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Sample records for climate change sea

  1. The role of sea ice dynamics in global climate change

    NASA Technical Reports Server (NTRS)

    Hibler, William D., III

    1992-01-01

    The topics covered include the following: general characteristics of sea ice drift; sea ice rheology; ice thickness distribution; sea ice thermodynamic models; equilibrium thermodynamic models; effect of internal brine pockets and snow cover; model simulations of Arctic Sea ice; and sensitivity of sea ice models to climate change.

  2. Projected climate change impacts to the North Sea marine system

    NASA Astrophysics Data System (ADS)

    Schrum, Corinna

    2015-04-01

    Future climate change impacts to the North Sea marine system are driven by a combination of changes induced by the globally forced oceanic boundary conditions and the regional atmospheric and terrestrial changes. We reviewed the recent progress and the projected future change of the North Sea marine system as part of the North Sea Climate Change Assessment (NOSCCA) and focussed on three major aspects, namely the change of (i) sea level, the (ii) hydrographic and circulation changes of the North Sea and the (iii) changes in lower trophic level dynamics, biogeochemistry and ocean acidification. In recent years more and more regional climate change assessments became available for the North Sea and new developments contributed important understanding on regional processes mediating climate change impacts in the North Sea. Important new knowledge on regional future sea level change was gained by improved understanding of processes contributing to global sea level rise during the last decade. Assessment of climate change impacts to hydrography, circulation and biogeochemistry has benefited from new and advanced downscaling methods. The large number of regional studies enables now a critical review of the current knowledge on climate change impacts on the North Sea and allows the identification of challenges, robust changes, uncertainties and specific recommendations for future research. The long term trends in the climate conditions are superposed on the natural modes of variability and separating these to give a clear anthropogenic climate change signal is one of the 'grand challenges' of climate change impact studies in marine regions and of particular relevance for North Sea. The impact of natural variability on future annual average steric sea level, sea surface temperature and ocean acidification is less dominant compared to the climate change signal and their projected changes for the North Sea, namely rising future sea level, increasing surface temperature and

  3. Sea-ice switches and abrupt climate change.

    PubMed

    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.

  4. Sea-ice switches and abrupt climate change.

    PubMed

    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. PMID:14558902

  5. NASA Now: Climate Change: Sea Level Rise

    NASA Video Gallery

    Dr. Josh Willis discusses the connection between oceans and global climate change. Learn why NASA measures greenhouse gases and how we detect ocean levels from space. These are crucial vital signs ...

  6. On how climate variability influences regional sea level change

    NASA Astrophysics Data System (ADS)

    Brunnabend, Sandra-Esther; Kusche, Jürgen; Rietbroek, Roelof; Forootan, Ehsan

    2016-04-01

    Regional trends in sea level change are strongly influenced by climate variations, such as ENSO (El-Nino Southern Oscillation), the IOD (Indian Ocean Dipole), or the PDO (Pacific Decadal Oscillation). Hence, before computing long term regional sea level change, these sea level variations need to be taken into account as they lead to strong dependencies of computed regional sea level trends on the time period of the investigation. In this study, sea level change during the years 1993 to 2013 is analysed to identify the dominant modes of sea level change caused by climate variations. Here, two different gridded altimetry products are analysed, namely ESA's combined CCI SeaLevel v1.1 ECV product (doi: 10.5270/esa-sea_level_cci-1993_2013-v_1.1-201412), and absolute dynamic topography produced by Ssalto/Duacs and distributed by Aviso, with support from Cnes (http://www.aviso.altimetry.fr/duacs/). Reconstructions using the different decomposition techniques including the standard principle component analysis (PCA), rotated empirical orthogonal functions (REOF) and independent component analysis (ICA) method are analysed. They are compared with sea level change modelled with the global finite-element sea-ice ocean model (FESOM). The results indicate that from the applied methods, ICA is most suitable to separate the individual climate variability signals in independent modes of sea level change. This especially holds for extracting the ENSO contribution in sea level changes, which was better separated by applying ICA, from both altimetry and modelled sea level products. In addition, it is presented how modelled sea level change reflects climate variations compared to that identified in the altimetry products.

  7. Future Climate Change in the Baltic Sea Area

    NASA Astrophysics Data System (ADS)

    Bøssing Christensen, Ole; Kjellström, Erik; Zorita, Eduardo; Sonnenborg, Torben; Meier, Markus; Grinsted, Aslak

    2015-04-01

    Regional climate models have been used extensively since the first assessment of climate change in the Baltic Sea region published in 2008, not the least for studies of Europe (and including the Baltic Sea catchment area). Therefore, conclusions regarding climate model results have a better foundation than was the case for the first BACC report of 2008. This presentation will report model results regarding future climate. What is the state of understanding about future human-driven climate change? We will cover regional models, statistical downscaling, hydrological modelling, ocean modelling and sea-level change as it is projected for the Baltic Sea region. Collections of regional model simulations from the ENSEMBLES project for example, financed through the European 5th Framework Programme and the World Climate Research Programme Coordinated Regional Climate Downscaling Experiment, have made it possible to obtain an increasingly robust estimation of model uncertainty. While the first Baltic Sea assessment mainly used four simulations from the European 5th Framework Programme PRUDENCE project, an ensemble of 13 transient regional simulations with twice the horizontal resolution reaching the end of the 21st century has been available from the ENSEMBLES project; therefore it has been possible to obtain more quantitative assessments of model uncertainty. The literature about future climate change in the Baltic Sea region is largely built upon the ENSEMBLES project. Also within statistical downscaling, a considerable number of papers have been published, encompassing now the application of non-linear statistical models, projected changes in extremes and correction of climate model biases. The uncertainty of hydrological change has received increasing attention since the previous Baltic Sea assessment. Several studies on the propagation of uncertainties originating in GCMs, RCMs, and emission scenarios are presented. The number of studies on uncertainties related to

  8. Abrupt climate change and collapse of deep-sea ecosystems

    USGS Publications Warehouse

    Yasuhara, Moriaki; Cronin, T. M.; Demenocal, P.B.; Okahashi, H.; Linsley, B.K.

    2008-01-01

    We investigated the deep-sea fossil record of benthic ostracodes during periods of rapid climate and oceanographic change over the past 20,000 years in a core from intermediate depth in the northwestern Atlantic. Results show that deep-sea benthic community "collapses" occur with faunal turnover of up to 50% during major climatically driven oceanographic changes. Species diversity as measured by the Shannon-Wiener index falls from 3 to as low as 1.6 during these events. Major disruptions in the benthic communities commenced with Heinrich Event 1, the Inter-Aller??d Cold Period (IACP: 13.1 ka), the Younger Dryas (YD: 12.9-11.5 ka), and several Holocene Bond events when changes in deep-water circulation occurred. The largest collapse is associated with the YD/IACP and is characterized by an abrupt two-step decrease in both the upper North Atlantic Deep Water assemblage and species diversity at 13.1 ka and at 12.2 ka. The ostracode fauna at this site did not fully recover until ???8 ka, with the establishment of Labrador Sea Water ventilation. Ecologically opportunistic slope species prospered during this community collapse. Other abrupt community collapses during the past 20 ka generally correspond to millennial climate events. These results indicate that deep-sea ecosystems are not immune to the effects of rapid climate changes occurring over centuries or less. ?? 2008 by The National Academy of Sciences of the USA.

  9. Projected changes to Tasman Sea eddies in a future climate

    NASA Astrophysics Data System (ADS)

    Oliver, Eric C. J.; O'Kane, Terence J.; Holbrook, Neil J.

    2015-11-01

    The Tasman Sea is a hot spot of ocean warming, that is linked to the increased poleward influence of the East Australian Current (EAC) over recent decades. Specifically, the EAC produces mesoscale eddies which have significant impacts on the physical, chemical, and biological properties of the Tasman Sea. To effectively consider and explain potential eddy changes in the next 50 years, we use high-resolution dynamically downscaled climate change simulations to characterize the projected future marine climate and mesoscale eddies in the Tasman Sea through the 2060s. We assess changes in the marine climate and the eddy field using bulk statistics and by detecting and tracking individual eddies. We find that the eddy kinetic energy is projected to increase along southeast Australia. In addition, we find that eddies in the projected future climate are composed of a higher proportion of anticyclonic eddies in this region and that these eddies are longer lived and more stable. This amounts to nearly a doubling of eddy-related southward temperature transport in the upper 200 m of the Tasman Sea. These changes are concurrent with increases in baroclinic and barotropic instabilities focused around the EAC separation point. This poleward transport and increase in eddy activity would be expected to also increase the frequency of sudden warming events, including ocean temperature extremes, with potential impacts on marine fisheries, aquaculture, and biodiversity off Tasmania's east coast, through direct warming or competition/predation from invasive migrating species.

  10. Climate change effects on the Baltic Sea borderland between land and sea.

    PubMed

    Strandmark, Alma; Bring, Arvid; Cousins, Sara A O; Destouni, Georgia; Kautsky, Hans; Kolb, Gundula; de la Torre-Castro, Maricela; Hambäck, Peter A

    2015-01-01

    Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.

  11. Physical processes mediating climate change impacts on regional sea ecosystems

    NASA Astrophysics Data System (ADS)

    Holt, J.; Schrum, C.; Cannaby, H.; Daewel, U.; Allen, I.; Artioli, Y.; Bopp, L.; Butenschon, M.; Fach, B. A.; Harle, J.; Pushpadas, D.; Salihoglu, B.; Wakelin, S.

    2014-02-01

    Regional seas are exceptionally vulnerable to climate change, yet are the most directly societally important regions of the marine environment. The combination of widely varying conditions of mixing, forcing, geography (coastline and bathymetry) and exposure to the open-ocean makes these seas subject to a wide range of physical processes that mediates how large scale climate change impacts on these seas' ecosystems. In this paper we explore these physical processes and their biophysical interactions, and the effects of atmospheric, oceanic and terrestrial change on them. Our aim is to elucidate the controlling dynamical processes and how these vary between and within regional seas. We focus on primary production and consider the potential climatic impacts: on long term changes in elemental budgets, on seasonal and mesoscale processes that control phytoplankton's exposure to light and nutrients, and briefly on direct temperature response. We draw examples from the MEECE FP7 project and five regional models systems using ECOSMO, POLCOMS-ERSEM and BIMS_ECO. These cover the Barents Sea, Black Sea, Baltic Sea, North Sea, Celtic Seas, and a region of the Northeast Atlantic, using a common global ocean-atmosphere model as forcing. We consider a common analysis approach, and a more detailed analysis of the POLCOMS-ERSEM model. Comparing projections for the end of the 21st century with mean present day conditions, these simulations generally show an increase in seasonal and permanent stratification (where present). However, the first order (low- and mid-latitude) effect in the open ocean projections of increased permanent stratification leading to reduced nutrient levels, and so to reduced primary production, is largely absent, except in the NE Atlantic. Instead, results show a highly heterogeneous picture of positive and negative change arising from the varying mixing and circulation conditions. Even in the two highly stratified, deep water seas (Black and Baltic Seas) the

  12. Predicting evolutionary responses to climate change in the sea.

    PubMed

    Munday, Philip L; Warner, Robert R; Monro, Keyne; Pandolfi, John M; Marshall, Dustin J

    2013-12-01

    An increasing number of short-term experimental studies show significant effects of projected ocean warming and ocean acidification on the performance on marine organisms. Yet, it remains unclear if we can reliably predict the impact of climate change on marine populations and ecosystems, because we lack sufficient understanding of the capacity for marine organisms to adapt to rapid climate change. In this review, we emphasise why an evolutionary perspective is crucial to understanding climate change impacts in the sea and examine the approaches that may be useful for addressing this challenge. We first consider what the geological record and present-day analogues of future climate conditions can tell us about the potential for adaptation to climate change. We also examine evidence that phenotypic plasticity may assist marine species to persist in a rapidly changing climate. We then outline the various experimental approaches that can be used to estimate evolutionary potential, focusing on molecular tools, quantitative genetics, and experimental evolution, and we describe the benefits of combining different approaches to gain a deeper understanding of evolutionary potential. Our goal is to provide a platform for future research addressing the evolutionary potential for marine organisms to cope with climate change.

  13. Predicting evolutionary responses to climate change in the sea.

    PubMed

    Munday, Philip L; Warner, Robert R; Monro, Keyne; Pandolfi, John M; Marshall, Dustin J

    2013-12-01

    An increasing number of short-term experimental studies show significant effects of projected ocean warming and ocean acidification on the performance on marine organisms. Yet, it remains unclear if we can reliably predict the impact of climate change on marine populations and ecosystems, because we lack sufficient understanding of the capacity for marine organisms to adapt to rapid climate change. In this review, we emphasise why an evolutionary perspective is crucial to understanding climate change impacts in the sea and examine the approaches that may be useful for addressing this challenge. We first consider what the geological record and present-day analogues of future climate conditions can tell us about the potential for adaptation to climate change. We also examine evidence that phenotypic plasticity may assist marine species to persist in a rapidly changing climate. We then outline the various experimental approaches that can be used to estimate evolutionary potential, focusing on molecular tools, quantitative genetics, and experimental evolution, and we describe the benefits of combining different approaches to gain a deeper understanding of evolutionary potential. Our goal is to provide a platform for future research addressing the evolutionary potential for marine organisms to cope with climate change. PMID:24119205

  14. Global mean sea level - Indicator of climate change

    NASA Technical Reports Server (NTRS)

    Robock, A.; Hansen, J.; Gornitz, V.; Lebedeff, S.; Moore, E.; Etkins, R.; Epstein, E.

    1983-01-01

    A critical discussion is presented on the use by Etkins and Epstein (1982) of combined surface air temperature and sea level time series to draw conclusions concerning the discharge of the polar ice sheets. It is objected by Robock that they used Northern Hemisphere land surface air temperature records which are unrepresentative of global sea surface temperature, and he suggests that externally imposed volcanic dust and CO2 forcings can adequately account for observed temperature changes over the last century, with global sea level changing in passive response to sea change as a result of thermal expansion. Hansen et al. adduce evidence for global cooling due to ice discharge that has not exceeded a few hundredths of a degree centigrade in the last century, precluding any importance of this phenomenon in the interpretation of global mean temperature trends for this period. Etkins and Epstein reply that since their 1982 report additional evidence has emerged for the hypothesis that the polar ice caps are diminishing. It is reasserted that each of the indices discussed, including global mean sea surface temperature and sea level, polar ice sheet mass balance, water mass characteristics, and the spin rate and axis of rotation displacement of the earth, are physically linked and can be systematically monitored, as is currently being planned under the auspices of the National Climate Program.

  15. Projected future climate change and Baltic Sea ecosystem management

    NASA Astrophysics Data System (ADS)

    Andersson, Agneta

    2015-04-01

    Climate change is likely to have large effects on the Baltic Sea ecosystem. Simulations indicate 2-4oC warming and 50-80% decreasing ice cover by 2100. Precipitation may increase ~30% in the north, causing increased land runoff of allochthonous organic matter (AOM) and organic pollutants. Salinity will decrease by about 2 units. Coupled physical-biogeochemical models indicate that in the south, bottom-water anoxia may spread, reducing cod recruitment and increasing sediment phosphorus release, promoting cyanobacterial blooms. In the north, heterotrophic bacteria will be favoured by AOM while phytoplankton may become hampered. More trophic levels in the food web will increase energy losses and consequently reduce fish production. Future management of the Baltic Sea must consider effects of climate change on the ecosystem dynamics and functions, as well as effects of anthrophogenic nutrient and pollutant load. Monitoring should have a holistic approach and encompass both autotrophic (phytoplankton) and heterotrophic (e.g. bacterial) processes.

  16. The effect of global climate change on sea level variations along the Bulgarian Black Sea shore

    SciTech Connect

    Mungov, G.; Vesselinov, V.

    1996-12-31

    Data of long-time sea level records along the Bulgarian Black Sea shore are analyzed from the point of view of the global climate change. The analysis of the extreme levels discovers an increase of their appearance during the last 15 years. Two different periods are studied and the recent increases imply the possibility of changes in the regime of the extreme marine events in the Western Black Sea. The cycles in the mean sea levels and the statistical characteristics of the interannual (seasonal) variations are determined. Trends in the sea level records are studied for three basic periods, according the periods in the annual temperature anomalies of the northern hemisphere: 1924--1943; 1944--1973; 1974--1991. The mean sea level rise has maximum value during the first period and minimum during the last third one. This is explained with the decrease of the water inflow into the sea and some initial disturbances in its water balance due to the global climate change. The influence of the global climate change is studied using multiple regression on global environmental data.

  17. Impacts of sea ice / SST changes for the observed climate change -GREENICE project-

    NASA Astrophysics Data System (ADS)

    Ogawa, Fumiaki; Gao, Yongqi; Keenlyside, Noel; Koenigk, Torben; Semenov, Vladimir; Suo, Lingling; Yang, Shuting; Wang, Tao

    2016-04-01

    Under the recent global warming, melting of arctic sea-ice in recent decades could have contributed to recent climate changes including its long-term trend and extreme weather events. While the climatic response to the sea-ice loss have been studied recently, it is still an open question to what extent the sea-ice change has influenced recent climate change. Other factors, such as for example, SST could also have had an influence. A main objective of GREENICE research project is to show what extent of the observed climate trend as well as observed weather extremes could be explained by the change and variability in sea ice and SST, respectively. In this project, we designed two atmospheric general circulation model experiments: In both experiments observed daily sea ice cover variations are prescribed, while for SST, one experiment uses observed daily variations and the other the observed climatology. The experiment is performed by several different state-of-the-art AGCMs. Our preliminary results show that the observed wintertime temperature trend near the surface is poorly reproduced in our hindcast experiments using observed SIC and SST. The impact of SIC variation seems to be confined near the surface, while SST variation seems a key for temperature trend above. It suggests a necessity to consider the atmospheric poleward energy transport associated with SST variation to understand the observed arctic amplification. Other aspects of SIC/SST impact on the observed circulation change such as NAO shall also be discussed.

  18. Changes in Arctic and Antarctic Sea Ice as a Microcosm of Global Climate Change

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.

    2014-01-01

    Polar sea ice is a key element of the climate system and has now been monitored through satellite observations for over three and a half decades. The satellite observations reveal considerable information about polar ice and its changes since the late 1970s, including a prominent downward trend in Arctic sea ice coverage and a much lesser upward trend in Antarctic sea ice coverage, illustrative of the important fact that climate change entails spatial contrasts. The decreasing ice coverage in the Arctic corresponds well with contemporaneous Arctic warming and exhibits particularly large decreases in the summers of 2007 and 2012, influenced by both preconditioning and atmospheric conditions. The increasing ice coverage in the Antarctic is not as readily explained, but spatial differences in the Antarctic trends suggest a possible connection with atmospheric circulation changes that have perhaps been influenced by the Antarctic ozone hole. The changes in the polar ice covers and the issues surrounding those changes have many commonalities with broader climate changes and their surrounding issues, allowing the sea ice changes to be viewed in some important ways as a microcosm of global climate change.

  19. Climate change, sea-level rise, and conservation: keeping island biodiversity afloat.

    PubMed

    Courchamp, Franck; Hoffmann, Benjamin D; Russell, James C; Leclerc, Camille; Bellard, Céline

    2014-03-01

    Island conservation programs have been spectacularly successful over the past five decades, yet they generally do not account for impacts of climate change. Here, we argue that the full spectrum of climate change, especially sea-level rise and loss of suitable climatic conditions, should be rapidly integrated into island biodiversity research and management.

  20. Climate change projection of the Tasman Sea from an Eddy-resolving Ocean Model

    NASA Astrophysics Data System (ADS)

    Matear, R. J.; Chamberlain, M. A.; Sun, C.; Feng, M.

