WorldWideScience

Sample records for abrupt climate change

  1. Abrupt change in climate and climate models

    Directory of Open Access Journals (Sweden)

    A. J. Pitman

    2006-01-01

    Full Text Available First, we review the evidence that abrupt climate changes have occurred in the past and then demonstrate that climate models have developing capacity to simulate many of these changes. In particular, the processes by which changes in the ocean circulation drive abrupt changes appear to be captured by climate models to a degree that is encouraging. The evidence that past changes in the ocean have driven abrupt change in terrestrial systems is also convincing, but these processes are only just beginning to be included in climate models. Second, we explore the likelihood that climate models can capture those abrupt changes in climate that may occur in the future due to the enhanced greenhouse effect. We note that existing evidence indicates that a major collapse of the thermohaline circulation seems unlikely in the 21st century, although very recent evidence suggests that a weakening may already be underway. We have confidence that current climate models can capture a weakening, but a collapse in the 21st century of the thermohaline circulation is not projected by climate models. Worrying evidence of instability in terrestrial carbon, from observations and modelling studies, is beginning to accumulate. Current climate models used by the Intergovernmental Panel on Climate Change for the 4th Assessment Report do not include these terrestrial carbon processes. We therefore can not make statements with any confidence regarding these changes. At present, the scale of the terrestrial carbon feedback is believed to be small enough that it does not significantly affect projections of warming during the first half of the 21st century. However, the uncertainties in how biological systems will respond to warming are sufficiently large to undermine confidence in this belief and point us to areas requiring significant additional work.

  2. Abrupt change in climate and climate models

    Directory of Open Access Journals (Sweden)

    A. J. Pitman

    2006-07-01

    Full Text Available First, we review the evidence that abrupt climate changes have occurred in the past and then demonstrate that climate models have developing capacity to simulate many of these changes. In particular, the processes by which changes in the ocean circulation drive abrupt changes appear to be captured by climate models to a degree that is encouraging. The evidence that past changes in the ocean have driven abrupt change in terrestrial systems is also convincing, but these processes are only just beginning to be included in climate models. Second, we explore the likelihood that climate models can capture those abrupt changes in climate that may occur in the future due to the enhanced greenhouse effect. We note that existing evidence indicates that a major collapse of the thermohaline circulate seems unlikely in the 21st century, although very recent evidence suggests that a weakening may already be underway. We have confidence that current climate models can capture a weakening, but a collapse of the thermohaline circulation in the 21st century is not projected by climate models. Worrying evidence of instability in terrestrial carbon, from observations and modelling studies, is beginning to accumulate. Current climate models used by the Intergovernmental Panel on Climate Change for the 4th Assessment Report do not include these terrestrial carbon processes. We therefore can not make statements with any confidence regarding these changes. At present, the scale of the terrestrial carbon feedback is believed to be small enough that it does not significantly affect projections of warming during the first half of the 21st century. However, the uncertainties in how biological systems will respond to warming are sufficiently large to undermine confidence in this belief and point us to areas requiring significant additional work.

  3. Abrupt climate change:Debate or action

    Institute of Scientific and Technical Information of China (English)

    CHENG Hai

    2004-01-01

    Global abrupt climate changes have been documented by various climate records, including ice cores,ocean sediment cores, lake sediment cores, cave deposits,loess deposits and pollen records. The climate system prefers to be in one of two stable states, i.e. interstadial or stadial conditions, but not in between. The transition between two states has an abrupt character. Abrupt climate changes are,in general, synchronous in the northern hemisphere and tropical regions. The timescale for abrupt climate changes can be as short as a decade. As the impacts may be potentially serious, we need to take actions such as reducing CO2emissions to the atmosphere.

  4. Abrupt climate change: can society cope?

    Science.gov (United States)

    Hulme, Mike

    2003-09-15

    Consideration of abrupt climate change has generally been incorporated neither in analyses of climate-change impacts nor in the design of climate adaptation strategies. Yet the possibility of abrupt climate change triggered by human perturbation of the climate system is used to support the position of both those who urge stronger and earlier mitigative action than is currently being contemplated and those who argue that the unknowns in the Earth system are too large to justify such early action. This paper explores the question of abrupt climate change in terms of its potential implications for society, focusing on the UK and northwest Europe in particular. The nature of abrupt climate change and the different ways in which it has been defined and perceived are examined. Using the example of the collapse of the thermohaline circulation (THC), the suggested implications for society of abrupt climate change are reviewed; previous work has been largely speculative and has generally considered the implications only from economic and ecological perspectives. Some observations about the implications from a more social and behavioural science perspective are made. If abrupt climate change simply implies changes in the occurrence or intensity of extreme weather events, or an accelerated unidirectional change in climate, the design of adaptation to climate change can proceed within the existing paradigm, with appropriate adjustments. Limits to adaptation in some sectors or regions may be reached, and the costs of appropriate adaptive behaviour may be large, but strategy can develop on the basis of a predicted long-term unidirectional change in climate. It would be more challenging, however, if abrupt climate change implied a directional change in climate, as, for example, may well occur in northwest Europe following a collapse of the THC. There are two fundamental problems for society associated with such an outcome: first, the future changes in climate currently being

  5. Abrupt climate change and extinction events

    Science.gov (United States)

    Crowley, Thomas J.

    1988-01-01

    There is a growing body of theoretical and empirical support for the concept of instabilities in the climate system, and indications that abrupt climate change may in some cases contribute to abrupt extinctions. Theoretical indications of instabilities can be found in a broad spectrum of climate models (energy balance models, a thermohaline model of deep-water circulation, atmospheric general circulation models, and coupled ocean-atmosphere models). Abrupt transitions can be of several types and affect the environment in different ways. There is increasing evidence for abrupt climate change in the geologic record and involves both interglacial-glacial scale transitions and the longer-term evolution of climate over the last 100 million years. Records from the Cenozoic clearly show that the long-term trend is characterized by numerous abrupt steps where the system appears to be rapidly moving to a new equilibrium state. The long-term trend probably is due to changes associated with plate tectonic processes, but the abrupt steps most likely reflect instabilities in the climate system as the slowly changing boundary conditions caused the climate to reach some threshold critical point. A more detailed analysis of abrupt steps comes from high-resolution studies of glacial-interglacial fluctuations in the Pleistocene. Comparison of climate transitions with the extinction record indicates that many climate and biotic transitions coincide. The Cretaceous-Tertiary extinction is not a candidate for an extinction event due to instabilities in the climate system. It is quite possible that more detailed comparisons and analysis will indicate some flaws in the climate instability-extinction hypothesis, but at present it appears to be a viable candidate as an alternate mechanism for causing abrupt environmental changes and extinctions.

  6. Abrupt climate change: Mechanisms, patterns, and impacts

    Science.gov (United States)

    Schultz, Colin

    2012-08-01

    In the span of only a few decades, the global temperature can soar by more than a dozen degrees Celsius, a feat that 20 years ago was considered improbable, if not impossible. But recent research in the nascent field of rapid climate change has upended the dominant views of decades past. Focusing primarily on events during and after the most recent glaciation, from 80,000 years ago, the AGU monograph Abrupt Climate Change: Mechanisms, Patterns, and Impacts, edited by Harunur Rashid, Leonid Polyak, and Ellen Mosley-Thompson, explores the transient climate transitions that were only recently uncovered in climate proxies around the world. In this interview, Eos talks to Harunur Rashid about piecing together ancient climes, the effect of abrupt change on historical civilizations, and why younger researchers may be more worried about modern warming than their teachers.

  7. Modeling Past Abrupt Climate Changes

    DEFF Research Database (Denmark)

    Marchionne, Arianna

    According to Milankovitch theory of ice ages, glacial cycles are driven by variations in the insolation, i.e. the amount of the incoming solar radiation reaching the Earth. These variations are associated with variations of the Earth's orbit. Many attempts have been made to identify the in uence...... to the orbitally driven variations in insolation. However, the relationship is far from linear, and insolation alone can not explain the climatic variability seen in the records. In the rst part of this thesis, we discuss the possible dynamical mechanisms for linking the frequencies observed in the records...

  8. Approaching the Edge of Abrupt Climate Change

    Science.gov (United States)

    Ramadhin, C.; Yi, C.

    2015-12-01

    The phenomenon of Abrupt Climate Change (ACC) became evident as paleoclimate data analyses began revealing that Earth's climate has the ability to rapidly switch from one state to the next in just a few decades after thresholds are crossed. Previously paleo-climatologists thought these switches were gradual but now there is growing concern to identify thresholds and the dominant feedback mechanisms that propel systems toward thresholds. Current human civilization relies heavily on climate stability and ACC threatens immense disruption with potentially disastrous consequences for all ecosystems. Therefore, prediction of the climate system's approach to threshold values would prove vital for the resilience of civilization through development of appropriate adaptation strategies when that shift occurs. Numerous studies now establish that earth systems are experiencing dramatic changes both by system interactions and anthropogenic sources adding urgency for comprehensive knowledge of tipping point identification. Despite this, predictions are difficult due to the immensity of interactions among feedback mechanisms. In this paper, we attempt to narrow this broad spectrum of critical feedback mechanisms by reviewing several publications on role of feedbacks in initiating past climate transitions establishing the most critical ones and significance in current climate changes. Using a compilation of paleoclimate datasets we compared the rates of deglaciations with that of glacial inceptions, which are approximately 5-10 times slower. We hypothesize that the critical feedbacks are unique to each type of transition such that warmings are dominated by the ice-albedo feedback while coolings are a combination of temperature - CO2 and temperature-precipitation followed by the ice-albedo feedbacks. Additionally, we propose the existence of a commonality in the dominant trigger feedbacks for astronomical and millennial timescale abrupt climate shifts and as such future studies

  9. The Role of the Tropics in Abrupt Climate Changes

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, Alexey [Yale University

    2013-12-07

    Topics addressed include: abrupt climate changes and ocean circulation in the tropics; what controls the ocean thermal structure in the tropics; a permanent El Niño in paleoclimates; the energetics of the tropical ocean.

  10. Sea-ice switches and abrupt climate change.

    Science.gov (United States)

    Gildor, Hezi; Tziperman, Eli

    2003-09-15

    We propose that past abrupt climate changes were probably a result of rapid and extensive variations in sea-ice cover. We explain why this seems a perhaps more likely explanation than a purely thermohaline circulation mechanism. We emphasize that because of the significant influence of sea ice on the climate system, it seems that high priority should be given to developing ways for reconstructing high-resolution (in space and time) sea-ice extent for past climate-change events. If proxy data can confirm that sea ice was indeed the major player in past abrupt climate-change events, it seems less likely that such dramatic abrupt changes will occur due to global warming, when extensive sea-ice cover will not be present.

  11. The role of the thermohaline circulation in abrupt climate change.

    Science.gov (United States)

    Clark, Peter U; Pisias, Nicklas G; Stocker, Thomas F; Weaver, Andrew J

    2002-02-21

    The possibility of a reduced Atlantic thermohaline circulation in response to increases in greenhouse-gas concentrations has been demonstrated in a number of simulations with general circulation models of the coupled ocean-atmosphere system. But it remains difficult to assess the likelihood of future changes in the thermohaline circulation, mainly owing to poorly constrained model parameterizations and uncertainties in the response of the climate system to greenhouse warming. Analyses of past abrupt climate changes help to solve these problems. Data and models both suggest that abrupt climate change during the last glaciation originated through changes in the Atlantic thermohaline circulation in response to small changes in the hydrological cycle. Atmospheric and oceanic responses to these changes were then transmitted globally through a number of feedbacks. The palaeoclimate data and the model results also indicate that the stability of the thermohaline circulation depends on the mean climate state.

  12. Abrupt climate change and thermohaline circulation: Mechanisms and predictability

    OpenAIRE

    J. Marotzke

    2000-01-01

    The ocean's thermohaline circulation has long been recognized as potentially unstable and has consequently been invoked as a potential cause of abrupt climate change on all timescales of decades and longer. However, fundamental aspects of thermohaline circulation changes remain poorly understood.

  13. Abrupt climate change and thermohaline circulation: mechanisms and predictability.

    Science.gov (United States)

    Marotzke, J

    2000-02-15

    The ocean's thermohaline circulation has long been recognized as potentially unstable and has consequently been invoked as a potential cause of abrupt climate change on all timescales of decades and longer. However, fundamental aspects of thermohaline circulation changes remain poorly understood.

  14. The Atlantic Meridional Overturning Circulation and Abrupt Climate Change

    Science.gov (United States)

    Lynch-Stieglitz, Jean

    2017-01-01

    Abrupt changes in climate have occurred in many locations around the globe over the last glacial cycle, with pronounced temperature swings on timescales of decades or less in the North Atlantic. The global pattern of these changes suggests that they reflect variability in the Atlantic meridional overturning circulation (AMOC). This review examines the evidence from ocean sediments for ocean circulation change over these abrupt events. The evidence for changes in the strength and structure of the AMOC associated with the Younger Dryas and many of the Heinrich events is strong. Although it has been difficult to directly document changes in the AMOC over the relatively short Dansgaard-Oeschger events, there is recent evidence supporting AMOC changes over most of these oscillations as well. The lack of direct evidence for circulation changes over the shortest events leaves open the possibility of other driving mechanisms for millennial-scale climate variability.

  15. Mechanisms of abrupt climate change of the last glacial period

    Science.gov (United States)

    Clement, Amy C.; Peterson, Larry C.

    2008-12-01

    More than a decade ago, ice core records from Greenland revealed that the last glacial period was characterized by abrupt climate changes that recurred on millennial time scales. Since their discovery, there has been a large effort to determine whether these climate events were a global phenomenon or were just confined to the North Atlantic region and also to reveal the mechanisms that were responsible for them. In this paper, we review the available paleoclimate observations of abrupt change during the last glacial period in order to place constraints on possible mechanisms. Three different mechanisms are then reviewed: ocean thermohaline circulation, sea ice feedbacks, and tropical processes. Each mechanism is tested for its ability to explain the key features of the observations, particularly with regard to the abruptness, millennial recurrence, and geographical extent of the observed changes. It is found that each of these mechanisms has explanatory strengths and weaknesses, and key areas in which progress could be made in improving the understanding of their long-term behavior, both from observational and modeling approaches, are suggested. Finally, it is proposed that a complete understanding of the mechanisms of abrupt change requires inclusion of processes at both low and high latitudes, as well as the potential for feedbacks between them. Some suggestions for experimental approaches to test for such feedbacks with coupled climate models are given.

  16. An interhemispheric mechanism for glacial abrupt climate change

    Science.gov (United States)

    Banderas, Rubén; Alvarez-Solas, Jorge; Robinson, Alexander; Montoya, Marisa

    2015-05-01

    The last glacial period was punctuated by abrupt climate changes that are widely considered to result from millennial-scale variability of the Atlantic meridional overturning circulation (AMOC). However, the origin of these AMOC reorganizations remains poorly understood. The climatic connection between both hemispheres indicated by proxies suggests that the Southern Ocean (SO) could regulate this variability through changes in winds and atmospheric CO concentration. Here, we investigate this hypothesis using a coupled climate model forced by prescribed CO and SO wind-stress variations. We find that the AMOC exhibits an oscillatory behavior between weak and strong circulation regimes which is ultimately caused by changes in the meridional density gradient of the Atlantic Ocean. The evolution of the simulated climatic patterns matches the amplitude and timing of the largest events that occurred during the last glacial period and their widespread climatic impacts. Our results suggest the existence of an internal interhemispheric oscillation mediated by the bipolar seesaw that could promote glacial abrupt climate changes through variations in atmospheric CO levels, the strength of the SO winds and AMOC reorganizations, and provide an explanation for the pervasive Antarctic-like climate signal found in proxy records worldwide.

  17. Detecting abrupt climate changes on different time scales

    Science.gov (United States)

    Matyasovszky, István

    2011-10-01

    Two concepts are introduced for detecting abrupt climate changes. In the first case, the sampling frequency of climate data is high as compared to the frequency of climate events examined. The method is based on a separation of trend and noise in the data and is applicable to any dataset that satisfies some mild smoothness and statistical dependence conditions for the trend and the noise, respectively. We say that an abrupt change occurs when the first derivative of the trend function has a discontinuity and the task is to identify such points. The technique is applied to Northern Hemisphere temperature data from 1850 to 2009, Northern Hemisphere temperature data from proxy data, a.d. 200-1995 and Holocene δ18O values going back to 11,700 years BP. Several abrupt changes are detected that are, among other things, beneficial for determining the Medieval Warm Period, Little Ice Age and Holocene Climate Optimum. In the second case, the sampling frequency is low relative to the frequency of climate events studied. A typical example includes Dansgaard-Oeschger events. The methodology used here is based on a refinement of autoregressive conditional heteroscedastic models. The key element of this approach is the volatility that characterises the time-varying variance, and abrupt changes are defined by high volatilities. The technique applied to δ18O values going back to 122,950 years BP is suitable for identifying DO events. These two approaches for the two cases are closely related despite the fact that at first glance, they seem quite different.

  18. Response of seafloor ecosystems to abrupt global climate change

    Science.gov (United States)

    Moffitt, Sarah E.; Hill, Tessa M.; Roopnarine, Peter D.; Kennett, James P.

    2015-04-01

    Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans (Mollusca, Echinodermata, Arthropoda, and Annelida; >5,400 fossils and trace fossils) in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record, from 16,100 to 3,400 y ago, demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to 1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems.

  19. Response of seafloor ecosystems to abrupt global climate change.

    Science.gov (United States)

    Moffitt, Sarah E; Hill, Tessa M; Roopnarine, Peter D; Kennett, James P

    2015-04-14

    Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. Thus far, this knowledge has been largely restricted to investigations using Foraminifera, with little being known about ecosystem-scale responses to abrupt, climate-forced deoxygenation. We here present high-resolution records based on the first comprehensive quantitative analysis, to our knowledge, of changes in marine metazoans (Mollusca, Echinodermata, Arthropoda, and Annelida; >5,400 fossils and trace fossils) in response to the global warming associated with the last glacial to interglacial episode. The molluscan archive is dominated by extremophile taxa, including those containing endosymbiotic sulfur-oxidizing bacteria (Lucinoma aequizonatum) and those that graze on filamentous sulfur-oxidizing benthic bacterial mats (Alia permodesta). This record, from 16,100 to 3,400 y ago, demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to 1,000 y, and illustrate the crucial role of climate and oceanographic change in driving long-term successional changes in ocean ecosystems.

  20. Dynamic response of desert wetlands to abrupt climate change.

    Science.gov (United States)

    Springer, Kathleen B; Manker, Craig R; Pigati, Jeffrey S

    2015-11-24

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated (14)C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming.

  1. Dynamic response of desert wetlands to abrupt climate change

    Science.gov (United States)

    Springer, Kathleen; Manker, Craig; Pigati, Jeff

    2015-01-01

    Desert wetlands are keystone ecosystems in arid environments and are preserved in the geologic record as groundwater discharge (GWD) deposits. GWD deposits are inherently discontinuous and stratigraphically complex, which has limited our understanding of how desert wetlands responded to past episodes of rapid climate change. Previous studies have shown that wetlands responded to climate change on glacial to interglacial timescales, but their sensitivity to short-lived climate perturbations is largely unknown. Here, we show that GWD deposits in the Las Vegas Valley (southern Nevada, United States) provide a detailed and nearly complete record of dynamic hydrologic changes during the past 35 ka (thousands of calibrated 14C years before present), including cycles of wetland expansion and contraction that correlate tightly with climatic oscillations recorded in the Greenland ice cores. Cessation of discharge associated with rapid warming events resulted in the collapse of entire wetland systems in the Las Vegas Valley at multiple times during the late Quaternary. On average, drought-like conditions, as recorded by widespread erosion and the formation of desert soils, lasted for a few centuries. This record illustrates the vulnerability of desert wetland flora and fauna to abrupt climate change. It also shows that GWD deposits can be used to reconstruct paleohydrologic conditions at millennial to submillennial timescales and informs conservation efforts aimed at protecting these fragile ecosystems in the face of anthropogenic warming.

  2. Spontaneous abrupt climate change due to an atmospheric blocking–sea-ice–ocean feedback in an unforced climate model simulation

    NARCIS (Netherlands)

    Drijfhout, S.S.; Gleeson, E.; Dijkstra, H.A.; Livina, V.

    2013-01-01

    Abrupt climate change is abundant in geological records, but climate models rarely have been able to simulate such events in response to realistic forcing. Here we report on a spontaneous abrupt cooling event, lasting for more than a century, with a temperature anomaly similar to that of the Little

  3. Modeling geologically abrupt climate changes in the Miocene

    Directory of Open Access Journals (Sweden)

    B. J. Haupt

    2010-12-01

    Full Text Available The gradual cooling of the Cenozoic, including the Miocene epoch, was punctuated by many geologically abrupt warming and cooling episodes – strong deviations from the cooling trend with time span of ten to hundred thousands of years. Our working hypothesis is that some of those warming episodes at least partially might have been caused by dynamics of the emerging Antarctic Ice Sheet, which, in turn, might have caused strong changes of sea surface salinity in the Miocene Southern Ocean. Feasibility of this hypothesis is explored in a series of coupled ocean-atmosphere computer experiments. The results suggest that relatively small and geologically short-lived changes in freshwater balance in the Southern Ocean could have significantly contributed to at least two prominent warming episodes in the Miocene. Importantly, the experiments also suggest that the Southern Ocean was more sensitive to the salinity changes in the Miocene than today, which can attributed to the opening of the Central American Isthmus as a major difference between the Miocene and the present-day ocean-sea geometry.

  4. Detection and attribution of abrupt climate changes in the last one hundred years

    Institute of Scientific and Technical Information of China (English)

    Zhang Wen; Wan Shi-Quan

    2008-01-01

    Based on physical backgrounds, the four time series of the Guliya (Tibetan plateau) ice core (GIC) δ18O, and three natural factors, I.e. The rotation rate of earth, sunspots, and El Nino-Southern Oscillation (ENSO) signals, are decomposed into two hierarchies, I.e. More and less than 10-year hierarchies respectively, and then the running t-test is used to reanalyse the data before and after filtering with the purpose of investigating the contribution of natural factors to the abrupt climate changes in the last one hundred years. The results show that the GIC δ18O evolved with a quasi-period of 7-9 years, and the abrupt climate changes in the early 1960s and in the period from the end of the 1970s to the beginning of the 1980s resulted from the joint effect of the two hierarchies, in other words, the two interdecadal abrupt changes of climate in the last one hundred years were global. The interannual variations of ENSO and sunspots were the important triggering factors for the abrupt climate changes in the last one hundred years. At the same time, the method of Information Transfer (IT) is employed to estimate the contributions of ENSO signals and sunspots activities to the abrupt climate changes, and it is found that the contribution of the interannual variation of ENSO signals is relatively large.

  5. Abrupt Climate Change: A Magnetic Coupling Model (MCM) Prediction.

    Science.gov (United States)

    Ely, John T. A.

    2002-04-01

    Recent findings [p.8 ISBN 0-309-07434-7] show major climate changes often occur in a decade. This is another of many MCM predictions (see refs). All of them tested from 1968 to date have been proven, including: Global warming is real and driven by fossil fuel (1970's); This CO2 forcing has ended Major Ice Ages; All Major and Minor Ice Ages are caused by decreases in existing (primarily subvisible and other thin, especially newly forming) cirrus at mid to high geomagnetic latitudes; Ionization of the atmosphere near 250 grams per square cm depth by GCR (galactic cosmic ray protons circa 1 gev) cause cirrus depression; Ice cores and other proxy records show ice ages exhibit increased beryllium-10, carbon-14, etc, due to GCR. As noted in the Mar and Apr abstracts, the MCM predictable climate ended in 2000, following over 30 yrs of our ignoring its easily testable warnings re fossil fuel. Hence, we now face the somber question of whether human intervention is still possible in a CO2 Runaway and sea level rise that may be on a decade time scale. [Ely, Session A8, APS Mtg, Seattle, Mar 01; Ely, Session H14.013, APS Mtg, Apr 01; MCM pub list http://faculty.washington.edu/ely/MCM.html

  6. Catalogue of abrupt shifts in Intergovernmental Panel on Climate Change climate models

    NARCIS (Netherlands)

    Drijfhout, S.; Bathiany, S.; Beaulieu, N.; Brovkin, V.; Claussen, M.; Huntingford, C.; Scheffer, M.; Sgubin, G.; Swingedouw, D.

    2015-01-01

    Abrupt transitions of regional climate in response to the gradual rise in atmospheric greenhouse gas concentrations are notoriously difficult to foresee. However, such events could be particularly challenging in view of the capacity required for society and ecosystems to adapt to them. We present,

  7. Abrupt climate change: chaos and order at orbital and millennial scales

    Science.gov (United States)

    Rial, J. A.

    2004-04-01

    Successful prediction of future global climate is critically dependent on understanding its complex history, some of which is displayed in paleoclimate time series extracted from deep-sea sediment and ice cores. These recordings exhibit frequent episodes of abrupt climate change believed to be the result of nonlinear response of the climate system to internal or external forcing, yet, neither the physical mechanisms nor the nature of the nonlinearities involved are well understood. At the orbital (10 4-10 5 years) and millennial scales, abrupt climate change appears as sudden, rapid warming events, each followed by periods of slow cooling. The sequence often forms a distinctive saw-tooth shaped time series, epitomized by the deep-sea records of the last million years and the Dansgaard-Oeschger (D/O) oscillations of the last glacial. Here I introduce a simplified mathematical model consisting of a novel arrangement of coupled nonlinear differential equations that appears to capture some important physics of climate change at Milankovitch and millennial scales, closely reproducing the saw-tooth shape of the deep-sea sediment and ice core time series, the relatively abrupt mid-Pleistocene climate switch, and the intriguing D/O oscillations. Named LODE for its use of the logistic-delayed differential equation, the model combines simplicity in the formulation (two equations, small number of adjustable parameters) and sufficient complexity in the dynamics (infinite-dimensional nonlinear delay differential equation) to accurately simulate details of climate change other simplified models cannot. Close agreement with available data suggests that the D/O oscillations are frequency modulated by the third harmonic of the precession forcing, and by the precession itself, but the entrained response is intermittent, mixed with intervals of noise, which corresponds well with the idea that the climate operates at the edge between chaos and order. LODE also predicts a persistent

  8. Abrupt climate change and collapse of ancient civilizations at 2200BC-2000BC

    Institute of Scientific and Technical Information of China (English)

    WANG Shaowu

    2005-01-01

    Plentiful evidence of historical, archaeological and palaeoclimatic studies proved that an abrupt change from wetter to drier climate occurred over the Nile Valley, the Mesopotamia, the Indus Valley and Huanghe River Valley at 2200BC-2000BC. The abrupt change was developed based on the general lowering of temperature in the middle latitudes, and was a strong cold event since the beginning of the Megathermal (8.5-3.0 kaBP). Collapse of Nile civilization appeared at the First Intermediate Period (2181BC-2040BC). Civilization of Mesopotamia began collapse following the disintegration of Akkadian Empire. This process lasted to the foundation of Babylon Kingdom from 2200BC to 1900BC. Indus civilization abruptly fell off at 1800BC. A widespread alternation of archaeological cultures happened in China at ca. 2000BC except only in its central part. Longsheng culture was replaced by the Erlitou culture, which is now acknowledged in China as Xia Culture. Foundation of Xia Dynasty at 2070BC opened a new chapter in the development of Chinese civilization. Studies indicated that abrupt climate change may be caused by the weakening of the Thermohaline Circulation (THC).

  9. What if ... abrupt and extreme climate change? Programme of VAM (Vulnerability, Adaptation, Mitigation)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-10-15

    A number of researchers from different social scientific disciplines present a view in response to the question 'what will happen in our society if the climate suddenly changes?'. They answer questions such as: How will people respond to real risks such as imminent flooding? What are the economic consequences? How will it affect sectors such as inland shipping and coastal tourism? What are the costs of adapting our country to rising sea levels or sudden cold? As a society what do we consider to be socially and publicly acceptable? Can we still insure ourselves? Who will assume responsibility and what are the tasks of the various parties involved? The book merely sets the scene. Social sciences research into climate change has only just started. Besides providing answers to the question about the social and public implications of abrupt climate change, the book calls for a greater involvement of social scientists in climate change issues.

  10. Simulating the vegetation response in western Europe to abrupt climate changes under glacial background conditions

    Directory of Open Access Journals (Sweden)

    M.-N. Woillez

    2013-03-01

    Full Text Available The last glacial period has been punctuated by two types of abrupt climatic events, the Dansgaard–Oeschger (DO and Heinrich (HE events. These events, recorded in Greenland ice and in marine sediments, involved changes in the Atlantic Meridional Overturning Circulation (AMOC and led to major changes in the terrestrial biosphere. Here we use the dynamical global vegetation model ORCHIDEE to simulate the response of vegetation to abrupt changes in the AMOC strength. We force ORCHIDEE offline with outputs from the IPSL_CM4 general circulation model, in which the AMOC is forced to change by adding freshwater fluxes in the North Atlantic. We investigate the impact of a collapse and recovery of the AMOC, at different rates, and focus on Western Europe, where many pollen records are available for comparison. The impact of an AMOC collapse on the European mean temperatures and precipitations simulated by the GCM is relatively small but sufficient to drive an important regression of forests and expansion of grasses in ORCHIDEE, in qualitative agreement with pollen data for an HE event. On the contrary, a run with a rapid shift of the AMOC to a hyperactive state of 30 Sv, mimicking the warming phase of a DO event, does not exhibit a strong impact on the European vegetation compared to the glacial control state. For our model, simulating the impact of an HE event thus appears easier than simulating the abrupt transition towards the interstadial phase of a DO. For both a collapse or a recovery of the AMOC, the vegetation starts to respond to climatic changes immediately but reaches equilibrium about 200 yr after the climate equilibrates, suggesting a possible bias in the climatic reconstructions based on pollen records, which assume equilibrium between climate and vegetation. However, our study does not take into account vegetation feedbacks on the atmosphere.

  11. Does the trigger for abrupt climate change reside in the ocean or in the atmosphere?

    Science.gov (United States)

    Broecker, W S

    2003-06-06

    Two hypotheses have been put forward to explain the large and abrupt climate changes that punctuated glacial time. One attributes such changes to reorganizations of the ocean's thermohaline circulation and the other to changes in tropical atmosphere-ocean dynamics. In an attempt to distinguish between these hypotheses, two lines of evidence are examined. The first involves the timing of the freshwater injections to the northern Atlantic that have been suggested as triggers for the global impacts associated with the Younger Dryas and Heinrich events. The second has to do with evidence for precursory events associated with the Heinrich ice-rafted debris layers in the northern Atlantic and with the abrupt Dansgaard-Oeschger warmings recorded in the Santa Barbara Basin.

  12. North Atlantic ocean circulation and abrupt climate change during the last glaciation.

    Science.gov (United States)

    Henry, L G; McManus, J F; Curry, W B; Roberts, N L; Piotrowski, A M; Keigwin, L D

    2016-07-29

    The most recent ice age was characterized by rapid and hemispherically asynchronous climate oscillations, whose origin remains unresolved. Variations in oceanic meridional heat transport may contribute to these repeated climate changes, which were most pronounced during marine isotope stage 3, the glacial interval 25 thousand to 60 thousand years ago. We examined climate and ocean circulation proxies throughout this interval at high resolution in a deep North Atlantic sediment core, combining the kinematic tracer protactinium/thorium (Pa/Th) with the deep water-mass tracer, epibenthic δ(13)C. These indicators suggest reduced Atlantic overturning circulation during every cool northern stadial, with the greatest reductions during episodic Hudson Strait iceberg discharges, while sharp northern warming followed reinvigorated overturning. These results provide direct evidence for the ocean's persistent, central role in abrupt glacial climate change. Copyright © 2016, American Association for the Advancement of Science.

  13. Influence of external forcings on abrupt millennial-scale climate changes: a statistical modelling study

    Science.gov (United States)

    Mitsui, Takahito; Crucifix, Michel

    2016-07-01

    The last glacial period was punctuated by a series of abrupt climate shifts, the so-called Dansgaard-Oeschger (DO) events. The frequency of DO events varied in time, supposedly because of changes in background climate conditions. Here, the influence of external forcings on DO events is investigated with statistical modelling. We assume two types of simple stochastic dynamical systems models (double-well potential-type and oscillator-type), forced by the northern hemisphere summer insolation change and/or the global ice volume change. The model parameters are estimated by using the maximum likelihood method with the NGRIP Ca^{2+} record. The stochastic oscillator model with at least the ice volume forcing reproduces well the sample autocorrelation function of the record and the frequency changes of warming transitions in the last glacial period across MISs 2, 3, and 4. The model performance is improved with the additional insolation forcing. The BIC scores also suggest that the ice volume forcing is relatively more important than the insolation forcing, though the strength of evidence depends on the model assumption. Finally, we simulate the average number of warming transitions in the past four glacial periods, assuming the model can be extended beyond the last glacial, and compare the result with an Iberian margin sea-surface temperature (SST) record (Martrat et al. in Science 317(5837): 502-507, 2007). The simulation result supports the previous observation that abrupt millennial-scale climate changes in the penultimate glacial (MIS 6) are less frequent than in the last glacial (MISs 2-4). On the other hand, it suggests that the number of abrupt millennial-scale climate changes in older glacial periods (MISs 6, 8, and 10) might be larger than inferred from the SST record.

  14. Postglacial Human resilience and susceptibility to abrupt climate change new insights from Star Carr

    Science.gov (United States)

    Blockley, Simon; Abrook, Ashley; Bayliss, Alex; Candy, Ian; Conneller, Chantal; Darvill, Chris; Deeprose, Laura; Kearney, Rebecca; Langdon, Pete; Langdon Langdon, Cath; Lincoln, Paul; Macleod, Alison; Matthews, Ian; Palmer, Adrian; Schreve, Danielle; Taylor, Barry; Milner, Nicky

    2017-04-01

    We know little about the lives of the early humans who lived during the early Postglacial period (the Lateglacial and Early Holocene), a time characterised by abrupt climate change after 16,000, which includes a series of abrupt climatic transitions linked to the reorganisation of the global environment after the glacial maximum and the last major global warming event at the onset of the Holocene. The hunter-gatherers who lived during the early Postglacial have been characterised as highly mobile, dispersed and living within small groups, and there is much debate as to how they adapted to climatic and environmental change: did they move in response to climatic transitions (and if so what was the climatic threshold), or instead adapt their lifeways to the new environmental conditions? A key area for examining these ideas is the British Isles as it sits on the Atlantic fringe of Northwest Europe with a climate that is highly responsive to the wider climate forcing experienced in the northern Hemisphere. Furthermore, in this period, Britain is directly linked to continental Europe due to lowered global sea levels allowing for the ease of human migration in and out of this region. In general the British record has been seen as being dominated by abandonment and reoccupation in the Postglacial during periods of climatic transition with hunter-gatherer mobility being closely linked to the prevailing environment. Recent discoveries at the Early Mesolithic site of Star Carr and surrounding area, linked to local and regional climate records, based on isotopic, chironomid and pollen proxy data and dated at high chronological resolution, offer a new picture. Postglacial human occupation of the area commences at the Pleistocene/Holocene transition but is short lived and appears to end close to the Pre-Boreal Oscillation, However, this is followed by a period where hunter-gatherers occupy Star Carr and settle and invest time and effort into building huts and large scale wooden

  15. Holocene Abrupt Climate Change Over NW Iran: The Hand That Rocked The Cradle Of Civilization?

    Science.gov (United States)

    Sharifi, A.; Pourmand, A.; Canuel, E. A.; Ferer-Tyler, E.; Peterson, L. C.; Aichner, B.; Feakins, S. J.; Daryaee, T.; Djamali, M.; Naderi Beni, A.; Lahijani, H. A. K.; Swart, P. K.

    2014-12-01

    Human civilizations around the globe have been influenced by abrupt climate change throughout the Holocene. The paucity of high-resolution palaeoclimate data from the "Cradle of Civilization" in West Asia, however, has limited our ability to evaluate the potential role of Holocene climate variability on early societies. We present a high-resolution, multi-proxy reconstruction of aeolian input and palaeoenvironmental conditions based on a 13-kyr record of ombrotrophic (rain fed) peat from Neor Lake in Northwest Iran. Variations in relative abundances of major and trace elements, total organic carbon (TOC), stable carbon isotopes of TOC (δ13CTOC) and compound-specific leaf wax hydrogen isotope (δD) compositions suggest dry and dusty conditions prevailed during the Younger Dryas, and a substantial increase in atmospheric dust loading and decrease in moisture availability occurred between the early and late Holocene. In addition, variations in radiogenic Sr-Nd-Hf isotopic composition and REE anomalies in samples from Neor peat core indicate significant shifts occurred in source contributions of eolian material to the study area between the Younger Dryas, early and late Holocene. Time-series analysis of aeolian input to NE Iran reveals periodicities at 540, 1050 and 2940 years that correspond with solar variability and internal climate feedbacks identified in other records of Holocene climate change from the northern hemisphere. Transitions in major Mesopotamian and Persian civilizations, including the collapse of the Akkadian empire at 4,200 yr BP, the fall of the Ur III empire at 3,955 yr BP, the fall of Elam empire at 2,500 yr BP and the demise of the Achaemenids around 2,280 BP overlap with major dust events from this study. Several other episodes of enhanced atmospheric dust, however, are not reflected in historical or archaeological accounts of the late Holocene. This indicates either abrupt climate change was not the sole driver of societal changes in the

  16. Abrupt Holocene climate change as an important factor for human migration in West Greenland.

    Science.gov (United States)

    D'Andrea, William J; Huang, Yongsong; Fritz, Sherilyn C; Anderson, N John

    2011-06-14

    West Greenland has had multiple episodes of human colonization and cultural transitions over the past 4,500 y. However, the explanations for these large-scale human migrations are varied, including climatic factors, resistance to adaptation, economic marginalization, mercantile exploration, and hostile neighborhood interactions. Evaluating the potential role of climate change is complicated by the lack of quantitative paleoclimate reconstructions near settlement areas and by the relative stability of Holocene temperature derived from ice cores atop the Greenland ice sheet. Here we present high-resolution records of temperature over the past 5,600 y based on alkenone unsaturation in sediments of two lakes in West Greenland. We find that major temperature changes in the past 4,500 y occurred abruptly (within decades), and were coeval in timing with the archaeological records of settlement and abandonment of the Saqqaq, Dorset, and Norse cultures, which suggests that abrupt temperature changes profoundly impacted human civilization in the region. Temperature variations in West Greenland display an antiphased relationship to temperature changes in Ireland over centennial to millennial timescales, resembling the interannual to multidecadal temperature seesaw associated with the North Atlantic Oscillation.

  17. Abrupt climate-triggered lake ecosystem changes recorded in late glacial lake sediments in northern Poland

    Science.gov (United States)

    Slowinski, M. M.; Zawiska, I.; Ott, F.; Noryskiewicz, A. M.; Apolinarska, K.; Lutynska, M.; Michczynska, D. J.; Brauer, A.; Wulf, S.; Skubala, P.; Blaszkiewicz, M.

    2013-12-01

    The aim of this study was to better understand how local lake ecosystems responded to abrupt climate changes through applying multi-proxy sediment analyses. Therefore, we carried out a detailed and high-resolution case study on the late glacial sediment from the Trzechowskie palaeolake located in the eastern part of the Pomeranian Lakeland, northern Poland. We reconstructed climate induced environmental changes in the paleolake and its catchment using biotic proxies (macrofossils, pollen, cladocera, diatoms, oribatidae mite) and classical geochemical proxies (δ18O, δ13C, loss-on-ignition, CaCO3 content) in combination with high-resolution μ-XRF element core scanning. The core chronology has been established by means of biostratigraphy, AMS 14C-dating on plant macro remains, varve counting in laminated intervals and tephrochronology. The latter was possible by the discovery of the late Allerød Laacher See Tephra for the first time at such eastern location. Biogenic accumulation in the lake started rather late during the lateglacial interstadial at 13903×170 cal yrs BP. The rapid and pronounced cooling at the beginning of the Younger Dryas had a major impact on the lake and its catchment as clearly reflected by both, biotic and geochemical proxies. The depositional environment of the lake abruptly changed from a varved to massive gytjia. The pronounced warming at the demise of Younger Dryas cooling is well-reflected in all environmental indicators but with conspicuous leads and lags reflecting complex responses of lake ecosystems to climate warming. The research was supported by the National Science Centre Poland - NN306085037. This study is a contribution to the Virtual Institute ICLEA (Integrated Climate and Landscape Evolution Analysis) funded by the Helmholtz Association.

  18. Laurentide Ice Sheet meltwater and abrupt climate change during the last glaciation

    Energy Technology Data Exchange (ETDEWEB)

    Hill, H W; Flower, B P; Quinn, T M; Hollander, D J; Guilderson, T P

    2005-10-02

    A leading hypothesis to explain abrupt climate change during the last glacial cycle calls on fluctuations in the margin of the North American Laurentide Ice Sheet (LIS), which may have routed freshwater between the Gulf of Mexico (GOM) and North Atlantic, affecting North Atlantic Deep Water (NADW) variability and regional climate. Paired measurements of {delta}O and Mg/Ca of foraminiferal calcite from GOM sediments reveal five episodes of LIS meltwater input from 28-45 thousand years ago (ka) that do not match the millennial-scale Dansgaard-Oeschger (D/O) warmings recorded in Greenland ice. We suggest that summer melting of the LIS may occur during Antarctic warming and likely contributed to sea-level variability during Marine Isotope Stage 3 (MIS 3).

  19. The Response of First Flowering Dates to Abrupt Climate Change in Beijing

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Phenological data on the First Flowering Date(FFD) of woody plants in Beijing from 1963-2007 are analyzed.The correlation between each species' yearly FFD and the mean monthly temperatures for every year over a 45-year period is used to identify the month in which temperature has the most effect on FFD. Through further analysis,the FFDs of 48 woody plant species are shown to have advanced an average of 5.4 days from 1990-2007 compared to 1963-1989.The results indicate that 70.8%of species flowered significantly earlier(7 days on average) during the period 1990-2007,while only one species(2.1%) flowered significantly later.Moreover,the responses of FFD to climate change are shown to be different in two climatic stages, defined by an abrupt climate change point.Thirty-three species which first flower in March and April are sensitive to temperature are examined.The correlation coefficients between FFD and temperature for 20 species during the latter period(1990-2007) are shown to be larger than during the former period(1963- 1989),with a difference of around -0.87 days per 1℃on average.The paper concludes that with the warming of climate,the linear trend of FFD variation,as well as its responsiveness to temperature,became more prominent during 1990-2007 than 1963-1989.The data analyzed in this study present a strong biological indicator of climate change in Beijing,and provide further confirmation of previous results from regional and local studies across the Northern Hemisphere.Phenophase variations indicate that the climate is changing rapidly.

  20. The Response of First Flowering Dates to Abrupt Climate Change in Beijing

    Institute of Scientific and Technical Information of China (English)

    BAI Jie; GE Quansheng; DAI Junhu

    2011-01-01

    Phenological data on the First Flowering Date (FFD) of woody plants in Beijing from 1963-2007 are analyzed. The correlation between each species' yearly FFD and the mean monthly temperatures for every year over a 45-year period is used to identify the month in which temperature has the most effect on FFD.Through further analysis, the FFDs of 48 woody plant species are shown to have advanced an average of 5.4days from 1990-2007 compared to 1963-1989. The results indicate that 70.8% of species flowered significantly earlier (7 days on average) during the period 1990 2007, while only one species (2.1%) flowered significantly later. Moreover, the responses of FFD to climate change are shown to be different in two climatic stages,defined by an abrupt climate change point. Thirty-three species which first flower in March and April are sensitive to temperature are examined. The correlation coefficients between FFD and temperature for 20species during the latter period (1990-2007) are shown to be larger than during the former period (1963-1989), with a difference of around -0.87 days per 1℃ on average. The paper concludes that with the warming of climate, the linear trend of FFD variation, as well as its responsiveness to temperature, became more prominent during 1990-2007 than 1963-1989. The data analyzed in this study present a strong biological indicator of climate change in Beijing, and provide further confirmation of previous results from regional and local studies across the Northern Hemisphere. Phenophase variations indicate that the climate is changing rapidly.

  1. Abrupt climate changes of the last deglaciation detected in a western Mediterranean forest record

    Directory of Open Access Journals (Sweden)

    W. J. Fletcher

    2009-01-01

    Full Text Available Evidence for abrupt changes in western Mediterranean climate between 20 and 6 cal ka BP is examined in marine core MD95-2043 (Alborán Sea, using pollen data for temperate Mediterranean forest development and pollen-based climate reconstructions using the modern analogue technique (MAT for annual precipitation (Pann and mean temperatures of the coldest and warmest months (MTCO and MTWA. Major climatic shifts with parallel temperature and precipitation changes occurred at the onsets of Heinrich Event 1 (equivalent to the Oldest Dryas, the Bölling-Allerød (BA, and the Younger Dryas (YD. Multi-centennial-scale oscillations in forest development related to regional precipitation (Pann variability occurred throughout the BA, YD, and early Holocene, with drier atmospheric conditions in phase with Lateglacial events of high-latitude cooling including GI-1d (Older Dryas, GI-1b (Intra-Allerød Cold Period and GS-1 (YD, and during Holocene events associated with high-latitude cooling, meltwater pulses and N. Atlantic ice-rafting (events at 11.4, 10.1, 9.3, 8.2 and 7.4 cal ka BP. The forest record also indicates multi-centennial variability within the YD interval and multiple Preboreal climate oscillations. A possible climatic mechanism for the recurrence of dry intervals and an opposed regional precipitation pattern with respect to western-central Europe relates to the dynamics of the jet stream and the prevalence of atmospheric blocking highs. Comparison of radiocarbon and ice-core ages for well-defined climatic transitions in the forest record suggests possible enhancement of marine reservoir ages in the Alborán Sea by ~200 years (surface water age ~600 years during the Lateglacial.

  2. Antarctic Forcing of Abrupt Global Climate Change during Oxygen Isotope Stage 3.

    Science.gov (United States)

    Turney, C. S.; Palmer, J. G.

    2015-12-01

    Contrasting Greenland and Antarctic temperature trends during the late Pleistocene (60 to 11.5 ka) are thought to be driven by imbalances in the rate of formation of North Atlantic and Antarctic deep water (the 'bipolar seesaw'), with millennial-scale cooling Dansgaard-Oeschger (D-O) events in the north leading warming in the south. Robustly testing this paradigm, however, requires a level of chronological precision currently lacking in terrestrial and marine records. Here we report a bidecadally-resolved New Zealand tree-ring sequence spanning two millennia that preserves a record of atmospheric radiocarbon (14C), allowing us to precisely align terrestrial, marine and ice sequences across a period encompassing ice-rafted debris event Heinrich 3 (H3) in the North Atlantic and Antarctic Isotope Maximum 4 (AIM4) in the Southern Hemisphere. We observe no significant difference in atmospheric and marine 14C records across H3 suggesting negligible impact on Atlantic Meridional Overturning Circulation (AMOC) but find that a climate downturn before AIM4 had a global impact, with warming in the North Atlantic (D-O 5.1) and a dramatic change in low latitude hydroclimate. Using the fully coupled CSIRO Mk3L climate system model we find that these trends are consistent with an Antarctic meltwater event propagated globally by atmospheric teleconnections. Our results suggest Southern Ocean dynamics played a significant role in driving global climate change across this period with implications for abrupt events through the late Pleistocene.

  3. Agriculture, Settlement, and Abrupt Climate Change: The 4.2ka BP event in Northern Mesopotamia

    Science.gov (United States)

    Ristvet, L.

    2003-12-01

    An abrupt aridification event at 4200 BP has been recorded in 41 paleoclimate proxies in the Old World, from Kilmanjaro, Tanzania to Rajasthan, India, East Asia and the Pacific. This event is particularly well defined for Western Asia, where it has been associated with the abandonment of settlements across the Fertile Crescent and the collapse of states on the Levantine coast and in the dry-farming plains of Northern Mesopotamia, including the Akkadian Empire. Adaptations to climate change are constrained by both local environmental and social factors. Agriculturalists, especially those living in pre-industrial societies, are particularly susceptible to changes in precipitation. The Tell Leilan Regional Survey, which systematically studied sites in a 1650km2 area of Northeastern Syria, records one set of adaptations to this event in an area where dry-farming provided the subsistence base. The survey transect crosses ecotones, from the present 500mm isohyet in the North to the 250mm isohyet in the South, and contains diverse wadi systems, ground water resources, soil profiles, and an ancient marsh/lake-- all of which allow this region to be taken as a microcosm of Northern Mesopotamia. In order to contextualize our study of human response to abrupt climate change, it is necessary to consider how the economic and social systems that were previously in place were transformed by this event. This study attempts to quantify climate change and model its effects on agricultural, pastoral, and settlement systems in Northeastern Syria from 2400-1700 BC. From 2400-2300 BC, optimal climate conditions coincided with the consolidation of an indigenous state. The next century witnessed the Akkadian conquest and imperialization of the Habur plains, which resulted in both the intensification and extensification of agro-production. During the next 300 years, (2200-1900 BC), rainfall plummeted to 70% of the climatic optimum, triggering the abandonment of cities along with their

  4. A comparison of two methods for detecting abrupt changes in the variance of climatic time series

    CERN Document Server

    Rodionov, Sergei

    2016-01-01

    Two methods for detecting abrupt shifts in the variance, Integrated Cumulative Sum of Squares (ICSS) and Sequential Regime Shift Detector (SRSD), have been compared on both synthetic and observed time series. In Monte Carlo experiments, SRSD outperformed ICSS in the overwhelming majority of the modelled scenarios with different sequences of variance regimes. The SRSD advantage was particularly apparent in the case of outliers in the series. When tested on climatic time series, in most cases both methods detected the same change points in the longer series (252-787 monthly values). The only exception was the Arctic Ocean SST series, when ICSS found one extra change point that appeared to be spurious. As for the shorter time series (66-136 yearly values), ICSS failed to detect any change points even when the variance doubled or tripled from one regime to another. For these time series, SRSD is recommended. Interestingly, all the climatic time series tested, from the Arctic to the Tropics, had one thing in commo...

  5. Abrupt climate changes of the last deglaciation detected in a Western Mediterranean forest record

    Directory of Open Access Journals (Sweden)

    W. J. Fletcher

    2010-04-01

    Full Text Available Abrupt changes in Western Mediterranean climate during the last deglaciation (20 to 6 cal ka BP are detected in marine core MD95-2043 (Alboran Sea through the investigation of high-resolution pollen data and pollen-based climate reconstructions by the modern analogue technique (MAT for annual precipitation (Pann and mean temperatures of the coldest and warmest months (MTCO and MTWA. Changes in temperate Mediterranean forest development and composition and MAT reconstructions indicate major climatic shifts with parallel temperature and precipitation changes at the onsets of Heinrich stadial 1 (equivalent to the Oldest Dryas, the Bölling-Allerød (BA, and the Younger Dryas (YD. Multi-centennial-scale oscillations in forest development occurred throughout the BA, YD, and early Holocene. Shifts in vegetation composition and (Pann reconstructions indicate that forest declines occurred during dry, and generally cool, episodes centred at 14.0, 13.3, 12.9, 11.8, 10.7, 10.1, 9.2, 8.3 and 7.4 cal ka BP. The forest record also suggests multiple, low-amplitude Preboreal (PB climate oscillations, and a marked increase in moisture availability for forest development at the end of the PB at 10.6 cal ka BP. Dry atmospheric conditions in the Western Mediterranean occurred in phase with Lateglacial events of high-latitude cooling including GI-1d (Older Dryas, GI-1b (Intra-Allerød Cold Period and GS-1 (YD, and during Holocene events associated with high-latitude cooling, meltwater pulses and N. Atlantic ice-rafting. A possible climatic mechanism for the recurrence of dry intervals and an opposed regional precipitation pattern with respect to Western-central Europe relates to the dynamics of the westerlies and the prevalence of atmospheric blocking highs. Comparison of radiocarbon and ice-core ages for well-defined climatic transitions in the forest record suggests possible enhancement of marine reservoir ages in the Alboran

  6. The Role of the Tropics in Last Glacial Abrupt Climate Change from a West Antarctic Ice Core

    Science.gov (United States)

    Jones, T. R.; White, J. W. C.; Steig, E. J.; Cuffey, K. M.; Vaughn, B. H.; Morris, V. A.; Vasileios, G.; Markle, B. R.; Schoenemann, S. W.

    2014-12-01

    Debate exists as to whether last glacial abrupt climate changes in Greenland, and associated changes in Antarctica, had a high-latitude or tropical trigger. An ultra high-resolution water isotope record from the West Antarctic Ice Sheet Divide (WAIS Divide) Ice Core Project has been developed with three key water isotope parameters that offer insight into this debate: δD, δ18O, and deuterium excess (dxs). δD and δ18O are a proxy for local temperature and regional atmospheric circulation, while dxs is primarily a proxy for sea surface temperature at the ice core's moisture source(s) (relative humidity and wind speed also play a role). We build on past studies that show West Antarctic climate is modulated by El Niño Southern Oscillation (ENSO) teleconnection mechanisms, which originate in the equatorial Pacific Ocean, to infer how past ENSO changes may have influenced abrupt climate change. Using frequency analysis of the water isotope data, we can reconstruct the amplitude of ENSO-scale climate oscillations in the 2-15 year range within temporal windows as low as 100 years. Our analysis uses a back diffusion model that estimates initial amplitudes before decay in the firn column. We combine δD, δ18O, and dxs frequency analysis to evaluate how climate variability at WAIS Divide is influenced by tropical climate forcing. Our results should ultimately offer insight into the role of the tropics in abrupt climate change.

  7. Lake-Level Responses to Abrupt Climate Changes in North-Central Pennsylvania since >16 ka

    Science.gov (United States)

    Halstead, T. M.; Shuman, B. N.

    2016-12-01

    Water levels in small lakes and ponds have widely responded to late-Quaternary climate changes, and we use a combination of geophysical surveys and sediment cores to reconstruct the hydrologic history of Sunfish Pond near Leroy, Pennsylvania (41°38'N 76°41'W). The small lake sits atop Barclay Mountain, a narrow ridge of the Appalachian Mountains near the southern limit of the Wisconsin glaciation. Ground-penetrating radar (GPR) profiles and a transect of three sediment cores indicate that the shoreline position of the lake has shifted over time with sandy littoral sediments extending outward into the lake stratigraphy, which is primarily composed of organic-rich muds. Calibrated radiocarbon ages from a sediment core collected in 2.25 m of water indicate that the lake formed by ca. 16.1 ka. Deposition of organic-rich muds in the near-shore core indicates moderately high water levels during the period of Heinrich Event 1, the Younger Dryas, and portions of the early Holocene. Sand layers and exceptionally low sediment accumulation rates indicate low water, however, from <16-12.5 ka and again from 5.5-2.8 ka. The water level has been near its modern high level since 2.8 ka based on extensive deposition of rapidly accumulating, organic-rich muds across the basin. The changes coincide with major changes in regional pollen records, and confirm the hydrologic significance of late-Pleistocene abrupt events in the Mid-Atlantic region.

  8. Archaeological and palaeoecological indications of an abrupt climate change in The Netherlands, and evidence for climatological teleconnections around 2650 BP

    NARCIS (Netherlands)

    VanGeel, B; Buurman, J; Waterbolk, HT

    1996-01-01

    A sudden and sharp rise in the C-14 content of the atmosphere, which occurred between ca. 850 and 760 calendar yr BC (ca. 2750-2450 BP on the radiocarbon time-scale), was contemporaneous with an abrupt climate change. In northwest Europe (as indicated by palaeoecological and geological evidence) cli

  9. Archaeological and palaeoecological indications of an abrupt climate change in The Netherlands, and evidence for climatological teleconnections around 2650 BP

    NARCIS (Netherlands)

    VanGeel, B; Buurman, J; Waterbolk, HT

    1996-01-01

    A sudden and sharp rise in the C-14 content of the atmosphere, which occurred between ca. 850 and 760 calendar yr BC (ca. 2750-2450 BP on the radiocarbon time-scale), was contemporaneous with an abrupt climate change. In northwest Europe (as indicated by palaeoecological and geological evidence)

  10. High-resolution Greenland Ice Core data show abrupt climate change happens in few years

    DEFF Research Database (Denmark)

    Steffensen, Jørgen Peder; Andersen, Katrine Krogh; Bigler, Matthias

    2008-01-01

    The last two abrupt warmings at the onset of our present warm interglacial period, interrupted by the Younger Dryas cooling event, were investigated at high temporal resolution from the North Greenland Ice Core Project ice core. The deuterium excess, a proxy of Greenland precipitation moisture......, reflecting the wetting of Asian deserts. A northern shift of the Intertropical Convergence Zone could be the trigger of these abrupt shifts of Northern Hemisphere atmospheric circulation, resulting in changes of 2 to 4 kelvin in Greenland moisture source temperature from one year to the next....

  11. Iceberg discharges and oceanic circulation changes during glacial abrupt climate changes

    Science.gov (United States)

    Alvarez-Solas, Jorge; Robinson, Alexander; Banderas, Rubén; Montoya, Marisa

    2015-04-01

    Proxy data reveal the existence of episodes of increased deposition of ice-rafted debris in the North Atlantic Ocean during the last glacial period. These are interpreted as massive iceberg discharges mainly from the Laurentide Ice Sheet. Although these have long been attributed to self-sustained ice sheet oscillations, growing evidence points to an active role of the oceanic circulation. Here we will present simulations of the last glacial period carried out with a hybrid ice sheet-ice shelf model. Two mechanisms producing iceberg discharges are compared. First, we reproduce the classic binge-purge by which the iceberg surges are produced thanks to the existence of an internal thermo-mechanical feedback that allows the ice sheet to behave under an oscillatory regime. Second, our ice-sheet model is forced by an oceanic warming index derived from proxy data that accounts for the impact of past ocean circulation changes on ocean temperatures. In this case, the model generates a time series of iceberg calving that agrees with ice-rafted debris records over the past 80 ka. We compare the two theories and discuss their advantages and weaknesses in terms of both the robustness of the physics on which they are based and their comparison with proxies. This comparison highlights the importance of considering past oceanic circulation changes in order to understand the ice-sheet dynamics. However, the ultimate processes determining abrupt changes in the Atlantic Meridional Overturning Circulation (AMOC) remain elusive. Therefore we will also analyze several proposed mechanisms that aims to explain such AMOC reorganizations, focusing on those that do not require freshwater flux forcing.

