of precipitation, the responsive values for bn are -214 mm and 354 mm respectively. On the condition that the climate continues getting warmer and more meist, the time at which the discharge reaches to the critical level will proloug to about 2050's. Then the area and volume of the glacier will greatly decrease, which will have great impact on the ecological environment of the upper reach of the Yangtze River.

  2. Mass balance, meteorological, ice motion, surface altitude, and runoff data at Gulkana Glacier, Alaska, 1993 balance year

    Science.gov (United States)

    March, Rod; Trabant, Dennis

    1997-01-01

    The 1993 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier basin were evaluated on the basis of meteorological, hydrological, and glaciological data measured in the basin and are reported herein. Averaged over the glacier, the measured winter snow balance was 0.81 meter on March 31, 1993, 1.2 standard deviations below the long-term average; the maximum winter snow balance, 0.84 meter, was reached on May 10, 1993 and remained until May 11, 1993; the net balance (from August 18, 1992 to September 8, 1993) was 1.80 meters, the most negative balance year on record at 2.8 standard deviations below the long-term average. The annual balance (October 1, 1992 to September 30, 1993) was 1.64 meters. Ice-surface motion and altitude changes measured at three index sites document seasonal ice speed and glacier thickness changes. Annual stream runoff was 1.996 meters averaged over the basin, 0.2 standard deviations above the long-term average.

  3. Primary dispersal of supraglacial debris and debris cover formation on alpine glaciers

    Science.gov (United States)

    Kirkbride, M. P.; Deline, P.

    2009-04-01

    Debris-covered glaciers are receiving increased attention due to the modulation of runoff by supraglacial covers, and to the lake outburst flood hazard at many covered glacier termini. Observed increases in debris cover extents cannot presently be explained in terms of glaciological influences. The supply of englacial debris to the supraglacial zone has previously been understood only in terms of local dispersal due to differential ablation between covered and uncovered ice, for example on medial moraines. Here, we introduce the term primary dispersal to describe the process of migration of the outcrops of angled debris septa across melting, thinning ablation zones. Understanding primary debris dispersal is an essential step to understanding how supraglacial debris cover is controlled by glaciological variables, and hence is sensitive to climatically-induced fluctuation. Three measures of a glacier's ability to evacuate supraglacial debris are outlined: (1) a concentration factor describing the focussing of englacial debris into specific supraglacial mass loads; (2) the rate of migration of a septum outcrop relative to the local ice surface; and (3) a downstream velocity differential between a septum outcrop and the ice surface. (1) and (2) are inversely related, while (3) increases downglacier to explain why slow-moving, thinning ice rapidly becomes debris covered. Data from Glacier d'Estelette (Italian Alps) illustrate primary dispersal processes at a site where debris cover is increasing in common with many other shrinking alpine glaciers. We develop a model of the potential for debris cover formation and growth in different glaciological environments. This explains why glaciers whose termini are obstructed often have steep debris septa feeding debris covers which vary slowly in response to mass balance change. In contrast, at glaciers with gently-dipping debris-bearing foliation, the debris cover extent is sensitive to glaciological change. These findings

  4. Area change of glaciers in the Canadian Rocky Mountains, 1919 to 2006

    Directory of Open Access Journals (Sweden)

    C. Tennant

    2012-12-01

    Full Text Available Glaciers in the Canadian Rocky Mountains constitute an important freshwater resource. To enhance our understanding of the influence climate and local topography have on glacier area, large numbers of glaciers of different sizes and attributes need to be monitored over periods of many decades. We used Interprovincial Boundary Commission Survey (IBCS maps of the Alberta–British Columbia (BC border (1903–1924, BC Terrain Resource Information Management (TRIM data (1982–1987, and Landsat Thematic Mapper (TM and Enhanced Thematic Mapper (ETM+ imagery (2000–2002 and 2006 to document planimetric changes in glacier cover in the central and southern Canadian Rocky Mountains between 1919 and 2006. Over this period, glacier cover in the study area decreased by 590 ± 70 km2 (40 ± 5%, 17 of 523 glaciers disappeared and 124 glaciers fragmented into multiple ice masses. Glaciers smaller than 1.0 km2 experienced the greatest relative area loss (64 ± 8%, and relative area loss is more variable with small glaciers, suggesting that the local topographic setting controls the response of these glaciers to climate change. Small glaciers with low slopes, low mean/median elevations, south to west aspects, and high insolation experienced the largest reduction in area. Similar rates of area change characterize the periods 1919–1985 and 1985–2001; −6.3 ± 0.6 km2 yr−1 (−0.4 ± 0.1% yr−1 and −5.0 ± 0.5 km2 yr−1 (−0.5 ± 0.1% yr−1, respectively. The rate of area loss, however, increased over the period 2001–2006; −19.3 ± 2.4 km2 yr−1 (−2.0 ± 0.2% yr−1. Applying size class-specific scaling factors, we estimate a total reduction in glacier cover in the central and southern Canadian Rocky Mountains for the period 1919–2006 of 750 km2 (30%.

  5. Climate warming and stability of cold hanging glaciers: Lessons from the gigantic 1895 Altels break-off

    CERN Document Server

    Faillettaz, Jerome; Funk, Martin

    2011-01-01

    The Altels hanging glacier broke off on September 11, 1895. The ice volume of this catastrophic rupture was estimated at $\\rm 4.10^6$ cubic meters and is the largest ever observed ice fall event in the Alps. The causes of this collapse are however not entirely clear. Based on previous studies, we reanalyzed this break-off event, with the help of a new numerical model, initially developed by Faillettaz and others (2010) for gravity-driven instabilities. The simulations indicate that a break-off event is only possible when the basal friction at the bedrock is reduced in a restricted area, possibly induced by the storage of infiltrated water within the glacier. Moreover, our simulations reveal a two-step behavior: (i) A first quiescent phase, without visible changes, with a duration depending on the rate of basal changes; (ii) An active phase with a rapid increase of basal motion over a few days. The general lesson obtained from the comparison between the simulations and the available evidence is that visible si...

  6. Increasing mass loss from Greenland's Mittivakkat Gletscher

    DEFF Research Database (Denmark)

    Hasholt, Bent; Mernild, S.H.; Knudsen, N.T.;

    2011-01-01

    Warming in the Arctic during the past several decades has caused glaciers to thin and retreat, and recent mass loss from the Greenland Ice Sheet is well documented. Local glaciers peripheral to the ice sheet are also retreating, but few mass-balance observations are available to quantify...... balance and glacier front fluctuations. We attribute this mass loss primarily to record high mean summer (June–August) temperatures in combination with lower-than-average winter precipitation. Also, we use the 15-yr mass-balance record to estimate present-day and equilibrium accumulation-area ratios...... for the MG. We show that the glacier is significantly out of balance and will likely lose at least 70% of its current area and 80% of its volume even in the absence of further climate changes. Temperature records from coastal stations in Southeast Greenland suggest that recent MG mass losses are not merely...

  7. A global assessment of the societal impacts of glacier outburst floods

    Science.gov (United States)

    Carrivick, Jonathan L.; Tweed, Fiona S.

    2016-09-01

    Glacier outburst floods are sudden releases of large amounts of water from a glacier. They are a pervasive natural hazard worldwide. They have an association with climate primarily via glacier mass balance and their impacts on society partly depend on population pressure and land use. Given the ongoing changes in climate and land use and population distributions there is therefore an urgent need to discriminate the spatio-temporal patterning of glacier outburst floods and their impacts. This study presents data compiled from 20 countries and comprising 1348 glacier floods spanning 10 centuries. Societal impacts were assessed using a relative damage index based on recorded deaths, evacuations, and property and infrastructure destruction and disruption. These floods originated from 332 sites; 70% were from ice-dammed lakes and 36% had recorded societal impact. The number of floods recorded has apparently reduced since the mid-1990s in all major world regions. Two thirds of sites that have produced > 5 floods (n = 32) have floods occurring progressively earlier in the year. Glacier floods have directly caused at least: 7 deaths in Iceland, 393 deaths in the European Alps, 5745 deaths in South America and 6300 deaths in central Asia. Peru, Nepal and India have experienced fewer floods yet higher levels of damage. One in five sites in the European Alps has produced floods that have damaged farmland, destroyed homes and damaged bridges; 10% of sites in South America have produced glacier floods that have killed people and damaged infrastructure; 15% of sites in central Asia have produced floods that have inundated farmland, destroyed homes, damaged roads and damaged infrastructure. Overall, Bhutan and Nepal have the greatest national-level economic consequences of glacier flood impacts. We recommend that accurate, full and standardised monitoring, recording and reporting of glacier floods is essential if spatio-temporal patterns in glacier flood occurrence, magnitude and

  8. Accelerated glacier shrinkage in the Ak-Shyirak massif, Inner Tien Shan, during 2003-2013.

    Science.gov (United States)

    Petrakov, Dmitry; Shpuntova, Alyona; Aleinikov, Alexandr; Kääb, Andreas; Kutuzov, Stanislav; Lavrentiev, Ivan; Stoffel, Markus; Tutubalina, Olga; Usubaliev, Ryskul

    2016-08-15

    The observed increase in summer temperatures and the related glacier downwasting has led to a noticeable decrease of frozen water resources in Central Asia, with possible future impacts on the economy of all downstream countries in the region. Glaciers in the Ak-Shyirak massif, located in the Inner Tien Shan, are not only affected by climate change, but also impacted by the open pit gold mining of the Kumtor Gold Company. In this study, glacier inventories referring to the years 2003 and 2013 were created for the Ak-Shyirak massif based on satellite imagery. The 193 glaciers had a total area of 351.2±5.6km(2) in 2013. Compared to 2003, the total glacier area decreased by 5.9±3.4%. During 2003-2013, the shrinkage rate of Ak-Shyirak glaciers was twice than that in 1977-2003 and similar to shrinkage rates in Tien Shan frontier ranges. We assessed glacier volume in 2013 using volume-area (VA) scaling and GlabTop modelling approaches. Resulting values for the whole massif differ strongly, the VA scaling derived volume is 30.0-26.4km(3) whereas the GlabTop derived volume accounts for 18.8-13.2km(3). Ice losses obtained from both approaches were compared to geodetically-derived volume change. VA scaling underestimates ice losses between 1943 and 2003 whereas GlabTop reveals a good match for eight glaciers for the period 2003-2012. In comparison to radio-echo soundings from three glaciers, the GlabTop model reveals a systematic underestimation of glacier thickness with a mean deviation of 16%. GlabTop tends to significantly underestimate ice thickness in accumulation areas, but tends to overestimate ice thickness in the lowermost parts of glacier snouts. Direct technogenic impact is responsible for about 7% of area and 5% of mass loss for glaciers in the Ak-Shyirak massif during 2003-2013. Therefore the increase of summer temperature seems to be the main driver of accelerated glacier shrinkage in the area. PMID:27100016

  9. A data set of world-wide glacier length fluctuations

    Directory of Open Access Journals (Sweden)

    P. W. Leclercq

    2013-09-01

    Full Text Available Glacier fluctuations contribute to variations in sea level and historical glacier length fluctuations are natural indicators of climate change. To study these subjects, long-term information of glacier change is needed. In this paper we present a~data set of global long-term glacier length fluctuations. The data set is a compilation of available information on changes in glacier length world-wide, including both measured and reconstructed glacier length fluctuations. All 471 length series start before 1950 and cover at least four decades. The longest record starts in 1534, but the majority of time series start after 1850. The number of available records decreases again after 1962. The data set has global coverage including records from all continents. However, the Canadian Arctic is not represented in the data set. The glacier length series show relatively small fluctuations until the mid-19th century followed by a global retreat that was strongest in the first half of the 20th century, although large variability in the length change of the different glaciers is observed. During the 20th century, calving glaciers retreated more than land terminating glaciers, but their relative length change was approximately equal. Besides calving, the glacier slope is the most important glacier property determining length change: steep glaciers have retreated less than glaciers with a gentle slope.

  10. Atmospheric drying as the main driver of dramatic glacier wastage in the southern Indian Ocean

    Science.gov (United States)

    Favier, V.; Verfaillie, D.; Berthier, E.; Menegoz, M.; Jomelli, V.; Kay, J. E.; Ducret, L.; Malbéteau, Y.; Brunstein, D.; Gallée, H.; Park, Y.-H.; Rinterknecht, V.

    2016-09-01

    The ongoing retreat of glaciers at southern sub-polar latitudes is particularly rapid and widespread. Akin to northern sub-polar latitudes, this retreat is generally assumed to be linked to warming. However, no long-term and well-constrained glacier modeling has ever been performed to confirm this hypothesis. Here, we model the Cook Ice Cap mass balance on the Kerguelen Islands (Southern Indian Ocean, 49°S) since the 1850s. We show that glacier wastage during the 2000s in the Kerguelen was among the most dramatic on Earth. We attribute 77% of the increasingly negative mass balance since the 1960s to atmospheric drying associated with a poleward shift of the mid-latitude storm track. Because precipitation modeling is very challenging for the current generation of climate models over the study area, models incorrectly simulate the climate drivers behind the recent glacier wastage in the Kerguelen. This suggests that future glacier wastage projections should be considered cautiously where changes in atmospheric circulation are expected.

  11. Atmospheric drying as the main driver of dramatic glacier wastage in the southern Indian Ocean

    Science.gov (United States)

    Favier, V.; Verfaillie, D.; Berthier, E.; Menegoz, M.; Jomelli, V.; Kay, J. E.; Ducret, L.; Malbéteau, Y.; Brunstein, D.; Gallée, H.; Park, Y.-H.; Rinterknecht, V.

    2016-01-01

    The ongoing retreat of glaciers at southern sub-polar latitudes is particularly rapid and widespread. Akin to northern sub-polar latitudes, this retreat is generally assumed to be linked to warming. However, no long-term and well-constrained glacier modeling has ever been performed to confirm this hypothesis. Here, we model the Cook Ice Cap mass balance on the Kerguelen Islands (Southern Indian Ocean, 49°S) since the 1850s. We show that glacier wastage during the 2000s in the Kerguelen was among the most dramatic on Earth. We attribute 77% of the increasingly negative mass balance since the 1960s to atmospheric drying associated with a poleward shift of the mid-latitude storm track. Because precipitation modeling is very challenging for the current generation of climate models over the study area, models incorrectly simulate the climate drivers behind the recent glacier wastage in the Kerguelen. This suggests that future glacier wastage projections should be considered cautiously where changes in atmospheric circulation are expected. PMID:27580801

  12. Atmospheric drying as the main driver of dramatic glacier wastage in the southern Indian Ocean.

    Science.gov (United States)

    Favier, V; Verfaillie, D; Berthier, E; Menegoz, M; Jomelli, V; Kay, J E; Ducret, L; Malbéteau, Y; Brunstein, D; Gallée, H; Park, Y-H; Rinterknecht, V

    2016-01-01

    The ongoing retreat of glaciers at southern sub-polar latitudes is particularly rapid and widespread. Akin to northern sub-polar latitudes, this retreat is generally assumed to be linked to warming. However, no long-term and well-constrained glacier modeling has ever been performed to confirm this hypothesis. Here, we model the Cook Ice Cap mass balance on the Kerguelen Islands (Southern Indian Ocean, 49°S) since the 1850s. We show that glacier wastage during the 2000s in the Kerguelen was among the most dramatic on Earth. We attribute 77% of the increasingly negative mass balance since the 1960s to atmospheric drying associated with a poleward shift of the mid-latitude storm track. Because precipitation modeling is very challenging for the current generation of climate models over the study area, models incorrectly simulate the climate drivers behind the recent glacier wastage in the Kerguelen. This suggests that future glacier wastage projections should be considered cautiously where changes in atmospheric circulation are expected. PMID:27580801

  13. Photographic Snow-cover Monitoring on St Sorlin Glacier, France.

    Science.gov (United States)

    Gerbaux, M.; Genthon, C.; Dedieu, J.; Balestrieri, J.