    2013-06-01

    The ocean's western boundary current regions display the greatest rate of twentieth century warming and global climate models project that the accelerated rate of warming will continue with climate change. All existing global climate change projections come from simulations that do not fully resolve either these boundary currents or their eddies. Using an Ocean Eddy-resolving Model (OEM) that captures the dynamics of the East Australian Current (EAC) and its eddies we show the response of the Tasman Sea to climate change differs from what is projected with a coarse resolution Global Climate Model (GCM). With climate change, the OEM projects increased EAC transport with increased eddy activity and an approximately 1° southward latitudinal shift in the point where the EAC separates from the shelf and flows eastward. The OEM increased eddy activity in the Tasman Sea with climate change increases the nutrient supply to the upper ocean and causes an increase in the phytoplankton concentrations and primary productivity by 10% in the oligotrophic waters of the Tasman Sea. The increase in primary productivity is absent in the GCM climate change projection, which projects the region will have a decrease in primary productivity with climate change. Applying the OEM climate change projection for the Tasman Sea to other western boundary current regions suggests the projected intensification of all western boundary currents with climate change should increase eddy activity and provide an important nutrient supply mechanism to counter the increased stratification projected with global warming.

  1. Climate change. How fast are sea levels rising?

    PubMed

    Church, J A

    2001-10-26

    Sea levels are rising as a result of global warming, but assessing the rate of the rise is proving difficult. In his Perspective, Church highlights the report by Cabanes et al., who have reassessed observational data and find that it is closer to model estimates than previously found. However, observational data are still limited and models disagree in their regional projections. With present data and models, regional sea-level changes cannot be predicted with confidence.

  2. North Sea wind climate in changing weather regimes

    NASA Astrophysics Data System (ADS)

    Anders, Ivonne; Rockel, Burkhardt

    2015-04-01

    Results from regional climate models (RCMs) are getting more and more important in future wind climate assessment. From RCMs often only the daily wind speed is available, but no information on prevailing wind direction of each day. Weather regime classification can close this gap and models ability of simulating surface wind speed can be analysed in detail. Several objective regime classifications have been investigated to be a sufficient diagnostic tool to evaluate the present wind climate at the German and Dutch coastal area of the North Sea. The classification by Jenkinson and Collison (1977) uses values for mean sea level pressure at 16 locations centered over the North Sea. Beside the predefined 8 prevailed wind directions and the two possibilities on cyclonic or anticyclonic turbulence, 2x8 hybrid weather types can be defined. In this way 27 different regimes can be distinguished including a class of non-classifiable cases. The 27 regimes could be reduced to a number of 11 by allotting the hybrid types to the directional or the centered types. As the classification is carried out for the North Sea based on ERA40 mean sea level pressure the different regimes clearly reflect the mean wind characteristics at the stations. Comparing the wind roses for the individual observations leads to the assumption that the regime classification described before fits the requirements to carry out the regime dependent evaluation of the RCMs with a focus on the German and Dutch coast. Trends in the occurrence of the regimes in the winter period of 1961 to 2000 show an increase of the regimes with Western and Southwestern wind directions and a decrease of wind events from Eastern directions in the North Sea. The trend is dominated by the strong positive phase of the NAO especially in the months January to March starting in the beginning of the 1980s. Due to the applied method ERA40 and the RCMs do not necessarily show the same regime at each day. The agreement among the RCM

  3. Potential impacts of climate change on the primary production of regional seas: A comparative analysis of five European seas

    NASA Astrophysics Data System (ADS)

    Holt, Jason; Schrum, Corinna; Cannaby, Heather; Daewel, Ute; Allen, Icarus; Artioli, Yuri; Bopp, Laurent; Butenschon, Momme; Fach, Bettina A.; Harle, James; Pushpadas, Dhanya; Salihoglu, Baris; Wakelin, Sarah

    2016-01-01

    Regional seas are potentially highly vulnerable to climate change, yet are the most directly societally important regions of the marine environment. The combination of widely varying conditions of mixing, forcing, geography (coastline and bathymetry) and exposure to the open-ocean makes these seas subject to a wide range of physical processes that mediates how large scale climate change impacts on these seas' ecosystems. In this paper we explore the response of five regional sea areas to potential future climate change, acting via atmospheric, oceanic and terrestrial vectors. These include the Barents Sea, Black Sea, Baltic Sea, North Sea, Celtic Seas, and are contrasted with a region of the Northeast Atlantic. Our aim is to elucidate the controlling dynamical processes and how these vary between and within these seas. We focus on primary production and consider the potential climatic impacts on: long term changes in elemental budgets, seasonal and mesoscale processes that control phytoplankton's exposure to light and nutrients, and briefly direct temperature response. We draw examples from the MEECE FP7 project and five regional model systems each using a common global Earth System Model as forcing. We consider a common analysis approach, and additional sensitivity experiments. Comparing projections for the end of the 21st century with mean present day conditions, these simulations generally show an increase in seasonal and permanent stratification (where present). However, the first order (low- and mid-latitude) effect in the open ocean projections of increased permanent stratification leading to reduced nutrient levels, and so to reduced primary production, is largely absent, except in the NE Atlantic. Even in the two highly stratified, deep water seas we consider (Black and Baltic Seas) the increase in stratification is not seen as a first order control on primary production. Instead, results show a highly heterogeneous picture of positive and negative change

  4. Seismic stratigraphy, Pleistocene climate, and Tertiary sea level changes

    SciTech Connect

    Lowrie, A.

    1985-02-01

    The Quaternary is characterized by 2 climatic signatures: that of the last 800,000 yr, the upper Pleistocene climatic signature (UPCS), and that of the period from 900,000 to 1,800,000 yr ago, the middle Pleistocene climatic signature (MPCS). Glacial cycles within the UPSC are about 100,000 yr long with interglacials of 10,000-12,000 yr duration and a full glacial period of 20,000-30,000 yr. The cycles of the MPSC range from 20,000 to 40,000 yr duration. Interaction between the 3 planetary orbital parameters of eccentricity, tilt, and precession are believed to cause the observed climatic signatures. From DSDP cores, 8 major Miocene hiatuses have been described. There is a roughly equal duration of hiatuses and deposition, with periods ranging from 0.5 to 2 m.y. +/- 0.5 m.y. The deep-ocean hiatuses correlate well with the seismically determined lowered sea levels of P. Vail. The hiatuses are interpreted to be caused by increased activity of ocean-bottom currents, in turn initiated by increased glacial activity. Thus, it is geologically reasonably that within each period of increased glacial activity there are 100,000-yr long UPSC-type cycles. The UPCS cycles have been tentatively identified in seismic data on the Louisiana, east Greenland, and Caribbean shelves and on the Indus Cone. Miocene glacial cycles should be sought in seismic data using innovative data processing techniques.

  5. Arctic sea ice cover in connection with climate change

    NASA Astrophysics Data System (ADS)

    Alekseev, G. V.; Aleksandrov, E. I.; Glok, N. I.; Ivanov, N. E.; Smolyanitsky, V. M.; Kharlanenkova, N. E.; Yulin, A. V.

    2015-12-01

    Recently published studies on key issues in the evolution of Arctic sea ice cover are reviewed and attempts to answer disputable questions are made in the research part of the work. It is shown that climate warming, manifested in an increase in the surface air temperature, and reduction in the ice cover develop with a high degree of agreement in summer. Based on this fact, anomalies of the September ice-cover area have been retrieved from 1900. They show a significant decrease in the 1930-1940s, which is almost twice as low as in 2007-2012. The influence of fluctuations in the flow of warm and salty Atlantic water is noted in variations in the winter maximum of the ice-cover area in the Barents Sea. An accelerated positive trend has been ascertained for the air temperature in late autumn-early winter in 1993-2012 due to an increase in the open water area in late summer. Inherent regularities of the ice-cover-area variability made it possible to develop a prediction of the monthly values of sea-ice extent with a head time from 6 months to 2 years. Their strong correlation with summer air temperature is used to estimate the onset of summer ice clearance in the Arctic.

  6. Can sea urchins beat the heat? Sea urchins, thermal tolerance and climate change.

    PubMed

    Sherman, Elizabeth

    2015-01-01

    The massive die-off of the long-spined sea urchin, Diadema antillarum, a significant reef grazer, in the mid 1980s was followed by phase shifts from coral dominated to macroalgae dominated reefs in the Caribbean. While Diadema populations have recovered in some reefs with concomitant increases in coral cover, the additional threat of increasing temperatures due to global climate change has not been investigated in adult sea urchins. In this study, I measured acute thermal tolerance of D. antillarum and that of a sympatric sea urchin not associated with coral cover, Echinometra lucunter, over winter, spring, and summer, thus exposing them to substantial natural thermal variation. Animals were taken from the wild and placed in laboratory tanks in room temperature water (∼22 °C) that was then heated at 0.16-0.3 °C min(-1) and the righting behavior of individual sea urchins was recorded. I measured both the temperature at which the animal could no longer right itself (T LoR) and the righting time at temperatures below the T LoR. In all seasons, D. antillarum exhibited a higher mean T LoR than E. lucunter. The mean T LoR of each species increased with increasing environmental temperature revealing that both species acclimatize to seasonal changes in temperatures. The righting times of D. antillarum were much shorter than those of E. lucunter. The longer relative spine length of Diadema compared to that of Echinometra may contribute to their shorter righting times, but does not explain their higher T LoR. The thermal safety margin (the difference between the mean collection temperature and the mean T LoR) was between 3.07-3.66 °C for Echinometra and 3.79-5.67 °C for Diadema. While these thermal safety margins exceed present day temperatures, they are modest compared to those of temperate marine invertebrates. If sea temperatures increase more rapidly than can be accommodated by the sea urchins (either by genetic adaptation, phenotypic plasticity, or both), this

  7. Can sea urchins beat the heat? Sea urchins, thermal tolerance and climate change

    PubMed Central

    2015-01-01

    The massive die-off of the long-spined sea urchin, Diadema antillarum, a significant reef grazer, in the mid 1980s was followed by phase shifts from coral dominated to macroalgae dominated reefs in the Caribbean. While Diadema populations have recovered in some reefs with concomitant increases in coral cover, the additional threat of increasing temperatures due to global climate change has not been investigated in adult sea urchins. In this study, I measured acute thermal tolerance of D. antillarum and that of a sympatric sea urchin not associated with coral cover, Echinometra lucunter, over winter, spring, and summer, thus exposing them to substantial natural thermal variation. Animals were taken from the wild and placed in laboratory tanks in room temperature water (∼22 °C) that was then heated at 0.16–0.3 °C min−1 and the righting behavior of individual sea urchins was recorded. I measured both the temperature at which the animal could no longer right itself (TLoR) and the righting time at temperatures below the TLoR. In all seasons, D. antillarum exhibited a higher mean TLoR than E. lucunter. The mean TLoR of each species increased with increasing environmental temperature revealing that both species acclimatize to seasonal changes in temperatures. The righting times of D. antillarum were much shorter than those of E. lucunter. The longer relative spine length of Diadema compared to that of Echinometra may contribute to their shorter righting times, but does not explain their higher TLoR. The thermal safety margin (the difference between the mean collection temperature and the mean TLoR) was between 3.07–3.66 °C for Echinometra and 3.79–5.67 °C for Diadema. While these thermal safety margins exceed present day temperatures, they are modest compared to those of temperate marine invertebrates. If sea temperatures increase more rapidly than can be accommodated by the sea urchins (either by genetic adaptation, phenotypic plasticity, or both), this

  8. Can sea urchins beat the heat? Sea urchins, thermal tolerance and climate change.

    PubMed

    Sherman, Elizabeth

    2015-01-01

    The massive die-off of the long-spined sea urchin, Diadema antillarum, a significant reef grazer, in the mid 1980s was followed by phase shifts from coral dominated to macroalgae dominated reefs in the Caribbean. While Diadema populations have recovered in some reefs with concomitant increases in coral cover, the additional threat of increasing temperatures due to global climate change has not been investigated in adult sea urchins. In this study, I measured acute thermal tolerance of D. antillarum and that of a sympatric sea urchin not associated with coral cover, Echinometra lucunter, over winter, spring, and summer, thus exposing them to substantial natural thermal variation. Animals were taken from the wild and placed in laboratory tanks in room temperature water (∼22 °C) that was then heated at 0.16-0.3 °C min(-1) and the righting behavior of individual sea urchins was recorded. I measured both the temperature at which the animal could no longer right itself (T LoR) and the righting time at temperatures below the T LoR. In all seasons, D. antillarum exhibited a higher mean T LoR than E. lucunter. The mean T LoR of each species increased with increasing environmental temperature revealing that both species acclimatize to seasonal changes in temperatures. The righting times of D. antillarum were much shorter than those of E. lucunter. The longer relative spine length of Diadema compared to that of Echinometra may contribute to their shorter righting times, but does not explain their higher T LoR. The thermal safety margin (the difference between the mean collection temperature and the mean T LoR) was between 3.07-3.66 °C for Echinometra and 3.79-5.67 °C for Diadema. While these thermal safety margins exceed present day temperatures, they are modest compared to those of temperate marine invertebrates. If sea temperatures increase more rapidly than can be accommodated by the sea urchins (either by genetic adaptation, phenotypic plasticity, or both), this

  9. Improved Upper Ocean/Sea Ice Modeling in the GISS GCM for Investigating Climate Change

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This project built on our previous results in which we highlighted the importance of sea ice in overall climate sensitivity by determining that for both warming and cooling climates, when sea ice was not allowed to change, climate sensitivity was reduced by 35-40%. We also modified the Goddard Institute for Space Studies (GISS) 8 deg x lO deg atmospheric General Circulation Model (GCM) to include an upper-ocean/sea-ice model involving the Semtner three-layer ice/snow thermodynamic model, the Price et al. (1986) ocean mixed layer model and a general upper ocean vertical advection/diffusion scheme for maintaining and fluxing properties across the pycnocline. This effort, in addition to improving the sea ice representation in the AGCM, revealed a number of sensitive components of the sea ice/ocean system. For example, the ability to flux heat through the ice/snow properly is critical in order to resolve the surface temperature properly, since small errors in this lead to unrestrained climate drift. The present project, summarized in this report, had as its objectives: (1) introducing a series of sea ice and ocean improvements aimed at overcoming remaining weaknesses in the GCM sea ice/ocean representation, and (2) performing a series of sensitivity experiments designed to evaluate the climate sensitivity of the revised model to both Antarctic and Arctic sea ice, determine the sensitivity of the climate response to initial ice distribution, and investigate the transient response to doubling CO2.

  10. Improved Upper Ocean/Sea Ice Modeling in the GISS GCM for Investigating Climate Change

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This project built on our previous results in which we highlighted the importance of sea ice in overall climate sensitivity by determining that for both warming and cooling climates, when sea ice was not allowed to change, climate sensitivity was reduced by 35-40%. We also modified the GISS 8 deg x lO deg atmospheric GCM to include an upper-ocean/sea-ice model involving the Semtner three-layer ice/snow thermodynamic model, the Price et al. (1986) ocean mixed layer model and a general upper ocean vertical advection/diffusion scheme for maintaining and fluxing properties across the pycnocline. This effort, in addition to improving the sea ice representation in the AGCM, revealed a number of sensitive components of the sea ice/ocean system. For example, the ability to flux heat through the ice/snow properly is critical in order to resolve the surface temperature properly, since small errors in this lead to unrestrained climate drift. The present project, summarized in this report, had as its objectives: (1) introducing a series of sea ice and ocean improvements aimed at overcoming remaining weaknesses in the GCM sea ice/ocean representation, and (2) performing a series of sensitivity experiments designed to evaluate the climate sensitivity of the revised model to both Antarctic and Arctic sea ice, determine the sensitivity of the climate response to initial ice distribution, and investigate the transient response to doubling CO2.

  11. Impact of spatial resolution of ocean models in depicting climate change patterns of the North Sea.

    NASA Astrophysics Data System (ADS)

    Narayan, Nikesh; Klein, Birgit; Mathis, Moritz; Klein, Holger; Mikolajewicz, Uwe

    2016-04-01

    The impact of enhanced spatial resolution of models in simulating large scale climate change has been of interest for the modeling community for quite some time. It has been noticed in previous studies that the pattern of Sea Surface Temperature anomalies are better captured by higher resolution models. Significant changes in simulating sea-ice loss associated with global warming was also noticed when the spatial resolution of climate models were enhanced. Spatial resolution is a particular important issue in climate change scenarios of shelf seas such as the North Sea. The North Sea is strongly influenced by its water mass exchanges with North Atlantic to the west and north and Baltic Sea to east. Furthermore, local forcing and changes in advected water masses significantly affect the thermodynamics and stratification patterns in the North Sea, making it a challenging area to study. Under the newly started RACE2 project we are looking at global simulations of Representative Concentration Pathway (RCP) scenarios 4.5 and 8.5 at lower and higher resolutions, performed using the Max Planck Institute Earth System Model (MPIESM). The model resolution is non uniform and achieves the highest resolution over the European Seas by shifting the model poles over Chicago and Central Europe. In the high resolution run, the grid reaches up to a spatial resolution of up to 4 km in part of the German Bight and close to 20 km in the Northern part of North Sea. The placement of model poles at specific locations enables the global model to obtain higher resolution at regional scales (North Sea), without the inherent complications of open boundary conditions. High and low resolution simulations will be compared to determine differences in spatial and temporal pattern of temperature anomalies, fresh water intrusion from the Baltic Sea to North Sea etc. Also taken into consideration will be the changes in simulating local sea level change and response to basin scale oscillations like NAO.

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

    PubMed

    Drijfhout, Sybren; Gleeson, Emily; Dijkstra, Henk A; Livina, Valerie

    2013-12-01

    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 Ice Age. The event was simulated in the preindustrial control run of a high-resolution climate model, without imposing external perturbations. Initial cooling started with a period of enhanced atmospheric blocking over the eastern subpolar gyre. In response, a southward progression of the sea-ice margin occurred, and the sea-level pressure anomaly was locked to the sea-ice margin through thermal forcing. The cold-core high steered more cold air to the area, reinforcing the sea-ice concentration anomaly east of Greenland. The sea-ice surplus was carried southward by ocean currents around the tip of Greenland. South of 70 °N, sea ice already started melting and the associated freshwater anomaly was carried to the Labrador Sea, shutting off deep convection. There, surface waters were exposed longer to atmospheric cooling and sea surface temperature dropped, causing an even larger thermally forced high above the Labrador Sea. In consequence, east of Greenland, anomalous winds changed from north to south, terminating the event with similar abruptness to its onset. Our results imply that only climate models that possess sufficient resolution to correctly represent atmospheric blocking, in combination with a sensitive sea-ice model, are able to simulate this kind of abrupt climate change.