  12. Abrupt Climate Change Caused by Global Fires from a Large Meteor Impact

    Science.gov (United States)

    Bardeen, C.; Toon, O. B.; Garcia, R. R.; Otto-Bliesner, B. L.; Wolf, E. T.

    2015-12-01

    Global or near-global fires like those that are thought to have occurred after the Chicxulub asteroid impact are associated with abrupt climate change and the K-Pg mass extinction event. Using the Community Earth System Model (CESM), a three-dimensional coupled climate model with interactive chemistry, we have simulated the climate response to global fires assuming a burden of 70,000 Tg, as estimated from the K-Pg layer sediments by Wolbach et al. (1988). Soot aerosols are lofted by solar heating and remain in the atmosphere for about 6 years, warming the stratosphere by more than 240 K and suppressing completely solar radiation at the surface for 2 years. Global average land surface temperatures cool by -28 K after 3 years and ocean temperatures by -11 K after 4 years. Precipitation is reduced by 80 % for 5 years, and the ozone column is reduced by 80 % for 4 years. The tropical tropopause cold point disappears for a few years, leading to water vapor mixing ratios of > 1000 ppmv in the stratosphere. There is a rapid recovery around year 6, when the soot is removed by wet deposition as stratospheric water condenses and precipitates, but this is followed by a peak in the UV Index in the tropics of over 40 before stratospheric ozone recovers. Ocean temperature cools by more than -2 K to a depth of 300 m, and sea ice develops in the Black Sea, Caspian Sea, and Baltic Sea. Global fires, two years of darkness, extreme surface cooling, significant ocean cooling, increases in sea ice extent and a large short-term increase in UV Index would have been catastrophic for many life forms. This work is the first step in an effort to simulate the climatic effects of all of the aerosols and gases that may have been generated by the Chicxulub impact in a model that has been configured for late-Cretaceous conditions to help assess the role of the Chicxulub impact in the K-Pg extinction.

  13. Abrupt North Atlantic circulation changes in response to gradual CO2 forcing in a glacial climate state

    Science.gov (United States)

    Zhang, Xu; Knorr, Gregor; Lohmann, Gerrit; Barker, Stephen

    2017-07-01

    Glacial climate is marked by abrupt, millennial-scale climate changes known as Dansgaard-Oeschger cycles. The most pronounced stadial coolings, Heinrich events, are associated with massive iceberg discharges to the North Atlantic. These events have been linked to variations in the strength of the Atlantic meridional overturning circulation. However, the factors that lead to abrupt transitions between strong and weak circulation regimes remain unclear. Here we show that, in a fully coupled atmosphere-ocean model, gradual changes in atmospheric CO2 concentrations can trigger abrupt climate changes, associated with a regime of bi-stability of the Atlantic meridional overturning circulation under intermediate glacial conditions. We find that changes in atmospheric CO2 concentrations alter the transport of atmospheric moisture across Central America, which modulates the freshwater budget of the North Atlantic and hence deep-water formation. In our simulations, a change in atmospheric CO2 levels of about 15 ppmv--comparable to variations during Dansgaard-Oeschger cycles containing Heinrich events--is sufficient to cause transitions between a weak stadial and a strong interstadial circulation mode. Because changes in the Atlantic meridional overturning circulation are thought to alter atmospheric CO2 levels, we infer that atmospheric CO2 may serve as a negative feedback to transitions between strong and weak circulation modes.

  14. Insolation and Abrupt Climate Change Effects on the Western Pacific Maritime Monsoon

    Science.gov (United States)

    Partin, J. W.; Quinn, T. M.; Shen, C.; Cardenas, M.; Siringan, F. P.; Hori, M.; Okumura, Y.; Banner, J. L.; Lin, K.; Jiang, X.; Taylor, F. W.

    2013-12-01

    Many monsoon-sensitive paleoclimate archives capture the response of the Asian-Australian monsoon system to changes in summer insolation, as well as abrupt climate changes such as the Younger Dryas (YD). The response is commonly a direct one in Holocene and YD archives. In the case of insolation, increased summer insolation leads to increased monsoon rainfall over land, as captured in stalagmite δ18O records from Oman and China. We evaluate this direct response using maritime stalagmite records from the island of Palawan, Philippines (10 N, 119 E). The wet season in Palawan occurs over the same months (June-October) as in Oman, India and China. Therefore, we expected the Palawan stalagmite δ18O record, a proxy of rainfall, to have a similar response to changing insolation and hence, a trend of decreasing monsoon rainfall over the Holocene. However, the Holocene trend in two partially replicated stalagmite δ18O records is opposite to that expected: rainfall increases over the Holocene, despite the decrease of summer insolation over the Holocene. We interpret the Holocene trend observed at Palawan to be the result of an increase in the maritime monsoon that balances the reduction in the land monsoon; an interpretation that is consistent with previously published results from coupled ocean-atmosphere general circulation model runs. Seawater δ18O reconstructions from marine sediment cores in the western tropical Pacific contain a freshening trend over the Holocene, also supporting the hypothesis of increase maritime monsoon rainfall. The direct relationship between monsoon rainfall over land as recorded in the YD interval in Chinese stalagmite records is also observed in maritime monsoon rainfall during the YD at Palawan: both records get drier during the YD cold interval. This agreement between YD stalagmite records from China and Palawan contrasts sharply with the inverse relationship between these records over the Holocene. We further investigate the nature of

  15. Abrupt climate-induced changes in carbonate burial in the Arabian Sea: Causes and consequences.

    Digital Repository Service at National Institute of Oceanography (India)

    Naidu, P.D.; Singh, A.D.; Ganeshram, R.S.; Bharti, S.K.

    teleconnections. We suggest that the role of aragonite carbonate production and burial in margins and the resultant CO2 climate feedback to rapid climate changes remains poorly constrained....

  16. Slow Onsets, Abrupt Changes, and Fast Reflexes: Learning from Climate Hazards in a Changing World

    Science.gov (United States)

    Pulwarty, R. S.

    2016-12-01

    Adaptation is higher than ever before on the global agenda. Awareness of risks across the weather-climate continuum has increased pressure for information to support planning under changing rates and emergence of multiple hazards (e.g. drought, heat waves, floods). In recognition of this demand, the global community is developing a Global Framework for Climate Services, implementing the Sendai Framework on disaster risk reduction, and formulating climate-sensitive development and research initiatives aimed at nations and communities. The gap between conceptual feasibility and practical implementation remains immense. One of Gilbert White's many important contributions was in developing a framework for structuring adjustment decisions in the context of longer-term risks. The physical environment at a given stage of technology sets the theoretical range of choice while the practical range of choice is set by culture, capacity and institutions. These factors facilitate or impede efficient and equitable responses, with the latter being key in the underestimation of the complexities of adaptation. This presentation will focus on the scientific research, monitoring and information needed to address challenges in (1) Understanding thresholds in the relationship between physical and social changes, including those in connected systems such as water, food and energy, (2) Designing and diffusion of decision support tools and smart practices, and (3) Understanding the links between capacity-building and implementation, including the need to focus researchers and institutions on improving decision quality (not just meeting "user needs"). The author will engage the audience in a discussion of the drivers of social transitions and transformations, drawing on cases from around the world. Key questions, include "What leads to proactive collaboration and action?"; "How often should we revise our assumptions about the direction and magnitude of changes as events unfold?"; and "What

  17. Variability of oceanic productivity in the North Atlantic during abrupt climate changes (Heinrich Events)

    Science.gov (United States)

    Nave, S.; Labeyrie, L.; Gherardi, J.; Cortijo, E.; Abrantes, F.; Kissel, C.

    2006-12-01

    Evidences of strong millennial-scale climate variability, especially marked during MIS3, have been reported worldwide in high-resolution records. These pronounced climate changes, known as Dansgaard-Oeschger cycles, are characterized by sudden shifts in temperature, dust content and concentration of methane. Some of the longest Dansgaard-Oescher stadials are closely related to massive iceberg surges, the Heinrich Events (HE), recognized by anomalous concentrations in ice-rafted debris in six peculiar layers in the North Atlantic. Besides the well-documented changes in hydrology, these iceberg discharges had probably a major impact on the marine ecosystem, but data to constrain this variability is lacking. In order to further our understanding on productivity feedbacks to massive iceberg discharges and associated hydrologic adjustments, we have done a high-resolution diatom and organic carbon analysis focused on 7 sedimentary sequences between 40ºN and 65ºN, each of them representative of a North Atlantic region. This study was conducted over two abrupt climate events of the last glacial period, Heinrich Event 1 (H1) and Heinrich Event 4 (H4). Our results show that during H4 event, productivity decreased drastically at all latitudes. No major blooms of siliceous phytoplankton were recorded during iceberg discharges, and hence production resulting from high nutrient supply does not seem to have occurred during HE as suggested by previous studies (Sancetta, 1992). Instead, the severe productivity decrease during H4 could be due to the establishment of a strong halocline and the consequent slowdown of the thermohaline circulation (reducing the mixed layer and therefore preventing the nutrient supply from deeper waters to the upper layer). However, during H1, although hydrologically similar, productivity was apparently not affected in northern latitudes, showing a progressive increase during the deglaciation period. Hence, our results suggest that the orbital forcing

  18. Abrupt climate change and high to low latitude teleconnections as simulated in climate models

    DEFF Research Database (Denmark)

    Cvijanovic, Ivana

    of the present day atmospheric mid-latitude energy transport compared to that of the Last Glacial Maximum, suggesting its ability to reorganize more easily and thereby dampen high latitude temperature anomalies that could arise from changes in the oceanic transport. The role of tropical SSTs in the tropical...... precipitation shifts was further re-examined in idealized simulations with the fixed tropical sea surface temperatures, showing that the SST changes are fundamental to the tropical precipitation shifts. Regarding the high latitude energy loss, it was shown that the main energy compensation comes from...... the southern tropics, with the energy gain originating from the cloud radiative feedbacks, temperature and longwave water vapor feedbacks. Extended consideration of the various scenarios that can induce the southward precipitation shifts showed that the Southern Hemisphere warming simulations, in addition...

  19. Simulating the vegetation response to abrupt climate changes under glacial conditions with the ORCHIDEE/IPSL models

    Directory of Open Access Journals (Sweden)

    M.-N. Woillez

    2012-09-01

    Full Text Available The last glacial period has been punctuated by two types of abrupt climatic events, the Dansgaard-Oeschger (DO and Heinrich (HE events. These events, recorded in Greenland ice and in marine sediments, involved changes in the Atlantic Meridional Overturning Circulation (AMOC and led to major changes in the terrestrial biosphere.

    Here we use the dynamical global vegetation model ORCHIDEE to simulate the response of vegetation to abrupt changes in the AMOC strength. To do so, we force ORCHIDEE off-line with outputs from the IPSL_CM4 general circulation model, in which we have forced the AMOC to change by adding freshwater fluxes in the North Atlantic. We investigate the impact of a collapse and recovery of the AMOC, at different rates, and focus on Western Europe, where many pollen records are available to compare with.

    The impact of an AMOC collapse on the European mean temperatures and precipitations simulated by the GCM is relatively small but sufficient to drive an important regression of forests and expansion of grasses in ORCHIDEE, in qualitative agreement with pollen data for an HE event. On the contrary, a run with a rapid shift of the AMOC to an hyperactive state of 30 Sv, mimicking the warming phase of a DO event, does not exhibit a strong impact on the European vegetation compared to the glacial control state. For our model, simulating the impact of an HE event thus appears easier than simulating the abrupt transition towards the interstadial phase of a DO.

    For both a collapse or a recovery of the AMOC the vegetation starts to respond to climatic changes immediately but reaches equilibrium about 200 yr after the climate equilibrates, suggesting a possible bias in the climatic reconstructions based on pollen records, which assume equilibrium between climate and vegetation. However, our study does not take into account vegetation feedbacks on the atmosphere.

  20. Two Degrees of Separation: Abrupt Climate Change and the Adverse Impact to US National Security

    Science.gov (United States)

    2009-04-01

    trend of increasing GHG emissions is marginally impacting or irrelevant altogether. “Other factors, including sun spots, solar winds, variations ...climate variations over a wide range of time scales, making it a natural sensor of climate variability and providing a visible expression of climate...many observed changes in phenology and distribution have been associated with rising water temperatures, as well as changes in salinity, oxygen levels

  1. "What Controls the Structure and Stability of the Ocean Meridional Overturning Circulation: Implications for Abrupt Climate Change?"

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, Alexey [Yale University

    2013-11-23

    The central goal of this research project is to understand the properties of the ocean meridional overturning circulation (MOC) – a topic critical for understanding climate variability and stability on a variety of timescales (from decadal to centennial and longer). Specifically, we have explored various factors that control the MOC stability and decadal variability in the Atlantic and the ocean thermal structure in general, including the possibility abrupt climate change. We have also continued efforts on improving the performance of coupled ocean-atmosphere GCMs.

  2. A Generalized Stability Analysis of the AMOC in Earth System Models: Implication for Decadal Variability and Abrupt Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, Alexey V. [Yale Univ., New Haven, CT (United States)

    2015-01-14

    The central goal of this research project was to understand the mechanisms of decadal and multi-decadal variability of the Atlantic Meridional Overturning Circulation (AMOC) as related to climate variability and abrupt climate change within a hierarchy of climate models ranging from realistic ocean models to comprehensive Earth system models. Generalized Stability Analysis, a method that quantifies the transient and asymptotic growth of perturbations in the system, is one of the main approaches used throughout this project. The topics we have explored range from physical mechanisms that control AMOC variability to the factors that determine AMOC predictability in the Earth system models, to the stability and variability of the AMOC in past climates.

  3. A statistical modelling study of the abrupt millennial-scale climate changes focusing on the influence of external forcings

    CERN Document Server

    Mitsui, Takahito

    2015-01-01

    Dansgaard-Oeschger (DO) events are abrupt millennial-scale climate changes mainly detected in the North Atlantic region during the last glacial cycle. The frequency of the DO events varied in time, supposedly because of changes in background climate conditions. Here, we investigate the influences of external forcings on DO events with statistical modelling. We assume two types of generic stochastic dynamical systems models (double-well potential-type and oscillator-type), forced by the northern hemisphere summer insolation change and/or the global ice volume change. The models are calibrated by maximizing their likelihood and compared using the Bayesian Information Criterion (BIC). Among the models, the stochastic oscillator model forced by both insolation and ice volume changes is favored by the NGRIP calcium ion data. The BIC scores provide positive evidence for the ice volume forcing in the presence of the insolation forcing but weak evidence for the insolation forcing in the presence of the ice volume for...

  4. Abrupt Climate Change in the Arctic (and Beyond): An Update (Invited)

    Science.gov (United States)

    Alley, R. B.

    2013-12-01

    Our understanding of future Arctic change is informed by the history of past changes, which often have been both large and abrupt. The well-known ice-age events such as the Younger Dryas show how sea-ice changes can amplify forcing to produce very large responses, with wintertime sea ice especially important. These changes are increasingly seen to have played a central role in the ice-age cycling through their global impact on CO2 storage in the deep ocean. The Heinrich events reveal processes of ice-sheet/ocean interaction, some of which are being played out in Greenland and Antarctica now, and which may have large future effects on sea-level rise. The paleoclimatic record plus physical understanding greatly reduce the worst worries about instabilities from methane stored in cold places, but tend to support a role in amplifying future warming. Overall, the very large impacts of past Arctic changes, and the likelihood that future changes under business-as-usual fossil-fuel emissions will be unprecedented in combined size and speed, raise important questions.

  5. Geomorphic Expression of Abrupt Climate Change in Southwestern North America at the Glacial Termination

    Science.gov (United States)

    Anderson, Roger Y.; Allen, Bruce D.; Menking, Kirsten M.

    2002-05-01

    Eolian and subaqueous landforms composed of gypsum sand provide geomorphic evidence for a wet episode at the termination of glacial climate in southwestern North America. Drying of pluvial Lake Estancia, central New Mexico, occurred after ca. 12,000 14C yr B.P. Thereafter, eolian landforms on the old lake floor, constructed of gypsum sand, were overridden by rising lake water, modified by subaqueous processes, and organized into beach ridges along the lake's eastern shore. Preservation of preexisting eolian landforms in the shallow lake suggests abupt changes in lake level and climate. Available radiocarbon ages suggest that the final highstand recorded by beach ridges may have developed during the Younger Dryas (YD) stade. The beach ridges provide information about lake surface area, which was 45% of the lake area reached during the maximum highstands of the late Pleistocene. A similar proportional response has been reported for YD climate changes outside the North Atlantic region.

  6. A Collaborative Proposal: Simulating and Understanding Abrupt Climate-Ecosystem Changes During Holocene with NCAR-CCSM3.

    Energy Technology Data Exchange (ETDEWEB)

    Zhengyu Liu, Bette Otto-Bliesner

    2013-02-01

    We have made significant progress in our proposed work in the last 4 years (3 years plus 1 year of no cost extension). In anticipation of the next phase of study, we have spent time on the abrupt changes since the last glacial maximum. First, we have performed further model-data comparison based on our baseline TRACE-21 simulation and made important progress towards the understanding of several major climate transitions. Second, we have made a significant effort in processing the model output of TRACE-21 and have put this output on a website for access by the community. Third, we have completed many additional sensitivity experiments. In addition, we have organized synthesis workshops to facilitate and promote transient model-data comparison for the international community. Finally, we have identified new areas of interest for Holocene climate changes.

  7. Quantifying Climate Feedbacks from Abrupt Changes in High-Latitude Trace-Gas Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Schlosser, Courtney Adam [MIT; Walter-Anthony, Katey [University of Alaska; Zhuang, Qianlai [Purdue University; Melillo, Jerry [Marine Biological Laboratory

    2013-04-26

    Our overall goal was to quantify the potential for threshold changes in natural emission rates of trace gases, particularly methane and carbon dioxide, from pan-arctic terrestrial systems under the spectrum of anthropogenically forced climate warming, and the extent to which these emissions provide a strong feedback mechanism to global climate warming. This goal is motivated under the premise that polar amplification of global climate warming will induce widespread thaw and degradation of the permafrost, and would thus cause substantial changes in the extent of wetlands and lakes, especially thermokarst (thaw) lakes, over the Arctic. Through a coordinated effort of field measurements, model development, and numerical experimentation with an integrated assessment model framework, we have investigated the following hypothesis: There exists a climate-warming threshold beyond which permafrost degradation becomes widespread and thus instigates strong and/or sharp increases in methane emissions (via thermokarst lakes and wetland expansion). These would outweigh any increased uptake of carbon (e.g. from peatlands) and would result in a strong, positive feedback to global climate warming.

  8. Thermohaline Circulation and Abrupt Climate Change%温盐环流对气候突变的影响

    Institute of Scientific and Technical Information of China (English)

    闫慧; 李中轩; 陈杰

    2011-01-01

    由于全球气候变暖的一个负反馈机制——温盐环流的存在,使得气候在变暖过程中有可能出现突然变冷事件.地质历史时期气候突变事件的研究表明:这种潜在的突然变冷事件可能会持续几百年甚至上千年.加强对温盐环流强度变化的监测研究对于预测未来的气候变化,制定防灾减灾措施具有重要意义.%The existence of thermohaline circulation, the negative feedback mechanism of global warming, may result in abrupt cold events. Paleoclimate studies indicate that the underlying abrupt cold event may last for hundreds or even thousands of years. To strengthen the monitoring of THC has important significance for predicting climate change and preventing disasters.

  9. Abrupt Climate Change around 4 ka BP:Role of the Thermohaline Circulation as Indicated by a GCM Experiment

    Institute of Scientific and Technical Information of China (English)

    王绍武; 周天军; 蔡静宁; 朱锦红; 谢志辉; 龚道溢

    2004-01-01

    A great deal of palaeoenvironmental and palaeoclimatic evidence suggests that a predominant temperature drop and an aridification occurred at ca. 4.0 ka BP. Palaeoclimate studies in China support this dedution. The collapse of ancient civilizations at ca. 4.0 ka BP in the Nile Valley and Mesopotamia has been attributed to climate-induced aridification. A widespread alternation of the ancient cultures was also found in China at ca. 4.0 ka BP in concert with the collapse of the civilizations in the Old World. Palaeoclimatic studies indicate that the abrupt climate change at 4.0 ka BP is one of the realizations of the cold phase in millennial scale climate oscillations, which may be related to the modulation of the Thermohaline Circulation (THC) over the Atlantic Ocean. Therefore, this study conducts a numerical experiment of a GCM with SST forcing to simulate the impact of the weakening of the THC. Results show a drop in temperature from North Europe, the northern middle East Asia, and northern East Asia and a significant reduction of precipitation in East Africa, the Middle East, the Indian Peninsula, and the Yellow River Valley. This seems to support the idea that coldness and aridification at ca. 4.0 ka BP was caused by the weakening of the THC.

  10. Abrupt climatic changes as triggering mechanisms of massive volcanic collapses: examples from Mexico (Invited)

    Science.gov (United States)

    Capra, L.

    2010-12-01

    Climate changes have been considered to be a triggering mechanism for large magmatic eruptions. However they can also trigger volcanic collapses, phenomena that cause the destruction of the entire sector of a volcano, including its summit. During the past 30 ka, major volcanic collapses occurred just after main glacial peaks that ended with a rapid deglaciation. Glacial debuttressing, load discharge and fluid circulation coupled with the post-glacial increase of humidity and heavy rains can activate the failure of unstable edifices. Looking at the synchronicity of the maximum glaciations during the late Pleistocene and Holocene in the northern and southern hemispheres it is evident that several volcanic collapses are absent during a glacial climax, but start immediately after it during a period of rapid retreat. Several examples can be detected around the world and Mexico is not an exception. The 28 ka Nevado de Toluca volcanic collapse occurred during an intraglacial stage, under humid conditions as evidenced by paleoclimatic studies on lacustrine sediments of the area. The debris avalanche deposit associated to this event clearly shows evidence of a large amount of water into the mass previous to the failure that enhanced its mobility. It also contains peculiar, plastically deformed, m-sized fragment of lacustrine sediments eroded from glacial berms. The 17 ka BP collapse of the Colima Volcano corresponds to the initial stage of glacial retreat in Mexico after the Last Glacial Maximum (22-17.5ka). Also in this case the depositional sequence reflects high humidity conditions with voluminous debris flow containing a large amount logs left by pine trees. The occurrence of cohesive debris flows originating from the failure of a volcanic edifice can also reflect the climatic conditions, indicating important hydrothermal alteration and fluid circulation from ice-melting at an ice-capped volcano, as observed for example at the Pico de Orizaba volcano for the Tetelzingo

  11. Direct North-South synchronization of abrupt climate change record in ice cores using beryllium 10

    Directory of Open Access Journals (Sweden)

    G. M. Raisbeck

    2007-05-01

    Full Text Available A new, decadally resolved record of the 10Be peak at 41 kyr from the EPICA Dome C ice core (Antarctica is used to match it with the same peak in the GRIP ice core (Greenland. This permits a direct synchronisation of the climatic variations around 41 kyr BP, independent of uncertainties related to the ice age-gas age difference in ice cores. Dansgaard-Oeschger event 10 is in the period of best synchronisation and is found to be coeval with an Antarctic temperature maximum. Simulations using a thermal bipolar seesaw model agree reasonably well with the observed relative climate chronology in these two cores. They also reproduce three Antarctic warming events between A1 and A2.

  12. Direct north-south synchronization of abrupt climate change record in ice cores using Beryllium 10

    Directory of Open Access Journals (Sweden)

    G. M. Raisbeck

    2007-09-01

    Full Text Available A new, decadally resolved record of the 10Be peak at 41 kyr from the EPICA Dome C ice core (Antarctica is used to match it with the same peak in the GRIP ice core (Greenland. This permits a direct synchronisation of the climatic variations around this time period, independent of uncertainties related to the ice age-gas age difference in ice cores. Dansgaard-Oeschger event 10 is in the period of best synchronisation and is found to be coeval with an Antarctic temperature maximum. Simulations using a thermal bipolar seesaw model agree reasonably well with the observed relative climate chronology in these two cores. They also reproduce three Antarctic warming events observed between A1 and A2.

  13. Imprint of North-Atlantic abrupt climate changes on western European loess deposits as viewed in a dust emission model

    Science.gov (United States)

    Sima, Adriana; Rousseau, Denis-Didier; Kageyama, Masa; Ramstein, Gilles; Schulz, Michael; Balkanski, Yves; Antoine, Pierre; Dulac, François; Hatté, Christine

    2009-12-01

    Western European loess sequences of the last glaciation (˜100,000-15,000 years BP) exhibit strong, cyclic variations of the sedimentation rate, which are coeval to the Greenland stadial/interstadial cycles and the Heinrich events. These North-Atlantic rapid climate changes appear, thus, as a potential cause for the sedimentation variations, via changes in dust intensity cycle. Here we make a first step in testing this hypothesis, by modelling the impact of the North-Atlantic abrupt climate variations on dust emission. Our dust emission calculations use meteorological fields generated by the LMDZ atmospheric general circulation model at a resolution down to 60 km over Western Europe. Three numerical experiments are run, representing a Greenland stadial, an interstadial and a Heinrich event. Orbital parameters and ice-sheet configuration correspond to conditions from Marine Isotope Stage 3 (˜60,000-25,000 years BP), a period characterized by strong millennial-scale climate variability. The only differences we impose in the boundary conditions regard the North-Atlantic surface temperature and sea-ice cover in the latitudinal band 30°-63°N. The changes in wind, precipitation, soil moisture and snow cover from one simulated state to another result in small differences in dust emission intensity. In contrast, when the inhibition of the aeolian erosion by vegetation is taken into account, the dust fluxes for the cold climate states (Greenland stadial and Heinrich event) become generally more than twice higher than those for the relatively warmer Greenland interstadial, in agreement with the loess data. These results support the hypothesis that the North-Atlantic millennial-scale variability is imprinted in Western European loess profiles, and point to vegetation changes as the main factor responsible for millennial-scale sedimentation variations. An analysis for the English Channel and southern North Sea areas, major potential dust sources, shows that the seasonality

  14. Ecological Regime Shifts in Lake Kälksjön, Sweden, in Response to Abrupt Climate Change Around the 8.2 ka Cooling Event

    DEFF Research Database (Denmark)

    Randsalu-Wendrup, L.; Conley, D.J.; Snowball, I.;

    2012-01-01

    periphytic to planktonic diatom dominance over a 250-year period and a gradual diversification of the periphytic community that spanned c. 150 years. Rapid climate warming following the 8.2 ka event likely caused these changes and both regime shifts are examples of externally driven abrupt ecological change......A detailed diatom record from Lake Ka¨ lksjo¨ n, westcentral Sweden, reveals two periods of abrupt ecological change correlative with the 8.2 ka cooling event. Using a combination of abrupt step changes and piece-wise linear regressions, the diatom data were analyzed for change points over time...... increase in nutrient supply to the lake. The second event was characterized by a substantial shift within the planktonic diatom community from taxa indicative of colder conditions to those indicating warm over 5–10 years at c. 7850 cal. y BP. This event was superimposed on a successive change from...

  15. Do Quercus ilex woodlands undergo abrupt non-linear functional changes in response to human disturbance along a climatic gradient?

    Science.gov (United States)

    Bochet, Esther; García-Fayos, Patricio; José Molina, Maria; Moreno de las Heras, Mariano; Espigares, Tíscar; Nicolau, Jose Manuel; Monleon, Vicente

    2017-04-01

    Theoretical models predict that drylands are particularly prone to suffer critical transitions with abrupt non-linear changes in their structure and functions as a result of the existing complex interactions between climatic fluctuations and human disturbances. However, so far, few studies provide empirical data to validate these models. We aim at determining how holm oak (Quercus ilex) woodlands undergo changes in their functions in response to human disturbance along an aridity gradient (from semi-arid to sub-humid conditions), in eastern Spain. For that purpose, we used (a) remote-sensing estimations of precipitation-use-efficiency (PUE) from enhanced vegetation index (EVI) observations performed in 231x231 m plots of the Moderate Resolution Imaging Spectroradiometer (MODIS); (b) biological and chemical soil parameter determinations (extracellular soil enzyme activity, soil respiration, nutrient cycling processes) from soil sampled in the same plots; (c) vegetation parameter determinations (ratio of functional groups) from vegetation surveys performed in the same plots. We analyzed and compared the shape of the functional change (in terms of PUE and soil and vegetation parameters) in response to human disturbance intensity for our holm oak sites along the aridity gradient. Overall, our results evidenced important differences in the shape of the functional change in response to human disturbance between climatic conditions. Semi-arid areas experienced a more accelerated non-linear decrease with an increasing disturbance intensity than sub-humid ones. The proportion of functional groups (herbaceous vs. woody cover) played a relevant role in the shape of the functional response of the holm oak sites to human disturbance.

  16. Study on the Influence of Abrupt Climate Variation on the Vegetation Based on NDVI

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The research aimed to study the influence of abrupt climate variation on the vegetation based on NDVI. [Method] Based on NDVI and climate data in China during 1982-2000, by using Mann-kendall (MK) abrupt change detection method, the abrupt variations of climate and NDVI were detected. Then, the relationship between two kinds of abrupt variations was discussed. [Result] The large-area abrupt variations of monthly average temperature and rainfall happened in 1983, and the occurrence range in 1999 ...

  17. Abrupt Climate Change. Lessons from Integrated Catastrophic Risk Management. Interim Report

    Energy Technology Data Exchange (ETDEWEB)

    Ermolieva, T.; Obersteiner, M.

    2003-05-06

    This paper is an extended version of the talks 'Uncertainty and Robust Solutions: Lessons from IIASA Case Studies on Catastrophic Risk Management and Economic Growth under Shocks' given on 12 June 2002 and 'Sink Technologies and Climate Risk Management' given on 15 May 2002 at IIASA's Greenhouse Gas Initiative seminars. Risks of disaster arise out of the combination of natural hazards and human activities. We argue that by divorcing the natural disaster issues from social and economic development, half of this disaster equation is ignored. The current pace of disaster development is undermining the markets and safety nets not only of developing countries. Far greater policy coherence is needed between economists, development planners, natural scientists and disaster managers in order to prevent catastrophic losses to human lives, livelihoods, and natural and economic assets. In this paper we present an integrated approach to catastrophic risk management that aims at more coherence and comprehensiveness. The models presented take into account spatial and temporal heterogeneity of catastrophes as well as institutional heterogeneity within a model of economic growth. Loss and gains profiles are functions of various strategies/requirements/goals of agents such as individuals, governments, producers, insurers and investors. GIS-based catastrophe models and stochastic optimization methods allow to guide policy analyses with respect to location specific risk exposures.

  18. Climatic and human impacts on quasi-periodic and abrupt changes of sedimentation rate at multiple time scales in Lake Taihu, China

    Science.gov (United States)

    Liu, Huiyu; Xu, Xiaojuan; Lin, Zhenshan; Zhang, Mingyang; Mi, Ying; Huang, Changchun; Yang, Hao

    2016-12-01

    With the ensemble Empirical Mode Decomposition Method (EEMD) and the non-parametric Mann-Kendall Test, the quasi-periodic and abrupt changes of sedimentation rate at multiple time scales, and their relations to climate changes and human activities from 1951 to 2010 in Meiliang Bay of Lake Taihu (China) were studied. The results showed the following. (1) The change in sedimentation rate can be completely decomposed into three quasi-periodic changes on 3.7, 6.4, and 24-yr time scales, and a long-term trend. (2) The quasi-periodic changes in sedimentation rate are significantly and positively related to changes in annual average temperature at 6.4 and 24-yr time scales and human activities at 3.7-yr time scales, and not significantly related to precipitation at these time scales. The trend of sedimentation rate has a negative relation with temperature, but positive relations with precipitation and human activities. As a whole, the total variance contribution of climate changes to the quasi-periodic changes of sedimentation rate is close to that of human activities; (3) Temperature and precipitation are possibly related to the abrupt change of sedimentation rate as a whole. Floods have significant impacts on abrupt changes in the sedimentation rate at 3.7, 6.4 and 24-yr time scales. Moreover, some abrupt changes of sedimentation rate at 3.7- and 6.4-yr time scales are partly related to the changes of precipitation at 3.1-yr time scale and temperature at 5-yr time scale. The results of this study will help identify the impacts of climate change and human activities on lake sedimentation at different time scales, and will be available for use as a guide for reasonable development and effective protection of lake resources.

  19. New insights on the anatomy of abrupt climate changes based on high-resolution ice core records from NorthGRIP (Greenland)

    Science.gov (United States)

    Capron, E.; Rasmussen, S.; Popp, T. J.; Vaughn, B. H.; Gkinis, V.; Erhardt, T.; Fischer, H.; Blunier, T.; Landais, A.; Pedro, J. B.; Steffensen, J. P.; Svensson, A.; Vinther, B.

    2016-12-01

    The millennial-scale succession of Greenland Stadials (GS) and Greenland Interstadials (GI) illustrates the Greenland expression of the well-known sequence of Dansgaard-Oeschger (DO) events, within which we observe additional climate variations of decadal to centennial-scale duration. Various paradigms, mostly based on interactions between the cryosphere and the ocean, have been proposed to explain the existence and evolution of DO events. Annual to decadal scale records of environmental and climatic regional changes over the rapid transitions are needed to assess whether climate model outputs based on a particular mechanism are consistent with the observed spatial pattern and temporal phasing. Here we present new multiannual resolution stable water isotope measurements (ice δ18O and δD) and annually resolved ion chemistry records from the NorthGRIP ice core. Because these tracers imprint the signatures of different parts of the Northern Hemisphere climate system, we can map the anatomy - the spatial and temporal signature of climate and environmental changes - associated with abrupt transitions (from GS to GI and vice-versa) occurring during Marine Isotopic Stage (MIS) 4. We determine via a statistical approach the timing and duration of the transitions, along with the amplitude of the local and regional changes associated with each Greenland warming and cooling phase. We quantify similarities and differences in the sequences of events through a comparison with results obtained for MIS 3 abrupt transitions and results from the NEEM ice core for selected transitions. The anatomy of abrupt climate changes appears to be different from one event to the next, suggesting that the mechanisms at play are not identical for all of them. We discuss the possible influence of (1) the Heinrich Stadials (i.e. GS during which a Heinrich Event occurred) and of (2) the long term evolution of the climate system on the different decadal to centennial-scale sequences of events

  20. Abrupt Climate Change and the Atlantic Meridional Overturning Circulation: sensitivity and non-linear response to Arctic/sub-Arctic freshwater pulses. Collaborative research. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Christopher [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States)

    2015-06-15

    This project investigated possible mechanisms by which melt-water pulses can induce abrupt change in the Atlantic Meridional Overturning Circulation (AMOC) magnitude. AMOC magnitude is an important ingredient in present day climate. Previous studies have hypothesized abrupt reduction in AMOC magnitude in response to influxes of glacial melt water into the North Atlantic. Notable fresh-water influxes are associated with the terminus of the last ice age. During this period large volumes of melt water accumulated behind retreating ice sheets and subsequently drained rapidly when the ice weakened sufficiently. Rapid draining of glacial lakes into the North Atlantic is a possible origin of a number of paleo-record abrupt climate shifts. These include the Younger-Dryas cooling event and the 8,200 year cooling event. The studies undertaken focused on whether the mechanistic sequence by which glacial melt-water impacts AMOC, which then impacts Northern Hemisphere global mean surface temperature, is dynamically plausible. The work has implications for better understanding past climate stability. The work also has relevance for today’s environment, in which high-latitude ice melting in Greenland appears to be driving fresh water outflows at an accelerating pace.

  1. Application of nonlinear dynamical metho ds in abrupt climate change detection%非线性动力学方法在气候突变检测中的应用∗

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The research of abrupt climate change is an important field in the climate change. The rapid and accurate detection of the abrupt climate change has important practical significance and major economic-social costs, which will help us understand climate change and forecast the future evolutionary trend of the climate system. The detection results of most traditional abrupt climate change depend on the selection of the time scale concerned, which may result in the fact that we cannot identify an abrupt climate change until the event has been past for a long time. Moreover, these detection methods cannot extract the dynamical changes from the observational data of the climate system. As the rapid development in nonlinear science, the abrupt climate change detection technology has also been improved gradually. This article briefly reviews several new progresses in abrupt dynamical detection methods developed on the basis of recent nonlinear technologies, and some applications in the real observational data. These new methods mainly contain the technologies based on the long-range correlation of climate systems, such as moving detrended fluctuation analysis, moving cut data-detrended fluctuation analysis, moving cut data-R/S analysis, degenerate fingerprinting, and red noise. Moreover, some abrupt dynamical detection methods developed by the complexity of the time series, namely, entropy, such as approximate entropy, moving cutting data-approximate entropy, Fisher information, and wavelet Fisher’s information measure. Furthermore, there are some other abrupt dynamical detection methods based on the theory of phase space, such as the dynamics exponent Q. Climate system is a complex dynamical system with nonlinear and interactive nature, which has long-range persistence in spatio-temporal variation, thus the abrupt detection method on spatial field change is pointed out to be a promising direction for further research in future. Because the spatial field contains

  2. Abrupt climate change: Past, present and the search for precursors as an aid to predicting events in the future (Hans Oeschger Medal Lecture)

    Science.gov (United States)

    Mayewski, Paul Andrew

    2016-04-01

    The demonstration using Greenland ice cores that abrupt shifts in climate, Dansgaard-Oeschger (D-O) events, existed during the last glacial period has had a transformational impact on our understanding of climate change in the naturally forced world. The demonstration that D-O events are globally distributed and that they operated during previous glacial periods has led to extensive research into the relative hemispheric timing and causes of these events. The emergence of civilization during our current interglacial, the Holocene, has been attributed to the "relative climate quiescence" of this period relative to the massive, abrupt shifts in climate that characterized glacial periods in the form of D-O events. But, everything is relative and climate change is no exception. The demise of past civilizations, (eg., Mesopatamian, Mayan and Norse) is integrally tied to abrupt climate change (ACC) events operating at regional scales. Regionally to globally distributed ACC events have punctuated the Holocene and extreme events have always posed significant challenges to humans and ecosystems. Current warming of the Arctic, in terms of length of the summer season, is as abrupt and massive, albeit not as extensive, as the transition from the last major D-O event, the Younger Dryas into the Holocene (Mayewski et al., 2013). Tropospheric source greenhouse gas rise and ozone depletion in the stratosphere over Antarctica are triggers for the modern advent of human emission instigated ACCs. Arctic warming and Antarctic ozone depletion have resulted in significance changes to the atmospheric circulation systems that transport heat, moisture, and pollutants in both hemispheres. Climate models offer a critical tool for assessing trends, but they cannot as yet predict ACC events, as evidenced by the inability of these models to predict the rapid onset of Arctic warming and resulting changes in atmospheric circulation; and in the model vs past analog differences in projections for

  3. Abrupt climatic changes on the Tibetan Plateau during the Last Ice Age——Comparative study of the Guliya ice core with the Greenland GRIP ice core

    Institute of Scientific and Technical Information of China (English)

    姚檀栋

    1999-01-01

    Based on a comparative study of the Gtdiya ice core with the Greenland GRIP ice core, the abrupt climatic changes on the Tibetan Plateau during the Last Ice Age have been examined. The major stadial-interstadial events and 7 warm events (BrΦrump, Odderade, Oerel, Glinde, Hengelo, Denekamp, BΦlling) are consistent in the two ice cores. However, there are some unique features in the Guliya ice core records. The transition from warm to cold periods in the Guliya ice core is faster than that in the Greenland GRIP ice core. The magnitude of the climatic changes in the Guliya ice core is also larger than that in the Greenland GRIP ice core. Another significant feature of the Guliya ice core records is that there is a series of cycles of about 200 a from 18 to 35 kaBP. 22 warm events and 20 cold events with a fluctuation magnitude of 7℃ have been distinguished. The warm and cold events with a fluctuation magnitude within 3℃ are as high as 100. It is speculated that the abrupt climatic changes in different

  4. The Abrupt Climatic Changes During the Last Deglaciation: Direct Land-sea Correlation From a Marine Pollen Record off Southeastern United States

    Science.gov (United States)

    Desprat, S.; McManus, J. F.; Peteet, D.

    2007-12-01

    We present a new direct land-sea correlation covering the last deglaciation in order a) to provide a better documentation of the regional vegetation changes in southeastern North America and b) more particularly to assess the connection of the continental climatic changes to North Atlantic circulation rapid variability. It was achieved using coupled analyses of pollen and marine climatic proxies from core KNR140-GGC39 (Blake Outer Ridge) at very high time-resolution. Mg/Ca ratio, planktonic δ18O, mean "sortable silt" grain size (mean S¯S¯) were analyzed in order to get records of SST, salinity and bottom current strength at the core site (Evans et al., submitted to Paleoceanography). The abrupt climatic changes which characterize the last deglaciation, in particular the major cold oscillations Heinrich event 1 (H1) and Younger Dryas (YD), have been widely documented in the North Atlantic and adjacent continents. However, in the tropical and subtropical North Atlantic and southeastern United States, the climatic signature of these events appears quite different and somehow unclear. Our direct land-sea correlation shows three configurations: 1- H1 period: cold climatic conditions in southeastern US (high percentages of boreal and herbaceous taxa) but only extremely cold at around 17 ka, accumulation of salty water in the subtropics (high δ18OSW- IVC) and weak bottom current intensity at the site (low mean S¯S¯) 2- Bolling Alleröd interval: abrupt warming in southeastern US (decrease of boreal taxa in favour of Quercus) at the beginning, synchronous to northern export of the salty water previously accumulated and to an increase of the bottom current strength at the site 3- YD period: mild and wet conditions in southeastern US (expansion of Tsuga and Quercus), decrease of the bottom current strength at the site and accumulation of salty water in the subtropical regions but less than during H1.

  5. The ACER pollen and charcoal database: a global resource to document vegetation and fire response to abrupt climate changes during the last glacial period

    Science.gov (United States)

    Sánchez Goñi, María Fernanda; Desprat, Stéphanie; Daniau, Anne-Laure; Bassinot, Frank C.; Polanco-Martínez, Josué M.; Harrison, Sandy P.; Allen, Judy R. M.; Anderson, R. Scott; Behling, Hermann; Bonnefille, Raymonde; Burjachs, Francesc; Carrión, José S.; Cheddadi, Rachid; Clark, James S.; Combourieu-Nebout, Nathalie; Mustaphi, Colin. J. Courtney; Debusk, Georg H.; Dupont, Lydie M.; Finch, Jemma M.; Fletcher, William J.; Giardini, Marco; González, Catalina; Gosling, William D.; Grigg, Laurie D.; Grimm, Eric C.; Hayashi, Ryoma; Helmens, Karin; Heusser, Linda E.; Hill, Trevor; Hope, Geoffrey; Huntley, Brian; Igarashi, Yaeko; Irino, Tomohisa; Jacobs, Bonnie; Jiménez-Moreno, Gonzalo; Kawai, Sayuri; Kershaw, A. Peter; Kumon, Fujio; Lawson, Ian T.; Ledru, Marie-Pierre; Lézine, Anne-Marie; Liew, Ping Mei; Magri, Donatella; Marchant, Robert; Margari, Vasiliki; Mayle, Francis E.; Merna McKenzie, G.; Moss, Patrick; Müller, Stefanie; Müller, Ulrich C.; Naughton, Filipa; Newnham, Rewi M.; Oba, Tadamichi; Pérez-Obiol, Ramón; Pini, Roberta; Ravazzi, Cesare; Roucoux, Katy H.; Rucina, Stephen M.; Scott, Louis; Takahara, Hikaru; Tzedakis, Polichronis C.; Urrego, Dunia H.; van Geel, Bas; Valencia, B. Guido; Vandergoes, Marcus J.; Vincens, Annie; Whitlock, Cathy L.; Willard, Debra A.; Yamamoto, Masanobu

    2017-09-01

    Quaternary records provide an opportunity to examine the nature of the vegetation and fire responses to rapid past climate changes comparable in velocity and magnitude to those expected in the 21st-century. The best documented examples of rapid climate change in the past are the warming events associated with the Dansgaard-Oeschger (D-O) cycles during the last glacial period, which were sufficiently large to have had a potential feedback through changes in albedo and greenhouse gas emissions on climate. Previous reconstructions of vegetation and fire changes during the D-O cycles used independently constructed age models, making it difficult to compare the changes between different sites and regions. Here, we present the ACER (Abrupt Climate Changes and Environmental Responses) global database, which includes 93 pollen records from the last glacial period (73-15 ka) with a temporal resolution better than 1000 years, 32 of which also provide charcoal records. A harmonized and consistent chronology based on radiometric dating (14C, 234U/230Th, optically stimulated luminescence (OSL), 40Ar/39Ar-dated tephra layers) has been constructed for 86 of these records, although in some cases additional information was derived using common control points based on event stratigraphy. The ACER database compiles metadata including geospatial and dating information, pollen and charcoal counts, and pollen percentages of the characteristic biomes and is archived in Microsoft AccessTM at https://doi.org/10.1594/PANGAEA.870867.

  6. Work More? The 8.2 kaBP Abrupt Climate Change Event and the Origins of Irrigation Agriculture and Surplus Agro-Production in Mesopotamia

    Science.gov (United States)

    Weiss, H.

    2003-12-01

    The West Asian archaeological record is of sufficient transparency and resolution to permit observation of the social responses to the major Holocene abrupt climate change events at 8.2, 5.2 and 4.2 kaBP. The 8.2kaBP abrupt climate change event in West Asia was a three hundred year aridification and cooling episode. During this period rain-fed agriculture, established for over a millennium in northern Mesopotamia, suddenly collapsed. Irrigation agriculture, pastoral nomadism, or migration were the only subsistence alternatives for populations previously supported by cereal dry-farming. Irrigation agriculture was not, however, possible along the northern alluvial plains of the Tigris and Euphrates Rivers, where incised riverbeds were several meters below plain level. Exploitable plain-level levees were only accessible in southern-most alluvial plain, at the head of the present-day Persian Gulf. The archaeological data from this region documents the first irrigation agriculture settlement of the plain during the 8.2 kaBP event. Irrigation agriculture provides about twice the yield of dry-farming in Mesopotamia, but at considerable labor costs relative to dry-farming. With irrigation agriculture surplus production was now available for deployment. But why work more? The 8.2 kaBP event provided the natural force for Mesopotamian irrigation agriculture and surplus production that were essential for the earliest class-formation and urban life.

  7. The fluvial system response to abrupt climate change during the last cold stage: the Upper Pleistocene River Thames fluvial succession at Ashton Keynes, UK

    Science.gov (United States)

    Lewis, S. G.; Maddy, D.; Scaife, R. G.

    2001-02-01

    The last interglacial-glacial cycle (125-10 ka BP) is characterised by numerous rapid shifts in global climate on sub-Milankovitch timescales, recorded in the ocean and ice core records. These climatic fluctuations are clearly recorded in those European terrestrial sedimentary sequences that span this time period without interruption. In the UK, only fragmentary Upper Pleistocene sequences exist, mainly within the fluvial archive of the major river systems such as the Thames. The response of the upper River Thames to abrupt fluctuations in climate is documented in the fluvial sediments beneath the Floodplain Terrace (Northmoor Member of the Upper Thames Formation) at Ashton Keynes, Wiltshire. A number of criteria are set out by which significant changes in the fluvial system may be established from the sedimentological, palaeoecological and geochronological information contained within the succession. The sedimentary succession is divisible into four facies associations, on the basis of their sedimentology and bounding surface characteristics. These represent distinct phases of fluvial activity at the site and allow changes in fluvial style to be inferred. Palaeoecological reconstructions from pollen analysis of peats within the sequence provides an indication of the nature and direction of Late Glacial environmental change and optically stimulated luminescence and radiocarbon dating methods provide chronological control on the sequence. These data suggest that major changes in fluvial style are recorded within the succession, which can be related to the climatic fluctuations that took place on the oxygen isotope stage 5a/4 transition (approximately 70 ka BP) and the Devensian Late Glacial climatic warm-cold-warm oscillation (13-11 ka BP). The changes in fluvial style are a result of variations in sediment supply to the river resulting from changes in slope stability, vegetation cover and cold-climate mass movement processes and variations in discharge regime

  8. Synchronous volcanic eruptions and abrupt climate change ∼17.7 ka plausibly linked by stratospheric ozone depletion.

    Science.gov (United States)

    McConnell, Joseph R; Burke, Andrea; Dunbar, Nelia W; Köhler, Peter; Thomas, Jennie L; Arienzo, Monica M; Chellman, Nathan J; Maselli, Olivia J; Sigl, Michael; Adkins, Jess F; Baggenstos, Daniel; Burkhart, John F; Brook, Edward J; Buizert, Christo; Cole-Dai, Jihong; Fudge, T J; Knorr, Gregor; Graf, Hans-F; Grieman, Mackenzie M; Iverson, Nels; McGwire, Kenneth C; Mulvaney, Robert; Paris, Guillaume; Rhodes, Rachael H; Saltzman, Eric S; Severinghaus, Jeffrey P; Steffensen, Jørgen Peder; Taylor, Kendrick C; Winckler, Gisela

    2017-09-05

    Glacial-state greenhouse gas concentrations and Southern Hemisphere climate conditions persisted until ∼17.7 ka, when a nearly synchronous acceleration in deglaciation was recorded in paleoclimate proxies in large parts of the Southern Hemisphere, with many changes ascribed to a sudden poleward shift in the Southern Hemisphere westerlies and subsequent climate impacts. We used high-resolution chemical measurements in the West Antarctic Ice Sheet Divide, Byrd, and other ice cores to document a unique, ∼192-y series of halogen-rich volcanic eruptions exactly at the start of accelerated deglaciation, with tephra identifying the nearby Mount Takahe volcano as the source. Extensive fallout from these massive eruptions has been found >2,800 km from Mount Takahe. Sulfur isotope anomalies and marked decreases in ice core bromine consistent with increased surface UV radiation indicate that the eruptions led to stratospheric ozone depletion. Rather than a highly improbable coincidence, circulation and climate changes extending from the Antarctic Peninsula to the subtropics-similar to those associated with modern stratospheric ozone depletion over Antarctica-plausibly link the Mount Takahe eruptions to the onset of accelerated Southern Hemisphere deglaciation ∼17.7 ka.

  9. Synchronous volcanic eruptions and abrupt climate change ˜17.7 ka plausibly linked by stratospheric ozone depletion

    Science.gov (United States)

    McConnell, Joseph R.; Burke, Andrea; Dunbar, Nelia W.; Köhler, Peter; Thomas, Jennie L.; Arienzo, Monica M.; Chellman, Nathan J.; Maselli, Olivia J.; Sigl, Michael; Adkins, Jess F.; Baggenstos, Daniel; Burkhart, John F.; Brook, Edward J.; Buizert, Christo; Cole-Dai, Jihong; Fudge, T. J.; Knorr, Gregor; Graf, Hans-F.; Grieman, Mackenzie M.; Iverson, Nels; McGwire, Kenneth C.; Mulvaney, Robert; Paris, Guillaume; Rhodes, Rachael H.; Saltzman, Eric S.; Severinghaus, Jeffrey P.; Steffensen, Jørgen Peder; Taylor, Kendrick C.; Winckler, Gisela

    2017-09-01

    Glacial-state greenhouse gas concentrations and Southern Hemisphere climate conditions persisted until ˜17.7 ka, when a nearly synchronous acceleration in deglaciation was recorded in paleoclimate proxies in large parts of the Southern Hemisphere, with many changes ascribed to a sudden poleward shift in the Southern Hemisphere westerlies and subsequent climate impacts. We used high-resolution chemical measurements in the West Antarctic Ice Sheet Divide, Byrd, and other ice cores to document a unique, ˜192-y series of halogen-rich volcanic eruptions exactly at the start of accelerated deglaciation, with tephra identifying the nearby Mount Takahe volcano as the source. Extensive fallout from these massive eruptions has been found >2,800 km from Mount Takahe. Sulfur isotope anomalies and marked decreases in ice core bromine consistent with increased surface UV radiation indicate that the eruptions led to stratospheric ozone depletion. Rather than a highly improbable coincidence, circulation and climate changes extending from the Antarctic Peninsula to the subtropics—similar to those associated with modern stratospheric ozone depletion over Antarctica—plausibly link the Mount Takahe eruptions to the onset of accelerated Southern Hemisphere deglaciation ˜17.7 ka.

  10. The ACER pollen and charcoal database: a global resource to document vegetation and fire response to abrupt climate changes during the last glacial period

    Directory of Open Access Journals (Sweden)

    M. F. Sánchez Goñi

    2017-09-01

    Full Text Available Quaternary records provide an opportunity to examine the nature of the vegetation and fire responses to rapid past climate changes comparable in velocity and magnitude to those expected in the 21st-century. The best documented examples of rapid climate change in the past are the warming events associated with the Dansgaard–Oeschger (D–O cycles during the last glacial period, which were sufficiently large to have had a potential feedback through changes in albedo and greenhouse gas emissions on climate. Previous reconstructions of vegetation and fire changes during the D–O cycles used independently constructed age models, making it difficult to compare the changes between different sites and regions. Here, we present the ACER (Abrupt Climate Changes and Environmental Responses global database, which includes 93 pollen records from the last glacial period (73–15 ka with a temporal resolution better than 1000 years, 32 of which also provide charcoal records. A harmonized and consistent chronology based on radiometric dating (14C, 234U∕230Th, optically stimulated luminescence (OSL, 40Ar∕39Ar-dated tephra layers has been constructed for 86 of these records, although in some cases additional information was derived using common control points based on event stratigraphy. The ACER database compiles metadata including geospatial and dating information, pollen and charcoal counts, and pollen percentages of the characteristic biomes and is archived in Microsoft AccessTM at https://doi.org/10.1594/PANGAEA.870867.

  11. The complex behavior of the Cordilleran Ice Sheet and mountain glaciers to abrupt climate change during the latest Pleistocene

    Science.gov (United States)

    Menounos, Brian; Goehring, Brent; Osborn, Gerald; Clarke, Garry K. C.; Ward, Brent; Margold, Martin; Bond, Jeff; Clague, John J.; Lakeman, Tom; Schaefer, Joerg; Koch, Joe; Gosse, John; Stroeven, Arjen P.; Seguinot, Julien; Heyman, Jakob; Fulton, Robert

    2014-05-01

    Surficial mapping and more than 70 radiometric ages 10Be, 14C] constrain the evolution of the Cordilleran Ice Sheet (CIS) and associated mountain glaciers in western Canada during the latest Pleistocene. Our data suggest that: i) there is widespread evidence for the Younger Dryas (YD) throughout the mountains of western Canada; ii) late Pleistocene climate reconstructions based solely on alpine moraines may be misleading in regions with decaying ice sheets; iii) extensive interfluves in some mountain regions were ice-free between 16 ka and 13 ka (kilo calibrated yrs BP). Initial decay of the CIS from its maximum extent around 16 ka was likely due to a combination of climatic (surface melting) and dynamical factors. Climate amelioration during the Bølling-Allerød Warm Period [14.7-12.9 ka], likely the cause for the major phase of CIS decay, resulted in ice sheet equilibrium line altitudes (ELAs) ranging from 2500 m asl in southern BC to around 2000 m asl along the BC-Yukon border. Hence, before the onset of the Younger Dryas (YD) Cold Period [12.9-11.7 ka], the ice sheet shrank and became a labyrinth of individual and coalescing valley glaciers fed by major accumulation zones centered on the Coast Mountains and other high ranges of NW Canada. The response of remnant ice and cirque glaciers to the YD climate deterioration was highly variable. In some cases, small glaciers (0.5-2 km2) built YD moraines that were only hundreds of meters beyond those constructed during the Little Ice Age (LIA) [0.30-0.15 ka]. Our dating also reveals that much larger glaciers persisted in nearby valleys that lie hundreds of meters below the cirques. Hence, we infer that many cirques were completely deglaciated prior the YD, in contrast to low-lying valleys where ice sheet remnants persisted. Glaciers also advanced in north-central British Columbia during the YD, but here glaciers constructed large terminal and lateral moraines. In the Cassiar and northern Coast mountains, for example

  12. Abrupt climate change of East Asian Monsoon at 130 kaBP inferred from a high resolution stalagmite δ18O record

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiuyang; WANG Yongjin; KONG Xinggong; WU Jiangying; SHAO Xiaohua; XIA Zhifeng; CHENG Hai

    2005-01-01

    230Th ages and oxygen isotope data of a stalagmite from Shanbao Cave in Hubei Province characterize the East Asian Monsoon precipitation from 133 to127 ka. The decadal-scale high-resolution δ18O record reveals a detailed transitional process from the Penultimate Glaciation to the Last Interglaciation. As established with 230Th dates, the age of the Termination II is determined to be 129.5±1.0 kaBP, which supports the Northern Hemisphere insolation as the triggers for the ice-age cycles. In our δ18O record, the glacial/ interglacial fluctuation reaches about 4‰, almost the same level as in other Asian Monsoon cave stalagmite δ18O records. The transition of the glacial/interglacial period in our record can be recognized as four stepwise stages, among which, a rapid rise of monsoon precipitation follows the stage of "Termination II pause". The rapid rise is synchronous with the abrupt change of global methane concentration, which reflects that an increase in both Asian Monsoon precipitation and tropical wetland plays an important role in the global climate changes.

  13. Abrupt climate shift in the Western Mediterranean Sea

    Science.gov (United States)

    Schroeder, K.; Chiggiato, J.; Bryden, H. L.; Borghini, M.; Ben Ismail, S.

    2016-03-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected.

  14. Modeling Past Abrupt Climate Changes

    DEFF Research Database (Denmark)

    Marchionne, Arianna

    According to Milankovitch theory of ice ages, glacial cycles are driven by variations in the insolation, i.e. the amount of the incoming solar radiation reaching the Earth. These variations are associated with variations of the Earth's orbit. Many attempts have been made to identify the in uence...