    2004-12-01

    Like most other glaciers in the Alps, the St Sorlin glacier (french Alps, 45.16°N, 6.16°E, 2900 m asl mean elevation and 3km2 of surface area) has been retreating fast in the last 20 years. To understand the meteorological factors responsible for this retreat, and to tentatively predict glaciers evolution in a changing (warming) climate, we use a distributed snow/ice mass and energy balance model derived from the CROCUS snow model (Météo-France). There is no direct meteorological observation on or near St Sorlin glacier yet, and hourly meteorology to force the snow/ice model is obtained from disaggregated meteorological analyses. The model is found to reproduce the St Sorlin mass balance of the last 20 years as obtained from field glaciological measurements and stereophotographic reconstructions. The model is also found to reproduce the interannual variations of the equilibrium line as determined from optical satellite imagery. Because of the albedo feedback involved, it is also important to verify that the summer snow/ice transition on the glacier is correctly simulated. Thus, an automated photographic system was set up facing St Sorlin glacier to monitor the evolution of the snow cover. The system was installed on the 13th of July 2004 and is still in operation at time of abstract writing. Digital photographies are taken every 4 hours, permitting so far at least one non-obstructed (rain, fog) picture per day. The first pictures in the series show an almost fully snow-covered glacier while the latest ones show bare ice up to the highest parts of the glacier. Snow is occasionally deposited during precipitation events but hardly last more than 3 days. Snow line position is deduced from pictures using a DEM with georeferenced points visible on pictures. It should then be compared with the modelled one. The automated photographic system provides not only snow cover to check snow/ice model results at seasonal time-scales, but also qualitative meteorological

  14. Role of glaciers in watershed hydrology: a preliminary study of a "Himalayan catchment"

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    R. J. Thayyen

    2010-02-01

    Full Text Available A large number of Himalayan glacier catchments are under the influence of humid climate with snowfall in winter (November–April and south-west monsoon in summer (June–September dominating the regional hydrology. Such catchments are defined as "Himalayan catchment", where the glacier meltwater contributes to the river flow during the period of annual high flows produced by the monsoon. The winter snow dominated Alpine catchments of the Kashmir and Karakoram region and cold-arid regions of the Ladakh mountain range are the other major glacio-hydrological regimes identified in the region. Factors influencing the river flow variations in a "Himalayan catchment" were studied in a micro-scale glacier catchment in the Garhwal Himalaya, covering an area of 77.8 km2. Three hydrometric stations were established at different altitudes along the Din Gad stream and discharge was monitored during the summer ablation period from 1998 to 2004, with an exception in 2002. These data have been analysed along with winter/summer precipitation, temperature and mass balance data of the Dokriani glacier to study the role of glacier and precipitation in determining runoff variations along the stream continuum from the glacier snout to 2360 m a.s.l. The study shows that the inter-annual runoff variation in a "Himalayan catchment" is linked with precipitation rather than mass balance changes of the glacier. This study also indicates that the warming induced an initial increase of glacier runoff and subsequent decline as suggested by the IPCC (2007 is restricted to the glacier degradation-derived component in a precipitation dominant Himalayan catchment and cannot be translated as river flow response. The preliminary assessment suggests that the "Himalayan catchment" could experience higher river flows and positive glacier mass balance regime together in association with strong monsoon. The important role of glaciers in this precipitation dominant system is

  15. Headwall erosion rates from cosmogenic (10) Be in supraglacial debris, Chhota Shigri Glacier, Indian Himalaya

    Science.gov (United States)

    Scherler, Dirk; Egholm, David

    2016-04-01

    Debris-covered glaciers are widespread within the Himalaya and other steep mountain ranges. They testify to active erosion of ice-free bedrock hillslopes that tower above valley glaciers, sometimes more than 1 km high. It is long known that debris cover significantly reduces surface ablation rates and thereby influences glacial mass balances; but its dynamic evolution along with climatic and topographic changes is poorly studied. Better understanding the coupling of ice-free bedrock hillslopes and glaciers in steep mountains requires means to assess headwall erosion rates. Here, we present headwall erosion rates derived from 10Be concentrations in the ablation-dominated medial moraine of the Chhota Shigri Glacier, Indian Himalaya. We combine our empirical, field-based approach with a numerical model of headwall erosion and glacial debris transport to assess permissible patterns of headwall erosion on the ice-free bedrock hillslopes surrounding the Chhota Shigri Glacier. Our five samples, each separated by approximately 500 m along the glacier, consist of an amalgamation of >1000 surface clasts with grain sizes between ˜1 and ˜30 mm that were taken from the medial moraine. Our results show that 10Be concentrations increase downglacier from ˜3×104 to ˜6×104 atoms g‑1, yielding headwall erosion rates of ˜1.3-0.6 mm yr‑1. The accumulation of 10Be during debris residence on the ice surface can only account for a small fraction (cracking, e.g., spatially uniform versus temperature dependent.

  16. Himalayan glaciers: understanding contrasting patterns of glacier behavior using multi-temporal satellite imagery

    Science.gov (United States)

    Racoviteanu, A.

    2014-12-01

    High rates of glacier retreat for the last decades are often reported, and believed to be induced by 20th century climate changes. However, regional glacier fluctuations are complex, and depend on a combination of climate and local topography. Furthermore, in ares such as the Hindu-Kush Himalaya, there are concerns about warming, decreasing monsoon precipitation and their impact on local glacier regimes. Currently, the challenge is in understanding the magnitude of feedbacks between large-scale climate forcing and small-scale glacier behavior. Spatio-temporal patterns of glacier distribution are still llimited in some areas of the high Hindu-Kush Himalaya, but multi-temporal satellite imagery has helped fill spatial and temporal gaps in regional glacier parameters in the last decade. Here I present a synopsis of the behavior of glaciers across the Himalaya, following a west to east gradient. In particular, I focus on spatial patterns of glacier parameters in the eastern Himalaya, which I investigate at multi-spatial scales using remote sensing data from declassified Corona, ASTER, Landsat ETM+, Quickbird and Worldview2 sensors. I also present the use of high-resolution imagery, including texture and thermal analysis for mapping glacier features at small scale, which are particularly useful in understanding surface trends of debris-covered glaciers, which are prevalent in the Himalaya. I compare and contrast spatial patterns of glacier area and élévation changes in the monsoon-influenced eastern Himalaya (the Everest region in the Nepal Himalaya and Sikkim in the Indian Himalaya) with other observations from the dry western Indian Himalaya (Ladakh and Lahul-Spiti), both field measurements and remote sensing-based. In the eastern Himalaya, results point to glacier area change of -0.24 % ± 0.08% per year from the 1960's to the 2006's, with a higher rate of retreat in the last decade (-0.43% /yr). Debris-covered glacier tongues show thinning trends of -30.8 m± 39 m

  17. An enhanced temperature index model for debris-covered glaciers accounting for thickness effect

    Science.gov (United States)

    Carenzo, M.; Pellicciotti, F.; Mabillard, J.; Reid, T.; Brock, B. W.

    2016-08-01

    strem curve. Its large number of parameters might be a limitation, but we show that the model is transferable in time and space to a second glacier with little loss of performance. We thus suggest that the new DETI model can be included in continuous mass balance models of debris-covered glaciers, because of its limited data requirements. As such, we expect its application to lead to an improvement in simulations of the debris-covered glacier response to climate in comparison with models that simply recalibrate empirical parameters to prescribe a constant across glacier reduction in melt.

  18. 水文气象学方法计算喜马拉雅山北坡冰川流域物质平衡%Computation on the Mass Balance of Glaciers in North Himalaya with a Hydro-meteorological Method

    Institute of Scientific and Technical Information of China (English)

    汪奎奎; 刘景时; 巩同梁; 田克明; 卢巍

    2009-01-01

    The Karuxung catchment is a typical and unique area with a long term observations in the Tibet-Himalayas since 1983. A group of expressions, which can be used to calculate the mass balance of glacier based on hydrological and meteorological observation data, could been deduced according to the glacier hydrology and climate characteristics of the distribution in China. Using the conceptual method, the components of the mass balance of the glaciers in the Karuxung from 1983 to 2006 has been estimated. The result shows that: in the 24 years, the glaciers in Karuxung area is turning to retreat more quickly; the averaged mass balance for 24 years was - 136. 3 mm/a. It was -83.61 mm/a in the first 12 years (from 1983 to 1994), and reduces to - 188.98 mm/a in the last 12 years ( from 1995 to 2006). The mass balance of glacier presents a greater fluctuation in 1986,1998 and 2005 respectively, with numbers of 149. 19 mm, -654. 36 mm and -316. 43 ram. After analyzing the reason of the change of the mass balance of the glaciers, it was found that the main reason was the average temperature of May to September.There was linear correlations between the mass balance of the glaciers and the average temperature , and the correlations coefficients reached to -0. 786.%卡鲁雄曲是喜马拉雅that坡唯一具有长期常规水文气象观测资料的冰川流域.根据中国冰川水文和气候的分布特征,可推导出一组以水文、气象观测数据计算流域冰川平均物质平衡的公式.据此恢复了1983-2006年卡鲁雄曲流域冰川平均物质平衡各分量的逐年值序列,并用SPSS软件对计算结果进行r统计分析.结果表明:1983-2006年的24 a里,卡鲁雄曲流域的冰川消融逐步加剧:多年平均值为-136.3 mm/a,前12 a(1983-1994年)多年平均值为-83.61 mm/a,后12 a(1995-2006年)多年平均值为-188.98 mm/a,且1986、1998和2005年出现较大的波动,冰川物质平衡值分别为:149.19mm、-654.36 mm和-316.43 mm.通过对

  19. The impact of glacier retreat from the Ross Sea on local climate: Characterization of mineral dust in the Taylor Dome ice core, East Antarctica

    Science.gov (United States)

    Aarons, S. M.; Aciego, S. M.; Gabrielli, P.; Delmonte, B.; Koornneef, J. M.; Wegner, A.; Blakowski, M. A.

    2016-06-01

    Recent declines in ice shelf and sea ice extent experienced in polar regions highlight the importance of evaluating variations in local weather patterns in response to climate change. Airborne mineral particles (dust) transported through the atmosphere and deposited on ice sheets and glaciers in Antarctica and Greenland can provide a robust set of tools for resolving the evolution of climatic systems through time. Here we present the first high time resolution radiogenic isotope (strontium and neodymium) data for Holocene dust in a coastal East Antarctic ice core, accompanied by rare earth element composition, dust concentration, and particle size distribution during the last deglaciation. We aim to use these combined ice core data to determine dust provenance, with variations indicative of shifts in either dust production, sources, and/or transport pathways. We analyzed a series of 17 samples from the Taylor Dome (77°47‧47″S, 158°43‧26″E) ice core, 113-391 m in depth from 1.1-31.4 ka. Radiogenic isotopic and rare earth element compositions of dust during the last glacial period are in good agreement with previously measured East Antarctic ice core dust records. In contrast, the Holocene dust dataset displays a broad range in isotopic and rare earth element compositions, suggesting a shift from long-range transported dust to a more variable, local input that may be linked to the retreat of the Ross Ice Shelf during the last deglaciation. Observed changes in the dust cycle inferred from a coastal East Antarctic ice core can thus be used to infer an evolving local climate.

  20. Volcano-Ice Interactions in Mexico: Extinction of Glaciers at Popocatépetl and the Fate of the Glaciers of Iztaccíhuatl and Citlaltépetl Volcanoes

    Science.gov (United States)

    Delgado Granados, H.

    2007-05-01

    In spite of the state of activity of the Mexican volcanoes (erupting, fumarolic, or dormant) study of volcano-ice interactions is of key importance because one of the main consequences of these interactions is the generation of lahars. Study of glaciers and volcanic activity help to prevent the possibility of devastating events at volcanoes in Mexico, especially because some explosive events at Popocatépetl volcano generated lahars during the past twelve years. Small-sized glaciers exist or existed at Iztaccíhuatl, Popocatépetl and Citlaltépetl whose volcanic activity is characterized by a different level of activity. The extinction of glaciers of Popocatépetl volcano was eruption-forced. 40% of climatic-related shrinkage occurred in 4 decades whereas 32% of eruption-related shrinkage occurred in 4 years. Long-term effects of glacier extinction include an imbalance between recharge and extraction of groundwater at surrounding aquifers provoked by disappearance of glacier-related melt water. The volcano started to erupt in 1994. Impact of the eruption on the glaciers was in several ways: immediate thermal effect of hot falling ash on snow and ice.; ballistic projectiles are also hot and yield high kinetic energy producing melting restricted to the impact areas; every event depositing 1cm of ash represents a load of ~102-104 tons; fumaroles of effect is difficult to assess. Iztaccíhuatl volcano's glaciers have been influenced by the same factors as at Popocatépetl, except the eruption. Citlaltépetl volcano's glaciers have been just affected by climatic changes. Both volcanoes show fumaroles or diffuse degassing. An eruptive event in the short term may cause the same effect as occurred at Popocatépetl volcano. The large ice masses of the world are claimed to be affected by global warming and local climatic variations. Tropical glaciers as those of Mexico are more vulnerable because of their size and exposure to eruptive processes. Even though their extinction

  1. Processes driving rapid morphological changes observed on the Khumbu Glacier, Nepal

    Science.gov (United States)

    Quincey, Duncan; Rowan, Ann; Gibson, Morgan; Irvine-Fynn, Tristram; King, Owen; Watson, Scott

    2016-04-01

    The response of many Himalayan glaciers to climatic change is complicated by the presence of a supraglacial debris cover, which leads to a suite of processes controlling mass loss that are not commonly found where glaciers are debris-free. Here, we present a range of field, surface topographic and ice-dynamical observations acquired from Khumbu Glacier in Nepal, to describe and quantify these processes in fine spatial and temporal resolution. Like many other debris-covered glaciers in the Himalaya, the debris-covered tongue of the Khumbu Glacier is heavily in recession. For at least two decades, the lower ablation area has been stagnant as surface lowering in the mid-ablation zone has led to ever decreasing driving stresses. Contemporary velocity data derived from TerraSAR-X imagery confirms that the active-inactive ice boundary can now be found 5 km from the glacier terminus and that the maximum velocity, immediately below the icefall, is around 70 m per year. These data show that in this upper part of the ablation zone, the glacier velocity has not changed during the last 20 years, suggesting that at least above the icefall the glacier remains healthy. Across the stagnant debris-covered tongue there have been marked surface morphological changes. Mapping from 2004 shows relatively few surface ponds, a homogeneous debris-covered surface, and a small area towards the terminus supporting soil formation and low vegetation. Mapping from field observations in 2014 shows an abundance of surface meltwater, a more heterogeneous surface texture associated with many exposed ice cliffs, and a long (3 km) zone of stable terrain where soils are developing and, in places, low scrub can be found. Most dramatically, a string of surface ponds occupying the true-left lowermost 2 km of ice have expanded and coalesced, suggesting the glacier has crossed a threshold leading towards large glacial lake development. Two fine-resolution DEMs derived from Structure-from-Motion in spring

  2. Climate modelling of mass-extinction events: a review

    Science.gov (United States)

    Feulner, Georg

    2009-07-01

    Despite tremendous interest in the topic and decades of research, the origins of the major losses of biodiversity in the history of life on Earth remain elusive. A variety of possible causes for these mass-extinction events have been investigated, including impacts of asteroids or comets, large-scale volcanic eruptions, effects from changes in the distribution of continents caused by plate tectonics, and biological factors, to name but a few. Many of these suggested drivers involve or indeed require changes of Earth's climate, which then affect the biosphere of our planet, causing a global reduction in the diversity of biological species. It can be argued, therefore, that a detailed understanding of these climatic variations and their effects on ecosystems are prerequisites for a solution to the enigma of biological extinctions. Apart from investigations of the paleoclimate data of the time periods of mass extinctions, climate-modelling experiments should be able to shed some light on these dramatic events. Somewhat surprisingly, however, only a few comprehensive modelling studies of the climate changes associated with extinction events have been undertaken. These studies will be reviewed in this paper. Furthermore, the role of modelling in extinction research in general and suggestions for future research are discussed.

  3. Modeling debris-covered glaciers: extension due to steady debris input

    Directory of Open Access Journals (Sweden)

    L. S. Anderson

    2015-11-01

    Debris-forced glacier extension decreases the ratio of accumulation zone to total glacier area (AAR. The model reproduces first-order relationships between debris cover, AARs, and glacier surface velocities from glaciers in High Asia. We provide a quantitative, theoretical foundation to interpret the effect of debris cover on the moraine record, and to assess the effects of climate change on debris-covered glaciers.

  4. Brief communication: Historical glacier length changes in West Greenland

    Directory of Open Access Journals (Sweden)

    P. W. Leclercq

    2012-08-01

    Full Text Available Past glacier fluctuations provide insight into glacier dynamics, climate change, and the contribution of glaciers to sea-level rise. Here, the length fluctuations since the 19th century of 18 local glaciers in West and South Greenland are presented, extending and updating the study by Weidick (1968. The studied glaciers all show an overall retreat with an average of 1.2 ± 0.2 km over the 20th century, indicating a general rise of the equilibrium line along the west coast of Greenland during the last century. The rate of retreat was largest in the first half of the 20th century.

  5. Brief communication "Historical glacier length changes in West Greenland"

    Directory of Open Access Journals (Sweden)

    P. W. Leclercq

    2012-11-01

    Full Text Available Past glacier fluctuations provide insight into glacier dynamics, climate change, and the contribution of glaciers to sea-level rise. Here, the length fluctuations since the 19th century of 18 local glaciers in West and South Greenland are presented, extending and updating the study by Weidick (1968. The studied glaciers all showed an overall retreat with an average of 1.2 ± 0.2 km over the 20th century, indicating a general rise of the equilibrium line along the west coast of Greenland during the last century. Furthermore, the average rate of retreat was largest in the first half of the 20th century.

  6. Area change of glaciers in the Canadian Rocky Mountains, 1919 to 2006

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    C. Tennant

    2012-07-01

    Full Text Available We used Interprovincial Boundary Commission Survey (IBCS maps of the Alberta–British Columbia (BC border (1903–1924, BC Terrain Resource Information Management (TRIM data (1982–1987, and Landsat Thematic Mapper (TM and Enhanced Thematic Mapper (ETM+ imagery (2000–2002 and 2006 to document planimetric changes in glacier cover in the Central and Southern Canadian Rocky Mountains between 1919 and 2006. Total glacierized area decreased by 590 ± 100 km2 (40 ± 7%, with 17 of 523 glaciers disappearing and 124 glaciers fragmenting into multiple ice masses. Fourteen of the glaciers that disappeared were less than 0.5 km2, and glaciers smaller than 1.0 km2 experienced the greatest relative area loss (64 ± 17%. Variation in area loss increased with small glaciers, suggesting local topographic setting controls the response of these glaciers to climate change. Absolute area loss negatively correlates with slope and minimum elevation, and relative area change negatively correlates with mean and median elevations. Similar average rates of area change were observed for the periods 1919–1985 and 1985–2001, at −6.3 ± 0.9 km2 yr−1 (−0.4 ± 0.1% yr−1 and −5.0 ± 0.5 km2 yr−1 (−0.3 ± 0.1% yr−1, respectively. The rate of area loss significantly increased for the period 2001–2006, −19.3 ± 2.4 km2 yr−1 (−1.3 ± 0.2% yr−1, with continued high minimum and accumulation season temperature anomalies and variable precipitation anomalies.