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

    PubMed

    Drijfhout, Sybren; Gleeson, Emily; Dijkstra, Henk A; Livina, Valerie

    2013-12-01

    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 Ice Age. The event was simulated in the preindustrial control run of a high-resolution climate model, without imposing external perturbations. Initial cooling started with a period of enhanced atmospheric blocking over the eastern subpolar gyre. In response, a southward progression of the sea-ice margin occurred, and the sea-level pressure anomaly was locked to the sea-ice margin through thermal forcing. The cold-core high steered more cold air to the area, reinforcing the sea-ice concentration anomaly east of Greenland. The sea-ice surplus was carried southward by ocean currents around the tip of Greenland. South of 70 °N, sea ice already started melting and the associated freshwater anomaly was carried to the Labrador Sea, shutting off deep convection. There, surface waters were exposed longer to atmospheric cooling and sea surface temperature dropped, causing an even larger thermally forced high above the Labrador Sea. In consequence, east of Greenland, anomalous winds changed from north to south, terminating the event with similar abruptness to its onset. Our results imply that only climate models that possess sufficient resolution to correctly represent atmospheric blocking, in combination with a sensitive sea-ice model, are able to simulate this kind of abrupt climate change. PMID:24248352

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

    PubMed Central

    Drijfhout, Sybren; Gleeson, Emily; Dijkstra, Henk A.; Livina, Valerie

    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 Ice Age. The event was simulated in the preindustrial control run of a high-resolution climate model, without imposing external perturbations. Initial cooling started with a period of enhanced atmospheric blocking over the eastern subpolar gyre. In response, a southward progression of the sea-ice margin occurred, and the sea-level pressure anomaly was locked to the sea-ice margin through thermal forcing. The cold-core high steered more cold air to the area, reinforcing the sea-ice concentration anomaly east of Greenland. The sea-ice surplus was carried southward by ocean currents around the tip of Greenland. South of 70°N, sea ice already started melting and the associated freshwater anomaly was carried to the Labrador Sea, shutting off deep convection. There, surface waters were exposed longer to atmospheric cooling and sea surface temperature dropped, causing an even larger thermally forced high above the Labrador Sea. In consequence, east of Greenland, anomalous winds changed from north to south, terminating the event with similar abruptness to its onset. Our results imply that only climate models that possess sufficient resolution to correctly represent atmospheric blocking, in combination with a sensitive sea-ice model, are able to simulate this kind of abrupt climate change. PMID:24248352

  15. Sea-level rise caused by climate change and its implications for society

    PubMed Central

    MIMURA, Nobuo

    2013-01-01

    Sea-level rise is a major effect of climate change. It has drawn international attention, because higher sea levels in the future would cause serious impacts in various parts of the world. There are questions associated with sea-level rise which science needs to answer. To what extent did climate change contribute to sea-level rise in the past? How much will global mean sea level increase in the future? How serious are the impacts of the anticipated sea-level rise likely to be, and can human society respond to them? This paper aims to answer these questions through a comprehensive review of the relevant literature. First, the present status of observed sea-level rise, analyses of its causes, and future projections are summarized. Then the impacts are examined along with other consequences of climate change, from both global and Japanese perspectives. Finally, responses to adverse impacts will be discussed in order to clarify the implications of the sea-level rise issue for human society. PMID:23883609

  16. Sea-level rise caused by climate change and its implications for society.

    PubMed

    Mimura, Nobuo

    2013-01-01

    Sea-level rise is a major effect of climate change. It has drawn international attention, because higher sea levels in the future would cause serious impacts in various parts of the world. There are questions associated with sea-level rise which science needs to answer. To what extent did climate change contribute to sea-level rise in the past? How much will global mean sea level increase in the future? How serious are the impacts of the anticipated sea-level rise likely to be, and can human society respond to them? This paper aims to answer these questions through a comprehensive review of the relevant literature. First, the present status of observed sea-level rise, analyses of its causes, and future projections are summarized. Then the impacts are examined along with other consequences of climate change, from both global and Japanese perspectives. Finally, responses to adverse impacts will be discussed in order to clarify the implications of the sea-level rise issue for human society.(Communicated by Kiyoshi HORIKAWA, M.J.A.).

  17. Do climate models reproduce complexity of observed sea level changes?

    NASA Astrophysics Data System (ADS)

    Becker, M.; Karpytchev, M.; Marcos, M.; Jevrejeva, S.; Lennartz-Sassinek, S.

    2016-05-01

    The ability of Atmosphere-Ocean General Circulation Models (AOGCMs) to capture the statistical behavior of sea level (SL) fluctuations has been assessed at the local scale. To do so, we have compared scaling behavior of the SL fluctuations simulated in the historical runs of 36 CMIP5 AOGCMs to that in the longest (>100 years) SL records from 23 tides gauges around the globe. The observed SL fluctuations are known to manifest a power law scaling. We have checked if the SL changes simulated in the AOGCM exhibit the same scaling properties and the long-term correlations as observed in the tide gauge records. We find that the majority of AOGCMs overestimates the scaling of SL fluctuations, particularly in the North Atlantic. Consequently, AOGCMs, routinely used to project regional SL rise, may underestimate the part of the externally driven SL rise, in particular the anthropogenic footprint, in the projections for the 21st century.

  18. Using expert opinion to prioritize impacts of climate change on sea turtles' nesting grounds.

    PubMed

    Fuentes, M M P B; Cinner, J E

    2010-12-01

    Managers and conservationists often need to prioritize which impacts from climate change to deal with from a long list of threats. However, data which allows comparison of the relative impact from climatic threats for decision-making is often unavailable. This is the case for the management of sea turtles in the face of climate change. The terrestrial life stages of sea turtles can be negatively impacted by various climatic processes, such as sea level rise, altered cyclonic activity, and increased sand temperatures. However, no study has systematically investigated the relative impact of each of these climatic processes, making it challenging for managers to prioritize their decisions and resources. To address this we offer a systematic method for eliciting expert knowledge to estimate the relative impact of climatic processes on sea turtles' terrestrial reproductive phase. For this we used as an example the world's largest population of green sea turtles and asked 22 scientists and managers to answer a paper based survey with a series of pair-wise comparison matrices that compared the anticipated impacts from each climatic process. Both scientists and managers agreed that increased sand temperature will likely cause the most threat to the reproductive output of the nGBR green turtle population followed by sea level rise, then altered cyclonic activity. The methodology used proved useful to determine the relative impact of the selected climatic processes on sea turtles' reproductive output and provided valuable information for decision-making. Thus, the methodological approach can potentially be applied to other species and ecosystems of management concern. PMID:20702026

  19. Using expert opinion to prioritize impacts of climate change on sea turtles' nesting grounds.

    PubMed

    Fuentes, M M P B; Cinner, J E

    2010-12-01

    Managers and conservationists often need to prioritize which impacts from climate change to deal with from a long list of threats. However, data which allows comparison of the relative impact from climatic threats for decision-making is often unavailable. This is the case for the management of sea turtles in the face of climate change. The terrestrial life stages of sea turtles can be negatively impacted by various climatic processes, such as sea level rise, altered cyclonic activity, and increased sand temperatures. However, no study has systematically investigated the relative impact of each of these climatic processes, making it challenging for managers to prioritize their decisions and resources. To address this we offer a systematic method for eliciting expert knowledge to estimate the relative impact of climatic processes on sea turtles' terrestrial reproductive phase. For this we used as an example the world's largest population of green sea turtles and asked 22 scientists and managers to answer a paper based survey with a series of pair-wise comparison matrices that compared the anticipated impacts from each climatic process. Both scientists and managers agreed that increased sand temperature will likely cause the most threat to the reproductive output of the nGBR green turtle population followed by sea level rise, then altered cyclonic activity. The methodology used proved useful to determine the relative impact of the selected climatic processes on sea turtles' reproductive output and provided valuable information for decision-making. Thus, the methodological approach can potentially be applied to other species and ecosystems of management concern.

  20. Climate change induced decadal variations in hydrodynamic conditions in the Eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Suursaar, U.; Kullas, T.

    2010-12-01

    Climate change manifests in the Baltic Sea region as increasing air and water temperatures, decrease in salinity and in shortening of the ice period. In addition, atmospheric westflow and storminess has intensified, which should also lead to changes in hydrodynamic regime of the sea. The objective of the paper is to study these changes in the practically tideless, fetch-limited nearshore region of West Estonia. The study is based on meteorological and sea level data from the Estonian weather and tide gauge stations, as well as on hydrodynamic modelling experiments with the shallow sea 2D model and wave hindcast for the period 1966-2008. Corrected with locally varying postglacial land uplift rates, the sea level rise according to the Estonian data was 1.5-2.7 mm/year over the period 1842-2009. Steeper than the lobal sea level rise, the rise in winter sea level, and particularly in annual maxima (3.5-11.2 mm/year), could be explained by the local sea level response to the changing regional wind climate. There are site-dependent changes in current patterns and upwelling occurrences. The significant wave heights exhibited some quasiperiodic cycles with the last high stage in 1980-95 and a slightly decreasing overall trend. As a result of northward shifts in cyclone trajectories, annual maximum waves have increased along the windward coasts of West Estonia, but decreased on the northern coast.

  1. Abrupt climate changes for Iceland during the last millennium: Evidence from high resolution sea ice reconstructions

    NASA Astrophysics Data System (ADS)

    Massé, Guillaume; Rowland, Steven J.; Sicre, Marie-Alexandrine; Jacob, Jeremy; Jansen, Eystein; Belt, Simon T.

    2008-05-01

    A high resolution account of Icelandic sea ice over the last millennium has been constructed using a novel proxy based on the presence in sediments of a biomarker (IP 25) produced by sea ice algae. Comparison with historical sea ice records demonstrates a strong correlation between documented sea ice occurrences and the IP 25 proxy. An excellent agreement is also observed between the IP 25 record and a diatom-based sea surface temperature reconstruction obtained from the same core and the Crowley and Lowery Northern Hemisphere temperature reconstruction. Using this approach, we provide new historical sea ice data for periods where records are scarce or absent and evidence for abrupt changes to sea ice and/or climate conditions around Iceland during the Little Ice Age.

  2. Options for managing impacts of climate change on a deep-sea community

    NASA Astrophysics Data System (ADS)

    Thresher, Ronald E.; Guinotte, John M.; Matear, Richard J.; Hobday, Alistair J.

    2015-07-01

    The deep sea hosts some of the world's largest, oldest, and most sensitive ecosystems. Climate change and ocean acidification are likely to have severe implications for many deep-sea ecosystems and communities, but what, if anything, can be done to mitigate these threats is poorly understood. To begin to bridge this gap, we convened a stakeholder workshop to assess and prioritize options for conserving legislatively protected deep-sea coral reefs off southeast Australia that, without management intervention, are likely to be severely degraded within decades as a result of climate change. Seventeen possible options were explored that span biological, engineering and regulatory domains and that differed widely in their perceived costs, benefits, time to implementation, and risks. In the short term, the highest priority identified is the need to urgently locate and protect sites globally that are, or will become, refugia areas for the coral and its associated community as climate change progresses.

  3. Accurately measuring sea level change from space: an ESA climate change initiative for MSL closure budget studies

    NASA Astrophysics Data System (ADS)

    Legeais, JeanFrancois; Benveniste, Jérôme

    2016-07-01

    Sea level is a very sensitive index of climate change and variability. Sea level integrates the ocean warming, mountain glaciers and ice sheet melting. Understanding the sea level variability and changes implies an accurate monitoring of the sea level variable at climate scales, in addition to understanding the ocean variability and the exchanges between ocean, land, cryosphere, and atmosphere. That is why Sea Level is one of the Essential Climate Variables (ECV) selected in the frame of the ESA Climate Change Initiative (CCI) program. It aims at providing long-term monitoring of the sea level ECV with regular updates, as required for climate studies. The program is now in its second phase of 3 year (following phase I during 2011-2013). The objectives are firstly to involve the climate research community, to refine their needs and collect their feedbacks on product quality. And secondly to develop, test and select the best algorithms and standards to generate an updated climate time series and to produce and validate the Sea Level ECV product. This will better answer the climate user needs by improving the quality of the Sea Level products and maintain a sustain service for an up-to-date production. This has led to the production of a first version of the Sea Level ECV which has benefited from yearly extensions and now covers the period 1993-2014. Within phase II, new altimeter standards have been developed and tested in order to reprocess the dataset with the best standards for climate studies. The reprocessed ECV will be released in summer 2016. We will present the main achievements of the ESA CCI Sea Level Project. On the one hand, the major steps required to produce the 22 years climate time series are briefly described: collect and refine the user requirements, development of adapted algorithms for climate applications and specification of the production system. On the other hand, the product characteristics are described as well as the results from product

  4. Arctic Sea Ice Changes, Interactions, and Feedbacks on the Arctic Climate during the Satellite Era

    NASA Astrophysics Data System (ADS)

    Wang, X.; Key, J. R.; Liu, Y.

    2011-12-01

    Of all the components of the Earth climate system, the cryosphere is arguably the least understood even though it is a very important indicator and an effective modulator of regional and global climate change. Changes in sea ice will significantly affect exchanges of momentum, heat, and mass between the ocean and the atmosphere, and have profound socio-economic impacts on transportation, fisheries, hunting, polar animal habitat and more. In the last three decades, the Arctic underwent significant changes in sea ice as part of the accelerated global climate change. With the recently developed One-dimensional Thermodynamic Ice Model (OTIM), sea and lake ice thickness and trends can be reasonably estimated. The OTIM has been extensively validated against submarine and moored upward-looking sonar measurements, meteorological station measurements, and comprehensive numerical model simulations. The Extended AVHRR Polar Pathfinder (APP-x) dataset has 25 climate parameters covering surface, cloud, and sea ice properties as well as surface and top-of-atmosphere radiative fluxes for the period 1982 - 2004 over the Arctic and Antarctic at 25 km resolution. The OTIM has been used with APP-x dataset for Arctic sea ice thickness and volume estimation. Statistical analysis of spatial and temporal distributions and trends in sea ice extent, thickness, and volume over the satellite period has been performed, along with the temporal analysis of first year and multiple year sea ice extent changes. Preliminary results show clear evidence that Arctic sea ice has been experiencing significant changes over the last two decades of the 20th century. The Arctic sea ice has been shrinking unexpectedly fast with the declines in sea ice extent, thickness, and volume, most apparent in the fall season. Moreover, satellites provide an unprecedented opportunity to observe Arctic sea ice and its changes with high spatial and temporal coverage that is making it an ideal data source for mitigating

  5. Impact of climate change on fish population dynamics in the Baltic sea: a dynamical downscaling investigation.

    PubMed

    Mackenzie, Brian R; Meier, H E Markus; Lindegren, Martin; Neuenfeldt, Stefan; Eero, Margit; Blenckner, Thorsten; Tomczak, Maciej T; Niiranen, Susa

    2012-09-01

    Understanding how climate change, exploitation and eutrophication will affect populations and ecosystems of the Baltic Sea can be facilitated with models which realistically combine these forcings into common frameworks. Here, we evaluate sensitivity of fish recruitment and population dynamics to past and future environmental forcings provided by three ocean-biogeochemical models of the Baltic Sea. Modeled temperature explained nearly as much variability in reproductive success of sprat (Sprattus sprattus; Clupeidae) as measured temperatures during 1973-2005, and both the spawner biomass and the temperature have influenced recruitment for at least 50 years. The three Baltic Sea models estimate relatively similar developments (increases) in biomass and fishery yield during twenty-first century climate change (ca. 28 % range among models). However, this uncertainty is exceeded by the one associated with the fish population model, and by the source of global climate data used by regional models. Knowledge of processes and biases could reduce these uncertainties.

  6. Development of sea level rise scenarios for climate change assessments of the Mekong Delta, Vietnam

    USGS Publications Warehouse

    Doyle, Thomas W.; Day, Richard H.; Michot, Thomas C.

    2010-01-01

    Rising sea level poses critical ecological and economical consequences for the low-lying megadeltas of the world where dependent populations and agriculture are at risk. The Mekong Delta of Vietnam is one of many deltas that are especially vulnerable because much of the land surface is below mean sea level and because there is a lack of coastal barrier protection. Food security related to rice and shrimp farming in the Mekong Delta is currently under threat from saltwater intrusion, relative sea level rise, and storm surge potential. Understanding the degree of potential change in sea level under climate change is needed to undertake regional assessments of potential impacts and to formulate adaptation strategies. This report provides constructed time series of potential sea level rise scenarios for the Mekong Delta region by incorporating (1) aspects of observed intra- and inter-annual sea level variability from tide records and (2) projected estimates for different rates of regional subsidence and accelerated eustacy through the year 2100 corresponding with the Intergovernmental Panel on Climate Change (IPCC) climate models and emission scenarios.

  7. Climate program "stone soup": Assessing climate change vulnerabilities in the Aleutian and Bering Sea Islands of Alaska

    NASA Astrophysics Data System (ADS)

    Littell, J. S.; Poe, A.; van Pelt, T.

    2015-12-01

    Climate change is already affecting the Bering Sea and Aleutian Island region of Alaska. Past and present marine research across a broad spectrum of disciplines is shedding light on what sectors of the ecosystem and the human dimension will be most impacted. In a grassroots approach to extend existing research efforts, leveraging recently completed downscaled climate projections for the Bering Sea and Aleutian Islands region, we convened a team of 30 researchers-- with expertise ranging from anthropology to zooplankton to marine mammals-- to assess climate projections in the context of their expertise. This Aleutian-Bering Climate Vulnerability Assessment (ABCVA) began with researchers working in five teams to evaluate the vulnerabilities of key species and ecosystem services relative to projected changes in climate. Each team identified initial vulnerabilities for their focal species or services, and made recommendations for further research and information needs that would help managers and communities better understand the implications of the changing climate in this region. Those draft recommendations were shared during two focused, public sessions held within two hub communities for the Bering and Aleutian region: Unalaska and St. Paul. Qualitative insights about local concerns and observations relative to climate change were collected during these sessions, to be compared to the recommendations being made by the ABCVA team of researchers. Finally, we used a Structured Decision Making process to prioritize the recommendations of participating scientists, and integrate the insights shared during our community sessions. This work brought together residents, stakeholders, scientists, and natural resource managers to collaboratively identify priorities for addressing current and expected future impacts of climate change. Recommendations from this project will be incorporated into future research efforts of the Aleutian and Bering Sea Islands Landscape Conservation

  8. SeaWiFS-2: an ocean color data continuity mission to address climate change

    NASA Astrophysics Data System (ADS)

    Hammann, M. Gregory; Puschell, Jeffery J.

    2009-08-01

    Existing ocean color sensors are near or beyond the end of their mission lives and there will likely be a gap in climate quality Environmental Data Records (EDRs) until planned missions are launched. GeoEye's OrbView2 satellite with the SeaWiFS sensor has provided a 11+ year climatology of global chlorophyll a and other EDRs important for climate change and global warming studies. Upcoming sensors will not provide sufficient accuracy to provide continuity for the EDR time series and global monitoring. A 'stop-gap' mission is required, and we propose using the existing spare SeaWiFS sensor and a dedicated mission.