  15. Detecting abrupt dynamic change based on changes in the fractal properties of spatial images

    Science.gov (United States)

    Liu, Qunqun; He, Wenping; Gu, Bin; Jiang, Yundi

    2016-08-01

    Many abrupt climate change events often cannot be detected timely by conventional abrupt detection methods until a few years after these events have occurred. The reason for this lag in detection is that abundant and long-term observational data are required for accurate abrupt change detection by these methods, especially for the detection of a regime shift. So, these methods cannot help us understand and forecast the evolution of the climate system in a timely manner. Obviously, spatial images, generated by a coupled spatiotemporal dynamical model, contain more information about a dynamic system than a single time series, and we find that spatial images show the fractal properties. The fractal properties of spatial images can be quantitatively characterized by the Hurst exponent, which can be estimated by two-dimensional detrended fluctuation analysis (TD-DFA). Based on this, TD-DFA is used to detect an abrupt dynamic change of a coupled spatiotemporal model. The results show that the TD-DFA method can effectively detect abrupt parameter changes in the coupled model by monitoring the changing in the fractal properties of spatial images. The present method provides a new way for abrupt dynamic change detection, which can achieve timely and efficient abrupt change detection results.

  16. 近60a来玛纳斯河流域气候变化趋势及突变分析%Analysis of the Climate Change and Abrupt Change in the Manas River Drainage Basin in Recent 60 Years

    Institute of Scientific and Technical Information of China (English)

    王东方; 任刚; 张凤华

    2011-01-01

    [ Objective and Method ] Global climate change is the gravest environmental problem that human has ever faced. The climate change in China is similar to global change but is most significant in its arid land. Xinjiang is among the most eminent arid region. In this study, the Manas River Valley, which is the typical inland river formed from glacier - melted water in the Central Asia, was chosen as the sample. The temperature and precipitation change trend from 1956 to 2010 were analyzed by using linear regression analysis and Man - Kendall trend text. [ Result ] The results show the mean climate generally trended to be warm and humid in recent 60 years, and the rate of increase were 0. 44℃ /10 a and 12. 6 mm/10a; The temperature trend rates of spring, summer, autumn and winter respectively were 0.50℃/10 a, 0. 21℃/10 a, 0.52℃/10 a, 0.52℃/10 a, and the precipitation trend rate were 2.44 mm/10 a, 3.22 mm/10 a, 2.76 mm/10 a, 3.64 mm/10 a. The mean annual temperature of the Basin revealed a obvious increasing trend in 1980s. The point of abrupt change was in 1989, and the difference seasonal abrupt change of annual average temperature occurred in 1995, 1986, 1996 and 1987, respectively. The annual precipitation abrupt change also occurred in the late 1980s, and the points of abrupt change in autumn and winter occurred increased at 1983 and 1997, but there were not abrupt changes in spring and summer. [ Conclusion ] The findings are meaningful for us to have a comprehensive understanding of the climate change to predict the annual and seasonal climate change in the arid land.%[目的]气候变化是21世纪人类面临的最大环境问题之一.其中以干旱区较为明显,而新疆是最为突出的地区之一.[方法]以中亚典型冰川融化区玛纳斯河流域为例,运用线性回归及Mann - Kendall趋势检验方法分析其1956 ~2010年气温及降水资料的变化趋势和突变点.[结果]近60a来玛纳斯河流域经历了一个增温趋

  17. The slowdown of the North Atlantic Gulf stream: an economic perspective on adaptation. In: What if... abrupt and extreme climage change?

    NARCIS (Netherlands)

    Ierland, van E.C.

    2008-01-01

    This NWO publication consists the following contributions: Exploring governmental and victim responsibilities in view of abrupt climate change in North-Western Europe; Coping with Extreme Events: Institutional Flocking; Abrupt climate change: Analogies in impacts and coping mechanisms; Catching a

  18. A simple conceptual model of abrupt glacial climate events

    CERN Document Server

    Braun, H; Christl, M; Chialvo, D R

    2008-01-01

    Here we use a very simple conceptual model in an attempt to reduce essential parts of the complex nonlinearity of abrupt glacial climate changes (the so-called Dansgaard-Oeschger events) to a few simple principles, namely (i) a threshold process, (ii) an overshooting in the stability of the system and (iii) a millennial-scale relaxation. By comparison with a so-called Earth system model of intermediate complexity (CLIMBER-2), in which the events represent oscillations between two climate states corresponding to two fundamentally different modes of deep-water formation in the North Atlantic, we demonstrate that the conceptual model captures fundamental aspects of the nonlinearity of the events in that model. We use the conceptual model in order to reproduce and reanalyse nonlinear resonance mechanisms that were already suggested in order to explain the characteristic time scale of Dansgaard-Oeschger events. In doing so we identify a new form of stochastic resonance (i.e. an overshooting stochastic resonance) a...

  19. Gradual onset and recovery of the Younger Dryas abrupt climate event in the tropics.

    Science.gov (United States)

    Partin, J W; Quinn, T M; Shen, C-C; Okumura, Y; Cardenas, M B; Siringan, F P; Banner, J L; Lin, K; Hu, H-M; Taylor, F W

    2015-01-01

    Proxy records of temperature from the Atlantic clearly show that the Younger Dryas was an abrupt climate change event during the last deglaciation, but records of hydroclimate are underutilized in defining the event. Here we combine a new hydroclimate record from Palawan, Philippines, in the tropical Pacific, with previously published records to highlight a difference between hydroclimate and temperature responses to the Younger Dryas. Although the onset and termination are synchronous across the records, tropical hydroclimate changes are more gradual (>100 years) than the abrupt (10-100 years) temperature changes in the northern Atlantic Ocean. The abrupt recovery of Greenland temperatures likely reflects changes in regional sea ice extent. Proxy data and transient climate model simulations support the hypothesis that freshwater forced a reduction in the Atlantic meridional overturning circulation, thereby causing the Younger Dryas. However, changes in ocean overturning may not produce the same effects globally as in Greenland.

  20. Neanderthal and Anatomically Modern Human interaction with Abrupt Late Pleistocene Environments - the data is finally good enough to talk about climate change!

    Science.gov (United States)

    Blockley, Simon; Schreve, Danielle

    2015-04-01

    The timing and nature of the appearance of Anatomically Modern Humans (AMH) in Europe, their interaction with, and eventual morphological replacement of Neanderthals (despite some shared genetic heritage) has been a matter of intense debate within archaeology for a generation. This period, often termed the Middle to Upper Palaeolithic transition occurs in the latter part of Marine Isotope Stage Three and in recent decades archaeological interest has been complemented by the input of palaeoclimate scientists, over the role of abrupt climate change in this process. This was due to the recognition from ice core and marine proxy archives, in particular, of periods if intense cooling, correlated to the marine record of Heinrich ice rafted debris layers from the Atlantic. As a result of these collaborations between the archaeological and palaeoenvironmental communities various drivers have been proposed for the Middle to Upper Palaeolithic Transition that include: (1) resource competition between two species occupying similar niches; (2) the impact of repeated cycles of Heinrich event cooling, leading to the decline and eventual disappearance of the Neanderthal populations, leaving a new region open for AMH exploitation; and (3) catastrophic impacts of large volcanic eruptions on Neanderthal populations. Attempts to address the above hypotheses have been dogged by the chronological precision available for a number of key archives. The accuracy of many of the radiocarbon ages that underpin the chronology for both Neanderthal and AMH archaeological sites has been questioned1. This has been exacerbated by uncertainties over the influence of variability in the radiocarbon marine reservoir effect on marine palaeoclimate records and a marine dominated radiocarbon calibration curve. Additionally, the counting uncertainties of the master Greenland palaeoclimate archives are also large by this time, meaning palaeoclimate interpretation can be equivocal. However, several research

  1. Detection of Abrupt Changes in Dynamic Systems,

    Science.gov (United States)

    1984-01-01

    the detection of abrupt chnages in dynamic systems. These efforts have been motivated by a wide variety of applications includinq the detection of...34Failure Detection in Dynimic Systems," AGARD Lecture Series No. 109 on Fault Tolerance Design and Redundancy Management Technqiues, Athens, Rome, and

  2. Causes and projections of abrupt climate-driven ecosystem shifts in the North Atlantic

    DEFF Research Database (Denmark)

    Beaugrand, G.; Edwards, M.; Brander, Keith

    2008-01-01

    Warming of the global climate is now unequivocal and its impact on Earth' functional units has become more apparent. Here, we show that marine ecosystems are not equally sensitive to climate change and reveal a critical thermal boundary where a small increase in temperature triggers abrupt...... ecosystem shifts seen across multiple trophic levels. This large-scale boundary is located in regions where abrupt ecosystem shifts have been reported in the North Atlantic sector and thereby allows us to link these shifts by a global common phenomenon. We show that these changes alter the biodiversity...... and carrying capacity of ecosystems and may, combined with fishing, precipitate the reduction of some stocks of Atlantic cod already severely impacted by exploitation. These findings offer a way to anticipate major ecosystem changes and to propose adaptive strategies for marine exploited resources such as cod...

  3. Abrupt cooling over the North Atlantic in modern climate models

    Science.gov (United States)

    Sgubin, Giovanni; Swingedouw, Didier; Drijfhout, Sybren; Mary, Yannick; Bennabi, Amine

    2017-02-01

    Observations over the 20th century evidence no long-term warming in the subpolar North Atlantic (SPG). This region even experienced a rapid cooling around 1970, raising a debate over its potential reoccurrence. Here we assess the risk of future abrupt SPG cooling in 40 climate models from the fifth Coupled Model Intercomparison Project (CMIP5). Contrary to the long-term SPG warming trend evidenced by most of the models, 17.5% of the models (7/40) project a rapid SPG cooling, consistent with a collapse of the local deep-ocean convection. Uncertainty in projections is associated with the models' varying capability in simulating the present-day SPG stratification, whose realistic reproduction appears a necessary condition for the onset of a convection collapse. This event occurs in 45.5% of the 11 models best able to simulate the observed SPG stratification. Thus, due to systematic model biases, the CMIP5 ensemble as a whole underestimates the chance of future abrupt SPG cooling, entailing crucial implications for observation and adaptation policy.

  4. A stratigraphic framework for naming and robust correlation of abrupt climatic changes during the last glacial period based on three synchronized Greenland ice core records

    Science.gov (United States)

    Rasmussen, Sune O.

    2014-05-01

    Due to their outstanding resolution and well-constrained chronologies, Greenland ice core records have long been used as a master record of past climatic changes during the last interglacial-glacial cycle in the North Atlantic region. As part of the INTIMATE (INtegration of Ice-core, MArine and TErrestrial records) project, protocols have been proposed to ensure consistent and robust correlation between different records of past climate. A key element of these protocols has been the formal definition of numbered Greenland Stadials (GS) and Greenland Interstadials (GI) within the past glacial period as the Greenland expressions of the characteristic Dansgaard-Oeschger events that represent cold and warm phases of the North Atlantic region, respectively. Using a recent synchronization of the NGRIP, GRIP, and GISP2 ice cores that allows the parallel analysis of all three records on a common time scale, we here present an extension of the GS/GI stratigraphic template to the entire glacial period. This is based on a combination of isotope ratios (δ18O, reflecting mainly local temperature) and calcium concentrations (reflecting mainly atmospheric dust loading). In addition to the well-known sequence of Dansgaard-Oeschger events that were first defined and numbered in the ice core records more than two decades ago, a number of short-lived climatic oscillations have been identified in the three synchronized records. Some of these events have been observed in other studies, but we here propose a consistent scheme for discriminating and naming all the significant climatic events of the last glacial period that are represented in the Greenland ice cores. This is a key step aimed at promoting unambiguous comparison and correlation between different proxy records, as well as a more secure basis for investigating the dynamics and fundamental causes of these climatic perturbations. The work presented is under review for publication in Quaternary Science Reviews. Author team: S

  5. Paleoclimate. Synchronization of North Pacific and Greenland climates preceded abrupt deglacial warming.

    Science.gov (United States)

    Praetorius, Summer K; Mix, Alan C

    2014-07-25

    Some proposed mechanisms for transmission of major climate change events between the North Pacific and North Atlantic predict opposing patterns of variations; others suggest synchronization. Resolving this conflict has implications for regulation of poleward heat transport and global climate change. New multidecadal-resolution foraminiferal oxygen isotope records from the Gulf of Alaska (GOA) reveal sudden shifts between intervals of synchroneity and asynchroneity with the North Greenland Ice Core Project (NGRIP) δ(18)O record over the past 18,000 years. Synchronization of these regions occurred 15,500 to 11,000 years ago, just prior to and throughout the most abrupt climate transitions of the last 20,000 years, suggesting that dynamic coupling of North Pacific and North Atlantic climates may lead to critical transitions in Earth's climate system.

  6. Characteristics of the deep ocean carbon system during the past 150,000 years: SigmaCO2 distributions, deep water flow patterns, and abrupt climate change.

    Science.gov (United States)

    Boyle, E A

    1997-08-05

    Studies of carbon isotopes and cadmium in bottom-dwelling foraminifera from ocean sediment cores have advanced our knowledge of ocean chemical distributions during the late Pleistocene. Last Glacial Maximum data are consistent with a persistent high-SigmaCO2 state for eastern Pacific deep water. Both tracers indicate that the mid-depth North and tropical Atlantic Ocean almost always has lower SigmaCO2 levels than those in the Pacific. Upper waters of the Last Glacial Maximum Atlantic are more SigmaCO2-depleted and deep waters are SigmaCO2-enriched compared with the waters of the present. In the northern Indian Ocean, delta13C and Cd data are consistent with upper water SigmaCO2 depletion relative to the present. There is no evident proximate source of this SigmaCO2-depleted water, so I suggest that SigmaCO2-depleted North Atlantic intermediate/deep water turns northward around the southern tip of Africa and moves toward the equator as a western boundary current. At long periods (>15,000 years), Milankovitch cycle variability is evident in paleochemical time series. But rapid millennial-scale variability can be seen in cores from high accumulation rate series. Atlantic deep water chemical properties are seen to change in as little as a few hundred years or less. An extraordinary new 52.7-m-long core from the Bermuda Rise contains a faithful record of climate variability with century-scale resolution. Sediment composition can be linked in detail with the isotope stage 3 interstadials recorded in Greenland ice cores. This new record shows at least 12 major climate fluctuations within marine isotope stage 5 (about 70,000-130,000 years before the present).

  7. Gradual and abrupt changes during the Mid-Pleistocene Transition

    Science.gov (United States)

    Ford, Heather L.; Sosdian, Sindia M.; Rosenthal, Yair; Raymo, Maureen E.

    2016-09-01

    During the Mid-Pleistocene Transition (MPT), the dominant glacial-interglacial cyclicity as inferred from the marine δ18O records of benthic foraminifera (δ18Obenthic) changed from 41 kyr to 100 kyr years in the absence of a comparable change in orbital forcing. Currently, only two Mg/Ca-derived, high-resolution bottom water temperature (BWT) records exist that can be used with δ18Obenthic records to separate temperature and ice volume signals over the Pleistocene. However, these two BWT records suggest a different pattern of climate change occurred over the MPT-a record from North Atlantic DSDP Site 607 suggests BWT decreased with no long-term trend in ice volume over the MPT, while South Pacific ODP Site 1123 suggests that BWT has been relatively stable over the last 1.5 Myr but that there was an abrupt increase in ice volume at ∼900 kyr. In this paper we attempt to reconcile these two views of climate change across the MPT. Specifically, we investigated the suggestion that the secular BWT trend obtained from Mg/Ca measurements on Cibicidoides wuellerstorfi and Oridorsalis umbonatus species from N. Atlantic Site 607 is biased by the possible influence of Δ[CO32-] on Mg/Ca values in these species by generating a low-resolution BWT record using Uvigerina spp., a genus whose Mg/Ca values are not thought to be influenced by Δ[CO32-]. We find a long-term BWT cooling of ∼2-3°C occurred from 1500 to ∼500 kyr in the N. Atlantic, consistent with the previously generated C. wuellerstorfi and O. umbonatus BWT record. We also find that changes in ocean circulation likely influenced δ18Obenthic, BWT, and δ18Oseawater records across the MPT. N. Atlantic BWT cooling starting at ∼1.2 Ma, presumably driven by high-latitude cooling, may have been a necessary precursor to a threshold response in climate-ice sheet behavior at ∼900 ka. At that point, a modest increase in ice volume and thermohaline reorganization may have caused enhanced sensitivity to the 100 kyr

  8. The slowdown of the North Atlantic Gulf stream: an economic perspective on adaptation. In: What if... abrupt and extreme climage change?

    NARCIS (Netherlands)

    Ierland, van E.C.

    2008-01-01

    This NWO publication consists the following contributions: Exploring governmental and victim responsibilities in view of abrupt climate change in North-Western Europe; Coping with Extreme Events: Institutional Flocking; Abrupt climate change: Analogies in impacts and coping mechanisms; Catching a co

  9. Climate Change

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Hansen, Ernst Jan de Place

    2011-01-01

    This paper presents the effects of climate change relevant for Denmark, including the change in mean year values as well as the extent of maximum and minimum extremes. Described by the Intergovernmental Panel on Climate Change, the assumptions that the scenarios are based on were outlined...... and evaluated in a Danish context. The uncertainty of the scenarios leaves major challenges that, if not addressed and taken into account in building design, will grow far more serious as climate change progresses. Cases implemented in the Danish building stock illustrate adaptation to climate change...... and illustrate how building design can include mitigating measures to counteract climate change. Cases studied were individual buildings as well as the urban environment. Furthermore the paper describes some of the issues that must be addressed, as the building sector is investing in measures to adapt to climate...

  10. Climate Change

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Hansen, Ernst Jan de Place

    2011-01-01

    and illustrate how building design can include mitigating measures to counteract climate change. Cases studied were individual buildings as well as the urban environment. Furthermore the paper describes some of the issues that must be addressed, as the building sector is investing in measures to adapt to climate......This paper presents the effects of climate change relevant for Denmark, including the change in mean year values as well as the extent of maximum and minimum extremes. Described by the Intergovernmental Panel on Climate Change, the assumptions that the scenarios are based on were outlined...... and evaluated in a Danish context. The uncertainty of the scenarios leaves major challenges that, if not addressed and taken into account in building design, will grow far more serious as climate change progresses. Cases implemented in the Danish building stock illustrate adaptation to climate change...

  11. Climate Change

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Hansen, Ernst Jan de Place

    2011-01-01

    This paper presents the effects of climate change relevant for Denmark, including the change in mean year values as well as the extent of maximum and minimum extremes. Described by the Intergovernmental Panel on Climate Change, the assumptions that the scenarios are based on were outlined...... and evaluated in a Danish context. The uncertainty of the scenarios leaves major challenges that, if not addressed and taken into account in building design, will grow far more serious as climate change progresses. Cases implemented in the Danish building stock illustrate adaptation to climate change...... and illustrate how building design can include mitigating measures to counteract climate change. Cases studied were individual buildings as well as the urban environment. Furthermore the paper describes some of the issues that must be addressed, as the building sector is investing in measures to adapt to climate...

  12. Could massive Arctic sea ice export to the North Atlantic be the real cause of abrupt climate change during the last deglaciation?

    Science.gov (United States)

    Coletti, A. J.; Condron, A.

    2015-12-01

    Using a coupled ocean-sea ice model (MITgcm), we investigate whether the break-up and mobilization of thick, multiyear, Arctic sea ice might have supplied enough freshwater to the Nordic Seas to reduce North Atlantic Deep Water (NADW) formation and weaken the Atlantic Meridional Overturning Circulation (AMOC). Numerical simulations of a Last Glacial Maximum (LGM) environment show the potential for sea ice to grow to ~30m thick, storing ~1.41x105 km3 of freshwater as sea ice in the Arctic (this is ~10 times the volume of freshwater stored in the modern-day Arctic). Releasing this volume of sea ice from the Arctic in 1-yr is equivalent to a high-latitude freshwater forcing of ~4.5 Sv, which is comparable (or larger) in magnitude to most meltwater floods emanating from land-based glacial lakes (e.g. Agassiz) during the last deglaciation. Opening of the Bering Strait and Barents Sea are two plausible mechanisms that may have initiated sea ice mobilization. Opening Bering Strait increases sea ice transport through the Fram Strait by 7% and results in a 22% weakening of AMOC for 2000 years and a >3°C warming in the Arctic basin at 800 m depth. Opening Barents Sea to simulate a collapse of the Fennoscandian ice sheet has little impact on Arctic sea ice and freshwater export to the North Atlantic, but weakens AMOC ~8%. In a simulation with both straits open there is a transition to near-modern sea ice circulation pattern and a 24% reduction in AMOC. Experiments with the Bering Strait open and sea ice artificially capped to 10 m show barely any difference to those when sea ice can grow to ~30m, suggesting that changes in topography have a much greater impact on AMOC than the freshwater forcing from sea ice melting in the Nordic Seas.

  13. Greenland climate change

    DEFF Research Database (Denmark)

    Masson-Delmotte, Valerie; Swingedouw, D.; Landais, A.

    2012-01-01

    Climate archives available from deep-sea and marine shelf sediments, glaciers, lakes and ice cores in and around Greenland allow us to place the current trends in regional climate, ice sheet dynamics, and land surface changes in a broader perspective. We show that during the last decade (2000s...... regional climate and ice sheet dynamics. The magnitude and rate of future changes in Greenland temperature, in response to increasing greenhouse gas emissions, may be faster than any past abrupt events occurring under interglacial conditions. Projections indicate that within one century Greenland may......), atmospheric and sea-surface temperatures are reaching levels last encountered millennia ago when northern high latitude summer insolation was higher due to a different orbital configuration. Concurrently, records from lake sediments in southern Greenland document major environmental and climatic conditions...

  14. Climate change

    NARCIS (Netherlands)

    Marchal, V.; Dellink, R.; Vuuren, D.P. van; Clapp, C.; Chateau, J.; Magné, B.; Lanzi, E.; Vliet, J. van

    2012-01-01

    This chapter analyses the policy implications of the climate change challenge. Are current emission reduction pledges made in Copenhagen/Cancun enough to stabilise the climate and limit global average temperature increase to 2 oC? If not, what will the consequences be? What alternative growth pathwa

  15. A model for abrupt changes in pulsar pulse profile

    Science.gov (United States)

    Yuen, R.; Melrose, D. B.

    2017-08-01

    We propose and explore a purely magnetospheric model for observed abrupt changes in pulsar radio profile. The flow rate of the magnetospheric plasma is dependent on the magnetospheric state described by the parameter y. We include the effect of the motion of the visible point along its trajectory, whose omission from a 'standard' version of viewing geometry is strictly valid only for align rotation and approximately valid for oblique rotation only in a narrow range of pulsar phase, which decreases as the obliquity increases. Emission is assumed from spots, distributed uniformly around the magnetic axis, so that observable features, such as subpulses, appear to rotate at a rate, ωR, relative to the visible point. We find that the apparent motion of an individual spot is not constant, and the apparent distribution of emission spots around the trajectory of the visible point is uneven being highest around the centre of the pulse window, where their apparent motion is slowest, allowing more spots to be present simultaneously in the pulse window than in the 'standard' version. An abrupt (or more gradual) change in y implies a change in ωR, which affects the pulse structure and profile. As a case study, we apply the model to 'swooshing' in PSR B0919+06. We discuss correlated slowing down rate in the model and related time-dependent phenomena in radio pulsars.

  16. Climate Change

    Science.gov (United States)

    ... events, such as hurricanes and wildfires. These can cause death, injuries, stress, and mental health problems. Researchers are studying the best ways to lessen climate change and reduce its impact on our health. NIH: ...

  17. Holocene Abrupt Climate Shifts and Mid-Holocene Drought Intervals Recorded in Barkol Lake of Northern Xinjiang of China

    Institute of Scientific and Technical Information of China (English)

    XUE Jibin; ZHONG Wei; ZHAO Yinjuan; PENG Xiaoying

    2008-01-01

    Study results in this paper have indicated that the Holocene climate in Xinjiang, Northwestern China hasbeen alternating between wet and dry conditions, and was punctuated with a series of abrupt climate shifts. A sedimentcore taken from Barkol Lake in the northern Xinjiang of Northwest China was analyzed at 1 cm interval for grain-sizedistribution. Abrupt climate shifts revealed by the grain-size proxy occurred at ca 1.4, 3.0, 4.3, 5.6, 8.0 cal kyr B.P.,which were well correlated to both the abrupt shifts recorded in the North Atlantic Ocean (NAO) and the Holocene seasurface temperature (SST) cooling events in the Arabian Ocean. The correlation indicated that the climatic changes inthe extreme arid Northwest China were associated with the NAO, probably via the North Atlantic Oscillation-affectedwesterly winds. The strength and position of westerly winds probably modulated the Siberian-Mongolian high-pressure system (winter monsoon), and played an important role in climate change of Northwest China. Moreover, anevident drought interval during the middle Holocene was also revealed by grain-size proxy.

  18. Phase-locked states and abrupt shifts in Pacific climate indices

    Energy Technology Data Exchange (ETDEWEB)

    Douglass, David H., E-mail: douglass@pas.rochester.edu

    2013-10-15

    Douglass has shown that ENSO index aNino3.4 contains segments phase locked to subharmonics of the annual solar cycle and also that a set of indices including aNino3.4 shows abrupt shifts between these phase-locked states. Here, four additional Pacific indices are studied. These five indices show that the Pacific climate system alternates between two regimes: (1) Solar cycle (SOL), (2) Teleconnections (TEL). During SOL each index shows two components that are phase locked to the solar cycle. The first is at the annual cycle, while the second is at a subharmonic of the annual cycle. During TEL abrupt climate shifts occur.

  19. Detection of Abrupt Changes in Runoff in the Weihe River Basin

    Directory of Open Access Journals (Sweden)

    Yanling Li

    2016-01-01

    Full Text Available Climate change and human activities are two major driving factors for variations in hydrological patterns globally, and it is of significant importance to distinguish their effects on the change of hydrological regime in order to formulate robust water management strategies. Hilbert-Huang transform-based time-frequency analysis is employed in this study to detect abrupt changes and periods of the runoff at five hydrological stations in the Weihe River Basin, China, from 1951 to 2010. The key part of the method is the empirical decomposition mode with which any complicated data set can be decomposed into small number of intrinsic mode functions that admit well adaptive Hilbert transforms. Moreover, an attempt has been made to find out the specific reason for the abrupt point at the five hydrological stations in the Weihe River Basin. The results are presented as follows: (1 annual runoff significantly declined in the basin in intervals of 8~15 years; (2 abrupt changes occurred in 1971, 1982, and 1994 at Huaxian, 1972 and 1982 at Xianyang, 1992 at Zhangjiashan, 1990 at Zhuangtou, and 1984 at Beidao; (3 changes were more frequent and complex in the mainstream and downstream reaches than in tributaries and upstream reaches, respectively.

  20. Modeling Abrupt Change in Global Sea Level Arising from Ocean - Ice-Sheet Interaction

    Energy Technology Data Exchange (ETDEWEB)

    Holland, David M

    2011-09-24

    It is proposed to develop, validate, and apply a coupled ocean ice-sheet model to simulate possible, abrupt future change in global sea level. This research is to be carried out collaboratively between an academic institute and a Department of Energy Laboratory (DOE), namely, the PI and a graduate student at New York University (NYU) and climate model researchers at the Los Alamos National Laboratory (LANL). The NYU contribution is mainly in the area of incorporating new physical processes into the model, while the LANL efforts are focused on improved numerics and overall model development. NYU and LANL will work together on applying the model to a variety of modeling scenarios of recent past and possible near-future abrupt change to the configuration of the periphery of the major ice sheets. The project's ultimate goal is to provide a robust, accurate prediction of future global sea level change, a feat that no fully-coupled climate model is currently capable of producing. This proposal seeks to advance that ultimate goal by developing, validating, and applying a regional model that can simulate the detailed processes involved in sea-level change due to ocean ice-sheet interaction. Directly modeling ocean ice-sheet processes in a fully-coupled global climate model is not a feasible activity at present given the near-complete absence of development of any such causal mechanism in these models to date.

  1. Environments of ocean and primary productivity during the late Quaternary. Millenial-scale large and abrupt climatic changes (global system dynamics in response to Dansgaard-Oeschger cycles); Daiyonki koki no kaiyo kankyo to seibutsu seisan. Suhyaku-susennen scale no kyugekina kiko hendo (Dansgaard-Oeschger cycle ni taisuru chikyu system no oto)

    Energy Technology Data Exchange (ETDEWEB)

    Tada, R. [The University of Tokyo, Tokyo (Japan)

    1998-04-25

    Abrupt and steep climate changes of the millennial scale as represented by the Dansgaard-Oeschger cycle (D-O cycle) and the behavior of the global surface layer system in their wake are outlined. The D-DO cycle is the abrupt and steep climate changes that are recorded in the Greenland continental ice sheet, and is grasped most typically as changes in the oxygen isotopic ratio in the ice. Studies reveal that the D-O cycle is a global episode that accompanied interaction between various subsystems constituting the global surface layer system. It is believed that in the D-O cycle there were changes not only in temperature but also in aridity/moisture and in the sea level, and probabilities are high that there was a great local variation in the way the changes took effect. The possibility has now become lower that the D-O cycle occurred in the interglacial epoch in the high latitude belt in the northern hemisphere, yet it remains likely that the climate changes driving the D-O cycle continued in the low latitude belt. 57 refs., 8 figs.

  2. Climatic changes

    DEFF Research Database (Denmark)

    Majgaard Krarup, Jonna

    2014-01-01

    According to Cleo Paskal climatic changes are environmental changes. They are global, but their impact is local, and manifests them selves in the landscape, in our cities, in open urban spaces, and in everyday life. The landscape and open public spaces will in many cases be the sites where...... be addressed in order to develop and support social sustainability and identification. This paper explore and discuss how the handling of climatic changes in landscape and open urban spaces might hold a potential for them to become common goods....... spaces. From Henri LeFebvre’s thinking we learn that the production of space is a feed back loop, where the space is constructed when we attach meaning to it, and when the space offers meaning to us. Spatial identity is thus not the same as identifying with space. Without indentifying with space, space...

  3. Drivers and Dynamics of Ecological Responses to Abrupt Environmental Change on the Early Miocene Oregon Shelf

    Science.gov (United States)

    Belanger, C. L.

    2012-12-01

    We know that the biosphere responds to abrupt climate change, but know less about the dynamics of those changes and their proximal drivers. Studies of well-preserved fossil time-series spanning past climate events that utilize multiple environmental proxies and examine multiple taxonomic groups can provide critical insight into (a) the specific environmental factors to which the biota respond, (b) the rate and tempo of those responses, and (c) whether taxonomic groups respond similarly or differently to the same stresses. I examine the drivers and dynamics of ecological changes in continental shelf benthic foraminifera and molluscs from the Early Miocene Newport Member of the Astoria Formation in Oregon (20.3-16.3 mya), which spans a time of global warming leading into the Middle Miocene Climate Optimum. Stable isotope (δ18O) data from three species of benthic foraminifera from the Astoria sediments indicate that the region abruptly warmed by 2-4°C approximately 19 mya. In addition, δ13C values from epifaunal and infaunal foraminifera indicate an increase in productivity and organic carbon flux over time. Further, an increase in δ15N from bulk sediment and an increase in sedimentary laminations suggest oxygen levels declined. Multivariate analyses demonstrate a strong correlation between foraminiferal community metrics and δ15N suggesting that the foraminiferal community is tracking oxygenation levels while correlations to productivity changes appear indirect. Molluscan community metrics also have an approximately linear relationship to δ15N. Temperature itself had little direct influence on community composition. Changes in community composition and structure of both the foraminifera and the molluscs are abrupt relative to the duration of community states, but each group responds differently to the climate change. The foraminiferal community increases in the number of species and the evenness of species abundances while the molluscan community decreases in

  4. Extreme temperatures, foundation species, and abrupt ecosystem change: an example from an iconic seagrass ecosystem.

    Science.gov (United States)

    Thomson, Jordan A; Burkholder, Derek A; Heithaus, Michael R; Fourqurean, James W; Fraser, Matthew W; Statton, John; Kendrick, Gary A

    2015-04-01

    Extreme climatic events can trigger abrupt and often lasting change in ecosystems via the reduction or elimination of foundation (i.e., habitat-forming) species. However, while the frequency/intensity of extreme events is predicted to increase under climate change, the impact of these events on many foundation species and the ecosystems they support remains poorly understood. Here, we use the iconic seagrass meadows of Shark Bay, Western Australia--a relatively pristine subtropical embayment whose dominant, canopy-forming seagrass, Amphibolis antarctica, is a temperate species growing near its low-latitude range limit--as a model system to investigate the impacts of extreme temperatures on ecosystems supported by thermally sensitive foundation species in a changing climate. Following an unprecedented marine heat wave in late summer 2010/11, A. antarctica experienced catastrophic (>90%) dieback in several regions of Shark Bay. Animal-borne video footage taken from the perspective of resident, seagrass-associated megafauna (sea turtles) revealed severe habitat degradation after the event compared with a decade earlier. This reduction in habitat quality corresponded with a decline in the health status of largely herbivorous green turtles (Chelonia mydas) in the 2 years following the heat wave, providing evidence of long-term, community-level impacts of the event. Based on these findings, and similar examples from diverse ecosystems, we argue that a generalized framework for assessing the vulnerability of ecosystems to abrupt change associated with the loss of foundation species is needed to accurately predict ecosystem trajectories in a changing climate. This includes seagrass meadows, which have received relatively little attention in this context. Novel research and monitoring methods, such as the analysis of habitat and environmental data from animal-borne video and data-logging systems, can make an important contribution to this framework.

  5. Detecting and isolating abrupt changes in linear switching systems

    Science.gov (United States)

    Nazari, Sohail; Zhao, Qing; Huang, Biao

    2015-04-01

    In this paper, a novel fault detection and isolation (FDI) method for switching linear systems is developed. All input and output signals are assumed to be corrupted with measurement noises. In the proposed method, a 'lifted' linear model named as stochastic hybrid decoupling polynomial (SHDP) is introduced. The SHDP model governs the dynamics of the switching linear system with all different modes, and is independent of the switching sequence. The error-in-variable (EIV) representation of SHDP is derived, and is used for the fault residual generation and isolation following the well-adopted local approach. The proposed FDI method can detect and isolate the fault-induced abrupt changes in switching models' parameters without estimating the switching modes. Furthermore, in this paper, the analytical expressions of the gradient vector and Hessian matrix are obtained based on the EIV SHDP formulation, so that they can be used to implement the online fault detection scheme. The performance of the proposed method is then illustrated by simulation examples.

  6. Abrupt Strategy Change Underlies Gradual Performance Change: Bayesian Hierarchical Models of Component and Aggregate Strategy Use.

    Science.gov (United States)

    Wynton, Sarah K A; Anglim, Jeromy

    2017-04-10

    While researchers have often sought to understand the learning curve in terms of multiple component processes, few studies have measured and mathematically modeled these processes on a complex task. In particular, there remains a need to reconcile how abrupt changes in strategy use can co-occur with gradual changes in task completion time. Thus, the current study aimed to assess the degree to which strategy change was abrupt or gradual, and whether strategy aggregation could partially explain gradual performance change. It also aimed to show how Bayesian methods could be used to model the effect of practice on strategy use. To achieve these aims, 162 participants completed 15 blocks of practice on a complex computer-based task-the Wynton-Anglim booking (WAB) task. The task allowed for multiple component strategies (i.e., memory retrieval, information reduction, and insight) that could also be aggregated to a global measure of strategy use. Bayesian hierarchical models were used to compare abrupt and gradual functions of component and aggregate strategy use. Task completion time was well-modeled by a power function, and global strategy use explained substantial variance in performance. Change in component strategy use tended to be abrupt, whereas change in global strategy use was gradual and well-modeled by a power function. Thus, differential timing of component strategy shifts leads to gradual changes in overall strategy efficiency, and this provides one reason for why smooth learning curves can co-occur with abrupt changes in strategy use. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Abrupt response of chemical weathering to Late Quaternary hydroclimate changes in northeast Africa

    Science.gov (United States)

    Bastian, Luc; Revel, Marie; Bayon, Germain; Dufour, Aurélie; Vigier, Nathalie

    2017-01-01

    Chemical weathering of silicate rocks on continents acts as a major sink for atmospheric carbon dioxide and has played an important role in the evolution of the Earth’s climate. However, the magnitude and the nature of the links between weathering and climate are still under debate. In particular, the timescale over which chemical weathering may respond to climate change is yet to be constrained at the continental scale. Here we reconstruct the relationships between rainfall and chemical weathering in northeast Africa for the last 32,000 years. Using lithium isotopes and other geochemical proxies in the clay-size fraction of a marine sediment core from the Eastern Mediterranean Sea, we show that chemical weathering in the Nile Basin fluctuated in parallel with the monsoon-related climatic evolution of northeast Africa. We also evidence strongly reduced mineral alteration during centennial-scale regional drought episodes. Our findings indicate that silicate weathering may respond as quickly as physical erosion to abrupt hydroclimate reorganization on continents. Consequently, we anticipate that the forthcoming hydrological disturbances predicted for northeast Africa may have a major impact on chemical weathering patterns and soil resources in this region. PMID:28290474

  8. Abrupt response of chemical weathering to Late Quaternary hydroclimate changes in northeast Africa

    Science.gov (United States)

    Bastian, Luc; Revel, Marie; Bayon, Germain; Dufour, Aurélie; Vigier, Nathalie

    2017-03-01

    Chemical weathering of silicate rocks on continents acts as a major sink for atmospheric carbon dioxide and has played an important role in the evolution of the Earth’s climate. However, the magnitude and the nature of the links between weathering and climate are still under debate. In particular, the timescale over which chemical weathering may respond to climate change is yet to be constrained at the continental scale. Here we reconstruct the relationships between rainfall and chemical weathering in northeast Africa for the last 32,000 years. Using lithium isotopes and other geochemical proxies in the clay-size fraction of a marine sediment core from the Eastern Mediterranean Sea, we show that chemical weathering in the Nile Basin fluctuated in parallel with the monsoon-related climatic evolution of northeast Africa. We also evidence strongly reduced mineral alteration during centennial-scale regional drought episodes. Our findings indicate that silicate weathering may respond as quickly as physical erosion to abrupt hydroclimate reorganization on continents. Consequently, we anticipate that the forthcoming hydrological disturbances predicted for northeast Africa may have a major impact on chemical weathering patterns and soil resources in this region.

  9. Detecting Abrupt Change of Streamflow at Lintong Station of Wei River

    Directory of Open Access Journals (Sweden)

    Jingjing Fan

    2013-01-01

    Full Text Available According to abrupt diagnosis of runoff, two methods, that is, moving approximate entropy and moving permutation entropy, are used to analyse the abrupt year of the daily river runoff from 1961 to 2006 at Lintong station of Wei River in Loess Plateau. The runoff series are divided into 4 stages. With the analysis of hydrological characters of different stages, we find that there are abrupt changes at the three years 1972, 1983, and 2002. The result shows that moving approximate entropy and moving permutation entropy methods are useful tools for abrupt diagnosis of runoff. The attribution of abrupt change at the Lintong runoff series is primarily due to the reduced precipitation, increased water conservancy project, increased water consumption of industry and agriculture, significantly decreased groundwater table, and increased evaporation.

  10. How children change their minds: strategy change can be gradual or abrupt.

    Science.gov (United States)

    Alibali, M W

    1999-01-01

    This study investigated patterns of change in children's strategies for solving mathematical equivalence problems. The strategies children expressed in speech and in gesture were assessed both before and after an instructional intervention. In the intervention, children received either no input, accuracy feedback, or feedback plus instruction about a principle, an analogy, or a procedure. From pretest to posttest, many children changed both the variability of their strategy use and the content of their strategy repertoires. Patterns of change depended on type of instruction and on children's initial level of variability. Children who received instruction were especially likely to generate new strategies, and children with high variability were especially likely to abandon prior strategies. Gradual change was most common; however, many children modified their repertoires abruptly. Abrupt strategy change was especially prevalent among children who received procedure-based instruction and among children with low initial variability.

  11. Extrinsic regime shifts drive abrupt changes in regeneration dynamics at upper treeline in the Rocky Mountains, U.S.A.

    Science.gov (United States)

    Elliott, Grant P

    2012-07-01

    Given the widespread and often dramatic influence of climate change on terrestrial ecosystems, it is increasingly common for abrupt threshold changes to occur, yet explicitly testing for climate and ecological regime shifts is lacking in climatically sensitive upper treeline ecotones. In this study, quantitative evidence based on empirical data is provided to support the key role of extrinsic, climate-induced thresholds in governing the spatial and temporal patterns of tree establishment in these high-elevation environments. Dendroecological techniques were used to reconstruct a 420-year history of regeneration dynamics within upper treeline ecotones along a latitudinal gradient (approximately 44-35 degrees N) in the Rocky Mountains. Correlation analysis was used to assess the possible influence of minimum and maximum temperature indices and cool-season (November-April) precipitation on regional age-structure data. Regime-shift analysis was used to detect thresholds in tree establishment during the entire period of record (1580-2000), temperature variables significantly Correlated with establishment during the 20th century, and cool-season precipitation. Tree establishment was significantly correlated with minimum temperature during the spring (March-May) and cool season. Regime-shift analysis identified an abrupt increase in regional tree establishment in 1950 (1950-1954 age class). Coincident with this period was a shift toward reduced cool-season precipitation. The alignment of these climate conditions apparently triggered an abrupt increase in establishment that was unprecedented during the period of record. Two main findings emerge from this research that underscore the critical role of climate in governing regeneration dynamics within upper treeline ecotones. (1) Regional climate variability is capable of exceeding bioclimatic thresholds, thereby initiating synchronous and abrupt changes in the spatial and temporal patterns of tree establishment at broad

  12. Spatiotemporal Variation and Abrupt Change Analysis of Temperature from 1960 to 2012 in the Huang-Huai-Hai Plain, China

    Directory of Open Access Journals (Sweden)

    Yanyu Yin

    2015-01-01

    Full Text Available Based on a monthly dataset of temperature time series (1960–2012 in the Huang-Huai-Hai Plain of China (HHHPC, spatiotemporal variation and abrupt change analysis of temperature were examined by moving average, linear regression, spline interpolation, Mann-Kendall test, and moving t-test. Major conclusions were listed as follows. (1 Annual and seasonal temperature increased with different rates on the process of fluctuating changes during 1960~2012. The upward trend was 0.22°C 10a−1 for annual temperature, while it was very significant in winter (0.34°C 10a−1 and spring (0.31°C 10a−1, moderately significant in autumn (0.21°C 10a−1, and nonsignificant in summer (0.05°C 10a−1. (2 The spatial changes of annual and seasonal temperature were similar. The temperature increased significantly in Beijing and its adjacent regions, while it was nonsignificant in the central and southern regions. (3 The spring, autumn, winter, and annual temperature had warm abrupt change. The abrupt change time for winter temperature was in the late 1970s, while it was in the late 1980s and early 1990s for spring, autumn, and annual temperature. (4 Macroscopic effects of global and regional climate warming and human activities were probably responsible for the temperature changes. The climate warming would influence the hydrological cycle and agricultural crops in the study area.

  13. Could gradual changes in Holocene Saharan landscape have caused the observed abrupt shift in North Atlantic dust deposition?

    Science.gov (United States)

    Egerer, Sabine; Claussen, Martin; Reick, Christian; Stanelle, Tanja

    2017-09-01

    The abrupt change in North Atlantic dust deposition found in sediment records has been associated with a rapid large scale transition of Holocene Saharan landscape. We hypothesize that gradual changes in the landscape may have caused this abrupt shift in dust deposition either because of the non-linearity in dust activation or because of the heterogeneous distribution of major dust sources. To test this hypothesis, we investigate the response of North Atlantic dust deposition to a prescribed 1) gradual and spatially homogeneous decrease and 2) gradual southward retreat of North African vegetation and lakes during the Holocene using the aerosol-climate model ECHAM-HAM. In our simulations, we do not find evidence of an abrupt increase in dust deposition as observed in marine sediment records along the Northwest African margin. We conclude that such gradual changes in landscape are not sufficient to explain the observed abrupt changes in dust accumulation in marine sediment records. Instead, our results point to a rapid large-scale retreat of vegetation and lakes in the area of significant dust sources.

  14. Abrupt spatiotemporal land and water changes and their potential drivers in Poyang Lake, 2000-2012

    Science.gov (United States)

    Chen, Lifan; Michishita, Ryo; Xu, Bing

    2014-12-01

    Driven by various natural and anthropogenic factors, Poyang Lake, the largest freshwater lake in China, has experienced significant land use/cover changes in the past few decades. The aim of this study is to investigate the spatial-temporal patterns of abrupt changes and detect their potential drivers in Poyang Lake, using time-series Moderate Resolution Imaging Spectroradiometer (MODIS) 16-day maximum value composite vegetation indices between 2000 and 2012. The breaks for additive seasonal and trend (BFAST) method was applied to the smoothed time-series normalized difference vegetation index (NDVI), to detect the timing and magnitude of abrupt changes in the trend component. Large part of Poyang Lake (98.9% for trend component) has experienced abrupt changes in the past 13 years, and the change patterns, including the distributions in timing and magnitudes of major abrupt trend changes between water bodies and land areas were clearly differentiated. Most water bodies had abrupt increasing NDVI changes between 2010 and 2011, caused by the sequential severe flooding and drought in the two years. In contrast, large parts of the surrounding land areas had abrupt decreasing NDVI changes. Large decreasing changes occurred around 2003 at the city of Nanchang, which were driven by urbanization. These results revealed spatial-temporal land cover changing patterns and potential drivers in the wetland ecosystem of Poyang Lake.

  15. Ecosystem resilience to abrupt late Quaternary change in continental southern Siberia

    Science.gov (United States)

    Harding, Poppy; Mackay, Anson; Bezrukova, Elena; Shchetnikov, Alexander

    2017-04-01

    Quaternary climate variability is dominated by long term orbital forcing along with abrupt sub-Milankovitch events on the scales of millennia to centuries, driven by internal feedback mechanisms, volcanic forcing and fluctuating solar activity. Although these are well documented in the North Atlantic region, their expression is poorly understood in Siberia, particularly in relation to abrupt climatic events. Siberia has the world's highest level of continentality offering an opportunity to study changes remote from oceanic influences and improving understanding of interactions between the Siberian High and other atmospheric systems including the Aleutian Low, Arctic oscillation and Icelandic Low1 and ENSO2. Understanding of palaeoenvironmental change in Siberia is essential due to the region's high sensitivity to climatic change, with warming rates considerably higher than the global average over the past 50 years3, triggering significant environmental changes, including permafrost degradation, shifts in the forest-steppe biome, increases in forest fires and warming of seasonally ice-covered lakes. Additionally, the region provides essential palaeoenvironmental context for early hominins, for example at globally important sites such as Denisova cave4, and megafauna extinctions5. This presentation outlines ongoing work at Lake Baunt, SE Siberia including: key quaternary climate forcings, the site and its regional context, the key methods and preliminary results. These include a dated record back to ˜30ka BP (based on multiple 14C dates and Bayesian age modelling), multiproxy indicators of palaeoproductivity (e.g. biogenic silica and diatom analyses) and lake mixing regimes (inferred from diatom analyses). Together these highlight several key Quaternary fluctuations potentially correlated to events recorded in Greenland Ice Cores (GS2, GS2.1, GI1, GS1), and these are considered against key Quaternary records including those from nearby Lake Baikal and Hulu Cave in

  16. Agriculture: Climate Change

    Science.gov (United States)

    Climate change affects agricultural producers because agriculture and fisheries depend on specific climate conditions. Temperature changes can cause crop planting dates to shift. Droughts and floods due to climate change may hinder farming practices.

  17. Climate Change

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    According to the National Academy of Sciences in American,the Earth's surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades. There is new and stronger evidence that most of the warming over the last 50 years is attributable to human activities.Human activities have altered the chemical composition of the atmosphere through the buildup of greenhouse gases-primarily carbon dioxide, methane, and nitrous oxide. The heat-trapping property of these gases is undisputed although uncertainties exist about exactly how earth's climate responds to them.

  18. Abrupt pre-Bølling-Allerød warming and circulation changes in the deep ocean.

    Science.gov (United States)

    Thiagarajan, Nivedita; Subhas, Adam V; Southon, John R; Eiler, John M; Adkins, Jess F

    2014-07-03

    Several large and rapid changes in atmospheric temperature and the partial pressure of carbon dioxide in the atmosphere--probably linked to changes in deep ocean circulation--occurred during the last deglaciation. The abrupt temperature rise in the Northern Hemisphere and the restart of the Atlantic meridional overturning circulation at the start of the Bølling-Allerød interstadial, 14,700 years ago, are among the most dramatic deglacial events, but their underlying physical causes are not known. Here we show that the release of heat from warm waters in the deep North Atlantic Ocean probably triggered the Bølling-Allerød warming and reinvigoration of the Atlantic meridional overturning circulation. Our results are based on coupled radiocarbon and uranium-series dates, along with clumped isotope temperature estimates, from water column profiles of fossil deep-sea corals in a limited area of the western North Atlantic. We find that during Heinrich stadial 1 (the cool period immediately before the Bølling-Allerød interstadial), the deep ocean was about three degrees Celsius warmer than shallower waters above. This reversal of the ocean's usual thermal stratification pre-dates the Bølling-Allerød warming and must have been associated with increased salinity at depth to preserve the static stability of the water column. The depleted radiocarbon content of the warm and salty water mass implies a long-term disconnect from rapid surface exchanges, and, although uncertainties remain, is most consistent with a Southern Ocean source. The Heinrich stadial 1 ocean profile is distinct from the modern water column, that for the Last Glacial Maximum and that for the Younger Dryas, suggesting that the patterns we observe are a unique feature of the deglacial climate system. Our observations indicate that the deep ocean influenced dramatic Northern Hemisphere warming by storing heat at depth that preconditioned the system for a subsequent abrupt overturning event during the

  19. Climate Change Schools Project...

    Science.gov (United States)

    McKinzey, Krista

    2010-01-01

    This article features the award-winning Climate Change Schools Project which aims to: (1) help schools to embed climate change throughout the national curriculum; and (2) showcase schools as "beacons" for climate change teaching, learning, and positive action in their local communities. Operating since 2007, the Climate Change Schools…

  20. Climate Change Schools Project...

    Science.gov (United States)

    McKinzey, Krista

    2010-01-01

    This article features the award-winning Climate Change Schools Project which aims to: (1) help schools to embed climate change throughout the national curriculum; and (2) showcase schools as "beacons" for climate change teaching, learning, and positive action in their local communities. Operating since 2007, the Climate Change Schools Project…

  1. Climate Change Schools Project...

    Science.gov (United States)

    McKinzey, Krista

    2010-01-01

    This article features the award-winning Climate Change Schools Project which aims to: (1) help schools to embed climate change throughout the national curriculum; and (2) showcase schools as "beacons" for climate change teaching, learning, and positive action in their local communities. Operating since 2007, the Climate Change Schools…

  2. Climate Change Indicators

    Science.gov (United States)

    Presents information, charts and graphs showing measured climate changes across 40 indicators related to greenhouse gases, weather and climate, oceans, snow and ice, heath and society, and ecosystems.

  3. CLIMATE CHANGE, Change International Negociations?

    Institute of Scientific and Technical Information of China (English)

    Gao Xiaosheng

    2009-01-01

    @@ Climate change is one of key threats to human beings who have to deal with.According to Bali Action Plan released after the 2007 Bali Climate Talk held in Indonesia,the United Nations Framework on Climate Change(UNFCCC) has launched a two-year process to negotiate a post-2012 climate arrangement after the Kyoto Protocol expires in 2012 and the Copenhagen Climate Change Conference will seal a final deal on post-2012 climate regime in December,2009.For this,the United Nation Chief Ban Ki Moon called 2009"the year ofclimate change".

  4. Events of abrupt change ofIndian monsoon recorded in Dasuopu ice core fromHimalayas

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Three ice cores distributed across Dasuopu glacier in Himalayas were recovered. A 400-year net annual accumulation record reconstructed from one of the cores reflects the major precipitation trend in the central Himalayas. This record is related closely to the Indian monsoon precipitation. Wavelet and moving T-test were applied to the 400-year-long Dasuopu accumulation record, and significant staggered variability and abrupt change of the record on interannual to centennial time scales are identified. Finally the possible reason for abrupt change of the accumulation record is discussed.

  5. Detection of abrupt baseline length changes using cumulative sums

    Science.gov (United States)

    Janssen, Volker

    2009-06-01

    Dynamic processes are usually monitored by collecting a time series of observations, which is then analysed in order to detect any motion or non-standard behaviour. Geodetic examples include the monitoring of dams, bridges, high-rise buildings, landslides, volcanoes and tectonic motion. The cumulative sum (CUSUM) test is recognised as a popular means to detect changes in the mean and/or the standard deviation of a time series and has been applied to various monitoring tasks. This paper briefly describes the CUSUM technique and how it can be utilised for the detection of small baseline length changes by differencing two perpendicular baselines sharing a common site. A simulation is carried out in order to investigate the expected behaviour of the resulting CUSUM charts for a variety of typical deformation monitoring scenarios. This simulation shows that using first differences (between successive epochs) as input, rather than the original baseline lengths, produces clear peaks or jumps in the differenced CUSUM time series when a sudden change in baseline length occurs. These findings are validated by analysing several GPS baseline pairs of a network deployed to monitor the propagation of an active ice shelf rift on the Amery Ice Shelf, East Antarctica.

  6. Abrupt transition from natural to anthropogenic aerosol radiative forcing: Observations at the ABC-Maldives Climate Observatory

    Science.gov (United States)

    Ramana, M. V.; Ramanathan, V.

    2006-10-01

    Using aerosol-radiation observations over the north Indian Ocean, we show how the monsoon transition from southwest to northeast flow gives rise to a similar transition in the direct aerosol radiative forcing from natural to anthropogenic forcing. These observations were taken at the newly built aerosol-radiation-climate observatory at the island of Hanimaadhoo (6.776°N, 73.183°E) in the Republic of Maldives. This observatory is established as a part of Project Atmospheric Brown Clouds (ABC) and is referred to as the ABC-Maldives Climate Observatory at Hanimaadhoo (ABC_MCOH). The transition from the southwest monsoon during October to the northeast monsoon flow during early November occurs abruptly over a period of few weeks over ABC-MCOH and reveals a dramatic contrast between the natural marine aerosols transported from the south Indian Ocean by the southwest monsoon and that of the polluted aerosols transported from the south and Southeast Asian region by the northeast monsoon. We document the change in the microphysical properties and the irradiance at the surface, to identify the human signature on aerosol radiative forcing. We first establish the precision of surface radiometric observations by comparing simultaneous observations using calibrated Kipp & Zonen and Eppley pyrheliometers and pyranometers for direct, diffuse and global solar radiation. We show that the direct, diffuse and global radiation can be measured within a precision of about 3 to 5 Wm-2. Furthermore, when we include the observed aerosol optical properties as input into the Monte Carlo Aerosol Cloud Radiation (MACR) model (developed by us using Indian Ocean Experiment data), the simulated fluxes agree with the observed direct, diffuse and global fluxes within the measurement accuracy. A steady southwest monsoon flow of about 5 to 7 ms-1 persists until middle of October which switches to an abrupt change in direction to northeast flow of similar speeds bringing in polluted air from south

  7. Abrupt change of Antarctic moisture origin at the end of Termination II.

    Science.gov (United States)

    Masson-Delmotte, V; Stenni, B; Blunier, T; Cattani, O; Chappellaz, J; Cheng, H; Dreyfus, G; Edwards, R L; Falourd, S; Govin, A; Kawamura, K; Johnsen, S J; Jouzel, J; Landais, A; Lemieux-Dudon, B; Lourantou, A; Marshall, G; Minster, B; Mudelsee, M; Pol, K; Röthlisberger, R; Selmo, E; Waelbroeck, C

    2010-07-01

    The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C East Antarctic ice core provide new insights on the sequence of events involved in Termination II, the transition between the penultimate glacial and interglacial periods. This termination is marked by a north-south seesaw behavior, with first a slow methane concentration rise associated with a strong Antarctic temperature warming and a slow deuterium excess rise. This first step is followed by an abrupt north Atlantic warming, an abrupt resumption of the East Asian summer monsoon, a sharp methane rise, and a CO(2) overshoot, which coincide within dating uncertainties with the end of Antarctic optimum. Here, we show that this second phase is marked by a very sharp Dome C centennial deuterium excess rise, revealing abrupt reorganization of atmospheric circulation in the southern Indian Ocean sector.

  8. Use of abrupt strain path change for determining subsequent yield surface

    DEFF Research Database (Denmark)

    Kuwabara, T.; Kuroda, M.; Tvergaard, Viggo

    2000-01-01

    . In a biaxial tensile testing apparatus, a cruciform specimen is used, with the strains measured by a biaxial-strain gauge. Then, with the hydraulic pressure of two sets of opposing hydraulic cylinders servo-controlled independently, the testing apparatus can be used to prescribe an abrupt change of the strain...

  9. Climate for Change?

    DEFF Research Database (Denmark)

    Wejs, Anja

    ’ results are presented in five journal articles. The articles’ areas of investigation take as their point of departure three planning areas that serve as planning tools for climate change integration: climate change planning, municipal spatial planning and strategic environmental assessment (SEA......Cities rather than national governments take the lead in acting on climate change. Several cities have voluntarily created climate change plans to prevent and prepare for the effects of climate change. In the literature climate change has been examined as a multilevel governance area taking place...... the constraints on climate change planning at the local level are absent. To understand these constraints, this PhD thesis investigates the institutional dynamics that influence the process of the integration of climate change into planning practices at the local level in Denmark. The examination of integration...

  10. Climate Change and Health

    Science.gov (United States)

    ... sheets Fact files Questions & answers Features Multimedia Contacts Climate change and health Fact sheet Reviewed June 2016 Key ... in improved health, particularly through reduced air pollution. Climate change Over the last 50 years, human activities – particularly ...