  7. Glacier and climate changes in the Western Indian Himalayas (Ladakh and Lahul-Spiti): remote sensing, field techniques and adaptation techniques

    Science.gov (United States)

    Racoviteanu, Adina; Williams, Mark

    2010-05-01

    Anecdotal evidence from glacier termini observations in the Himalayas suggest that these glaciers have been in a state of general retreat since the last century, and point to "alarming" rates of retreat in the past decades. Concomitantly, local communities in the Western Himalayas have reported changes in glacier extents, snow cover and weather patterns. In response to "alarming" rates of glacial retreat, some indigenous cultures in the Himalayan area have begun a number of adaptive responses such as meltwater harvesting to construct "artificial" glaciers, which store the water during the dry season. There is urgency in: a) scientifically evaluating whether such practices of glacier regeneration can help provide water in a timely manner and 2) developing glacier datasets to assist such local efforts to ensure water supply in these data-scarce mountainous areas. Here we compare and contrast scientific and indigenous perspectives on spatial patterns of glacier changes in the dry areas of Ladakh (34.10°N and 77.34°E ) and Lahul-Spiti district (31.11°N and 77.15°E ) in the Western Indian Himalaya. A new glacier inventory of Lahul-Spiti was constructed using a combination of data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor with Shuttle Radar Topography Mission (SRTM), GPS field data and ground photography. Glacier changes were quantified by comparison with older ASTER inventory and topographic maps. We present changes reported by local communities and recorded in video, oral testimonies and ground photography. We focus on two indigenous practices of water harvesting for glacier regeneration: a) artificial glaciers and b) kul irrigation systems. Field data of artificial glaciers was acquired at Sabu, Stakmo and Phuktsey glaciers using a differential GPS system. Kul irrigation systems were documented in Spiti valley (Lara and Kibber villages). We will present the results of mapping these water harvesting systems with the goal

  8. Modelling the advance–retreat cycle of a tidewater glacier with simple sediment dynamics

    NARCIS (Netherlands)

    Oerlemans, J.; Nick, Faezeh Maghami

    2006-01-01

    We present a simple coupled glacier-sediment model to simulate the evolution of a tidewater glacier. The model is based on a consideration of the total mass budget of a glacier, whereas ice mechanics are fully parameterized. The calving rate at the glacier terminus is assumed to be proportional to t

  9. Anthropogenic climate change impacts on ponds: a thermal mass perspective

    Directory of Open Access Journals (Sweden)

    John Matthews

    2010-12-01

    Full Text Available Small freshwater aquatic lentic systems (lakes and ponds are sensitive to anthropogenic climate change through shifts in ambient air temperatures and patterns of precipitation. Shifts in air temperatures will influence lentic water temperatures through convection and by changing evaporation rates. Shifts in the timing, amount, and intensity of precipitation will alter the thermal mass of lentic systems even in the absence of detectable ambient air temperature changes. These effects are likely to be strongest in ponds (standing water bodies primarily mixed by temperature changes than by wind, for whom precipitation makes up a large component of inflows. Although historical water temperature datasets are patchy for lentic systems, thermal mass effects are likely to outweigh impacts from ambient air temperatures in most locations and may show considerable independence from those trends. Thermal mass-induced changes in water temperature will thereby alter a variety of population- and community-level processes in aquatic macroinvertebrates.

  10. The archives of the glacier survey of the Austrian Alpine Club

    Science.gov (United States)

    Fischer, Andrea; Bendler, Gebhard

    2016-04-01

    The archive of the Austrian Alpine Club holds masses of material on glaciers and their former extent. The material includes descriptions and sketches of the summits conquered by early mountaineers, mapping campaigns and data from early scientific expeditions as well as data on glacier length change. To date a large proportion of the glaciological information in the material has not been catalogued or analysed. As cold ice, containing relevant climate information, might still exist at the highest peaks of Austria, a pilot project was started to collect some of the data of two test sites in Tyrol, in Silvretta and Ötztal Alps, to reveal former summit shapes and glacier tongue positions. Additional information on the number and position of crevasses as well as firn extent is often evident from the material. Challenging tasks not yet tackled are compiling a catalogue of the material and defining an analysis scheme.

  11. A Revised Glacier Inventory of Bhaga Basin Himachal Pradesh, India : Current Status and Recent Glacier Variations

    Science.gov (United States)

    Birajdar, F.; Venkataraman, G.; Bahuguna, I.; Samant, H.

    2014-11-01

    Himalayan glaciers show large uncertainty regarding their present and future state due to their sensitive reaction towards change in climatic condition. Himalayan glaciers are unique as they are located in tropical, high altitude regions, predominantly valley type and many are covered with debris. The great northern plains of India sustain on the perennial melt of glaciers meeting the water requirements of agriculture, industries, domestic sector even in the months of summer when large tracts of the country go dry. Therefore, it is important to monitor and assess the state of snow and glaciers and to know the sustainability of glaciers in view of changing global scenarios of climate and water security of the nation. Any information pertaining to Himalayan glaciers is normally difficult to be obtained by conventional means due to its harsh weather and rugged terrains. Due to the ecological diversity and geographical vividness, major part of the Indian Himalaya is largely un-investigated. Considering the fact that Himalayan glaciers are situated in a harsh environment, conventional techniques of their study is challenging and difficult both in terms of logistics and finances whereas the satellite remote sensing offers a potential mode for monitoring glaciers in long term. In order to gain an updated overview of the present state of the glacier cover and its changes since the previous inventories, an attempt has been made to generate a new remotesensing- derived glacier inventory on 1:50,000 scale for Bhaga basin (N32°28'19.7'' - N33°0'9.9'' ; E76°56'16.3'' - E77°25'23.7'' ) Western Himalaya covering an area of 1695.63 km2. having 231 glaciers and occupying glacierized area of 385.17 ±3.71 km2. ranging from 0.03 km2. to 29.28 km2. Glacier inventory has been carried out using high resolution IRS P6 LISS III data of 2011, ASTER DEM and other ancillary data. Specific measurements of mapped glacier features are the inputs for generating the glacier inventory data

  12. GLACIER and related R&D

    CERN Document Server

    Curioni, Alessandro

    2011-01-01

    Liquid argon detectors, with mass up to 100 kton, are being actively studied in the context of proton decay searches, neutrino astrophysics and for the next generation of long baseline neutrino oscillation experiments to study the neutrino mass hierarchy and CP violation in the leptonic sector. The proposed Giant Liquid Argon Charge Imaging ExpeRiment (GLACIER) offers a well defined conceptual design for such a detector. In this paper we present the GLACIER design and some of the R&D activities pursued within the GLACIER.

  13. ICESat laser altimetry over small mountain glaciers

    Science.gov (United States)

    Treichler, Désirée; Kääb, Andreas

    2016-09-01

    Using sparsely glaciated southern Norway as a case study, we assess the potential and limitations of ICESat laser altimetry for analysing regional glacier elevation change in rough mountain terrain. Differences between ICESat GLAS elevations and reference elevation data are plotted over time to derive a glacier surface elevation trend for the ICESat acquisition period 2003-2008. We find spatially varying biases between ICESat and three tested digital elevation models (DEMs): the Norwegian national DEM, SRTM DEM, and a high-resolution lidar DEM. For regional glacier elevation change, the spatial inconsistency of reference DEMs - a result of spatio-temporal merging - has the potential to significantly affect or dilute trends. Elevation uncertainties of all three tested DEMs exceed ICESat elevation uncertainty by an order of magnitude, and are thus limiting the accuracy of the method, rather than ICESat uncertainty. ICESat matches glacier size distribution of the study area well and measures small ice patches not commonly monitored in situ. The sample is large enough for spatial and thematic subsetting. Vertical offsets to ICESat elevations vary for different glaciers in southern Norway due to spatially inconsistent reference DEM age. We introduce a per-glacier correction that removes these spatially varying offsets, and considerably increases trend significance. Only after application of this correction do individual campaigns fit observed in situ glacier mass balance. Our correction also has the potential to improve glacier trend significance for other causes of spatially varying vertical offsets, for instance due to radar penetration into ice and snow for the SRTM DEM or as a consequence of mosaicking and merging that is common for national or global DEMs. After correction of reference elevation bias, we find that ICESat provides a robust and realistic estimate of a moderately negative glacier mass balance of around -0.36 ± 0.07 m ice per year. This regional

  14. Surface Albedo Variation and Its Influencing Factors over Dongkemadi Glacier, Central Tibetan Plateau

    OpenAIRE

    Jie Wang; Yuhuan Cui; Xiaobo He; Jian Zhang; Shijiang Yan

    2015-01-01

    Glacier albedo plays a critical role in surface-atmosphere energy exchange, the variability of which influences glacier mass balance as well as water resources. Dongkemadi glacier in central Tibetan Plateau was selected as study area; this research used field measurements to verify Landsat TM-derived albedo and MOD10A1 albedo product and then analyzed the spatiotemporal variability of albedo over the glacier according to them, as well as its influence factors and the relationship with glacier...

  15. 'Unlocking the archive': Using digital photogrammetry of modern and historic aerial photography to reconstruct 60 years of volumetric change on the Moider Glacier, Antarctic Peninsula

    Science.gov (United States)

    Clarke, Lucy; Miller, Pauline; Ireland, Louise; Fox, Adrian; Mills, Jon; Fieber, Karolina

    2016-04-01

    The Antarctic Peninsula is a mountain glacier system comprised of over 400 glaciers, and is an important contributor to historical and future sea level rise. Assessment and monitoring of AP glaciers is crucial for understanding sensitivity to climate change. Changes to glacier fronts and ice shelves and glacier acceleration are well documented, but there are almost no data on mass changes on the Antarctic Peninsula. Satellite data have been used to calculate change over the last 3 decades, but methods to quantify this over longer timescales have eluded researchers. However there is an archive of aerial photography dating back to the 1940s, this has been largely ignored due to the range of technical problems associated with deriving quantitative data from historic imagery and the lack of ground control data. This presentation demonstrates how advances in photogrammetric processing and capture of modern aerial photography has allowed this archive to be 'unlocked'. Accurate photogrammetric reconstruction from aerial photographs traditionally requires known ground control points acquired in the field; in remote and inaccessible areas, such as the Antarctic Peninsula, this is often impossible. A method for providing control for historic photos without fieldwork, by linking them to a newly acquired, highly accurate photogrammetric model adjusted through direct kinematic GPS positioning of the camera has been applied to a number of glaciers across the Antarctic Peninsula. This presentation will outline the photogrammetric workflow with focus on the Moider Glacier in the Marguerite Bay region of the western Antarctic Peninsula to investigate the quality of data that can be obtained. Volumetric changes on the glaciers from the 1950s to present day (2015) have been reconstructed and can be used to explore the spatial and temporal changes that have occurred on this glacier. In particular, there is near-annual data over the last 5 years recording a period when there has been

  16. Glacier Photograph Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Glacier Photograph Collection is a database of photographs of glaciers from around the world, some dating back to the mid-1850's, that provide an historical...

  17. World Glacier Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Glacier Inventory (WGI) contains information for over 130,000 glaciers. Inventory parameters include geographic location, area, length, orientation,...

  18. Glaciers between two drivers

    DEFF Research Database (Denmark)

    Machguth, Horst

    2014-01-01

    It is assumed that the monsoon is the dominant influence on Himalayan glaciers. However, a study now investigates the importance of the mid-latitude Westerlies and shows that glacier changes can be triggered from afar....

  19. Modeling debris-covered glaciers: response to steady debris deposition

    OpenAIRE

    Anderson, Leif S.; Anderson, Robert S.

    2016-01-01

    Debris-covered glaciers are common in rapidly eroding alpine landscapes. When thicker than a few centimeters, surface debris suppresses melt rates. If continuous debris cover is present, ablation rates can be significantly reduced leading to increases in glacier length. In order to quantify feedbacks in the debris–glacier–climate system, we developed a 2-D long-valley numerical glacier model that includes englacial and supraglacial debris advection. We ran 120 si...

  20. Representing moisture fluxes and phase changes in glacier debris cover using a single-reservoir approach

    Science.gov (United States)

    Collier, E.; Nicholson, L. I.; Brock, B. W.; Maussion, F.; Essery, R.; Bush, A. B. G.

    2014-03-01

    Due to the complexity of treating moisture in supraglacial debris, surface energy balance models to date have neglected moisture infiltration and phase changes in the debris layer. The latent heat flux (QL) is also often excluded due to the uncertainty in determining the surface vapour pressure. To quantify the importance of moisture on the surface energy and climatic mass balance (CMB) of debris-covered glaciers, we developed a simple, single-reservoir parameterization for the debris ice and water content, as well as an estimation of the latent heat flux. The parameterization was incorporated into a sophisticated CMB model adapted for debris-covered glaciers. We perform two point simulations using both our new "moist" and the conventional "dry" approaches, on the Miage Glacier, Italy, during summer 2008 and fall 2011. The former simulation coincides with available in situ glaciological and meteorological measurements, including the first eddy-covariance measurements of the turbulent fluxes over supraglacial debris, while the latter contains two refreeze events that permit evaluation of the influence of phase changes. The simulations demonstrate a clear influence of moisture on the glacier energy and mass dynamics. Heat transmission to the underlying ice is lower, as the effective thermal diffusivity of the debris is reduced by increases in the weighted density and specific heat capacity when water and ice are considered. In combination with surface heat extraction by QL, sub-debris ice melt is reduced by 2.3% in 2008 and by 2.8% in 2011 when moisture effects are included. However, mass loss due to surface vapour fluxes more than compensates for the reduction in ice melt, such that the total accumulated ablation increased by 5.3% in 2008 and by 2.8% in 2011. Although the parameterization is a simplified representation of the moist physics of glacier debris, it is a novel attempt at including moisture in a numerical model of debris-covered glaciers and opens up

  1. Glaciers in Patagonia: Controversy and prospects

    Science.gov (United States)

    Kargel, J. S.; Alho, P.; Buytaert, W.; Célleri, R.; Cogley, J. G.; Dussaillant, A.; Guido, Z.; Haeberli, W.; Harrison, S.; Leonard, G.; Maxwell, A.; Meier, C.; Poveda, G.; Reid, B.; Reynolds, J.; Rodríguez, C. A. Portocarrero; Romero, H.; Schneider, J.

    2012-05-01

    Lately, glaciers have been subjects of unceasing controversy. Current debate about planned hydroelectric facilities—a US7- to 10-billion megaproject—in a pristine glacierized area of Patagonia, Chile [Romero Toledo et al., 2009; Vince, 2010], has raised anew the matter of how glaciologists and global change experts can contribute their knowledge to civic debates on important issues. There has been greater respect for science in this controversy than in some previous debates over projects that pertain to glaciers, although valid economic motivations again could trump science and drive a solution to the energy supply problem before the associated safety and environmental problems are understood. The connection between glaciers and climate change—both anthropogenic and natural—is fundamental to glaciology and to glaciers' practical importance for water and hydropower resources, agriculture, tourism, mining, natural hazards, ecosystem conservation, and sea level [Buytaert et al., 2010; Glasser et al., 2011]. The conflict between conservation and development can be sharper in glacierized regions than almost anywhere else. Glaciers occur in spectacular natural landscapes, but they also supply prodigious exploitable meltwater.

  2. Measuring the mass balance and contribution to sea level rise of North American glaciers using remote sensing techniques

    Science.gov (United States)

    Vanlooy, Jeffrey Adam

    Volume and surface elevation changes were calculated for six icefields throughout Alaska and British Columbia by differencing Digital Elevation Models (DEMs) that represent glacial elevations from different time periods. For the Harding Icefield on the Kenai Peninsula in southcentral Alaska, United States Geological Survey (USGS) DEMs from the 1950s were differenced with Shuttle Radar Topographic Mission (SRTM) DEMs from 2000 (effective 1999 elevations). Results indicated that the icefield had a volume loss of -72.1 +/-15.0 km3, which equates to 0.0033 +/- 0.0006 mm y-1 of sea level rise contribution. Along with these results, Light Detecting and Ranging (Lidar) elevation data of 13 Harding Icefield glaciers from the mid-1990s provided a third elevation data set for comparison with the USGS and SRTM DEMs. The results from these surface elevation change calculations indicated that surface elevation change rates increased by 1.5 times from the mid-1990s to 1999 (-0.72 +/- 0.13 m y-1) as compared to the 1950s to the mid-1900s (-0.47 +/- 0.01 m y-1). In southwest British Columbia, five icefields were studied: Monarch, Ha-Iltzuk, Mt. Waddington area, Homathko, and Lillooet. Terrain Resource Information Management (TRIM) DEMs from the mid-1980s were differenced from the SRTM DEMs to calculate the volume and surface elevation change of the five icefields. Results from these calculations indicate that between the mid-1980s and 1999 the total volume change of the five icefields was a loss of -47.72 +/- 14.62 km3, which equates to a potential sea level rise contribution of 0.0077 +/-0.0021 mm y-1. A DEM of a third time period was produced by kriging elevation points derived from 1970s topographic maps, and used to calculate volume and surface elevation changes of Ha-Iltzuk Icefield for the time period of 1970 to the mid-1980s. The results of this analysis indicate that Ha-Iltzuk Icefield had a volume loss of -5.87 +/- 2.89 km3 and a surface elevation change rate of -0

  3. Ice flux divergence anomalies on 79north Glacier, Greenland

    DEFF Research Database (Denmark)

    Seroussi, H.; Morlighem, M.; Rignot, E.;

    2011-01-01

    The ice flux divergence of a glacier is an important quantity to examine because it determines the rate of temporal change of its thickness. Here, we combine high-resolution ice surface velocity observations of Nioghalvfjerdsfjorden (79north) Glacier, a major outlet glacier in north Greenland......, with a dense grid of ice thickness data collected with an airborne radar sounder in 1998, to examine its ice flux divergence. We detect large variations, up to 100 m/yr, in flux divergence on grounded ice that are incompatible with what we know of the glacier surface mass balance, basal mass balance...... onto a regular grid using a scheme (here block kriging) that does not conserve mass or ice flux. This problem is not unique to 79north Glacier but is common to all conventional ice thickness surveys of glaciers and ice sheets; and fundamentally limits the application of ice thickness grids to high...