  9. Influence of the North Atlantic on climate change in the Barents Sea

    NASA Astrophysics Data System (ADS)

    Glok, Natalia; Alekseev, Genrikh; Smirnov, Aleksander; Vyasilova, Anastasia

    2015-04-01

    This study is based on the observations taken from the meteorological archives, satellite and historic visual observations of sea ice, global SST, data of water temperature in the upper layer on the section in the Barents Sea. For processing data was used factor analysis, calculation of correlation matrices with different delay between the Barents Sea and selected areas in North Atlantic. It is shown that the inflow of Atlantic water into the Barents Sea has a major influence on the climate of the region and its changes affect the variations of all climate characteristics. Decadal and interannual changes of air temperature in the Barents Sea are closely related (correlation over 0.8) with temperature of water, coming from the Norwegian Sea. The effect of these changes is seen in the air temperature in the Kara Sea. Atlantic water inflow especially impact on winter sea ice in the Barents Sea. The correlation between the average water temperature at section along the Kola meridian and sea ice extent in the Barents Sea in May reaches values of -0.86. To enhance the predictive capability established dependence, the study was extended to the area of the North Atlantic, where temperature anomalies are formed. In the North Atlantic from the equator to 80 ° N were identified 6 areas where the average annual SST anomalies are associated with SST anomalies and sea ice extent (SIE) in the Barents Sea. Detailed analysis with monthly SST from HadISST for 1951 - 2013 identified two areas with the greatest influence on the Barents Sea. One area is the northern region of the Gulf Stream and other is the equatorial region. The corresponding delays amounted to 26 months and 4-5 years. The relationship between changes AMO index, averaged over August-October, and SIE in the Barents Sea in January is evaluated. Correlation coefficient between them with 3 year delay is -0.54. Implemented study revealed the importance of teleconnection between SST anomalies in the North Atlantic and SST

  10. SEA screening of voluntary climate change plans: A story of non-compliant discretion

    SciTech Connect

    Kørnøv, Lone Wejs, Anja

    2013-07-15

    Screening within Strategic Environmental Assessment (SEA) is the first critical stage involving considerations on whether an assessment is carried out or not. Although legislation and guidance offer practitioners a legal and logical approach to the screening process, it is inevitable that discretionary judgement takes place and will impact on the screening decision. This article examines the results of discretion involved in screening of climate change plans (CCPs) in a Danish context. These years voluntary CCPs are developed as a response to the global and local emergence of both mitigation and adaptation, and the voluntary commitment by the local authorities is an indication of an emerging norm of climate change as an important issue. This article takes its point of departure in the observation that SEA is not undertaken for these voluntary CCPs. The critical analysis of this phenomenon rests upon a documentary study of Danish CCPs, interviews with a lawyer and ministerial key person and informal discussions between researchers, practitioners and lawyers on whether climate change plans are covered by SEA legislation and underlying reasons for the present practice. Based on a critical analysis of mandatory SEA and/or obligation to screen CCPs according to significance criteria, the authors find that 18 out of the 48 CCPs are mandatory to SEA and 9 would require a screening of significance and thereby potentially be followed by a SEA. In practice only one plan was screened and one was environmentally assessed. The legal, democratic and environmental consequences of this SEA practice are critically discussed. Hereunder is the missed opportunity to use the broad environmental scope of SEA to avoid a narrow focus on energy and CO{sub 2} in CCPs, and the question whether this practice in Denmark complies with the EU Directive. -- Highlights: ► It is inevitable that discretionary judgement takes place and will impact on the screening decision. ► The article hereby

  11. Mediterranean Sea response to climate change in an ensemble of twenty first century scenarios

    NASA Astrophysics Data System (ADS)

    Adloff, Fanny; Somot, Samuel; Sevault, Florence; Jordà, Gabriel; Aznar, Roland; Déqué, Michel; Herrmann, Marine; Marcos, Marta; Dubois, Clotilde; Padorno, Elena; Alvarez-Fanjul, Enrique; Gomis, Damià

    2015-11-01

    The Mediterranean climate is expected to become warmer and drier during the twenty-first century. Mediterranean Sea response to climate change could be modulated by the choice of the socio-economic scenario as well as the choice of the boundary conditions mainly the Atlantic hydrography, the river runoff and the atmospheric fluxes. To assess and quantify the sensitivity of the Mediterranean Sea to the twenty-first century climate change, a set of numerical experiments was carried out with the regional ocean model NEMOMED8 set up for the Mediterranean Sea. The model is forced by air-sea fluxes derived from the regional climate model ARPEGE-Climate at a 50-km horizontal resolution. Historical simulations representing the climate of the period 1961-2000 were run to obtain a reference state. From this baseline, various sensitivity experiments were performed for the period 2001-2099, following different socio-economic scenarios based on the Special Report on Emissions Scenarios. For the A2 scenario, the main three boundary forcings (river runoff, near-Atlantic water hydrography and air-sea fluxes) were changed one by one to better identify the role of each forcing in the way the ocean responds to climate change. In two additional simulations (A1B, B1), the scenario is changed, allowing to quantify the socio-economic uncertainty. Our 6-member scenario simulations display a warming and saltening of the Mediterranean. For the 2070-2099 period compared to 1961-1990, the sea surface temperature anomalies range from +1.73 to +2.97 °C and the SSS anomalies spread from +0.48 to +0.89. In most of the cases, we found that the future Mediterranean thermohaline circulation (MTHC) tends to reach a situation similar to the eastern Mediterranean Transient. However, this response is varying depending on the chosen boundary conditions and socio-economic scenarios. Our numerical experiments suggest that the choice of the near-Atlantic surface water evolution, which is very uncertain in

  12. Contribution of Regional Climate Drivers to Future Winter Sea-Level Changes in the Baltic Sea Estimated by Statistical Methods and Simulations of Climate Models

    NASA Astrophysics Data System (ADS)

    Hünicke, B.; Zorita, E.

    2008-12-01

    A statistical downscaling approach is applied to the output of different global climate model simulations driven by SRES A2 future scenarios of greenhouse gas concentrations to estimate the contribution of changes in the atmospheric circulation and in precipitation to regional future winter sea-level changes. The method is based on observed statistical relationships between Sea level as predictand and large-scale climate fields as predictors. The approach is applied to the Baltic Sea as it is one of the largest brackish seas in the world and a clear example for a complex coupled ocean-atmosphere land system with a complex coastline and bathymetry. Recent studies indicated that Baltic Sea level variations on decadal and longer time scales are strongly influenced by atmospheric forcings, but the influence of different large-scale forcing factors on sea level vary geographically. While the decadal sea level variations in the northern and eastern Baltic gauges are strongly influenced by the atmospheric circulation, the decadal variations in the southern Baltic Sea can be (statistically) better explained by area-averaged precipitation. The results indicate that future trends in sea-level rise caused by these forcing are larger than the past variability. Using sea level pressure as predictor for the central and eastern Baltic Sea level stations, three climate models lead to 21st century future trends in the range of the order of 1 to 2 mm/year. Using precipitation as predictor for the stations in the Southern Baltic Coast all five models lead to significant trends with a range of the order of 0.4 mm/year. These numbers are smaller, but of the order of magnitude as the predicted future global sea level rise. Nevertheless, these estimations comprise only a partial contribution of selected large-scale regional predictors and an estimation of the total regional sea-level rise has to consider other regional factors such as the isostatic contribution to relative sea

  13. Transition process of abrupt climate change based on global sea surface temperature over the past century

    NASA Astrophysics Data System (ADS)

    Yan, Pengcheng; Hou, Wei; Feng, Guolin

    2016-05-01

    A new detection method has been proposed to study the transition process of abrupt climate change. With this method, the climate system transiting from one stable state to another can be verified clearly. By applying this method to the global sea surface temperature over the past century, several climate changes and their processes are detected, including the start state (moment), persist time, and end state (moment). According to the spatial distribution, the locations of climate changes mainly have occurred in the Indian Ocean and western Pacific before the middle twentieth century, in the 1970s in the equatorial middle-eastern Pacific, and in the middle and southern Pacific since the end of the twentieth century. In addition, the quantitative relationship between the transition process parameters is verified in theory and practice: (1) the relationship between the rate and stability parameters is linear, and (2) the relationship between the rate and change amplitude parameters is quadratic.

  14. Arctic sea ice and climate change--will the ice disappear in this century?

    PubMed

    Johannessen, O M; Miles, M W

    2000-01-01

    A consensus among climate change prediction scenarios using coupled ocean-climate general circulation models (GCMs) is enhanced warming in the Arctic. This suggests that changes in the Arctic sea ice cover may provide early indications of global warming. Observational evidence of substantial changes in the ice cover has been found recently using data from satellites and submarines. Satellite-borne microwave sensor data analyses have established a 3% per decade decrease in the spatial extent of the Arctic ice cover in the past 20 years. Moreover, a 7% per decade decrease in thicker, multi-year (perennial) ice pack has been revealed. This apparent transformation is corroborated by independent data that indicate substantial decreases in the average ice thickness from 3.1 to 1.8 m from the 1950s/1970s to the mid 1990s, averaging about 4 cm per year. It remains uncertain whether these observed changes are manifestations of global warming or are the result of anomalous atmospheric circulation--or both. However, if the recent trends continue, the Arctic sea ice cover could disappear this century, at least in summer, with important consequences for the regional and global ocean-climate system. This article synthesizes recent variability and trends in Arctic sea ice in the perspective of global climate change, and discusses their potential ramifications. PMID:11077477

  15. Deep-Sea Biodiversity Response to Abrupt Deglacial and Holocene Climate Changes

    NASA Astrophysics Data System (ADS)

    Yasuhara, M.

    2014-12-01

    High-resolution records of microfossil assemblages from deep-sea sediment cores covering the last 20,000 years in the North Atlantic Ocean were investigated to understand biotic responses to abrupt climate changes over decadal-centennial timescales. The results show pervasive control of deep-sea benthic species diversity by rapidly changing climate. Species diversity rapidly increased during abrupt stadial events during the last deglacial and the Holocene interglacial periods. These included the well-known Heinrich 1, the Younger Dryas, and the 8.2 ka events when the strength of Atlantic Meridional Overturning Circulation (AMOC) decreased. In addition, there is evidence for quasi-cyclic changes in biodiversity at a ~1500-year periodicity. Statistical analyses revealed that AMOC-driven bottom-water-temperature variability is a primary influence on deep-sea biodiversity. Our results may portend pervasive, synchronous and sudden ecosystem responses to human-induced changes to climate and ocean circulation in this century. Exceptionally highly resolved fossil records help us to understand past, present and future ecosystem responses to climate changes by bridging the gap between biological and palaeontological time-scales.

  16. Arctic sea ice and climate change--will the ice disappear in this century?

    PubMed

    Johannessen, O M; Miles, M W

    2000-01-01

    A consensus among climate change prediction scenarios using coupled ocean-climate general circulation models (GCMs) is enhanced warming in the Arctic. This suggests that changes in the Arctic sea ice cover may provide early indications of global warming. Observational evidence of substantial changes in the ice cover has been found recently using data from satellites and submarines. Satellite-borne microwave sensor data analyses have established a 3% per decade decrease in the spatial extent of the Arctic ice cover in the past 20 years. Moreover, a 7% per decade decrease in thicker, multi-year (perennial) ice pack has been revealed. This apparent transformation is corroborated by independent data that indicate substantial decreases in the average ice thickness from 3.1 to 1.8 m from the 1950s/1970s to the mid 1990s, averaging about 4 cm per year. It remains uncertain whether these observed changes are manifestations of global warming or are the result of anomalous atmospheric circulation--or both. However, if the recent trends continue, the Arctic sea ice cover could disappear this century, at least in summer, with important consequences for the regional and global ocean-climate system. This article synthesizes recent variability and trends in Arctic sea ice in the perspective of global climate change, and discusses their potential ramifications.

  17. Arctic sea ice area in CMIP3 and CMIP5 climate model ensembles - variability and change

    NASA Astrophysics Data System (ADS)

    Semenov, V. A.; Martin, T.; Behrens, L. K.; Latif, M.

    2015-02-01

    The shrinking Arctic sea ice cover observed during the last decades is probably the clearest manifestation of ongoing climate change. While climate models in general reproduce the sea ice retreat in the Arctic during the 20th century and simulate further sea ice area loss during the 21st century in response to anthropogenic forcing, the models suffer from large biases and the model results exhibit considerable spread. The last generation of climate models from World Climate Research Programme Coupled Model Intercomparison Project Phase 5 (CMIP5), when compared to the previous CMIP3 model ensemble and considering the whole Arctic, were found to be more consistent with the observed changes in sea ice extent during the recent decades. Some CMIP5 models project strongly accelerated (non-linear) sea ice loss during the first half of the 21st century. Here, complementary to previous studies, we compare results from CMIP3 and CMIP5 with respect to regional Arctic sea ice change. We focus on September and March sea ice. Sea ice area (SIA) variability, sea ice concentration (SIC) variability, and characteristics of the SIA seasonal cycle and interannual variability have been analysed for the whole Arctic, termed Entire Arctic, Central Arctic and Barents Sea. Further, the sensitivity of SIA changes to changes in Northern Hemisphere (NH) averaged temperature is investigated and several important dynamical links between SIA and natural climate variability involving the Atlantic Meridional Overturning Circulation (AMOC), North Atlantic Oscillation (NAO) and sea level pressure gradient (SLPG) in the western Barents Sea opening serving as an index of oceanic inflow to the Barents Sea are studied. The CMIP3 and CMIP5 models not only simulate a coherent decline of the Arctic SIA but also depict consistent changes in the SIA seasonal cycle and in the aforementioned dynamical links. The spatial patterns of SIC variability improve in the CMIP5 ensemble, particularly in summer. Both

  18. Climate change scenarios and the effect of sea-level rise for Estonia

    NASA Astrophysics Data System (ADS)

    Kont, Are; Jaagus, Jaak; Aunap, Raivo

    2003-03-01

    Climate warming due to the enhanced greenhouse effect is expected to have a significant impact on natural environment and human activity in high latitudes. Mostly, it should have a positive effect on human activity. The main threats in Estonia that could be connected with sea-level rise are the flooding of coastal areas, erosion of sandy beaches and the destruction of harbour constructions. Possible climate change and its negative impacts in the coastal regions of Estonia are estimated in this paper. Climate change scenarios for Estonia were generated using a Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) and a regional climate change database—SCENanario GENerator (SCENGEN). Three alternative emission scenarios were combined with data from 14 general circulation model experiments. Climate change scenarios for the year 2100 indicate a significant increase in air temperature (by 2.3-4.5 °C) and precipitation (by 5-30%) in Estonia. The highest increase is expected to take place during winter and the lowest increase in summer. Due to a long coastline (3794 km) and extensive low-lying coastal areas, global climate change through sea-level rise will strongly affect the territory of Estonia. A number of valuable natural ecosystems will be in danger. These include both marine and terrestrial systems containing rare plant communities and suitable breeding places for birds. Most sandy beaches high in recreational value will disappear. However, isostatic land uplift and the location of coastal settlements at a distance from the present coastline reduce the rate of risk. Seven case study areas characterising all the shore types of Estonia have been selected for sea-level rise vulnerability and adaptation assessment. Results and estimates of vulnerability to 1.0-m sea-level rise by 2100 are presented in this paper. This is the maximum scenario according to which the actually estimated relative sea-level rise would vary from 0.9 m (SW Estonia) to 0

  19. Temperature tracking by North Sea benthic invertebrates in response to climate change.

    PubMed

    Hiddink, Jan G; Burrows, Michael T; García Molinos, Jorge

    2015-01-01

    Climate change is a major threat to biodiversity and distributions shifts are one of the most significant threats to global warming, but the extent to which these shifts keep pace with a changing climate is yet uncertain. Understanding the factors governing range shifts is crucial for conservation management to anticipate patterns of biodiversity distribution under future anthropogenic climate change. Soft-sediment invertebrates are a key faunal group because of their role in marine biogeochemistry and as a food source for commercial fish species. However, little information exists on their response to climate change. Here, we evaluate changes in the distribution of 65 North Sea benthic invertebrate species between 1986 and 2000 by examining their geographic, bathymetric and thermal niche shifts and test whether species are tracking their thermal niche as defined by minimum, mean or maximum sea bottom (SBT) and surface (SST) temperatures. Temperatures increased in the whole North Sea with many benthic invertebrates showing north-westerly range shifts (leading/trailing edges as well as distribution centroids) and deepening. Nevertheless, distribution shifts for most species (3.8-7.3 km yr(-1) interquantile range) lagged behind shifts in both SBT and SST (mean 8.1 km yr(-1)), resulting in many species experiencing increasing temperatures. The velocity of climate change (VoCC) of mean SST accurately predicted both the direction and magnitude of distribution centroid shifts, while maximum SST did the same for contraction of the trailing edge. The VoCC of SBT was not a good predictor of range shifts. No good predictor of expansions of the leading edge was found. Our results show that invertebrates need to shift at different rates and directions to track the climate velocities of different temperature measures, and are therefore lagging behind most temperature measures. If these species cannot withstand a change in thermal habitat, this could ultimately lead to a drop in

  20. Predictions of extreme precipitation and sea-level rise under climate change.

    PubMed

    Senior, C A; Jones, R G; Lowe, J A; Durman, C F; Hudson, D

    2002-07-15

    Two aspects of global climate change are particularly relevant to river and coastal flooding: changes in extreme precipitation and changes in sea level. In this paper we summarize the relevant findings of the IPCC Third Assessment Report and illustrate some of the common results found by the current generation of coupled atmosphere-ocean general circulation models (AOGCMs), using the Hadley Centre models. Projections of changes in extreme precipitation, sea-level rise and storm surges affecting the UK will be shown from the Hadley Centre regional models and the Proudman Oceanographic Laboratory storm-surge model. A common finding from AOGCMs is that in a warmer climate the intensity of precipitation will increase due to a more intense hydrological cycle. This leads to reduced return periods (i.e. more frequent occurrences) of extreme precipitation in many locations. The Hadley Centre regional model simulates reduced return periods of extreme precipitation in a number of flood-sensitive areas of the UK. In addition, simulated changes in storminess and a rise in average sea level around the UK lead to reduced return periods of extreme high coastal water events. The confidence in all these results is limited by poor spatial resolution in global coupled models and by uncertainties in the physical processes in both global and regional models, and is specific to the climate change scenario used. PMID:12804251

  1. Predictions of extreme precipitation and sea-level rise under climate change.

    PubMed

    Senior, C A; Jones, R G; Lowe, J A; Durman, C F; Hudson, D

    2002-07-15

    Two aspects of global climate change are particularly relevant to river and coastal flooding: changes in extreme precipitation and changes in sea level. In this paper we summarize the relevant findings of the IPCC Third Assessment Report and illustrate some of the common results found by the current generation of coupled atmosphere-ocean general circulation models (AOGCMs), using the Hadley Centre models. Projections of changes in extreme precipitation, sea-level rise and storm surges affecting the UK will be shown from the Hadley Centre regional models and the Proudman Oceanographic Laboratory storm-surge model. A common finding from AOGCMs is that in a warmer climate the intensity of precipitation will increase due to a more intense hydrological cycle. This leads to reduced return periods (i.e. more frequent occurrences) of extreme precipitation in many locations. The Hadley Centre regional model simulates reduced return periods of extreme precipitation in a number of flood-sensitive areas of the UK. In addition, simulated changes in storminess and a rise in average sea level around the UK lead to reduced return periods of extreme high coastal water events. The confidence in all these results is limited by poor spatial resolution in global coupled models and by uncertainties in the physical processes in both global and regional models, and is specific to the climate change scenario used.

  2. Testing massive Arctic sea ice export as a trigger for abrupt climate change

    NASA Astrophysics Data System (ADS)

    Coletti, Anthony; Condron, Alan; Bradley, Raymond

    2014-05-01

    The discharge of freshwater from glacial lakes to the North Atlantic is repeatedly cited as the main trigger for abrupt centennial to millennial length climate change during the last deglaciation. Broecker et al., (1989) was a proponent of this idea suggesting that abrupt re-routing of pro-glacial lake freshwater to the North Atlantic through the St. Lawrence Valley weakened the strength of the AMOC. Yet, evidence for this is lacking, freshwater estimates in these lakes are relatively small and flood durations are rather short (<5 years), suggesting that floods may not have been the only mechanism driving these climate shifts. Using sophisticated ocean modeling, it has been shown that the release of freshwater originating from the Arctic is more effective at weakening the AMOC compared to freshwater released further south. Here we investigate whether the break-up and mobilization of thick Arctic sea-ice would have supplied enough freshwater to the Nordic Seas to sufficiently cause dampening of the AMOC and hinder NADW formation in the sub-polar North Atlantic. We use numerical climate models to assess 1) the maximum thickness of sea ice that can be formed during glacial periods and the volume of freshwater in the ice, 2) the mechanism which caused the collapse and mobilization of arctic sea-ice into the North Atlantic and 3) the impact of melting sea-ice on global ocean circulation. This hypothesis focuses on the potential impacts of sea-ice as a forcing mechanism for abrupt climate change events on geologic time scales.

  3. Influence of climate change and trophic coupling across four trophic levels in the Celtic Sea.

    PubMed

    Lauria, Valentina; Attrill, Martin J; Pinnegar, John K; Brown, Andrew; Edwards, Martin; Votier, Stephen C

    2012-01-01

    Climate change has had profound effects upon marine ecosystems, impacting across all trophic levels from plankton to apex predators. Determining the impacts of climate change on marine ecosystems requires understanding the direct effects on all trophic levels as well as indirect effects mediated by trophic coupling. The aim of this study was to investigate the effects of climate change on the pelagic food web in the Celtic Sea, a productive shelf region in the Northeast Atlantic. Using long-term data, we examined possible direct and indirect 'bottom-up' climate effects across four trophic levels: phytoplankton, zooplankton, mid-trophic level fish and seabirds. During the period 1986-2007, although there was no temporal trend in the North Atlantic Oscillation index (NAO), the decadal mean Sea Surface Temperature (SST) in the Celtic Sea increased by 0.66 ± 0.02 °C. Despite this, there was only a weak signal of climate change in the Celtic Sea food web. Changes in plankton community structure were found, however this was not related to SST or NAO. A negative relationship occurred between herring abundance (0- and 1-group) and spring SST (0-group: p = 0.02, slope = -0.305 ± 0.125; 1-group: p = 0.04, slope = -0.410 ± 0.193). Seabird demographics showed complex species-specific responses. There was evidence of direct effects of spring NAO (on black-legged kittiwake population growth rate: p = 0.03, slope = 0.0314 ± 0.014) as well as indirect bottom-up effects of lagged spring SST (on razorbill breeding success: p = 0.01, slope = -0.144 ± 0.05). Negative relationships between breeding success and population growth rate of razorbills and common guillemots may be explained by interactions between mid-trophic level fish. Our findings show that the impacts of climate change on the Celtic Sea ecosystem is not as marked as in nearby regions (e.g. the North Sea), emphasizing the need for more research at regional scales.