  11. Climate Change Law

    NARCIS (Netherlands)

    Farber, D.A.; Peeters, Marjan

    2016-01-01

    This book brings together over seventy fifty authors for a comprehensive examination of the emerging global regime of climate change law. Despite the relative youth of climate change law, we can already begin to see the outlines of legal regimes addressing climate change mitigation and adaptation (a

  12. Rethinking species’ ability to cope with rapid climate change

    DEFF Research Database (Denmark)

    Hof, Christian; Levinsky, Irina; Bastos Araujo, Miguel

    2011-01-01

    than contemporary ones, but relatively few continent-wide extinctions of species have been documented for these periods. This raises questions about the ability of extant species to adapt to ongoing climate change. We propose that the advances in geophysical research challenge current views about......Ongoing climate change is assumed to be exceptional because of its unprecedented velocity. However, new geophysical research suggests that dramatic climatic changes during the Late Pleistocene occurred extremely rapid, over just a few years. These abrupt climatic changes may have been even faster...... species' ability to cope with climate change, and that lessons must be learned for modelling future impacts of climate change on species....

  13. Education and Climate Change: Living and Learning in Interesting Times

    Science.gov (United States)

    Kagawa, Fumiyo, Ed.; Selby, David, Ed.

    2009-01-01

    There is widespread consensus in the international scientific community that climate change is happening and that abrupt and irreversible impacts are already set in motion. What part does education have to play in helping alleviate rampant climate change and in mitigating its worst effects? In this volume, contributors review and reflect upon…

  14. Climate change assessments

    Science.gov (United States)

    Linda A. Joyce

    2008-01-01

    The science associated with climate and its effects on ecosystems, economies, and social systems is developing rapidly. Climate change assessments can serve as an important synthesis of this science and provide the information and context for management and policy decisions on adaptation and mitigation. This topic paper describes the variety of climate change...

  15. Trend, abrupt change, and periodicity of streamflow in the mainstream of Yellow River.

    Science.gov (United States)

    He, Bin; Miao, Chiyuan; Shi, Wen

    2013-07-01

    The Yellow River is the second largest river in China. The annual runoff of which is only about 2% of China's total, but contributes to 9% of China's GDP and directly supports 12% of the population. Today, the water shortage in the Yellow River basin has been aggravated due to rapid population growth and global warming. In order to best maximize water resources management, the natural and observed streamflow series from six hydrologic gauging stations (Guide, Lanzhou, Hekou, Sanmenxia, Huayuankou, and Lijin) are obtained, and the linear regression, Mann-Kendall test, and wavelet transform methods were used to detect the characteristic of streamflow variation from 1956 to 2007. The results show that: (1) both the natural streamflow and observed streamflow present a downward trend over the past 52 years, and the trends are intensified downstream; the decreasing rate of observed streamflow is more rapid than that of the natural streamflow; (2) most of the abrupt changes in natural streamflow and observed streamflow appear in the late 1980s to early 1990s through the result of the Mann-Kendall test; and (3) other than the Guide station, the streamflows at the rest of the stations appear to have strongest periodicity of 19-21 years with a 52-year scale. The results of this study imply that less precipitation and warmer climate in the basin are the primary factors that cause this decreasing trend of natural streamflow. Additionally, the rapid ascent of water consumption by human being results in the reduction of observed streamflow further. Furthermore, human activities like reservoir construction, soil and water conservation measures, etc. influence the streamflow as well. It is recommended that the society takes some effective countermeasures to cope with the water shortage.

  16. Asking about climate change

    DEFF Research Database (Denmark)

    Nielsen, Jonas Østergaard; D'haen, Sarah Ann Lise

    2014-01-01

    There is increasing evidence that climate change will strongly affect people across the globe. Likely impacts of and adaptations to climate change are drawing the attention of researchers from many disciplines. In adaptation research focus is often on perceptions of climate change...... and on vulnerability and adaptation strategies in a particular region or community. But how do we research the ways in which people experience changing climatic conditions, the processes of decision-making, the actual adaptation strategies carried out and the consequences of these for actors living and dealing...... with climate change? On the basis of a literature review of all articles published in Global Environmental Change between 2000 and 2012 that deal with human dimensions of climate change using qualitative methods this paper provides some answers but also raises some concerns. The period and length of fieldwork...

  17. Reconstruction of hydrologic responses to late-Glacial (9-33ka) abrupt climate transitions in the coastal southwest United States

    Science.gov (United States)

    Wu, M.; Feakins, S. J.; Kirby, M. E.

    2013-12-01

    A sediment core retrieved from Lake Elsinore, the largest natural freshwater lake in southern California, spans an age of 9 to 33ka BP. The period includes several late-Glacial abrupt climate transitions such as the Heinrich events (HEs) 1-3, the Bølling-Allerød (B-A), and the Younger Dryas (YD). This terrestrial site provides a unique opportunity to evaluate changes in hydrology in coastal southwest United States across these key abrupt climate transition events. Hydrogen isotopic ratios (δDwax) of the long-chain C28 alkanoic acid, a biomarker for terrestrial leaf wax, extracted from the sediments, were analyzed to reveal the δD of precipitation water in the past (δDprecip). In the modern climate, higher δDprecip values are associated with moisture sourced from the tropical Pacific, which brings a drier and warmer climate, whereas lower δDprecip values are associated with moisture sourced from north Pacific brought by polar jet stream, causing a wetter and colder climate. δDwax ranges from about -210‰ to -100‰ between late-Glacial HEs and the beginning of Holocene. The pattern generally correlates with Greenland ice core and regional speleothem records, with lower δDwax values corresponding to colder periods (HEs), and higher δDwax values corresponding to warmer periods (B-A and early Holocene). We infer cold and wet climate with north Pacific sourced moisture during the glacial, followed by gradual warming and drying into the B-A and Holocene, when the moisture sources shifted to the tropical Pacific. There is no substantive response to the YD. The fluctuations of δDwax into and out of the HEs can be as large as about 60‰, suggesting greatly variable hydrology across these late-Glacial abrupt climate transition events. The large shifts in δDwax signal during deglaciation and HEs indicate that hydrology in the coastal southwest US has responded sensitively to climate change, and therefore has important implications for water resources in this

  18. Characterizing abrupt changes in the stock prices using a wavelet decomposition method

    Science.gov (United States)

    Caetano, Marco Antonio Leonel; Yoneyama, Takashi

    2007-09-01

    Abrupt changes in the stock prices, either upwards or downwards, are usually preceded by an oscillatory behavior with frequencies that tend to increase as the moment of transition becomes closer. The wavelet decomposition methods may be useful for analysis of this oscillations with varying frequencies, because they provide simultaneous information on the frequency (scale) and localization in time (translation). However, in order to use the wavelet decomposition, certain requirements have to be satisfied, so that the linear and cyclic trends are eliminated by standard least squares techniques. The coefficients obtained by the wavelet decomposition can be represented in a graphical form. A threshold can then be established to characterize the likelihood of a short-time abrupt change in the stock prices. Actual data from the São Paulo Stock Exchange (Bolsa de Valores de São Paulo) were used in this work to illustrate the proposed method.

  19. Financing climate change adaptation.

    Science.gov (United States)

    Bouwer, Laurens M; Aerts, Jeroen C J H

    2006-03-01

    This paper examines the topic of financing adaptation in future climate change policies. A major question is whether adaptation in developing countries should be financed under the 1992 United Nations Framework Convention on Climate Change (UNFCCC), or whether funding should come from other sources. We present an overview of financial resources and propose the employment of a two-track approach: one track that attempts to secure climate change adaptation funding under the UNFCCC; and a second track that improves mainstreaming of climate risk management in development efforts. Developed countries would need to demonstrate much greater commitment to the funding of adaptation measures if the UNFCCC were to cover a substantial part of the costs. The mainstreaming of climate change adaptation could follow a risk management path, particularly in relation to disaster risk reduction. 'Climate-proofing' of development projects that currently do not consider climate and weather risks could improve their sustainability.

  20. Final Scientific Report for "The Interhemispheric Pattern in 20th Century and Future Abrupt Change in Regional Tropical Rainfall"

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, John C. H. [University of California, Berkeley, CA (United States); Wehner, Michael F. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-10-29

    This is the final scientific report for grant DOE-FG02-08ER64588, "The Interhemispheric Pattern in 20th Century and Future Abrupt Change in Regional Tropical Rainfall."The project investigates the role of the interhemispheric pattern in surface temperature – i.e. the contrast between the northern and southern temperature changes – in driving rapid changes to tropical rainfall changes over the 20th century and future climates. Previous observational and modeling studies have shown that the tropical rainband – the Intertropical Convergence Zone (ITCZ) over marine regions, and the summer monsoonal rainfall over land – are sensitive to the interhemispheric thermal contrast; but that the link between the two has not been applied to interpreting long-term tropical rainfall changes over the 20th century and future.The specific goals of the project were to i) develop dynamical mechanisms to explain the link between the interhemispheric pattern to abrupt changes of West African and Asian monsoonal rainfall; ii) Undertake a formal detection and attribution study on the interhemispheric pattern in 20th century climate; and iii) assess the likelihood of changes to this pattern in the future. In line with these goals, our project has produced the following significant results: 1.We have developed a case that suggests that the well-known abrupt weakening of the West African monsoon in the late 1960s was part of a wider co-ordinated weakening of the West African and Asian monsoons, and driven from an abrupt cooling in the high latitude North Atlantic sea surface temperature at the same time. Our modeling work suggests that the high-latitude North Atlantic cooling is effective in driving monsoonal weakening, through driving a cooling of the Northern hemisphere that is amplified by positive radiative feedbacks. 2.We have shown that anthropogenic sulfate aerosols may have partially contributed to driving a progressively southward displacement of the Atlantic Intertropical

  1. Chatham Islands Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Mullan, B.; Salinger, J.; Thompson, C.; Ramsay, D.; Wild, M.

    2005-06-15

    This brief report provides guidance on climate change specific to the Chatham Islands, to complement the information recently produced for local government by the Ministry for the Environment in 'Climate Change Effects and Impacts Assessment: A guidance manual for Local Government in New Zealand' and 'Coastal Hazards and Climate Change: A guidance manual for Local Government in New Zealand'. These previous reports contain a lot of generic information on climate change, and how to assess associated risks, that is relevant to the Chatham Islands Council.

  2. Climate Change in Prehistory

    Science.gov (United States)

    Burroughs, William James

    2005-06-01

    How did humankind deal with the extreme challenges of the last Ice Age? How have the relatively benign post-Ice Age conditions affected the evolution and spread of humanity across the globe? By setting our genetic history in the context of climate change during prehistory, the origin of many features of our modern world are identified and presented in this illuminating book. It reviews the aspects of our physiology and intellectual development that have been influenced by climatic factors, and how features of our lives - diet, language and the domestication of animals - are also the product of the climate in which we evolved. In short: climate change in prehistory has in many ways made us what we are today. Climate Change in Prehistory weaves together studies of the climate with anthropological, archaeological and historical studies, and will fascinate all those interested in the effects of climate on human development and history.

  3. Ocean surface conditions on the SE Greenland shelf during the last millennium - from abrupt changes to centennial variability

    Science.gov (United States)

    Miettinen, Arto; Divine, Dmitry; Husum, Katrine; Koç, Nalan; Jennings, Anne

    2016-04-01

    August sea surface temperatures (aSST) and April sea-ice concentrations (aSIC) covering the last 2900 years have been reconstructed in order to investigate the variability of summer surface conditions along possible forcing factors on the SE Greenland shelf. In this diatom-based study, we focus on the interval ca. 870-1910 Common Era (CE) reconstructed at a high temporal resolution of 3-8 years. The results demonstrate both abrupt changes and a clear centennial-bicentennial variability for the last millennium. The Medieval Climate Anomaly (MCA) between 1000 and 1200 CE represents the warmest ocean surface conditions of the SE Greenland shelf over the late Holocene (880 BCE-1910 CE). MCA in the current record is characterized by abrupt, decadal to multidecadal changes, such as an abrupt warming of ~2.4 °C in 55 years around 1000 CE. Temperature changes of these magnitudes are rarely observed in other proxy records from the North Atlantic. Compared to regional air temperature reconstructions, our results indicate a lag of about 50 years in ocean surface warming either due to increased freshwater discharge from the Greenland ice sheet or intensified sea-ice export from the Arctic as a response to atmospheric warming at the beginning of the MCA. A cool phase, from 1200-1890 CE, associated with the Little Ice Age (LIA), ends with the rapid warming of aSST and diminished aSIC in the early 20th century. The phases of warm aSST and aSIC minima on the SE Greenland shelf and solar minima of the last millennium are antiphased, suggesting that solar forcing possibly amplified by atmospheric forcing has been behind the aSST variability on the SE Greenland over the last millennium. The results might indicate decreased sea ice formation on the SE Greenland shelf due to diminished freshwater input from the Greenland Ice Sheet during the cold climate periods. The results show that the SE Greenland shelf is a climatologically sensitive area where extremely rapid changes are

  4. Climate Change and Roads

    DEFF Research Database (Denmark)

    Chinowsky, P.; Arndt, Channing

    2012-01-01

    Decision-makers who are responsible for determining when and where infrastructure should be developed and/or enhanced are facing a new challenge with the emerging topic of climate change. The paper introduces a stressor–response methodology where engineering-based models are used as a basis...... four climate projection scenarios, the paper details how climate change response decisions may cost the Mozambican government in terms of maintenance costs and long-term roadstock inventory reduction. Through this approach the paper details how a 14% reduction in inventory loss can be achieved through...... the adoption of a proactive, design standard evolution approach to climate change....

  5. The magnitude, timing and abruptness of changes in North African dust deposition over the last 20,000 yr

    Science.gov (United States)

    McGee, D.; deMenocal, P. B.; Winckler, G.; Stuut, J. B. W.; Bradtmiller, L. I.

    2013-06-01

    Reconstructions of eolian dust accumulation in northwest African margin sediments provide important continuous records of past changes in atmospheric circulation and aridity in the region. Existing records indicate dramatic changes in North African dust emissions over the last 20 ka, but the limited spatial extent of these records and the lack of high-resolution flux data do not allow us to determine whether changes in dust deposition occurred with similar timing, magnitude and abruptness throughout northwest Africa. Here we present new records from a meridional transect of cores stretching from 31°N to 19°N along the northwest African margin. By combining grain size endmember modeling with 230Th-normalized fluxes for the first time, we are able to document spatial and temporal changes in dust deposition under the North African dust plume throughout the last 20 ka. Our results provide quantitative estimates of the magnitude of dust flux changes associated with Heinrich Stadial 1, the Younger Dryas, and the African Humid Period (AHP; ˜11.7-5 ka), offering robust targets for model-based estimates of the climatic and biogeochemical impacts of past changes in North African dust emissions. Our data suggest that dust fluxes between 8 and 6 ka were a factor of ˜5 lower than average fluxes during the last 2 ka. Using a simple model to estimate the effects of bioturbation on dust input signals, we find that our data are consistent with abrupt, synchronous changes in dust fluxes in all cores at the beginning and end of the AHP. The mean ages of these transitions are 11.8±0.2 ka (1σ) and 4.9±0.2 ka, respectively.

  6. Climate Change Crunch Time

    Institute of Scientific and Technical Information of China (English)

    Xie Zhenhua

    2011-01-01

    CLIMATE change is a severe challenge facing humanity in the 21st century and thus the Chinese Government always attaches great importance to the problem.Actively dealing with climate change is China's important strategic policy in its social and economic development.China will make a positive contribution to the world in this regard.

  7. Climate Change Dossier

    NARCIS (Netherlands)

    Albers, R.A.W.

    2010-01-01

    Climate change is one of the great issues of our time. It is a complex, multi-facetted issue concerning flooding, energy efficiency, CO2 storage and sustainable energy, among others. TNO is actively involved in the issue, undertaking many studies relating to various aspects. The climate is changing;

  8. Climate Change and Vietnam

    Science.gov (United States)

    2013-11-01

    expansion of large hydropower and reservoir construction can increase social resilience through associated economic development . However, the same...of the most vulnerable countries globally to the consequences of climate change, Vietnam is highly likely to experience a variety of negative...iii ABSTRACT Climate Change and Vietnam As one of the most vulnerable countries globally to the consequences

  9. Abrupt change of Antarctic moisture origin at the end of Termination II

    Science.gov (United States)

    Masson-Delmotte, V.; Stenni, B.; Blunier, T.; Cattani, O.; Chappellaz, J.; Cheng, H.; Dreyfus, G.; Edwards, R. L.; Falourd, S.; Govin, A.; Kawamura, K.; Johnsen, S. J.; Jouzel, J.; Landais, A.; Lemieux-Dudon, B.; Lourantou, A.; Marshall, G.; Minster, B.; Mudelsee, M.; Pol, K.; Röthlisberger, R.; Selmo, E.; Waelbroeck, C.

    2010-01-01

    The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C East Antarctic ice core provide new insights on the sequence of events involved in Termination II, the transition between the penultimate glacial and interglacial periods. This termination is marked by a north–south seesaw behavior, with first a slow methane concentration rise associated with a strong Antarctic temperature warming and a slow deuterium excess rise. This first step is followed by an abrupt north Atlantic warming, an abrupt resumption of the East Asian summer monsoon, a sharp methane rise, and a CO2 overshoot, which coincide within dating uncertainties with the end of Antarctic optimum. Here, we show that this second phase is marked by a very sharp Dome C centennial deuterium excess rise, revealing abrupt reorganization of atmospheric circulation in the southern Indian Ocean sector. PMID:20566887

  10. Liquid concentration distribution and planar interface instability at an abruptly changing pulling velocity in directional solidification

    Institute of Scientific and Technical Information of China (English)

    LI ShuangMing; FU HengZhi

    2007-01-01

    Liquid concentration distribution is seriously affected by an abruptly changing pulling velocity under directional solidification. Theoretical and numerical investigations indicate that at the pulling velocity jumping from V0 to V, the solidification system does not achieve the pulling velocity V immediately, and it goes through a non-steady-state transition zone. As the pulling velocity abruptly increases (V/V0 > 1), interface liquid concentration firstly increases to the maximum and then decreases to the steady-state value. The magnitude of interface liquid concentration at the beginning increases with V/V0, the initial pulling velocity V0 and the temperature gradient GL in the liquid. At the same time, solute diffusion length reduces with V/V0 and GL. In contrast, the minimum of interface liquid concentration falls with V/V0 at the pulling velocity decreasing abruptly. As the interface liquid concentration enriched at V/V0 > 1 is more than the value required for the planar interface to keep stable, the solid/liquid interface may become unstable. The analytical results are in agreement with the numerical calculation results of Al-2%Cu alloy.

  11. Liquid concentration distribution and planar interface instability at an abruptly changing pulling velocity in directional solidification

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Liquid concentration distribution is seriously affected by an abruptly changing pulling velocity under directional solidification. Theoretical and numerical investi-gations indicate that at the pulling velocity jumping from V0 to V, the solidification system does not achieve the pulling velocity V immediately, and it goes through a non-steady-state transition zone. As the pulling velocity abruptly increases (V/V0 > 1), interface liquid concentration firstly increases to the maximum and then de-creases to the steady-state value. The magnitude of interface liquid concentration at the beginning increases with V/V0, the initial pulling velocity V0 and the tem-perature gradient GL in the liquid. At the same time, solute diffusion length reduces with V/V0 and GL. In contrast, the minimum of interface liquid concentration falls with V/V0 at the pulling velocity decreasing abruptly. As the interface liquid con-centration enriched at V/V0 > 1 is more than the value required for the planar inter-face to keep stable, the solid/liquid interface may become unstable. The analytical results are in agreement with the numerical calculation results of Al-2%Cu alloy.

  12. Observed Abrupt Changes in Minimum and Maximum Temperatures in Jordan in the 20th Century

    Directory of Open Access Journals (Sweden)

    Mohammad M.  samdi

    2006-01-01

    Full Text Available This study examines changes in annual and seasonal mean (minimum and maximum temperatures variations in Jordan during the 20th century. The analyses focus on the time series records at the Amman Airport Meteorological (AAM station. The occurrence of abrupt changes and trends were examined using cumulative sum charts (CUSUM and bootstrapping and the Mann-Kendall rank test. Statistically significant abrupt changes and trends have been detected. Major change points in the mean minimum (night-time and mean maximum (day-time temperatures occurred in 1957 and 1967, respectively. A minor change point in the annual mean maximum temperature also occurred in 1954, which is essential agreement with the detected change in minimum temperature. The analysis showed a significant warming trend after the years 1957 and 1967 for the minimum and maximum temperatures, respectively. The analysis of maximum temperatures shows a significant warming trend after the year 1967 for the summer season with a rate of temperature increase of 0.038°C/year. The analysis of minimum temperatures shows a significant warming trend after the year 1957 for all seasons. Temperature and rainfall data from other stations in the country have been considered and showed similar changes.

  13. Forecasting abrupt changes in foreign exchange markets: method using dynamical network marker

    Science.gov (United States)

    Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

    2014-11-01

    We apply the idea of dynamical network markers (Chen et al 2012 Sci. Rep. 2 342) to foreign exchange markets so that early warning signals can be provided for any abrupt changes. The dynamical network marker constructed achieves a high odds ratio for forecasting these sudden changes. In addition, we also extend the notion of the dynamical network marker by using recurrence plots so that the notion can be applied to delay coordinates and point processes. Thus, the dynamical network marker is useful in a variety of contexts in science, technology, and society.

  14. Detecting Abrupt Changes in the Spectra of High-Energy Astrophysical Sources

    CERN Document Server

    Wong, Raymond K W; Lee, Thomas C M; van Dyk, David A

    2015-01-01

    Variable-intensity astronomical sources are the result of complex and often extreme physical processes. Abrupt changes in source intensity are typically accompanied by equally sudden spectral shifts, i.e., sudden changes in the wavelength distribution of the emission. This article develops a method for modeling photon counts collected form observation of such sources. We embed change points into a marked Poisson process, where photon wavelengths are regarded as marks and both the Poisson intensity parameter and the distribution of the marks are allowed to change. We believe this is the first effort to embed change points into a marked Poisson process. Between the change points, the spectrum is modeled non-parametrically using a mixture of a smooth radial basis expansion and a number of local deviations from the smooth term representing spectral emission lines. Because the model is over parameterized we employ an $\\ell_1$ penalty. The tuning parameter in the penalty and the number of change points are determin...

  15. Asking about climate change

    DEFF Research Database (Denmark)

    Nielsen, Jonas Østergaard; D'haen, Sarah Ann Lise

    2014-01-01

    and on vulnerability and adaptation strategies in a particular region or community. But how do we research the ways in which people experience changing climatic conditions, the processes of decision-making, the actual adaptation strategies carried out and the consequences of these for actors living and dealing...... with climate change? On the basis of a literature review of all articles published in Global Environmental Change between 2000 and 2012 that deal with human dimensions of climate change using qualitative methods this paper provides some answers but also raises some concerns. The period and length of fieldwork...

  16. Communities under climate change

    DEFF Research Database (Denmark)

    Nogues, David Bravo; Rahbek, Carsten

    2011-01-01

    The distribution of species on Earth and the interactions among them are tightly linked to historical and contemporary climate, so that global climate change will transform the world in which we live. Biological models can now credibly link recent decadal trends in field data to climate change......, but predicting future impacts on biological communities is a major challenge. Attempts to move beyond general macroecological predictions of climate change impact on one hand, and observations from specific, local-scale cases, small-scale experiments, or studies of a few species on the other, raise a plethora...... of unanswered questions. On page 1124 of this issue, Harley (1) reports results that cast new light on how biodiversity, across different trophic levels, responds to climate change....

  17. Cuba confronts climate change.

    Science.gov (United States)

    Alonso, Gisela; Clark, Ismael

    2015-04-01

    Among environmental problems, climate change presents the greatest challenges to developing countries, especially island nations. Changes in climate and the resulting effects on human health call for examination of the interactions between environmental and social factors. Important in Cuba's case are soil conditions, food availability, disease burden, ecological changes, extreme weather events, water quality and rising sea levels, all in conjunction with a range of social, cultural, economic and demographic conditions.

  18. Abrupt Holocene changes of the Asian monsoon at millen-nial- and centennial-scales:Evidence from lake sediment document in Minqin Basin,NW China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Considerable research is now focusing on abrupt Holocene changes at millennial- and centennial-scales all over the world. This study shows that the changes in the Holocene summer monsoon can be divided into two main periods, based on climatic proxy records of lake sediments from the Sanjiaocheng section located at the NW boundary of the summer monsoon, Gansu Province. The early and middle Holocene was humid with stronger summer monsoon, while the late Holocene is dry with weak summer monsoon. Detailed results also show a series of millennial- and centennial-scale changes in the intensity of the summer monsoon, with a periodicity of 1600 years during the whole Holocene, and with a periodicity of 800 years during the early Holocene. Ten dry events during the Holocene are associated with the weakening of the summer monsoon. These rapid climatic changes may be representative of a global climatic change pattern during the Holocene.

  19. Global climate change and international security.

    Energy Technology Data Exchange (ETDEWEB)

    Karas, Thomas H.

    2003-11-01

    This report originates in a workshop held at Sandia National Laboratories, bringing together a variety of external experts with Sandia personnel to discuss 'The Implications of Global Climate Change for International Security.' Whatever the future of the current global warming trend, paleoclimatic history shows that climate change happens, sometimes abruptly. These changes can severely impact human water supplies, agriculture, migration patterns, infrastructure, financial flows, disease prevalence, and economic activity. Those impacts, in turn, can lead to national or international security problems stemming from aggravation of internal conflicts, increased poverty and inequality, exacerbation of existing international conflicts, diversion of national and international resources from international security programs (military or non-military), contribution to global economic decline or collapse, or international realignments based on climate change mitigation policies. After reviewing these potential problems, the report concludes with a brief listing of some research, technology, and policy measures that might mitigate them.

  20. Changes in extreme regional sea surface height due to an abrupt weakening of the Atlantic MOC

    Directory of Open Access Journals (Sweden)

    S.-E. Brunnabend

    2014-04-01

    Full Text Available As an extreme scenario of dynamical sea level changes, regional sea surface height (SSH changes that occur in the North Atlantic due to an abrupt weakening of the Atlantic Meridional Overturning Circulation (AMOC are simulated. Two versions of the same ocean-only model are used to study the effect of ocean model resolution on these SSH changes: a high-resolution (HR strongly eddying version and a low-resolution (LR version in which the effect of eddies are parameterized. The weakening of the AMOC is induced in both model versions by applying strong freshwater perturbations around Greenland. A rapid decrease of the AMOC in the HR version induces much shorter return times of several specific regional and coastal extremes in North Atlantic SSH than in the LR version. This effect is caused by a change in main eddy pathways associated with a change in separation latitude of the Gulf Stream.

  1. Climate change and skin.

    Science.gov (United States)

    Balato, N; Ayala, F; Megna, M; Balato, A; Patruno, C

    2013-02-01

    Global climate appears to be changing at an unprecedented rate. Climate change can be caused by several factors that include variations in solar radiation received by earth, oceanic processes (such as oceanic circulation), plate tectonics, and volcanic eruptions, as well as human-induced alterations of the natural world. Many human activities, such as the use of fossil fuel and the consequent accumulation of greenhouse gases in the atmosphere, land consumption, deforestation, industrial processes, as well as some agriculture practices are contributing to global climate change. Indeed, many authors have reported on the current trend towards global warming (average surface temperature has augmented by 0.6 °C over the past 100 years), decreased precipitation, atmospheric humidity changes, and global rise in extreme climatic events. The magnitude and cause of these changes and their impact on human activity have become important matters of debate worldwide, representing climate change as one of the greatest challenges of the modern age. Although many articles have been written based on observations and various predictive models of how climate change could affect social, economic and health systems, only few studies exist about the effects of this change on skin physiology and diseases. However, the skin is the most exposed organ to environment; therefore, cutaneous diseases are inclined to have a high sensitivity to climate. For example, global warming, deforestation and changes in precipitation have been linked to variations in the geographical distribution of vectors of some infectious diseases (leishmaniasis, lyme disease, etc) by changing their spread, whereas warm and humid environment can also encourage the colonization of the skin by bacteria and fungi. The present review focuses on the wide and complex relationship between climate change and dermatology, showing the numerous factors that are contributing to modify the incidence and the clinical pattern of many

  2. Climate change and compensation

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint; Flanagan, Tine Bech

    2013-01-01

    This paper presents a case for compensation of actual harm from climate change in the poorest countries. First, it is shown that climate change threatens to reverse the fight to eradicate poverty. Secondly, it is shown how the problems raised in the literature for compensation to some extent...... climate change. The first argument appeals to the principle that if it is an injustice to cause risk of incurring harm in the future, then it is also an injustice to cause a similar harm now. The second argument appeals to the principle that if there is moral reason to reduce the risk of specific harms...

  3. Climate change governance

    Energy Technology Data Exchange (ETDEWEB)

    Knieling, Joerg [HafenCity Univ. Hamburg (Germany). Urban Planning and Regional Development; Leal Filho, Walter (eds.) [HAW Hamburg (Germany). Research and Transfer Centre Applications of Life Science

    2013-07-01

    Climate change is a cause for concern both globally and locally. In order for it to be tackled holistically, its governance is an important topic needing scientific and practical consideration. Climate change governance is an emerging area, and one which is closely related to state and public administrative systems and the behaviour of private actors, including the business sector, as well as the civil society and non-governmental organisations. Questions of climate change governance deal both with mitigation and adaptation whilst at the same time trying to devise effective ways of managing the consequences of these measures across the different sectors. Many books have been produced on general matters related to climate change, such as climate modelling, temperature variations, sea level rise, but, to date, very few publications have addressed the political, economic and social elements of climate change and their links with governance. This book will address this gap. Furthermore, a particular feature of this book is that it not only presents different perspectives on climate change governance, but it also introduces theoretical approaches and brings these together with practical examples which show how main principles may be implemented in practice.

  4. Adapting to climate change

    DEFF Research Database (Denmark)

    Arndt, Channing; Strzepek, Kenneth; Tarp, Finn

    2011-01-01

    Mozambique, like many African countries, is already highly susceptible to climate variability and extreme weather events. Climate change threatens to heighten this vulnerability. In order to evaluate potential impacts and adaptation options for Mozambique, we develop an integrated modeling...... framework that translates atmospheric changes from general circulation model projections into biophysical outcomes via detailed hydrologic, crop, hydropower and infrastructure models. These sector models simulate a historical baseline and four extreme climate change scenarios. Sector results are then passed...... down to a dynamic computable general equilibrium model, which is used to estimate economy-wide impacts on national welfare, as well as the total cost of damages caused by climate change. Potential damages without changes in policy are significant; our discounted estimates range from US2.3 to US2.3toUS7...

  5. Olivine and climate change

    NARCIS (Netherlands)

    Schuiling, R.D.

    2012-01-01

    The greenhouse effect, thanks mainly to the water vapor in our atmosphere, has created a livable climate on Earth. Climate change, however, may potentially have dire consequences. It is generally assumed that the rise in CO2 levels in the atmosphere is the main culprit, although several other

  6. Olivine and climate change

    NARCIS (Netherlands)

    Schuiling, R.D.

    2012-01-01

    The greenhouse effect, thanks mainly to the water vapor in our atmosphere, has created a livable climate on Earth. Climate change, however, may potentially have dire consequences. It is generally assumed that the rise in CO2 levels in the atmosphere is the main culprit, although several other greenh

  7. Climate change and compensation

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint; Flanagan, Tine Bech

    2013-01-01

    This paper presents a case for compensation of actual harm from climate change in the poorest countries. First, it is shown that climate change threatens to reverse the fight to eradicate poverty. Secondly, it is shown how the problems raised in the literature for compensation to some extent...... are based on misconceptions and do not apply to compensation of present actual harm. Finally, two arguments are presented to the effect that, in so far as developed countries accept a major commitment to mitigate climate change, they should also accept a commitment to address or compensate actual harm from...... climate change. The first argument appeals to the principle that if it is an injustice to cause risk of incurring harm in the future, then it is also an injustice to cause a similar harm now. The second argument appeals to the principle that if there is moral reason to reduce the risk of specific harms...

  8. Criminality and climate change

    Science.gov (United States)

    White, Rob

    2016-08-01

    The impacts of climate change imply a reconceptualization of environment-related criminality. Criminology can offer insight into the definitions and dynamics of this behaviour, and outline potential areas of redress.

  9. Population and Climate Change

    Science.gov (United States)

    O'Neill, Brian C.; Landis MacKellar, F.; Lutz, Wolfgang

    2000-11-01

    Population and Climate Change provides the first systematic in-depth treatment of links between two major themes of the 21st century: population growth (and associated demographic trends such as aging) and climate change. It is written by a multidisciplinary team of authors from the International Institute for Applied Systems Analysis who integrate both natural science and social science perspectives in a way that is comprehensible to members of both communities. The book will be of primary interest to researchers in the fields of climate change, demography, and economics. It will also be useful to policy-makers and NGOs dealing with issues of population dynamics and climate change, and to teachers and students in courses such as environmental studies, demography, climatology, economics, earth systems science, and international relations.

  10. Climate Change Adaptation Training

    Science.gov (United States)

    A list of on-line training modules to help local government officials and those interested in water management issues better understand how the changing climate affects the services and resources they care about

  11. Climate Change Adaptation

    DEFF Research Database (Denmark)

    Hudecz, Adriána

    -operation and research into the common problems of the Northern Periphery. This report is an output of the ROADEX “Implementing Accessibility” project (2009-2012). It gives a summary of the results of research into adaptation measures to combat climate change effects on low volume roads in the Northern Periphery....... The research was carried out between January 2000 and March 2012. One of the biggest challenges that mankind has to face is the prospect of climate change resulting from emissions of greenhouse gases. These gases trap energy in the atmosphere and cause global surface temperatures to rise. This warming in turn...... causes changes in other climatic variables such as rainfall, humidity and wind speed that impact on the functioning of infrastructure such road networks. This paper discusses the climate changes predicted by the world’s meteorological organisations and considers how these may impact on the public...

  12. Climate change and forest diseases

    Science.gov (United States)

    R.N. Sturrock; Susan Frankel; A. V. Brown; Paul Hennon; J. T. Kliejunas; K. J. Lewis; J. J. Worrall; A. J. Woods

    2011-01-01

    As climate changes, the effects of forest diseases on forest ecosystems will change. We review knowledge of relationships between climate variables and several forest diseases, as well as current evidence of how climate, host and pathogen interactions are responding or might respond to climate change. Many forests can be managed to both adapt to climate change and...

  13. Abrupt climate variability of eastern Anatolia vegetation during the last glacial

    Directory of Open Access Journals (Sweden)

    N. Pickarski

    2015-07-01

    Full Text Available Detailed analyses of the Lake Van pollen and stable oxygen isotope record allow the identification of millennial-scale vegetation and environmental changes in eastern Anatolia throughout the last glacial. The climate within the last glacial period (∼75–15 ka BP was cold and dry, with low arboreal pollen (AP levels. The driest and coldest period corresponds to Marine Isotope Stage (MIS 2 (∼28–14.5 ka BP dominated by the highest values of xerophytic steppe vegetation. Our high-resolution multi proxy record shows rapid expansions and contractions that mimic the stadial-interstadial pattern of the Dansgaard–Oeschger (DO events as recorded in the Greenland ice cores, and thus, provide a linkage to North Atlantic climate oscillations. Periods of reduced moisture availability characterized at Lake Van by enhanced xerophytic species correlates well with increase in ice-rafted debris (IRD and a decrease of sea surface temperature (SST in the North Atlantic. Furthermore, comparison with the marine realm reveals that the complex atmosphere–ocean interaction can be recognized by the strength and position of the westerlies in eastern Anatolia. Influenced by rough topography at Lake Van, the expansion of temperate species (e.g. deciduous Quercus was stronger during interstadials DO 19, 17–16, 14, 12 and 8. However, Heinrich events (HE, characterized by highest concentrations of ice-rafted debris in marine sediments, are identified in eastern Anatolia by AP values not lower and high steppe components not more abundant than during DO stadials. In addition, this work is a first attempt to establish a continuous microscopic charcoal record over the last glacial in the Near East, which documents an initial immediate response to millennial-scale climate and environmental variability and enables the shed light on the history of fire activity during the last glacial.

  14. Climate change and cities

    Energy Technology Data Exchange (ETDEWEB)

    Satterthwaite, David

    2006-10-15

    What is done, or not done, in cities in relation to climate change over the next 5-10 years will affect hundreds of millions of people, because their lives and livelihoods are at risk from global warming. What is done in cities will also have a major influence on whether the escalating risks for the whole planet will be reduced or eliminated. Climate change needs to be considered in all development plans and investments - local, regional, national and international. Urban growth must be made more climate-resilient and help reduce, rather than increase, greenhouse gas emissions. This will not be done by the market; it can only be done by governments.

  15. GREEN ECONOMY AND CLIMATE CHANGE PREVENTION CYCLE

    Directory of Open Access Journals (Sweden)

    Andreea CONSTANTINESCU

    2014-12-01

    Full Text Available While experts in economics place transition to green economy on two directions - reducing ecological footprint and increasing human welfare - climate change specialists warn that effects of global warming will have a much greater impact in the future. It is natural to join scientific contributions in these two areas because both perspectives recognize the ravages made by industrialization, which triggered a serie of abrupt climate changes. For example, the average temperature in Europe has increased about 1oC. Based on these evidences, this article will show the usefulness of introducing a concept of full cycle to prevent climate change in the new paradigm that seeks to solve problems related to the fundamentals of sustainable development through transition to green economy. Using this method, this approach intends to be a new theoretical contribution which can act as support to efficiency of new clean technologies.

  16. Evolutionary rescue and adaptation to abrupt environmental change depends upon the history of stress.

    Science.gov (United States)

    Gonzalez, Andrew; Bell, Graham

    2013-01-19

    Whether evolution will be rapid enough to rescue declining populations will depend upon population size, the supply of genetic variation, the degree of maladaptation and the historical direction of selection. We examined whether the level of environmental stress experienced by a population prior to abrupt environmental change affects the probability of evolutionary rescue (ER). Hundreds of populations of two species of yeast, Saccharomyces cerevisiae and Saccharomyces paradoxus were exposed to a range of sublethal concentrations of salt for approximately a hundred generations before transfer to a concentration of salt lethal to the ancestor (150 g l(-1) NaCl). The fitness of surviving populations of both species was a quadratic function of yield: fitness was greatest for large populations that had been selected on low salt concentrations (less than 20 g l(-1) NaCl) and small populations that had adapted to high salt (more than 80 g l(-1) NaCl). However, differences occurred between species in the probability of ER. The frequency of ER was positively correlated with salt concentration for S. cerevisiae, but negatively correlated with salt concentration in S. paradoxus. These results not only demonstrate that past environmental conditions can determine the probability of ER after abrupt environmental change, but also suggest that there may even be differences between closely related species that are worth further exploration.

  17. A double window state observer for detection and isolation of abrupt changes in parameters

    Directory of Open Access Journals (Sweden)

    Byrski Jędrzej

    2016-09-01

    Full Text Available The paper presents a new method for diagnosis of a process fault which takes the form of an abrupt change in some real parameter of a time-continuous linear system. The abrupt fault in the process real parameter is reflected in step changes in many parameters of the input/output model as well as in step changes in canonical state variables of the system. Detection of these state changes will enable localization of the faulty parameter in the system. For detecting state changes, a special type of exact state observer will be used. The canonical state will be represented by the derivatives of the measured output signal. Hence the exact state observer will play the role of virtual sensors for reconstruction of the derivatives of the output signal. For designing the exact state observer, the model parameters before and after the moment of fault occurrence must be known. To this end, a special identification method with modulating functions will be used. A novel concept presented in this paper concerns the structure of the observer. It will take the form of a double moving window observer which consists of two signal processing windows, each of width T. These windows are coupled to each other with a common edge. The right-hand side edge of the left-side moving window in the interval [t − 2T, t − T ] is connected to the left-hand side edge of the right-side window which operates in the interval [t − T, t]. The double observer uses different measurements of input/output signals in both the windows, and for each current time t simultaneously reconstructs two values of the state—the final value of the state in the left-side window zT (t − T and the initial value of the state z0(t − T in the right-side window. If the process parameters are constant, the values of both the states on the common joint edge are the same. If an abrupt change (fault in some parameter at the moment tA = t − T occurs in the system, then step changes in some

  18. Offspring loss after male change in wild siamangs: the importance of abrupt weaning and male care.

    Science.gov (United States)

    Morino, Luca; Borries, Carola

    2017-01-01

    Infanticide by males is assumed to promote permanent male-female associations, although its importance for social monogamy is still debated. We examined the consequences of male membership change in the largest socially monogamous primate, the siamang (Symphalangus syndactylus), a species that also forms polyandrous groups and where males may provide offspring care. We examine (a) the potential risk of infanticide by documenting changes in female-offspring relationships following male change, expecting abrupt weaning; and (b) the potential importance of male care and polyandry for offspring survival. We witnessed four male changes at Way Canguk Field Station (Indonesia) in groups where the youngest offspring was estimated to be about 2 years of age. We quantified aspects of mother-offspring relationships (interindividual distance, body contact, and nipple contact) and estimated the proportion of time being carried during travel (August 2007-April 2009). In the two groups into which new males immigrated, offspring were weaned abruptly, suggesting infanticide by males as a potential risk. Even though no attacks on infants by males were witnessed, both infants disappeared shortly after the male change. Another infant disappeared after its main carrier (a male) emigrated. Conversely, in a group where the resident subordinate male replaced the dominant male, the offspring experienced no change in care and survived the transition. These findings suggest that male immigration in hylobatids increases mortality risk for infants, emphasize the importance of offspring care, and cast doubts on prior classifications of 2-year-old siamangs as independently traveling individuals. © 2016 Wiley Periodicals, Inc.

  19. Abrupt millennial variability and interdecadal-interstadial oscillations in a global coupled model: sensitivity to the background climate state

    Energy Technology Data Exchange (ETDEWEB)

    Arzel, Olivier [The University of New South Wales, Climate Change Research Centre (CCRC), Sydney (Australia); Universite de Bretagne Occidentale, Laboratoire de Physique des Oceans (LPO), Brest (France); England, Matthew H. [The University of New South Wales, Climate Change Research Centre (CCRC), Sydney (Australia); Verdiere, Alain Colin de; Huck, Thierry [Universite de Bretagne Occidentale, Laboratoire de Physique des Oceans (LPO), Brest (France)

    2012-07-15

    The origin and bifurcation structure of abrupt millennial-scale climate transitions under steady external solar forcing and in the absence of atmospheric synoptic variability is studied by means of a global coupled model of intermediate complexity. We show that the origin of Dansgaard-Oeschger type oscillations in the model is caused by the weaker northward oceanic heat transport in the Atlantic basin. This is in agreement with previous studies realized with much simpler models, based on highly idealized geometries and simplified physics. The existence of abrupt millennial-scale climate transitions during glacial times can therefore be interpreted as a consequence of the weakening of the negative temperature-advection feedback. This is confirmed through a series of numerical experiments designed to explore the sensitivity of the bifurcation structure of the Atlantic meridional overturning circulation to increased atmospheric CO{sub 2} levels under glacial boundary conditions. Contrasting with the cold, stadial, phases of millennial oscillations, we also show the emergence of strong interdecadal variability in the North Atlantic sector during warm interstadials. The instability driving these interdecadal-interstadial oscillations is shown to be identical to that found in ocean-only models forced by fixed surface buoyancy fluxes, that is, a large-scale baroclinic instability developing in the vicinity of the western boundary current in the North Atlantic. Comparisons with modern observations further suggest a physical mechanism similar to that driving the 30-40 years time scale associated with the Atlantic multidecadal oscillation. (orig.)

  20. Meteorological hazard assessment based on trends and abrupt changes in rainfall characteristics on the Korean peninsula

    Science.gov (United States)

    Sung, Jang Hyun; Chung, Eun-Sung; Kim, Yeonjoo; Lee, Bo-Ram

    2017-01-01

    This study presents a statistical approach for assessing meteorological hazards based on trends and abrupt changes in precipitation characteristics. Daily rainfall data from 64 stations in South Korea (SK) and 27 stations in North Korea (NK) were used to identify temporal patterns in the rainfall characteristics of both regions using seven rainfall indices, such as the total annual rainfall and annual number of wet days. This study suggests the use of three steps in identifying meteorological hazards based on two statistical analyses. In step 1, we conducted a trend analysis of a 10-year moving average of the rainfall index using the Mann-Kendall (MK) trend test. Most stations (65.6 %) in SK exhibit clear increasing trends in five indices, whereas far fewer have data indicating any trends in five of the indices in NK (25.9 %). In step 2, abrupt changes in all rainfall indices were identified using a Bayesian Change Point (BCP) approach. The results contradict those from the MK trend analysis. The proportion of stations in NK where trends were identified is much higher than that in SK. In step 3, the results from the two previous steps were integrated to identify the meteorological hazards based on the identified trend and change point. The BCP approach can be used to identify meteorological hazards that MK cannot, as the former approach focuses on the change point during the entire period. As a result, meteorological stability at the sites of weather stations can be identified, and then the meteorological hazards across the entire Korean peninsula can be spatially interpolated. Although SK and NK are located on the same peninsula, distinct differences in the trends were observed.

  1. Fisheries portfolio diversification and turnover buffer Alaskan fishing communities from abrupt resource and market changes

    Science.gov (United States)

    Cline, Timothy J.; Schindler, Daniel E.; Hilborn, Ray

    2017-01-01

    Abrupt shifts in natural resources and their markets are a ubiquitous challenge to human communities. Building resilient social-ecological systems requires approaches that are robust to uncertainty and to regime shifts. Harvesting diverse portfolios of natural resources and adapting portfolios in response to change could stabilize economies reliant on natural resources and their markets, both of which are prone to unpredictable shifts. Here we use fisheries catch and revenue data from Alaskan fishing communities over 34 years to test whether diversification and turnover in the composition of fishing opportunities increased economic stability during major ocean and market regime shifts in 1989. More than 85% of communities show reduced fishing revenues following these regime shifts. However, communities with the highest portfolio diversity and those that could opportunistically shift the composition of resources they harvest, experienced negligible or even positive changes in revenue. Maintaining diversity in economic opportunities and enabling turnover facilitates sustainability of communities reliant on renewable resources facing uncertain futures. PMID:28091534

  2. Fisheries portfolio diversification and turnover buffer Alaskan fishing communities from abrupt resource and market changes.

    Science.gov (United States)

    Cline, Timothy J; Schindler, Daniel E; Hilborn, Ray

    2017-01-16

    Abrupt shifts in natural resources and their markets are a ubiquitous challenge to human communities. Building resilient social-ecological systems requires approaches that are robust to uncertainty and to regime shifts. Harvesting diverse portfolios of natural resources and adapting portfolios in response to change could stabilize economies reliant on natural resources and their markets, both of which are prone to unpredictable shifts. Here we use fisheries catch and revenue data from Alaskan fishing communities over 34 years to test whether diversification and turnover in the composition of fishing opportunities increased economic stability during major ocean and market regime shifts in 1989. More than 85% of communities show reduced fishing revenues following these regime shifts. However, communities with the highest portfolio diversity and those that could opportunistically shift the composition of resources they harvest, experienced negligible or even positive changes in revenue. Maintaining diversity in economic opportunities and enabling turnover facilitates sustainability of communities reliant on renewable resources facing uncertain futures.

  3. Topologies of climate change

    DEFF Research Database (Denmark)

    Blok, Anders

    2010-01-01

    Climate change is quickly becoming a ubiquitous socionatural reality, mediating extremes of sociospatial scale from the bodily to the planetary. Although environmentalism invites us to ‘think globally and act locally', the meaning of these scalar designations remains ambiguous. This paper explores...... the topological presuppositions of social theory in the context of global climate change, asking how carbon emissions ‘translate' into various sociomaterial forms. Staging a meeting between Tim Ingold's phenomenology of globes and spheres and the social topologies of actor-network theory (ANT), the paper advances...... a ‘relational-scalar' analytics of spatial practices, technoscience, and power. As technoscience gradually constructs a networked global climate, this ‘grey box' comes to circulate within fluid social spaces, taking on new shades as it hybridizes knowledges, symbols, and practices. Global climates thus come...

  4. Poverty and Climate Change

    Science.gov (United States)

    van der Vink, G.; Franco, E.; Fuckar, N. S.; Kalmbach, E. R.; Kayatta, E.; Lankester, K.; Rothschild, R. E.; Sarma, A.; Wall, M. L.

    2008-05-01

    The poor are disproportionately vulnerable to environmental change because they have the least amount of resources with which to adapt, and they live in areas (e.g. flood plains, low-lying coastal areas, and marginal drylands) that are particularly vulnerable to the manifestations of climate change. By quantifying the various environmental, economic, and social factors that can contribute to poverty, we identify populations that are most vulnerable to poverty and poverty traps due to environmental change. We define vulnerability as consisting of risk (probability of event and exposed elements), resiliency, and capacity to respond. Resiliency captures the social system's ability to absorb a natural disaster while retaining the same basic structure, organization, and ways of functioning, as well as its general capacity to adapt to stress and change. Capacity to respond is a surrogate for technical skills, institutional capabilities, and efficacy within countries and their economies. We use a "climate change multiplier" to account for possible increases in the frequency and severity of natural events due to climate change. Through various analytical methods, we quantify the social, political, economic, and environmental factors that contribute to poverty or poverty traps. These data sets are then used to determine vulnerability through raster multiplication in geospatial analysis. The vulnerability of a particular location to climate change is then mapped, with areas of high vulnerability clearly delineated. The success of this methodology indicates that it is indeed possible to quantify the effects of climate change on global vulnerability to natural disasters, and can be used as a mechanism to identify areas where proactive measures, such as improving adaptation or capacity to respond, can reduce the humanitarian and economic impacts of climate change.

  5. Managing climate change refugia for climate adaptation

    Science.gov (United States)

    Toni Lyn Morelli; Christopher Daly; Solomon Z. Dobrowski; Deanna M. Dulen; Joseph L. Ebersole; Stephen T. Jackson; Jessica D. Lundquist; Connie Millar; Sean P. Maher; William B. Monahan; Koren R. Nydick; Kelly T. Redmond; Sarah C. Sawyer; Sarah Stock; Steven R. Beissinger

    2016-01-01

    Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that...

  6. Preview of Our Changing Planet. The U.S. Climate Change Science Program for Fiscal Year 2008

    Science.gov (United States)

    2007-04-01

    in their future projections. A recent study has used a simple model to attempt to reproduce paleoclimate reconstructions of Northern Hemisphere...and oceanic ecosystems. Abrupt Changes in a Warming Climate – Paleoclimate research indicates that major shifts in regional and global climate have...FY 2008 will emphasize (1) model experiments designed to test potential mechanisms for abrupt change, and (2) paleoclimate research on patterns

  7. Evaporation and Climate Change

    NARCIS (Netherlands)

    Brandsma, T.

    1993-01-01

    In this article the influence of climate change on evaporation is discussed. The emphasis is on open water evaporation. Three methods for calculating evaporation are compared considering only changes in temperature and factors directly dependent on temperature. The Penman-method is used to

  8. Evaporation and Climate Change

    NARCIS (Netherlands)

    Brandsma, T.

    1993-01-01

    In this article the influence of climate change on evaporation is discussed. The emphasis is on open water evaporation. Three methods for calculating evaporation are compared considering only changes in temperature and factors directly dependent on temperature. The Penman-method is used to investiga

  9. Climate Change: Good for Us?

    Science.gov (United States)

    Oblak, Jackie

    2000-01-01

    Presents an activity with the objective of encouraging students to think about the effects of climate change. Explains background information on dependence to climate and discuses whether climate change is important. Provides information for the activity, extensions, and evaluation. (YDS)

  10. Managing Climate Change Refugia for Climate Adaptation

    Science.gov (United States)

    The concept of refugia has long been studied from theoretical and paleontological perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change ref...

  11. Managing Climate Change Refugia for Climate Adaptation

    Science.gov (United States)

    The concept of refugia has long been studied from theoretical and paleontological perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change ref...

  12. Climate change matters.

    Science.gov (United States)

    Macpherson, Cheryl Cox

    2014-04-01

    One manifestation of climate change is the increasingly severe extreme weather that causes injury, illness and death through heat stress, air pollution, infectious disease and other means. Leading health organisations around the world are responding to the related water and food shortages and volatility of energy and agriculture prices that threaten health and health economics. Environmental and climate ethics highlight the associated challenges to human rights and distributive justice but rarely address health or encompass bioethical methods or analyses. Public health ethics and its broader umbrella, bioethics, remain relatively silent on climate change. Meanwhile global population growth creates more people who aspire to Western lifestyles and unrestrained socioeconomic growth. Fulfilling these aspirations generates more emissions; worsens climate change; and undermines virtues and values that engender appreciation of, and protections for, natural resources. Greater understanding of how virtues and values are evolving in different contexts, and the associated consequences, might nudge the individual and collective priorities that inform public policy toward embracing stewardship and responsibility for environmental resources necessary to health. Instead of neglecting climate change and related policy, public health ethics and bioethics should explore these issues; bring transparency to the tradeoffs that permit emissions to continue at current rates; and offer deeper understanding about what is at stake and what it means to live a good life in today's world.

  13. Abrupt Longitudinal Magnetic Field Changes and Ultraviolet Emissions Accompanying Solar Flares

    CERN Document Server

    Johnstone, Brittany; Sudol, Jeffrey; 10.1088/0004-637X/760/1/29

    2012-01-01

    We have used Transition Region and Coronal Explorer (TRACE) 1600 \\AA images and Global Oscillation Network Group (GONG) magnetograms to compare ultraviolet (UV) emissions from the chromosphere to longitudinal magnetic field changes in the photosphere during four X-class solar flares. An abrupt, significant, and persistent change in the magnetic field occurred across more than ten pixels in the GONG magnetograms for each flare. These magnetic changes lagged the GOES flare start times in all cases, showing that they were consequences and not causes of the flares. Ultraviolet emissions were spatially coincident with the field changes. The UV emissions tended to lag the GOES start times for the flares, and led the changes in the magnetic field in all pixels except one. The UV emissions led the photospheric field changes by 4 minutes on average with the longest lead being 9 minutes, however, the UV emissions continued for tens of minutes, and more than an hour in some cases, after the field changes were complete. ...

  14. Use of abrupt strain path change for determining subsequent yield surface

    DEFF Research Database (Denmark)

    Kuroda, Mitsutoshi; Tvergaard, Viggo

    1999-01-01

    is prescribed, which makes the stress point move quickly along the yield surface. It is assumed that a closed-loop testing machine is used for the experiment, so that the strain path can be prescribed according to strain gauge measurements. Relative to the standard method of determining yield surface shapes......For elastic-plastic materials, a new method is proposed for determining the shape of the subsequent yield surface in the Vicinity of a current loading point. A proportional strain path is prescribed until the loading point of interest has been reached, then an abrupt strain path change...... by probing in many different stress directions from the elastic region, using some chosen plastic strain offset, the main advantage of the proposed method is that elastic unloading is not needed prior to tracing the yield surface. The method is illustrated here by a few analyses, first for the simplest how...

  15. Climate Change and Future World

    Science.gov (United States)

    2013-03-01

    fresh water. Movements of migrants from northern Africa and the Middle-East are already a security problem for Europe . This phenomenon is likely to be...Climate Change Science Program , Climate Literacy – The Essential Principles of Climate Sciences, 3. (http://library.globalchange.gov/climate...06/2013. 21 U.S. Climate Change Science Program , Climate Literacy – The Essential Principles of Climate Sciences, 3. (http

  16. Use of calcareous algae and monensin in Nellore cattle subjected to an abrupt change in diet

    Directory of Open Access Journals (Sweden)

    Roberta Ferreira Carvalho

    2016-04-01

    Full Text Available ABSTRACT: Additives are used in high concentrate diets to prevent metabolic disorders in cattle. This study was designed to evaluate the effect of calcium sources and monensin on the control of ruminal acidosis in Nellore cattle that were abruptly shifted to a high (92.3% concentrate diet. Eight cannulated steers were randomly assigned to two contemporary 4x4 Latin square. Treatments involved the addition of a calcium source, either limestone (LI or a product derived from calcareous algae (CA, to the basic diet with or without the presence of monensin. Calcareous alga (Lithothamnium calcareum is a natural and renewable product and a source of calcium carbonate. The quantity of added limestone, calcareous algae and monensin was 7.1g kg-1, 7.4g kg-1 and 30mg kg-1 DM, respectively. There was no effect of calcium source (P=0.607 or monensin (P=0.294 on feed intake or on the concentration of short chain fatty acids. Treatments with calcareous algae resulted in a higher mean ruminal pH (P=0.039, a shorter amount of time with the ruminal pH under 5.2 (P<0.001 and a better control of blood pH (P=0.006. Treatments with monensin also resulted in a shorter amount of time with the ruminal pH below 5.2 (P=0.023. Calcareous algae were shown to be effective in controlling adverse changes in the rumen and in blood variables for Nellore cattle that were subjected to an abrupt change to a high concentrate diet.

  17. Climate change and amphibians

    Directory of Open Access Journals (Sweden)

    Corn, P. S.

    2005-01-01

    Full Text Available Amphibian life histories are exceedingly sensitive to temperature and precipitation, and there is good evidence that recent climate change has already resulted in a shift to breeding earlier in the year for some species. There are also suggestions that the recent increase in the occurrence of El Niño events has caused declines of anurans in Central America and is linked to elevated mortality of amphibian embryos in the northwestern United States. However, evidence linking amphibian declines in Central America to climate relies solely on correlations, and the mechanisms underlying the declines are not understood. Connections between embryo mortality and declines in abundance have not been demonstrated. Analyses of existing data have generally failed to find a link between climate and amphibian declines. It is likely, however, that future climate change will cause further declines of some amphibian species. Reduced soil moisture could reduce prey species and eliminate habitat. Reduced snowfall and increased summer evaporation could have dramatic effects on the duration or occurrence of seasonal wetlands, which are primary habitat for many species of amphibians. Climate change may be a relatively minor cause of current amphibian declines, but it may be the biggest future challenge to the persistence of many species

  18. [Climate change and pollination].