  4. Evaluating Tourist Perception of Environmental Changes as a Contribution to Managing Natural Resources in Glacierized Areas: A Case Study of the Forni Glacier (Stelvio National Park, Italian Alps)

    Science.gov (United States)

    Garavaglia, Valentina; Diolaiuti, Guglielmina; Smiraglia, Claudio; Pasquale, Vera; Pelfini, Manuela

    2012-12-01

    Climate change effects are noticeably evident above the timberline where glacier and permafrost processes and mass movements drive the surface evolution. In particular, the cryosphere shrinkage is deeply changing the features and characteristics of several glacierized mountain areas of the world, and these modifications can also affect the landscape perception of tourists and mountaineers. On the one hand glacier retreat is increasing the interest of tourists and visitors in areas witnessing clear climate change impacts; on the other hand cryosphere shrinkage can impact the touristic appeal of mountain territories which, diminishing their ice and snow coverage, are also losing part of their aesthetic value. Then, to promote glacierized areas in a changing climate and to prepare exhaustive and actual proposals for sustainable tourism, it is important to deepen our knowledge about landscape perception of tourists and mountaineers and their awareness of the ongoing environmental modifications. Here we present the results from a pilot study we performed in summer 2009 on a representative glacierized area of the Alps, the Forni Valley (Stelvio National Park, Lombardy, Italy), a valley shaped by Forni, the largest Italian valley glacier. During the 2009 summer season we asked tourists visiting the Forni Valley to complete a questionnaire. This study was aimed at both describing the features and characteristics of tourists and mountaineers visiting this Alpine zone in summer and evaluating their landscape perception and their ability to recognize climate change impacts and evidence. Our results suggest that the dissemination strategies in a natural protected area have to take into account not only the main landscape features but also the sites where the information will be given. In particular considering the peculiarities of the huts located in the area, such as their different accessibility and the fact that they are included or not in a mountaineering network like that

  5. How much water will glaciers in the Chon Kemin valley (Tien Shan mountains, Kyrgyzstan) provide in the future?

    Science.gov (United States)

    Sorg, Annina; Huss, Matthias; Stoffel, Markus

    2013-04-01

    2005), which might indicate that the Chon Kemin River already underwent a transformation from a glacial-nival to a nival-pluvial runoff regime. To quantify future runoff from Chon Kemin River, we use the glacio-hydrological model GERM. The model includes transient glacier changes and calculates glacier mass balance and runoff in daily time-steps. The refined multi-variable-calibration allows a realistic reproduction of each runoff component and an accurate simulation of discharge and mass balance over time. Calibration and validation include snowcover duration from MODIS/AVHRR (1985-2012), mass balance data from Tuyuksu glacier in the neighboring valley (1957-2009), changes in glacier extent and surface elevation from aerial photographs (1956 and 1988), glacier length changes (1977-1990) and measured daily runoff (1936-2005). After calibration, the model is run with daily precipitation and temperature data from a downscaled regional climate model (IPCC scenario A1B) until the end of the 21st century. In order to produce realistic results, we address uncertainties in terms of amount, seasonal distribution and form of future precipitation in detail, as well as feedback mechanisms, such as a changing snow cover.

  6. Sensitivity and Response of Bhutanese Glaciers to Atmospheric Warming

    Science.gov (United States)

    Rupper, Summer; Schaefer, Joerg M.; Burgener, Landon K.; Koenig, Lora S.; Tsering, Karma; Cook, Edward

    2013-01-01

    Glacierized change in the Himalayas affects river-discharge, hydro-energy and agricultural production, and Glacial Lake Outburst Flood potential, but its quantification and extent of impacts remains highly uncertain. Here we present conservative, comprehensive and quantitative predictions for glacier area and meltwater flux changes in Bhutan, monsoonal Himalayas. In particular, we quantify the uncertainties associated with the glacier area and meltwater flux changes due to uncertainty in climate data, a critical problem for much of High Asia. Based on a suite of gridded climate data and a robust glacier melt model, our results show that glacier area and meltwater change projections can vary by an order of magnitude for different climate datasets. However, the most conservative results indicate that, even if climate were to remain at the present-day mean values, almost 10% of Bhutan s glacierized area would vanish and the meltwater flux would drop by as much as 30%. Under the conservative scenario of an additional 1 C regional warming, glacier retreat is going to continue until about 25% of Bhutan s glacierized area will have disappeared and the annual meltwater flux, after an initial spike, would drop by as much as 65%. Citation

  7. Monte Carlo modelling projects the loss of most land-terminating glaciers on Svalbard in the 21st century under RCP 8.5 forcing

    Science.gov (United States)

    Möller, Marco; Navarro, Francisco; Martín-Español, Alba

    2016-09-01

    The high Arctic archipelagos around the globe are among the most strongly glacierized landscapes on Earth apart from the Greenland and Antarctic ice sheets. Over the past decades, the mass losses from land ice in the high Arctic regions have contributed substantially to global sea level rise. Among these regions, the archipelago of Svalbard showed the smallest mass losses. However, this could change in the coming decades, as Svalbard is expected to be exposed to strong climate warming over the 21st century. Here we present extensive Monte Carlo simulations of the future ice-mass evolution of 29 individual land-terminating glaciers on the Svalbard archipelago under an RCP 8.5 climate forcing. An extrapolation of the 29 sample glaciers to all land-terminating glaciers of the archipelago suggests an almost complete deglaciation of the region by 2100. Under RCP 8.5, 98% of the land-terminating glaciers will have declined to less than one tenth of their initial size, resulting in a loss of 7392 ± 2481 km2 of ice coverage.

  8. Study on climate change in Southwestern China

    International Nuclear Information System (INIS)

    Nominated by Chinese Academy of Sciences as an outstanding Ph.D. thesis. Offers a needed exploration of the temporal and spatial pattern of climate change in southwestern China. Explores the action mechanism among the large-scale atmospheric circulation system, the complicated topography, human activities and regional climate changes. Analyzes the response of glaciers to climate change from the aspects of morphology of the glacier, glacial mass balance and the process of hydrology. This thesis confirms many changes, including sharp temperature rise, interannual variability of precipitation, extreme climate events and significant decreases of sunshine duration and wind speed in southwestern China, and systemically explores the action mechanism between large-scale atmospheric circulation systems, the complicated topography, human activities and regional climate changes. This study also analyzes the response of glaciers to climate change so that on the one hand it clearly reflects the relationship between glacier morphologic changes and climate change; on the other, it reveals the mechanism of action of climate warming as a balance between energy and matter. The achievements of this study reflect a significant contribution to the body of research on the response of climate in cold regions, glaciers and human activities to a global change against the background of the typical monsoon climate, and have provided scientific basis for predictions, countermeasures against disasters from extreme weather, utilization of water and the establishment of counterplans to slow and adapt to climate change. Zongxing Li works at the Cold and Arid Region Environmental and Engineering Research Institute, Chinese Academy of Sciences, China.

  9. Study on climate change in Southwestern China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zongxing

    2015-03-01

    Nominated by Chinese Academy of Sciences as an outstanding Ph.D. thesis. Offers a needed exploration of the temporal and spatial pattern of climate change in southwestern China. Explores the action mechanism among the large-scale atmospheric circulation system, the complicated topography, human activities and regional climate changes. Analyzes the response of glaciers to climate change from the aspects of morphology of the glacier, glacial mass balance and the process of hydrology. This thesis confirms many changes, including sharp temperature rise, interannual variability of precipitation, extreme climate events and significant decreases of sunshine duration and wind speed in southwestern China, and systemically explores the action mechanism between large-scale atmospheric circulation systems, the complicated topography, human activities and regional climate changes. This study also analyzes the response of glaciers to climate change so that on the one hand it clearly reflects the relationship between glacier morphologic changes and climate change; on the other, it reveals the mechanism of action of climate warming as a balance between energy and matter. The achievements of this study reflect a significant contribution to the body of research on the response of climate in cold regions, glaciers and human activities to a global change against the background of the typical monsoon climate, and have provided scientific basis for predictions, countermeasures against disasters from extreme weather, utilization of water and the establishment of counterplans to slow and adapt to climate change. Zongxing Li works at the Cold and Arid Region Environmental and Engineering Research Institute, Chinese Academy of Sciences, China.

  10. Observations of enhanced thinning in the upper reaches of Svalbard glaciers

    Directory of Open Access Journals (Sweden)

    T. D. James

    2012-11-01

    Full Text Available Changes in the volume and extent of land ice of the Svalbard archipelago have been the subject of considerable research since their sensitivity to changes in climate was first noted. However, the measurement of these changes is often necessarily based on point or profile measurements which may not be representative if extrapolated to a whole catchment or region. Combining high-resolution elevation data from contemporary laser-altimetry surveys and archived aerial photography makes it possible to measure historical changes across a glacier's surface without the need for extrapolation. Here we present a high spatial resolution time-series for six Arctic glaciers in the Svalbard archipelago spanning 1961 to 2005. We find high variability in thinning rates between sites with prevalent elevation changes at all sites averaging −0.59 ± 0.04 m a−1 between 1961–2005. Prior to 1990, ice surface elevation was changing at an average rate of −0.52 ± 0.09 m a−1 which decreased to −0.76 ± 0.10 m a−1 after 1990. Setting the elevation changes against the glaciers' altitude distribution reveals that significant increases in thinning rates are occurring most notably in the glaciers' upper reaches. We find that these changes are coincident with a decrease in winter precipitation at the Longyearbyen meteorological station and could reflect a decrease in albedo or dynamic response to lower accumulation. Further work is required to understand fully the causes of this increase in thinning rates in the glaciers' upper reaches. If on-going and occurring elsewhere in the archipelago, these changes will have a significant effect on the region's future mass balance. Our results highlight the importance of understanding the climatological context of geodetic mass balance measurements and demonstrate the difficulty of using index glaciers to represent regional changes in areas of strong climatological gradients.

  11. Bridging glacier and river catchment scales: an efficient representation of glacier dynamics in a hydrological model

    OpenAIRE

    Wortmann, Michel; Bolch, Tobias; Krysanova, Valentina; Buda, Su

    2016-01-01

    Glacierised river catchments have been shown to be highly sensitive to climate change, while large populations depend on the water resources originating from them. Hydrological models are used to aid water resource management, yet their treatment of glacier processes is either rudimentary in large applications or linked to fully distributed glacier models that prevent larger model domains. Also, data scarcity in mountainous catchments has hampered the implementation of physically based approa...

  12. Glacier dynamics and subsurface classification of Austfonna, Svalbard: : Inferences from observations and modelling

    OpenAIRE

    2011-01-01

    Ice loss from glaciers and ice caps in the Arctic constitute a major contribution to eustatic sea-level rise. Climate change is more pronounced in the Arctic than in other regions, because strong feedback mechanisms such as the albedo feedback lead to enhancement of the initial warming trend. Glaciers and ice caps serve as valuable indicators of past and present climate. However, extraction of climate signals from glaciers is not straightforward. The history, current state and future evolutio...

  13. Motion of the Lambert Glacier estimated by using differential Interferometric Synthetic Aperture Radar

    International Nuclear Information System (INIS)

    Interferometric Synthetic Aperture Radar (InSAR) is one of the most promising remote sensing technologies and has been widely applied in constructing topographic information and estimating the deformation of the Earth's surface. Ice velocity is an important parameter for calculating the mass balance and modelling ice shelve dynamics. Ice velocity is also an important indicator for climate changes. Therefore, it plays an important role in studying the global climate change and global sea level rise. In this paper, the ERS-1/2 tandem data and the ASTER GDEM are combined together to obtained the deformation in line of sight by using the differential Interferometric SAR for the Lambert Amery glacier in Antarctica. Then the surface parallel assumption is adopted in order to achieve the ice flow velocity. The results showed that ice velocity would be increased along the Lambert glacier; the maximum ice velocity would be reach about 450m/year in the study area

  14. Progresses in the ice formation of glaciers in China

    Institute of Scientific and Technical Information of China (English)

    Xiangying LI; Shiyin LIU; ,Donghui SHANGGUAN1; Aigang LU

    2008-01-01

    Glaciers,formed by snowfall and characterized by movement and size,are the most sensitive indicators to climate change.The ice formation of glaciers(the processes,mechanisms and results of transformation from snow to ice)can indicate the growth condition,the formation process and the physical characteristics of glaciers.Its spatial variation can also reflect glacier change,and further reveal climate change.Studies on ice formation of glaciers in China were initiated in 1962,when Xie and others studied the ice formation of Glacier No.1 at the Urumqi River head,Tianshan Mountain.Other researchers followed suit and did studies on ice formation of glaciers in Qilian Mountain.As time goes by,the concept of ice formation came into being in China.This paper reviews the development history of glacier zones,and the studies of ice formation of glaciers in China since the 1960s.These studies mainly focus on Qilian Mountain,Tianshan Mountain,Altay Mountain,and the western Kunlun Mountain,Himalaya Mountain,the southeastern Tibetan and Hengduan Mountains.The paper also discusses the significance of ice formation studies,the limitation and deficiency of previous studies,and the prospects and suggestions for future studies.

  15. Glacier contribution to streamflow in two headwaters of the Huasco River, Dry Andes of Chile

    OpenAIRE

    Gascoin, S.; C. Kinnard; R. Ponce; S. Lhermitte; MacDonell, S; A. Rabatel

    2010-01-01

    Quantitative assessment of glacier contribution to present-day streamflow is a prerequisite to the anticipation of climate change impact on water resources in the Dry Andes. In this paper we focus on two glaciated headwater catchments of the Huasco Basin (Chile, 29° S). The combination of glacier monitoring data for five glaciers (Toro 1, Toro 2, Esperanza, Guanaco, Estrecho and Ortigas) with five automatic streamflow records at sites with glacier coverage of 0.4 to 11% allows the estimation ...

  16. Modelled glacier equilibrium line altitudes during the mid-Holocene in the southern mid-latitudes

    Science.gov (United States)

    Bravo, C.; Rojas, M.; Anderson, B. M.; Mackintosh, A. N.; Sagredo, E.; Moreno, P. I.

    2015-11-01

    Glacier behaviour during the mid-Holocene (MH, 6000 years BP) in the Southern Hemisphere provides observational data to constrain our understanding of the origin and propagation of palaeoclimate signals. In this study we examine the climatic forcing of glacier response in the MH by evaluating modelled glacier equilibrium line altitudes (ELAs) and climatic conditions during the MH compared with pre-industrial time (PI, year 1750). We focus on the middle latitudes of the Southern Hemisphere, specifically Patagonia and the South Island of New Zealand. Climate conditions for the MH were obtained from PMIP2 model simulations, which in turn were used to force a simple glacier mass balance model to simulate changes in ELA. In Patagonia, the models simulate colder conditions during the MH in austral summer (-0.2 °C), autumn (-0.5 °C), and winter (-0.4), and warmer temperatures (0.2 °C) during spring. In the Southern Alps the models show colder MH conditions in autumn (-0.7 °C) and winter (-0.4 °C), warmer conditions in spring (0.3 °C), and no significant change in summer temperature. Precipitation does not show significant changes but exhibits a seasonal shift, with less precipitation from April to September and more precipitation from October to April during the MH in both regions. The mass balance model simulates a climatic ELA that is 15-33 m lower during the MH compared with PI conditions. We suggest that the main causes of this difference are driven mainly by colder temperatures associated with the MH simulation. Differences in temperature have a dual effect on glacier mass balance: (i) less energy is available for ablation during summer and early autumn and (ii) lower temperatures cause more precipitation to fall as snow rather than rain in late autumn and winter, resulting in more accumulation and higher surface albedo. For these reasons, we postulate that the modelled ELA changes, although small, may help to explain larger glacier extents observed by 6000

  17. Arctic glacier movement monitoring with GPS method on 2005

    Institute of Scientific and Technical Information of China (English)

    Ai Songtao; E Dongchen; Yan Ming; Ren Jiawen

    2006-01-01

    During the 2005 Arctic Yellow River Station expedition, the research on monitoring the movement and mass balance of two glaciers around Ny-Alesund,Station expedition were conducted. This paper analyzes the feasibility and advantage in using GPS method to monitor the Arctic glaciers'movement, estimates the precision of first time measured GPS data and discusses the relevant problems in surveying on the Arctic Glaciers with GPS.

  18. Hydrological interaction between glacier and páramos in the tropical Andes: implications for water resources availability

    Science.gov (United States)

    Villacís, Marcos; Cadier, Eric; Mena, Sandra; Anaguano, Marcelo; Calispa, Marlon; Maisisncho, Luis; Galárraga, Remigio; Francou, Bernard

    2010-05-01

    Preliminary hydro glacier estimates indicate that glacier contribution to the average annual consumption (5.6 m3 s-1) of the city of Quito (Capital of Ecuador, ~2'500.000 inhabitants, 2800 masl) represents only about 2%-4% of the total supply for human consumption. However, at the local level at the Antizana volcano (0°28'S, 78°09'W), the mass balance analysis of the system composed by the Humboldt catchment (area of 15.1 km2, 15% of glaciarized area, 5% of moraines area, 80% of the area is páramo-endemic ecosystem of the tropical Andes, range from 5670 masl to 4000 masl) and Los Crespos catchment (area of 2.4 km2, 67% glaciarized area, 27% moraines area, range from 5670 masl to 4500 masl), which is nested into the Humboldt catchment, allows us to identify that due to the presence of the glacier reservoirs there is an additional contribution of 24% to the annual volume at the Humboldt catchment and it helps to regulate the runoff during the dry season, where the daily additional glacier contribution from November to February in some cases could reach t 40%. The Humboldt catchment has similar physiographic characteristics than the sites where new diversions will be built in the future in order to satisfy the increasing demand of water for human consumption of the city of Quito and its surrounding populations. Based on detail hydrological observations (every 15 minutes measurements) during 2005 to 2009 and sporadic environmental trace analysis during the same period, the annual percentage of glacier contribution from the Humboldt catchment could potentially be as high as 37% due in part to the glacier melt contribution that gets infiltrated over 4750 masl it is then delivered around 4100 masl through underground circulation. Some of the sites where the glacier contribution reaches de surface has been identified through field work and the glacier origin of this water have been confirmed using a conductivity measurement, which seems to be a good indicator in when

  19. From Theory to Practice: How Mass Audubon Is Incorporating Strategic Framing about Climate Change

    Science.gov (United States)

    Fleischer, Amy

    2013-01-01

    Mass Audubon recognized that climate change was significantly impacting bird species distribution and seasonality. Unsure of how and when to engage visitors to their network of wildlife sanctuaries on the topic of climate change, its educators turned to the National Network of Ocean and Climate Change Interpreters' Study Circle (NNOCCI). Through…

  20. Ocean and glaciers interactions in Svalbard area

    Science.gov (United States)

    Walczowski, Waldemar; Błaszczyk, Małgorzata; Wawrzyniak, Tomasz; Beszczyńska-Möller, Agnieszka

    2016-04-01

    Arctic fjords are a link between land and ocean. The inshore boundary of the fjords system is usually dominated by the tidewater glaciers and seasonal freshwater input while its offshore boundary is strongly influenced by oceanic waters. Improved understanding of the fjords-ocean exchange and processes within Arctic fjords is of a highest importance because their response to atmospheric, oceanic and glacial variability provides a key to understand the past and to forecast the future of the high latitude glaciers and Arctic climate. Rapidly changed Arctic climate requires multidisciplinary and complex investigations of the basic climate components and interactions between them. The aim of the Polish-Norwegian project 'Arctic climate system study of ocean, sea ice and glaciers interactions in Svalbard area' (AWAKE-2) is to understand the interactions between the ocean, atmosphere and cryosphere. The main oceanic heat source in Svalbard region is the West Spitsbergen Current consisting of multi-branch, northward flow of warm, Atlantic origin water (AW). During its transit through the Nordic Seas, AW releases a large amount of heat to the atmosphere. When entering the Western Svalbard fjords, AW modifies hydrographic conditions, reduces winter ice cover and directly influences tidewater glaciers. An impact of the AW variability on atmosphere and sea ice is clearly visible with strong correlations between AW properties and air temperature or sea ice coverage. For tidewater glaciers these effects can be recognized, but correlations are weaker due to different processes that influence the intensity of glaciers melting and calving. The dedicated, multidisciplinary approach was adopted to achieve the AWAKE-2 project's aims by carrying out the coordinated meteorological, oceanographic, glaciological and geophysical observations in the Hornsund fjord, the adjacent shelf and ocean.