  4. Response of air-sea carbon fluxes and climate to orbital forcing changes in the Community Climate System Model

    NASA Astrophysics Data System (ADS)

    Jochum, M.; Peacock, S.; Moore, K.; Lindsay, K.

    2010-07-01

    A global general circulation model coupled to an ocean ecosystem model is used to quantify the response of carbon fluxes and climate to changes in orbital forcing. Compared to the present-day simulation, the simulation with the Earth's orbital parameters from 115,000 years ago features significantly cooler northern high latitudes but only moderately cooler southern high latitudes. This asymmetry is explained by a 30% reduction of the strength of the Atlantic Meridional Overturning Circulation that is caused by an increased Arctic sea ice export and a resulting freshening of the North Atlantic. The strong northern high-latitude cooling and the direct insolation induced tropical warming lead to global shifts in precipitation and winds to the order of 10%-20%. These climate shifts lead to regional differences in air-sea carbon fluxes of the same order. However, the differences in global net air-sea carbon fluxes are small, which is due to several effects, two of which stand out: first, colder sea surface temperature leads to a more effective solubility pump but also to increased sea ice concentration which blocks air-sea exchange, and second, the weakening of Southern Ocean winds that is predicted by some idealized studies occurs only in part of the basin, and is compensated by stronger winds in other parts.

  5. Does Change in the Arctic Sea Ice Indicate Climate Change? A Lesson Using Geospatial Technology

    ERIC Educational Resources Information Center

    Bock, Judith K.

    2011-01-01

    The Arctic sea ice has not since melted to the 2007 extent, but annual summer melt extents do continue to be less than the decadal average. Climate fluctuations are well documented by geologic records. Averages are usually based on a minimum of 10 years of averaged data. It is typical for fluctuations to occur from year to year and season to…

  6. Modelling climate change effects on benthos: Distributional shifts in the North Sea from 2001 to 2099

    NASA Astrophysics Data System (ADS)

    Weinert, Michael; Mathis, Moritz; Kröncke, Ingrid; Neumann, Hermann; Pohlmann, Thomas; Reiss, Henning

    2016-06-01

    In the marine realm, climate change can affect a variety of physico-chemical properties with wide-ranging biological effects, but the knowledge of how climate change affects benthic distributions is limited and mainly restricted to coastal environments. To project the response of benthic species of a shelf sea (North Sea) to the expected climate change, the distributions of 75 marine benthic species were modelled and the spatial changes in distribution were projected for 2099 based on modelled bottom temperature and salinity changes using the IPCC scenario A1B. Mean bottom temperature was projected to increase between 0.15 and 5.4 °C, while mean bottom salinity was projected to moderately increase by 1.7. The spatial changes in species distribution were modelled with Maxent and the direction and extent of these changes were assessed. The results showed a latitudinal northward shift for 64% of the species (maximum 109 km; brittle star Ophiothrix fragilis) and a southward shift for 36% (maximum 101 km; hermit crab Pagurus prideaux and the associated cloak anemone Adamsia carciniopados; 105 km). The relatively low rates of distributional shifts compared to fish or plankton species were probably influenced by the regional topography. The environmental gradients in the central North Sea along the 50 m depth contour might act as a 'barrier', possibly resulting in a compression of distribution range and hampering further shifts to the north. For 49 species this resulted in a habitat loss up to 100%, while only 11 species could benefit from the warming in terms of habitat gain. Particularly the benthic communities of the southern North Sea, where the strongest temperature increase was projected, would be strongly affected by the distributional changes, since key species showed northward shifts and high rates of habitat loss, with potential ramifications for the functioning of the ecosystem.

  7. Climate change effects on a miniature ocean: the highly diverse, highly impacted Mediterranean Sea.

    PubMed

    Lejeusne, Christophe; Chevaldonné, Pierre; Pergent-Martini, Christine; Boudouresque, Charles F; Pérez, Thierry

    2010-04-01

    Little doubt is left that climate change is underway, strongly affecting the Earth's biodiversity. Some of the greatest challenges ahead concern the marine realm, but it is unclear to what extent changes will affect marine ecosystems. The Mediterranean Sea could give us some of the answers. Data recovered from its shores and depths have shown that sea temperatures are steadily increasing, extreme climatic events and related disease outbreaks are becoming more frequent, faunas are shifting, and invasive species are spreading. This miniature ocean can serve as a giant mesocosm of the world's oceans, with various sources of disturbances interacting synergistically and therefore providing an insight into a major unknown: how resilient are marine ecosystems, and how will their current functioning be modified?

  8. Satellite Observation of Large Scale Changes in Climate and Land Use in the Caspian Sea Basin

    NASA Astrophysics Data System (ADS)

    Saatchi, S.; Nouri, A.; Asefi, S.; Shiklomanov, A.; Entekhabi, D.; Mohammadi, S.; Hedjazi, B.

    2012-04-01

    The Caspian Sea Basin (catchments) area occupies the vast European and Asian territory between approx. 330-580 N latitude and 300-620 E longitude. In comparison with other world great natural lakes, the Caspian Sea ranks first in watershed area (3660,000 km2) and also in a total annual rivers runoff (340 km3/year - long-term average value). The Caspian is a closed basin with the largest landlocked water body in the world in its center. As a result, the water and biogeochemical cycles over the sea and surrounding lands are intimately linked. Any changes in the hydrologic regime over land and any major shifts in land use and land ecosystem health will directly impact the overall water and energy cycle of the basin, as well as the water quality and aquatic biology of the Sea. The basin being a closed system, it can also exhibit feedback processes that reinforce excursions from normal and lead to large impacts on the surrounding regions. In this paper, we present results of the analysis of climate and vegetation observations over the past 30 years over the Caspian Sea Basin to document the changes of climate, and land use, the regional vegetation response. We focus our analysis using data from AVHRR, MODIS, QSCAT, and TRMM. The results indicate that the region has gone through major changes in land use accompanied by anomalies of temperature and rainfall that in turn has suppressed the vegetation cover and phenology. The results are corroborated by data from socio-economic changes in the region and ground observation of climate and vegetation.

  9. Climate change in the Baltic sea region: a cross-country analysis of institutional stakeholder perceptions.

    PubMed

    Piwowarczyk, Joanna; Hansson, Anders; Hjerpe, Mattias; Chubarenko, Boris; Karmanov, Konstantin

    2012-09-01

    Before climate change is considered in long-term coastal management, it is necessary to investigate how institutional stakeholders in coastal management conceptualize climate change, as their awareness will ultimately affect their actions. Using questionnaires in eight Baltic Sea riparian countries, this study examines environmental managers' awareness of climate change. Our results indicate that problems related to global warming are deemed secondary to short-term social and economic issues. Respondents agree that problems caused by global warming will become increasingly important, but pay little attention to adaptation and mitigation strategies. Current environmental problems are expected to continue to be urgent in the future. We conclude that an apparent gap exists between decision making, public concerns, and scientific consensus, resulting in a situation in which the latest evidence rarely influences commonly held opinions. PMID:22926886

  10. Climate Change

    MedlinePlus

    Climate is the average weather in a place over a period of time. Climate change is major change in temperature, rainfall, snow, ... by natural factors or by human activities. Today climate changes are occurring at an increasingly rapid rate. ...

  11. Future increase in harmful algal blooms in the North Sea due to climate change.

    PubMed

    Peperzak, L

    2005-01-01

    In temperate seas such as the North Sea harmful (toxic) algal blooms will probably increase as a result of climate change. This conclusion was reached after investigating the projected effect of climate change for the year 2100 in Dutch coastal waters (4 degrees C temperature rise and increased water column stratification) on the growth rates of six harmful and two non-harmful phytoplankton species. Micro algae form the basis of the marine food chain. However, toxin-producing species may seriously disrupt the food web and lead to fish kills and human intoxication. Two species with estimated doubled growth rates in 2100, F. japonica and C. antiqua, entered Europe via ship's ballast water or shellfish imports. This stresses the need to legally regulate such invasion routes in order to prevent the import of novel species. Future toxic phytoplankton blooms may further devaluate ecosystem deliverables such as fish production or recreational use. This devaluation can be estimated by monetary value assessments that are needed in cost-benefit analyses for policy guidance. The lack of understanding of future climate, ecosystem functioning and its response to climate change calls for a scientific effort to improve our knowledge on present day coastal ecosystem functioning and its resilience. PMID:15918356

  12. Modeling the impact of changes in Atlantic sea surface temperature on the climate of West Africa

    NASA Astrophysics Data System (ADS)

    Adeniyi, Mojisola O.

    2016-08-01

    This study assesses the impacts of warming/cooling of the Atlantic sea surface temperature (SST) on the climate of West Africa using Version 4.4 of Regional Climate Model (RegCM4.4) of International Center for Theoretical Physics, Trieste, Italy. The 1-2 K cooling and warming of the Atlantic SST both result in tripole temperature and precipitation change structure, having a northwest-southeast orientation over West Africa. Findings reveal that the responses of precipitation and temperature to the Atlantic SST cooling are opposite to those for the Atlantic SST warming and these responses intensify with increased warming/cooling of the Atlantic SST. The structure of the change in climate is attributed to the response of atmospheric/soil moisture gradient and orientation of orography in West Africa.

  13. Climate-mediated changes in zooplankton community structure for the eastern Bering Sea

    NASA Astrophysics Data System (ADS)

    Eisner, Lisa B.; Napp, Jeffrey M.; Mier, Kathryn L.; Pinchuk, Alexei I.; Andrews, Alexander G.

    2014-11-01

    Zooplankton are critical to energy transfer between higher and lower trophic levels in the eastern Bering Sea ecosystem. Previous studies from the southeastern Bering Sea shelf documented substantial differences in zooplankton taxa in the Middle and Inner Shelf Domains between warm and cold years. Our investigation expands this analysis into the northern Bering Sea and the south Outer Domain, looking at zooplankton community structure during a period of climate-mediated, large-scale change. Elevated air temperatures in the early 2000s resulted in regional warming and low sea-ice extent in the southern shelf whereas the late 2000s were characterized by cold winters, extensive spring sea ice, and a well-developed pool of cold water over the entire Middle Domain. The abundance of large zooplankton taxa such as Calanus spp. (C. marshallae and C. glacialis), and Parasagitta elegans, increased from warm to cold periods, while the abundance of gelatinous zooplankton (Cnidaria) and small taxa decreased. Biomass followed the same trends as abundance, except that the biomass of small taxa in the southeastern Bering Sea remained constant due to changes in abundance of small copepod taxa (increases in Acartia spp. and Pseudocalanus spp. and decreases in Oithona spp.). Statistically significant changes in zooplankton community structure and individual species were greatest in the Middle Domain, but were evident in all shelf domains, and in both the northern and southern portions of the eastern shelf. Changes in community structure did not occur abruptly during the transition from warm to cold, but seemed to begin gradually and build as the influence of the sea ice and cold water temperatures persisted. The change occurred one year earlier in the northern than the southern Middle Shelf. These and previous observations demonstrate that lower trophic levels within the eastern Bering Sea respond to climate-mediated changes on a variety of time scales, including those shorter than

  14. Central Asian sand seas climate change as inferred from OSL dating

    NASA Astrophysics Data System (ADS)

    Maman, Shimrit; Tsoar, Haim; Blumberg, Dan; Porat, Naomi

    2014-05-01

    Luminescence dating techniques have become more accessible, widespread, more accurate and support studies of climate change. Optically stimulated luminescence (OSL) is used to determine the time elapsed since quartz grains were last exposed to sunlight, before they were buried and the dune stabilized. Many sand seas have been dated extensively by luminescence, e.g., the Kalahari, Namib the Australian linear dunes and the northwestern Negev dune field, Israel. However, no ages were published so far from the central Asian sand seas. The lack of dune stratigraphy and numerical ages precluded any reliable assessment of the paleoclimatic significance of dunes in central Asia. Central Asian Sand seas (ergs) have accumulated in the Turan basin, north-west of the Hindu Kush range, and span from south Turkmenistan to the Syr-Darya River in Kazakhstan. These ergs are dissected by the Amu-Darya River; to its north lies the Kyzylkum (red sands) and to its south lies the Karakum (black sands). Combined, they form one of the largest sand seas in the world. This area is understudied, and little information has been published regarding the sands stabilization processes and deposition ages. In this study, OSL ages for the Karakum and Kyzylkum sands are presented and analysis of the implications of these results is provided. Optical dates obtained in this study are used to study the effects climatic changes had on the mobility and stability of the central Asian sand seas. Optically stimulated luminescence ages derived from the upper meter of the interdune of 14 exposed sections from both ergs, indicate extensive sand and dune stabilization during the mid-Holocene. This stabilization is understood to reflect a transition to a warmer, wetter, and less windy climate that generally persisted until today. The OSL ages, coupled with a compilation of regional paleoclimatic data, corroborate and reinforce the previously proposed Mid-Holocene Liavliakan phase, known to reflect a warmer

  15. Glacial to Interglacial Climate and Sea Level Changes Recorded in Submerged Speleothems, Argentarola, Italy

    NASA Astrophysics Data System (ADS)

    Folz-Donahue, K.; Dutton, A.; Antonioli, F.; Richards, D. A.; Nita, D. C.; Lambeck, K.

    2014-12-01

    Direct records of Quaternary sea level change can provide insight on the timing and nature of ice sheet retreat during glacial terminations. Such records are generally rare, particularly prior to the last deglaciation, due in part to the difficulty of recovering material from sites that have been submerged by subsequent sea-level rise. A suite of stalagmites recovered from a submerged cave on Argentarola Island in the Tyrrhenian Sea contains hiatuses that were formed when the cave became submerged by seawater. These hiatuses are remarkable due to the presence of calcite tubes secreted by serpulid worms, providing direct evidence of marine inundation. As sea level drops during the following glacial inception, the cave is drained and dense spelean calcite encases the serpulid worm tubes, forming alternating layers of spelean and serpulid calcite. U-Th dates of spelean calcite directly above and below these serpulid layers has previously been used to constrain timing and amplitude of sea level highstands in the Mediterranean. Stable isotope records from the same cave have also been used to indicate increased precipitation across the Mediterranean during Sapropel 6 (175 ka). Here we present U-Th dates and stable isotope records for three Argentarola stalagmites. These specimens were recovered from -22, -18, and -14 m relative to present sea level (rpsl), and complement previously published data for Argentarola stalagmites at -21, -18.5, and -18 m rpsl. The timing and elevation of spelean calcite directly above and below serpulid tube layers provide rare insight on rates of sea-level change between -14 and -22 m during glacial terminations and inceptions prior to the last termination. Stable isotope records from the same stalagmites are used to investigate changes in western Mediterranean climate and potential relationships to Mediterranean sapropel events.

  16. Extreme floods in the Mekong River Delta under climate change: combined impacts of upstream hydrological changes and sea level rise

    NASA Astrophysics Data System (ADS)

    Hoang, Long; Nguyen Viet, Dung; Kummu, Matti; Lauri, Hannu; Koponen, Jorma; van Vliet, Michelle T. H.; Supit, Iwan; Leemans, Rik; Kabat, Pavel; Ludwig, Fulco

    2016-04-01

    Extreme floods cause huge damages to human lives and infrastructure, and hamper socio-economic development in the Mekong River Delta in Vietnam. Induced by climate change, upstream hydrological changes and sea level rise are expected to further exacerbate future flood hazard and thereby posing critical challenges for securing safety and sustainability. This paper provides a probabilistic quantification of future flood hazard for the Mekong Delta, focusing on extreme events under climate change. We developed a model chain to simulate separate and combined impacts of two drivers, namely upstream hydrological changes and sea level rise on flood magnitude and frequency. Simulation results show that upstream changes and sea level rise substantially increase flood hazard throughout the whole Mekong Delta. Due to differences in their nature, two drivers show different features in their impacts on floods. Impacts of upstream changes are more dominant in floodplains in the upper delta, causing an increase of up to +0.80 m in flood depth. Sea level rise introduces flood hazard to currently safe areas in the middle and coastal delta zones. A 0.6 m rise in relative sea level causes an increase in flood depth between 0.10 and 0.70 m, depending on location by 2050s. Upstream hydrological changes and sea level rise tend to intensify each other's impacts on floods, resulting in stronger combined impacts than linearly summed impacts of each individual driver. Substantial increase of future flood hazard strongly requires better flood protection and more flood resilient development for the Mekong Delta. Findings from this study can be used as quantified physical boundary conditions to develop flood management strategies and strategic delta management plans.

  17. Contribution of climate-driven change in continental water storage to recent sea-level rise

    USGS Publications Warehouse

    Milly, P.C.D.; Cazenave, A.; Gennero, M.C.

    2003-01-01

    Using a global model of continental water balance, forced by interannual variations in precipitation and near-surface atmospheric temperature for the period 1981-1998, we estimate the sea-level changes associated with climate-driven changes in storage of water as snowpack, soil water, and ground water; storage in ice sheets and large lakes is not considered. The 1981-1998 trend is estimated to be 0.12 mm/yr, and substantial interannual fluctuations are inferred; for 1993-1998, the trend is 0.25 mm/yr. At the decadal time scale, the terrestrial contribution to eustatic (i.e., induced by mass exchange) sea-level rise is significantly smaller than the estimated steric (i.e., induced by density changes) trend for the same period, but is not negligibly small. In the model the sea-level rise is driven mainly by a downtrend in continental precipitation during the study period, which we believe was generated by natural variability in the climate system.

  18. Contribution of climate-driven change in continental water storage to recent sea-level rise.

    PubMed

    Milly, P C D; Cazenave, A; Gennero, C

    2003-11-11

    Using a global model of continental water balance, forced by interannual variations in precipitation and near-surface atmospheric temperature for the period 1981-1998, we estimate the sea-level changes associated with climate-driven changes in storage of water as snowpack, soil water, and ground water; storage in ice sheets and large lakes is not considered. The 1981-1998 trend is estimated to be 0.12 mm/yr, and substantial interannual fluctuations are inferred; for 1993-1998, the trend is 0.25 mm/yr. At the decadal time scale, the terrestrial contribution to eustatic (i.e., induced by mass exchange) sea-level rise is significantly smaller than the estimated steric (i.e., induced by density changes) trend for the same period, but is not negligibly small. In the model the sea-level rise is driven mainly by a downtrend in continental precipitation during the study period, which we believe was generated by natural variability in the climate system.

  19. Deep-sea ostracode species diversity: Response to late Quaternary climate change

    USGS Publications Warehouse

    Cronin, T. M.; DeMartino, D.M.; Dwyer, G.S.; Rodriguez-Lazaro, J.

    1999-01-01

    Late Quaternary ostracode assemblages from the North Atlantic Ocean were studied to establish the effect of climatic changes of the past 210,000 yr (marine oxygen isotope stages 7-1) on deep-sea benthic biodiversity and faunal composition. Two-hundred and twenty five samples from the Chain 82-24 Core 4PC (41??43'N, 32??51'W, 3427 m water depth) on the western Mid-Atlantic Ridge revealed high amplitude fluctuations in ostracode abundance and diversity coincident with orbital and suborbital scale climate oscillations measured by several paleoceanographic proxy records. During the past 210,000 yr, ostracode biodiversity as measured by species number (S) and the Shannon-Weaver index, H(S), oscillated from H(S) = 0.4 during glacial periods (marine isotope stages 6, 5d, 5b, 4, and 2) to H(S) = 1.1 during interglacial and interstadial periods (stages 7, 5e, 5c, 5a, 3 and 1). A total of 23 diversity peaks could be recognized. Eleven of these signify major periods of high diversity [H(S) > 0.8, S = 10-21] occurring every 15-20 ka. Twelve were minor peaks which may represent millennial-scale diversity oscillations. The composition of ostracode assemblages varies with Krithe-dominated assemblages characterizing glacial intervals, and Argilloecia-Cytheropteron characterizing deglacials, and trachyleberid genera (Poseidonamicus, Echinocythereis, Henryhowella, Oxycythereis) abundant during interglacials. Diversity and faunal composition changes can be matched to independent deep-sea paleoceanographic tracers such as benthic foraminiferal carbon isotopes, Krithe trace elements (Mg/Ca ratios), and to North Atlantic region climate records such as Greenland ice cores. When interpreted in light of ostracode species' ecology, these faunal and diversity patterns provide evidence that deep-sea benthic ecosystems experience significant reorganization in response to climate changes over orbital to millennial timescales.