    Science.gov (United States)

    Besancenot, J-P; Thibaudon, M

    2012-12-01

    There is growing evidence to support an increase in air temperature over recent decades, with significant effects on aeroallergens such as pollen. It is generally accepted that the trend will continue, and become even more pronounced in the future. Global climate change is already affecting, and will continue to affect, with earlier floral initiation, the timing of the production of allergenic pollen. In addition, a warmer climate might lead to a longer pollen season and more days with high pollen counts. It could also increase the allergen content of pollens, and result in extension of plant species towards the poles and higher altitudes. Finally, rising levels of atmospheric CO₂ are likely to reinforce these trends. These predictions are subject to uncertainties that may lead to outcomes that differ materially from what is expected. Understanding the magnitude and direction of the changes affecting pollinisation is critical in order to quantify the future allergic disease burden and model the impacts of different climate change scenarios. Climate change influences the production, distribution, dispersion and allergenicity of anemophilous pollen and the growth and distribution of weeds, grasses and trees that produce it. These changes in aeroallergens and subsequent human exposure could affect the prevalence and severity of allergic disorders. There is, therefore, an important public health issue that requires development and implementation of appropriate response strategies without delay. © 2012 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  19. Energy and Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-06-15

    Climate change, and more specifically the carbon emissions from energy production and use, is one of the more vexing problems facing society today. The Intergovernmental Panel on Climate Change (IPCC) has just completed its latest assessment on the state of the science of climate change, on the potential consequences related to this change, and on the mitigation steps that could be implemented beginning now, particularly in the energy sector. Few people now doubt that anthropogenic climate change is real or that steps must be taken to deal with it. The World Energy Council has long recognized this serious concern and that in its role as the world's leading international energy organization, it can address the concerns of how to provide adequate energy for human well-being while sustaining our overall quality of life. It has now performed and published 15 reports and working papers on this subject. This report examines what has worked and what is likely to work in the future in this regard and provides policymakers with a practical roadmap to a low-carbon future and the steps needed to achieve it.

  20. Tackling Climate Change

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Representatives from nearly 200 countries and regions have gathered in Durban,South Africa,for the 17th session of the Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC) and the 7th session of the Meeting of the Parties to the Kyoto Protocol.The meeting is the follow-up conference to tacklin

  1. Turfgrass and climate change

    Science.gov (United States)

    Climate change is occurring and is manifesting its impact on biological systems through increased temperatures, precipitation, and carbon dioxide. These effects have been documented for a few agricultural species, primarily the grain crops and pasture and rangeland species. The extension of these re...

  2. Adaptation to climate change

    NARCIS (Netherlands)

    Carmin, J.; Tierney, K.; Chu, E.; Hunter, L.M.; Roberts, J.T.; Shi, L.; Dunlap, R.E.; Brulle, R.J.

    2015-01-01

    Climate change adaptation involves major global and societal challenges such as finding adequate and equitable adaptation funding and integrating adaptation and development programs. Current funding is insufficient. Debates between the Global North and South center on how best to allocate the financ

  3. Learning Progressions & Climate Change

    Science.gov (United States)

    Parker, Joyce M.; de los Santos, Elizabeth X.; Anderson, Charles W.

    2015-01-01

    Our society is currently having serious debates about sources of energy and global climate change. But do students (and the public) have the requisite knowledge to engage these issues as informed citizenry? The learning-progression research summarized here indicates that only 10% of high school students typically have a level of understanding…

  4. Corporate Climate Change

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The American Chamber of Commerce, the People's Republic of China (AmCham-China) and the American Chamber of Commerce in Shanghai recently released "American Corporate Experience in a Changing China: Insights From AmCham Business Climate Surveys, 1999-2005." Excerpts of the report follow:

  5. DTU Climate Change Technologies

    DEFF Research Database (Denmark)

    During 2008 and 2009, DTU held a workshop series focusing on assessment of and adaption to climate changes as well as on mitigation of green house gasses. In the workshops, a total of 1500 scientists, government officials and business leaders have outlined scenarios for technology development...

  6. Adaptation to climate change

    NARCIS (Netherlands)

    Carmin, J.; Tierney, K.; Chu, E.; Hunter, L.M.; Roberts, J.T.; Shi, L.; Dunlap, R.E.; Brulle, R.J.

    2015-01-01

    Climate change adaptation involves major global and societal challenges such as finding adequate and equitable adaptation funding and integrating adaptation and development programs. Current funding is insufficient. Debates between the Global North and South center on how best to allocate the

  7. Learning Progressions & Climate Change

    Science.gov (United States)

    Parker, Joyce M.; de los Santos, Elizabeth X.; Anderson, Charles W.

    2015-01-01

    Our society is currently having serious debates about sources of energy and global climate change. But do students (and the public) have the requisite knowledge to engage these issues as informed citizenry? The learning-progression research summarized here indicates that only 10% of high school students typically have a level of understanding…

  8. Changing Climate, Changing Behavior: Adaptive Economic Behavior and Housing Markets Responses to Flood Risks

    NARCIS (Netherlands)

    Filatova, Tatiana; Bin, Okmyung; Kaminski, Bogumil; Koloch, Grzegorz

    2014-01-01

    Spatial econometrics and analytical spatial economic modeling advanced significantly in the recent years. Yet, methodologically they are designed to tackle marginal changes in the underlying dynamics of spatial urban systems. In the world with climate change, however, abrupt sudden non-marginal chan

  9. Hantaviruses and climate change.

    Science.gov (United States)

    Klempa, B

    2009-06-01

    Most hantaviruses are rodent-borne emerging viruses. They cause two significant human diseases, haemorrhagic fever with renal syndrome in Asia and Europe, and hantavirus cardiopulmonary syndrome in the Americas. Very recently, several novel hantaviruses with unknown pathogenic potential have been identified in Africa and in a variety of insectivores (shrews and a mole). Because there is very limited information available on the possible impact of climate change on all of these highly dangerous pathogens, it is timely to review this aspect of their epidemiology. It can reasonably be concluded that climate change should influence hantaviruses through impacts on the hantavirus reservoir host populations. We can anticipate changes in the size and frequency of hantavirus outbreaks, the spectrum of hantavirus species and geographical distribution (mediated by changes in population densities), and species composition and geographical distribution of their reservoir hosts. The early effects of global warming have already been observed in different geographical areas of Europe. Elevated average temperatures in West-Central Europe have been associated with more frequent Puumala hantavirus outbreaks, through high seed production (mast year) and high bank vole densities. On the other hand, warm winters in Scandinavia have led to a decline in vole populations as a result of the missing protective snow cover. Additional effects can be caused by increased intensity and frequency of extreme climatic events, or by changes in human behaviour leading to higher risk of human virus exposure. Regardless of the extent of climate change, it is difficult to predict the impact on hantavirus survival, emergence and epidemiology. Nevertheless, hantaviruses will undoubtedly remain a significant public health threat for several decades to come.

  10. Teaching Climate Change

    Science.gov (United States)

    O'Donoghue, A.

    2011-09-01

    In giving public presentations about climate change, we face the barriers of mis-information in the political debate and lack of science literacy that extends to science phobia for some. In climate issues, the later problem is compounded by the fact that the science - reconstruction of past climate through the use of proxy sources, such as isotopes of oxygen and hydrogen - is complex, making it more challenging for general audiences. Also, the process of science, particularly peer review, is suspected by some to be a way of keeping science orthodox instead of keeping it honest. I approach these barriers by focusing on the data and the fact that the data have been carefully acquired over decades and centuries by dedicated people with no political agenda. I have taught elderhostel courses twice and have given many public talks on this topic. Thus I have experience in this area to share with others. I would also like to learn of others' approaches to the vast amount of scientific information and getting past the politics. A special interest group on climate change will allow those of us to speak on this important topic to share how we approach both the science and the politics of this issue.

  11. The Nonlinear Response of the Equatorial Pacific Ocean-Atmosphere System to Periodic Variations in Insolation and its Association with the Abrupt Climate Transitions during the Quaternary.

    Science.gov (United States)

    Lopes, P. G.

    2015-12-01

    The evidences of climate changes during the Quaternary are abundant but the physical mechanisms behind the climate transitions are controversial. The theory of Milankovitch takes into account the periodic orbital variations and the solar radiation received by the Earth as the main explanation for the glacial-interglacial cycles. However, some gaps in the theory still remain. In this study, we propose elucidating some of these gaps by approaching the Equatorial Pacific Ocean as a large oscillator, capable of triggering climate changes in different temporal scales. A mathematical model representing El Ninõ-like phenomena, based on Duffing equation and modulated by the astronomical cycle of 100 ka, was used to simulate the variability of the equatorial Pacific climate system over the last 2 Ma. The physical configuration of the Pacific Ocean, expressed in the equation, explains the temporal limit of the glacial-interglacial cycles. According to the simulation results, consistent with paleoclimate records, the amplification of the effects of the gradual variation of the Earth's orbit eccentricity - another unclear question - is due to the feedback mechanism of the Pacific ocean-atmosphere system, which responds non-linearly to small variations in insolation forcing and determines the ENSO-like phase (warm or cold) at different time scales and different intensities. The approach proposed here takes into account that the abrupt transitions between the ENSO-like phases, and the consequent changes in the sea surface temperature (SST) along the Equatorial Pacific Ocean, produce reactions that act as secondary causes of the temperature fluctuations that result in a glaciation (or deglaciation) - as the drastic change on the rate of evaporation/precipitation around the globe, and the increase (or decrease) of the atmospheric CO2 absorption by the phytoplankton. The transitional behavior between the warm and the cold phases, according to the presented model, is enhanced as

  12. Macrosegregation in Al-7Si alloy caused by abrupt cross-section change during directional solidification

    Science.gov (United States)

    Ghods, M.; Johnson, L.; Lauer, M.; Grugel, R. N.; Tewari, S. N.; Poirier, D. R.

    2016-09-01

    Hypoeutectic Al-7 wt .% Si alloys were directionally solidified vertically downward in cylindrical molds that incorporated an abrupt cross-section decrease (9.5 mm to 3.2 mm diameter) which, after 5 cm, reverted back to 9.5 mm diameter in a Bridgman furnace; two constant growth speeds and thermal gradients were investigated. Thermosolutal convection and cross-section-change-induced shrinkage flow effects on macrosegregation were investigated. Dendrite clustering and extensive radial macrosegregation was seen, particularly in the larger cross-sections, before contraction and after expansion, this more evident at the lower growth speed. This alloy shows positive longitudinal macrosegregation near cross-section decrease followed by negative macrosegregation right after it; the extent of macrosegregation, however, decreases with increasing growth speed. Primary dendrite steepling intensified as solidification proceeded into the narrower section and negative longitudinal macrosegregation was seen on the re-entrant shelves at expansion. A two-dimensional model accounting for both shrinkage and thermo-solutal convection was used to simulate solidification and the resulting mushy-zone steepling and macrosegregation. The experimentally observed longitudinal and radial macrosegregation associated with the cross-section changes during directional solidification of an Al-7Si alloy is well captured by the numerical simulations.

  13. Climate Change Justice

    OpenAIRE

    Sunstein, Cass R.; Posner, Eric A.

    2007-01-01

    Greenhouse gas reductions would cost some nations much more than others and benefit some nations far less than others. Significant reductions would impose especially large costs on the United States, and recent projections suggest that the United States has relatively less to lose from climate change. In these circumstances, what does justice require the United States to do? Many people believe that the United States is required to reduce its greenhouse gas emissions beyond the point that is ...

  14. Confronting Climate Change

    Science.gov (United States)

    Mintzer, Irving M.

    1992-06-01

    This book, which was published in time for the Earth Summit in Brazil in June 1992, is likely to make a huge impact on the political and economic agendas of international policy makers. It summarizes the scientific findings of Working Group I of the IPCC in the first part of the book. While acknowledging the uncertainties in subsequent chapters, it challenges and expands upon the existing views on how we should tackle the problems of climate change.

  15. Abrupt climate transition of icy worlds from snowball to moist or runaway greenhouse

    Science.gov (United States)

    Yang, Jun; Ding, Feng; Ramirez, Ramses M.; Peltier, W. R.; Hu, Yongyun; Liu, Yonggang

    2017-08-01

    Ongoing and future space missions aim to identify potentially habitable planets in our Solar System and beyond. Planetary habitability is determined not only by a planet's current stellar insolation and atmospheric properties, but also by the evolutionary history of its climate. It has been suggested that icy planets and moons become habitable after their initial ice shield melts as their host stars brighten. Here we show from global climate model simulations that a habitable state is not achieved in the climatic evolution of those icy planets and moons that possess an inactive carbonate-silicate cycle and low concentrations of greenhouse gases. Examples for such planetary bodies are the icy moons Europa and Enceladus, and certain icy exoplanets orbiting G and F stars. We find that the stellar fluxes that are required to overcome a planet's initial snowball state are so large that they lead to significant water loss and preclude a habitable planet. Specifically, they exceed the moist greenhouse limit, at which water vapour accumulates at high altitudes where it can readily escape, or the runaway greenhouse limit, at which the strength of the greenhouse increases until the oceans boil away. We suggest that some icy planetary bodies may transition directly to a moist or runaway greenhouse without passing through a habitable Earth-like state.

  16. Managing Climate Change Risks

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R. [CSIRO Atmospheric Research, PMB1 Aspendale, Victoria 3195 (Australia)

    2003-07-01

    Issues of uncertainty, scale and delay between action and response mean that 'dangerous' climate change is best managed within a risk assessment framework that evolves as new information is gathered. Risk can be broadly defined as the combination of likelihood and consequence; the latter measured as vulnerability to greenhouse-induced climate change. The most robust way to assess climate change damages in a probabilistic framework is as the likelihood of critical threshold exceedance. Because vulnerability is dominated by local factors, global vulnerability is the aggregation of many local impacts being forced beyond their coping ranges. Several case studies, generic sea level rise and temperature, coral bleaching on the Great Barrier Reef and water supply in an Australian catchment, are used to show how local risk assessments can be assessed then expressed as a function of global warming. Impacts treated thus can be aggregated to assess global risks consistent with Article 2 of the UNFCCC. A 'proof of concept' example is then used to show how the stabilisation of greenhouse gases can constrain the likelihood of exceeding critical thresholds at both the both local and global scale. This analysis suggests that even if the costs of reducing greenhouse gas emissions and the benefits of avoiding climate damages can be estimated, the likelihood of being able to meet a cost-benefit target is limited by both physical and socio-economic uncertainties. In terms of managing climate change risks, adaptation will be most effective at reducing vulnerability likely to occur at low levels of warming. Successive efforts to mitigate greenhouse gases will reduce the likelihood of reaching levels of global warming from the top down, with the highest potential temperatures being avoided first, irrespective of contributing scientific uncertainties. This implies that the first cuts in emissions will always produce the largest economic benefits in terms of avoided

  17. Climate change and disaster management.

    Science.gov (United States)

    O'Brien, Geoff; O'Keefe, Phil; Rose, Joanne; Wisner, Ben

    2006-03-01

    Climate change, although a natural phenomenon, is accelerated by human activities. Disaster policy response to climate change is dependent on a number of factors, such as readiness to accept the reality of climate change, institutions and capacity, as well as willingness to embed climate change risk assessment and management in development strategies. These conditions do not yet exist universally. A focus that neglects to enhance capacity-building and resilience as a prerequisite for managing climate change risks will, in all likelihood, do little to reduce vulnerability to those risks. Reducing vulnerability is a key aspect of reducing climate change risk. To do so requires a new approach to climate change risk and a change in institutional structures and relationships. A focus on development that neglects to enhance governance and resilience as a prerequisite for managing climate change risks will, in all likelihood, do little to reduce vulnerability to those risks.

  18. Abrupt along-strike change in tectonic style: San Andreas Fault zone, San Francisco Peninsula

    Science.gov (United States)

    Zoback, Mary Lou; Jachens, Robert C.; Olson, Jean A.

    1999-05-01

    Seismicity and high-resolution aeromagnetic data are used to define an abrupt change from compressional to extensional tectonism within a 10- to 15-km-wide zone along the San Andreas fault on the San Francisco Peninsula and offshore from the Golden Gate. This 100-km-long section of the San Andreas fault includes the hypocenter of the Mw = 7.8 1906 San Francisco earthquake as well as the highest level of persistent microseismicity along that ˜470-km-long rupture. We define two distinct zones of deformation along this stretch of the fault using well-constrained relocations of all post-1969 earthquakes based a joint one-dimensional velocity/hypocenter inversion and a redetermination of focal mechanisms. The southern zone is characterized by thrust- and reverse-faulting focal mechanisms with NE trending P axes that indicate "fault-normal" compression in 7- to 10-km-wide zones of deformation on both sides of the San Andreas fault. A 1- to 2-km-wide vertical zone beneath the surface trace of the San Andreas is characterized by its almost complete lack of seismicity. The compressional deformation is consistent with the young, high topography of the Santa Cruz Mountains/Coast Ranges as the San Andreas fault makes a broad restraining left bend (˜10°) through the southernmost peninsula. A zone of seismic quiescence ˜15 km long separates this compressional zone to the south from a zone of combined normal-faulting and strike-slip-faulting focal mechanisms (including a ML = 5.3 earthquake in 1957) on the northernmost peninsula and offshore on the Golden Gate platform. Both linear pseudogravity gradients, calculated from the aeromagnetic data, and seismic reflection data indicate that the San Andreas fault makes an abrupt ˜3-km right step less than 5 km offshore in this northern zone. A similar right-stepping (dilatational) geometry is also observed for the subparallel San Gregorio fault offshore. Persistent seismicity and extensional tectonism occur within the San Andreas

  19. Abrupt climate fluctuations in the tropics: the influence of Atlantic Ocean circulation

    Science.gov (United States)

    Street-Perrott, F. Alayne; Perrott, R. Alan

    1990-02-01

    Several prolonged droughts in the Sahel and tropical Mexico during the past 14,000 years were coincident with large injections of fresh water into the northern North Atlantic Ocean. The link between these phenomena lies in the thermohaline circulation of the oceans: input of fresh water decreases salinity leading to reduced North Atlantic Deep Water formation and anomalies of sea surface temperature of the kind associated with decreased rainfall in the northern tropics. Ice-sheet disintegration, the most important source of fresh-water input to the oceans, should therefore be considered explicitly in models of past and future climate.

  20. Strategy for Climate Change Adaptation

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    The absence of a global agreement on the reduction of greenhouse gas emissions calls for adaptation to climate change. The associated paper explains the need for climate change adaptation of the building stock and suggests a pattern for a strategic approach to how to reach the climate change...... adaptation needed. Issues that must be addressed in case a strategic approach is not developed, as the building sector is continuously investing in measures to adapt to climate change as impacts emerge are described....

  1. Climate change regional review: Russia

    OpenAIRE

    Sharmina, Maria; Anderson, Kevin; Bows-Larkin, Alice

    2013-01-01

    With climate change, an increasingly important focus of scientific and policy discourse, the Russian government has aimed to position the country as one of the leaders of the global process for addressing climate change. This article reviews a breadth of literature to analyze the politico-economic situation in Russia with regard to international climate change negotiations, related domestic policies, societal attitudes, and climatic change impacts on Russia's territory. The analysis demonstra...

  2. Interdecadal Variations of Precipitation and Temperature in China Around the Abrupt Change of Atmospheric Circulation in 1976

    Institute of Scientific and Technical Information of China (English)

    LI Chunhui; WAN Qilin; LIN Ailan; GU Dejun; ZHENG Bin

    2009-01-01

    The interdecadal characteristics of rainfall and temperature in China before and after the abrupt change of the general circulation in 1976 are analyzed using the global 2.5°×2.5° monthly mean reanalysis data from the National Centers for Environmental Prediction of US and the precipitation and temperature data at the 743 stations of China from the National Climate Center of China. The results show that after 1976, springtime precipitation and temperature were anomalously enhanced and reduced respectively in South China, while the reverse was true in the western Yangtze River basin. In summer, precipitation was anomalously less in South China, more in the Yangtze River basin, less again in North China and more again in Northeast China, showing a distribution pattern alternating with negative and positive anomalies ("-, +, -, +"). Meanwhile, temperature shows a distribution of warming in South China, cooling in the Yangtze and Huaihe River basins, and warming again in northern China. In autumn, precipitation tended to decrease and temperature tended to increase in most parts of the country. In winter, precipitation increased moderately in South China and warming was the trend across all parts of China. The interdecadal decline of mean temperature in spring and summer in China was mainly due to the daily maximum temperature variation, while the interdecadal increase was mainly the result of the minimum temperature change. The overall warming in autumn (winter) was mostly influenced by the minimum (maximum) temperature variation. These changes were closely related to the north-south shifts of the ascending and descending branches of the Hadley cell, the strengthening and north-south progression of the westerly jet stream, and the atmospheric stratification and water vapor transport conditions.

  3. The magnitude, timing and abruptness of changes in North African dust deposition over the last 20,000 yr

    OpenAIRE

    2013-01-01

    Reconstructions of eolian dust accumulation in northwest African margin sediments provide important continuous records of past changes in atmospheric circulation and aridity in the region. Existing records indicate dramatic changes in North African dust emissions over the last 20 ka, but the limited spatial extent of these records and the lack of high-resolution flux data do not allow us to determine whether changes in dust deposition occurred with similar timing, magnitude and abruptness thr...

  4. Climate Change and Natural Disasters

    NARCIS (Netherlands)

    Merkouris, Panos; Negri, Stefania; Maljean-Dubois, Sandrine

    2014-01-01

    Only 21 years ago, in 1992, the first ever convention on climate change, the United Nations Framework Convention on Climate Change (UNFCCC) was signed. The science behind studying climate change and its effects on the environment is not only mind-boggling but still in its infancy. It should come the

  5. Climate change and the biosphere

    Science.gov (United States)

    F. Stuart Chapin

    2008-01-01

    Scientific assessments now clearly demonstrate the ecologic and societal consequences of human induced climate change, as detailed by the most recent Intergovernmental Panel on Climate Change (IPCC) report. Global warming spells danger for Earth's biomes, which in turn play an important role in climate change. On the following pages, you will read about some of...

  6. Abrupt recent trend changes in atmospheric nitrogen dioxide over the Middle East

    KAUST Repository

    Lelieveld, J.

    2015-08-21

    Nitrogen oxides, released from fossil fuel use and other combustion processes, affect air quality and climate. From the mid-1990s onward, nitrogen dioxide (NO2) has been monitored from space, and since 2004 with relatively high spatial resolution by the Ozone Monitoring Instrument. Strong upward NO2 trends have been observed over South and East Asia and the Middle East, in particular over major cities. We show, however, that a combination of air quality control and political factors, including economical crisis and armed conflict, has drastically altered the emission landscape of nitrogen oxides in the Middle East. Large changes, including trend reversals, have occurred since about 2010 that could not have been predicted and therefore are at odds with emission scenarios used in projections of air pollution and climate change in the early 21st century.

  7. Population and climate change.

    Science.gov (United States)

    Cohen, Joel E

    2010-06-01

    To review, the four broad dimensions of any complex human problem, including climate change, are the human population, economics, culture, and environment. These dimensions interact with one another in all directions and on many time-scales. From 2010 to 2050, the human population is likely to grow bigger, more slowly, older, and more urban. It is projected that by 2050 more than 2.6 billion people (almost 94% of global urban growth) will be added to the urban population in today's developing countries. That works out to 1.26 million additional urban people in today's developing countries every week from 2010 to 2050. Humans alter the climate by emitting greenhouse gases, by altering planetary albedo, and by altering atmospheric components. Between 1900 and 2000, humans' emissions of carbon into the atmosphere increased fifteenfold, while the numbers of people increased less than fourfold. Population growth alone, with constant rates of emissions per person, could not account for the increase in the carbon emissions to the atmosphere. The world economy grew sixteenfold in the twentieth century, accompanied by enormous increases in the burning of gas, oil, and coal. In the last quarter of the twentieth century, population grew much faster in developing countries than in high-income countries, and, compared with population growth, the growth of carbon emissions to the atmosphere was even faster in developing countries than in high-income countries. The ratio of emissions-to-population growth rates was 2.8 in developing countries compared with 1.6 in high-income countries. Emissions of CO2 and other greenhouse gases are influenced by the sizes and density of settlements, the sizes of households, and the ages of householders. Between 2010 and 2050, these demographic factors are anticipated to change substantially. Therefore demography will play a substantial role in the dynamics of climate changes. Climate changes affect many aspects of the living environment

  8. Grapevine phenology and climate change in Georgia

    Science.gov (United States)

    Cola, G.; Failla, O.; Maghradze, D.; Megrelidze, L.; Mariani, L.

    2016-10-01

    While the climate of Western Europe has been deeply affected by the abrupt climate change that took place in the late `1980s of the twentieth century, a similar signal is detected only few years later, in 1994, in Georgia. Grapevine phenology is deeply influenced by climate and this paper aimed to analyze how phenological timing changed before and after the climatic change of 1994. Availability of thermal resources in the two climatic phases for the five altitudinal belts in the 0-1250-m range was analyzed. A phenological dataset gathered in two experimental sites during the period 2012-2014, and a suitable thermal dataset was used to calibrate a phenological model based on the normal approach and able to describe BBCH phenological stages 61 (beginning of flowering), 71 (fruit set), and 81 (veraison). Calibration was performed for four relevant Georgian varieties (Mtsvane Kakhuri, Rkatsiteli, Ojaleshi, and Saperavi). The model validation was performed on an independent 3-year dataset gathered in Gorizia (Italy). Furthermore, in the case of variety Rkatsiteli, the model was applied to the 1974-2013 thermal time series in order to obtain phenological maps of the Georgian territory. Results show that after the climate change of 1994, Rkatsiteli showed an advance, more relevant at higher altitudes where the whole increase of thermal resource was effectively translated in phenological advance. For instance the average advance of veraison was 5.9 days for 250-500 m asl belt and 18.1 days for 750-1000 m asl). On the other hand, at lower altitudes, phenological advance was depleted by superoptimal temperatures. As a final result, some suggestions for the adaptation of viticultural practices to the current climatic phase are provided.

  9. Interdisciplinarity, Climate, and Change

    Science.gov (United States)

    Pulwarty, R. S.

    2016-12-01

    Interdisciplinarity has become synonymous with all things progressive about research and education. This is so not simply because of a philosophical belief in the heterogeneity of knowledge but because of the scientific and social complexities of problems of major concern. The increased demand for improved climate knowledge and information has increased pressure to support planning under changing rates of extremes event occurrence, is well-documented. The application of useful climate data, information and knowledge requires multiple networks and information services infrastructure that support planning and implementation. As widely quoted, Pasteur's quadrant is a label given to a class of scientific research methodologies that seeks fundamental understanding of scientific problems and, simultaneously, to benefit society-what Stokes called "use-inspired research". Innovation, in this context, has been defined as "the process by which individuals and organizations generate new ideas and put them into practice". A growing number of research institutes and programs have begun developing a cadre of professionals focused on integrating basic and applied research in areas such as climate risk assessment and adaptation. There are now several examples of where researchers and teams have crafted examples that include affected communities. In this presentation we will outline the lessons from several efforts including the PACE program, the RISAs, NIDIS, the Climate Services Information System and other interdisciplinary service-oriented efforts in which the author has been involved. Some early lessons include the need to: Recognize that key concerns of social innovation go beyond the projections of climate and other global changes to embrace multiple methods Continue to train scientists of all stripes of disciplinary norms, but higher education should also prepare students who plan to seek careers outside of academia by increasing flexibility in graduate training programs

  10. Strategy for Climate Change Adaptation

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2013-01-01

    . This absence of an agreement calls for adaptation to climate change. Emphasis should be put on buildings, as they play a vital economic and social role in society and are vulnerable to climate change. Therefore, the building stock deserves its own policy and implementation plans as well as tools that enable...... adequate and cost-efficient adaptation to climate change. This paper explains the need for climate change adaptation of the building stock and suggests a pattern for a strategic approach to how to reach the climate change adaptation needed. The suggested and presented need of a strategic approach is based...... on three main initiatives consisting of the need to examine the potential impacts of climate change on the building stock, the need to assess and develop a roadmap of current and future adaptation measures that can withstand the effects of climate change, and the need to engage relevant stakeholders...

  11. Strategy for Climate Change Adaptation

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2014-01-01

    . This absence of an agreement calls for adaptation to climate change. Emphasis should be put on buildings, as they play a vital economic and social role in society and are vulnerable to climate change. Therefore, the building stock deserves its own policy and implementation plans as well as tools that enable...... adequate and cost-efficient adaptation to climate change. This paper explains the need for climate change adaptation of the building stock and suggests a pattern for a strategic approach to how to reach the climate change adaptation needed. The suggested and presented need of a strategic approach is based...... on three main initiatives consisting of the need to examine the potential impacts of climate change on the building stock, the need to assess and develop a roadmap of current and future adaptation measures that can withstand the effects of climate change, and the need to engage relevant stakeholders...

  12. Climate Changes around the world

    Energy Technology Data Exchange (ETDEWEB)

    Kahl, J.

    2009-07-01

    This presentation addresses several important aspects of the climate changes that are occurring around the globe. the causes of climate change are first reviewed, with illustrations of orbital oscillations, the atmospheric greenhouse effect, and aerosol effects. Observed changes in climate are next reviewed, both thought many millenia and during the past century. Distinctions are made between global warming and regional changes in temperature and precipitation. Changes in the frequency of weather extremes, including heat waves and tropical storms, are also discussed. (Author)

  13. Politics of climate change belief

    Science.gov (United States)

    2017-01-01

    Donald Trump's actions during the election and his first weeks as US president-elect send a strong message about his belief in climate change, or lack thereof. However, these actions may reflect polarization of climate change beliefs, not climate mitigation behaviour.

  14. Communicating Climate Change (Invited)

    Science.gov (United States)

    Mann, M. E.

    2009-12-01

    I will discuss the various challenges scientists must confront in efforts to communicate the science and implications of climate change to the public. Among these challenges is the stiff headwind we must fight of a concerted disinformation effort designed to confuse the public about the nature of our scientific understanding of the problem and the reality of the underlying societal threat. We also must fight the legacy of the public’s perception of the scientist. That is to say, we must strive to communicate in plainspoken language that neither insults the intelligence of our audience, nor hopelessly loses them in jargon and science-speak. And through all of this, we must maintain our composure and good humor even in the face of what we might consider the vilest of tactics by our opposition. When it comes to how best to get our message out to the broader public, I don’t pretend to have all of the answers. But I will share some insights and anecdotes that I have accumulated over the course of my own efforts to inform the public about the reality of climate change and the potential threat that it represents.

  15. Climate change and health

    Energy Technology Data Exchange (ETDEWEB)

    Last, J.M. [Ottawa Univ., ON (Canada); Chiotti, Q.P. [Environment Canada, Ottawa, ON (Canada)

    2001-12-31

    Adverse effects such as heat-related illnesses are felt on human health as a result of climate change. Those effects can also be the increased frequency and severity of extreme weather resulting in injury and death, a wider array of insect vectors for diseases, as well as increased risk of allergic, food-borne and water-borne diseases. Coastal ecosystems are altered, sea levels are rising and millions of people will need to relocate in the next century as a result of global warming. Keeping disaster plans, maintaining epidemiological monitoring and surveillance, and issuing advisory messages concerning the risks to human health are some of the responses required from public health officials. The establishment of standards, the development of policies on food and nutrition and the defining of priorities for research are important aspects that must be kept in mind. The authors indicated that multidisciplinary approaches are better suited to find solutions to the challenges encountered due to climate change than the narrow methods used in the past. refs., 4 tabs.

  16. Abrupt rather than gradual hormonal changes induce postpartum blues-like behavior in rats

    NARCIS (Netherlands)

    Doornbos, Bennard; Fokkema, Dirk S.; Molhoek, Margo; Tanke, Marit A. C.; Postema, Folkert; Korf, Jakob

    2009-01-01

    Aims: Postpartum blues is thought to be related to hormonal events accompanying delivery. We investigated whether blues-like symptoms depend on the rate of the decline of hormones, by comparing the behavioral consequences of an abrupt versus a gradual decline of gonadal hormones in an animal model.

  17. Abrupt rather than gradual hormonal changes induce postpartum blues-like behavior in rats

    NARCIS (Netherlands)

    Doornbos, Bennard; Fokkema, Dirk S.; Molhoek, Margo; Tanke, Marit A. C.; Postema, Folkert; Korf, Jakob

    2009-01-01

    Aims: Postpartum blues is thought to be related to hormonal events accompanying delivery. We investigated whether blues-like symptoms depend on the rate of the decline of hormones, by comparing the behavioral consequences of an abrupt versus a gradual decline of gonadal hormones in an animal model.

  18. Climate Change and Water Tools

    Science.gov (United States)

    EPA tools and workbooks guide users to mitigate and adapt to climate change impacts. Various tools can help manage risks, others can visualize climate projections in maps. Included are comprehensive tool kits hosted by other federal agencies.

  19. Climate Change and Water Training

    Science.gov (United States)

    To take action on climate impacts, practitioners must understand how climate change will effect their region, and the country. Training provided here by EPA and partners allow users to better grasp the issues and make decisions based on current science.

  20. Climate Change and Poverty Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Simon

    2011-08-15

    Climate change will make it increasingly difficult to achieve and sustain development goals. This is largely because climate effects on poverty remain poorly understood, and poverty reduction strategies do not adequately support climate resilience. Ensuring effective development in the face of climate change requires action on six fronts: investing in a stronger climate and poverty evidence base; applying the learning about development effectiveness to how we address adaptation needs; supporting nationally derived, integrated policies and programmes; including the climate-vulnerable poor in developing strategies; and identifying how mitigation strategies can also reduce poverty and enable adaptation.

  1. Response of interior North America to abrupt climate oscillations in the North Atlantic region during the last deglaciation

    Science.gov (United States)

    Yu, Zicheng; Wright, H. E.

    2001-02-01

    Several broad-scale climatic oscillations during the last deglaciation are well documented in regions around the North Atlantic Ocean. This paper reviews empirical evidence for these deglacial climatic oscillations from non-coastal North America and discusses implications for testing climatic simulations and for understanding the cause and transmittal mechanisms. Paleoclimatic interpretation of oxygen-isotope records from several small sites in the eastern Great Lakes region indicates a classic deglacial climatic sequence that is comparable with records from Europe and Greenland. The climatic events as interpreted from Crawford Lake oxygen isotopes include the Bølling-Allerød (BOA) warming at ˜12,700 14C BP, a warm BOA at ˜12,500-10,920 14C BP, an intra-Allerød cold period shortly before 11,000 14C BP, a cold Younger Dryas (YD) climate reversal at 10,920-10,000 14C BP, the Holocene warming at 10,000 14C BP, a brief Preboreal Oscillation (PB) at 9650 14C BP, and an early-Holocene cold event at 7500 14C BP (8200 cal BP). Some of these events were also evident from changes in upland and aquatic vegetation and sediment lithology. The pronounced YD climatic reversal has been documented from pollen records along the ecotones at this time and from glacier readvances in the Great Lakes region. Along the Rocky Mountains from Alberta to Colorado, the YD event is indicated by alpine glacier advance and/or shift in timberline vegetation. In Minnesota and upper New York, early-Holocene climatic instability is also suggested by oxygen-isotope records and/or varve thickness. The regional variations in evidence for the YD and other events in North America suggest that climatic oscillations may have different expressions in paleo-records, depending on geographic location and characteristics of a particular site. The extent and magnitude of these climatic oscillations across North America suggest that these oscillations are an expression of climatic change that was probably

  2. Philosophy of climate science part I: observing climate change

    OpenAIRE

    Frigg, Roman; Thompson, Erica; Werndl, Charlotte

    2015-01-01

    This is the first of three parts of an introduction to the philosophy of climate science. In this first part about observing climate change, the topics of definitions of climate and climate change, data sets and data models, detection of climate change, and attribution of climate change will be discussed.

  3. Climate change and marine life

    DEFF Research Database (Denmark)

    Richardson, Anthony J.; Brown, Christopher J.; Brander, Keith

    2012-01-01

    A Marine Climate Impacts Workshop was held from 29 April to 3 May 2012 at the US National Center of Ecological Analysis and Synthesis in Santa Barbara. This workshop was the culmination of a series of six meetings over the past three years, which had brought together 25 experts in climate change...... ecology, analysis of large datasets, palaeontology, marine ecology and physical oceanography. Aims of these workshops were to produce a global synthesis of climate impacts on marine biota, to identify sensitive habitats and taxa, to inform the current Intergovernmental Panel on Climate Change (IPCC......) process, and to strengthen research into ecological impacts of climate change...

  4. New insights into the stratospheric and mesosphere-lower thermospheric ozone response to the abrupt changes in solar forcing

    Directory of Open Access Journals (Sweden)

    Karanam Kishore Kumar

    2011-06-01

    Full Text Available Using a unique set of satellite based observations of the vertical distribution of ozone during the recent annular solar eclipse of 15 January 2010, we demonstrate for the first time, a complete picture of the response of stratospheric ozone to abrupt changes in solar forcing. The stratospheric ozone decreased after the maximum obscuration of the Sun and then gradually increased with time. A dramatic increase in stratospheric ozone of up to 4 ppmv is observed 3 h after the maximum obscuration of the Sun. The present study also reports for the first time the mesosphere-lower thermospheric ozone response to solar eclipse. Thus it is envisaged that the present results will have important implications in understanding the ozone response to abrupt changes in solar forcing and time-scales involved in such response.

  5. Changing heathlands in a changing climate

    DEFF Research Database (Denmark)

    Ransijn, Johannes

    to climatic change, its recovery after disturbance is severely hampered by drought and a combination of drought and disturbance can cause a shift from dwarf shrub to grass dominance. Comparison of multiple European climate change experiments show that plant communities are more vulnerable to climate change...... during early successional stages where climatic change can lead to shifts in plant community composition. The impacts of climate change on plant communities is likely to depend more on short periods where plants are relatively vulnerable (like regeneration phases after disturbance) than on the longer...... periods between disturbances where established vegetation is relatively robust. We suggest that future climate change experiments deliberately include disturbances and focus more on life phases where plants are most vulnerable....

  6. Climate Change Mitigation A Balanced Approach to Climate Change

    CERN Document Server

    2012-01-01

    This book provides a fresh and innovative perspective on climate change policy. By emphasizing the multiple facets of climate policy, from mitigation to adaptation, from technological innovation and diffusion to governance issues, it contains a comprehensive overview of the economic and policy dimensions of the climate problem. The keyword of the book is balance. The book clarifies that climate change cannot be controlled by sacrificing economic growth and many other urgent global issues. At the same time, action to control climate change cannot be delayed, even though gradually implemented. Therefore, on the one hand climate policy becomes pervasive and affects all dimensions of international policy. On the other hand, climate policy cannot be too ambitious: a balanced approach between mitigation and adaptation, between economic growth and resource management, between short term development efforts and long term innovation investments, should be adopted. I recommend its reading. Carlo Carraro, President, Ca�...

  7. Shear Forces during Blast, Not Abrupt Changes in Pressure Alone, Generate Calcium Activity in Human Brain Cells

    Science.gov (United States)

    2012-06-29

    Shear Forces during Blast, Not Abrupt Changes in Pressure Alone, Generate Calcium Activity in Human Brain Cells Rea Ravin1, Paul S. Blank1,2, Alex...Brain Cells’’ by Rea Ravin, Paul S. Blank, Alex Steinkamp, Shay Rappaport, Nitay Ravin, Ludmila Bezrukov, Hugo Guerrero-Cazares, Alfredo Quinones...the local strain field. Journal of Neurotrauma 23: 1304–1319. 25. Shin HS, Kim HJ, Sim SJ, Jeon NL (2009) Shear stress effect on transfection of

  8. Preparing for climate change.

    Science.gov (United States)

    Holdgate, M

    1989-01-01

    There is a distinct probability that humankind is changing the climate and at the same time raising the sea level of the world. The most plausible projections we have now suggest a rise in mean world temperature of between 1 degree Celsius and 2 degrees Celsius by 2030--just 40 years hence. This is a bigger change in a smaller period than we know of in the experience of the earth's ecosystems and human societies. It implies that by 2030 the earth will be warmer than at any time in the past 120,000 years. In the same period, we are likely to see a rise of 15-30 centimeters in sea level, partly due to the melting of mountain glaciers and partly to the expansion of the warmer seas. This may not seem much--but it comes on top of the 12-centimeter rise in the past century and we should recall that over 1/2 the world's population lives in zones on or near coasts. A quarter meter rise in sea level could have drastic consequences for countries like the Maldives or the Netherlands, where much of the land lies below the 2-meter contour. The cause of climate change is known as the 'greenhouse effect'. Greenhouse glass has the property that it is transparent to radiation coming in from the sun, but holds back radiation to space from the warmed surfaces inside the greenhouse. Certain gases affect the atmosphere in the same way. There are 5 'greenhouse gases' and we have been roofing ourselves with them all: carbon dioxide concentrations in the atmosphere have increased 25% above preindustrial levels and are likely to double within a century, due to tropical forest clearance and especially to the burning of increasing quantities of coal and other fossil fuels; methane concentrations are now twice their preindustrial levels as a result of releases from agriculture; nitrous oxide has increased due to land clearance for agriculture, use of fertilizers, and fossil fuel combustion; ozone levels near the earth's surface have increased due mainly to pollution from motor vehicles; and

  9. Conflict in a changing climate

    Science.gov (United States)

    Carleton, T.; Hsiang, S. M.; Burke, M.

    2016-05-01

    A growing body of research illuminates the role that changes in climate have had on violent conflict and social instability in the recent past. Across a diversity of contexts, high temperatures and irregular rainfall have been causally linked to a range of conflict outcomes. These findings can be paired with climate model output to generate projections of the impact future climate change may have on conflicts such as crime and civil war. However, there are large degrees of uncertainty in such projections, arising from (i) the statistical uncertainty involved in regression analysis, (ii) divergent climate model predictions, and (iii) the unknown ability of human societies to adapt to future climate change. In this article, we review the empirical evidence of the climate-conflict relationship, provide insight into the likely extent and feasibility of adaptation to climate change as it pertains to human conflict, and discuss new methods that can be used to provide projections that capture these three sources of uncertainty.

  10. Effect of abruptly changing withdrawal rate on solidification microstructure in directionally solidified Al-4.5wt%Cu alloy

    Directory of Open Access Journals (Sweden)

    Yang Luyan

    2014-01-01

    Full Text Available Al-4.5wt.%Cu alloy has been directionally solidified at constant and abruptly changing withdrawal rates, respectively. The effects of the withdrawal rate on solidification microstructure, primary dendrite arm spacing (PDAS and liquid solute distribution in front of the solid-liquid interface were investigated. The experimental results for the PDAS at a constant withdrawal rate agree well with the values calculated by the Hunt, Trivedi and Hunt-Lu models. At an abrupt change in the withdrawal rate, the maximum to minimum ratio of the PDAS at a given solidification parameter, i.e. λ1max/λ1min, is more than 2, and the PDAS values are remarkably history-dependent. Further, the liquid-solute distribution curve based on theoretical calculation shows that the larger the initial withdrawal rate is, the smaller the minimum of liquid solute concentration in front of the solid-liquid interface is after the abrupt change in withdrawal rate.

  11. Vulnerability of freshwater fisheries and impacts of climate change in south Indian states economies

    Digital Repository Service at National Institute of Oceanography (India)

    Sannadurgappa, D.; Abitha, R.; Sukumaran, S.

    activities and especially fishing are often held responsible for these abrupt ecosystem shifts, the oceanic biosphere is now also experiencing rapid global climatic change. But all of this takes us only half way to an answer; predicting the impacts... are among the most vulnerable to climate change (McClanahan et al., 2008). While there is a growing body of case studies on the observed effects of climate change on the distribution and production of individual fisheries (Brander, 2007), it is difficult...

  12. Inter-hemispheric linkages in climate change: paleo-perspectives for future climate change

    Directory of Open Access Journals (Sweden)

    J. Shulmeister

    2006-02-01

    both inter-annual and seven year periodicities are present, with the inter-annual signal dominant. Paleo-data demonstrate that the relative importance of the two periodicities changes through time, with longer periodicities dominant in the early Holocene.

    3. The recognition of climate modulation of oscillatory systems by abrupt climate events: We examine the relationship of ENSO to an abrupt SH climate event, the Antarctic cold reversal (ACR, in the New Zealand region. We demonstrate that the onset of the ACR was associated with the apparent switching on of an ENSO signal in New Zealand. We infer that this related to enhanced zonal SW winds with the amplification of the pressure fields allowing an existing but weak ENSO signal to manifest itself. Teleconnections of this nature would be difficult to predict for future abrupt change as boundary conditions cannot readily be specified. Paleo-data are critical to predicting the teleconnections of future abrupt changes.

  13. The Y. D. and climate abrupt events in the early and middle Holocene: Stalagmite oxygen isotope record from Maolan, Guizhou, China

    Institute of Scientific and Technical Information of China (English)

    QIN Jiaming; YUAN Daoxian; CHENG Hai; LIN Yushi; ZHANG Meiliang; WANG Fuxing; R. L. Edwards; WANG Hua; RAN Jingcheng

    2005-01-01

    The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 45 cm to 193.6 cm of the upper part of D4 stalagmite from Dongguo Cave in Libo, Guizhou, by using system TIMS U-series dating and carbon and oxygen stable isotope analyses.The study indicates that the last cold event, the YD (Younger Dryas) event, of the last glacial period was apparently shown in D4 record, which started from 12.80 kaBP and ended in 11.58 kaBP, with a great range of drop in temperature. The end of the last glacial period was consistent with the termination I in oceanic isotope records and was with time limit of 11.3 kaBP. The three most distinct cold events in the early and middle Holocene occurred respectively in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop in temperature reaching 2-5℃. The climate abrupt events in thousand and hundred years scale recorded in stalagmite δ18O can be compared to those in GISP2 ice cores from Greenland in their happening time and the range of their lasting time. The cold events in 8.27 kaBP and 4.75 kaBP can also be compared to CC3 stalagmite records in Ireland, which indicate that climate changes of short range in China monsoon areas, western Europe and polar regions, have the same driving factor. This has a global significance. In addition, the trend of record curves in some time- stages is apparently different, which reflects probably the difference between environment in monsoon climate areas and in polar regions.

  14. Climate change and human health

    DEFF Research Database (Denmark)

    Warren, John A; Berner, James E; Curtis, Tine

    2005-01-01

    or degradation of permafrost. Climate change can result in damage to sanitation infrastructure resulting in the spread of disease or threatening a community's ability to maintain its economy, geographic location and cultural tradition, leading to mental stress. Through monitoring of some basic indicators...... communities can begin to develop a response to climate change. With this information, planners, engineers, health care professionals and governments can begin to develop approaches to address the challenges related to climate change....

  15. Adapting agriculture to climate change

    NARCIS (Netherlands)

    Howden, S.M.; Soussana, J.F.; Tubiello, F.N.; Chhetri, N.; Dunlop, M.; Meinke, H.B.

    2007-01-01

    The strong trends in climate change already evident, the likelihood of further changes occurring, and the increasing scale of potential climate impacts give urgency to addressing agricultural adaptation more coherently. There are many potential adaptation options available for marginal change of

  16. Adapting agriculture to climate change

    NARCIS (Netherlands)

    Howden, S.M.; Soussana, J.F.; Tubiello, F.N.; Chhetri, N.; Dunlop, M.; Meinke, H.B.

    2007-01-01

    The strong trends in climate change already evident, the likelihood of further changes occurring, and the increasing scale of potential climate impacts give urgency to addressing agricultural adaptation more coherently. There are many potential adaptation options available for marginal change of exi

  17. Floods in a changing climate

    Science.gov (United States)

    Theresa K. Andersen; Marshall J. Shepherd

    2013-01-01

    Atmospheric warming and associated hydrological changes have implications for regional flood intensity and frequency. Climate models and hydrological models have the ability to integrate various contributing factors and assess potential changes to hydrology at global to local scales through the century. This survey of floods in a changing climate reviews flood...

  18. Game-Changing Innovations: How Culture Can Change the Parameters of Its Own Evolution and Induce Abrupt Cultural Shifts.

    Science.gov (United States)

    Kolodny, Oren; Creanza, Nicole; Feldman, Marcus W

    2016-12-01

    One of the most puzzling features of the prehistoric record of hominid stone tools is its apparent punctuation: it consists of abrupt bursts of dramatic change that separate long periods of largely unchanging technology. Within each such period, small punctuated cultural modifications take place. Punctuation on multiple timescales and magnitudes is also found in cultural trajectories from historical times. To explain these sharp cultural bursts, researchers invoke such external factors as sudden environmental change, rapid cognitive or morphological change in the hominids that created the tools, or replacement of one species or population by another. Here we propose a dynamic model of cultural evolution that accommodates empirical observations: without invoking external factors, it gives rise to a pattern of rare, dramatic cultural bursts, interspersed by more frequent, smaller, punctuated cultural modifications. Our model includes interdependent innovation processes that occur at different rates. It also incorporates a realistic aspect of cultural evolution: cultural innovations, such as those that increase food availability or that affect cultural transmission, can change the parameters that affect cultural evolution, thereby altering the population's cultural dynamics and steady state. This steady state can be regarded as a cultural carrying capacity. These parameter-changing cultural innovations occur very rarely, but whenever one occurs, it triggers a dramatic shift towards a new cultural steady state. The smaller and more frequent punctuated cultural changes, on the other hand, are brought about by innovations that spur the invention of further, related, technology, and which occur regardless of whether the population is near its cultural steady state. Our model suggests that common interpretations of cultural shifts as evidence of biological change, for example the appearance of behaviorally modern humans, may be unwarranted.

  19. Cinematic climate change, a promising perspective on climate change communication.

    Science.gov (United States)

    Sakellari, Maria

    2015-10-01

    Previous research findings display that after having seen popular climate change films, people became more concerned, more motivated and more aware of climate change, but changes in behaviors were short-term. This article performs a meta-analysis of three popular climate change films, The Day after Tomorrow (2005), An Inconvenient Truth (2006), and The Age of Stupid (2009), drawing on research in social psychology, human agency, and media effect theory in order to formulate a rationale about how mass media communication shapes our everyday life experience. This article highlights the factors with which science blends in the reception of the three climate change films and expands the range of options considered in order to encourage people to engage in climate change mitigation actions.

  20. Sewer Systems and Climate Change

    OpenAIRE

    Brandsma, T.

    1993-01-01

    In this article the impact of climate change on the overflows of sewer systems is assessed. The emphasis is on the overflows of combined sewer systems. The purpose is twofold: first, to obtain a first-order estimate of the impact of climate change on overflows of sewer systems; and second, to obtain insight into the relevant meteorological variables that are important with respect to climate change. A reservoir model is used to assess the impact of climate change on several combinations of st...

  1. Climate@Home: Crowdsourcing Climate Change Research

    Science.gov (United States)

    Xu, C.; Yang, C.; Li, J.; Sun, M.; Bambacus, M.

    2011-12-01

    Climate change deeply impacts human wellbeing. Significant amounts of resources have been invested in building super-computers that are capable of running advanced climate models, which help scientists understand climate change mechanisms, and predict its trend. Although climate change influences all human beings, the general public is largely excluded from the research. On the other hand, scientists are eagerly seeking communication mediums for effectively enlightening the public on climate change and its consequences. The Climate@Home project is devoted to connect the two ends with an innovative solution: crowdsourcing climate computing to the general public by harvesting volunteered computing resources from the participants. A distributed web-based computing platform will be built to support climate computing, and the general public can 'plug-in' their personal computers to participate in the research. People contribute the spare computing power of their computers to run a computer model, which is used by scientists to predict climate change. Traditionally, only super-computers could handle such a large computing processing load. By orchestrating massive amounts of personal computers to perform atomized data processing tasks, investments on new super-computers, energy consumed by super-computers, and carbon release from super-computers are reduced. Meanwhile, the platform forms a social network of climate researchers and the general public, which may be leveraged to raise climate awareness among the participants. A portal is to be built as the gateway to the climate@home project. Three types of roles and the corresponding functionalities are designed and supported. The end users include the citizen participants, climate scientists, and project managers. Citizen participants connect their computing resources to the platform by downloading and installing a computing engine on their personal computers. Computer climate models are defined at the server side. Climate

  2. Climate change and human health

    DEFF Research Database (Denmark)

    Warren, John A; Berner, James E; Curtis, Tine

    2005-01-01

    In northern regions, climate change can include changes in precipitation magnitude and frequency, reductions in sea ice extent and thickness, and climate warming and cooling. These changes can increase the frequency and severity of storms, flooding, or erosion; other changes may include drought...... or degradation of permafrost. Climate change can result in damage to sanitation infrastructure resulting in the spread of disease or threatening a community's ability to maintain its economy, geographic location and cultural tradition, leading to mental stress. Through monitoring of some basic indicators...... communities can begin to develop a response to climate change. With this information, planners, engineers, health care professionals and governments can begin to develop approaches to address the challenges related to climate change....

  3. Observed climatic changes in Shanghai during 1873-2002

    Institute of Scientific and Technical Information of China (English)

    ZHANGQiang; CHENJiaqi; ZHANGZengxin

    2005-01-01

    Variation characteristics of temperature and precipitation in January and July and annual mean temperature and annual precipitation are analyzed with the help of cumulative anomalies,Mann-Kendall analysis and wavelet analysis. The research results indicate that January precipitation presents an increasing trend after 1990, wavelet analysis result suggests that this increasing trend will continue in the near future. The changes of July precipitation present different features. During 1900-1960, July precipitation is in a rising trend, but is in a declining trend after 1960. Wavelet analysis shows that this declining trend will go on in the near future. Temperature variations in Shanghai are in fluctuations with 2 to 3 temperature rising periods. Mann-Kendall analysis indicates that temperature variations have the obvious abrupt change time when compared with precipitation changes in Shanghai during the past 100 years. The abrupt change time of January temperature lies in 1985, and that of July temperature lies in 1931-1933 and annual mean temperature has the abrupt change time in 1923-1930. Except July precipitation, the precipitation in January, temperature in January, July and annual mean temperature, and annual precipitation are also in a rising trend in the near future. The research results in this paper may be meaningful for future further climatic changes of Shanghai and social mitigation of climatic disasters in the future.

  4. Climate change, conflict and health.

    Science.gov (United States)

    Bowles, Devin C; Butler, Colin D; Morisetti, Neil

    2015-10-01

    Future climate change is predicted to diminish essential natural resource availability in many regions and perhaps globally. The resulting scarcity of water, food and livelihoods could lead to increasingly desperate populations that challenge governments, enhancing the risk of intra- and interstate conflict. Defence establishments and some political scientists view climate change as a potential threat to peace. While the medical literature increasingly recognises climate change as a fundamental health risk, the dimension of climate change-associated conflict has so far received little attention, despite its profound health implications. Many analysts link climate change with a heightened risk of conflict via causal pathways which involve diminishing or changing resource availability. Plausible consequences include: increased frequency of civil conflict in developing countries; terrorism, asymmetric warfare, state failure; and major regional conflicts. The medical understanding of these threats is inadequate, given the scale of health implications. The medical and public health communities have often been reluctant to interpret conflict as a health issue. However, at times, medical workers have proven powerful and effective peace advocates, most notably with regard to nuclear disarmament. The public is more motivated to mitigate climate change when it is framed as a health issue. Improved medical understanding of the association between climate change and conflict could strengthen mitigation efforts and increase cooperation to cope with the climate change that is now inevitable. © The Royal Society of Medicine.

  5. Climate change refugia as a tool for climate adaptation

    Science.gov (United States)

    Climate change refugia, areas relatively buffered from contemporary climate change so as to increase persistence of valued physical, ecological, and cultural resources, are considered as potential adaptation options in the face of anthropogenic climate change. In a collaboration ...

  6. Climate Change and Collective Violence.

    Science.gov (United States)

    Levy, Barry S; Sidel, Victor W; Patz, Jonathan A

    2017-03-20

    Climate change is causing increases in temperature, changes in precipitation and extreme weather events, sea-level rise, and other environmental impacts. It is also causing or contributing to heat-related disorders, respiratory and allergic disorders, infectious diseases, malnutrition due to food insecurity, and mental health disorders. In addition, increasing evidence indicates that climate change is causally associated with collective violence, generally in combination with other causal factors. Increased temperatures and extremes of precipitation with their associated consequences, including resultant scarcity of cropland and other key environmental resources, are major pathways by which climate change leads to collective violence. Public health professionals can help prevent collective violence due to climate change (a) by supporting mitigation measures to reduce greenhouse gas emissions, (b) by promoting adaptation measures to address the consequences of climate change and to improve community resilience, and

  7. Scaling Climate Change Communication for Behavior Change

    Science.gov (United States)

    Rodriguez, V. C.; Lappé, M.; Flora, J. A.; Ardoin, N. M.; Robinson, T. N.

    2014-12-01

    Ultimately, effective climate change communication results in a change in behavior, whether the change is individual, household or collective actions within communities. We describe two efforts to promote climate-friendly behavior via climate communication and behavior change theory. Importantly these efforts are designed to scale climate communication principles focused on behavior change rather than soley emphasizing climate knowledge or attitudes. Both cases are embedded in rigorous evaluations (randomized controlled trial and quasi-experimental) of primary and secondary outcomes as well as supplementary analyses that have implications for program refinement and program scaling. In the first case, the Girl Scouts "Girls Learning Environment and Energy" (GLEE) trial is scaling the program via a Massive Open Online Course (MOOC) for Troop Leaders to teach the effective home electricity and food and transportation energy reduction programs. The second case, the Alliance for Climate Education (ACE) Assembly Program, is advancing the already-scaled assembly program by using communication principles to further engage youth and their families and communities (school and local communities) in individual and collective actions. Scaling of each program uses online learning platforms, social media and "behavior practice" videos, mastery practice exercises, virtual feedback and virtual social engagement to advance climate-friendly behavior change. All of these communication practices aim to simulate and advance in-person train-the-trainers technologies.As part of this presentation we outline scaling principles derived from these two climate change communication and behavior change programs.