  1. Glaciers and hydrological changes in the Tien Shan: simulation and prediction

    Energy Technology Data Exchange (ETDEWEB)

    Aizen, V B [Department of Geography, University of Idaho, Moscow, ID 83844-3025 (United States); Aizen, E M [Department of Geography, University of Idaho, Moscow, ID 83844-3025 (United States); Kuzmichonok, V A [Institute of Water Problems and Hydro Power, Kyrgyz National Academy of Science, 533 Frunze Street, Bishkek 720033 (Kyrgyzstan)

    2007-10-15

    In this study, we estimated the current glacier state and forecast the potential impact of global and regional climate change on the glaciers and glacier runoff in the Tien Shan. General (G) and detailed (D) simulations were developed based on assessment of the Tien Shan glacier recession between 1943 and 2003 using an iterative stepwise increase in the equilibrium line altitude of 20 m. The G simulation was developed for 2777 grids each of which covered over 1000 km{sup 2} of glacier surface and D for the 15 953 Tien Shan glaciers. Both simulations employed glacier morphometric characteristics derived from Digital Elevation Model based on remote sensing data, high resolution maps and in situ GPS validation. Simulated changes in glacier area demonstrated that a possible increase in air temperature of 1 deg. C at E-barLA must be compensated by a 100 mm increase in precipitation at the same altitude if Tien Shan glaciers are to be maintained in their current state. An increase in mean air temperature of 4 deg. C and precipitation of 1.1 times the current level could increase E-barLA by 570 m during the 21st century. Under these conditions, the number of glaciers, glacier covered area, glacier volume, and glacier runoff are predicted to be 94%, 69%, 75%, and 75% of current values. The maximum glacier runoff may reach as much as 1.25 times current levels while the minimum will likely equal zero.

  2. Satellite monitoring of glaciers in the Karakoram from 1977 to 2013: an overall almost stable population of dynamic glaciers

    Directory of Open Access Journals (Sweden)

    R. M. Brahmbhatt

    2015-03-01

    Full Text Available Six hundred and seven glaciers of the Shigar, Shashghan, Nubra and part of Shyok sub-basins of the Karakoram region were monitored using satellite data of years 1977, 1990, 2000, 2001, 2002, 2004, 2006, 2008, 2009, 2010, 2011 and 2013. Landsat MSS, TM, ETM+ and IRS/Resourcesat-1 LISS III data were used. Glacier observations were classified into 3 categories such as advance, retreat or stable with reference to base data of 1977. Glaciers of the Karakoram have shown inconsistency in advance, retreat and no change during this period, and some examples of glacier surging have been caught in action. Despite significant geographic and temporal variability betraying the dynamic nature of many of the glaciers, in aggregate the population is roughly stable with less propensity toward retreat than most other glaciers in the nearby Himalaya and in the world. 341 glaciers exhibited no measured change throughout the 36 years of the study. Among other glaciers, no significant and sustained pattern of retreat or advance was observed. The overall changes in glacier area in the whole region are of small magnitudes (positive and negative values in the various measured intervals. Moreover, it is mostly disconnected glaciers in tributary valleys which have advanced, whereas the main former trunk glaciers have primarily not changed. The dynamical differences between disconnected former tributaries and trunks may be related to response time differences, with the smaller, perhaps steeper tributaries responding more rapidly than trunks to brief climatic fluctuations. The advance/retreat fluctuations of many individual glaciers suggest that their response times primarily may be of order decades rather than some longer period, though some glaciers may have longer response times that have limited their length and area changes over the 36 year study period. The data from 2001 onwards were also utilized for finding annual changes of glaciers. Among the 607 glaciers, 10 show

  3. Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002

    Science.gov (United States)

    Zwally, H. Jay; Li, Jun; Benner, Anita C.; Beckley, Matthew; Cornejo, Helen G.; DiMarzio, John; Giovinetto, Mario B.; Neumann, Thomas A.; Robbins, John; Saba, Jack L.; Yi, Donghui; Wang, Weili

    2011-01-01

    We derive mass changes of the Greenland ice sheet (GIS) for 2003-07 from ICESat laser altimetry and compare them with results for 1992-2002 from ERS radar and airborne laser altimetry. The GIS continued to grow inland and thin at the margins during 2003 07, but surface melting and accelerated flow significantly increased the marginal thinning compared with the 1990s. The net balance changed from a small loss of 7 plus or minus 3 Gt a 1(sup -1) in the 1990s to 171 plus or minus 4 Gt a (sup -1) for 2003-07, contributing 0.5 mm a(sup -1) to recent global sea-level rise. We divide the derived mass changes into two components: (1) from changes in melting and ice dynamics and (2) from changes in precipitation and accumulation rate. We use our firn compaction model to calculate the elevation changes driven by changes in both temperature and accumulation rate and to calculate the appropriate density to convert the accumulation-driven changes to mass changes. Increased losses from melting and ice dynamics (17-206 Gt a(sup-1) are over seven times larger than increased gains from precipitation (10 35 Gt a(sup-1) during a warming period of approximately 2 K (10 a)(sup -1) over the GIS. Above 2000m elevation, the rate of gain decreased from 44 to 28 Gt a(sup-1), while below 2000m the rate of loss increased from 51 to 198 Gt a(sup-1). Enhanced thinning below the equilibrium line on outlet glaciers indicates that increased melting has a significant impact on outlet glaciers, as well as accelerating ice flow. Increased thinning at higher elevations appears to be induced by dynamic coupling to thinning at the margins on decadal timescales.

  4. Hydrological modelling of alpine headwaters using centurial glacier evolution, snow and long-term discharge dynamics

    Science.gov (United States)

    Kohn, Irene; Vis, Marc; Freudiger, Daphné; Seibert, Jan; Weiler, Markus; Stahl, Kerstin

    2016-04-01

    The response of alpine streamflows to long-term climate variations is highly relevant for the supply of water to adjacent lowlands. A key challenge in modelling high-elevation catchments is the complexity and spatial variability of processes, whereas data availability is rather often poor, restricting options for model calibration and validation. Glaciers represent a long-term storage component that changes over long time-scales and thus introduces additional calibration parameters into the modelling challenge. The presented study aimed to model daily streamflow as well as the contributions of ice and snow melt for all 49 of the River Rhine's glaciated headwater catchments over the long time-period from 1901 to 2006. To constrain the models we used multiple data sources and developed an adapted modelling framework based on an extended version of the HBV model that also includes a time-variable glacier change model and a conceptual representation of snow redistribution. In this study constraints were applied in several ways. A water balance approach was applied to correct precipitation input in order to avoid calibration of precipitation; glacier area change from maps and satellite products and information on snow depth and snow covered area were used for the calibration of each catchment model; and finally, specific seasonal and dynamic aspects of discharge were used for calibration. Additional data like glacier mass balances were used to evaluate the model in selected catchments. The modelling experiment showed that the long-term development of the coupled glacier and streamflow change was particularly important to constrain the model through an objective function incorporating three benchmarks of glacier retreat during the 20th Century. Modelling using only streamflow as calibration criteria had resulted in disproportionate under and over estimation of glacier retreat, even though the simulated and observed streamflow agreed well. Also, even short discharge time

  5. Holocene glacier variability and Neoglacial hydroclimate at Ålfotbreen, western Norway

    Science.gov (United States)

    Gjerde, Marthe; Bakke, Jostein; Vasskog, Kristian; Nesje, Atle; Hormes, Anne

    2016-02-01

    Glaciers and small ice caps respond rapidly to climate perturbations (mainly winter precipitation, and summer temperature), and the mass-balance of glaciers located in western Norway is governed mainly by winter precipitation (Pw). Records of past Pw can offer important insight into long-term changes in atmospheric circulation, but few proxies are able to accurately capture winter climate variations in Scandinavia. Reconstructions of equilibrium-line-altitude (ELA) variations from glaciers that are sensitive to changes in Pw therefore provide a unique opportunity to quantify past winter climate in this region. Here we present a new, Holocene glacier activity reconstruction for the maritime ice cap Ålfotbreen in western Norway, based on investigations of distal glacier-fed lake sediments and modern mass balance measurements (1963-2010). Several lake sediment cores have been subject to a suite of laboratory analyses, including measurements of physical parameters such as dry bulk density (DBD) and loss-on-ignition (LOI), geochemistry (XRF), surface magnetic susceptibility (MS), and grain size distribution, to identify glacial sedimentation in the lake. Both radiocarbon (AMS 14C) and 210Pb dating were applied to establish age-depth relationships in the sediment cores. A novel approach was used to calibrate the sedimentary record against a simple ELA model, which allowed reconstruction of continuous ELA changes for Ålfotbreen during the Neoglacial (when Ålfotbreen was present, i.e. the last ∼1400 years). Furthermore, the resulting ELA variations were combined with an independent summer temperature record to calculate Neoglacial Pw using the 'Liestøl equation'. The resulting Pw record is of higher resolution than previous reconstructions from glaciers in Norway and shows the potential of glacier records to provide high-resolution data reflecting past variations in hydroclimate. Complete deglaciation of the Ålfotbreen occurred ∼9700 cal yr BP, and the ice cap was

  6. Integrated firn elevation change model for glaciers and ice caps

    Science.gov (United States)

    Saß, Björn; Sauter, Tobias; Braun, Matthias

    2016-04-01

    We present the development of a firn compaction model in order to improve the volume to mass conversion of geodetic glacier mass balance measurements. The model is applied on the Arctic ice cap Vestfonna. Vestfonna is located on the island Nordaustlandet in the north east of Svalbard. Vestfonna covers about 2400 km² and has a dome like shape with well-defined outlet glaciers. Elevation and volume changes measured by e.g. satellite techniques are becoming more and more popular. They are carried out over observation periods of variable length and often covering different meteorological and snow hydrological regimes. The elevation change measurements compose of various components including dynamic adjustments, firn compaction and mass loss by downwasting. Currently, geodetic glacier mass balances are frequently converted from elevation change measurements using a constant conversion factor of 850 kg m‑³ or the density of ice (917 kg m‑³) for entire glacier basins. However, the natural conditions are rarely that static. Other studies used constant densities for the ablation (900 kg m‑³) and accumulation (600 kg m‑³) areas, whereby density variations with varying meteorological and climate conditions are not considered. Hence, each approach bears additional uncertainties from the volume to mass conversion that are strongly affected by the type and timing of the repeat measurements. We link and adapt existing models of surface energy balance, accumulation and snow and firn processes in order to improve the volume to mass conversion by considering the firn compaction component. Energy exchange at the surface is computed by a surface energy balance approach and driven by meteorological variables like incoming short-wave radiation, air temperature, relative humidity, air pressure, wind speed, all-phase precipitation, and cloud cover fraction. Snow and firn processes are addressed by a coupled subsurface model, implemented with a non-equidistant layer

  7. Investigating glacial mass balance variability around the Prince Gustav Channel

    Science.gov (United States)

    Royston, Samantha; Gudmundsson, Hilmar; Clarke, Lucy; Fox, Adrian

    2015-04-01

    Glaciers on the Antarctic Peninsula have shown a varied response to recent climatic change. Most commonly, AP tidewater glaciers have retreated at the calving front and their flow rate has accelerated, increasing the contribution to sea level rise. Here, we utilise the results from a new photogrammetric technique that unlocks the archives of aerial photography from the 1940's to present, to investigate the driving mechanisms of glacier mass change on the AP over this period. Surface DEMs at different epochs have been derived using the new technique for a number of individual glacier basins. A higher-order vertically-integrated ice stream model is used to investigate the driving mechanisms of change for the area around the Prince Gustav Channel, incorporating basins covered by the new datasets. The Prince Gustav Ice Shelf collapsed in January 1995, followed by significant frontal retreat and speed up of its tributary glaciers. Additionally, significant changes have been observed for non-tributary glaciers such as Whisky Glacier on James Ross Island. Here, we investigate the sensitivity of this region's glaciers to ice shelf collapse, atmospheric and oceanic variability.

  8. Quantification of Seasonal and Interannual Variability of Proglacial Meltwater from a Tidewater Glacier

    Science.gov (United States)

    Darlington, E. F.; Hodgkins, R.; Jenkins, A.

    2014-12-01

    Ice - ocean interactions of tidewater glaciers remain poorly understood; yet 39% of the global glaciated area drains directly into the ocean via tidewater glaciers. As the Arctic cryosphere continues to lose mass in response to a warming climate, more detailed observations are needed to increase our understanding of ice - ocean processes, enabling improved model predictions of Arctic change. Svalbard hosts a high proportion of tidewater glaciers, including Kronebreen, the fastest flowing glacier on the archipelago. The proglacial meltwater exiting the base of Kronebreen transports fine grained sediment to Kongsfjorden, entrained in a buoyant plume which spreads laterally and is visible at the surface. In-situ measurements of the concentration and spectral reflectance of these surface sediments were used to calibrate spectral data from the MODIS instruments on the Terra and Aqua satellites. Temperature and salinity in front of the calving face, and throughout the meltwater plume, have been measured using a hand held CTD. The spatial surface pattern of total suspended sediment (TSS; g l-1) and plume area, has been quantified for every cloud free day between 1st June - 30th September from 2002 - 2013. High TSS sediment during the early melt season indicates flushing, whilst sediment exhaustion is apparent at the end. We show that the areal extent of these proglacial plumes responds to atmospheric temperature, with a 12 day lag. An underlying seasonal evolution of plume extent is apparent; plume area is small at the beginning and end of the melt season, peaking mid-July. Wind speed and direction also play a role in dictating the length of plume formation, with katabatic winds originating from the glacier, lengthening plumes. However, the overall extent of the sediment plume is dependent on meltwater inputs. As such, this method enables the daily to interannual quantification of proglacial meltwater release from tidewater glaciers, utilizing remote sensing.

  9. Glacier topography and elevation changes from Pléiades very high resolution stereo images

    Directory of Open Access Journals (Sweden)

    E. Berthier

    2014-09-01

    Full Text Available In response to climate change, most glaciers are losing mass and hence contribute to sea-level rise. Repeated and accurate mapping of their surface topography is required to estimate their mass balance and to extrapolate/calibrate sparse field glaciological measurements. In this study we evaluate the potential of Pléiades sub-meter stereo imagery to derive digital elevation models (DEMs of glaciers and their elevation changes. Our five validation sites are located in Iceland, the European Alps, the Central Andes, Nepal and Antarctica. For all sites, nearly simultaneous field measurements were collected to evaluate the Pléiades DEMs. For Iceland, the Pléiades DEM is also compared to a Lidar DEM. The vertical biases of the Pléiades DEMs are less than 1 m if ground control points (GCPs are used, but reach up to 6 m without GCPs. Even without GCPs, vertical biases can be reduced to a few decimetres by horizontal and vertical co-registration of the DEMs to reference altimetric data on ice-free terrain. Around these biases, the vertical precision of the Pléiades DEMs is ±1 m and even ±0.5 m on the flat glacier tongues (1-sigma confidence level. We also demonstrate the high potential of Pléiades DEMs for measuring seasonal, annual and multi-annual elevation changes with an accuracy of 1 m or better. The negative glacier-wide mass balances of the Argentière Glacier and Mer de Glace (−1.21 ± 0.16 and −1.19 ± 0.16 m.w.e. yr−1, respectively are revealed by differencing SPOT5 and Pléiades DEMs acquired in August 2003 and 2012 demonstrating the continuing rapid glacial wastage in the Mont-Blanc area.

  10. Reconstruction of the 1979–2006 Greenland ice sheet surface mass balance using the regional climate model MAR

    Directory of Open Access Journals (Sweden)

    X. Fettweis

    2007-10-01

    Full Text Available Results from a 28-year simulation (1979–2006 over the Greenland ice sheet (GrIS reveal an increase of solid precipitation (+0.4±2.5 km3 yr−2 and run-off (+7.9±3.3 km3 yr−2 of surface meltwater. The net effect of these competing factors is a significant Surface Mass Balance (SMB loss of −7.2±5.1 km3 yr−2. The contribution of changes in the net water vapour flux (+0.02±0.09 km3 yr−2 and rainfall (+0.2±0.2 km3 yr−2 to the SMB variability is negligible. The meltwater supply has increased because the GrIS surface has been warming up +2.4°C since 1979. Sensible heat flux, latent heat flux and net solar radiation have not varied significantly over the last three decades. However, the simulated downward infrared flux has increased by 9.3 W m−2 since 1979. The natural climate variability (e.g. the North Atlantic Oscillation does not explain these changes. The recent global warming, due to the greenhouse gas concentration increase induced by human activities, could be a cause of these changes. The doubling of surface meltwater flux into the ocean over the period 1979–2006 suggests that the overall ice sheet mass balance has been increasingly negative, given the likely meltwater-induced acceleration of outlet glaciers. This study suggests that increased melting overshadows over an increased accumulation in a warming scenario and that the GrIS is likely to keep losing mass in the future. An enduring GrIS melting will probably affect in the future an certain effect on the stability of the thermohaline circulation and the global sea level rise.