  20. Assessment of Hammocks (Petenes) Resilience to Sea Level Rise Due to Climate Change in Mexico.

    PubMed

    Hernández-Montilla, Mariana C; Martínez-Morales, Miguel Angel; Posada Vanegas, Gregorio; de Jong, Bernardus H J

    2016-01-01

    There is a pressing need to assess resilience of coastal ecosystems against sea level rise. To develop appropriate response strategies against future climate disturbances, it is important to estimate the magnitude of disturbances that these ecosystems can absorb and to better understand their underlying processes. Hammocks (petenes) coastal ecosystems are highly vulnerable to sea level rise linked to climate change; their vulnerability is mainly due to its close relation with the sea through underground drainage in predominantly karstic soils. Hammocks are biologically important because of their high diversity and restricted distribution. This study proposes a strategy to assess resilience of this coastal ecosystem when high-precision data are scarce. Approaches and methods used to derive ecological resilience maps of hammocks are described and assessed. Resilience models were built by incorporating and weighting appropriate indicators of persistence to assess hammocks resilience against flooding due to climate change at "Los Petenes Biosphere Reserve", in the Yucatán Peninsula, Mexico. According to the analysis, 25% of the study area is highly resilient (hot spots), whereas 51% has low resilience (cold spots). The most significant hot spot clusters of resilience were located in areas distant to the coastal zone, with indirect tidal influence, and consisted mostly of hammocks surrounded by basin mangrove and floodplain forest. This study revealed that multi-criteria analysis and the use of GIS for qualitative, semi-quantitative and statistical spatial analyses constitute a powerful tool to develop ecological resilience maps of coastal ecosystems that are highly vulnerable to sea level rise, even when high-precision data are not available. This method can be applied in other sites to help develop resilience analyses and decision-making processes for management and conservation of coastal areas worldwide.

  1. Assessment of Hammocks (Petenes) Resilience to Sea Level Rise Due to Climate Change in Mexico.

    PubMed

    Hernández-Montilla, Mariana C; Martínez-Morales, Miguel Angel; Posada Vanegas, Gregorio; de Jong, Bernardus H J

    2016-01-01

    There is a pressing need to assess resilience of coastal ecosystems against sea level rise. To develop appropriate response strategies against future climate disturbances, it is important to estimate the magnitude of disturbances that these ecosystems can absorb and to better understand their underlying processes. Hammocks (petenes) coastal ecosystems are highly vulnerable to sea level rise linked to climate change; their vulnerability is mainly due to its close relation with the sea through underground drainage in predominantly karstic soils. Hammocks are biologically important because of their high diversity and restricted distribution. This study proposes a strategy to assess resilience of this coastal ecosystem when high-precision data are scarce. Approaches and methods used to derive ecological resilience maps of hammocks are described and assessed. Resilience models were built by incorporating and weighting appropriate indicators of persistence to assess hammocks resilience against flooding due to climate change at "Los Petenes Biosphere Reserve", in the Yucatán Peninsula, Mexico. According to the analysis, 25% of the study area is highly resilient (hot spots), whereas 51% has low resilience (cold spots). The most significant hot spot clusters of resilience were located in areas distant to the coastal zone, with indirect tidal influence, and consisted mostly of hammocks surrounded by basin mangrove and floodplain forest. This study revealed that multi-criteria analysis and the use of GIS for qualitative, semi-quantitative and statistical spatial analyses constitute a powerful tool to develop ecological resilience maps of coastal ecosystems that are highly vulnerable to sea level rise, even when high-precision data are not available. This method can be applied in other sites to help develop resilience analyses and decision-making processes for management and conservation of coastal areas worldwide. PMID:27611802

  2. Assessment of Hammocks (Petenes) Resilience to Sea Level Rise Due to Climate Change in Mexico

    PubMed Central

    Posada Vanegas, Gregorio; de Jong, Bernardus H. J.

    2016-01-01

    There is a pressing need to assess resilience of coastal ecosystems against sea level rise. To develop appropriate response strategies against future climate disturbances, it is important to estimate the magnitude of disturbances that these ecosystems can absorb and to better understand their underlying processes. Hammocks (petenes) coastal ecosystems are highly vulnerable to sea level rise linked to climate change; their vulnerability is mainly due to its close relation with the sea through underground drainage in predominantly karstic soils. Hammocks are biologically important because of their high diversity and restricted distribution. This study proposes a strategy to assess resilience of this coastal ecosystem when high-precision data are scarce. Approaches and methods used to derive ecological resilience maps of hammocks are described and assessed. Resilience models were built by incorporating and weighting appropriate indicators of persistence to assess hammocks resilience against flooding due to climate change at “Los Petenes Biosphere Reserve”, in the Yucatán Peninsula, Mexico. According to the analysis, 25% of the study area is highly resilient (hot spots), whereas 51% has low resilience (cold spots). The most significant hot spot clusters of resilience were located in areas distant to the coastal zone, with indirect tidal influence, and consisted mostly of hammocks surrounded by basin mangrove and floodplain forest. This study revealed that multi-criteria analysis and the use of GIS for qualitative, semi-quantitative and statistical spatial analyses constitute a powerful tool to develop ecological resilience maps of coastal ecosystems that are highly vulnerable to sea level rise, even when high-precision data are not available. This method can be applied in other sites to help develop resilience analyses and decision-making processes for management and conservation of coastal areas worldwide. PMID:27611802

  3. Variability in climate change simulations affects needed long-term riverine nutrient reductions for the Baltic Sea.

    PubMed

    Bring, Arvid; Rogberg, Peter; Destouni, Georgia

    2015-06-01

    Changes to runoff due to climate change may influence management of nutrient loading to the sea. Assuming unchanged river nutrient concentrations, we evaluate the effects of changing runoff on commitments to nutrient reductions under the Baltic Sea Action Plan. For several countries, climate projections point to large variability in load changes in relation to reduction targets. These changes either increase loads, making the target more difficult to reach, or decrease them, leading instead to a full achievement of the target. The impact of variability in climate projections varies with the size of the reduction target and is larger for countries with more limited commitments. In the end, a number of focused actions are needed to manage the effects of climate change on nutrient loads: reducing uncertainty in climate projections, deciding on frameworks to identify best performing models with respect to land surface hydrology, and increasing efforts at sustained monitoring of water flow changes. PMID:26022321

  4. Looking for evidence of climate change impacts in the eastern Irish Sea

    NASA Astrophysics Data System (ADS)

    Esteves, L. S.; Williams, J. J.; Brown, J. M.

    2011-06-01

    Although storminess is often cited as a driver of long-term coastal erosion, a lack of suitable datasets has only allowed objective assessment of this claim in a handful of case studies. This reduces our ability to understand and predict how the coastline may respond to an increase in "storminess" as suggested by global and regional climate models. With focus on 16 km of the Sefton coastline bordering the eastern Irish Sea (UK), this paper analyses available measured datasets of water level, surge level, wave height, wind speed and barometric pressure with the objective of finding trends in metocean climate that are consistent with predictions. The paper then examines rates of change in shoreline position over the period 1894 to 2005 with the aim of establishing relationships with climatic variability using a range of measured and modelled metocean parameters (with time spans varying from two to eight decades). With the exception of the mean monthly wind speed, available metocean data do not indicate any statistically significant changes outside seasonal and decadal cycles. No clear relationship was found between changes in metocean conditions and rates of shoreline change along the Sefton coast. High interannual variability and the lack of long-term measurements make unambiguous correlations between climate change and shoreline evolution problematic. However, comparison between the North Atlantic Oscillation winter index (NAOw) and coastline changes suggest increased erosion at times of decreasing NAOw values and reduced erosion at times of increasing NAOw values. Erosion tends to be more pronounced when decreasing NAOw values lead to a strong negative NAO phase. At present, anthropogenic changes in the local sediment budget and the short-term impact of extreme events are still the largest threat likely to affect coastal flooding and erosion risk in the short- and medium-term. Nevertheless, the potential impacts of climate change in the long-term should not be

  5. Global Climate Change.

    ERIC Educational Resources Information Center

    Hall, Dorothy K.

    1989-01-01

    Discusses recent changes in the Earth's climate. Summarizes reports on changes related to carbon dioxide, temperature, rain, sea level, and glaciers in polar areas. Describes the present effort to measure the changes. Lists 16 references. (YP)

  6. Holocene shelf sedimentation patterns off equatorial East Africa constrained by climatic and sea-level changes

    NASA Astrophysics Data System (ADS)

    Liu, Xiting; Rendle-Bühring, Rebecca; Meyer, Inka; Henrich, Rüdiger

    2016-01-01

    Equatorial East Africa experienced significant variations in paleoclimatic and paleoceanographic conditions during the Holocene. These environmental changes influenced sedimentation patterns on the continental shelf. To date, however, little is known about the sediment source, its transport to, and deposition on, the Tanzanian shelf. This paper presents a new high-resolution Holocene sedimentary record off northeast Tanzania (equatorial East Africa) and provides insights into how sedimentation patterns responded to climatic and oceanographic changes during the Holocene. Based on grain-size distribution patterns and mineral assemblages, three types of shelf sediments were identified: Type I (fine-grained terrigenous sediment) is dominated by clay minerals that originated from continental weathering; Type II (coarse-grained terrigenous sediment) is mainly composed of feldspar and quartz, derived from reworking of pre-existing deposits; and Type III (biogenic marine sediment), with low- and high-magnesium calcite, was produced by marine carbonate-secreting organisms. The high input of Type I sediment during the early Holocene (10-8 cal kyr BP) was caused by river mouth bypassing. This supply-dominated regime was controlled by intense river discharge and subsequent resuspension of mud in shelf settings, responding to the humid climate in the hinterland and sea-level rise with low rate off Tanzania. The first occurrence of Type II sediments was around 8 cal kyr BP and dominated when sedimentation rates lowered. This accommodation-dominated regime was caused by shoreface bypassing due to an arid climate and sea-level highstand. Type III sediments increased significantly from the early to late Holocene, resulting from the weakening dilution effect of the terrigenous component. The sedimentation pattern on the Tanzanian shelf shifted from allochthonous to autochthonous sedimentation constrained by climatic changes and relative sea-level fluctuations at the end of the early

  7. Adapting to climate change despite scientific uncertainty: A case study of coastal protection from sea-level rise in Kiribati

    NASA Astrophysics Data System (ADS)

    Donner, S. D.

    2013-12-01

    Climate change adaptation is an increasing focus of international aid. At recent meetings of the parties to the United Nations Framework Convention on Climate Change (UNFCCC), the developed world agreed to rapidly increase international assistance to help developing countries, like the low-lying island nation of Kiribati, respond to the impacts of climate change. These emerging adaptation efforts must proceed despite the large and partially irreducible scientific uncertainty about the magnitude of those future climate impacts. In this study, we use the example of efforts to adapt to sea-level rise in Kiribati to document the challenges facing such internationally-funded climate change adaptation projects given the scientific uncertainty about climate impacts. Drawing on field and document research, we describe the scientific uncertainty about projected sea-level rise in Tarawa, the capital of Kiribati, how that uncertainty can create trade-offs between adaptation measures, and the social, political and economic context in which adaptation decisions must be made. The analysis shows there is no 'silver bullet' adaptation strategy in countries like Kiribati, given the long-term scientific uncertainty about sea-level rise and the environment of climate change aid. The existence of irreducible scientific uncertainty does not preclude effective climate change adaptation, but instead requires adaptation programs that embrace multiple strategies and planning horizons, and continually build on and re-adjust previous investments. This work highlights the importance of sustained international climate change financing, as proposed in UNFCCC negotiations.

  8. Numerical modelling of climate change impacts on freshwater lenses on the North Sea Island of Borkum

    NASA Astrophysics Data System (ADS)

    Sulzbacher, H.; Wiederhold, H.; Siemon, B.; Grinat, M.; Igel, J.; Burschil, T.; Günther, T.; Hinsby, K.

    2012-03-01

    A numerical variable-density groundwater model is set up for the North Sea Island of Borkum to estimate climate change impacts on coastal aquifers and especially the situation of barrier islands in the Wadden Sea. The database includes information from boreholes, a seismic survey, a helicopter-borne electromagnetic survey (HEM), monitoring of the freshwater-saltwater boundary by vertical electrode chains in two boreholes, measurements of groundwater table, pumping and slug tests, as well as water samples. Based on a statistical analysis of borehole columns, seismic sections and HEM, a hydrogeological model is set up. The groundwater model is developed using the finite-element programme FEFLOW. The variable-density groundwater model is calibrated on the basis of hydraulic, hydrological and geophysical data, in particular spatial HEM and local monitoring data. Verification runs with the calibrated model show good agreement between measured and computed hydraulic heads. A good agreement is also obtained between measured and computed density or total dissolved solids data for both the entire freshwater lens on a large scale and in the area of the well fields on a small scale. For simulating future changes in this coastal groundwater system until the end of the current century we use the climate scenario A2, specified by the Intergovernmental Panel on Climate Change and in particular the data for the German North Sea coast. Simulation runs show proceeding salinization with time beneath the well fields of the two waterworks Waterdelle and Ostland. The modelling study shows that spreading of well fields is an appropriate protection measure against excessive salinization of the water supply until the end of the current century.

  9. How climate change threats water resource: the case of the Thau coastal lagoon (Mediterranean Sea, France)

    NASA Astrophysics Data System (ADS)

    La Jeunesse, Isabelle; Sellami, Haykel; Cirelli, Claudia

    2014-05-01

    The latest reports of the intergovernmental panel on climate change explained that the Mediterranean regions are especially vulnerable to the impacts of climate change. These latest are expected to have strong impacts on the management of water resources and on regional economies. The aim of this paper is to discuss impacts of climate changes on the Thau case study in relation to the evolution of water balance, water uses and adaptation to climate change. The Thau coastal lagoon is located in the Mediterranean coast in south of France in the Languedoc-Roussillon Region. Economic activities are diverse from shellfish farming, fertilizers industries to agriculture and tourism. However, tourism and shellfish farming are of major importance for local economy. If tourism is mainly turned to the Sea coast, shellfishes grow within the lagoon and rely on water quality. Previous studies have demonstrated the link between the coastal lagoon water quality and inputs of freshwater from the catchment. Thus, changes in rainfalls, runoff and water balance would not only affect water uses but also water quality. Climate changes projections are presented following the implementation of 4 downscaled climatic models. Impacts on water balance are modelled with SWAT (Soil Water Assessment Tool) for 2041-2070 compared to the 1971-2000 reference period. The decrease of precipitations and water balance will impact discharges and thus decrease the freshwater inputs to the coastal lagoon. A study of water uses conducted in interactions with stakeholders within the Thau area has permitted to assess both current and evolution of water uses. It has revealed local water resources are depleting while water demand is increasing and is planned to continue to increase in the really near future. To prevent water scarcity events, mainly due to the climate change context, the Regional authorities have connected the catchment to the Rhône river to import water. The conclusion of this study is while

  10. Iceberg severity off eastern North America: Its relationship to sea ice variability and climate change

    SciTech Connect

    Marko, J.R.; Fissel, D.B. ); Wadhams, P. ); Kelly, P.M. ); Brown, R.D. )

    1994-09-01

    Iceberg trajectory, deterioration (mass loss), and sea ice data are reviewed to identify the sources of observed interannual and seasonal variations in the numbers of icebergs passing south of 48[degrees]N off eastern North America. The results show the dominant role of sea ice in the observed variations. Important mechanisms involved include both seasonal modulation of the southerly iceberg flow by ice cover control of probabilities for entrapment and decay in shallow water, and the suppression of iceberg melt/deterioration rates by high concentrations of sea ice. The Labrador spring ice extent, shown to be the critical parameter in interannual iceberg number variability, was found to be either determined by or closely correlated with midwinter Davis Strait ice extents. Agreement obtained between observed year-to-year and seasonal number variations with computations based upon a simple iceberg dissipation model suggests that downstream iceberg numbers are relatively insensitive to iceberg production rates and to fluctuations in southerly iceberg fluxes in areas north of Baffin Island. Past variations in the Davis Strait ice index and annual ice extents are studied to identify trends and relationships between regional and larger-scale global climate parameters. It was found that, on decadal timescales in the post-1960 period of reasonable data quality, regional climate parameters have varied, roughly, out of phase with corresponding global and hemispheric changes. These observations are compared with expectations in terms of model results to evaluate current GCM-based capabilities for simulating recent regional behavior. 64 refs., 11 figs., 3 tabs.

  11. Climate Change and the Potential Spreading of Marine Mucilage and Microbial Pathogens in the Mediterranean Sea

    PubMed Central

    Danovaro, Roberto; Fonda Umani, Serena; Pusceddu, Antonio

    2009-01-01

    Background Marine snow (small amorphous aggregates with colloidal properties) is present in all oceans of the world. Surface water warming and the consequent increase of water column stability can favour the coalescence of marine snow into marine mucilage, large marine aggregates representing an ephemeral and extreme habitat. Marine mucilage characterize aquatic systems with altered environmental conditions. Methodology/Principal Findings We investigated, by means of molecular techniques, viruses and prokaryotes within the mucilage and in surrounding seawater to examine the potential of mucilage to host new microbial diversity and/or spread marine diseases. We found that marine mucilage contained a large and unexpectedly exclusive microbial biodiversity and hosted pathogenic species that were absent in surrounding seawater. We also investigated the relationship between climate change and the frequency of mucilage in the Mediterranean Sea over the last 200 years and found that the number of mucilage outbreaks increased almost exponentially in the last 20 years. The increasing frequency of mucilage outbreaks is closely associated with the temperature anomalies. Conclusions/Significance We conclude that the spreading of mucilage in the Mediterranean Sea is linked to climate-driven sea surface warming. The mucilage can act as a controlling factor of microbial diversity across wide oceanic regions and could have the potential to act as a carrier of specific microorganisms, thereby increasing the spread of pathogenic bacteria. PMID:19759910

  12. Climate change and fishing: a century of shifting distribution in North Sea cod.

    PubMed

    Engelhard, Georg H; Righton, David A; Pinnegar, John K

    2014-08-01

    Globally, spatial distributions of fish stocks are shifting but although the role of climate change in range shifts is increasingly appreciated, little remains known of the likely additional impact that high levels of fishing pressure might have on distribution. For North Sea cod, we show for the first time and in great spatial detail how the stock has shifted its distribution over the past 100 years. We digitized extensive historical fisheries data from paper charts in UK government archives and combined these with contemporary data to a time-series spanning 1913-2012 (excluding both World Wars). New analysis of old data revealed that the current distribution pattern of cod - mostly in the deeper, northern- and north-easternmost parts of the North Sea - is almost opposite to that during most of the Twentieth Century - mainly concentrated in the west, off England and Scotland. Statistical analysis revealed that the deepening, northward shift is likely attributable to warming; however, the eastward shift is best explained by fishing pressure, suggestive of significant depletion of the stock from its previous stronghold, off the coasts of England and Scotland. These spatial patterns were confirmed for the most recent 3 1/2 decades by data from fisheries-independent surveys, which go back to the 1970s. Our results demonstrate the fundamental importance of both climate change and fishing pressure for our understanding of changing distributions of commercially exploited fish.