  8. Climate variability and change

    CERN Document Server

    Grassl, H

    1998-01-01

    Many factors influence climate. The present knowledge concerning the climate relevance of earth orbital parameters, solar luminosity, volcanoes, internal interactions, and human activities will be reported as well as the vulnerability of emission scenarios for given stabilization goals for greenhouse gas concentrations and the main points of the Kyoto Protocol

  9. Ground water and climate change

    Science.gov (United States)

    Taylor, Richard G.; Scanlon, Bridget; Döll, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F.P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2012-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  10. Ground water and climate change

    Science.gov (United States)

    Taylor, Richard G.; Scanlon, Bridget; Döll, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F. P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2013-04-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  11. Ground Water and Climate Change

    Science.gov (United States)

    Taylor, Richard G.; Scanlon, Bridget; Doell, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F. P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J. -F; Holman, Ian; Treidel, Holger

    2013-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  12. Climate change, responsibility, and justice.

    Science.gov (United States)

    Jamieson, Dale

    2010-09-01

    In this paper I make the following claims. In order to see anthropogenic climate change as clearly involving moral wrongs and global injustices, we will have to revise some central concepts in these domains. Moreover, climate change threatens another value ("respect for nature") that cannot easily be taken up by concerns of global justice or moral responsibility.

  13. Ground water and climate change

    NARCIS (Netherlands)

    Taylor, R.G.; Scanlon, B.; Döll, P.; Rodell, M.; Beek, R. van; Wada, Y.; Longuevergne, L.; Leblanc, M.; Famiglietti, J.S.; Edmunds, M.; Konikow, L.; Green, T.R.; Chen, J.; Taniguchi, M.; Bierkens, M.F.P.; MacDonald, A.; Fan, Y.; Maxwell, R.M.; Yechieli, Y.; Gurdak, J.J.; Allen, D.M.; Shamsudduha, M.; Hiscock, K.; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2012-01-01

    As the world’s largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate chang

  14. Climate change challenges for SEA

    DEFF Research Database (Denmark)

    Larsen, Sanne Vammen

    This paper takes a theoretical perspective on the challenges that climate changes pose for SEA. The theoretical framework used is the sociologist Ulrich Beck’s theory of risk society and the aspects that characterise this society. Climate change is viewed as a risk, and the theory is used to derive...

  15. Generating Arguments about Climate Change

    Science.gov (United States)

    Golden, Barry; Grooms, Jonathon; Sampson, Victor; Oliveri, Robin

    2012-01-01

    This unit is a different and fun way to engage students with an extremely important topic, climate change, which cuts across scientific and nonscientific disciplines. While climate change itself may not be listed in the curriculum of every science class, the authors contend that such a unit is appropriate for virtually any science curriculum.…

  16. Dune erosion under climate change

    NARCIS (Netherlands)

    de Winter, R.C.|info:eu-repo/dai/nl/341476935

    2014-01-01

    This PhD-thesis investigated the effect of future climate change on dune erosion in the Netherlands. At present, dune erosion occurs under a combination of large storm surge and high waves, which are both generated by a storm event. Therefore to investigate the affect of future climate change on dun

  17. Dune erosion under climate change

    NARCIS (Netherlands)

    de Winter, R.C.

    2014-01-01

    This PhD-thesis investigated the effect of future climate change on dune erosion in the Netherlands. At present, dune erosion occurs under a combination of large storm surge and high waves, which are both generated by a storm event. Therefore to investigate the affect of future climate change on dun

  18. Teaching about Global Climate Change

    Science.gov (United States)

    Heffron, Susan Gallagher; Valmond, Kharra

    2011-01-01

    Students are exposed to many different media reports about global climate change. Movies such as "The Day After Tomorrow" and "Ice Age" are examples of instances when movie producers have sought to capture the attention of audiences by augmenting the challenges that climate change poses. Students may receive information from a wide range of media…

  19. Sewer Systems and Climate Change

    NARCIS (Netherlands)

    Brandsma, T.

    1993-01-01

    In this article the impact of climate change on the overflows of sewer systems is assessed. The emphasis is on the overflows of combined sewer systems. The purpose is twofold: first, to obtain a first-order estimate of the impact of climate change on overflows of sewer systems; and second, to obtain

  20. Teaching about Global Climate Change

    Science.gov (United States)

    Heffron, Susan Gallagher; Valmond, Kharra

    2011-01-01

    Students are exposed to many different media reports about global climate change. Movies such as "The Day After Tomorrow" and "Ice Age" are examples of instances when movie producers have sought to capture the attention of audiences by augmenting the challenges that climate change poses. Students may receive information from a wide range of media…

  1. Climate change challenges for SEA

    DEFF Research Database (Denmark)

    Larsen, Sanne Vammen

    This paper takes a theoretical perspective on the challenges that climate changes pose for SEA. The theoretical framework used is the sociologist Ulrich Beck’s theory of risk society and the aspects that characterise this society. Climate change is viewed as a risk, and the theory is used to derive...

  2. Climate change in the circum-North Atlantic region during the last deglaciation

    Science.gov (United States)

    Overpeck, Jonathan T.; Peterson, Larry C.; Kipp, Nilva; Imbrie, John; Rind, David

    1989-01-01

    A survey of new and published palaeoclimate data indicates that both the high- and low-latitude North Atlantic regions were characterized by at least three synchronous periods of abrupt climate change during the last glacial-to-interglacial transition. Climate model results suggest that changes in the melting history of the Laurentide Ice Sheet may explain much of this nonlinear response of the climate system to astronomical (Milankovitch) forcing.

  3. Malaria ecology and climate change

    Science.gov (United States)

    McCord, G. C.

    2016-05-01

    Understanding the costs that climate change will exact on society is crucial to devising an appropriate policy response. One of the channels through while climate change will affect human society is through vector-borne diseases whose epidemiology is conditioned by ambient ecology. This paper introduces the literature on malaria, its cost on society, and the consequences of climate change to the physics community in hopes of inspiring synergistic research in the area of climate change and health. It then demonstrates the use of one ecological indicator of malaria suitability to provide an order-of-magnitude assessment of how climate change might affect the malaria burden. The average of Global Circulation Model end-of-century predictions implies a 47% average increase in the basic reproduction number of the disease in today's malarious areas, significantly complicating malaria elimination efforts.

  4. Climate change experiments in Hamburg

    Energy Technology Data Exchange (ETDEWEB)

    Gubasch, U. [DKRZ, Hamburg (Germany)

    1995-12-31

    Nowadays the anthropogenic climate change is been simulated world wide with a fair number of coupled ocean atmosphere general circulation models (IPCC, 1995). Typical model problems do not only blur the estimates of the anthropogenic climate change, but they also cause errors in the estimates of the natural variability. An accurate representation of the natural variability of the climate system is, however, essential for the detection of the anthropogenic climate change. All model simulations world wide show, even though they differ considerably in their technical details and the experimental setup and the forcing data, similar amplitudes and pattern of the predicted climate change. In the model world it is already at the beginning of the next century possible to detect the anthropogenic climate change in the global mean. If the model results are applied in a `fingerprint analysis`, then it is possible to prove that the climate change during the last 30 years is with a significance of 95 % larger than any other climate change during the last 100 years. The experiments performed in Hamburg show that the experimental conditions are of great importance for the estimate of the future climate. The usual starting point of most of the simulations with present day conditions (1980-1990) is too late, because then a considerable part of the warming since the beginning of the industrialization (ca. 1750) has been neglected. Furthermore it has only recently become clear that the sulphat-aerosols play an important role in the present day climate and in the future climate. The effect of the sulphat aerosols has first been simulated in a number of equilibrium simulations with mixed layer models, but nowadays with globally coupled ocean-atmosphere circulation models

  5. Abrupt physical and chemical changes during 1992-1999, Anderson Springs, SE Geyser Geothermal Field, California

    Science.gov (United States)

    Janik, Cathy J.; Goff, Fraser; Walter, Stephen R.; Sorey, Michael L.; Counce, Dale; Colvard, Elizabeth M.

    2000-01-01

    of steam discharges from the Southeast Geysers. The hot spring waters are low in ions of Cl, B, and Li, but relatively high in HCO3, SO4 and NH4. The stable-isotope compositions (deuterium and oxygen-18) of these waters plot near the global meteoric water line. Geochemical data through time reveal apparent maxima in the concentrations of SO4, Fe, and Mn in 1991 to 1992, before the cluster became hotter. The black-to-gray deposits from the new spring cluster are rich in pyrite and contain anomalous metals. About one-half mile to the east of the hot springs, mineralized water discharges intermittently from an old adit of the Schwartz (Anderson) mine, and enters a tributary of Anderson Creek. This drainage increased substantially in July 1998, and a slurry of mine water and precipitates were transported down the tributary and into Anderson Creek. In December 1998, the adit water was 22°C, and had a chemical composition that was similar to spring waters that once discharged in the ravines surrounding the old Anderson Springs resort. The cause for the abrupt changes that have occurred in thermal features at Anderson Springs is still not resolved. One possibility is that these changes are a response to withdrawal of steam from The Geysers geothermal field over more than 20 years of production. Pressure declines in the geothermal reservoir may have caused a "drying out" of the overlying condensation zone. Induced boiling in this zone and upflow of deep steam to shallower depths would cause heating and vaporization of shallow ground waters. In addition, earthquakes occurring in the vicinity of Anderson Springs have increased significantly after nearby geothermal power plants began operation. These earthquakes may have enhanced surface discharge of thermal fluids along fractures and faults.

  6. Abrupt climate change and high to low latitude teleconnections as simulated in climate models

    DEFF Research Database (Denmark)

    Cvijanovic, Ivana

    High to low latitude atmospheric teleconnections have been a topic of increasing scientific interest since it was shown that high latitude extratropical forcing can induce tropical precipitation shifts through atmosphere-surface ocean interactions. In this thesis, several aspects of high to low l...

  7. Abrupt Climate Change and Origin of Chinese Agriculture from the End of Late Pleistocene to Early Holocene%晚更新世末期-全新世早期的气候突变和中国农业的起源

    Institute of Scientific and Technical Information of China (English)

    侯光良; 肖景义

    2011-01-01

    农业起源和气候变化关系的研究,对于目前人类社会对全球变暖的响应与适应有一定借鉴意义.农业起源需具备一定环境和人口压力、适合的地形、适宜野生稻和黍(粟)生长的气候环境、有从事高级采集一农业活动的文化背景等条件.根据环境演变和考古资料,晚更新世末期一全新世早期,中国经历了一系列气候变化事件.气候变化刺激了农业的形成与发展,新仙女木时期巨大的环境一人口压力促进了农业的产生;8.2 ka BP气候干冷事件推动了农业的扩张.根据农业起源时期的地理环境和典型遗址分布,结合农业起源需具备的条件,综合分析发现:太行山南麓、汾渭谷地一带应该是北方黍(粟)作农业起源地,长江中下游平原一南岭北麓过渡地带应该是南方稻作起源地.%The research on the relationship between Chinese agricultural origin and climate change can be actively used as a significant reference for present human beings' response and adaptation to global warming. Conditions required for the origin of agriculture are: certain environmental premises, population pressure, appropriate landform, suitable climatic conditions for wild rice and millet, cultural background and inheritance of advanced harvesting and agricultural activities. According to the data of the environmental changes and those of archaeology, it can be known that during the period from the end of late Pleistocene to early Holocene China experienced a series of events of climate change. The climate change stimulated the formation and development of agriculture; the tremendous pressure of environment and population during the YD period brought about the existence of agriculture and the event of dramatically cold-dry variation 8.2 kaBP provoked the expansion of agriculture, turning it into the leading industry. Comprehensively analyzing the climate, vegetation, landforms and other natural factors during the

  8. ABRUPT CHANGES OF THE WESTERN PACIFIC SUBTROPICAL HIGH AND ITS INTERANNUAL VARIATION DURING LATE SPRING AND EARLY SUMMER

    Institute of Scientific and Technical Information of China (English)

    舒廷飞; 罗会邦

    2003-01-01

    The 500-hPa geopotential height data used in this paper are from NCEP/NCAR data set for the period from 1979 to 1996 (from March to July). Using pentad average, we define the intensity, westernmost ridge point and mean latitude ofthe subtropical high ridge. Then the wavelet transform and EOF analysis are performed. It is found that there mainly exist three interseasonal abrupt change processes, which correspond to the onset time of the South China Sea Summer Monsoon (SCSSM), the beginning and the end of the Mei-yu respectively. The interannualvariation of the subtropical high in late spring and early summer presents quasi-4-year and 8-year periods.

  9. No Abrupt Changes in redox conditions associated with the end-Permian marine ecosystem collapse in the east Greenland basin

    DEFF Research Database (Denmark)

    Nielsen, Jesper K.; Shen, Y; Piasecki, Stefan

    2010-01-01

    compositions of pyrites from the East Greenland Basin. The size distributions of framboidal pyrites in sediments from a continuous section across the Permian–Triassic boundary reveal that sulfidic conditions in water columns were established about 0.7 m above the extinction event in the East Greenland Basin...... is not indicative of an abrupt change of redox chemistry in water columns, in contrast to previous claims. The integration of isotope and framboidal pyrite data provides a nearly continuous record of ocean chemistry evolution and new insights into the end-Permian extinction and delayed biotic recovery in the East...

  10. Abrupt Changes at the Permian/Triassic Boundary: Tempo of Events from High-Resolution Cyclostratigraphy

    Science.gov (United States)

    Rampino, M. R.; Prokoph, A.; Adler, A. C.

    2000-01-01

    The Permian/Triassic (P/Tr) boundary (251.4 +/- 3 Myr) is marked by the most severe mass extinction in the geologic record. Recently, precise absolute dating has bracketed the marine extinctions and associated carbon-isotope anomaly within less than 1 Myr. We improve this resolution through high-resolution stratigraphy across the P/Tr boundary in the 331-m Gartnerkofel-1 core and nearby Reppwand outcrop section (Carnic Alps, Austria) utilizing FFT and wavelet timeseries analyses of cyclic components in down-hole core logs of density and natural gamma-ray intensity, and carbon-isotopic ratios of bulk samples. The wavelet analysis indicates continuity of deposition across the P/Tr boundary interval, and the timeseries analyses show evidence for persistent cycles in the ratio of approximately 40: 10: 4.7: 2.3 meters, correlated with Milankovitch-band orbital cycles of approximately 412: 100: 40: 20 kyr (eccentricity 1 and 2, obliquity, and precession), and giving a consistent average sedimentation rate of approximately 10 cm/1,000 yr. Milankovitch periods in delta C-13 and density in these shallow-water carbonates were most likely the result of climatically induced oscillations of sea level and climate, coupled with changes in ocean circulation and productivity, that affected sedimentation. Fluctuations in gamma radiation reflect varying input of clay minerals and the presence of shaly interbeds. Throughout the P/Tr boundary interval in the core, the 100,000-year eccentricity cycle seems to be dominant. Weaker obliquity and precession cycles are in line with the location of the Austrian section in the latest Permian, close to the Equator in the western bight of the Tethys, where obliquity and precessional effects on seasonal contrast might be subdued. Using the improved resolution provided by cycle analysis in the GK-1 core, we find that the dramatic change in the faunal record that marks the P/Tr boundary takes place over less than 6m, or less than 60,000 years. In

  11. Vegetation zones in changing climate

    Science.gov (United States)

    Belda, Michal; Holtanova, Eva; Halenka, Tomas; Kalvova, Jaroslava

    2017-04-01

    Climate patterns analysis can be performed for individual climate variables separately or the data can be aggregated using e.g. some kind of climate classification. These classifications usually correspond to vegetation distribution in the sense that each climate type is dominated by one vegetation zone or eco-region. Thus, the Köppen-Trewartha classification provides integrated assessment of temperature and precipitation together with their annual cycle as well. This way climate classifications also can be used as a convenient tool for the assessment and validation of climate models and for the analysis of simulated future climate changes. The Köppen-Trewartha classification is applied on full CMIP5 family of more than 40 GCM simulations and CRU dataset for comparison. This evaluation provides insight on the GCM performance and errors for simulations of the 20th century climate. Common regions are identified, such as Australia or Amazonia, where many state-of-the-art models perform inadequately. Moreover, the analysis of the CMIP5 ensemble for future under RCP 4.5 and RCP 8.5 is performed to assess the climate change for future. There are significant changes for some types in most models e.g. increase of savanna and decrease of tundra for the future climate. For some types significant shifts in latitude can be seen when studying their geographical location in selected continental areas, e.g. toward higher latitudes for boreal climate. Quite significant uncertainty can be seen for some types. For Europe, EuroCORDEX results for both 0.11 and 0.44 degree resolution are validated using Köppen-Trewartha types in comparison to E-OBS based classification. ERA-Interim driven simulations are compared to both present conditions of CMIP5 models as well as their downscaling by EuroCORDEX RCMs. Finally, the climate change signal assessment is provided using the individual climate types. In addition to the changes assessed similarly as for GCMs analysis in terms of the area

  12. Climatic change; Le Changement climatique

    Energy Technology Data Exchange (ETDEWEB)

    Perthuis, Ch. de [Universite de Paris-Dauphine, 75 - Paris (France); Caisse des depots, Mission climat, 75 - Paris (France); Delbosc, A. [Caisse des depots, Mission climat, 75 - Paris (France)

    2009-07-01

    Received ideas about climatic change are a mixture of right and wrong information. The authors use these ideas as starting points to shade light on what we really know and what we believe to know. The book is divided in three main chapters: should we act in front of climatic change? How can we efficiently act? How can we equitably act? For each chapter a series of received ideas is analyzed in order to find those which can usefully contribute to mitigate the environmental, economical and social impacts of climatic change. (J.S.)

  13. Risk communication on climate change

    Energy Technology Data Exchange (ETDEWEB)

    Wardekker, J.A.

    2004-10-01

    For the title study use has been made of available scientific literature, results of new surveys and interviews. In the first part of the study attention is paid to the exchange of information between parties involved in climate change and differences in supply and demand of information. In the second part citizens' views on climate change, problems with communication on climate change, and the resulting consequences and options for communication are dealt with. In this second part also barriers to action that are related or influenced by communication are taken into consideration.

  14. Inhalation anaesthetics and climate change

    DEFF Research Database (Denmark)

    Andersen, Mads Peter Sulbæk; Sander, S P; Nielsen, O J

    2010-01-01

    Although the increasing abundance of CO(2) in our atmosphere is the main driver of the observed climate change, it is the cumulative effect of all forcing agents that dictate the direction and magnitude of the change, and many smaller contributors are also at play. Isoflurane, desflurane......, and sevoflurane are widely used inhalation anaesthetics. Emissions of these compounds contribute to radiative forcing of climate change. To quantitatively assess the impact of the anaesthetics on the forcing of climate, detailed information on their properties of heat (infrared, IR) absorption and atmospheric...

  15. 美国西部近8000年来树木年轮重建降雨量序列中的气候突变%Abrupt changes in an 8000-year precipitation reconstruction for Nevada, the Western USA

    Institute of Scientific and Technical Information of China (English)

    谷湘潜; 江剑民; Franklin Schwing

    2005-01-01

    A scanning t-test algorithm for detecting multiple time-scale abrupt changes in the level of a time-series was used to analyze an 8000 year time series of annual precipitation which was reconstructed from tree rings for the Nevada Climate Division 3 in the western USA. The tree ring samples were gathered from eight states in the southwestern USA. Twenty-two change-points were identified by the algorithm and these were used to partition the tree-ring series into twenty-three relatively Wet/Normal/Dry episodes. These twenty-three episodes were collaborated by a coherency analysis of abrupt changes between the precipitation reconstruction series and the TIC/δ18O records from cored sediments of Pyramid Lake in Nevada, and by comparison with published results from related studies. These episodes were also compared with studies of the global climate change and with records of climate change in China during the same periods. The results suggest that the precipitation reconstruction series is quite valuable for climate-change research on multi-centurial time-scales in the western USA, and that the scanning t-test and coherency detection algorithms may have a wide use for detecting multiple time-scale abrupt changes in a long time series.As the TIC and δ18O record series are high resolution with unequal sampling intervals ranging between 3 and 14 years, a new algorithm was developed to deal with the unequal time intervals in the series.

  16. Ground water and climate change

    NARCIS (Netherlands)

    Taylor, R.G.; Scanlon, B.; Döll, P.; Rodell, M.; Beek, R. van; Wada, Y.; Longuevergne, L.; Leblanc, M.; Famiglietti, J.S.; Edmunds, M.; Konikow, L.; Green, T.R.; Chen, J.; Taniguchi, M.; Bierkens, M.F.P.; MacDonald, A.; Fan, Y.; Maxwell, R.M.; Yechieli, Y.; Gurdak, J.J.; Allen, D.M.; Shamsudduha, M.; Hiscock, K.; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2012-01-01

    As the world’s largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate

  17. Is climate change human induced?

    African Journals Online (AJOL)

    user

    reports follow exhaustive review process, and are widely accepted. In 2007, IPCC's 4th assessment report- 'Climate Change 2007 – Impacts, Adaptation and Vulnerability' came into ... is disturbing regional eco-balance, but increasing vehicular pollution in climate- ... subcontinent by sheltering it from the cold air mass of.

  18. Deliberating Climate Change

    DEFF Research Database (Denmark)

    Agger, Annika; Jelsøe, Erling; Jæger, Birgit

    to include the voice of the citizens into complex scientific and technological issues. The purpose of WWV was to pass on the opinions of ordinary citizens to political decision-makers at The United Nations Climate Summit, COP15, in Copenhagen in December 2009. The authors made a study of the Danish WWV event...

  19. Coping with climate change

    DEFF Research Database (Denmark)

    Zheng, Yuan; Byg, Anja

    2014-01-01

    found across villages regarding the degree of perceived sensitivity and responses despite similar exposure to climate extremes. These differences are partly related to the nature of events and varied socio-economic characteristics of households, which influence their vulnerability and ability to cope...

  20. Deliberating Climate Change

    DEFF Research Database (Denmark)

    Agger, Annika; Jelsøe, Erling; Jæger, Birgit

    to include the voice of the citizens into complex scientific and technological issues. The purpose of WWV was to pass on the opinions of ordinary citizens to political decision-makers at The United Nations Climate Summit, COP15, in Copenhagen in December 2009. The authors made a study of the Danish WWV event...

  1. Eliciting information from experts on the likelihood of rapid climate change.

    Science.gov (United States)

    Arnell, Nigel W; Tompkins, Emma L; Adger, W Neil

    2005-12-01

    The threat of so-called rapid or abrupt climate change has generated considerable public interest because of its potentially significant impacts. The collapse of the North Atlantic Thermohaline Circulation or the West Antarctic Ice Sheet, for example, would have potentially catastrophic effects on temperatures and sea level, respectively. But how likely are such extreme climatic changes? Is it possible actually to estimate likelihoods? This article reviews the societal demand for the likelihoods of rapid or abrupt climate change, and different methods for estimating likelihoods: past experience, model simulation, or through the elicitation of expert judgments. The article describes a survey to estimate the likelihoods of two characterizations of rapid climate change, and explores the issues associated with such surveys and the value of information produced. The surveys were based on key scientists chosen for their expertise in the climate science of abrupt climate change. Most survey respondents ascribed low likelihoods to rapid climate change, due either to the collapse of the Thermohaline Circulation or increased positive feedbacks. In each case one assessment was an order of magnitude higher than the others. We explore a high rate of refusal to participate in this expert survey: many scientists prefer to rely on output from future climate model simulations.

  2. Changing heathlands in a changing climate

    DEFF Research Database (Denmark)

    Ransijn, Johannes

    ) a study on the effects of elevated atmospheric CO2-concentration, warming and drought on the photosynthetic capacity and phenology of C. vulgaris and D. flexuosa in an outdoor climate change experiment on a grassy heathland in Denmark; 4) a study on climate change impacts on the competitive interactions...... and flexibly reduces its green biomass under drought conditions. C. vulgaris is less flexible and hardly adjusts photosynthetic capacity or green biomass to drought or warming. Despite these differential responses, competitive interactions were robust. C. vulgaris, in the building phase, outcompetes D...... plant communities. Many heathlands have shifted from dwarf shrub dominance to grass dominance and climatic change might affect the competitive balance between dwarf shrubs and grasses. We looked at heathland vegetation dynamics and heathland plant responses to climatic change at different spatial...

  3. Integrated climate change risk assessment:

    DEFF Research Database (Denmark)

    Kaspersen, Per Skougaard; Halsnæs, Kirsten

    2017-01-01

    Risk assessments of flooding in urban areas during extreme precipitation for use in, for example, decision-making regarding climate adaptation, are surrounded by great uncertainties stemming from climate model projections, methods of downscaling and the assumptions of socioeconomic impact models....... enables the relative importance of the different factors (i.e. degree of climate change, assets value, discount rate etc.) to be determined, thus influencing the overall output of the assessment.......Risk assessments of flooding in urban areas during extreme precipitation for use in, for example, decision-making regarding climate adaptation, are surrounded by great uncertainties stemming from climate model projections, methods of downscaling and the assumptions of socioeconomic impact models...... to address the complex linkages between the different kinds of data required in assessing climate adaptation. It emphasizes that the availability of spatially explicit data can reduce the overall uncertainty of the risk assessment and assist in identifying key vulnerable assets. The usefulness...

  4. Climate change; Le changement climatique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Based on contributions on 120 French and foreign scientists representing different disciplines (mathematics, physics, mechanics, chemistry, biology, medicine, and so on), this report proposes an overview of the scientific knowledge and debate about climate change. It discusses the various indicators of climate evolution (temperatures, ice surfaces, sea level, biological indicators) and the various factors which may contribute to climate evolution (greenhouse gases, solar radiation). It also comments climate evolutions in the past as they can be investigated through some geological, thermal or geochemical indicators. Then, the authors describe and discuss the various climate mechanisms: solar activity, oceans, ice caps, greenhouse gases. In a third part, the authors discuss the different types of climate models which differ by the way they describe processes, and the current validation process for these models

  5. Can Climate Change Negotiations Succeed?

    Directory of Open Access Journals (Sweden)

    Jon Hovi

    2013-09-01

    Full Text Available More than two decades of climate change negotiations have produced a series of global climate agreements, such as the Kyoto Protocol and the Copenhagen Accords, but have nevertheless made very limited progress in curbing global emissions of greenhouse gases. This paper considers whether negotiations can succeed in reaching an agreement that effectively addresses the climate change problem. To be effective, a climate agreement must cause substantial emissions reductions either directly (in the agreement's own lifetime or indirectly (by paving the way for a future agreement that causes substantial emissions reductions directly. To reduce global emissions substantially, an agreement must satisfy three conditions. Firstly, participation must be both comprehensive and stable. Secondly, participating countries must accept deep commitments. Finally, the agreement must obtain high compliance rates. We argue that three types of enforcement will be crucial to fulfilling these three conditions: (1 incentives for countries to ratify with deep commitments, (2 incentives for countries that have ratified with deep commitments to abstain from withdrawal, and (3 incentives for countries having ratified with deep commitments to comply with them. Based on assessing the constraints that characterize the climate change negotiations, we contend that adopting such three-fold potent enforcement will likely be politically infeasible, not only within the United Nations Framework Convention on Climate Change, but also in the framework of a more gradual approach. Therefore, one should not expect climate change negotiations to succeed in producing an effective future agreement—either directly or indirectly.

  6. Can Climate Change Negotiations Succeed?

    Directory of Open Access Journals (Sweden)

    Jon Hovi

    2013-09-01

    Full Text Available More than two decades of climate change negotiations have produced a series of global climate agreements, such as the Kyoto Protocol and the Copenhagen Accords, but have nevertheless made very limited progress in curbing global emissions of greenhouse gases. This paper considers whether negotiations can succeed in reaching an agreement that effectively addresses the climate change problem. To be effective, a climate agreement must cause substantial emissions reductions either directly (in the agreement's own lifetime or indirectly (by paving the way for a future agreement that causes substantial emissions reductions directly. To reduce global emissions substantially, an agreement must satisfy three conditions. Firstly, participation must be both comprehensive and stable. Secondly, participating countries must accept deep commitments. Finally, the agreement must obtain high compliance rates. We argue that three types of enforcement will be crucial to fulfilling these three conditions: (1 incentives for countries to ratify with deep commitments, (2 incentives for countries that have ratified with deep commitments to abstain from withdrawal, and (3 incentives for countries having ratified with deep commitments to comply with them. Based on assessing the constraints that characterize the climate change negotiations, we contend that adopting such three-fold potent enforcement will likely be politically infeasible, not only within the United Nations Framework Convention on Climate Change, but also in the framework of a more gradual approach. Therefore, one should not expect climate change negotiations to succeed in producing an effective future agreement—either directly or indirectly.

  7. Climate Change Science Program Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Climate Change Science Program (CCSP) Collection consists of publications and other resources produced between 2007 and 2009 by the CCSP with the intention of...

  8. Cities lead on climate change

    Science.gov (United States)

    Pancost, Richard D.

    2016-04-01

    The need to mitigate climate change opens up a key role for cities. Bristol's year as a Green Capital led to great strides forward, but it also revealed that a creative and determined partnership across cultural divides will be necessary.

  9. Climate Change and Human Health

    Directory of Open Access Journals (Sweden)

    Jan C. Semenza

    2014-07-01

    Full Text Available Climate change impacts on human health span the trajectory of time—past, present, and future. The key finding from the Working Group II, Fifth Assessment Report (AR5 of the Intergovernmental Panel on Climate Change (IPCC states that health impacts due to climate change have already occurred in the past, are currently occurring and will continue to occur, at least for the foreseeable future, even with immediate reductions in greenhouse gas emissions [1]. According to the IPCC, there has been increased heat-related mortality and decreased cold-related mortality in some regions as a result of warming (Box 1. Moreover, local changes in temperature and rainfall have altered the distribution of some water-borne illnesses and disease vectors. Impacts of climate-related extremes include alteration of ecosystems, disruption of food production and water supply, damage to infrastructure and settlements, morbidity and mortality, and consequences for mental health and human well-being [1]. [...

  10. Climate change and water resources

    Energy Technology Data Exchange (ETDEWEB)

    Younos, Tamim [The Cabell Brand Center for Global Poverty and Resource Sustainability Studies, Salem, VA (United States); Grady, Caitlin A. (ed.) [Purdue Univ., West Lafayette, IN (United States). Ecological Sciences and Engineering Program

    2013-07-01

    This volume presents nine chapters prepared by international authors and highlighting various aspects of climate change and water resources. Climate change models and scenarios, particularly those related to precipitation projection, are discussed and uncertainties and data deficiencies that affect the reliability of predictions are identified. The potential impacts of climate change on water resources (including quality) and on crop production are analyzed and adaptation strategies for crop production are offered. Furthermore, case studies of climate change mitigation strategies, such as the reduction of water use and conservation measures in urban environments, are included. This book will serve as a valuable reference work for researchers and students in water and environmental sciences, as well as for governmental agencies and policy makers.

  11. Making Sense of Climate Change

    DEFF Research Database (Denmark)

    Blichfeldt, Nikolaj Vendelbo

    The thesis is an ethnographic description of a climate change mitigation campaign among retirees in the urban residential community Dongping Lane in central Hangzhou, and an examination of local understandings of connections between everyday life in the community and global climate change......, as a point of departure for an examination of what happens when a requirement to save energy and resources, as a response to global climate change, encounters local ways of knowing the world. Developed through meetings, workshops, competitions and the promotion of exemplary individuals, the campaign...... is conceived as part of wider state-sponsored efforts to foster civilized behavior and a sense of belonging to the residential community among urban citizens in China. The campaigners connect unspectacular everyday consumer practices with climate change and citizenship by showing that among them, making...

  12. Climate change and group dynamics

    NARCIS (Netherlands)

    Postmes, Tom

    2015-01-01

    The characteristics and views of people sceptical about climate change have been analysed extensively. A study now confirms that sceptics in the US have some characteristics of a social movement, but shows that the same group dynamics propel believers

  13. Welfare impacts of climate change

    NARCIS (Netherlands)

    Hof, Andries F.

    2015-01-01

    Climate change can affect well-being in poor economies more than previously shown if its effect on economic growth, and not only on current production, is considered. But this result does not necessarily suggest greater mitigation efforts are required.

  14. Welfare impacts of climate change

    NARCIS (Netherlands)

    Hof, Andries F.

    2015-01-01

    Climate change can affect well-being in poor economies more than previously shown if its effect on economic growth, and not only on current production, is considered. But this result does not necessarily suggest greater mitigation efforts are required.

  15. Climate change and group dynamics

    NARCIS (Netherlands)

    Postmes, Tom

    2015-01-01

    The characteristics and views of people sceptical about climate change have been analysed extensively. A study now confirms that sceptics in the US have some characteristics of a social movement, but shows that the same group dynamics propel believers

  16. Climate change: Unattributed hurricane damage

    Science.gov (United States)

    Hallegatte, Stéphane

    2015-11-01

    In the United States, hurricanes have been causing more and more economic damage. A reanalysis of the disaster database using a statistical method that accounts for improvements in resilience opens the possibility that climate change has played a role.

  17. Responsible Reaction To Climate Change

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    China calls for turning UNFCCC provisions into concrete actions Never before has climate change been as prominent on the public agenda as it is today.Its rele- vance was highlighted once again when more than 10,000 delegates from over 180 countries flocked to Bali early this month to discuss the topic.Environment officials as well as representatives from intergovernmental and nongovernmental organizations gath- ered on the Indonesian island on December 3-14 for the UN Climate Change Conference.

  18. Climate Change and National Security

    Science.gov (United States)

    2013-02-01

    atmosphere, which is causing warming of global temperatures as well as more extreme and less predictable weather patterns. While this issue is debated in...develop unique, policy-relevant solutions to complex global challenges. About the CCAPS Program The Climate Change and African Political Stability...political circles, scientists overwhelmingly agree that human-induced or anthropogenic climate change is real. Given the complexity of the issue, there

  19. Social protection and climate change

    DEFF Research Database (Denmark)

    Johnson, Craig; Bansha Dulal, Hari; Prowse, Martin Philip

    2013-01-01

    This article lays the foundation for this special issue on social protection and climate change, introducing and evaluating the ways in which the individual articles contribute to our understanding of the subject.......This article lays the foundation for this special issue on social protection and climate change, introducing and evaluating the ways in which the individual articles contribute to our understanding of the subject....

  20. Abrupt fire regime change may cause landscape-wide loss of mature obligate seeder forests.

    Science.gov (United States)

    Bowman, David M J S; Murphy, Brett P; Neyland, Dominic L J; Williamson, Grant J; Prior, Lynda D

    2014-03-01

    Obligate seeder trees requiring high-severity fires to regenerate may be vulnerable to population collapse if fire frequency increases abruptly. We tested this proposition using a long-lived obligate seeding forest tree, alpine ash (Eucalyptus delegatensis), in the Australian Alps. Since 2002, 85% of the Alps bioregion has been burnt by several very large fires, tracking the regional trend of more frequent extreme fire weather. High-severity fires removed 25% of aboveground tree biomass, and switched fuel arrays from low loads of herbaceous and litter fuels to high loads of flammable shrubs and juvenile trees, priming regenerating stands for subsequent fires. Single high-severity fires caused adult mortality and triggered mass regeneration, but a second fire in quick succession killed 97% of the regenerating alpine ash. Our results indicate that without interventions to reduce fire severity, interactions between flammability of regenerating stands and increased extreme fire weather will eliminate much of the remaining mature alpine ash forest. © 2013 John Wiley & Sons Ltd.

  1. Climate Change Communication Research: Trends and Implications ...

    African Journals Online (AJOL)

    Climate Change Communication Research: Trends and Implications. ... journal articles in the areas communication, climate change and agriculture. ... climate change communication to farmers have been purely elitist and quantitative, which ...

  2. Update on global climate change.

    Science.gov (United States)

    Weber, Carol J

    2010-01-01

    Global climate change brings new challenges to the control of infectious diseases. Since many waterborne and vector-borne pathogens are highly sensitive to temperature and rainfall, health risks resulting from a warming and more variable climate are potentially huge. Global climate change involves the entire world, but the poorest countries will suffer the most. Nations are coming together to address what can be done to reduce greenhouse gas emissions and cope with inevitable temperature increases. A key component of any comprehensive mitigation and adaptation plan is a strong public health infrastructure across the world. Nothing less than global public health security is at stake.

  3. Climate Change in Developing Countries

    Energy Technology Data Exchange (ETDEWEB)

    Van Drunen, M.A.; Lasage, R.; Dorlands, C. (eds.) [Free University, Amsterdam (Netherlands)

    2006-09-15

    This book presents an overview of the studies conducted by the Netherlands Climate Change Studies Assistance programme. The programme was set up in recognition of the need for developing countries, in particular, to face the challenges confronting all countries under the UN Framework Convention on Climate Change. The book presents an overview of the main results in 13 countries: Bolivia, Colombia, Ecuador, Egypt, Ghana, Kazakhstan, Mali, Mongolia, Senegal, Surinam, Vietnam, Yemen and Zimbabwe. It provides a critical evaluation of the methodologies and approaches used, a cross-country synthesis and recommendations for further studies. Subjects dealt with include not only impact studies, but also vulnerability and adaptation, mitigation and climate related policy.

  4. Trends and abrupt changes in 104 years of ice cover and water temperature in a dimictic lake in response to air temperature, wind speed, and water clarity drivers

    Science.gov (United States)

    Magee, Madeline R.; Wu, Chin H.; Robertson, Dale M.; Lathrop, Richard C.; Hamilton, David P.

    2016-05-01

    abrupt changes in air temperature and wind speed. Average summer hypolimnetic temperature and fall turnover date exhibit significant differences between the third period and the first two periods. Changes in ice cover (ice-on and ice-off dates, ice cover duration, and maximum ice thickness) exhibit an abrupt change after 1994, which was related in part to the warm El Niño winter of 1997-1998. Under-ice water temperature, freeze-over water temperature, hypolimnetic temperature, fall turnover date, and stratification duration demonstrate a significant difference in the third period (1994-2014), when air temperature was warmest and wind speeds decreased rather abruptly. The trends in ice cover and water temperature demonstrate responses to both long-term and abrupt changes in meteorological conditions that can be complemented with numerical modeling to better understand how these variables will respond in a future climate.

  5. CLIMATE CHANGES: CAUSES AND IMPACT

    Directory of Open Access Journals (Sweden)

    Camelia Slave

    2013-07-01

    Full Text Available Present brings several environmental problems for people. Many of these are closely related, but by far the most important problem is the climate change. In the course of Earth evolution, climate has changed many times, sometimes dramatically. Warmer eras always replaced and were in turn replaced by glacial ones. However, the climate of the past almost ten thousand years has been very stable. During this period human civilization has also developed. In the past nearly 100 years - since the beginning of industrialization - the global average temperature has increased by approx. 0.6 ° C (after IPCC (Intergovernmental Panel on Climate Change, faster than at any time in the last 1000 years.

  6. Late Quaternary changes in climate

    Energy Technology Data Exchange (ETDEWEB)

    Holmgren, K.; Karlen, W. [Stockholm Univ. (Sweden). Dept. of Physical Geography

    1998-12-01

    This review concerns the Quaternary climate with an emphasis on the last 200 000 years. The present state of art in this field is described and evaluated. The review builds on a thorough examination of classic and recent literature. General as well as detailed patterns in climate are described and the forcing factors and feed-back effects are discussed. Changes in climate occur on all time-scales. During more than 90% of the Quaternary period earth has experienced vast ice sheets, i.e. glaciations have been more normal for the period than the warm interglacial conditions we face today. Major changes in climate, such as the 100 000 years glacial/interglacial cycle, are forced by the Milankovitch three astronomical cycles. Because the cycles have different length climate changes on earth do not follow a simple pattern and it is not possible to find perfect analogues of a certain period in the geological record. Recent discoveries include the observation that major changes in climate seem to occur at the same time on both hemispheres, although the astronomical theory implies a time-lag between latitudes. This probably reflects the influence of feed-back effects within the climate system. Another recent finding of importance is the rapid fluctuations that seem to be a normal process. When earth warmed after the last glaciation temperature jumps of up to 10 deg C occurred within less than a decade and precipitation more than doubled within the same time. The forcing factors behind these rapid fluctuations are not well understood but are believed to be a result of major re-organisations in the oceanic circulation. Realizing that nature, on its own, can cause rapid climate changes of this magnitude put some perspective on the anthropogenic global warming debate, where it is believed that the release of greenhouse gases will result in a global warming of a few C. To understand the forcing behind natural rapid climate changes appears as important as to understand the role

  7. Biodiversity redistribution under climate change

    DEFF Research Database (Denmark)

    Pecl, Gretta T.; Bastos, Miguel; Bell, Johann D.

    2017-01-01

    Distributions of Earth’s species are changing at accelerating rates, increasingly driven by humanmediated climate change. Such changes are already altering the composition of ecological communities, but beyond conservation of natural systems, how and why does this matter? We review evidence...... that climate-driven species redistribution at regional to global scales affects ecosystem functioning, human well-being, and the dynamics of climate change itself. Production of natural resources required for food security, patterns of disease transmission, and processes of carbon sequestration are all altered...... by changes in species distribution. Consideration of these effects of biodiversity redistribution is critical yet lacking in most mitigation and adaptation strategies, including the United Nation’s Sustainable Development Goals....

  8. Ocean Observations of Climate Change

    Science.gov (United States)

    Chambers, Don

    2016-01-01

    The ocean influences climate by storing and transporting large amounts of heat, freshwater, and carbon, and exchanging these properties with the atmosphere. About 93% of the excess heat energy stored by the earth over the last 50 years is found in the ocean. More than three quarters of the total exchange of water between the atmosphere and the earth's surface through evaporation and precipitation takes place over the oceans. The ocean contains 50 times more carbon than the atmosphere and is at present acting to slow the rate of climate change by absorbing one quarter of human emissions of carbon dioxide from fossil fuel burning, cement production, deforestation and other land use change.Here I summarize the observational evidence of change in the ocean, with an emphasis on basin- and global-scale changes relevant to climate. These include: changes in subsurface ocean temperature and heat content, evidence for regional changes in ocean salinity and their link to changes in evaporation and precipitation over the oceans, evidence of variability and change of ocean current patterns relevant to climate, observations of sea level change and predictions over the next century, and biogeochemical changes in the ocean, including ocean acidification.

  9. Climate Change in New England | Energy and Global Climate ...

    Science.gov (United States)

    2017-04-10

    EPA Region 1's Energy and Climate Unit and Oceans and Coastal Unit provide information and technical assistance on climate change impacts and adaptation, resilience and preparedness to climate disruptions

  10. Early Paleozoic ridge subduction in the Chinese Altai: Insight from the abrupt change in zircon Hf isotopic compositions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Zircons were separated from granitoids, gneisses, and sedimentary rocks of the Chinese Altai. Those with igneous characteristics yielded U-Pb ages of 280-2800 Ma, recording a long history of magmatic activity in the region. Zircon Hf isotopic compositions show an abrupt change at ~420 Ma, indicating that prior to that time the magmas came from both ancient and juvenile sources, whereas younger magmas were derived mainly from juvenile material. This may imply that the lithosphere was signifi- cantly modified in composition by a rapid addition of melt from the mantle. We suggest that this dramatic change was due to the onset of ridge subduction, which can account not only for the formation of voluminous granitoids, mafic rocks with complex compositions, and the association of adakite + high-Mg andesite + boninite + Nb-enriched basalt, but also for the coeval high-T, low-P metamorphism.

  11. Early Paleozoic ridge subduction in the Chinese Altai:Insight from the abrupt change in zircon Hf isotopic compositions

    Institute of Scientific and Technical Information of China (English)

    SUN Min; LONG XiaoPing; CAI KeDa; JIANG YingDe; WANG BuYun; YUAN Chao; ZHAO GuoChun; XIAO WenJiao; WU FuYuan

    2009-01-01

    Zircons were separated from granitoids,gneisses,and sedimentary rocks of the Chinese Altai.Those with igneous characteristics yielded U-Pb ages of 280-2800 Ma,recording a long history of magmatic activity in the region.Zircon Hf isotopic compositions show an abrupt change at ~420 Ma,indicating that prior to that time the magmas came from both ancient and juvenile sources,whereas younger magmas were derived mainly from juvenile material.This may imply that the lithosphere was significantly modified in composition by a rapid addition of melt from the mantle.We suggest that this dramatic change was due to the onset of ridge subduction,which can account not only for the formation of voluminous granitoids,mafic rocks with complex compositions,and the association of adakite + high-Mg andesite+boninite + Nb-enriched basalt,but also for the coeval high-T,Iow-P metamorphism.

  12. Climate change and food security.

    Science.gov (United States)

    Gregory, P J; Ingram, J S I; Brklacich, M

    2005-11-29

    Dynamic interactions between and within the biogeophysical and human environments lead to the production, processing, distribution, preparation and consumption of food, resulting in food systems that underpin food security. Food systems encompass food availability (production, distribution and exchange), food access (affordability, allocation and preference) and food utilization (nutritional and societal values and safety), so that food security is, therefore, diminished when food systems are stressed. Such stresses may be induced by a range of factors in addition to climate change and/or other agents of environmental change (e.g. conflict, HIV/AIDS) and may be particularly severe when these factors act in combination. Urbanization and globalization are causing rapid changes to food systems. Climate change may affect food systems in several ways ranging from direct effects on crop production (e.g. changes in rainfall leading to drought or flooding, or warmer or cooler temperatures leading to changes in the length of growing season), to changes in markets, food prices and supply chain infrastructure. The relative importance of climate change for food security differs between regions. For example, in southern Africa, climate is among the most frequently cited drivers of food insecurity because it acts both as an underlying, ongoing issue and as a short-lived shock. The low ability to cope with shocks and to mitigate long-term stresses means that coping strategies that might be available in other regions are unavailable or inappropriate. In other regions, though, such as parts of the Indo-Gangetic Plain of India, other drivers, such as labour issues and the availability and quality of ground water for irrigation, rank higher than the direct effects of climate change as factors influencing food security. Because of the multiple socio-economic and bio-physical factors affecting food systems and hence food security, the capacity to adapt food systems to reduce their

  13. Comment on ``Abrupt environmental change in Canada's northernmost lake inferred from fossil diatom and pigment stratigraphy'' by Dermot Antoniades et al.

    Science.gov (United States)

    Gajewski, K.

    2008-04-01

    Antoniades et al. [2007; hereinafter referred to as A07] present an analysis of a 19-cm lake sediment core from Ward Hunt Island from northern Canada. They conclude that a significant and abrupt change in the aquatic communities occurred in this lake during the past 2 centuries that was unusual with respect to the previous 8ka. In the paper, and especially in quotes to the press (e.g., http://www.cbc.ca; http://www.sciencedaily.com; http://scitizen.com) the authors conclude that their results, along with those from Smol et al. [2005] provide evidence for amplification of climates with latitude due to human caused global warming, an event unique in the past 8 ka. However, there are a number of problems in these data and flaws in the author's interpretations that render their results questionable. Their conclusions do not hold up to scrutiny as they do not concord with other information we have about climate variability in the Arctic. I have four major comments on the data, and several on the interpretation.

  14. Recent Studies on Attributions of Climate Change in China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zongci; DING Yihui; LUO Yong; Wang Shaowu

    2005-01-01

    Attributions of floods/cooler along the Yangtze River Valley and droughts/warmer in North China for the last 25 years have been reviewed in this paper. Both natural climate variability and human activities are considered. Some stronger evidences contributed to the natural climate variability, such as decadal and interdecadal variabilities of East Asian summer monsoon, the periodicities and transitions of rainfall and temperature changes in China, abrupt climate change, NAO, AO, AAO, ENSO, and snow cover. The signals produced by the human activities such as greenhouse gases and "brown clouds" likely play the role for the patterns. But the physical feedbacks and mechanisms still keep ambiguous and vague. More researches should be carried out in future to solve this issue.

  15. Climate change adaptation in Ethiopia

    DEFF Research Database (Denmark)

    Weldegebriel, Zerihun Berhane; Prowse, Martin

    Ethiopia is vulnerable to climate change due to its limited development and dependence on agriculture. Social protection schemes like the Productive Safety Net Programme (PSNP) can play a positive role in promoting livelihoods and enhancing households’ risk management. This article examines......, they suggest the PSNP may not be helping smallholders diversify income sources in a positive manner for climate adaptation. The article concludes by arguing for further investigation of the PSNP’s influence on smallholders’ adaptation strategies....

  16. Climate change adaptation in Ethiopia

    DEFF Research Database (Denmark)

    Weldegebriel, Zerihun Berhane; Prowse, Martin

    Ethiopia is vulnerable to climate change due to its limited development and dependence on agriculture. Social protection schemes like the Productive Safety Net Programme (PSNP) can play a positive role in promoting livelihoods and enhancing households’ risk management. This article examines......, they suggest the PSNP may not be helping smallholders diversify income sources in a positive manner for climate adaptation. The article concludes by arguing for further investigation of the PSNP’s influence on smallholders’ adaptation strategies....

  17. Health Effects of Climate Change

    Science.gov (United States)

    ... resulting health effects. Extreme weather events due to climate change may cause people to experience geographic displacement, damage to their property, loss of loved ones, and chronic stress—all of which can negatively affect ... change may be associated with staple food shortages, malnutrition, ...

  18. Climate Change: Meeting the Challenge

    Science.gov (United States)

    Chance, Paul; Heward, William L.

    2010-01-01

    In "Climate Change: Meeting the Challenge," we conclude the special section by assuming that you have been persuaded by Thompson's paper or other evidence that global warming is real and poses a threat that must be dealt with, and that for now the only way to deal with it is by changing behavior. Then we ask what you, as behavior analysts, can do…

  19. Climate change: Wilderness's greatest challenge

    Science.gov (United States)

    Nathan L. Stephenson; Connie Millar

    2014-01-01

    Anthropogenic climatic change can no longer be considered an abstract possibility. It is here, its effects are already evident, and changes are expected to accelerate in coming decades, profoundly altering wilderness ecosystems. At the most fundamental level, wilderness stewards will increasingly be confronted with a trade-off between untrammeled wilderness character...

  20. Dislocated interests and climate change

    Science.gov (United States)

    Davis, Steven J.; Diffenbaugh, Noah

    2016-06-01

    The predicted effects of climate change on surface temperatures are now emergent and quantifiable. The recent letter by Hansen and Sato (2016 Environ. Res. Lett. 11 034009) adds to a growing number of studies showing that warming over the past four decades has shifted the distribution of temperatures higher almost everywhere, with the largest relative effects on summer temperatures in developing regions such as Africa, South America, southeast Asia, and the Middle East (e.g., Diffenbaugh and Scherer 2011 Clim. Change 107 615-24 Anderson 2011 Clim. Change 108 581; Mahlstein et al 2012 Geophys. Res. Lett. 39 L21711). Hansen and Sato emphasize that although these regions are warming disproportionately, their role in causing climate change—measured by cumulative historical CO2 emissions produced—is small compared to the US and Europe, where the relative change in temperatures has been less. This spatial and temporal mismatch of climate change impacts and the burning of fossil fuels is a critical dislocation of interests that, as the authors note, has ‘substantial implications for global energy and climate policies.’ Here, we place Hansen and Sato’s ‘national responsibilities’ into a broader conceptual framework of problematically dislocated interests, and briefly discuss the related challenges for global climate mitigation efforts.

  1. Three eras of climate change

    Energy Technology Data Exchange (ETDEWEB)

    Huq, Saleemul; Toulmin, Camilla

    2006-10-15

    Climate change as a global challenge has evolved through a series of stages in the last few decades. We are now on the brink of a new era which will see the terms of the debate shift once again. The different eras are characterised by the scientific evidence, public perceptions, responses and engagement of different groups to address the problem. In the first era, from the late 1980s to 2000, climate change was seen as an “environmental” problem to do with prevention of future impacts on the planet's climate systems over the next fifty to hundred years, through reductions in emissions of greenhouse gases, known as “mitigation”. The second era can be said to have started around the turn of the millennium, with the recognition that there will be some unavoidable impacts from climate change in the near term (over the next decade or two). These impacts must be coped with through “adaptation”, as well as mitigation, to prevent much more severe and possibly catastrophic impacts in the longer term. It has become clear that many of the impacts of climate change in the near term are likely to fall on the poorest countries and communities. The third era, which we are just about to enter, will see the issue change from tackling an environmental or development problem to a question of “global justice”. It will engage with a much wider array of citizens from around the world than previous eras.

  2. Climate Change and Fish Availability

    Science.gov (United States)

    Teng, Paul P. S.; Lassa, Jonatan; Caballero-Anthony, Mely

    Human consumption of fish has been trending upwards in the past decades and this is projected to continue. The main sources of fish are from wild fisheries (marine and freshwater) and aquaculture. Climate change is anticipated to affect the availability of fish through its effect on these two sources as well as on supply chain processes such as storage, transport, processing and retail. Climate change is known to result in warmer and more acid oceans. Ocean acidification due to higher CO2 concentration levels at sea modifies the distribution of phytoplankton and zooplankton to affect wild, capture fisheries. Higher temperature causes warm-water coral reefs to respond with species replacement and bleaching, leading to coral cover loss and habitat loss. Global changes in climatic systems may also cause fish invasion, extinction and turnover. While this may be catastrophic for small scale fish farming in poor tropical communities, there are also potential effects on animal protein supply shifts at local and global scales with food security consequences. This paper discusses the potential impacts of climate change on fisheries and aquaculture in the Asian Pacific region, with special emphasis on Southeast Asia. The key question to be addressed is “What are the impacts of global climate change on global fish harvests and what does it mean to the availability of fish?”

  3. Western water and climate change.

    Science.gov (United States)

    Dettinger, Michael; Udall, Bradley; Georgakakos, Aris

    2015-12-01

    The western United States is a region long defined by water challenges. Climate change adds to those historical challenges, but does not, for the most part, introduce entirely new challenges; rather climate change is likely to stress water supplies and resources already in many cases stretched to, or beyond, natural limits. Projections are for continued and, likely, increased warming trends across the region, with a near certainty of continuing changes in seasonality of snowmelt and streamflows, and a strong potential for attendant increases in evaporative demands. Projections of future precipitation are less conclusive, although likely the northern-most West will see precipitation increases while the southernmost West sees declines. However, most of the region lies in a broad area where some climate models project precipitation increases while others project declines, so that only increases in precipitation uncertainties can be projected with any confidence. Changes in annual and seasonal hydrographs are likely to challenge water managers, users, and attempts to protect or restore environmental flows, even where annual volumes change little. Other impacts from climate change (e.g., floods and water-quality changes) are poorly understood and will likely be location dependent. In this context, four iconic river basins offer glimpses into specific challenges that climate change may bring to the West. The Colorado River is a system in which overuse and growing demands are projected to be even more challenging than climate-change-induced flow reductions. The Rio Grande offers the best example of how climate-change-induced flow declines might sink a major system into permanent drought. The Klamath is currently projected to face the more benign precipitation future, but fisheries and irrigation management may face dire straits due to warming air temperatures, rising irrigation demands, and warming waters in a basin already hobbled by tensions between endangered fisheries

  4. Climate engineering research : A precautionary response to climate change?

    NARCIS (Netherlands)

    Reynolds, J.L.; Fleurke, F.M.

    2013-01-01

    In the face of dire forecasts for anthropogenic climate change, climate engineering is increasingly discussed as a possible additional set of responses to reduce climate change’s threat. These proposals have been controversial, in part because they – like climate change itself – pose uncertain risks

  5. Climate engineering research : A precautionary response to climate change?

    NARCIS (Netherlands)

    Reynolds, J.L.; Fleurke, F.M.

    2013-01-01

    In the face of dire forecasts for anthropogenic climate change, climate engineering is increasingly discussed as a possible additional set of responses to reduce climate change’s threat. These proposals have been controversial, in part because they – like climate change itself – pose uncertain risks

  6. Rapid climate change did not cause population collapse at the end of the European Bronze Age.

    Science.gov (United States)

    Armit, Ian; Swindles, Graeme T; Becker, Katharina; Plunkett, Gill; Blaauw, Maarten

    2014-12-02

    The impact of rapid climate change on contemporary human populations is of global concern. To contextualize our understanding of human responses to rapid climate change it is necessary to examine the archeological record during past climate transitions. One episode of abrupt climate change has been correlated with societal collapse at the end of the northwestern European Bronze Age. We apply new methods to interrogate archeological and paleoclimate data for this transition in Ireland at a higher level of precision than has previously been possible. We analyze archeological (14)C dates to demonstrate dramatic population collapse and present high-precision proxy climate data, analyzed through Bayesian methods, to provide evidence for a rapid climatic transition at ca. 750 calibrated years B.C. Our results demonstrate that this climatic downturn did not initiate population collapse and highlight the nondeterministic nature of human responses to past climate change.

  7. Double Exposure: Photographing Climate Change

    Science.gov (United States)

    Arnold, D. P.; Wake, C. P.; Romanow, G. B.

    2008-12-01

    Double Exposure, Photographing Climate Change, is a fine-art photography exhibition that examines climate change through the prism of melting glaciers. The photographs are twinned shots of glaciers, taken in the mid-20th century by world-renowned photographer Brad Washburn, and in the past two years by Boston journalist/photographer David Arnold. Arnold flew in Washburn's aerial "footprints", replicating stunning black and white photographs, and documenting one irreversible aspect of climate change. Double Exposure is art with a purpose. It is designed to educate, alarm and inspire its audiences. Its power lies in its beauty and the shocking changes it has captured through a camera lens. The interpretive text, guided by numerous experts in the fields of glaciology, global warming and geology, helps convey the message that climate change has already forced permanent changes on the face of our planet. The traveling exhibit premiered at Boston's Museum of Science in April and is now criss-crossing the nation. The exhibit covers changes in the 15 glaciers that have been photographed as well as related information about global warming's effect on the planet today.

  8. Western water and climate change

    Science.gov (United States)

    Dettinger, Michael; Udall, Bradley; Georgakakos, Aris P.

    2015-01-01

    The western United States is a region long defined by water challenges. Climate change adds to those historical challenges, but does not, for the most part, introduce entirely new challenges; rather climate change is likely to stress water supplies and resources already in many cases stretched to, or beyond, natural limits. Projections are for continued and, likely, increased warming trends across the region, with a near certainty of continuing changes in seasonality of snowmelt and streamflows, and a strong potential for attendant increases in evaporative demands. Projections of future precipitation are less conclusive, although likely the northernmost West will see precipitation increases while the southernmost West sees declines. However, most of the region lies in a broad area where some climate models project precipitation increases while others project declines, so that only increases in precipitation uncertainties can be projected with any confidence. Changes in annual and seasonal hydrographs are likely to challenge water managers, users, and attempts to protect or restore environmental flows, even where annual volumes change little. Other impacts from climate change (e.g., floods and water-quality changes) are poorly understood and will likely be location dependent.