  11. Reconstruction of the 1979–2006 Greenland ice sheet surface mass balance using the regional climate model MAR

    Directory of Open Access Journals (Sweden)

    X. Fettweis

    2007-07-01

    Full Text Available Results from a 28-year simulation (1979–2006 over the Greenland ice sheet (GIS reveal an increase of the solid precipitation (+0.4±2.5 km3 yr−2 and the run-off (+7.9±3.3 km3 yr−2 of surface melt water. The net effect of these competing factors leads to a significant Surface Mass Balance (SMB loss rate of −7.2±5.1 km3 yr−2. The contribution of changes in the net water vapour fluxes (+0.02±0.09 km3 yr−2 and rainfall (+0.2±0.2 km3 yr−2 to the SMB variability is negligible. The melt water supply has increased because the GIS surface has been warming up +2.4°C since 1979. Latent heat flux, sensible heat flux and net solar radiation have not varied significantly over the last three decades. However, the simulated downward infra-red flux has increased by 9.3 W m−2 since 1979. The natural climate variability (e.g. the North Atlantic Oscillation does not explain these changes on the GIS. The recent global warming, due to the greenhouse gas concentration increase induced by the human activities, could be a cause of these changes. The doubling of the surface melt water flux into the ocean over the period 1979–2006 suggests that the overall ice sheet mass balance has been increasingly negative, given the probable meltwater-induced outlet glacier acceleration. This study suggests that an increased melting dominates over an increased accumulation in a warming scenario and that the GIS would likely continue to loose mass in the future. A GIS melting would have an effect on the stability of the thermohaline circulation (THC and the global sea level rise.

  12. Glacier dynamics at Helheim and Kangerdlugssuaq glaciers, southeast Greenland, since the Little Ice Age

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas; Kjeldsen, Kristian Kjellerup; Kjær, Kurt H.;

    2014-01-01

    Observations over the past decade show significant ice loss associated with the speed-up of glaciers in southeast Greenland from 2003, followed by a deceleration from 2006. These short-term, episodic, dynamic perturbations have a major impact on the mass balance on the decadal scale. To improve...... to the end of the Little Ice Age (prior to 1930) shows no thinning of Helheim Glacier from its maximum extent during the Little Ice Age to 1981, while Kangerdlugssuaq Glacier underwent substantial thinning of 230 to 265 m. Comparison of sub-surface water temperature anomalies and variations in air...... the projection of future sea level rise, a long-term data record that reveals the mass balance beyond such episodic events is required. Here, we extend the observational record of marginal thinning of Helheim and Kangerdlugssuaq glaciers from 10 to more than 80 years. We show that, although the frontal portion...

  13. Spatial-temporal variation of glacier over koshi basin, Himalaya

    Science.gov (United States)

    Gao, Y.; Yang, X.; Yao, T.

    2011-12-01

    Glacial change is a sensitive indicator of climate change and glacier meltwaters are vital water resource for more than 1/6 people in South and Central Asia. Due to the large extent and difficult accessibility of high mountainous terrain, there are few ground-based glacial observations. In the last decade, multi-temporal satellite imagery and older aerial photography have been used extensively to quantify glacier parameters such as glacier area, length, elevation, hypsography, and ice volume in mountainous areas throughout the world. In this study, a glacier inventory for Koshi Basin was generated for the year 1976, 1992, 2000 and 2009 using automated interpretation with remote sensing, GIS techniques and manual adjustments based on topographic maps, Landsat TM/ETM+, and SRTM DEM data. The area change of about ~3,407km2 was identified. During the past two decades, the average retreat rate of these glaciers was ~5.8% while the retreat rate from 2000 to 2009 was ~14.23%. Moreover, heavily debris-covered glaciers exist in this region. Some of them even extend several kilometers upstream from their terminus such as Kong Bu Re Bu Sang glacier. From 1992 to 2000, the decrease in total glacier area is ~30km2 while the debris coverage increased ~20km2. These increases generally occur near the boundary between clean ice and debris-covered glacier, while the glacial fronts are remarkably stable. In order to identify the effect of debris-covered glaciers, the variations of glacier area, length and elevation were calculated with and without debris-covered glaciers, respectively. Results show although the terminuses of glacial front were stagnant, the increase in debris-covered glacier contributes to the clean ice's length decrease and elevation increase, and thereby affects glacier's response to climate change. So we suggest that in the area where debris-covered glaciers are common, the clean ice and debris-covered area should be separated and the debris-covered part should

  14. On the magnitude and frequency of Karakoram Glacier surges

    Directory of Open Access Journals (Sweden)

    D. J. Quincey

    2013-10-01

    Full Text Available The return periods of Karakoram glacier surges are almost entirely unknown. Here, we present evidence of an historic surge of the Khurdopin Glacier that began in the mid-1970s and peaked in 1979. Measured surface displacements reached > 5 km yr–1, two orders of magnitude faster than during quiescence and twice as large as any previously recorded velocity in the region. The Khurdopin Glacier next surged in the late-1990s, equating to a return period of 20 yr. Surge activity in the region needs to be better understood if accurate mass balance assessments of Hindu-Kush–Karakoram–Himalaya glaciers are to be made.

  15. 纳木错流域近30年来湖泊-冰川变化对气候的响应%The response of lake-glacier variations to climate change in Nam Co Catchment, central Tibetan Plateau, during 1970-2000

    Institute of Scientific and Technical Information of China (English)

    吴艳红; 朱立平

    2008-01-01

    Based upon the 1970 aero-photo topographic map, and TM/ETM satellite images taken in 1991 and 2000, the authors artificially interpreted boundaries of lake and glaciers in Nam Co Catchment, and quantified lake-glacier area variations in different stages by "inte-grated method" with the support of GIS. Results show that from 1970 to 2000, lake area in-creased from 1942.34 km2 to 1979.79 km2 at a rate of 1.27 km2/a, while glacier area de-creased from 167.62 km2 to 141.88 km2 at a rate of 0.86 km2/a. The increasing rate of lake in 1991-2000 was 1.76 km2/a that was faster than 1.03 km2/a in 1970-1991, while in the same period of time, the shrinking rates of glaciers were 0.97 km2/a and 0.80 km2/a respectively.Important factors, relevant to lake and glacier response to the climate, such as air tempera-ture, precipitation, potential evapotranspiration and their values in warm and cold seasons,were discussed. The result suggests that temperature increasing is the main reason for the accelerated melting of glaciers. Lake expansion is mainly induced by the increase of the gla-cier melting water, increase of precipitation and obvious decrease of potential evapotranspi-ration. Precipitation, evaporation and their linkages with lake enlargement on regional scale need to be thoroughly studied under the background of global warming and glacier retreating.

  16. Representing moisture fluxes and phase changes in glacier debris cover using a reservoir approach

    Science.gov (United States)

    Collier, E.; Nicholson, L. I.; Brock, B. W.; Maussion, F.; Essery, R.; Bush, A. B. G.

    2014-08-01

    Due to the complexity of treating moisture in supraglacial debris, surface energy balance models to date have neglected moisture infiltration and phase changes in the debris layer. The latent heat flux (QL) is also often excluded due to the uncertainty in determining the surface vapour pressure. To quantify the importance of moisture on the surface energy and climatic mass balance (CMB) of debris-covered glaciers, we developed a simple reservoir parameterization for the debris ice and water content, as well as an estimation of the latent heat flux. The parameterization was incorporated into a CMB model adapted for debris-covered glaciers. We present the results of two point simulations, using both our new "moist" and the conventional "dry" approaches, on the Miage Glacier, Italy, during summer 2008 and fall 2011. The former year coincides with available in situ glaciological and meteorological measurements, including the first eddy-covariance measurements of the turbulent fluxes over supraglacial debris, while the latter contains two refreeze events that permit evaluation of the influence of phase changes. The simulations demonstrate a clear influence of moisture on the glacier energy and mass-balance dynamics. When water and ice are considered, heat transmission to the underlying glacier ice is lower, as the effective thermal diffusivity of the saturated debris layers is reduced by increases in both the density and the specific heat capacity of the layers. In combination with surface heat extraction by QL, subdebris ice melt is reduced by 3.1% in 2008 and by 7.0% in 2011 when moisture effects are included. However, the influence of the parameterization on the total accumulated mass balance varies seasonally. In summer 2008, mass loss due to surface vapour fluxes more than compensates for the reduction in ice melt, such that the total ablation increases by 4.0%. Conversely, in fall 2011, the modulation of basal debris temperature by debris ice results in a decrease

  17. Earth system consequences of a Pine Island Glacier collapse

    Science.gov (United States)

    Green, Mattias; Schmittner, Andreas

    2016-04-01

    An intermediate complexity climate model is used to simulate the impact of an accelerated Pine Island Glacier mass loss on the large-scale ocean circulation and climate. Simulations are performed for pre-industrial conditions using hosing levels consistent with present day observation of 3,000 m3 s‑1, at an accelerated rate of 6,000 m3 s‑1, and at a total collapse rate of 100,000 m3 s‑1, and in all experiments the hosing lasted 100 years. It is shown that even a modest input of meltwater from the glacier can introduce an initial cooling over the upper part of the Southern Ocean due to increased stratification and ice cover leading to a reduced upward heat flux from Circumpolar Deep Water. This causes global ocean heat content to increase and global surface air temperatures to decrease. The Atlantic Meridional Overturning Circulation (AMOC) increases, presumably due to changes in the density difference between Antarctic Intermediate Water and North Atlantic Deep Water. Simulations with a simultaneous hosing and increases of atmospheric CO2 concentrations show smaller effects of the hosing on global surface air temperature and ocean heat content, which we attribute to the melting of Southern Ocean sea ice. The sensitivity of the AMOC to the hosing is also reduced as the warming by the atmosphere completely dominates the perturbations. Further consequences for oceanic biogeochemical cycles in realistic future warming scenarios are discussed.

  18. Quality controlled glacier inventory in high Asian mountains

    Science.gov (United States)

    Sakai, A.; Nuimura, T.; Taniguchi, K.; Lamsal, D.; Nagai, H.; Tsutaki, S.; Kozawa, A.; Hoshina, Y.; Takenaka, S.; Omiya, S.; Tsunematsu, K.; Tshering, P.; Fujita, K.; Okamoto, S.

    2013-12-01

    Glacier inventories provide a basic information for the water resources, glacier mass balance and ice volume at continental areas. Although glaciers in the Asian mountain are thought to play an important role for the regional water resources (Immerzeel et al., 2010), glacier distribution in the Asia have been poorly understood. Our GAMDAM (Glacier Area Mapping for Discharge in Asian Mountains) project have conducted to establish a glacier inventory with the aim of estimating glacier runoff contribution to river runoff. Our target region covers the High Mountain Asia, extending from 27 to 52 degrees N and from 68 to 104 degrees E. Glacier outlines were manually delineated using more than 260 of LANDSAT images taken from 1999 to 2003. Thermal infrared band was also used to delineate termini of debris-covered glaciers with help of high resolution images on Google Earth. The manual delineation has been conducted for more than two years by 5-7 operators. We conducted several tests, along which the operators delineated the same regions, and assessed the quality and criteria, and fed them back to the operators. At the end of June 2013, the inventory was completed 80% with about 63000 glaciers covering 7.8 × 10^4 km^2. Median elevation of glaciers has been interpreted as a proxy for the equilibrium line altitude (ELA), at which the accumulation and ablation were equal and thus the mass balance was zero (Braithwaite and Raper, 2009). Distribution of the median altitude derived from the GAMDAM glacier inventory was well consistent with that previously reported (Shi et al., 1980).

  19. Reconstructing the glacier contribution to sea-level rise back to 1850

    NARCIS (Netherlands)

    Oerlemans, J.; Dyurgerov, M.; van de Wal, R.S.W.

    2007-01-01

    We present a method to estimate the glacier contribution to sea-level rise from glacier length records. These records form the only direct evidence of glacier changes prior to 1946, when the first systematic mass-balance observations began. A globally rep- resentative length signal is calculated fro

  20. Differences in dissolved organic matter lability between alpine glaciers and alpine rock glaciers of the American West

    Science.gov (United States)

    Hall, E.; Fegel, T. S., II; Baron, J.; Boot, C. M.

    2015-12-01

    While alpine glaciers in montane regions represent the largest flux of dissolved organic matter (DOM) from global ice melt no research has examined the bioavailability of DOM melted out of glacial ice in the western continental United States. Furthermore, rock glaciers are an order of magnitude more abundant than ice glaciers in U.S., yet are not included in budgets for perennial ice carbon stores. Our research aims to understand differences in the bioavailability of carbon from ice glaciers and rock glaciers along the Central Rocky Mountains of Colorado. Identical microbial communities were fed standardized amounts of DOM from four different ice glacier-rock glaciers pairs. Using laboratory incubations, paired with mass spectrometry based metabolomics and 16S gene sequencing; we were able to examine functional definitions of DOM lability in glacial ice. We hypothesized that even though DOM quantities are similar in the outputs of both glacial types in our study area, ice glacial DOM would be more bioavailable than DOM from rock glaciers due to higher proportions of byproducts from microbial metabolism than rock glacier DOM, which has higher amounts of "recalcitrant" plant material. Our results show that DOM from ice glaciers is more labile than DOM from geologically and geographically similar paired rock glaciers. Ice glacier DOM represents an important pool of labile carbon to headwater ecosystems of the Rocky Mountains. Metabolomic analysis shows numerous compounds from varying metabolite pathways, including byproducts of nitrification before and after incubation, meaning that, similar to large maritime glaciers in Alaska and Europe, subglacial environments in the mountain ranges of the United States are hotspots for biological activity and processing of organic carbon.

  1. Meltwater run-off from Haig Glacier, Canadian Rocky Mountains, 2002–2013

    OpenAIRE

    Marshall, S.J.

    2014-01-01

    Observations of high-elevation meteorological conditions, glacier mass balance, and glacier run-off are sparse in western Canada and the Canadian Rocky Mountains, leading to uncertainty about the importance of glaciers to regional water resources. This needs to be quantified so that the impacts of ongoing glacier recession can be evaluated with respect to alpine ecology, hydroelectric operations, and water resource management. In this manuscript the seasonal evolution of gla...

  2. Meltwater runoff from Haig Glacier, Canadian Rocky Mountains, 2002–2013

    OpenAIRE

    Marshall, S. J.

    2014-01-01

    Observations of high-elevation meteorological conditions, glacier mass balance, and glacier runoff are sparse in western Canada and the Canadian Rocky Mountains, leading to uncertainty about the importance of glaciers to regional water resources. This needs to be quantified so that the impacts of ongoing glacier recession can be evaluated with respect to alpine ecology, hydroelectric operations, and water resource management. I assess the seasonal evolution of ...

  3. Glacier dynamics at Helheim and Kangerdlugssuaq glaciers, southeast Greenland, since the Little Ice Age

    Science.gov (United States)

    Khan, S. A.; Kjeldsen, K. K.; Kjær, K. H.; Bevan, S.; Luckman, A.; Aschwanden, A.; Bjørk, A. A.; Korsgaard, N. J.; Box, J. E.; van den Broeke, M.; van Dam, T. M.; Fitzner, A.

    2014-08-01

    Observations over the past decade show significant ice loss associated with the speed-up of glaciers in southeast Greenland from 2003, followed by a deceleration from 2006. These short-term, episodic, dynamic perturbations have a major impact on the mass balance on the decadal scale. To improve the projection of future sea level rise, a long-term data record that reveals the mass balance beyond such episodic events is required. Here, we extend the observational record of marginal thinning of Helheim and Kangerdlugssuaq glaciers from 10 to more than 80 years. We show that, although the frontal portion of Helheim Glacier thinned by more than 100 m between 2003 and 2006, it thickened by more than 50 m during the previous two decades. In contrast, Kangerdlugssuaq Glacier underwent minor thinning of 40-50 m from 1981 to 1998 and major thinning of more than 100 m after 2003. Extending the record back to the end of the Little Ice Age (prior to 1930) shows no thinning of Helheim Glacier from its maximum extent during the Little Ice Age to 1981, while Kangerdlugssuaq Glacier underwent substantial thinning of 230 to 265 m. Comparison of sub-surface water temperature anomalies and variations in air temperature to records of thickness and velocity change suggest that both glaciers are highly sensitive to short-term atmospheric and ocean forcing, and respond very quickly to small fluctuations. On century timescales, however, multiple external parameters (e.g. outlet glacier shape) may dominate the mass change. These findings suggest that special care must be taken in the projection of future dynamic ice loss.

  4. Chicxulub impact, climate changes and mass-extinctions

    Science.gov (United States)

    Smit, J.