  13. The rise of global mean sea level as an indication of climate change.

    PubMed

    Etkins, R; Epstein, E S

    1982-01-15

    Rising mean sea level, it is proposed, is a significant indicator of global climate change. The principal factors that can have contributed to the observed increases of global mean sea level in recent decades are thermal expansion of the oceans and the discharge of polar ice sheets. Calculations indicate that thermal expansion cannot be the sole factor responsible for the observed rise in sea level over the last 40 years; significant discharges of polar ice must also be occurring. Global warming, due in some degree presumably to increasing atmospheric carbon dioxide, has been opposed by the extraction of heat necessary to melt the discharged ice. During the past 40 years more than 50,000 cubic kilometers of ice has been discharged and has melted, reducing the surface warming that might otherwise have occurred by as much as a factor of 2. The transfer of mass from the polar regions to a thin spherical shell covering all the oceans should have increased the earth's moment of inertia and correspondingly reduced the speed of rotation by about 1.5 parts in 10(8). This accounts for about three quarters of the observed fractional reduction in the earth's angular velocity since 1940. Monitoring of global mean sea level, ocean surface temperatures, and the earth's speed of rotation should be complemented by monitoring of the polar ice sheets, as is now possible by satellite altimetry. All parts of the puzzle need to be examined in order that a consistent picture emerge.

  14. Reducing uncertainties of local sea level projections for developing climate-change mitigation strategies

    NASA Astrophysics Data System (ADS)

    Plag, H. P.; Miller, N. L.

    2008-05-01

    Changes in Local Sea Level (LSL) may be one of the major climate change impacts requiring expensive coastal protection measures or severe adaptation strategies. In many countries, decision makers are increasingly facing decisions of whether to burden national economies with costs for coastal protection, or to risk major disasters. The decision to rebuild (e.g. New Orleans) or abandon cities or island nations (e.g. Maldives) under incrreasing risk of being devastated by a combination of storm surge and rising LSL requires an understanding of the uncertainties. Today's planning decisions will have long term implications for mitigating the potential of a slowly developing LSL rise disaster. Informed decisions will only be possible if predictions of the range of future LSL rise are made available with reliable uncertainties. State-of-the-science Earth system models cannot reliably predict climate-induced changes in LSL, hence policy- makers lack needed tools for determining best mitigation strategies. Local secular changes in LSL are the result of a location-dependent mix of various factors, including steric changes, ocean and atmospheric circulation changes, mass exchange of the ocean with terrestrial water storage and the cryosphere, and the vertical motion of the land. A major uncertainty is contributed by the uncertain response of large ice sheets on Greenland and Antarctica to climate change. Therefore, Probability Density Functions (PDF) attached to the IPCC predictions for global temperature changes over the next 100 years cannot be translated easily into PDFs for global sea level changes, and even less so for any LSL changes. We will present an observation-based approach for the prediction and probabilities of LSL changes for a wide range of scenarios needed to assess plausible future LSL trajectories at any given location. Identifying the major contributions to the uncertainties and determining their weight with respect to the overall PDF for LSL changes will

  15. Effects of tectonism, eustatic sea level fluctuations, and climatic changes on Paleogene sedimentation in California

    SciTech Connect

    Nilsen, T.H.

    1988-03-01

    Paleogene sedimentation in California was strongly influenced by syndepositional tectonism, eustatic sea level changes, and variations in climate. Tectonic activity was most important in controlling sedimentation in basins that developed in mobile areas such as the Salinian block, Coast Ranges, Transverse Ranges, southern California borderland, and along the continental slope adjacent to the trench that formed the California plate margin. Although plutonism had largely terminated in California by Paleogene time, continued uplift of the Mesozoic batholithic complexes of the Klamath Mountains, Sierra Nevada, Mojave Desert, and Salinian block yielded abundant plutoniclastic detritus to paleogene basins. Accretion of exotic terranes during the Paleocene and early eocene, major uplift of the Franciscan assemblage in various parts of California during the Eocene, syndepositional faulting in numerous areas, angular unconformities, and coarse clastic sequences that include alluvial-fan and fault-scarp breccias are features that indicate major tectonic control of sedimentation in Paleogene basins. Renewed volcanism, starting during the late Eocene in northern California in the ancestral Cascade volcanic arc, and in the late Oligocene in many other parts of California, began to supply abundant volcaniclastic sediments locally. In some relatively stable areas, such as the flanks of the Peninsular Ranges and parts of the San Joaquin and Sacramento basins, the effects of global sea level changes on the sedimentary record are easily discerned. Climatic cycles had significant control over Paleogene sedimentation in some of these stable areas.

  16. Coastal response to simultaneous mid-Holocene climate and sea-level changes: Lessons from ancient Egypt

    NASA Astrophysics Data System (ADS)

    Hein, C. J.; FitzGerald, D. M.; Milne, G. A.; Bard, K. A.; Fattovich, R.

    2011-12-01

    Coastal evolution during the Holocene has been driven by complex interactions between changes in sea level, climate, and sedimentation processes. Along the Egyptian Red Sea coast, a post-glacial marine transgression drowned a series of wadi channels, flooding their lower reaches to create shallow lagoons. Archeological investigations at one such site, Mersa / Wadi Gawasis, have uncovered the existence of an ancient Egyptian harbor along a carbonate / conglomerate terrace located 600 m landward of the modern shoreline; this discovery documented the world's earliest (3.5 - 4.0 ka) archaeological evidence of long-distance seafaring. This site is interpreted to have been a harbor servicing trade routes along the African Red Sea coast. Sedimentological, malacological, chorological, and foraminiferal analyses indicate that this harbor was located within a low energy, 6 - 8 m deep, tidal embayment that once extended ~1 km inland of the modern shore. A buried coral-beach rock platform and tidal flat sediments are found ubiquitously along the periphery of the paleo-bay and at elevations of up to 1 m above modern mean sea level. Wave-cut notches and erosional terraces observed at 1.1 - 1.8 m above modern sea level along the modern shoreline provide additional evidence of a higher-than-present stand of sea-level during the mid-Holocene. Sea-level predictions generated using a site-specific isostatic model for the northern the Red Sea confirm the presence of 0.5 - 2 m highstand at 5 ka. Reconstructions indicate that the bay at Mersa / Wadi Gawasis reached its maximum surface area prior to the highstand. Preliminary closure was driven by sediment inputs from the adjacent wadi, enhanced by the wetter climate of the African Humid Period, combined with a slowing rate of sea-level rise, thus demonstrating the dominance of sedimentary processes during this period. Following the highstand, slowly falling sea level coincidental with climatic aridization allowed for the establishment

  17. Analysis of the risk of tropical cyclones over the Mediterranean Sea with ENSEMBLES climate change scenarios

    NASA Astrophysics Data System (ADS)

    Gaertner, M. A.; Sánchez, E.; Domínguez, M.; Gil, V.; Romera, R.; Gallardo, C.

    2012-04-01

    A study by Gaertner et al. (2007) raised the possibility of tropical cyclones developing over the Mediterranean Sea under future climate change conditions. The analysis of scenario data from PRUDENCE European project for the last decades of 21st century showed a certain risk of tropical cyclone development, but with large differences among the RCMs of the ensemble. A new analysis of this risk is performed with the more recent simulations of the European project ENSEMBLES. The multi-model ensemble of ENSEMBLES project is larger and allows to explore cyclone changes for the first decades of the present century. The effect of higher horizontal resolution and the use of several different GCMs for the boundary conditions is also analysed. The new results show again a cyclone intensity increase in future decades, associated to tropical characteristics in the most intense cyclones simulated by some models, but the differences among simulations remain large.

  18. Climate change and the control of energy flow in the southeastern Bering Sea

    NASA Astrophysics Data System (ADS)

    Hunt, George L.; Stabeno, Phyllis J.

    2002-10-01

    We examine how coupling between physical and biological processes influences the production and transfer of energy to upper trophic-level species in the southeastern Bering Sea. We review time series that illustrate changes in the marine climate of the southeastern Bering Sea since the mid-1970s, particularly variability in the persistence of sea ice and the timing of its retreat. Time series (1995 - 2001) from a biophysical mooring in the middle domain of the southeastern shelf support the hypothesis that retreat of the winter sea ice before mid-March (or the failure of ice to be advected into a region) results in an open water bloom in May or June in relatively warm water (≥3°C). Conversely, when ice retreat is delayed until mid-March or later, an ice-associated bloom occurs in cold (≤0°C) water in early spring. These variations are important because the growth and production of zooplankton and the growth and survival of larval and juvenile fish are sensitive to water temperature. The Oscillating Control Hypothesis (OCH) recently proposed by Hunt et al. (2002), predicts that control of the abundance of forage fish, and in the case of walleye pollock ( Theragra chalcogramma), recruitment of large piscivorous fish, will switch from bottom-up limitation in extended periods with late ice retreat to top-down in warmer periods when ice retreat occurs before mid-March. In support of this hypothesis, we review recent data from the southeastern Bering Sea that show 2- to 13-fold changes in copepod abundance with changes in spring water temperatures of 3 to 5°C. We also provide indirect evidence that the abundance of adult pollock on the eastern Bering Sea shelf negatively affects the abundance forage fishes (including juvenile pollock) available to top predators. Although there is evidence that pollock year-class strength is positively related to temperature, we lack the time series of pollock populations in extended periods (8 - 10 years) of cold-water blooms

  19. Climatic warming and accompanying changes in the ecological regime of the Black Sea during 1990s

    NASA Astrophysics Data System (ADS)

    Oguz, Temel; Cokacar, Tulay; Malanotte-Rizzoli, Paola; Ducklow, Hugh W.

    2003-09-01

    The Black Sea ecosystem is shown to experience abrupt shifts in its all trophic levels from primary producers to apex predators in 1995-1996. It arises as a manifestation of concurrent changes in its physical climate introduced by intensive warming of its surface waters as well as abrupt increases in the mean sea level and the net annual mean fresh water flux. The warming is evident in the annual-mean sea surface temperature (SST) data by a continuous rise at a rate of ˜0.25°C per year, following a strong cooling phase in 1991-1993. The most intense warming event with ˜2°C increase in the SST took place during winters of the 1994-1996 period. It also coincides with 4 cm yr-1 net sea level rise in the basin, and substantial change in the annual mean net fresh water flux from 150 km3 yr-1 in 1993 to 420 km3 yr-1 in 1997. The subsurface signature of warming is marked by a gradual depletion of the Cold Intermediate Layer (characterized by T < 8°C) throughout the basin during the same period. Winters of the warming phase are characterized by weaker vertical turbulent mixing and upwelling velocity, stronger stratification and, subsequently, reduced upward nutrient supply from the nutricline. From 1996 onward, the major late winter-early spring peak of the classical annual phytoplankton biomass structure observed prior to mid-90s was, therefore, either weakened or disappeared altogether depending on local meteorological and oceanographic conditions during each of these years. The effect of bottom-up limited unfavorable phytoplankton growth is reflected at higher trophic levels (e.g., mesozooplankton, gelatinous macrozooplankton, and pelagic fishes) in the form of their reduced stocks after 1995.

  20. The Guayas Estuary and sea level corrections to calculate flooding areas for climate change scenarios

    NASA Astrophysics Data System (ADS)

    Moreano, H. R.; Paredes, N.

    2011-12-01

    The Guayas estuary is the inner area of the Gulf of Guayaquil, it holds a water body of around 5000 km2 and the Puna island divides the water flow in two main streams : El Morro and Estero Salado Channel (length: 90 Km.) and Jambeli and Rio Guayas Channel (length: 125km.). The geometry of the estuarine system with the behavior of the tidal wave (semidiurnal) makes tidal amplitude higher at the head than at the mouth, whereas the wave crest at the head is delayed from one and a half to two hours from that at the mouth and sea level recorded by gages along the estuary are all different because of the wave propagation and mean sea level (msl) calculated for each gage show differences with that of La Libertad which is the base line for all altitudes on land (zero level). A leveling and calculations were made to correct such differences in a way that all gages (msl) records were linked to La Libertad and this in turn allowed a better estimates of flooding areas and draw them on topographic maps where zero level corresponds to the mean sea level at La Libertad. The procedure and mathematical formulation could be applied to any estuary or coastal area and it is a useful tool to calculate such areas especially when impacts are on people or capital goods and related to climate change scenarios.

  1. Ecosystem responses in the southern Caribbean Sea to global climate change

    PubMed Central

    Taylor, Gordon T.; Muller-Karger, Frank E.; Thunell, Robert C.; Scranton, Mary I.; Astor, Yrene; Varela, Ramon; Ghinaglia, Luis Troccoli; Lorenzoni, Laura; Fanning, Kent A.; Hameed, Sultan; Doherty, Owen

    2012-01-01

    Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indices. Monthly observations from the CARIACO Ocean Time-Series between 1996 and 2010 document significant decadal scale trends, including a net sea surface temperature (SST) rise of ∼1.0 ± 0.14 °C (±SE), intensified stratification, reduced delivery of upwelled nutrients to surface waters, and diminished phytoplankton bloom intensities evident as overall declines in chlorophyll a concentrations (ΔChla = −2.8 ± 0.5%⋅y−1) and net primary production (ΔNPP = −1.5 ± 0.3%⋅y−1). Additionally, phytoplankton taxon dominance shifted from diatoms, dinoflagellates, and coccolithophorids to smaller taxa after 2004, whereas mesozooplankton biomass increased and commercial landings of planktivorous sardines collapsed. Collectively, our results reveal an ecological state change in this planktonic system. The weakening trend in Trade Winds (−1.9 ± 0.3%⋅y−1) and dependent local variables are largely explained by trends in two climatic indices, namely the northward migration of the Azores High pressure center (descending branch of Hadley cell) by 1.12 ± 0.42°N latitude and the northeasterly progression of the ITCZ Atlantic centroid (ascending branch of Hadley cell), the March position of which shifted by about 800 km between 1996 and 2009. PMID:23071299

  2. Ecosystem responses in the southern Caribbean Sea to global climate change.

    PubMed

    Taylor, Gordon T; Muller-Karger, Frank E; Thunell, Robert C; Scranton, Mary I; Astor, Yrene; Varela, Ramon; Ghinaglia, Luis Troccoli; Lorenzoni, Laura; Fanning, Kent A; Hameed, Sultan; Doherty, Owen

    2012-11-20

    Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indices. Monthly observations from the CARIACO Ocean Time-Series between 1996 and 2010 document significant decadal scale trends, including a net sea surface temperature (SST) rise of ∼1.0 ± 0.14 °C (±SE), intensified stratification, reduced delivery of upwelled nutrients to surface waters, and diminished phytoplankton bloom intensities evident as overall declines in chlorophyll a concentrations (ΔChla = -2.8 ± 0.5%⋅y(-1)) and net primary production (ΔNPP = -1.5 ± 0.3%⋅y(-1)). Additionally, phytoplankton taxon dominance shifted from diatoms, dinoflagellates, and coccolithophorids to smaller taxa after 2004, whereas mesozooplankton biomass increased and commercial landings of planktivorous sardines collapsed. Collectively, our results reveal an ecological state change in this planktonic system. The weakening trend in Trade Winds (-1.9 ± 0.3%⋅y(-1)) and dependent local variables are largely explained by trends in two climatic indices, namely the northward migration of the Azores High pressure center (descending branch of Hadley cell) by 1.12 ± 0.42°N latitude and the northeasterly progression of the ITCZ Atlantic centroid (ascending branch of Hadley cell), the March position of which shifted by about 800 km between 1996 and 2009.

  3. Ecosystem responses in the southern Caribbean Sea to global climate change.

    PubMed

    Taylor, Gordon T; Muller-Karger, Frank E; Thunell, Robert C; Scranton, Mary I; Astor, Yrene; Varela, Ramon; Ghinaglia, Luis Troccoli; Lorenzoni, Laura; Fanning, Kent A; Hameed, Sultan; Doherty, Owen

    2012-11-20

    Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indices. Monthly observations from the CARIACO Ocean Time-Series between 1996 and 2010 document significant decadal scale trends, including a net sea surface temperature (SST) rise of ∼1.0 ± 0.14 °C (±SE), intensified stratification, reduced delivery of upwelled nutrients to surface waters, and diminished phytoplankton bloom intensities evident as overall declines in chlorophyll a concentrations (ΔChla = -2.8 ± 0.5%⋅y(-1)) and net primary production (ΔNPP = -1.5 ± 0.3%⋅y(-1)). Additionally, phytoplankton taxon dominance shifted from diatoms, dinoflagellates, and coccolithophorids to smaller taxa after 2004, whereas mesozooplankton biomass increased and commercial landings of planktivorous sardines collapsed. Collectively, our results reveal an ecological state change in this planktonic system. The weakening trend in Trade Winds (-1.9 ± 0.3%⋅y(-1)) and dependent local variables are largely explained by trends in two climatic indices, namely the northward migration of the Azores High pressure center (descending branch of Hadley cell) by 1.12 ± 0.42°N latitude and the northeasterly progression of the ITCZ Atlantic centroid (ascending branch of Hadley cell), the March position of which shifted by about 800 km between 1996 and 2009. PMID:23071299

  4. Rapid Climatic and Oceanographic Changes in the Okhotsk Sea during the Holocene

    NASA Astrophysics Data System (ADS)

    Lembke-Jene, L.; Tiedemann, R.; Nuernberg, D.

    2007-12-01

    We report on records of centennial- to millennial-scale climatic changes in the Okhotsk Sea and the adjacent continental Amur river watershed, thereby confirming the significant potential of this realm for paleoclimatic reconstructions. High biogenic productivity, delivery of Ice-Rafted Debris (IRD), highly variable hydrographic conditions, and terrigenous sediment supply by the Amur's drainage system closely interact in this region and form the depositional environment. According to our stratigraphic framework, average sedimentation rates in the hemipelagic sediment cores vary between 30 and 160 cm/kyr. Thus, our study provides insight into rapid climatic changes on millenial and shorter timescales for the last deglaciation and the Holocene. Biogenic opal and chlorines serve as biogenic productivity proxies, elemental compositions derived from XRF-scanning as indicators for riverine sediment supply and sea- ice action. Whereas these datasets provide high-resolution records, stable isotope data of benthic and planktic foraminifera as well as countings of terrestrial pollen and IRD data supplement our results on lower temporal scales. The last deglaciation is characterized by repeated pronounced maxima in IRD and according elemental concentrations, pointing to a high supply of terrigenous siliciclastics. During the Holocene, high-frequency oscillations in Amur river discharge can be correlated to the oxygen isotope record of the Greenland NGRIP ice core. We observe significant cyclicities within the millennial and centennial range with a mid-Holocene shift in the significant frequencies. As these periodicities are partly known from other low-latitudinal, monsoonal reference records, these findings may support the notion of a transmission of low latitude climate forcing to the higher latitudes, possibly via freshwater discharge and latent heat transport by the Amur. From ca. 6.5 kyr BP onwards, we recognize a Holocene climatic optimum in various proxy records

  5. Impact of climate change and sea level rise on a coastal aquifer, Central Vietnam

    NASA Astrophysics Data System (ADS)

    Beyen, Ine; Batelaan, Okke; Thanh Tam, Vu

    2014-05-01

    The Gio Linh district in the Quang Tri province, Central Vietnam has, like many other coastal areas in the world, to deal with negative impacts of Global Climate Change (GCC) and sea level rise (SLR). This research aims at investigating the impact of GCC/SLR and designing an adaptive water use plan till the year 2030 for the 150,000 local residents of the Gio Linh district and the city of Dong Ha. The coastal plain covers an area of about 450 km2 between the rivers Ben Hai in the North and Thach Han in the South. The area has a tropical monsoon climate which is characterized by an average precipitation of 1500 to 2700 mm in nearly 180 days from August to April. GCC/SLR scenarios are built and assessed for estimating the changes in hydrometeorological conditions of the study area. Depending on the level of gas emission the sea level is expected to rise 7-9 cm by 2020 and around 11-14 cm by 2030 for low to high gas emission respectively. The salt-freshwater interface is expected to experience an inland shift due to SLR, affecting the amount of exploitable groundwater for drinking and irrigation water production. Water production mainly comes from shallow aquifers in unconsolidated Quarternary coastal formations. These geological formations have a highly heterogeneous lithology. A 3D groundwater model is built to study possible seawater intrusion under the changing conditions. Data from meteorological stations over a period of about 30 years and some data from 63 boreholes in and around the Gio Linh district are available. Geophysical measurements have been carried out recently and in the past and are used to support the model.