  9. Monitoring and condition-based maintenance with abrupt change in a system's deterioration rate

    Science.gov (United States)

    Fouladirad, Mitra; Grall, Antoine

    2015-09-01

    In this paper, the maintenance of a system which undergoes a change in its deterioration rate is considered. The time of change of regime and the parameters after the change are unknown. To deal with unknown change time and unknown parameters, a detection procedure based on a suitable online change detection algorithm is used. The paper proposes a maintenance decision rule versus detection policy in order to minimise the long-run average maintenance cost, and the performances of this policy are studied through numerical implementations.

  10. Changing the intellectual climate

    Science.gov (United States)

    Castree, Noel; Adams, William M.; Barry, John; Brockington, Daniel; Büscher, Bram; Corbera, Esteve; Demeritt, David; Duffy, Rosaleen; Felt, Ulrike; Neves, Katja; Newell, Peter; Pellizzoni, Luigi; Rigby, Kate; Robbins, Paul; Robin, Libby; Rose, Deborah Bird; Ross, Andrew; Schlosberg, David; Sörlin, Sverker; West, Paige; Whitehead, Mark; Wynne, Brian

    2014-09-01

    Calls for more broad-based, integrated, useful knowledge now abound in the world of global environmental change science. They evidence many scientists' desire to help humanity confront the momentous biophysical implications of its own actions. But they also reveal a limited conception of social science and virtually ignore the humanities. They thereby endorse a stunted conception of 'human dimensions' at a time when the challenges posed by global environmental change are increasing in magnitude, scale and scope. Here, we make the case for a richer conception predicated on broader intellectual engagement and identify some preconditions for its practical fulfilment. Interdisciplinary dialogue, we suggest, should engender plural representations of Earth's present and future that are reflective of divergent human values and aspirations. In turn, this might insure publics and decision-makers against overly narrow conceptions of what is possible and desirable as they consider the profound questions raised by global environmental change.

  11. Millennial scale precipitation changes over Easter Island (Southern Pacific) during MIS 3: Inter-hemispheric connections during North Atlantic abrupt cold events

    Science.gov (United States)

    Margalef, Olga; Cacho, Isabel; Pla-Rabes, Sergi; Cañellas-Boltà, Núria; Pueyo, Juan Jose; Sáez, Alberto; Valero-Garcés, Blas L.; Giralt, Santiago

    2013-04-01

    Hemisphere have been abrupt in response to the MIS 3 climate variability, a pattern which is in contrast to the typical gradual changes shown by several southern hemisphere records. This points to a very rapid atmospheric reorganization at low and medium latitudes in front to a more progressive oceanic heat redistribution lead by the bipolar seesaw.

  12. Assessing urban climate change resilience

    Science.gov (United States)

    Voskaki, Asimina

    2016-04-01

    Recent extreme weather events demonstrate that many urban environments are vulnerable to climate change impacts and as a consequence designing systems for future climate seems to be an important parameter in sustainable urban planning. The focus of this research is the development of a theoretical framework to assess climate change resilience in urban environments. The methodological approach used encompasses literature review, detailed analysis, and combination of data, and the development of a series of evaluation criteria, which are further analyzed into a list of measures. The choice of the specific measures is based upon various environmental, urban planning parameters, social, economic and institutional features taking into consideration key vulnerabilities and risk associated with climate change. The selected criteria are further prioritized to incorporate into the evaluation framework the level of importance of different issues towards a climate change resilient city. The framework could support decision making as regards the ability of an urban system to adapt. In addition it gives information on the level of adaptation, outlining barriers to sustainable urban planning and pointing out drivers for action and reaction.

  13. Making Sense of Climate Change

    DEFF Research Database (Denmark)

    Blichfeldt, Nikolaj Vendelbo

    The thesis is an ethnographic description of a climate change mitigation campaign among retirees in the urban residential community Dongping Lane in central Hangzhou, and an examination of local understandings of connections between everyday life in the community and global climate change...... is conceived as part of wider state-sponsored efforts to foster civilized behavior and a sense of belonging to the residential community among urban citizens in China. The campaigners connect unspectacular everyday consumer practices with climate change and citizenship by showing that among them, making...... health, comfort and convenience. Conceived as pleasurable, easy to approach, and good for the body, low-carbon life comes to be seen as a series of hobby-like activities that residents can engage in as part of their quests for good and meaningful lives in old age. Campaigners engage engage in trans-historical...

  14. Climate change and game theory.

    Science.gov (United States)

    Wood, Peter John

    2011-02-01

    This paper examines the problem of achieving global cooperation to reduce greenhouse gas emissions. Contributions to this problem are reviewed from noncooperative game theory, cooperative game theory, and implementation theory. We examine the solutions to games where players have a continuous choice about how much to pollute, as well as games where players make decisions about treaty participation. The implications of linking cooperation on climate change with cooperation on other issues, such as trade, are also examined. Cooperative and noncooperative approaches to coalition formation are investigated in order to examine the behavior of coalitions cooperating on climate change. One way to achieve cooperation is to design a game, known as a mechanism, whose equilibrium corresponds to an optimal outcome. This paper examines some mechanisms that are based on conditional commitments, and their policy implications. These mechanisms could make cooperation on climate change mitigation more likely.

  15. Position Statement On Climate Change.

    Science.gov (United States)

    2016-05-01

    The North Carolina Environmental Justice Network (NCEJN), a coalition of grassroots organizations, developed a statement to explain our environmental justice perspective on climate change to predominantly white environmental groups that seek to partner with us. NCEJN opposes strategies that reduce greenhouse emissions while maintaining or magnifying existing social, economic, and environmental injustices. Wealthy communities that consume a disproportionate share of resources avoid the most severe consequences of their consumption by displacing pollution on communities of color and low income. Therefore, the success of climate change activism depends on building an inclusive movement based on principles of racial, social and economic justice, and self-determination for all people.

  16. [Air quality and climate change].

    Science.gov (United States)

    Loft, Steffen

    2009-10-26

    Air quality, health and climate change are closely connected. Ozone depends on temperature and the greenhouse gas methane from cattle and biomass. Pollen presence depends on temperature and CO2. The effect of climate change on particulate air pollution is complex, but the likely net effect is greater health risks. Reduction of greenhouse-gas emissions by reduced livestock production and use of combustion for energy production, transport and heating will also improve air quality. Energy savings in buildings and use of CO2 neutral fuels should not deteriorate indoor and outdoor air quality.

  17. Climate Change: A Regional Perspective

    OpenAIRE

    Inter-American Development Bank (IDB); Economic Commission for Latin America and the Caribbean (ECLAC)

    2010-01-01

    The purpose of this document is to contribute to the ongoing discussion on climate change in light of the available evidence on the possible channels of transmission of the economic impact of this phenomenon and the results of the latest session of the Conference of the Parties to the United Nations Framework Convention on Climate Change (COP 15), held in Copenhagen from 7 to 18 December 2009. This document has been prepared, at the request of the Government of Mexico, by the Economic Commiss...

  18. Maritime Archaeology and Climate Change: An Invitation

    Science.gov (United States)

    Wright, Jeneva

    2016-08-01

    Maritime archaeology has a tremendous capacity to engage with climate change science. The field is uniquely positioned to support climate change research and the understanding of past human adaptations to climate change. Maritime archaeological data can inform on environmental shifts and submerged sites can serve as an important avenue for public outreach by mobilizing public interest and action towards understanding the impacts of climate change. Despite these opportunities, maritime archaeologists have not fully developed a role within climate change science and policy. Moreover, submerged site vulnerabilities stemming from climate change impacts are not yet well understood. This article discusses potential climate change threats to maritime archaeological resources, the challenges confronting cultural resource managers, and the contributions maritime archaeology can offer to climate change science. Maritime archaeology's ability to both support and benefit from climate change science argues its relevant and valuable place in the global climate change dialogue, but also reveals the necessity for our heightened engagement.

  19. Maritime Archaeology and Climate Change: An Invitation

    Science.gov (United States)

    Wright, Jeneva

    2016-12-01

    Maritime archaeology has a tremendous capacity to engage with climate change science. The field is uniquely positioned to support climate change research and the understanding of past human adaptations to climate change. Maritime archaeological data can inform on environmental shifts and submerged sites can serve as an important avenue for public outreach by mobilizing public interest and action towards understanding the impacts of climate change. Despite these opportunities, maritime archaeologists have not fully developed a role within climate change science and policy. Moreover, submerged site vulnerabilities stemming from climate change impacts are not yet well understood. This article discusses potential climate change threats to maritime archaeological resources, the challenges confronting cultural resource managers, and the contributions maritime archaeology can offer to climate change science. Maritime archaeology's ability to both support and benefit from climate change science argues its relevant and valuable place in the global climate change dialogue, but also reveals the necessity for our heightened engagement.

  20. Case grows for climate change

    Energy Technology Data Exchange (ETDEWEB)

    Hileman, B.

    1999-08-09

    In the four years since the IPCC stated that 'the balance of evidence suggests a discernible human influence on global climate', evidence for anomalous warming has become more compelling, and as a result scientists have become more concerned that human-induced climate change has already arrived. The article summarises recent extra evidence on global temperatures, carbon dioxide measurements, ice shelf breakup, coral bleaching, unstable climates and improved climate models. At the time of the Kyoto conference, the US became keen on the idea that enhancing forest and soil carbon sequestration was a good way to offset emissions reduction targets. Congress is however under the opinion on that the Kyoto protocol presents a threat to the US economy, and senate is very unlikely to ratify the protocol during the Clinton Administration. The debate as to whether the US government should mandate major emission reduction or wait for more scientific certainty may continue for a number of years, but, growing concern of scientists and the public for the harmful effects of climate change may cause a change. 4 figs., 8 photos.

  1. A New Method to Measure Electroosmotic Flow Mobility of Capillary Electrophoresis by Abrupt Change of Current De-noising via Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    LI,Qian-Feng; ZHANG,Xiao-Yun; ZHANG,Hong-Yi; CHEN,Xing-Guo; LIU,Man-Cang; HU,Zhi-De

    2001-01-01

    The electroosmotic flow mobility has been measured by the combination of monitoring the change in electric current dur ing electrophoretic run and operating the wavelet transform. Once the sample solvent zone with different ionic stenggth from background electrolyte migrated from the capillary, a sudden change in current could be observed from the ekectric current record of time history. The exact time (in the middle of abrupt range) corresponding to the abrupt change in cur rent was determined by wavelet transform. This work showed posed method was in a good agreement with the neutral mark er method commonly used.

  2. Abrupt change point detection of annual maximum precipitation using fused lasso

    Science.gov (United States)

    Jeon, Jong-June; Sung, Jang Hyun; Chung, Eun-Sung

    2016-07-01

    Because the widely used Bayesian change point analysis (BCPA) is generally applied to the normal distribution, it cannot be freely used to the annual maximum precipitations (AMP) in South Korea. Therefore, this study proposed the fused lasso penalty function to detect the change point of AMP which can be generally fitted by using the Generalized Extreme Value (GEV) distribution in South Korea. First, four numerical experiments are conducted to compare the detection performances between BCPA and fused lasso method. As a result, fused lasso shows the superiority of the data generated by GEV distribution having skewness. The fused lasso method is applied to 63 weather stations in South Korea and then 17 stations having any change points from BCPA and the GEV fused lasso are analyzed. Similar to the numerical analyses, the GEV fused lasso method can delicately detect the change point of AMPs. After the change point, the means of AMPs did not go back to the previous. Alternately, BCPA can be stated to find variation points not change points because the means returned to their original values as time progressed. Therefore, it can be concluded that the GEV fused lasso method detects the change points of non-stationary AMPs of South Korea. This study can be extended to more extreme distributions for various meteorological variables.

  3. The origin of climate changes.

    Science.gov (United States)

    Delecluse, P

    2008-08-01

    Investigation on climate change is coordinated by the Intergovernmental Panel on Climate Change (IPCC), which has the delicate task of collecting recent knowledge on climate change and the related impacts of the observed changes, and then developing a consensus statement from these findings. The IPCC's last review, published at the end of 2007, summarised major findings on the present climate situation. The observations show a clear increase in the temperature of the Earth's surface and the oceans, a reduction in the land snow cover, and melting of the sea ice and glaciers. Numerical modelling combined with statistical analysis has shown that this warming trend is very likely the signature of increasing emissions of greenhouse gases linked with human activities. Given the continuing social and economic development around the world, the IPCC emission scenarios forecast an increasing greenhouse effect, at least until 2050 according to the most optimistic models. The model ensemble predicts a rising temperature that will reach dangerous levels for the biosphere and ecosystems within this century. Hydrological systems and the potential significant impacts of these systems on the environment are also discussed. Facing this challenging future, societies must take measures to reduce emissions and work on adapting to an inexorably changing environment. Present knowledge is sufficientto start taking action, but a stronger foundation is needed to ensure that pertinent long-term choices are made that will meet the demands of an interactive and rapidly evolving world.

  4. A Review of the Detection Methods for Climate Regime Shifts

    Directory of Open Access Journals (Sweden)

    Qunqun Liu

    2016-01-01

    Full Text Available An abrupt climate change means that the climate system shifts from a steady state to another steady state. Study on the phenomenon and theory of the abrupt climate change is a new research field of modern climatology, and it is of great significance for the prediction of future climate change. The climate regime shift is one of the most common forms of abrupt climate change, which mainly refers to the statistical significant changes on the variable of climate system at one time scale. These detection methods can be roughly divided into five categories based on different types of abrupt changes, namely, abrupt mean value change, abrupt variance change, abrupt frequency change, abrupt probability density change, and the multivariable analysis. The main research progress of abrupt climate change detection methods is reviewed. What is more, some actual applications of those methods in observational data are provided. With the development of nonlinear science, many new methods have been presented for detecting an abrupt dynamic change in recent years, which is useful supplement for the abrupt change detection methods.

  5. Changing habits, changing climate : a foundation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Enright, W. [Canadian Inst. of Child Health, Ottawa, ON (Canada)

    2001-03-01

    If Canada intends to meet its greenhouse gas reduction target of 6 per cent below 1990 levels, a fundamental shift in energy use by Canadians is required. The health sector will also be required to change. Global climate change is expected to affect regions differently, some might get wetter, some might get warmer, and others still might get colder. Climate changes will influence a number of health determinants: the geographical range of disease organisms and vectors; temperature extremes and violent weather events; air, food and water quality; the stability of ecosystems. There is a requirement to strongly regulate the emissions of carbon dioxide, methane and other greenhouse gases to limit health risks. Increased air pollution could negatively affect large numbers of people, especially asthma sufferers and people suffering from chronic respiratory ailments and cardiovascular diseases. Changes in precipitation and temperature could increase insect-borne diseases. Water sources could be badly affected by drought, flooding or increased glacial runoff. The thinning of the ozone layer could result in additional skin cancers, impaired vision and other diseases. The document explores the various impacts resulting from climate change. A chapter is devoted to each topic: air pollution, temperature extremes, extreme weather events, vector borne diseases, drought and increased evaporation, food supply and ecosystem range, sea level rise, stratospheric ozone depletion and describes the health impacts. In addition, a chapter deals with aboriginal communities. The topic of environmental refugees is discussed, followed by an historical perspective into climate change policy in Canada. The author concludes with adaptation measures. Further emphasis must be placed on priority topics such as the estimation of future emissions and modelling of climate processes. refs., tabs., figs.

  6. Arctic climate change in NORKLIMA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The NORKLIMA programme is the national Norwegian initiative on climate research established for the period 2004-2013. The programme seeks to generate key knowledge about climate trends, the impacts of climate change, and how Norway can adapt to these changes. The NORKLIMA programme also encompasses research on instruments and policies for reducing emissions. Large-scale Programmes As part of the effort to meet national research-policy priorities, the Research Council has established a special funding instrument called the Large-scale Programmes. This initiative is designed to build long-term knowledge in order to encourage innovation and enhance value creation as well as to help find solutions to important challenges facing society.(Author)

  7. Abrupt plant physiological changes in southern New Zealand at the termination of the Mi-1 event reflect shifts in hydroclimate and pCO2

    Science.gov (United States)

    Reichgelt, Tammo; D'Andrea, William J.; Fox, Bethany R. S.

    2016-12-01

    A rise in atmospheric CO2 is believed to be necessary for the termination of large-scale glaciations. Although the Antarctic Ice Sheet is estimated to have melted from ∼125% to ∼50% its modern size, there is thus far no evidence for an increase in atmospheric CO2 associated with the Mi-1 glacial termination in the earliest Miocene. Here, we present evidence from a high-resolution terrestrial record of leaf physiological change in southern New Zealand for an abrupt increase in atmospheric CO2 coincident with the termination of the Mi-1 glaciation and lasting approximately 20 kyr. Quantitative pCO2 estimates, made using a leaf gas exchange model, suggest that atmospheric CO2 levels may have doubled during this period, from 516 ± 111ppm to 1144 ± 410ppm, and subsequently returned back to 425 ± 53ppm. The 20-kyr interval with high pCO2 estimates is also associated with a period of increased moisture supply to southern New Zealand, inferred from carbon and hydrogen isotopes of terrestrial leaf waxes. The results provide the first high-resolution record of terrestrial environmental change at the Oligocene/Miocene boundary, document a ∼20 kyr interval of elevated pCO2 and increased local moisture availability, and provide insight into ecosystem response to a major orbitally driven climatic transition.

  8. Annual proxy data from Lago Grande di Monticchio (southern Italy) contributing to chronological constraints and abrupt climatic oscillations between 76 and 112 ka

    Science.gov (United States)

    Martin-Puertas, C.; Brauer, A.; Wulf, S.; Ott, F.; Lauterbach, S.; Dulski, P.

    2014-06-01

    We present annual sedimentological proxies and sub-annual element scanner data from the Lago Grande di Monticchio (MON) sediment record for the sequence 76-112 ka, which, combined with the decadal to centennial resolved pollen assemblage, allow a comprehensive reconstruction of six major abrupt cold and relatively humid spells (MON 1-6) in the central Mediterranean during early phase of the last glaciation. These climatic oscillations are defined by intervals of thicker varves and high Ti-counts and coincide with episodes of forest depletion interpreted as cold and wet oscillations. Based on the independent and slightly revised MON-2014 varve chronology (76-112 ka), a detailed comparison with the Greenland ice-core δ18O record (NGRIP) and northern Alps speleothem δ18O data (NALPS) is presented. Based on visual inspection of major changes in the proxy data, MON 2-6 are suggested to correlate with GS 25-20. MON 1 (Woillard event), the first and shortest cooling spell in the Mediterranean after a long phase of stable interglacial conditions, has no counterpart in the Greenland ice core, but coincides with the lowest isotope values at the end of the gradual decrease in δ18O in NGRIP during the second half of the GI 25. MON 3 is the least pronounced cold spell and shows gradual transitions, whereas its NGRIP counterpart GS 24 is characterized by sharp changes in the isotope records. MON 2 and MON 4 are the longest most pronounced oscillations in the MON sediments in good agreement with their counterparts in the ice and spelethem records. The length of MON 4 (correlating with GS 22) support the duration of this stadial proposed by the NALPS timescales and suggests ca. 500 yr longer duration than calculated by GICC05 and AICC2012, which would confirm a~possible underestimation in the ice-core. Absolute dating of the cold spells occurring from 112 to 100 ka (MON 1-3) in the MON-2014 chronology is in good agreement with the GICC05 and NALPS timescales but the younger

  9. Annual proxy data from Lago Grande di Monticchio (southern Italy contributing to chronological constraints and abrupt climatic oscillations between 76 and 112 ka

    Directory of Open Access Journals (Sweden)

    C. Martin-Puertas

    2014-06-01

    Full Text Available We present annual sedimentological proxies and sub-annual element scanner data from the Lago Grande di Monticchio (MON sediment record for the sequence 76–112 ka, which, combined with the decadal to centennial resolved pollen assemblage, allow a comprehensive reconstruction of six major abrupt cold and relatively humid spells (MON 1–6 in the central Mediterranean during early phase of the last glaciation. These climatic oscillations are defined by intervals of thicker varves and high Ti-counts and coincide with episodes of forest depletion interpreted as cold and wet oscillations. Based on the independent and slightly revised MON-2014 varve chronology (76–112 ka, a detailed comparison with the Greenland ice-core δ18O record (NGRIP and northern Alps speleothem δ18O data (NALPS is presented. Based on visual inspection of major changes in the proxy data, MON 2–6 are suggested to correlate with GS 25–20. MON 1 (Woillard event, the first and shortest cooling spell in the Mediterranean after a long phase of stable interglacial conditions, has no counterpart in the Greenland ice core, but coincides with the lowest isotope values at the end of the gradual decrease in δ18O in NGRIP during the second half of the GI 25. MON 3 is the least pronounced cold spell and shows gradual transitions, whereas its NGRIP counterpart GS 24 is characterized by sharp changes in the isotope records. MON 2 and MON 4 are the longest most pronounced oscillations in the MON sediments in good agreement with their counterparts in the ice and spelethem records. The length of MON 4 (correlating with GS 22 support the duration of this stadial proposed by the NALPS timescales and suggests ca. 500 yr longer duration than calculated by GICC05 and AICC2012, which would confirm a~possible underestimation in the ice-core. Absolute dating of the cold spells occurring from 112 to 100 ka (MON 1–3 in the MON-2014 chronology is in good agreement with the GICC05 and NALPS

  10. Climate change and trace gases.

    Science.gov (United States)

    Hansen, James; Sato, Makiko; Kharecha, Pushker; Russell, Gary; Lea, David W; Siddall, Mark

    2007-07-15

    Palaeoclimate data show that the Earth's climate is remarkably sensitive to global forcings. Positive feedbacks predominate. This allows the entire planet to be whipsawed between climate states. One feedback, the 'albedo flip' property of ice/water, provides a powerful trigger mechanism. A climate forcing that 'flips' the albedo of a sufficient portion of an ice sheet can spark a cataclysm. Inertia of ice sheet and ocean provides only moderate delay to ice sheet disintegration and a burst of added global warming. Recent greenhouse gas (GHG) emissions place the Earth perilously close to dramatic climate change that could run out of our control, with great dangers for humans and other creatures. Carbon dioxide (CO2) is the largest human-made climate forcing, but other trace constituents are also important. Only intense simultaneous efforts to slow CO2 emissions and reduce non-CO2 forcings can keep climate within or near the range of the past million years. The most important of the non-CO2 forcings is methane (CH4), as it causes the second largest human-made GHG climate forcing and is the principal cause of increased tropospheric ozone (O3), which is the third largest GHG forcing. Nitrous oxide (N2O) should also be a focus of climate mitigation efforts. Black carbon ('black soot') has a high global warming potential (approx. 2000, 500 and 200 for 20, 100 and 500 years, respectively) and deserves greater attention. Some forcings are especially effective at high latitudes, so concerted efforts to reduce their emissions could preserve Arctic ice, while also having major benefits for human health, agricultural productivity and the global environment.

  11. Climate change, zoonoses and India.

    Science.gov (United States)

    Singh, B B; Sharma, R; Gill, J P S; Aulakh, R S; Banga, H S

    2011-12-01

    Economic trends have shaped our growth and the growth of the livestock sector, but atthe expense of altering natural resources and systems in ways that are not always obvious. Now, however, the reverse is beginning to happen, i.e. environmental trends are beginning to shape our economy and health status. In addition to water, air and food, animals and birds play a pivotal role in the maintenance and transmission of important zoonotic diseases in nature. It is generally considered that the prevalence of vector-borne and waterborne zoonoses is likely to increase in the coming years due to the effects of global warming in India. In recent years, vector-borne diseases have emerged as a serious public health problem in countries of the South-East Asia region, including India. Vector-borne zoonoses now occur in epidemic form almost on an annual basis, causing considerable morbidity and mortality. New reservoir areas of cutaneous leishmaniosis in South India have been recognised, and the role of climate change in its re-emergence warrants further research, as does the role of climate change in the ascendancy of waterborne and foodborne illness. Similarly, climate change that leads to warmer and more humid conditions may increase the risk of transmission of airborne zoonoses, and hot and drier conditions may lead to a decline in the incidence of disease(s). The prevalence of these zoonotic diseases and their vectors and the effect of climate change on important zoonoses in India are discussed in this review.

  12. Hydrological response to climate change

    NARCIS (Netherlands)

    Yan, Dan; Werners, S.E.; Ludwig, Fulco; Huang, He Qing

    2015-01-01

    Study region: The Pearl River, located in the south of China, is the second largest river in China in terms of streamflow. Study focus: The study aims to assess the impact of climate change on seasonal discharge and extreme flows. For the assessment we use the variable infiltration capacity (VIC)

  13. Indigenous Peoples and Climate Change

    Directory of Open Access Journals (Sweden)

    Shelton H. Davis

    2010-05-01

    Full Text Available There has been a growing attention on the need to take into account the effects of global climate change. This is particularly so with respect to the increasing amount of green house gas emissions from the Untied States and Europe affecting poor peoples, especially those in developing countries. In 2003, for example, the experts of several international development agencies, including the World Bank, prepared a special report titled “Poverty and Climate Change: Reducing the Vulnerability of the Poor through Adaptation” (OECD 2003. This report followed the Eighth Session of the Conference of Parties (COP8 to the United Nations Framework Convention on Climate Change (UNFCCC in New Delhi, India in October 2002. It showed that poverty reduction is not only one of the major challenges of the 21st century, but also that climate change is taking place in many developing countries and is increasingly affecting, in a negative fashion, both the economic conditions and the health of poor people and their communities.

  14. A Lesson on Climate Change.

    Science.gov (United States)

    Lewis, Jim

    This cooperative learning activity, for grades 7-12, promotes critical thinking skills within the context of learning about the causes and effects of climate change. Objectives include: (1) understanding factors that reduce greenhouse gases; (2) understanding the role of trees in reducing greenhouse gases; (3) identifying foods that produce…

  15. Climate change primer for respirologists.

    Science.gov (United States)

    Takaro, Tim K; Henderson, Sarah B

    2015-01-01

    Climate change is already affecting the cardiorespiratory health of populations around the world, and these impacts are expected to increase. The present overview serves as a primer for respirologists who are concerned about how these profound environmental changes may affect their patients. The authors consider recent peer-reviewed literature with a focus on climate interactions with air pollution. They do not discuss in detail cardiorespiratory health effects for which the potential link to climate change is poorly understood. For example, pneumonia and influenza, which affect >500 million people per year, are not addressed, although clear seasonal variation suggests climate-related effects. Additionally, large global health impacts in low-resource countries, including migration precipitated by environmental change, are omitted. The major cardiorespiratory health impacts addressed are due to heat, air pollution and wildfires, shifts in allergens and infectious diseases along with respiratory impacts from flooding. Personal and societal choices about carbon use and fossil energy infrastructure should be informed by their impacts on health, and respirologists can play an important role in this discussion.

  16. Climate change and allergic disease.

    Science.gov (United States)

    Shea, Katherine M; Truckner, Robert T; Weber, Richard W; Peden, David B

    2008-09-01

    Climate change is potentially the largest global threat to human health ever encountered. The earth is warming, the warming is accelerating, and human actions are largely responsible. If current emissions and land use trends continue unchecked, the next generations will face more injury, disease, and death related to natural disasters and heat waves, higher rates of climate-related infections, and wide-spread malnutrition, as well as more allergic and air pollution-related morbidity and mortality. This review highlights links between global climate change and anticipated increases in prevalence and severity of asthma and related allergic disease mediated through worsening ambient air pollution and altered local and regional pollen production. The pattern of change will vary regionally depending on latitude, altitude, rainfall and storms, land-use patterns, urbanization, transportation, and energy production. The magnitude of climate change and related increases in allergic disease will be affected by how aggressively greenhouse gas mitigation strategies are pursued, but at best an average warming of 1 to 2 degrees C is certain this century. Thus, anticipation of a higher allergic disease burden will affect clinical practice as well as public health planning. A number of practical primary and secondary prevention strategies are suggested at the end of the review to assist in meeting this unprecedented public health challenge.

  17. Climate Change: Evidence and Causes

    Science.gov (United States)

    Wolff, Eric

    2014-01-01

    The fundamentals of climate change are well established: greenhouse gases warm the planet; their concentrations in the atmosphere are increasing; Earth has warmed, and is going to continue warming with a range of impacts. This article summarises the contents of a recent publication issued by the UK's Royal Society and the US National Academy…

  18. Climate Change: Evidence and Causes

    Science.gov (United States)

    Wolff, Eric

    2014-01-01

    The fundamentals of climate change are well established: greenhouse gases warm the planet; their concentrations in the atmosphere are increasing; Earth has warmed, and is going to continue warming with a range of impacts. This article summarises the contents of a recent publication issued by the UK's Royal Society and the US National Academy of…

  19. Students' evaluations about climate change

    Science.gov (United States)

    Lombardi, Doug; Brandt, Carol B.; Bickel, Elliot S.; Burg, Colin

    2016-05-01

    Scientists regularly evaluate alternative explanations of phenomena and solutions to problems. Students should similarly engage in critical evaluation when learning about scientific and engineering topics. However, students do not often demonstrate sophisticated evaluation skills in the classroom. The purpose of the present study was to investigate middle school students' evaluations when confronted with alternative explanations of the complex and controversial topic of climate change. Through a qualitative analysis, we determined that students demonstrated four distinct categories of evaluation when writing about the connections between evidence and alternative explanations of climate change: (a) erroneous evaluation, (b) descriptive evaluation, (c) relational evaluation, and (d) critical evaluation. These categories represent different types of evaluation quality. A quantitative analysis revealed that types of evaluation, along with plausibility perceptions about the alternative explanations, were significant predictors of postinstructional knowledge about scientific principles underlying the climate change phenomenon. Specifically, more robust evaluations and greater plausibility toward the scientifically accepted model of human-induced climate change predicted greater knowledge. These findings demonstrate that instruction promoting critical evaluation and plausibility appraisal may promote greater understanding of socio-scientific topics and increased use of scientific thinking when considering alternative explanations, as is called for by recent science education reform efforts.

  20. The Science of Climate Change

    Science.gov (United States)

    Oppenheimer, Michael; Anttila-Hughes, Jesse K.

    2016-01-01

    Michael Oppenheimer and Jesse Anttila-Hughes begin with a primer on how the greenhouse effect works, how we know that Earth is rapidly getting warmer, and how we know that the recent warming is caused by human activity. They explain the sources of scientific knowledge about climate change as well as the basis for the models scientists use to…

  1. Climate benefits of changing diet

    NARCIS (Netherlands)

    Stehfest, E.; Bouwman, A.F.; Vuuren, van D.P.; Elzen, M.; Kabat, P.

    2009-01-01

    Climate change mitigation policies tend to focus on the energy sector, while the livestock sector receives surprisingly little attention, despite the fact that it accounts for 18% of the greenhouse gas emissions and for 80% of total anthropogenic land use. From a dietary perspective, new insights in

  2. The Whiteness of Climate Change

    DEFF Research Database (Denmark)

    Jensen, Lars

    2011-01-01

    This article examines two major debates in contemporary Australian discourses on the nation: climate change and whiteness studies. It is primarily concerned with establishing a framework for connecting the two discourses, and in that process it raises pivotal questions about how narratives about...

  3. Climate Change: Evidence and Causes

    Science.gov (United States)

    Wolff, Eric

    2014-01-01

    The fundamentals of climate change are well established: greenhouse gases warm the planet; their concentrations in the atmosphere are increasing; Earth has warmed, and is going to continue warming with a range of impacts. This article summarises the contents of a recent publication issued by the UK's Royal Society and the US National Academy of…

  4. The Whiteness of Climate Change

    DEFF Research Database (Denmark)

    Jensen, Lars

    2011-01-01

    This article examines two major debates in contemporary Australian discourses on the nation: climate change and whiteness studies. It is primarily concerned with establishing a framework for connecting the two discourses, and in that process it raises pivotal questions about how narratives about...

  5. Abrupt vegetation change after the Late Quaternary megafaunal extinction in southeastern Australia

    NARCIS (Netherlands)

    Lopes dos Santos, R.A.; De Deckker, P.; Hopmans, E.C.; Magee, J.W.; Mets, A.; Sinninghe Damsté, J.S.; Schouten, S.

    2013-01-01

    A substantial extinction of megafauna occurred in Australia between 50 and 45 kyr ago(1,2), a period that coincides with human colonization of Australia(3). Large shifts in vegetation also occurred around this time, but it is unclear whether the vegetation changes were driven by the human use of fir

  6. Changing Climates @ Colorado State: 100 (Multidisciplinary) Views of Climate Change

    Science.gov (United States)

    Campbell, S.; Calderazzo, J.; Changing Climates, Cmmap Education; Diversity Team

    2011-12-01

    We would like to talk about a multidisciplinary education and outreach program we co-direct at Colorado State University, with support from an NSF-funded STC, CMMAP, the Center for Multiscale Modeling of Atmospheric Processes. We are working to raise public literacy about climate change by providing information that is high quality, up to date, thoroughly multidisciplinary, and easy for non-specialists to understand. Our primary audiences are college-level students, their teachers, and the general public. Our motto is Climate Change is Everybody's Business. To encourage and help our faculty infuse climate-change content into their courses, we have organized some 115 talks given by as many different speakers-speakers drawn from 28 academic departments, all 8 colleges at CSU, and numerous other entities from campus, the community, and farther afield. We began with a faculty-teaching-faculty series and then broadened our attentions to the whole campus and surrounding community. Some talks have been for narrowly focused audiences such as extension agents who work on energy, but most are for more eclectic groups of students, staff, faculty, and citizens. We count heads at most events, and our current total is roughly 6,000. We have created a website (http://changingclimates.colostate.edu) that includes videotapes of many of these talks, short videos we have created, and annotated sources that we judge to be accurate, interesting, clearly written, and aimed at non-specialists, including books, articles and essays, websites, and a few items specifically for college teachers (such as syllabi). Pages of the website focus on such topics as how the climate works / how it changes; what's happening / what might happen; natural ecosystems; agriculture; impacts on people; responses from ethics, art, literature; communication; daily life; policy; energy; and-pulling all the pieces together-the big picture. We have begun working on a new series of very short videos that can be

  7. Fast Vegetational Responses to Late-Glacial Climate Change

    Science.gov (United States)

    Williams, J. W.; Post, D. M.; Cwynar, L. C.; Lotter, A. F.; Levesque, A. J.

    2001-12-01

    How rapidly can natural ecosystems respond to rapid climate change? This question can be addressed by studying paired paleoecological and paleoclimatological records spanning the last deglaciation. Between 16 and 10 ka, abrupt climatic oscillations (e.g. Younger Dryas, Gerzensee/Killarney Oscillations) interrupted the general warming trend. Rates of climate change during these events were as fast or faster than projected rates of change for this century. We compiled a dozen high-resolution lacustrine records in North America and Europe with a pollen record and independent climatic proxy, a clear Younger Dryas signal, and good age control. Cross-correlation analysis suggests that vegetation responded rapidly to late-glacial climate change, with significant changes in vegetation composition occurring within the lifespan of individual trees. At all sites, vegetation lagged climate by less than 200 years, and at two-thirds of the sites, the initial vegetational response occurred within 100 years. The finding of rapid vegetational responses is consistent across sites and continents, and is similar to the 100-200 year response times predicted by gap-scale forest models. Likely mechanisms include 1) increased susceptibility of mature trees to disturbances such as fire, wind, and disease, thereby opening up gaps for colonization, 2) the proximity of these sites to late-glacial treeline, where climate may directly control plant population densities and range limits, 3) the presence of herbaceous taxa with short generation times in these plant communities, and 4) rapid migration due to rare long-distance seed dispersals. Our results are consistent with reports that plant ranges are already shifting in response to recent climate change, and suggest that these shifts will persist for the next several centuries. Widespread changes in plant distributions may affect surface-atmosphere interactions and will challenge attempts to manage ecosystems and conserve biodiversity.

  8. Climate Change and Intertidal Wetlands

    Directory of Open Access Journals (Sweden)

    Pauline M. Ross

    2013-03-01

    Full Text Available Intertidal wetlands are recognised for the provision of a range of valued ecosystem services. The two major categories of intertidal wetlands discussed in this contribution are saltmarshes and mangrove forests. Intertidal wetlands are under threat from a range of anthropogenic causes, some site-specific, others acting globally. Globally acting factors include climate change and its driving cause—the increasing atmospheric concentrations of greenhouse gases. One direct consequence of climate change will be global sea level rise due to thermal expansion of the oceans, and, in the longer term, the melting of ice caps and glaciers. The relative sea level rise experienced at any one locality will be affected by a range of factors, as will the response of intertidal wetlands to the change in sea level. If relative sea level is rising and sedimentation within intertidal wetlands does not keep pace, then there will be loss of intertidal wetlands from the seaward edge, with survival of the ecosystems only possible if they can retreat inland. When retreat is not possible, the wetland area will decline in response to the “squeeze” experienced. Any changes to intertidal wetland vegetation, as a consequence of climate change, will have flow on effects to biota, while changes to biota will affect intertidal vegetation. Wetland biota may respond to climate change by shifting in distribution and abundance landward, evolving or becoming extinct. In addition, impacts from ocean acidification and warming are predicted to affect the fertilisation, larval development, growth and survival of intertidal wetland biota including macroinvertebrates, such as molluscs and crabs, and vertebrates such as fish and potentially birds. The capacity of organisms to move and adapt will depend on their life history characteristics, phenotypic plasticity, genetic variability, inheritability of adaptive characteristics, and the predicted rates of environmental change.

  9. Climate change and intertidal wetlands.

    Science.gov (United States)

    Ross, Pauline M; Adam, Paul

    2013-03-19

    Intertidal wetlands are recognised for the provision of a range of valued ecosystem services. The two major categories of intertidal wetlands discussed in this contribution are saltmarshes and mangrove forests. Intertidal wetlands are under threat from a range of anthropogenic causes, some site-specific, others acting globally. Globally acting factors include climate change and its driving cause-the increasing atmospheric concentrations of greenhouse gases. One direct consequence of climate change will be global sea level rise due to thermal expansion of the oceans, and, in the longer term, the melting of ice caps and glaciers. The relative sea level rise experienced at any one locality will be affected by a range of factors, as will the response of intertidal wetlands to the change in sea level. If relative sea level is rising and sedimentation within intertidal wetlands does not keep pace, then there will be loss of intertidal wetlands from the seaward edge, with survival of the ecosystems only possible if they can retreat inland. When retreat is not possible, the wetland area will decline in response to the "squeeze" experienced. Any changes to intertidal wetland vegetation, as a consequence of climate change, will have flow on effects to biota, while changes to biota will affect intertidal vegetation. Wetland biota may respond to climate change by shifting in distribution and abundance landward, evolving or becoming extinct. In addition, impacts from ocean acidification and warming are predicted to affect the fertilisation, larval development, growth and survival of intertidal wetland biota including macroinvertebrates, such as molluscs and crabs, and vertebrates such as fish and potentially birds. The capacity of organisms to move and adapt will depend on their life history characteristics, phenotypic plasticity, genetic variability, inheritability of adaptive characteristics, and the predicted rates of environmental change.

  10. Science Matters Podcast: Climate Change Research

    Science.gov (United States)

    Listen to a podcast with Dr. Andy Miller, the Associate Director for Climate for the Agency's Air, Climate, and Energy Research Program, as he answers questions about climate change research, or read some of the highlights from the conversation here.

  11. A common-sense climate index: is climate changing noticeably?

    Science.gov (United States)

    Hansen, J.; Sato, M.; Glascoe, J.; Ruedy, R.

    1998-01-01

    We propose an index of climate change based on practical climate indicators such as heating degree days and the frequency of intense precipitation. We find that in most regions the index is positive, the sense predicted to accompany global warming. In a few regions, especially in Asia and western North America, the index indicates that climate change should be apparent already, but in most places climate trends are too small to stand out above year-to-year variability. The climate index is strongly correlated with global surface temperature, which has increased as rapidly as projected by climate models in the 1980s. We argue that the global area with obvious climate change will increase notably in the next few years. But we show that the growth rate of greenhouse gas climate forcing has declined in recent years, and thus there is an opportunity to keep climate change in the 21st century less than "business-as-usual" scenarios.

  12. Climate change and the Delta

    Science.gov (United States)

    Dettinger, Michael; Anderson, Jamie; Anderson, Michael L.; Brown, Larry R.; Cayan, Daniel; Maurer, Edwin P.

    2016-01-01

    Anthropogenic climate change amounts to a rapidly approaching, “new” stressor in the Sacramento–San Joaquin Delta system. In response to California’s extreme natural hydroclimatic variability, complex water-management systems have been developed, even as the Delta’s natural ecosystems have been largely devastated. Climate change is projected to challenge these management and ecological systems in different ways that are characterized by different levels of uncertainty. For example, there is high certainty that climate will warm by about 2°C more (than late-20th-century averages) by mid-century and about 4°C by end of century, if greenhouse-gas emissions continue their current rates of acceleration. Future precipitation changes are much less certain, with as many climate models projecting wetter conditions as drier. However, the same projections agree that precipitation will be more intense when storms do arrive, even as more dry days will separate storms. Warmer temperatures will likely enhance evaporative demands and raise water temperatures. Consequently, climate change is projected to yield both more extreme flood risks and greater drought risks. Sea level rise (SLR) during the 20th century was about 22cm, and is projected to increase by at least 3-fold this century. SLR together with land subsidence threatens the Delta with greater vulnerabilities to inundation and salinity intrusion. Effects on the Delta ecosystem that are traceable to warming include SLR, reduced snowpack, earlier snowmelt and larger storm-driven streamflows, warmer and longer summers, warmer summer water temperatures, and water-quality changes. These changes and their uncertainties will challenge the operations of water projects and uses throughout the Delta’s watershed and delivery areas. Although the effects of climate change on Delta ecosystems may be profound, the end results are difficult to predict, except that native species will fare worse than invaders. Successful

  13. Abrupt Change in North American Plate Motion: Magnetostratigraphy and Paleopoles of the Early Jurassic Moenave Formation

    Science.gov (United States)

    Hutny, M. K.; Steiner, M. B.

    2001-12-01

    The J-1 cusp marks a dramatic ~ 180° change in the apparent motion of the magnetic pole with respect to North America. The cusp is defined by a sequence of poles: Chinle - Moenave - Kayenta. The Moenave pole (Ekstrand and Butler, 1989), which forms the point of the cusp, was obtained primarily from the lower member (Dinosaur Canyon) of the three-member Moenave Formation. We present new paleomagnetic data from the upper two members (Whitmore Point and Springdale Sandstone) of the formation. The Vermillion Cliffs in southern Utah present excellent exposures of the Moenave Formation. At this location, the Moenave rests uncomformably on the Late Triassic Chinle Group, although to the southeast it overlies it in a conformable manner. The Moenave is seemingly conformably overlain by the Kayenta Formation. Our study identified six polarity intervals in 100 meters of section. A preliminary paleopole from the Whitmore Point Member falls within the 95% confidence limits of the Dinosaur Canyon pole (Ekstrand and Butler, 1989), as does our pole from the top Springdale Sandstone member. If the apparent polar wander does indeed represent motion of the North American continent, then the reversal in direction implied by the J-1 cusp takes place after the deposition of the Springdale Sandstone, and either before or during the deposition of the lower Kayenta Formation. No directions intermediate between the Moenave and Kayenta directions were observed up through the uppermost Moenave strata. Within the Moenave, the lack of discernable change in magnetic direction between the three members suggests continuous deposition. This result is consistent with the observed mutually interfingering nature of the Whitmore Point and Springdale Sandstone. The sudden change in magnetic direction between the top of the Moenave and the Kayenta suggests the possibility of an unconformity between the two formations, and/or rapid continental motion following the turnaround.

  14. Precipitation extremes under climate change

    CERN Document Server

    O'Gorman, Paul A

    2015-01-01

    The response of precipitation extremes to climate change is considered using results from theory, modeling, and observations, with a focus on the physical factors that control the response. Observations and simulations with climate models show that precipitation extremes intensify in response to a warming climate. However, the sensitivity of precipitation extremes to warming remains uncertain when convection is important, and it may be higher in the tropics than the extratropics. Several physical contributions govern the response of precipitation extremes. The thermodynamic contribution is robust and well understood, but theoretical understanding of the microphysical and dynamical contributions is still being developed. Orographic precipitation extremes and snowfall extremes respond differently from other precipitation extremes and require particular attention. Outstanding research challenges include the influence of mesoscale convective organization, the dependence on the duration considered, and the need to...

  15. Improving leadership on climate change

    Energy Technology Data Exchange (ETDEWEB)

    Chandani, Achala

    2011-03-15

    The upcoming UN conference on climate change in Durban, South Africa throws a spotlight on African climate policy. As part of a knowledge-sharing initiative in Southern Africa, we assessed parliamentarians' needs for more information on climate threats and responses, and ways to improve their capabilities as key stakeholders influencing national and global decisionmaking. Funded by the UK Foreign and Commonwealth Office and partnered with the Association of European Parliamentarians with Africa (AWEPA), IIED worked with parliamentarians in the Southern Africa Customs Union (SACU) — Botswana, Lesotho, Namibia, South Africa and Swaziland — through interviews, literature surveys, field trips and workshops. Similar studies in Malawi and Scotland also fed into this project.

  16. Learned vocal variation is associated with abrupt cryptic genetic change in a parrot species complex.

    Directory of Open Access Journals (Sweden)

    Raoul F H Ribot

    Full Text Available Contact zones between subspecies or closely related species offer valuable insights into speciation processes. A typical feature of such zones is the presence of clinal variation in multiple traits. The nature of these traits and the concordance among clines are expected to influence whether and how quickly speciation will proceed. Learned signals, such as vocalizations in species having vocal learning (e.g. humans, many birds, bats and cetaceans, can exhibit rapid change and may accelerate reproductive isolation between populations. Therefore, particularly strong concordance among clines in learned signals and population genetic structure may be expected, even among continuous populations in the early stages of speciation. However, empirical evidence for this pattern is often limited because differences in vocalisations between populations are driven by habitat differences or have evolved in allopatry. We tested for this pattern in a unique system where we may be able to separate effects of habitat and evolutionary history. We studied geographic variation in the vocalizations of the crimson rosella (Platycercus elegans parrot species complex. Parrots are well known for their life-long vocal learning and cognitive abilities. We analysed contact calls across a ca 1300 km transect encompassing populations that differed in neutral genetic markers and plumage colour. We found steep clinal changes in two acoustic variables (fundamental frequency and peak frequency position. The positions of the two clines in vocal traits were concordant with a steep cline in microsatellite-based genetic variation, but were discordant with the steep clines in mtDNA, plumage and habitat. Our study provides new evidence that vocal variation, in a species with vocal learning, can coincide with areas of restricted gene flow across geographically continuous populations. Our results suggest that traits that evolve culturally can be strongly associated with reduced gene flow

  17. Synchronous climate changes in Antarctica and the North Atlantic

    Science.gov (United States)

    Steig, E.J.; Brook, E.J.; White, J.W.C.; Sucher, C.M.; Bender, M.L.; Lehman, S.J.; Morse, D.L.; Waddington, E.D.; Clow, G.D.

    1998-01-01

    Central Greenland ice cores provide evidence of abrupt changes in climate over the past 100,000 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic, confirming the link between millennial-scale climate variability and ocean thermohaline circulation. It is shown here that two of the most prominent North Atlantic events - the rapid warming that makes the end of the last glacial period and the Bolling/Allerod-Younger Dryas oscillation - are also recorded in an ice core from Taylor Dome, in the western Ross Sea sector of Antarctica. This result contrasts with evidence from ice cores in other regions of Antarctica, which show an asynchronous response between the Northern and Southern Hemispheres.

  18. Some Physical Consequences of Abrupt Changes in the Multipole Moments of a Gravitating Body

    CERN Document Server

    Barrabès, C; Hogan, P A

    1997-01-01

    The Barrabès-Israel theory of light-like shells in General Relativity= is used to show explicitly that in general a light-like shell is accompanied= by an impulsive gravitational wave. The gravitational wave is identified by = its Petrov Type N contribution to a Dirac delta-function term in the Weyl conformal curvature tensor (with the delta-function singular on the null hypersurface history of the wave and shell). An example is described in w= hich an asymptotically flat static vacuum Weyl space-time experiences a sudden change across a null hypersurface in the multipole moments of its isolate= d axially symmetric source. A light-like shell and an impulsive gravitation= al wave are identified, both having the null hypersurface as history. The stress-energy in the shell is dominated (at large distance from the sourc= e) by the jump in the monopole moment (the mass) of the source with the jump in= the quadrupole moment mainly responsible for the stress being anisotropic. Th= e gravitational wave owes its exis...

  19. Climate Change and Civil Violence

    Science.gov (United States)

    van der Vink, G.; Plancherel, Y.; Hennet, C.; Jones, K. D.; Abdullah, A.; Bradshaw, J.; Dee, S.; Deprez, A.; Pasenello, M.; Plaza-Jennings, E.; Roseman, D.; Sopher, P.; Sung, E.

    2009-05-01

    The manifestations of climate change can result in humanitarian impacts that reverse progress in poverty- reduction, create shortages of food and resources, lead to migration, and ultimately result in civil violence and conflict. Within the continent of Africa, we have found that environmentally-related variables are either the cause or the confounding factor for over 80% of the civil violence events during the last 10 years. Using predictive climate models and land-use data, we are able to identify populations in Africa that are likely to experience the most severe climate-related shocks. Through geospatial analysis, we are able to overlay these areas of high risk with assessments of both the local population's resiliency and the region's capacity to respond to climate shocks should they occur. The net result of the analysis is the identification of locations that are becoming particularly vulnerable to future civil violence events (vulnerability hotspots) as a result of the manifestations of climate change. For each population group, over 600 social, economic, political, and environmental indicators are integrated statistically to measures the vulnerability of African populations to environmental change. The indicator time-series are filtered for data availability and redundancy, broadly ordered into four categories (social, political, economic and environmental), standardized and normalized. Within each category, the dominant modes of variability are isolated by principal component analysis and the loadings of each component for each variable are used to devise composite index scores. Comparisons of past vulnerability with known environmentally-related conflicts demonstrates the role that such vulnerability hotspot maps can play in evaluating both the potential for, and the significance of, environmentally-related civil violence events. Furthermore, the analysis reveals the major variables that are responsible for the population's vulnerability and therefore

  20. Climate project screening tool: an aid for climate change adaptation

    Science.gov (United States)

    Toni Lyn Morelli; Sharon Yeh; Nikola M. Smith; Mary Beth Hennessy; Constance I. Millar

    2012-01-01

    To address the impacts of climate change, land managers need techniques for incorporating adaptation into ongoing or impending projects. We present a new tool, the Climate Project Screening Tool (CPST), for integrating climate change considerations into project planning as well as for developing concrete adaptation options for land managers. We designed CPST as part of...

  1. Asia's changing role in global climate change.

    Science.gov (United States)

    Siddiqi, Toufiq A

    2008-10-01

    Asia's role in global climate change has evolved significantly from the time when the Kyoto Protocol was being negotiated. Emissions of carbon dioxide, the principal greenhouse gas, from energy use in Asian countries now exceed those from the European Union or North America. Three of the top five emitters-China, India, and Japan, are Asian countries. Any meaningful global effort to address global climate change requires the active cooperation of these and other large Asian countries, if it is to succeed. Issues of equity between countries, within countries, and between generations, need to be tackled. Some quantitative current and historic data to illustrate the difficulties involved are provided, and one approach to making progress is suggested.

  2. Abrupt climate variability since the last deglaciation based on a high-resolution, multi-proxy peat record from NW Iran: The hand that rocked the Cradle of Civilization?

    Science.gov (United States)

    Sharifi, Arash; Pourmand, Ali; Canuel, Elizabeth A.; Ferer-Tyler, Erin; Peterson, Larry C.; Aichner, Bernhard; Feakins, Sarah J.; Daryaee, Touraj; Djamali, Morteza; Beni, Abdolmajid Naderi; Lahijani, Hamid A. K.; Swart, Peter K.

    2015-09-01

    We present a high-resolution (sub-decadal to centennial), multi-proxy reconstruction of aeolian input and changes in palaeohydrological conditions based on a 13000 Yr record from Neor Lake's peripheral peat in NW Iran. Variations in relative abundances of refractory (Al, Zr, Ti, and Si), redox sensitive (Fe) and mobile (K and Rb) elements, total organic carbon (TOC), δ13CTOC, compound-specific leaf wax hydrogen isotopes (δD), carbon accumulation rates and dust fluxes presented here fill a large gap in the existing terrestrial paleoclimate records from the interior of West Asia. Our results suggest that a transition occurred from dry and dusty conditions during the Younger Dryas (YD) to a relatively wetter period with higher carbon accumulation rates and low aeolian input during the early Holocene (9000-6000 Yr BP). This period was followed by relatively drier and dustier conditions during middle to late Holocene, which is consistent with orbital changes in insolation that affected much of the northern hemisphere. Numerous episodes of high aeolian input spanning a few decades to millennia are prevalent during the middle to late Holocene. Wavelet analysis of variations in Ti abundances as a proxy for aeolian input revealed notable periodicities at 230, 320, and 470 years with significant periodicities centered around 820, 1550, and 3110 years over the last 13000 years. Comparison with palaeoclimate archives from West Asia, the North Atlantic and African lakes point to a teleconnection between North Atlantic climate and the interior of West Asia during the last glacial termination and the Holocene epoch. We further assess the potential role of abrupt climate change on early human societies by comparing our record of palaeoclimate variability with historical, geological and archaeological archives from this region. The terrestrial record from this study confirms previous evidence from marine sediments of the Arabian Sea that suggested climate change influenced the

  3. Climate change mitigation in China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Bo

    2012-07-01

    China has been experiencing great economic development and fast urbanisation since its reforms and opening-up policy in 1978. However, these changes are reliant on consumption of primary energy, especially coal, characterised by high pollution and low efficiency. China's greenhouse gas (GHG) emissions, with carbon dioxide (CO{sub 2}) being the most significant contributor, have also been increasing rapidly in the past three decades. Responding to both domestic challenges and international pressure regarding energy, climate change and environment, the Chinese government has made a point of addressing climate change since the early 2000s. This thesis provides a comprehensive analysis of China's CO{sub 2} emissions and policy instruments for mitigating climate change. In the analysis, China's CO{sub 2} emissions in recent decades were reviewed and the Environmental Kuznets Curve (EKC) hypothesis examined. Using the mostly frequently studied macroeconomic factors and time-series data for the period of 1980-2008, the existence of an EKC relationship between CO{sub 2} per capita and GDP per capita was verified. However, China's CO{sub 2} emissions will continue to grow over coming decades and the turning point in overall CO{sub 2} emissions will appear in 2078 according to a crude projection. More importantly, CO{sub 2} emissions will not spontaneously decrease if China continues to develop its economy without mitigating climate change. On the other hand, CO{sub 2} emissions could start to decrease if substantial efforts are made. China's present mitigation target, i.e. to reduce CO{sub 2} emissions per unit of GDP by 40-45 % by 2020 compared with the 2005 level, was then evaluated. Three business-as-usual (BAU) scenarios were developed and compared with the level of emissions according to the mitigation target. The calculations indicated that decreasing the CO{sub 2} intensity of GDP by 40-45 % by 2020 is a challenging but hopeful target. To

  4. Analysis of streamflow variations in the Heihe River Basin, northwest China: Trends, abrupt changes, driving factors and ecological influences

    Directory of Open Access Journals (Sweden)

    Aijing Zhang

    2015-03-01

    New Hydrological Insights for the Region: The findings of this study indicated that although the streamflow coming from the upper reaches have risen, those flowing to the lower reaches have declined significantly. Analysis of the correlation between climatic factors and streamflow variations and the assessment of the development of socioeconomics revealed that: (1 rising temperature and precipitation are the main cause to explain the increases in streamflow in the upper HRB; and (2 human activities in the middle reaches of the HRB rather than climate changes were primarily responsible for the water shortage and ecological deterioration of the lower HRB.

  5. Lack of Climate Expertise Among Climate Change Educators

    Science.gov (United States)

    Doesken, N.

    2015-12-01

    It is hard to know enough about anything. Many educators fully accept the science as well as the hype associated with climate change and try very hard to be climate literate. But many of these same educators striving for greater climate literacy are surprisingly ignorant about the climate itself (typical seasonal cycles, variations, extremes, spatial patterns and the drivers that produce them). As a result, some of these educators and their students are tempted to interpret each and every hot or cold and wet or dry spell as convincing evidence of climate change even as climate change "skeptics" view those same fluctuations as normal. Educators' overreaction risks a backfire reaction resulting in loss of credibility among the very groups they are striving to educate and influence. This presentation will include reflections on climate change education and impacts based on 4 decades of climate communication in Colorado.

  6. Handbook of Climate Change Mitigation

    CERN Document Server

    Seiner, John; Suzuki, Toshio; Lackner, Maximilian

    2012-01-01

    There is a mounting consensus that human behavior is changing the global climate and its consequence could be catastrophic. Reducing the 24 billion metric tons of carbon dioxide emissions from stationary and mobile sources is a gigantic task involving both technological challenges and monumental financial and societal costs. The pursuit of sustainable energy resources, environment, and economy has become a complex issue of global scale that affects the daily life of every citizen of the world. The present mitigation activities range from energy conservation, carbon-neutral energy conversions, carbon advanced combustion process that produce no greenhouse gases and that enable carbon capture and sequestion, to other advanced technologies. From its causes and impacts to its solutions, the issues surrounding climate change involve multidisciplinary science and technology. This handbook will provide a single source of this information. The book will be divided into the following sections: Scientific Evidence of Cl...