    2010-03-01

    sections mentioned above. At the K/Pg itself, no unambiguous indications for a sealevel change have been documented anywhere, although in the Gulf sometimes a tsunami or gravity flow deposit with Chicxulub ejecta has been mistaken for a transgressive sequence. Therefore, there is no obvious connection between any sealevel change and climate changes around K/PgB. The impact ejecta (Ir, shocked qz) are global and occur exactly at K/PgB. Thus far, only one impact, the Chicxulub impact has been identified. However, the occurrence of multiple impacts remains a distinct possibility, as double craters exist, and a shower of impacts, possibly as result of a breakup event (Baptistina, Bottke, 2007) in the asteroid belt is possible. However, such hypothesis requires extraordinary evidence because of the extremely small probability! Thus far, the evidence for an impact after K/PgB is based on ambiguous evidence in reworked sediments in Beloc, Haiti and Coxquihui, Mexico, but nowhere outside the Gulf of Mexico. Evidence for a Chicxulub impact about 0.3 Ma before another, equally large, impact at K/PgB likewise has been interpreted from disturbed sediments in the Gulf, and is therefore highly suspect (Keller, 2009). Widespread evidence from the double K/PgB ejecta layer in coal-swamp deposits in the US western interior demonstrates that the K/PgB impact and the Chicxulub impact are the same. This leaves the Chicxulub impact as the only agent that can be held responsible for the mass-extinctions. The question is, what environmental or climate changes were induced by the impact, and on what timescales? Pre-impact signals for change (diversity, stable isotope shifts) are influenced by leaching or bioturbation of the uppermost 10 cm of the Cretaceous. He-isotopes do not support a scenario where the Chicxulub impact occurs within a pedestal of cometary debris, the arrival of which could lead to environmental stress. The effects of the Chicxulub impact must have been almost immediate. Even

  5. Modelling the dynamics and boundary processes of Svalbard glaciers

    OpenAIRE

    van Pelt, W. J. J.

    2014-01-01

    The focus of this thesis is on improving our understanding of surface and basal processes in the context of glaciers in Svalbard. At the surface, interactions with the atmosphere and underlying snow determine the surface mass balance. A coupled model is applied to Nordenskiöldbreen, a tidewater glacier in central Svalbard, to quantify the surface mass balance and the significance of refreezing of percolating melt water. It is found that for 1989-2010, the annual mass balance was negative (-0....

  6. Modelled climate sensitivity of the mass balance of Morteratschgletscher and its dependence on albedo parameterization

    NARCIS (Netherlands)

    Klok, E.J.; Oerlemans, J.

    2004-01-01

    This paper presents a study of the climate sensitivity of the mass balance of Morteratschgletscher in Switzerland, estimated from a two-dimensional mass balance model. Since the albedo scheme chosen is often the largest error source in mass balance models, we investigated the impact of using differe

  7. Glacier loss and emerging hydrologic vulnerabilities in the Peruvian Andes

    Science.gov (United States)

    Mark, B. G.; McKenzie, J. M.; Baraer, M.; Lagos, P.; Lautz, L.; Carey, M.; Bury, J.; Crumley, R.; Wigmore, O.; Somers, L. D.

    2015-12-01

    Accelerating glacier recession in the tropical Andes is transforming downstream hydrology, while increasing demands for water by end-users (even beyond the watershed limits) is complicating the assessment of vulnerability. Future scenarios of hydro-climatic vulnerability require a better understanding of coupled hydrologic and human systems, involving both multiscale process studies and more robust models of glacier-climate interactions. We synthesize research in two proglacial valleys of glacierized mountain ranges in different regions of Peru that are both in proximity to growing water usage from urban sectors, agriculture, hydroelectric generation, and mining. In both the Santa River watershed draining the Cordillera Blanca and the Shullcas River watershed below Hyuatapallana Mountain in Junin, glaciers have receded over 25% since the 1980s. Historical runoff and glacier data, combined with glacier-climate modeling, show a long-term decrease in discharge resulting from a net loss of stored water. We find evidence that this altered hydrology is transforming proglacial wetland ecology and water quality, even while water resource use has intensified. Beyond glaciers, our results show that over 60% of the dry season base flow in each watershed is groundwater sourced from heterogeneous aquifers. Municipal water supply in Huancayo already relies on 18 groundwater wells. Perceptions of water availability and actual water use practices remain relatively divorced from the actual water resources provided from each mountain range. Critical changes in glacier volume and water supply are not perceived or acknowledged consistently amongst different water users, nor reflected in water management decisions. In order to identify, understand, model, and adapt to climate-glacier-water changes, it is vital to integrate the analysis of water availability and groundwater processes (the domain of hydrologists) with that of water use (the focus for social scientists). Attention must be

  8. Growth of a post-Little Ice Age submarine fan, Glacier Bay, Alaska

    Science.gov (United States)

    Carlson, P.R.; Cowan, E.A.; Powell, R.D.; Cai, J.

    1999-01-01

    A small Holocene fan is forming where Queen Inlet, a hanging valley, enters West Arm fjord, Glacier Bay, Alaska. Queen fan formed in the last 80 years following retreat of the Little Ice Age glacier that filled Glacier Bay about 200 yr BP. It was built mainly by a turbidite system originating from Carroll Glacier delta, as the delta formed in the early 1900s at the head of Queen Inlet. The Late Holocene Queen fan is comparable to large Pleistocene fans that formed in the Gulf of Alaska and differs from trough-mouth fans formed by cooler climate glacier systems.

  9. Snow and glaciers in the tropics: the importance of snowfall level and snow line altitude in the Peruvian Cordilleras

    Science.gov (United States)

    Schauwecker, Simone; Rohrer, Mario; Huggel, Christian; Salzmann, Nadine; Montoya, Nilton; Endries, Jason; Perry, Baker

    2016-04-01

    altitude - ranging within only few hundreds of meters within one year - determines the observed high mass balance gradients. An increase in air temperature by for example 1°C during precipitation events may have even stronger impacts on glacier mass balances of tropical glacier than it would have on those of mid-latitude glaciers. This is an important reason for the high sensitivity of tropical glaciers on past and current climatic changes.

  10. Modelling runoff from a Himalayan debris-covered glacier

    Directory of Open Access Journals (Sweden)

    K. Fujita

    2014-02-01

    Full Text Available Although the processes by which glacial debris-mantles alter the melting of glacier ice have been well studied, the mass balance and runoff patterns of Himalayan debris-covered glaciers and the response of these factors to climate change are not well understood. Many previous studies have addressed mechanisms of ice melt under debris mantles by applying multiplicative parameters derived from field experiments, and other studies have calculated the details of heat conduction through the debris layer. However, those approaches cannot be applied at catchment scales because debris distributions are heterogeneous and difficult to measure. Here, we establish a runoff model for a Himalayan debris-covered glacier in which the spatial distribution of the thermal properties of the debris mantle is estimated from remotely sensed multi-temporal data. We validated the model for the Tsho Rolpa Glacial Lake–Trambau Glacier basin in the Nepal Himalaya, using hydro-meteorological observations obtained for a 3.5 yr period (1993–1996. We calculated long-term averages of runoff components for the period 1980–2007 using gridded reanalysis datasets. Our calculations suggest that excess meltwater from the debris-covered area contributes significantly to the total runoff, mainly because of its location at lower elevations. Uncertainties in runoff values due to estimations of the thermal properties and albedo of the debris-covered surface were assessed to be approximately 8% of the runoff from the debris-covered area. We evaluated the sensitivities of runoff components to changes in air temperature and precipitation. As expected, warmer air temperatures increase the total runoff by increasing the melting rate; however, increased precipitation slightly reduces the total runoff, as ice melting is suppressed by the increased snow cover and associated high albedo. The response of total runoff to changing precipitation is complex because of the different responses of

  11. Contemporary processes of environmental information in the atmosphere-glacier-runoff system in an area of typical monsoon temperate glacier

    Institute of Scientific and Technical Information of China (English)

    何元庆; 姚檀栋; 张晓君; 陈拓; 杨梅学; 孙维贞; 李凤霞

    2001-01-01

    Sampling was carried out at Baishui No.1, the largest glacier on Mt. Yulong, China, during the summers of 1999 and 2000, to investigate the spatial variations of oxygen isotopes in the atmosphere-glacier-river system. The results confirm that there is an inverse relation between the oxygen isotopic composition of precipitation and air temperature/precipitation amount. This suggests that a strong "precipitation amount effect" exists in this typical monsoon temperate-glacier region. There are marked differences of the δ18O values of winter-accumulated snow, glacial meltwater, summer precipitation and the glacier-fed river water. Spatial and temporal variations of isotopic composition are controlled by climatic conditions. Isotopic fractionation and differentiation occur during phase changes, snow-to-ice and ice-to-meltwater transformations, and runoff processes. Variations of stable isotopes in glacier runoff can indicate variations of sources of supply, as well as different discharge-related processes. I

  12. Higher surface mass balance of the Greenland ice sheet revealed by high-resolution climate modeling

    OpenAIRE

    Ettema, J.; M. R. van den Broeke; van Meijgaard, E.; Van De Berg, W. J.; Bamber, Jonathan L.; Box, J. E.; Bales, R. C.

    2009-01-01

    High-resolution (∼11 km) regional climate modeling shows total annual precipitation on the Greenland ice sheet for 1958-2007 to be up to 24% and surface mass balance up to 63% higher than previously thought. The largest differences occur in coastal southeast Greenland, where the much higher resolution facilitates capturing snow accumulation peaks that past five-fold coarser resolution regional climate models missed. The surface mass balance trend over the full 1958-2007 period reveals the cla...

  13. Probabilistic estimation of glacier volume and glacier bed topography: the Andean glacier Huayna West

    OpenAIRE

    V. Moya Quiroga; Mano, A.; Asaoka, Y; K. Udo; Kure, S.; Mendoza, J.

    2013-01-01

    Glacier retreat will increase sea level and decrease fresh water availability. Glacier retreat will also induce morphologic and hydrologic changes due to the formation of glacial lakes. Hence, it is important not only to estimate glacier volume, but also to understand the spatial distribution of ice thickness. There are several approaches for estimating glacier volume and glacier thickness. However, it is not possible to select an optimal approach that works for all locations. It is important...

  14. Seasonal dynamic thinning at Helheim Glacier

    DEFF Research Database (Denmark)

    Bevan, Suzanne L.; Luckman, Adrian; Khan, Shfaqat Abbas;

    2015-01-01

    We investigate three annual mass-balance cycles on Helheim Glacier in south-east Greenland using TanDEM-X interferometric digital elevation models (DEMs), bedrock GPS measurements, and ice velocity from feature-tracking. The DEMs exhibit seasonal surface elevation cycles at elevations up to 800 m...

  15. China's Glacier Inventory Completed

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ A 12-volume Chinese Glacier Inventory has recently been finished by a group of Chinese glaciologists headed by Prof. Shi Yafeng from the Cold and Arid Regions Environmental and Engineering Research Institute under CAS.

  16. Melting Himalayan glaciers contaminated by legacy atmospheric depositions are important sources of PCBs and high-molecular-weight PAHs for the Ganges floodplain during dry periods.

    Science.gov (United States)

    Sharma, Brij Mohan; Nizzetto, Luca; Bharat, Girija K; Tayal, Shresth; Melymuk, Lisa; Sáňka, Ondřej; Přibylová, Petra; Audy, Ondřej; Larssen, Thorjørn

    2015-11-01

    Melting glaciers are natural redistributors of legacy airborne pollutants, affecting exposure of pristine proglacial environments. Our data shows that melting Himalayan glaciers can be major contributors of polychlorinated biphenyls (PCBs) and high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) for surface water in the Gangetic Plain during the dry season. Glacial emissions can exceed in some cases inputs from diffuse sources within the catchment. We analyzed air, deposition and river water in several sections along the Ganges River and its major headwaters. The predominant glacial origin of these contaminants in the Himalayan reach was demonstrated using air-water fugacity ratios and mass balance analysis. The proportion of meltwater emissions compared to pollutant discharge at downstream sections in the central part of the Gangetic Plain was between 2 and 200%. By remobilizing legacy pollutants from melting glaciers, climate change can enhance exposure levels over large and already heavily impacted regions of Northern India. PMID:26312740

  17. Biodiversity under threat in glacier-fed river systems

    Science.gov (United States)

    Jacobsen, Dean; Milner, Alexander M.; Brown, Lee E.; Dangles, Olivier

    2012-05-01

    Freshwater biodiversity is under threat across the globe, with climate change being a significant contributor. One impact of climate change is the rapid shrinking of glaciers, resulting in a reduction in glacial meltwater contribution to river flow in many glacierized catchments. These changes potentially affect the biodiversity of specialized glacier-fed river communities. Perhaps surprisingly then, although freshwater biodiversity is a major conservation priority, the effects of shrinkage and disappearance of glaciers on river biodiversity have hitherto been poorly quantified. Here we focus on macroinvertebrates (mainly insect larvae) and demonstrate that local (α) and regional (γ) diversity, as well as turnover among reaches (β-diversity), will be consistently reduced by the shrinkage of glaciers. We show that 11-38% of the regional species pools, including endemics, can be expected to be lost following complete disappearance of glaciers in a catchment, and steady shrinkage is likely to reduce taxon turnover in proglacial river systems and local richness at downstream reaches where glacial cover in the catchment is less than 5-30%. Our analysis demonstrates not only the vulnerability of local biodiversity hotspots but also that extinction will probably greatly exceed the few known endemic species in glacier-fed rivers.

  18. On the role of buoyant flexure in glacier calving

    Science.gov (United States)

    Wagner, Till J. W.; James, Timothy D.; Murray, Tavi; Vella, Dominic

    2016-04-01

    Interactions between glaciers and the ocean are key for understanding the dynamics of the cryosphere in the climate system. Here we investigate the role of hydrostatic forces in glacier calving. We develop a mathematical model to account for the elastic deformation of glaciers in response to three effects: (i) marine and lake-terminating glaciers tend to enter water with a nonzero slope, resulting in upward flexure around the grounding line; (ii) horizontal pressure imbalances at the terminus are known to cause hydrostatic in-plane stresses and downward acting torque; (iii) submerged ice protrusions at the glacier front may induce additional buoyancy forces that can cause calving. Our model provides theoretical estimates of the importance of each effect and suggests geometric and material conditions under which a given glacier will calve from hydrostatic flexure.We find good agreement with observations. This work sheds light on the intricate processes involved in glacier calving and can be hoped to improve our ability to model and predict future changes in the ice-climate system.

  19. Younger Dryas glaciers in the High Atlas, Morocco

    Science.gov (United States)

    Hughes, Philip; Fink, David

    2016-04-01

    Twelve cirque glaciers formed during the Younger Dryas on the mountains of Aksoual (3912 m a.s.l.) and Adrar el Hajj (3129 m a.s.l.) in the Marrakesh High Atlas. Moraines in two separate cirques on these mountains have been dated using 10Be and 36Cl exposure dating. In both cirques the age scatter is relatively small (13.8-10.1 ka) and all ages overlap within error with the Younger Dryas (12.9-11.7 ka). The glaciers were small and covered ELAs) ranging from 2470 and 3560 m. This large range is attributed to local topoclimatic factors with the lowest glacier (confirmed as Younger Dryas in age by 3 exposure ages) occupying a very steep cirque floor where a combination of steep glacier gradient and a large potential avalanche catchment enabled its low-lying position. This indicates that caution should be taken when using single glacier sites for reconstructing regional palaeoclimate, especially those formed in steep catchments that have strong topoclimatic controls. The average ELA of the twelve Younger Dryas glaciers was c. 3109 m a.s.l. (St Dev = 325 m) and this represents an ELA depression of > 1000 m from the modern theoretical regional ELA. Under precipitation values similar to today this would require a mean annual temperature depression of 9°C. Moreover, the glacier-climate modelling indicates that it is very unlikely that climate was drier than today during the Younger Dryas in the Marrakesh High Atlas.

  20. A note on the water budget of temperate glaciers

    Directory of Open Access Journals (Sweden)

    J. Oerlemans

    2013-06-01

    Full Text Available In this note the total dissipative melting in temperate glaciers is studied. The analysis is based on the notion that the dissipation is determined by the loss of potential energy, due to the downward motion of mass (ice, snow, meltwater and rain. A mathematical formulation of the dissipation is developed and applied to a simple glacier geometry. In a next step, meltwater production resulting from enhanced ice motion during a glacier surge is calculated. The amount of melt energy available follows directly from the lowering of the centre of gravity of the glacier. To illustrate the concept, schematic calculations are presented for a number of glaciers with different geometric characteristics. Typical dissipative melt rates, expressed as water-layer depth averaged over the glacier, range from a few cm per year for smaller glaciers to half a meter per year for Franz-Josef Glacier, one of the most active glaciers in the world (in terms of mass turnover. The total generation of meltwater during a surge is typically half a meter. For Variegated Glacier a value of 70 cm is found, for Kongsvegen 20 cm. These values refer to water layer depth averaged over the entire glacier. The melt rate depends on the duration of the surge. It is generally an order of magnitude larger than the water production by "normal" dissipation. On the other hand, the additional basal melt rate during a surge is comparable in magnitude to the water input from meltwater and precipitation. This suggests that enhanced melting during a surge does not grossly change the total water budget of a glacier. Basal water generated by enhanced sliding is an important ingredient of many theories of glacier surges. It provides a positive feedback mechanism that actually makes the surge happen. The results found here suggest that this can only work if water generated by enhanced sliding is accumulating in a part of the glacier base where surface meltwater and rain has no or very limited access

  1. Variability of the "glaciological regime" and its consequences for interpretation and modelling of glacier length changes - a case study from maritime South Norway

    Science.gov (United States)

    Winkler, S.; Nesje, A.