  7. Challenges and Possibilities in Climate Change Education

    Science.gov (United States)

    Pruneau,, Diane; Khattabi, Abdellatif; Demers, Melanie

    2010-01-01

    Educating and communicating about climate change is challenging. Researchers reported that climate change concepts are often misunderstood. Some people do not believe that climate change will have impacts on their own life. Other challenges may include people's difficulty in perceiving small or gradual environmental changes, the fact that…

  8. Complexity in Climate Change Manipulation Experiments

    DEFF Research Database (Denmark)

    Kreyling, Juergen; Beier, Claus

    2014-01-01

    Climate change goes beyond gradual changes in mean conditions. It involves increased variability in climatic drivers and increased frequency and intensity of extreme events. Climate manipulation experiments are one major tool to explore the ecological impacts of climate change. Until now, precipi...... variability in temperature are ecologically important. Embracing complexity in future climate change experiments in general is therefore crucial.......Climate change goes beyond gradual changes in mean conditions. It involves increased variability in climatic drivers and increased frequency and intensity of extreme events. Climate manipulation experiments are one major tool to explore the ecological impacts of climate change. Until now......, precipitation experiments have dealt with temporal variability or extreme events, such as drought, resulting in a multitude of approaches and scenarios with limited comparability among studies. Temperature manipulations have mainly been focused only on warming, resulting in better comparability among studies...

  9. Teaching Climate Change Through Music

    Science.gov (United States)

    Weiss, P. S.

    2007-12-01

    During 2006, Peter Weiss aka "The Singing Scientist" performed many music assemblies for elementary schools (K-5) in Santa Cruz County, California, USA. These assemblies were an opportunity for him to mix a discussion of climate change with rock n' roll. In one song called "Greenhouse Glasses", Peter and his band the "Earth Rangers" wear over-sized clown glasses with "molecules" hanging off them (made with Styrofoam balls and pipe cleaners). Each molecule is the real molecular structure of a greenhouse gas, and the song explains how when the wearer of these glasses looks up in the sky, he/she can see the "greenhouse gases floating by." "I've seen more of them this year than the last / 'Cuz fossil fuels are burning fast / I wish everyone could see through these frames / Then maybe we could prevent climate change" Students sing, dance and get a visual picture of something that is invisible, yet is part of a very real problem. This performance description is used as an example of an educational style that can reach a wide audience and provide a framework for the audience as learners to assimilate future information on climate change. The hypothesis is that complex socio-environmental issues like climate change that must be taught in order to achieve sustainability are best done so through alternative mediums like music. Students develop awareness which leads to knowledge about chemistry, physics, and biology. These kinds of experiences which connect science learning to fun activities and community building are seriously lacking in primary and secondary schools and are a big reason why science illiteracy is a current social problem. Science education is also paired with community awareness (including the local plant/animal community) and cooperation. The Singing Scientist attempts to create a culture where it is cool to care about the environment. Students end up gardening in school gardens together and think about their "ecological footprint".

  10. Nonlinearly combined impacts of initial perturbation from human activities and parameter perturbation from climate change on the grassland ecosystem

    Directory of Open Access Journals (Sweden)

    G. Sun

    2011-11-01

    Full Text Available Human activities and climate change are important factors that affect grassland ecosystems. A new optimization approach, the approach of conditional nonlinear optimal perturbation (CNOP related to initial and parameter perturbations, is employed to explore the nonlinearly combined impacts of human activities and climate change on a grassland ecosystem using a theoretical grassland model. In our study, it is assumed that the initial perturbations and parameter perturbations are regarded as human activities and climate change, respectively. Numerical results indicate that the climate changes causing the maximum effect in the grassland ecosystem are different under disparate intensities of human activities. This implies the pattern of climate change is very critical to the maintenance or degradation of grassland ecosystem in light of high intensity of human activities and that the grassland ecosystem should be rationally managed when the moisture index decreases. The grassland ecosystem influenced by the nonlinear combination of human activities and climate change undergoes abrupt change, while the grassland ecosystem affected by other types of human activities and climate change fails to show the abrupt change under a certain range of perturbations with the theoretical model. The further numerical analyses also indicate that the growth of living biomass and the evaporation from soil surface shaded by the wilted biomass may be crucial factors contributing to the abrupt change of the grassland equilibrium state within the theoretical model.

  11. NASA Nice Climate Change Education

    Science.gov (United States)

    Frink, K.; Crocker, S.; Jones, W., III; Marshall, S. S.; Anuradha, D.; Stewart-Gurley, K.; Howard, E. M.; Hill, E.; Merriweather, E.

    2013-12-01

    Authors: 1 Kaiem Frink, 4 Sherry Crocker, 5 Willie Jones, III, 7 Sophia S.L. Marshall, 6 Anuadha Dujari 3 Ervin Howard 1 Kalota Stewart-Gurley 8 Edwinta Merriweathe Affiliation: 1. Mathematics & Computer Science, Virginia Union University, Richmond, VA, United States. 2. Mathematics & Computer Science, Elizabeth City State Univ, Elizabeth City, NC, United States. 3. Education, Elizabeth City State University, Elizabeth City, NC, United States. 4. College of Education, Fort Valley State University , Fort Valley, GA, United States. 5. Education, Tougaloo College, Jackson, MS, United States. 6. Mathematics, Delaware State University, Dover, DE, United States. 7. Education, Jackson State University, Jackson, MS, United States. 8. Education, Alabama Agricultural and Mechanical University, Huntsville, AL, United States. ABSTRACT: In this research initiative, the 2013-2014 NASA NICE workshop participants will present best educational practices for incorporating climate change pedagogy. The presentation will identify strategies to enhance instruction of pre-service teachers to aligned with K-12 Science, Technology, Engineering and Mathematics (STEM) standards. The presentation of best practices should serve as a direct indicator to address pedagogical needs to include climate education within a K-12 curriculum Some of the strategies will include inquiry, direct instructions, and cooperative learning . At this particular workshop, we have learned about global climate change in regards to how this is going to impact our life. Participants have been charged to increase the scientific understanding of pre-service teachers education programs nationally to incorporate climate education lessons. These recommended practices will provide feasible instructional strategies that can be easily implemented and used to clarify possible misconceptions and ambiguities in scientific knowledge. Additionally, the presentation will promote an awareness to the many facets in which climate

  12. Climate change mitigation in Africa

    Energy Technology Data Exchange (ETDEWEB)

    Mackenzie, G.A.; Turkson, J.K.; Davidson, O.R. [eds.

    1998-10-01

    The UNEP Collaborating Centre on Energy and Environment (UCCEE) in conjunction with the Southern Centre for Energy and Environment (SCEE) hosted a conference on `Climate Change Mitigation in Africa` between 18 and 20 May. The Conference set out to address the following main objectives: to present to a wider audience the results of UNEP/GEF and related country studies; to present results of regional mitigation analysis; exchange of information with similar projects in the region; to expose countries to conceptual and methodological issues related to climate change mitigation; to provide input to national development using climate change related objectives. This volume contains reports of the presentations and discussions, which took place at the conference at Victoria Falls between 18 and 20 May 1998. Representatives of 11 country teams made presentations and in addition two sub-regions were discussed: the Maghreb region and SADC. The conference was attended by a total of 63 people, representing 22 African countries as well as international organisations. (EG)

  13. Climate Change: a Theoretical Review

    Directory of Open Access Journals (Sweden)

    Muhammad Ishaq-ur Rahman

    2013-01-01

    Full Text Available Climate Change has been undoubtedly the most illustrious environmental issue since late 20th century. But neither the discourse merely emerged during that time, nor it was problematized in the same way since its onset. History of Climate Change discourse reveals that from a purely scientific concern it has turned into a public agenda that is nowadays more inclined to be development problem. Transformations have brought about a complete new paradigm every time. This article presents a theoretical analysis of the Climate Change discourse and to do so it captured the underlying philosophy of the issue using Thomas Kuhn’s well-known thesis of ‘paradigm shift’. In particular it discusses about the crisis that lead the issue towards transformations; explores key perspectives around the crisis thus representation of the issue in the environmental discourse over the time. While this paper establishes that with the beginning of the 21st century, the discourse entered into a new paradigm and will reach to a critical point by the end of 2012, it finally postulates some measures that the discourse might integrate with the existing to advance beyond that point.

  14. Past and Current Climate Change

    Science.gov (United States)

    Mercedes Rodríguez Ruibal, Ma

    2014-05-01

    In 1837 the Swiss geologist and palaeontologist Louis Agassiz was the first scientist to propose the existence of an ice age in the Earth's past. Nearly two centuries after discussing global glacial periods... while the average global temperature is rising very quickly because of our economic and industrial model. In tribute to these pioneers, we have selected a major climate change of the past as the Snowball Earth and, through various activities in the classroom, compared to the current anthropogenic climate change. First, we include multiple geological processes that led to a global glaciation 750 million years ago as the decrease in the atmospheric concentration of greenhouse gases such as CO2 and CH4, the effect of climate variations in solar radiation due to emissions of volcanic dust and orbital changes (Milankovitch cycles), being an essential part of this model the feedback mechanism of the albedo of the ice on a geological scale. Moreover, from simple experiments and studies in the classroom this time we can compare the past with the current anthropogenic global warming we are experiencing and some of its consequences, highlighting that affect sea level rise, increased extreme and effects on health and the biosphere weather.

  15. Exploring the Multifaceted Topic of Climate Change in Our Changing Climate and Living With Our Changing Climate

    Science.gov (United States)

    Brey, J. A.; Kauffman, C.; Geer, I. W.; Mills, E. W.; Nugnes, K. A.; Stimach, A. E.

    2015-12-01

    As the effects of climate change become more profound, climate literacy becomes increasingly important. The American Meteorological Society (AMS) responds to this need through the publication of Our Changing Climate and Living With Our Changing Climate. Both publications incorporate the latest scientific understandings of Earth's climate system from reports such as IPCC AR5 and the USGCRP's Third National Climate Assessment. Topic In Depth sections appear throughout each chapter and lead to more extensive, multidisciplinary information related to various topics. Additionally, each chapter closes with a For Further Exploration essay, which addresses specific topics that complement a chapter concept. Web Resources, which encourage additional exploration of chapter content, and Scientific Literature, from which chapter content was derived can also be found at the conclusion of each chapter. Our Changing Climate covers a breadth of topics, including the scientific principles that govern Earth's climate system and basic statistics and geospatial tools used to investigate the system. Released in fall 2015, Living With Our Changing Climate takes a more narrow approach and investigates human and ecosystem vulnerabilities to climate change, the role of energy choices in affecting climate, actions humans can take through adaption, mitigation, and policy to lessen vulnerabilities, and psychological and financial reasons behind climate change denial. While Living With Our Changing Climate is intended for programs looking to add a climate element into their curriculum, Our Changing Climate is part of the AMS Climate Studies course. In a 2015 survey of California University of Pennsylvania undergraduate students using Our Changing Climate, 82% found it comfortable to read and utilized its interactive components and resources. Both ebooks illuminate the multidisciplinary aspect of climate change, providing the opportunity for a more sustainable future.

  16. Monitoring channel head erosion processes in response to an artificially induced abrupt base level change using time-lapse photography 2301

    Science.gov (United States)

    Headcut and channel extension in response to an abrupt base level change in 2004 of approximately 1m was studied in a 1.29 ha semiarid headwater drainage on the Walnut Gulch Experimental Watershed (WGEW) in southeastern Arizona, USA. Field observations and time-lapse photography were coupled with hy...

  17. Managing Climate Change Refugia for Biodiversity Conservation

    Science.gov (United States)

    Climate change threatens to create fundamental shifts in in the distributions and abundances of species. Given projected losses, increased emphasis on management for ecosystem resilience to help buffer fish and wildlife populations against climate change is emerging. Such effort...

  18. Managing Climate Change Refugia for Biodiversity Conservation

    Science.gov (United States)

    Climate change threatens to create fundamental shifts in in the distributions and abundances of species. Given projected losses, increased emphasis on management for ecosystem resilience to help buffer fish and wildlife populations against climate change is emerging. Such effort...

  19. Wildlife conservation in a changing climate

    National Research Council Canada - National Science Library

    Doak, Daniel F; Brodie, Jedediah F; Post, Eric S

    2012-01-01

    Bringing together leaders in the fields of climate change ecology, wildlife population dynamics, and environmental policy, this title examines the impacts of climate change on populations of terrestrial vertebrates...

  20. Climate Change, Indoor Environment and Health

    Science.gov (United States)

    Climate change is becoming a driving force for improving energy efficiency because saving energy can help reduce the greenhouse gas emissions that contribute to climate change. However, it is important to balance energy saving measures with ventilation...

  1. Climate change and the Great Basin

    Science.gov (United States)

    Jeanne C. Chambers

    2008-01-01

    Climate change is expected to have significant impacts on the Great Basin by the mid-21st century. The following provides an overview of past and projected climate change for the globe and for the region.

  2. Protecting Your Forest from Climate Change

    Science.gov (United States)

    Steven McNulty

    2009-01-01

    Climate change is already impacting our forests and the situation is ongoing. As a landowner, there are management tools that you can use to help reduce the likelihood that climate change will cause serious harm to your forest.

  3. farmers' perception and adaptation to climate change

    African Journals Online (AJOL)

    USER

    2014-11-17

    Nov 17, 2014 ... Similarly, farmers perception of climate change was affected significantly by ... Key Words: Climate Change, East Wollega, Western Ethiopia. Introduction ..... participated on planting trees in reducing the problem caused by ...

  4. Climate variability and vulnerability to climate change: a review.

    Science.gov (United States)

    Thornton, Philip K; Ericksen, Polly J; Herrero, Mario; Challinor, Andrew J

    2014-11-01

    The focus of the great majority of climate change impact studies is on changes in mean climate. In terms of climate model output, these changes are more robust than changes in climate variability. By concentrating on changes in climate means, the full impacts of climate change on biological and human systems are probably being seriously underestimated. Here, we briefly review the possible impacts of changes in climate variability and the frequency of extreme events on biological and food systems, with a focus on the developing world. We present new analysis that tentatively links increases in climate variability with increasing food insecurity in the future. We consider the ways in which people deal with climate variability and extremes and how they may adapt in the future. Key knowledge and data gaps are highlighted. These include the timing and interactions of different climatic stresses on plant growth and development, particularly at higher temperatures, and the impacts on crops, livestock and farming systems of changes in climate variability and extreme events on pest-weed-disease complexes. We highlight the need to reframe research questions in such a way that they can provide decision makers throughout the food system with actionable answers, and the need for investment in climate and environmental monitoring. Improved understanding of the full range of impacts of climate change on biological and food systems is a critical step in being able to address effectively the effects of climate variability and extreme events on human vulnerability and food security, particularly in agriculturally based developing countries facing the challenge of having to feed rapidly growing populations in the coming decades. © 2014 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

  5. The science of climate change.

    Energy Technology Data Exchange (ETDEWEB)

    Doctor, R. D.

    1999-09-10

    A complex debate is underway on climate change linked to proposals for costly measures that would reshape our power grid. This confronts technical experts outside of the geophysical disciplines with extensive, but unfamiliar, data both supporting and refuting claims that serious action is warranted. For example, evidence is brought to the table from one group of astrophysicists concerned with sunspots--this group believes there is no issue man can manage; while another group of oceanographers concerned with the heat balance in the world's oceans are very alarmed at the loss of arctic ice. What is the evidence? In an effort to put some of these issues in perspective for a technical audience, without a background in geophysics, a brief survey will consider (1) an overview of the 300 years of scientific inquiry on man's relationship to climate; (2) a basic discussion of what is meant by the ''greenhouse'' and why there are concerns which include not only CO{sub 2}, but also CH{sub 4}, N{sub 2}O, and CFC's; (3) the geological record on CO{sub 2}--which likely was present at 1,000 times current levels when life began; (4) the solar luminosity and sunspot question; and (5) the current evidence for global climate change. We are at a juncture where we are attempting to understand the earth as an integrated dynamic system, rather than a collection of isolated components.

  6. Forest Policies Addressing Climate Change in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    As a developing country with a large population and a fragile ecological environment, China is particularly vulnerable to the adverse effects of climate change. Beginning with the Rio Conference of 1992 China has played a progressively enhanced role in combating climate change. A series of policies and measures to address climate change have been taken in the overall context of national sustainable development strategy, making positive contributions to the mitigation and adaptation to climate change, among ...

  7. Climate variability and vulnerability to climate change: a review

    Science.gov (United States)

    Thornton, Philip K; Ericksen, Polly J; Herrero, Mario; Challinor, Andrew J

    2014-01-01

    The focus of the great majority of climate change impact studies is on changes in mean climate. In terms of climate model output, these changes are more robust than changes in climate variability. By concentrating on changes in climate means, the full impacts of climate change on biological and human systems are probably being seriously underestimated. Here, we briefly review the possible impacts of changes in climate variability and the frequency of extreme events on biological and food systems, with a focus on the developing world. We present new analysis that tentatively links increases in climate variability with increasing food insecurity in the future. We consider the ways in which people deal with climate variability and extremes and how they may adapt in the future. Key knowledge and data gaps are highlighted. These include the timing and interactions of different climatic stresses on plant growth and development, particularly at higher temperatures, and the impacts on crops, livestock and farming systems of changes in climate variability and extreme events on pest-weed-disease complexes. We highlight the need to reframe research questions in such a way that they can provide decision makers throughout the food system with actionable answers, and the need for investment in climate and environmental monitoring. Improved understanding of the full range of impacts of climate change on biological and food systems is a critical step in being able to address effectively the effects of climate variability and extreme events on human vulnerability and food security, particularly in agriculturally based developing countries facing the challenge of having to feed rapidly growing populations in the coming decades. PMID:24668802

  8. Conceptualizing Climate Change in the Context of a Climate System: Implications for Climate and Environmental Education

    Science.gov (United States)

    Shepardson, Daniel P.; Niyogi, Dev; Roychoudhury, Anita; Hirsch, Andrew

    2012-01-01

    Today there is much interest in teaching secondary students about climate change. Much of this effort has focused directly on students' understanding of climate change. We hypothesize, however, that in order for students to understand climate change they must first understand climate as a system and how changes to this system due to both natural…

  9. What climate changes do 400 ppm commit us to? (Invited)

    Science.gov (United States)

    Zickfeld, K.

    2013-12-01

    Atmospheric CO2 is approaching an annual average concentration of 400 ppm. This paper explores the long-term climate changes that this level of atmospheric CO2 commits us to. Climate change commitment refers to the climate changes that are to be expected in the future in response to past human activities. Several types of climate change commitment have been discussed in the literature. This paper investigates the long-term climate response to the current atmospheric composition perpetuated over several centuries (constant composition commitment) and the response to an abrupt cessation of greenhouse gas emissions (zero emission commitment) using an Earth System Model of Intermediate Complexity (EMIC). The committed changes in both the physical and biogeochemical Earth system components are quantified, and the uncertainties in the magnitude and the time scales of the simulated changes are explored using sensitivity analysis and results from an EMIC intercomparison undertaken in support of the Fifth Assessment Report (AR5) of the IPCC. A second research question addresses whether it is feasible to return from 400 ppm to lower levels of atmospheric CO2 on human timescales using 'negative emissions' (i.e. net removal of atmospheric CO2 from the atmosphere). The implementation of negative emission technology (e.g. biomass energy with carbon capture and geological storage) may be desirable if the committed climate changes of 400 ppm exceed 'safe' levels. The feasibility of returning to lower CO2 levels is assessed based on the response of the Earth System and currently known limits of negative emission technology.

  10. Climate changes since the mid-Holocene in the Middle Atlas, Morocco

    Directory of Open Access Journals (Sweden)

    M. Nourelbait

    2015-09-01

    Full Text Available The Holocene climate is known to be rather stable although with few abrupt changes that lasted few decades. The present study is related the climate changes and their environmental impacts during the last 6000 years from a fossil record collected in the Middle Atlas, Morocco. Reconstruction of three climate variables (January temperature (Tjan, annual precipitation (Pann and a precipitation seasonal index (SI was based on pollen data and analyzed various bio and geo-chemical elements. Then we evaluated the relationships between all the environmental variables. Climate over the last 6000 years was rather stable with a smooth trend of aridity towards the present. Tjan has varied within about 2 °C range and Pann within less than 100 mm yr−1. Despite such overall climate stability, after ca. 3750 cal BP some important changes were observe in the ecosystem composition, the carbon isotopic contents of organic matter in lake sediments (δ13C, the total organic carbon and nitrogen amount and the carbon to nitrogen ratio (C / N. These environmental changes are related to the transition in the conifer forest between the Atlas cedar, which expanded after 3750 cal BP, and the pine forest. These vegetation changes have impacted the sedimentation type and composition into the lake. Between 5500 and 5000 cal BP an abrupt change is recorded in all bio and geo-chemical indicators as well as in the pollen data. The multi-proxy analysis, taking into account the climate variables, tends to indicate that it was mainly a decrease in temperature without a significant change in the overall amount of precipitation. In summary, the present study confirms the overall climate stability over the last 6000 years and highlights the presence of short and abrupt climate events.

  11. Climate change response framework overview: Chapter 1

    Science.gov (United States)

    Chris Swanston; Maria Janowiak; Patricia. Butler

    2012-01-01

    Managers currently face the immense challenge of anticipating the effects of climate change on forest ecosystems and then developing and applying management responses for adapting forests to future conditions. The Climate Change Response Framework (CCRF) is a highly collaborative approach to helping land managers understand the potential effects of climate change on...

  12. Climate Change Education for Mitigation and Adaptation

    Science.gov (United States)

    Anderson, Allison

    2012-01-01

    This article makes the case for the education sector an untapped opportunity to combat climate change. It sets forth a definition of Climate Change Education for Sustainable Development that is comprehensive and multidisciplinary and asserts that it must not only include relevant content knowledge on climate change, environmental and social…

  13. Climate Change Ignorance: An Unacceptable Legacy

    Science.gov (United States)

    Boon, Helen J.

    2015-01-01

    Climate change effects will be most acutely felt by future generations. Recent prior research has shown that school students' knowledge of climate change science is very limited in rural Australia. The purpose of this study was to assess the capacity of preservice teachers and parents to transmit climate change information and understanding to…

  14. Risk Communication, Moral Emotions and Climate Change.

    NARCIS (Netherlands)

    Roeser, Sabine

    2012-01-01

    This article discusses the potential role that emotions might play in enticing a lifestyle that diminishes climate change. Climate change is an important challenge for society. There is a growing consensus that climate change is due to our behavior, but few people are willing to significantly adapt

  15. Climate Change Education for Mitigation and Adaptation

    Science.gov (United States)

    Anderson, Allison

    2012-01-01

    This article makes the case for the education sector an untapped opportunity to combat climate change. It sets forth a definition of Climate Change Education for Sustainable Development that is comprehensive and multidisciplinary and asserts that it must not only include relevant content knowledge on climate change, environmental and social…

  16. Climate Change Ignorance: An Unacceptable Legacy

    Science.gov (United States)

    Boon, Helen J.

    2015-01-01

    Climate change effects will be most acutely felt by future generations. Recent prior research has shown that school students' knowledge of climate change science is very limited in rural Australia. The purpose of this study was to assess the capacity of preservice teachers and parents to transmit climate change information and understanding to…

  17. Arctic Warmth Becomes a Mid-Latitude Chill: Using Online Data To Teach Climate Change Science

    Science.gov (United States)

    Eichorn, David N.

    Climate change education is a growing sub-discipline of science education. This research reports on the use of the fundamental principles of atmospheric science to explain the potential impact of regional climate change across global latitudes. Since the Arctic is responding to climate change faster than any other place on earth, it offers us a real-time opportunity to teach the larger scale impacts of abrupt regional scale change. In this research I merged elements of both the atmospheric and climate sciences into an online course. The course uses principles of meteorology to teach climate change science and demonstrate cause and effect relationships within the atmosphere. Students learn how climate change in one part of the world impacts weather elsewhere through the use of animated and descriptive video lectures that explain basic atmospheric thermodynamics processes. This paper includes a lesson plan that shows how climatic warming in the Arctic causes colder US winter weather. Formative and summative evaluations taken from course evaluations and exams suggest using meteorology to teach climate change is an effective way to educate students in high school and undergraduate college level courses about cross latitudinal influences of climate change. Keywords: Climate Change, Global Warming, Arctic, Climate Literacy, Lesson Plan, Arctic Oscillation, Education

  18. Inter-hemispheric linkages in climate change: paleo-perspectives for future climate change

    Directory of Open Access Journals (Sweden)

    J. Shulmeister

    2006-01-01

    inter-annual signal dominant. Paleo-data demonstrate that the relative importance of the two periodicities changes through time, with longer periodicities dominant in the early Holocene. 3. The recognition of climate modulation of oscillatory systems by climate events. We examine the relationship of ENSO to a SH climate event, the Antarctic cold reversal (ACR, in the New Zealand region. We demonstrate that the onset of the ACR was associated with the apparent switching on of an ENSO signal in New Zealand. We infer that this related to enhanced zonal SW winds with the amplification of the pressure fields allowing an existing but weak ENSO signal to manifest itself. Teleconnections of this nature would be difficult to predict for future abrupt change as boundary conditions cannot readily be specified. Paleo-data are critical to predicting the teleconnections of future changes.

  19. Climatic change and river ice breakup

    Energy Technology Data Exchange (ETDEWEB)

    Beltaos, S. [Environment Canada, National Water Research Institute, Burlington, ON (Canada); Burrell, B. C. [New Brunswick Dept. of the Environment and Local Government, Sciences and Planning Division, Fredericton, NB (Canada)

    2003-07-01

    An overview of climatic factors and impact relative to river ice engineering and science is presented. An explanation of the fundamentals of climatic change is followed by a review of direct and indirect climatic influences that govern river ice breakup and related trends. Known responses of river ice to climatic change and potential future changes to ice breakup processes are described along with the probable ecological and socio-economic consequences of these changes. Changes in engineering approaches to accommodate the present ice regime and predicted changes in climatic variables that affect river ice processes and reduce the vulnerability of infrastructure and ecosystems to climatic change are examined. Future research on the links between river ice and stream ecology is suggested to identify ecological concerns that may result from changes in river ice regimes induced by climatic change. 60 refs., 3 figs.

  20. Climate change science compendium 2009

    Energy Technology Data Exchange (ETDEWEB)

    McMullen, C.P.; Jabbour, J.

    2009-09-15

    In a matter of a few weeks' time, governments will gather in Copenhagen, Denmark, for a crucial UN climate convention meeting. Many governments and stakeholders have requested an annual snapshot of how the science has been evolving since the publication of the IPCC's landmark fourth assessment in advance of the panel's next one in 2014. This Climate Change Science Compendium, based on the wealth of peerreviewed research published by researchers and institutions since 2006, has been compiled by UNEP in response to that request. The findings indicate that ever more rapid environmental change is underway with the pace and the scale of climate change accelerating, along with the confidence among researchers in their forecasts. The Arctic, with implications for the globe, is emerging as an area of major concern. There is growing evidence that the ice there is melting far faster than had been previously supposed. Mountains glaciers also appear to be retreating faster. Scientists now suggest that the Arctic could be virtually ice free in September of 2037 and that a nearly ice-free September by 2028 is well within the realms of possibility. Recent findings also show that significant warming extends well beyond the Antarctic Peninsula to cover most of West Antarctica, an area of warming much larger than previously reported. The impact on the Earth's multi-trillion dollar ecosystems is also a key area of concern. Under a high emission scenario-the one that most closely matches current trends-12-39 per cent of the planet's terrestrial surface could experience novel climate conditions and 10-48 per cent could suffer disappearing climates by 2100. Rising levels of aridity are also concentrating scientific minds. New research indicates that by the end of the 21st century the Mediterranean region will also experience much more severe increases in aridity than previously estimated rendering the entire region, but particularly the southern Mediterranean

  1. Tropical deforestation and climate change

    Energy Technology Data Exchange (ETDEWEB)

    Ebeling, J.

    2006-08-15

    This dissertation evaluates recent proposals to include tropical deforestation into international climate change mitigation strategies. Deforestation is responsible for up to 25 percent of global greenhouse gas emissions. The research aim here is to evaluate implications of a range of policy options for the environmental effectiveness of a prospective agreement, as well as for its political and economic attractiveness for different countries and stakeholders. A literature review, 48 key stakeholder interviews, analyses of submissions to the United Nations Framework Convention on Climate Change (UNFCCC), modelling approaches and statistical analyses were carried out to answer these questions. On this basis the study identifies potential deal breakers and explores possible solutions to existing 'real' and perceived obstacles. Findings suggest that, given sufficient political will, an effective agreement between current UNFCCC Parties is feasible and that existing concerns can be addressed in pragmatic ways. Among the different policy alternatives, creating a new carbon trading mechanism under a post-2012 Kyoto regime is likely to deliver greatest economic and environmental benefits. Measuring emission reductions against national-level baselines based on historical base periods would increase the environmental integrity of resulting carbon credits. The study also finds that potential monetary benefits are distributed very unevenly between potential host countries, and that this may partly explain current negotiation positions. Complementary approaches, not based on emission trading, may have to be developed to foster broader support for an agreement. Finally, setting more ambitious emission reduction targets for industrialised countries would overcome concerns about 'flooding' of carbon markets, and would make the most of a unique opportunity to tackle both climate change and deforestation.

  2. Can beaches survive climate change?

    Science.gov (United States)

    Vitousek, Sean; Barnard, Patrick L.; Limber, Patrick

    2017-04-01

    Anthropogenic climate change is driving sea level rise, leading to numerous impacts on the coastal zone, such as increased coastal flooding, beach erosion, cliff failure, saltwater intrusion in aquifers, and groundwater inundation. Many beaches around the world are currently experiencing chronic erosion as a result of gradual, present-day rates of sea level rise (about 3 mm/year) and human-driven restrictions in sand supply (e.g., harbor dredging and river damming). Accelerated sea level rise threatens to worsen coastal erosion and challenge the very existence of natural beaches throughout the world. Understanding and predicting the rates of sea level rise and coastal erosion depends on integrating data on natural systems with computer simulations. Although many computer modeling approaches are available to simulate shoreline change, few are capable of making reliable long-term predictions needed for full adaption or to enhance resilience. Recent advancements have allowed convincing decadal to centennial-scale predictions of shoreline evolution. For example, along 500 km of the Southern California coast, a new model featuring data assimilation predicts that up to 67% of beaches may completely erode by 2100 without large-scale human interventions. In spite of recent advancements, coastal evolution models must continue to improve in their theoretical framework, quantification of accuracy and uncertainty, computational efficiency, predictive capability, and integration with observed data, in order to meet the scientific and engineering challenges produced by a changing climate.

  3. Can beaches survive climate change?

    Science.gov (United States)

    Vitousek, Sean; Barnard, Patrick L.; Limber, Patrick W.

    2017-01-01

    Anthropogenic climate change is driving sea level rise, leading to numerous impacts on the coastal zone, such as increased coastal flooding, beach erosion, cliff failure, saltwater intrusion in aquifers, and groundwater inundation. Many beaches around the world are currently experiencing chronic erosion as a result of gradual, present-day rates of sea level rise (about 3 mm/year) and human-driven restrictions in sand supply (e.g., harbor dredging and river damming). Accelerated sea level rise threatens to worsen coastal erosion and challenge the very existence of natural beaches throughout the world. Understanding and predicting the rates of sea level rise and coastal erosion depends on integrating data on natural systems with computer simulations. Although many computer modeling approaches are available to simulate shoreline change, few are capable of making reliable long-term predictions needed for full adaption or to enhance resilience. Recent advancements have allowed convincing decadal to centennial-scale predictions of shoreline evolution. For example, along 500 km of the Southern California coast, a new model featuring data assimilation predicts that up to 67% of beaches may completely erode by 2100 without large-scale human interventions. In spite of recent advancements, coastal evolution models must continue to improve in their theoretical framework, quantification of accuracy and uncertainty, computational efficiency, predictive capability, and integration with observed data, in order to meet the scientific and engineering challenges produced by a changing climate.

  4. Climate change: linking traditional and scientific knowledge

    National Research Council Canada - National Science Library

    Riewe, R. R. (Roderick R.); Oakes, Jill E. (Jill Elizabeth)

    2006-01-01

    This book includes papers written by over 50 community experts and scientists addressing theoretical concerns, knowledge transfer, adapting to climate change, implications of changing weather, water...

  5. Climate change & health: the case for sustainable development.

    Science.gov (United States)

    Wilkinson, Paul

    2008-01-01

    The Earth's climate has been stable for around 10,000 years, though it has been very variable in earlier periods and has occasionally changed abruptly through natural processes. Industrialization and population growth have brought an exponential rise in the use of carbonaceous fuels, which is now having an observable impact on the composition of the atmosphere. Carbon dioxide levels are already substantially above pre-industrial levels, and rising appreciably year on year. Climate models suggest that the anthropogenic rise in carbon dioxide and other greenhouse gases will lead to rapid climate change over the twenty-first century, with an increase in global average temperatures in the region of two to five degrees Celsius. This will present problems of adaptation for many natural systems and have largely negative effects on human health through both direct and indirect mechanisms. There is also a possibility of unpredicted catastrophic impacts arising from non-linear effects of climate change, which may have more damaging effects on human and other populations. Policy responses have to be directed towards both adaptation needs and mitigation. Mitigation in particular presents formidable social, political and technological challenges, but it may bring net health benefits in the short as well as the longer term.

  6. Progress in rapid climate changes and their modeling study in millennial and centennial scales

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Rapid climate change at millennial and centennial scales is one of the most important aspects in paleoclimate study.It has been found that rapid climate change at millennial and centennial scales is a global phenomenon during both the glacial age and the Holocene with amplitudes typical of geological or astronomical time-scales.Simulations of glacial and Holocene climate changes have demonstrated the response of the climate system to the changes of earth orbital parameter and the importance of variations in feedbacks of ocean,vegetation,icecap and greenhouse gases.Modeling experiments suggest that the Atlantic thermohaline circulation was sensitive to the fresh water input into the North Atlantic and was closely related to the rapid climate changes during the last glacial age and the Holocene.Adopting the Earth-system models of inter mediate complexity (EMICs),CLIMBER-2,the response of East Asian climate change to Dansgaard/Oeschger and Heinrich events during the typical last glacial period (60 ka B.P.-20 ka B.P.) and impacts of ice on the Tibetan plateau on Holocene climate change were stimulated,studied and revealed.Further progress of paleoclimate modeling depends on developing finer-grid models and reconstructing more reliable boundary conditions.More attention should be paid on the study of mechanisms of abrupt climatic changes as well as regional climate changes in the background of global climate change.

  7. Climate Change and Corporate Environmental Responsibility

    OpenAIRE

    Dewan Mahboob HOSSAIN; Chowdhury, M. Jahangir Alam

    2012-01-01

    Climate change, as an international environmental issue, is getting a lot of attention. The negative effects of climate change have become one of the most talked about issues among Governments, scientists, environmentalists and others. It is said that business activities are affecting the climate negatively. In order to minimize the negative effects of climate change, the activities of the businesses should be controlled and encouraged to perform in a socially responsible manner. The article ...

  8. Groundwater and climate change research scoping study

    OpenAIRE

    Jackson, C. R.; Cheetham, M.; Guha, P

    2006-01-01

    This scoping study has reviewed much of the published literature in the field of climate change and groundwater research. Whilst it is not exhaustive with regard to groundwater quality issues, most of the published literature relating to climate change and groundwater resources, particularly in the UK, is covered. Further work is required to identify current research needs relating to the effects of climate change on groundwater quality. The study of the effects of climate chan...

  9. India's National Action Plan on Climate Change

    OpenAIRE

    Pandve, Harshal T.

    2009-01-01

    Climate change is one of the most critical global challenges of our times. Recent events have emphatically demonstrated our growing vulnerability to climate change. Climate change impacts will range from affecting agriculture – further endangering food security – to sea-level rise and the accelerated erosion of coastal zones, increasing intensity of natural disasters, species extinction, and the spread of vector-borne diseases. India released its much-awaited National Action Plan on Climate C...

  10. A history of climate change

    DEFF Research Database (Denmark)

    Hastrup, Kirsten Blinkenberg

    2017-01-01

    they were first described and became known to outsiders, it is shown how flexibility and mobility were always preconditions for survival in this environment. Then, they were trapped in too much ice, while now they have to negotiate a rapidly melting environment. In both cases their response is deeply......This article presents a small community of High Arctic hunters (the Inughuit in North West Greenland) who have always had to negotiate climatic changes with great impact on their living conditions. This points us toward the natural-social entanglements implied in the notion of the Anthropocene...

  11. Regional climate change mitigation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rowlands, Ian H. [UNEP Collaborating Centre on Energy and Environment, and Univ. of Waterloo (Canada)

    1998-10-01

    The purpose of this paper is to explore some of the key methodological issues that arise from an analysis of regional climate change mitigation options. The rationale for any analysis of regional mitigation activities, emphasising both the theoretical attractiveness and the existing political encouragement and the methodology that has been developed are reviewed. The differences arising from the fact that mitigation analyses have been taken from the level of the national - where the majority of the work has been completed to date - to the level of the international - that is, the `regional` - will be especially highlighted. (EG)

  12. Renewable energy and climate change

    CERN Document Server

    Quaschning, Volker

    2010-01-01

    This dazzling introductory textbook encompasses the full range of today's important renewable energy technologies. Solar thermal, photovoltaic, wind, hydro, biomass and geothermal energy receive balanced treatment with one exciting and informative chapter devoted to each. As well as a complete overview of these state-of-the-art technologies, the chapters provide: clear analysis on their development potentials; an evaluation of the economic aspects involved; concrete guidance for practical implementation; how to reduce your own energy waste. If we do not act now to stop climate change, the cons.

  13. Virgin's Knight tackles climate change

    Science.gov (United States)

    Banks, Michael

    2008-11-01

    "There is no greater or more immediate challenge than that posed by climate change," said Sir Richard Branson, chairman of the Virgin group, via video-link at the 59th International Astronautical Congress (IAC) held in Glasgow in the UK at the end of September. That grand statement may seem like a lot of hot air for the entrepreneur best known for his attempt to circumnavigate the globe by balloon. But Branson went on to reveal that Virgin Galactic, which aims to fly passengers 100 km into space for 200 000 per trip, will also provide room on its craft for a series of scientific experiments to study the Earth's atmosphere.

  14. The challenges of communicating climate change

    Directory of Open Access Journals (Sweden)

    Emiliano Feresin

    2009-06-01

    Full Text Available The climate change issue has become increasingly present in our society in the last decade and central also to communication studies. In the e-book “Communicating Climate Change: Discourses, Mediations and Perceptions”, edited by Anabela Carvalho, various scholars investigate how climate change challenges communication by looking at three main aspects: the discourses of a variety of social actors on climate change; the reconstruction of those discourses in the media; the citizens’ perceptions, understandings and attitudes in relation to climate change.

  15. Climate change and nutrition: creating a climate for nutrition security.

    Science.gov (United States)

    Tirado, M C; Crahay, P; Mahy, L; Zanev, C; Neira, M; Msangi, S; Brown, R; Scaramella, C; Costa Coitinho, D; Müller, A

    2013-12-01

    Climate change further exacerbates the enormous existing burden of undernutrition. It affects food and nutrition security and undermines current efforts to reduce hunger and promote nutrition. Undernutrition in turn undermines climate resilience and the coping strategies of vulnerable populations. The objectives of this paper are to identify and undertake a cross-sectoral analysis of the impacts of climate change on nutrition security and the existing mechanisms, strategies, and policies to address them. A cross-sectoral analysis of the impacts of climate change on nutrition security and the mechanisms and policies to address them was guided by an analytical framework focused on the three 'underlying causes' of undernutrition: 1) household food access, 2) maternal and child care and feeding practices, 3) environmental health and health access. The analytical framework includes the interactions of the three underlying causes of undernutrition with climate change,vulnerability, adaptation and mitigation. Within broad efforts on climate change mitigation and adaptation and climate-resilient development, a combination of nutrition-sensitive adaptation and mitigation measures, climate-resilient and nutrition-sensitive agricultural development, social protection, improved maternal and child care and health, nutrition-sensitive risk reduction and management, community development measures, nutrition-smart investments, increased policy coherence, and institutional and cross-sectoral collaboration are proposed as a means to address the impacts of climate change to food and nutrition security. This paper proposes policy directions to address nutrition in the climate change agenda and recommendations for consideration by the UN Framework Convention on Climate Change (UNFCCC). Nutrition and health stakeholders need to be engaged in key climate change adaptation and mitigation initiatives, including science-based assessment by the Intergovernmental Panel on Climate Change (IPCC

  16. Role of scale interactions in the abrupt change of tropical cyclone in autumn over the Western North Pacific

    Science.gov (United States)

    Hsu, Pang-Chi; Lee, Ting-Hui; Tsou, Chih-Hua; Chu, Pao-Shin; Qian, Yitian; Bi, Mingyu

    2017-01-01

    Tropical cyclone (TC) activity in autumn (September-November) over the western North Pacific experienced an abrupt change in 1998, which can be detected by the Bayesian change-point analysis. During the decade before the regime shift (1988-1997), the occurrence frequency of TC genesis increased significantly over the tropical western Pacific, where the seasonal cyclonic flow, intraseasonal oscillation (ISO) and synoptic-scale eddy (SSE) were all strengthened, compared to those observed in the decade after 1998 (1998-2007). The TC trajectories also exhibited spatial differences. During the active decade, the TCs had a higher probability to move westward into the Philippine Sea and the South China Sea, and recurved northeastward toward the east of Japan. Meanwhile, the northwestward propagating TCs approaching Taiwan and southeastern coast of China were reduced. To understand the role of mean flow-ISO-SSE interaction in the decadal changes of SSE and associated TC activity, we diagnosed a newly proposed SSE kinetic energy (KE) equation that separates the contributions of seasonal-mean circulation and ISO to the SSE. The results show that, during the active TC decade, the SSE obtained higher KE from both mean flow and ISO through eddy barotropic energy conversion when the enhanced SSE momentum flux interacted with the strengthened monsoon trough and vigorous ISO cyclonic anomaly over the western tropical Pacific. The increased SSE KE contributed positively to the increased TC genesis over the main genesis region (7.5°-20°N, 130°-170°E). It also benefited the growth of TCs over the Philippine Sea and the South China Sea during the active decade. The decadal change in TC frequency over the extratropics was related to the eddy baroclinic energy conversion instead of the barotropic conversion associated with scale interaction. During the active TC decade, SSE gained more (less) KE from the SSE available potential energy over the east of Japan (the East China Sea

  17. Knowledge Exchange Within the Rapid Climate Change Program (RAPID)

    Science.gov (United States)

    Wallace, C.; Srokosz, M.

    2008-12-01

    The Rapid Climate Change Program (RAPID) is a major UK-led science program investigating the susceptibility to and risk of abrupt change in the climate system, with a particular focus on the role of the Atlantic Meridional Overturning Circulation (AMOC). RAPID commenced in 2001, with initial funding to 2008 and has just entered its second phase - RAPID-WATCH - extending some aspects of the program until 2014. Scientifically, a key focus of the program has concerned the development and deployment of a continuous AMOC observing system, although the program has also supported research into a number of other aspects of rapid climate change, including paleo studies of past rapid changes, modeling of the past and future climate, and the development of methods with which to aid the quantification of future risks. Given the societal implications that abrupt climate change associated with the AMOC may have for the North Atlantic region, a major focus within the program has been the implementation of a Knowledge Exchange strategy with which to engage key decision and policy makers within the UK political and industrial sectors. This interaction is especially pertinent for those decision makers involved in the development of adaptive capacities that must incorporate resilience to so-called high-impact, low-probability class threats. We will summarize here the main aspects of our approach, outlining activities/methods used both to satisfy the obvious need to transfer key scientific findings from the program to users, but also in facilitating a return flow of knowledge which can be used by scientists to refine the impact and utility of scientific output. We will draw on particular experience gained from the program's involvement in i: personnel exchanges with central government departments; ii: interaction and co-operation with third party stakeholder organizations (e.g. the UK Climate Impacts Program); and iii: provision of written and oral briefings. Throughout, techniques

  18. Adaptation to Climate Change in Developing Countries

    DEFF Research Database (Denmark)

    Mertz, Ole; Halsnæs, Kirsten; Olesen, Jørgen E.

    2009-01-01

    Adaptation to climate change is given increasing international attention as the confidence in climate change projections is getting higher. Developing countries have specific needs for adaptation due to high vulnerabilities, and they will in this way carry a great part of the global costs...... of climate change although the rising atmospheric greenhouse gas concentrations are mainly the responsibility of industrialized countries. This article provides a status of climate change adaptation in developing countries. An overview of observed and projected climate change is given, and recent literature...... on impacts, vulnerability, and adaptation are reviewed, including the emerging focus on mainstreaming of climate change and adaptation in development plans and programs. The article also serves as an introduction to the seven research articles of this special issue on climate change adaptation in developing...

  19. Challenges and solutions for climate change

    CERN Document Server

    Gaast, Wytze

    2012-01-01

    The latest scientific knowledge on climate change indicates that higher greenhouse gas concentrations in the atmosphere through unchecked emissions will provoke severe climate change and ocean acidification threatening environmental structures on which humanity relies. Climate change therefore poses major socio-economic, technical and environmental challenges which will have serious impacts on countries’ pathways towards sustainable development. As a result, climate change and sustainable development have increasingly become interlinked. A changing climate makes achieving Millennium Development Goals more difficult and expensive, so there is every reason to achieve development goals with low greenhouse gas emissions. This leads to the following five challenges discussed by Challenges and Solutions for Climate Change: To place climate negotiations in the wider context of sustainability, equity and social change so that development benefits can be maximised at the same time as decreasing greenhouse gas emissi...

  20. Overview of different aspects of climate change effects on soils

    Energy Technology Data Exchange (ETDEWEB)

    Qafoku, Nikolla P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-08-01

    Climate change [i.e., high atmospheric carbon dioxide (CO2) concentrations (≥400 ppm); increasing air temperatures (2-4°C or greater); significant and/or abrupt changes in daily, seasonal, and inter-annual temperature; changes in the wet/dry cycles; intensive rainfall and/or heavy storms; extended periods of drought; extreme frost; heat waves and increased fire frequency] is and will significantly affect soil properties and fertility, water resources, food quantity and quality, and environmental quality. Biotic processes that consume atmospheric CO2 and create organic carbon (C) that is either reprocessed to CO2 or stored in soils, are the subject of active current investigations with great concern over the influence of climate change. In addition, abiotic C cycling and its influence on the inorganic C pool in soils is a fundamental global process in which acidic atmospheric CO2 participates in the weathering of carbonate and silicate minerals, ultimately delivering bicarbonate and Ca2+ or other cations that precipitate in the form of carbonates in soils or are transported to the rivers, lakes, and oceans. Soil responses to climate change will be complex, and there are many uncertainties and unresolved issues. The objective of the review is to initiate and further stimulate a discussion about some important and challenging aspects of climate-change effects on soils, such as accelerated weathering of soil minerals and resulting C and elemental fluxes in and out of soils, soil/geo-engineering methods used to increase C sequestration in soils, soil organic matter (SOM) protection, transformation and mineralization, and SOM temperature sensitivity. This review reports recent discoveries and identifies key research needs required to understand the effects of climate change on soils.

  1. Overview of different aspects of climate change effects on soils.

    Energy Technology Data Exchange (ETDEWEB)

    Qafoku, Nikolla

    2014-08-01

    Climate change [i.e., high atmospheric carbon dioxide (CO2) concentrations (≥400 ppm); increasing air temperatures (2-4°C or greater); significant and/or abrupt changes in daily, seasonal, and inter-annual temperature; changes in the wet/dry cycles; intensive rainfall and/or heavy storms; extended periods of drought; extreme frost; heat waves and increased fire frequency] is and will significantly affect soil properties and fertility, water resources, food quantity and quality, and environmental quality. Biotic processes that consume atmospheric CO2 and create organic carbon (C) that is either reprocessed to CO2 or stored in soils, are the subject of active current investigations with great concern over the influence of climate change. In addition, abiotic C cycling and its influence on the inorganic C pool in soils is a fundamental global process in which acidic atmospheric CO2 participates in the weathering of carbonate and silicate minerals, ultimately delivering bicarbonate and Ca2+ or other cations that precipitate in the form of carbonates in soils or are transported to the rivers, lakes, and oceans. Soil responses to climate change will be complex, and there are many uncertainties and unresolved issues. The objective of the review is to initiate and further stimulate a discussion about some important and challenging aspects of climate-change effects on soils, such as accelerated weathering of soil minerals and resulting C and elemental fluxes in and out of soils, soil/geo-engineering methods used to increase C sequestration in soils, soil organic matter (SOM) protection, transformation and mineralization, and SOM temperature sensitivity. This review reports recent discoveries and identifies key research needs required to understand the effects of climate change on soils.

  2. Climate Change Adaptation in the Water Sector

    NARCIS (Netherlands)

    Ludwig, F.; Kabat, P.; Schaik, van H.; Valk, van der M.

    2009-01-01

    Today’s climate variability already has a large impact on water supply and protection. Millions of people are affected every year by droughts and floods. Future climate change is likely to make things worse. Many people within the water sector are aware that climate change is affecting water resourc

  3. Climate Change and Public Health Policy.

    Science.gov (United States)

    Smith, Jason A; Vargo, Jason; Hoverter, Sara Pollock

    2017-03-01

    Climate change poses real and immediate impacts to the public health of populations around the globe. Adverse impacts are expected to continue throughout the century. Emphasizing co-benefits of climate action for health, combining adaptation and mitigation efforts, and increasing interagency coordination can effectively address both public health and climate change challenges.

  4. Climate Change Adaptation in the Water Sector

    NARCIS (Netherlands)

    Ludwig, F.; Kabat, P.; Schaik, van H.; Valk, van der M.

    2009-01-01

    Today’s climate variability already has a large impact on water supply and protection. Millions of people are affected every year by droughts and floods. Future climate change is likely to make things worse. Many people within the water sector are aware that climate change is affecting water

  5. Turning points in climate change adaptation

    NARCIS (Netherlands)

    Werners, Saskia Elisabeth; Slobbe, van Erik; Bölscher, Tobias; Oost, Albert; Pfenninger, Stefan; Trombi, Giacomo; Bindi, Marco; Moriondo, Marco

    2015-01-01

    Concerned decision makers increasingly pose questions as to whether current management practices are able to cope with climate change and increased climate variability. This signifies a shift in the framing of climate change from asking what its potential impacts are to asking whether it induces

  6. Turning points in climate change adaptation

    NARCIS (Netherlands)

    Werners, Saskia Elisabeth; van Slobbe, Erik; Bölscher, Tobias; Oost, Albert; Pfenninger, Stefan; Trombi, Giacomo; Bindi, Marco; Moriondo, Marco

    2015-01-01

    Concerned decision makers increasingly pose questions as to whether current management practices are able to cope with climate change and increased climate variability. This signifies a shift in the framing of climate change from asking what its potential impacts are to asking whether it induces pol

  7. Science Teachers' Perspectives about Climate Change

    Science.gov (United States)

    Dawson, Vaille

    2012-01-01

    Climate change and its effects are likely to present challenging problems for future generations of young people. It is important for Australian students to understand the mechanisms and consequences of climate change. If students are to develop a sophisticated understanding, then science teachers need to be well-informed about climate change…

  8. Science Teachers' Perspectives about Climate Change

    Science.gov (United States)

    Dawson, Vaille

    2012-01-01

    Climate change and its effects are likely to present challenging problems for future generations of young people. It is important for Australian students to understand the mechanisms and consequences of climate change. If students are to develop a sophisticated understanding, then science teachers need to be well-informed about climate change…

  9. Climate change. Scientific background and process

    Energy Technology Data Exchange (ETDEWEB)

    Alfsen, Knut H.; Fuglestvedt, Jan; Seip, Hans Martin; Skodvin, Tora

    1999-07-01

    The paper describes briefly the natural and man-made forces behind climate change and outlines climate variations in the past. It also discusses the future impact of anthropogenic emission of greenhouse gases, and the background, organisation and functioning of the Intergovernmental Panel on Climate Change (IPCC)

  10. Contributions of Psychology to Limiting Climate Change

    Science.gov (United States)

    Stern, Paul C.

    2011-01-01

    Psychology can make a significant contribution to limiting the magnitude of climate change by improving understanding of human behaviors that drive climate change and human reactions to climate-related technologies and policies, and by turning that understanding into effective interventions. This article develops a framework for psychological…

  11. A Novel Approach to Detect Symmetrical Faults Occurring During Power Swings by Using Abrupt change of Impedance Trajectory

    DEFF Research Database (Denmark)

    Khodaparast, Jalal; Silva, Filipe Miguel Faria da; Bak, Claus Leth;

    2017-01-01

    The main purpose of power swing blocking is to distinguish faults from power swings. However, faults occurred during a power swing should still be detected and cleared promptly. This paper proposes an index based on detecting abrupt jump of impedance trajectory by utilization of predicting capabi...

  12. Climate change: believing and seeing implies adapting.

    Science.gov (United States)

    Blennow, Kristina; Persson, Johannes; Tomé, Margarida; Hanewinkel, Marc

    2012-01-01

    Knowledge of factors that trigger human response to climate change is crucial for effective climate change policy communication. Climate change has been claimed to have low salience as a risk issue because it cannot be directly experienced. Still, personal factors such as strength of belief in local effects of climate change have been shown to correlate strongly with responses to climate change and there is a growing literature on the hypothesis that personal experience of climate change (and/or its effects) explains responses to climate change. Here we provide, using survey data from 845 private forest owners operating in a wide range of bio-climatic as well as economic-social-political structures in a latitudinal gradient across Europe, the first evidence that the personal strength of belief and perception of local effects of climate change, highly significantly explain human responses to climate change. A logistic regression model was fitted to the two variables, estimating expected probabilities ranging from 0.07 (SD ± 0.01) to 0.81 (SD ± 0.03) for self-reported adaptive measures taken. Adding socio-demographic variables improved the fit, estimating expected probabilities ranging from 0.022 (SD ± 0.008) to 0.91 (SD ± 0.02). We conclude that to explain and predict adaptation to climate change, the combination of personal experience and belief must be considered.

  13. [Climate change and Kyoto protocol].

    Science.gov (United States)

    Ergasti, G; Pippia, V; Murzilli, G; De Luca D'Alessandro, E

    2009-01-01

    Due to industrial revolution and the heavy use of fossil fuels, the concentration of greenhouse gases in the atmosphere has increased dramatically during the last hundred years, and this has lead to an increase in mean global temperature. The environmental consequences of this are: the melting of the ice caps, an increase in mean sea-levels, catastrophic events such as floodings, hurricanes and earthquakes, changes to the animal and vegetable kingdoms, a growth in vectors and bacteria in water thus increasing the risk of infectious diseases and damage to agriculture. The toxic effects of the pollution on human health are both acute and chronic. The Kyoto Protocol is an important step in the campaign against climatic changes but it is not sufficient. A possible solution might be for the States which produce the most of pollution to adopt a better political stance for the environment and to use renewable resources for the production of energy.

  14. Rethinking climate change as a security threat

    Energy Technology Data Exchange (ETDEWEB)

    Schoch, Corinne

    2011-10-15

    Once upon a time climate change was a strictly environment and development issue. Today it has become a matter of national and international security. Efforts to link climate change with violent conflict may not be based on solid evidence, but they have certainly captured the attention of governments. They have played a vital role in raising the much-needed awareness of climate change as an issue that deserves global action. But at what cost? Focusing on climate change as a security threat alone risks devolving humanitarian responsibilities to the military, ignoring key challenges and losing sight of those climate-vulnerable communities that stand most in need of protection.

  15. Quantitative approaches in climate change ecology

    DEFF Research Database (Denmark)

    Brown, Christopher J.; Schoeman, David S.; Sydeman, William J.

    2011-01-01

    climate variability and other drivers of change. To assist the development of reliable statistical approaches, we review the marine climate change literature and provide suggestions for quantitative approaches in climate change ecology. We compiled 267 peer‐reviewed articles that examined relationships...... between climate change and marine ecological variables. Of the articles with time series data (n = 186), 75% used statistics to test for a dependency of ecological variables on climate variables. We identified several common weaknesses in statistical approaches, including marginalizing other important non...

  16. Pregnancy Complications: Placental Abruption

    Science.gov (United States)

    ... wall of the uterus (womb) and supplies the baby with food and oxygen through the umbilical cord. Placental abruption ... wall of the uterus (womb) and supplies the baby with food and oxygen through the umbilical cord. Placental abruption ...

  17. Preparing Australian medical students for climate change.

    Science.gov (United States)

    Green, Evelyn I Hamel; Blashki, Grant; Berry, Helen L; Harley, David; Horton, Graeme; Hall, Gillian

    2009-09-01

    Climate change is now recognised as a global public health problem and the future medical workforce will be working during a period when the health impacts of climate change are likely to be significant. This article discusses the ongoing training on the health impacts of climate change for the current and future medical workforce. The role of medical practitioners in the coming decades will need to include assisting communities to adapt to changing climatic conditions, managing climate sensitive illnesses, and contributing to mitigation efforts to prevent climate change. Climate change and health should be built into the curricula of Australian medical schools spanning public health, clinical medicine, preventive health and global health. We propose a problem based learning approach to highlight clinical and public health implications, and present two hypothetical case studies suitable for teaching purposes.

  18. The human factor: climate change and climate communication

    DEFF Research Database (Denmark)

    2011-01-01

    Reprint and translation of the article: “Den menneskelige faktor” published in the magazine Klima&Tilpasning Publisher: “Coordination unit for Research in Climate Change Adaptation” (KFT)......Reprint and translation of the article: “Den menneskelige faktor” published in the magazine Klima&Tilpasning Publisher: “Coordination unit for Research in Climate Change Adaptation” (KFT)...

  19. Climate Cases: Learning about Student Conceptualizations of Global Climate Change

    Science.gov (United States)

    Tierney, Benjamin P.

    2013-01-01

    The complex topic of global climate change continues to be a challenging yet important topic among science educators and researchers. This mixed methods study adds to the growing research by investigating student conceptions of climate change from a system theory perspective (Von Bertalanffy, 1968) by asking the question, "How do differences…

  20. Climate Cases: Learning about Student Conceptualizations of Global Climate Change

    Science.gov (United States)

    Tierney, Benjamin P.

    2013-01-01

    The complex topic of global climate change continues to be a challenging yet important topic among science educators and researchers. This mixed methods study adds to the growing research by investigating student conceptions of climate change from a system theory perspective (Von Bertalanffy, 1968) by asking the question, "How do differences…