    2009-04-01

    Mountain glaciers are acknowledged as high-resolution indicators of short-, medium-, and long-term climate changes. Variations in glacier mass, area, length, and frontal position have important effects upon various aspects of sustainable development in mountain regions. Maritime mountain glaciers can react very sensitive to changes of the ‘glaciological regime', i.e. the relationship between mass-balance or length changes and predominant weather or climate conditions. The steep sensitive-reacting outlet glaciers of Jostedalsbreen, western South Norway, underwent two fairly contrasting periods during the past 20 years. Interpretation of this ‘extreme' behaviour deserved special attention. A considerable increase in ice mass and related frontal advance during the AD 1990s was caused by increased winter precipitation. Relative contributions of the winter balance to the annual net balance variations were high during the last decades of the 20th century AD. By contrast, glacier tongues experiences a sharp retreat in the most recent years since c. AD 2000. Above-average summer air temperatures unambiguously caused the most recent retreat. This retreat was, however, not clearly linked to mass-balance data as its proportion significantly exceeded the slight contemporary mass loss. The virtual absence of any time lag of frontal response indicates a regime change towards a ‘disturbed' dynamic response of the glacier tongue occurring around c. AD 2000. Detailed analysis of mass-balance, length variation, and climate data from maritime Southern Norway reveals their variations are not entirely determined by air temperature changes, as implicated by most existing models. Substantial changes occurred after AD 2000 with the correlation of different mass-balance parameters to length variations. The correlation of net balance to length variation dropped significant during to the most recent retreat. Comparable changes between long-term means and the most recent retreat phase

  2. Multi-temporal study of BELVEDERE glacier for hydrologic hazard monitoring and water resource estimation using UAV: tests and first results

    Science.gov (United States)

    Piras, Marco; Cina, Alberto; De Michele, Carlo; Pinto, Livio; Barzaghi, Riccardo; Maschio, Paolo F.; Avanzi, Francesco; Bianchi, Alberto; Deidda, Cristina; Donizetti, Alberto; Giani, Giulia; Giarrizzo, Giuseppe; Negrini, Alessandro; Rampazzo, Alessandro; Savaia, Gianluca; Soria, Enrica

    2016-04-01

    Nowadays, expected effects of climate change at local, regional and global scales endanger hydrologic budgets of Alpine regions. An example is the massive shrinkage of mountain glaciers, with the consequent problem of water resources reduction for civil population and ecosystems. Therefore, it is very important to monitor glaciers' evolution, in order to allow an estimation of glaciers' reduction and possible effects on the hydrologic cycle. In 2015, a research team called DREAM (Drone Technology for Water Resources and hydrologic hazards Monitoring) has been created within the framework of "Alta Scuola Politecnica", joint initiative between Politecnico di Milano and Politecnico di Torino (Italy), and composed by 15 people among students, research associates and professors belonging to the two universities. The goal of the research team is to investigate new technologies and tools, including Unmanned Aerial Vehicle (UAVs), for monitoring natural hazard and evaluating water resources at different scales. In particular, in this first step, the DREAM team has selected as test site the eastern slopes of Monte Rosa and its long glacier tongue (Belvedere glacier). This area of Monte Rosa massif has an altitude range between 2000 m up to 4500 m ASL, while the glacier tongue has an extension greater than 3 km 2. Usually, glacier thickness and area evolution are monitored using, e.g., time-consuming field activities based on point stratigraphy and mass balances, or radar sounding, which do not allow to obtain a continuous-time, detailed and accurate information about surface and volume evolution at fine spatial resolutions. In this framework, we have used a fixed-wing UAV (eBee sensesly) to acquire RGB images, in order to generate a dense DSM (DDSM) and an orthophoto of the glacier, with a high resolution (4-6 cm). In this way, we aim at analyzing the variations of glacier volume in time. The acquisition was carried out with two different campaigns of measurement in October

  3. Effects of local microclimates on the surface sensible heat flux on a mid-latitude alpine valley glacier using Large-Eddy Simulations

    Science.gov (United States)

    Sauter, Tobias; Galos, Stephan

    2016-04-01

    While the large-scale climate conditions play an important role in shaping the environment in which glaciers exist, the mass and energy balance of each individual glacier are dictated by local conditions. Given the complex mountain topography around alpine glaciers, it is not trivial to find a direct link between the large-scale atmospheric motions and the local-scale weather conditions at an individual glacier. Non-local dynamic effects due to the surrounding complex topography can significantly modify the spatial variability of exchange processes, either by small scale circulations or episodic entrainment of heat and momentum by burst events. Motivated by the fact that distributed glacier models strongly rely on the quality of high resolution forcing data to adequately represent the glacier wide ablation and accumulation processes, the present study investigates (i) whether non-local topographic effects have a significant impact on the spatial distribution of turbulent sensible heat fluxes (local microclimates) over alpine glaciers, and (ii) how much variability is smoothed out when using linearly interpolated fields together with the commonly used bulk approach. To answer these questions, we perform highly resolved and properly designed case experiments by Large-Eddy Simulations with real topography to determine the impact of topographic flow features on the spatial variability of the surface sensible heat flux and compare the fields with those derived with the bulk approach. The analysis shows that there is a significant spatial variability of the mean fluxes with values ranging from -10 Wm-2 to -120 Wm-2. Since the sensible heat flux can make up to 40% of the total melting on mid-latitude alpine valley glaciers, the heterogeneity of the fluxes can substantially dictate the local melting rates. When estimating the glacier-wide surface heat fluxes on the basis of point-measurements and the bulk approach, a considerable amount of spatial information is lost. All

  4. Climate Reconstructions of the Younger Dryas: An ELA Model Investigating Variability in ELA Depressions, Temperature, and Precipitation Changes for the Graubϋnden Alps

    Science.gov (United States)

    Keeler, D. G.; Rupper, S.; Schaefer, J. M.; Finkel, R. C.

    2015-12-01

    The high sensitivity of mountain glaciers to even small perturbations in climate, combined with a near global distribution, make alpine glaciers an important target for terrestrial paleoclimate reconstructions. The geomorphic remnant of past glaciers can yield important insights into past climate, particularly in regions where other methods of reconstruction are not possible. The quantitative conversion of these changes in geomorphology to a climate signal, however, presents a significant challenge. A particular need exists for a versatile climate reconstruction method applicable to diverse glacierized regions around the globe. Because the glacier equilibrium line altitude (ELA) provides a more explicit comparison of climate than properties such as glacier length or area, ELA methods lend themselves well to such a need, and allow for a more direct investigation of the primary drivers of mountain glaciations during specific events. Here, we present an ELA model for quantifying changes in climate based on changes in glacier extent, while accounting for differences in glacier width, glacier shape, bed topography, ice thickness, and glacier length. The model furthermore provides bounds on the ΔELA using Monte Carlo simulations. These methods are validated using published mass balances and ELA measurements from 4 modern glaciers in the European Alps. We then use this ELA model, combined with a surface mass and energy balance model, to estimate the changes in temperature/precipitation between the Younger Dryas (constrained by 10Be surface exposure ages) and the present day for three glacier systems in the Graubϋnden Alps. Our results indicate an ELA depression in this area of 257 m ±45 m during the Younger Dryas (YD) relative to today. This corresponds to a 1.3 °C ±0.36 °C decrease in temperature or a 156% ±30% increase in precipitation relative to today. These results indicate the likelihood of a predominantly temperature-driven change rather than a strong

  5. Assessing the links between Greenland Ice Sheet Surface Mass Balance and Arctic climate using Climate Models and Observations

    Science.gov (United States)

    Mottram, Ruth; Rodehacke, Christian; Boberg, Fredrik; Langen, Peter; Sloth Madsen, Marianne; Høyer Svendsen, Synne; Yang, Shuting; Hesselbjerg Christensen, Jens; Olesen, Martin

    2016-04-01

    Changes in different parts of the Arctic cryosphere may have knock-on effects on other parts of the system. The fully coupled climate model EC-Earth, which includes the ice sheet model PISM, is a useful tool to examine interactions between sea ice, ice sheet, ocean and atmosphere. Here we present results from EC-Earth experimental simulations that show including an interactive ice sheet model changes ocean circulation, sea ice extent and regional climate with, for example, a dampening of the expected increase in Arctic temperatures under the RCP scenarios when compared with uncoupled experiments. However, the relatively coarse resolution of the climate model likely influences the calculated surface mass balance forcing applied to the ice sheet model and it is important therefore to evaluate the model performance over the ice sheet. Here, we assess the quality of the climate forcing from the GCM to the ice sheet model by comparing the energy balance and surface mass balance (SMB) output from EC-Earth with that from a regional climate model (RCM) run at very high resolution (0.05 degrees) over Greenland. The RCM, HIRHAM5, has been evaluated over a wide range of climate parameters for Greenland which allows us to be confident it gives a representative climate forcing for the Greenland ice sheet. To evaluate the internal variability in the climate forcing, we compare simulations from HIRHAM5 forced with both the EC-Earth historical emissions and the ERA-Interim reanalysis on the boundaries. The EC-Earth-PISM RCP8.5 scenario is also compared with an EC-Earth run without an ice sheet to assess the impact of an interactive ice sheet on likely future changes. To account for the resolution difference between the models we downscale both EC-Earth and HIRHAM5 simulations with a simple offline energy balance model (EBM).

  6. Ice Volume Changes and Their Characteristics for Representative Glacier against the Background of Climatic Warming --A Case Study of Urumqi Glacier No. 1, Tianshan, China%气候变暖背景下典型冰川储量变化及其特征——以天山乌鲁木齐河源1号冰川为例

    Institute of Scientific and Technical Information of China (English)

    王璞玉; 李忠勤; 李慧林

    2011-01-01

    冰储量变化与冰川水资源变化及其对河川径流的贡献有密切关系。论文以天山乌鲁木齐河源1号冰川为例,基于雷达测厚、冰川测图等多年实测资料,通过GIS技术,计算出该冰川不同时期的储量值,并对其变化特征进行分析。结果表明,乌鲁木齐河源1号冰川1962、1981、1986、2001和2006年的储量分别为10 736.7×104、10 296.2×104、9 989.4×104m3、8 797.9×104和8 115.0×104m3。1962—2006年44 a间,在气候变暖背景下,冰储量亏损24.4%,厚度减薄12%The changes of ice volume are closely related to the changes of glacial water resources and the contribution of melt water to the river runoff.Based on the ice thickness measured data,topographic maps and the long-term field observation data,this study has calculated the ice volume of Urumqi Glacier No.1 in different periods using GIS technique and analyzed the characteristics of their changes.Results indicated that the ice volume of Urumqi Glacier No.1 is 10736.7×104 m3,10296.2×104 m3,9989.4×104 m3,8797.9×104 m3 and 8115.0×104 m3 in 1962,1981,1986,2001 and 2006,respectively.During 1962-2006,the total ice volume of the glacier has reduced by 24.4% and the reduction rate of ice thickness,area and maximum length is 12.1%,14.0% and 7.6%,respectively.The glacier was in a state of rapid shrinking with an accelerated tendency against the background of climatic warming in the past several decades.Before 1981,area shrinkage and terminus retreat was the key cause of the ice volume reduction;during 1981-2001,the reduction of ice volume was caused by three aspects: ice thickness,area and length,and area shrinkage was considered as the main factor;the noticeable reduction in ice volume is due to the intensive thinning of the ice thickness after 2001.

  7. Geographic Names of Iceland's Glaciers: Historic and Modern

    Science.gov (United States)

    Sigurdsson, Oddur; Williams, Richard S.

    2008-01-01

    Climatic changes and resulting glacier fluctuations alter landscapes. In the past, such changes were noted by local residents who often documented them in historic annals; eventually, glacier variations were recorded on maps and scientific reports. In Iceland, 10 glacier place-names are to be found in Icelandic sagas, and one of Iceland's ice caps, Snaefellsjokull, appeared on maps of Iceland published in the 16th century. In the late 17th century, the first description of eight of Iceland's glaciers was written. Therefore, Iceland distinguishes itself in having a more than 300-year history of observations by Icelanders on its glaciers. A long-term collaboration between Oddur Sigurdsson and Richard S. Williams, Jr., led to the authorship of three books on the glaciers of Iceland. Much effort has been devoted to documenting historical glacier research and related nomenclature and to physical descriptions of Icelandic glaciers by Icelanders and other scientists from as far back as the Saga Age to recent (2008) times. The first book, Icelandic Ice Mountains, was published by the Icelandic Literary Society in 2004 in cooperation with the Icelandic Glaciological Society and the International Glaciological Society. Icelandic Ice Mountains was a glacier treatise written by Sveinn Palsson in 1795 and is the first English translation of this important scientific document. Icelandic Ice Mountains includes a Preface, including a summary of the history and facsimiles of page(s) from the original manuscript, a handwritten copy, and an 1815 manuscript (without maps and drawings) by Sveinn Palsson on the same subject which he wrote for Rev. Ebenezer Henderson; an Editor's Introduction; 82 figures, including facsimiles of Sveinn Palsson's original maps and perspective drawings, maps, and photographs to illustrate the text; a comprehensive Index of Geographic Place-Names and Other Names in the treatise; References, and 415 Endnotes. Professional Paper 1746 (this book) is the second

  8. Remotely-Sensed Glacier Change Estimation: a Case Study at Lindblad Cove, Antarctic Peninsula

    Science.gov (United States)

    Fieber, K. D.; Mills, J. P.; Miller, P. E.; Fox, A. J.

    2016-06-01

    This study builds on existing literature of glacier change estimation in polar regions and is a continuation of efforts aimed at unlocking the information encapsulated in archival aerial photography of Antarctic Peninsula glaciers. Historical aerial imagery acquired in 1957 over three marine-terminating glaciers at Lindblad Cove on the West Coast of Trinity Peninsula is processed to extract digital elevation models (DEMs) which are subsequently compared to DEMs generated from present day (2014) WorldView-2 satellite stereo-imagery. The new WorldView-2 images offer unprecedented sub-metre resolution of the Antarctic Peninsula and are explored here to facilitate improved registration and higher accuracy analysis of glacier changes. Unlike many studies, which focus on glacier fronts or only restricted regions of glaciers, this paper presents a complete coverage of elevation changes across the glacier surfaces for two of the studied glaciers. The study utilises a robust least squares matching technique to ensure precise registration of the archival and modern DEMs, which is applied due to lack of existing ground control in this remote region. This case study reveals that, while many glaciers in polar regions are reported as experiencing significant mass loss, some glaciers are stable or even demonstrate mass gain. All three glaciers reported here demonstrated overall mean increases in surface elevation, indicative of positive mass balance ranging from 0.6 to 5.8 metre water equivalent between 1957 and 2014.

  9. REMOTELY-SENSED GLACIER CHANGE ESTIMATION: A CASE STUDY AT LINDBLAD COVE, ANTARCTIC PENINSULA

    Directory of Open Access Journals (Sweden)

    K. D. Fieber

    2016-06-01

    Full Text Available This study builds on existing literature of glacier change estimation in polar regions and is a continuation of efforts aimed at unlocking the information encapsulated in archival aerial photography of Antarctic Peninsula glaciers. Historical aerial imagery acquired in 1957 over three marine-terminating glaciers at Lindblad Cove on the West Coast of Trinity Peninsula is processed to extract digital elevation models (DEMs which are subsequently compared to DEMs generated from present day (2014 WorldView-2 satellite stereo-imagery. The new WorldView-2 images offer unprecedented sub-metre resolution of the Antarctic Peninsula and are explored here to facilitate improved registration and higher accuracy analysis of glacier changes. Unlike many studies, which focus on glacier fronts or only restricted regions of glaciers, this paper presents a complete coverage of elevation changes across the glacier surfaces for two of the studied glaciers. The study utilises a robust least squares matching technique to ensure precise registration of the archival and modern DEMs, which is applied due to lack of existing ground control in this remote region. This case study reveals that, while many glaciers in polar regions are reported as experiencing significant mass loss, some glaciers are stable or even demonstrate mass gain. All three glaciers reported here demonstrated overall mean increases in surface elevation, indicative of positive mass balance ranging from 0.6 to 5.8 metre water equivalent between 1957 and 2014.

  10. ASTER Imaging and Analysis of Glacier Hazards

    Science.gov (United States)

    Kargel, Jeffrey; Furfaro, Roberto; Kaser, Georg; Leonard, Gregory; Fink, Wolfgang; Huggel, Christian; Kääb, Andreas; Raup, Bruce; Reynolds, John; Wolfe, David; Zapata, Marco

    Most scientific attention to glaciers, including ASTER and other satellite-derived applications in glacier science, pertains to their roles in the following seven functions: (1) as signposts of climate change (Kaser et al. 1990; Williams and Ferrigno 1999, 2002; Williams et al. 2008; Kargel et al. 2005; Oerlemans 2005), (2) as natural reservoirs of fresh water (Yamada and Motoyama 1988; Yang and Hu 1992; Shiyin et al. 2003; Juen et al. 2007), (3) as contributors to sea-level change (Arendt et al. 2002), (4) as sources of hydropower (Reynolds 1993); much work also relates to the basic science of glaciology, especially (5) the physical phenomeno­logy of glacier flow processes and glacier change (DeAngelis and Skvarca 2003; Berthier et al. 2007; Rivera et al. 2007), (6) glacial geomorphology (Bishop et al. 1999, 2003), and (7) the technology required to acquire and analyze satellite images of glaciers (Bishop et al. 1999, 2000, 2003, 2004; Quincey et al. 2005, 2007; Raup et al. 2000, 2006ab; Khalsa et al. 2004; Paul et al. 2004a, b). These seven functions define the important areas of glaciological science and technology, yet a more pressing issue in parts of the world is the direct danger to people and infrastructure posed by some glaciers (Trask 2005; Morales 1969; Lliboutry et al. 1977; Evans and Clague 1988; Xu and Feng 1989; Reynolds 1993, 1998, 1999; Yamada and Sharma 1993; Hastenrath and Ames 1995; Mool 1995; Ames 1998; Chikita et al. 1999; Williams and Ferrigno 1999; Richardson and Reynolds 2000a, b; Zapata 2002; Huggel et al. 2002, 2004; Xiangsong 1992; Kääb et al. 2003, 2005, 2005c; Salzmann et al. 2004; Noetzli et al. 2006).

  11. Preliminary Estimation of Black Carbon Deposition from Nepal Climate Observatory-Pyramid Data and Its Possible Impact on Snow Albedo Changes Over Himalayan Glaciers During the Pre-Monsoon Season

    Science.gov (United States)

    Yasunari, T. J.; Bonasoni, P.; Laj, P.; Fujita, K.; Vuillermoz, E.; Marinoni, A.; Cristofanelli, P.; Duchi, R.; Tartari, G.; Lau, K.-M.

    2010-01-01

    The possible minimal range of reduction in snow surface albedo due to dry deposition of black carbon (BC) in the pre-monsoon period (March-May) was estimated as a lower bound together with the estimation of its accuracy, based on atmospheric observations at th