  6. Sensitivity of sediment magnetic records to climate change during Holocene for the northern South China Sea

    NASA Astrophysics Data System (ADS)

    Ouyang, Tingping; Li, Mingkun; Zhao, Xiang; Zhu, Zhaoyu; Tian, Chengjing; Qiu, Yan; Peng, Xuechao; Hu, Qiao

    2016-05-01

    Magnetic property has been proved to be a sensitive proxy to climate change for both terrestrial and marine sediments. Based on the schedule frame established by AMS 14C dating of foraminifera, detail magnetic analyses were performed for core PC24 sediments at sampling intervals of 2 cm to discuss magnetic sensitivity of marine sediment to climate during Holocene for the northern South China Sea. The results indicated that: 1) Concentration dependent magnetic parameters are positive corresponding to variation of temperature. The frequency dependent susceptibility coefficient basically reflected the variation in humidity; 2) XARM/SIRM was more sensitive to detrital magnetite particles and SIRM/X was more effective to biogenic magnetite particles. Variations of XARM/SIRM and SIRM/X are corresponding to precipitation and temperature, respectively; 3) the Holocene Megathermal in the study area was identified as 7.5-3.4 cal. ka BP. The warmest stage of Holocene for the study area should be during 6.1 to 3.9 cal. ka BP; 4) The 8 ka cold event was characterized as cold and dry during 8.55 to 8.25 cal. ka BP; 5) During early and middle Holocene, the climate combinations were warm dry and cold wet. It turned to warm and wet after 2.7 cal. ka BP.

  7. Toward a dynamic biogeochemical division of the Mediterranean Sea in a context of global climate change

    NASA Astrophysics Data System (ADS)

    Reygondeau, Gabriel; Olivier Irisson, Jean; Guieu, Cecile; Gasparini, Stephane; Ayata, Sakina; Koubbi, Philippe

    2013-04-01

    In recent decades, it has been found useful to ecoregionalise the pelagic environment assuming that within each partition environmental conditions are distinguishable and unique. Indeed, each partition of the ocean that is proposed aimed to delineate the main oceanographical and ecological patterns to provide a geographical framework of marine ecosystems for ecological studies and management purposes. The aim of the present work is to integrate and process existing data on the pelagic environment of the Mediterranean Sea in order to define biogeochemical regions. Open access databases including remote sensing observations, oceanographic campaign data and physical modeling simulations are used. These various dataset allow the multidisciplinary view required to understand the interactions between climate and Mediterranean marine ecosystems. The first step of our study has consisted in a statistical selection of a set of crucial environmental factors to propose the most parsimonious biogeographical approach that allows detecting the main oceanographic structure of the Mediterranean Sea. Second, based on the identified set of environmental parameters, both non-hierarchical and hierarchical clustering algorithms have been tested. Outputs from each methodology are then inter-compared to propose a robust map of the biotopes (unique range of environmental parameters) of the area. Each biotope was then modeled using a non parametric environmental niche method to infer a dynamic biogeochemical partition. Last, the seasonal, inter annual and long term spatial changes of each biogeochemical regions were investigated. The future of this work will be to perform a second partition to subdivide the biogeochemical regions according to biotic features of the Mediterranean Sea (ecoregions). This second level of division will thus be used as a geographical framework to identify ecosystems that have been altered by human activities (i.e. pollution, fishery, invasive species) for the

  8. Global Sea Surface Temperature and Ecosystem Change Across the Mid-Miocene Climatic Optimum

    NASA Astrophysics Data System (ADS)

    Veenstra, T. J. T.; Bakker, V. B.; Sangiorgi, F.; Peterse, F.; Schouten, S.; Sluijs, A.

    2015-12-01

    The Mid-Miocene Climatic Optimum (MMCO) (ca. 17 to 14 Ma) is generally considered as the warmest episode of the Neogene based on deep marine oxygen isotope records and terrestrial plant fossils. To date, however, reasonable resolution high-quality sea surface temperature (SST) proxy records spanning its onset are scarce at best. For the remainder of the MMCO, reliable SST records are absent from the tropics and very scarce in temperate and polar regions. This leaves the question if the MMCO was truly associated with global warming and if this warming was associated with biotic change. We use organic biomarker paleothermometry (Uk'37 and TEX86) to reconstruct SST across the MMCO at four locations along a pole-to-pole transect in the Atlantic and Pacific Ocean. Additionally, we use marine palynology (mostly dinoflagellate cysts) to assess ecosystem change at these locations. This study includes the first tropical biomarker-based SST records of the MMCO. Together with new and existing SST records from higher latitudes and the corresponding palynological records, they provide new insights in the temporal and spatial development of the MMCO. Our results indicate that Mid-Miocene warming was most prominent in the Norwegian Sea, showed a more complex, perhaps upwelling-related pattern in a tropical location, and was small in the Southern Hemisphere.

  9. Baltic Sea ecosystem-based management under climate change: Synthesis and future challenges.

    PubMed

    Blenckner, Thorsten; Österblom, Henrik; Larsson, Per; Andersson, Agneta; Elmgren, Ragnar

    2015-06-01

    Ecosystem-based management (EBM) has emerged as the generally agreed strategy for managing ecosystems, with humans as integral parts of the managed system. Human activities have substantial effects on marine ecosystems, through overfishing, eutrophication, toxic pollution, habitat destruction, and climate change. It is important to advance the scientific knowledge of the cumulative, integrative, and interacting effects of these diverse activities, to support effective implementation of EBM. Based on contributions to this special issue of AMBIO, we synthesize the scientific findings into four components: pollution and legal frameworks, ecosystem processes, scale-dependent effects, and innovative tools and methods. We conclude with challenges for the future, and identify the next steps needed for successful implementation of EBM in general and specifically for the Baltic Sea. PMID:26022332

  10. Baltic Sea ecosystem-based management under climate change: Synthesis and future challenges.

    PubMed

    Blenckner, Thorsten; Österblom, Henrik; Larsson, Per; Andersson, Agneta; Elmgren, Ragnar

    2015-06-01

    Ecosystem-based management (EBM) has emerged as the generally agreed strategy for managing ecosystems, with humans as integral parts of the managed system. Human activities have substantial effects on marine ecosystems, through overfishing, eutrophication, toxic pollution, habitat destruction, and climate change. It is important to advance the scientific knowledge of the cumulative, integrative, and interacting effects of these diverse activities, to support effective implementation of EBM. Based on contributions to this special issue of AMBIO, we synthesize the scientific findings into four components: pollution and legal frameworks, ecosystem processes, scale-dependent effects, and innovative tools and methods. We conclude with challenges for the future, and identify the next steps needed for successful implementation of EBM in general and specifically for the Baltic Sea.

  11. Global Climate Change Consequences Changing the Middle Sea Level in the Brazilian Coast: Impacts on Ceará State

    NASA Astrophysics Data System (ADS)

    Lacerda, E. G.; Pires, L. B. M.; Pinto, V. K. E.

    2015-12-01

    Since the Industrial Revolution, man started to generate increasing amounts of waste and pollutants, which on a large scale in the long term is causing a series of climate change consequences, both globally as well as locally. One of the many effects of these changes has been reflected in the ocean levels, depending on various factors. Thus, the population living in coastal areas suffers from the negative effects of the advancement of ocean waters. The coast of northeastern Brazil is an example of this, especially the state of Ceará coast. The state of Ceará has 573 km of coastline, a region that has suffered extensive erosion, in which the Middle Sea Level (MSL) changes exert a significant influence. The coastal plain is a strip of land of small extent, with an average width of 2.5 km, formed depending on the availability of high sediment stocks provided through the action of wind, marine, or river processes, individually in combination with each other. In many beaches it is observed that the strip of beach is narrow due to the presence of topographic elevations carved into sharp cliffs. Between periods of high tide and low tide, often rocky beach features are observed that have recently formed. The waves control the stretches of beach which are mostly sandy. This paper presents a survey about the evidence already apparent on the rise in the MSL and correlates it with the advance of the sea on the coast of Ceará, as well as assesses the possible consequences of this process. Therefore, a literature search was conducted in relevant scientific publications. The data used are from the station "Global Sea Level Observing System - GLOSS" which maintains a tide gauge installed in Ceará in Fortaleza. The analyses show that the phenomenon has caused a lot of inconvenience to the people, streets have disappeared, as well as several buildings located along the coast. The sea advances destroyed beaches and have promoted an accelerated level of erosion, changing the

  12. Modeling the influence of climate change on the mass balance of polychlorinated biphenyls in the Adriatic Sea.

    PubMed

    Lamon, Lara; MacLeod, Matthew; Marcomini, Antonio; Hungerbühler, Konrad

    2012-05-01

    Climate forcing is forecasted to influence the Adriatic Sea region in a variety of ways, including increasing temperature, and affecting wind speeds, marine currents, precipitation and water salinity. The Adriatic Sea is intensively developed with agriculture, industry, and port activities that introduce pollutants to the environment. Here, we developed and applied a Level III fugacity model for the Adriatic Sea to estimate the current mass balance of polychlorinated biphenyls in the Sea, and to examine the effects of a climate change scenario on the distribution of these pollutants. The model's performance was evaluated for three PCB congeners against measured concentrations in the region using environmental parameters estimated from the 20th century climate scenario described in the Special Report on Emission Scenarios (SRES) by the IPCC, and using Monte Carlo uncertainty analysis. We find that modeled fugacities of PCBs in air, water and sediment of the Adriatic are in good agreement with observations. The model indicates that PCBs in the Adriatic Sea are closely coupled with the atmosphere, which acts as a net source to the water column. We used model experiments to assess the influence of changes in temperature, wind speed, precipitation, marine currents, particulate organic carbon and air inflow concentrations forecast in the IPCC A1B climate change scenario on the mass balance of PCBs in the Sea. Assuming an identical PCBs' emission profile (e.g. use pattern, treatment/disposal of stockpiles, mode of entry), modeled fugacities of PCBs in the Adriatic Sea under the A1B climate scenario are higher because higher temperatures reduce the fugacity capacity of air, water and sediments, and because diffusive sources to the air are stronger.

  13. Response of salt marsh and mangrove wetlands to changes in atmospheric CO2, climate, and sea-level

    USGS Publications Warehouse

    Mckee, Karen L.; Rogers, Kerrylee; Saintilan, Neil; Middleton, Beth A.

    2012-01-01

    Coastal salt marsh and mangrove ecosystems are particularly vulnerable to changes in atmospheric CO2 concentrations and associated climate and climate-induced changes. We provide a review of the literature detailing theoretical predictions and observed responses of coastal wetlands to a range of climate change stressors, including CO2, temperature, rainfall, and sea-level rise. This review incorporates a discussion of key processes controlling responses in different settings and thresholds of resilience derived from experimental and observational studies. We specifically consider the potential and observed effects on salt marsh and mangrove vegetation of changes in (1) elevated [CO2] on physiology, growth, and distribution; (2) temperature on distribution and diversity; (3) rainfall and salinity regimes on growth and competitive interactions; and (4) sea level on geomorphological, hydrological, and biological processes.

  14. Declining Sea Ice Extent Links Early Winter Climate to Changing Arctic Lakes

    NASA Astrophysics Data System (ADS)

    Alexeev, V. A.; Arp, C. D.; Jones, B. M.; Cai, L.

    2015-12-01

    Lakes on the Alaskan North Slope regulate surface energy balance and interactions with permafrost as well as providing important habitat. Winter lake ice regimes (floating-ice or bedfast-ice conditions) determine whether lakes develop and maintain taliks and can support overwintering fish habitat. Lake ice thickness is a key variable determining whether a lake has a bedfast or floating-ice regime. Recent observations suggest a trend towards more lakes with floating-ice conditions due to thinner ice growth, but the broader scale associated climate conditions driving these regime shift are less certain. This study finds that the changing arctic summer/fall sea ice conditions might be affecting lake ice thickness on the North Slope. Late ocean freeze-up near the Alaskan coast leads to warmer weather and more snowfall in the early winter. Warmer early winters and thicker snowpack result in thinner lake ice the following winter thus potentially developing more ice-floating lakes before the start of the summer. Experiments with a regional atmospheric model WRF for two years with very different sea ice conditions indicate that the extent of open water next to the North Slope is a crucial factor for developing thicker snowpack, also warmer air temperature in early winter.

  15. Modelling the increased frequency of extreme sea levels in the Ganges-Brahmaputra-Meghna delta due to sea level rise and other effects of climate change.

    PubMed

    Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A

    2015-07-01

    Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end

  16. Modelling the increased frequency of extreme sea levels in the Ganges-Brahmaputra-Meghna delta due to sea level rise and other effects of climate change.

    PubMed

    Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A

    2015-07-01

    Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end

  17. Climate and sea level changes and the role of shelf morphology in recording in Sibuyan Sea Basin, Philippines during the last 14 kyBP

    NASA Astrophysics Data System (ADS)

    Lloren, R. B.; Siringan, F. P.

    2014-12-01

    In this study, we reconstruct changes in precipitation using geochemical and grain size proxies and we look at how shelf morphology can influence the nature of sedimentary record of climate and oceanographic events. A 9.6m long sediment core from Sibuyan Sea basin within the internal seas of the Philippines, was raised from a water depth of 1660m. It was analyzed using an XRF core scanner at 1 cm resolution. Grain size was determined using a laser particle analyzer. Thirteen AMS radiocarbon dates from bulk organics provide age control spanning back to 14 kyBP. Overall, the trends of precipitation proxies Ti, Al and Al/Ti follow the 10o N insolation curve. A 1.4 ky periodicity rides on this general trend. But a stepwise decrease of these precipitation proxies occur at about 9ka and 4ka. The former correpond to the melt water pulse 1-c rapid sea level rise of about 15m while the latter correlates time-wise to a period of aridification. The Younger Dryas period, ca. 12.9-11.6 ka, another known dry period, does not show a shift or decrease in sediment input. Similarly, MWP -1B does no register a distinct signal in the core. The insensitivity of the core in reflecting the older climate and sea level events is attributed to the steep morphology of the sea floor where shoreline translations took place during the earlier sea level events; with a steeper sea floor, sediment sequestration near the shoreline will be low and therefore the basin will not feel much change in sediment input. For the younger climate and sea level events, the shoreline positions were already adjacent to sea floor with relatively gentler gradient where sediment sequestration is greater and where a sea level rise of a certain magnitude will translate the shoreline much farther.

  18. Sea Level Rise and Climate Change Effects on Marsh Plants Spartina Alterniflora and Typha Angustifolia Using Mesocosms

    EPA Science Inventory

    A four month experiment using greenhouse mesocosms was conducted to analyze the effect of sea level rise and climate change on salt marsh plants Spartina alterniflora (cordgrass) and Typha angustifolia (narrow-leaved cattail). Our goal was to examine the effects of three differen...

  19. Beyond just sea-level rise: Considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change

    USGS Publications Warehouse

    Osland, Michael J.; Enwright, Nicholas M.; Day, Richard H.; Gabler, Christopher A.; Stagg, Camille L.; Grace, James B.

    2016-01-01

    Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate-change related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea-level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands.

  20. Effects of climate change and agricultural adaptation on nutrient loading from Finnish catchments to the Baltic Sea.

    PubMed

    Huttunen, Inese; Lehtonen, Heikki; Huttunen, Markus; Piirainen, Vanamo; Korppoo, Marie; Veijalainen, Noora; Viitasalo, Markku; Vehviläinen, Bertel

    2015-10-01

    Climate change is expected to increase annual and especially winter runoff, shorten the snow cover period and therefore increase both nutrient leaching from agricultural areas and natural background leaching in the Baltic Sea catchment. We estimated the effects of climate change and possible future scenarios of agricultural changes on the phosphorus and nitrogen loading to the Baltic Sea from Finnish catchments. In the agricultural scenarios we assumed that the prices of agricultural products are among the primary drivers in the adaptation to climate change, as they affect the level of fertilization and the production intensity and volume and, hence, the modeled changes in gross nutrient loading from agricultural land. Optimal adaptation may increase production while supporting appropriate use of fertilization, resulting in low nutrient balance in the fields. However, a less optimal adaptation may result in higher nutrient balance and increased leaching. The changes in nutrient loading to the Baltic Sea were predicted by taking into account the agricultural scenarios in a nutrient loading model for Finnish catchments (VEMALA), which simulates runoff, nutrient processes, leaching and transport on land, in rivers and in lakes. We thus integrated the effects of climate change in the agricultural sector, nutrient loading in fields, natural background loading, hydrology and nutrient transport and retention processes.

  1. Beyond just sea-level rise: considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change.

    PubMed

    Osland, Michael J; Enwright, Nicholas M; Day, Richard H; Gabler, Christopher A; Stagg, Camille L; Grace, James B

    2016-01-01

    Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate change-related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea-level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands. PMID:26342186

  2. Beyond just sea-level rise: considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change.

    PubMed

    Osland, Michael J; Enwright, Nicholas M; Day, Richard H; Gabler, Christopher A; Stagg, Camille L; Grace, James B

    2016-01-01

    Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate change-related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea-level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands.

  3. Impact of climate change on the northwestern Mediterranean Sea pelagic planktonic ecosystem and associated carbon cycle

    NASA Astrophysics Data System (ADS)

    Herrmann, Marine; Estournel, Claude; Adloff, Fanny; Diaz, Frédéric

    2014-09-01

    The northwestern Mediterranean Sea (NWMS) is biologically one of the most productive Mediterranean regions. NWMS pelagic planktonic ecosystem is strongly influenced by hydrodynamics, in particular by deep convection that could significantly weaken under the influence of climate change. Here we investigate the response of this ecosystem and associated carbon cycle to the long-term evolution of oceanic and atmospheric circulations. For that we developed a tridimensional coupled physical-biogeochemical model and performed two groups of annual simulations under the climate conditions of respectively the 20th and the end of 21st centuries. Our results suggest that the evolution of oceanic and atmospheric circulations does not modify the NWMS pelagic planktonic ecosystem and associated carbon cycle at a first order. However, differences mainly induced by the deep convection weakening and the surface warming are obtained at a second order. The spring bloom occurs 1 month earlier. Resulting from the decrease in nutrients availability, the bottom up control of phytoplankton development and bacteria growth by the nitrogen and phosphorus availability strengthens and the microbial loop intensifies as the small-sized plankton biomass increases. Carbon net fixation and deep export do not change significantly. The choice of the biogeochemical initial and boundary conditions does not change the representation of the ecosystem seasonal cycle, but the associated uncertainty range can be one order of magnitude larger than the predicted interannual and long-term variabilities. The uncertainty range of long-term trends associated with the physical forcing (hydrological, atmospheric, hydrodynamical, and socioeconomic) is much smaller (<10%).

  4. Centennial-scale climate change from decadally-paced explosive volcanism: a coupled sea ice-ocean mechanism

    NASA Astrophysics Data System (ADS)

    Zhong, Y.; Miller, G. H.; Otto-Bliesner, B. L.; Holland, M. M.; Bailey, D. A.; Schneider, D. P.; Geirsdottir, A.

    2011-12-01

    Northern Hemisphere summer cooling through the Holocene is largely driven by the steady decrease in summer insolation tied to the precession of the equinoxes. However, centennial-scale climate departures, such as the Little Ice Age, must be caused by other forcings, most likely explosive volcanism and changes in solar irradiance. Stratospheric volcanic aerosols have the stronger forcing, but their short residence time likely precludes a lasting climate impact from a single eruption. Decadally paced explosive volcanism may produce a greater climate impact because the long response time of ocean surface waters allows for a cumulative decrease in sea-surface temperatures that exceeds that of any single eruption. Here we use a global climate model to evaluate the potential long-term climate impacts from four decadally paced large tropical eruptions. Direct forcing results in a rapid expansion of Arctic Ocean sea ice that persists throughout the eruption period. The expanded sea ice increases the flux of sea ice exported to the northern North Atlantic long enough that it reduces the convective warming of surface waters in the subpolar North Atlantic. In two of our four simulations the cooler surface waters being advected into the Arctic Ocean reduced the rate of basal sea-ice melt in the Atlantic sector of the Arctic Ocean, allowing sea ice to remain in an expanded state for > 100 model years after volcanic aerosols were removed from the stratosphere. In these simulations the coupled sea ice-ocean mechanism maintains the strong positive feedbacks of an expanded Arctic Ocean sea ice cover, allowing the initial cooling related to the direct effect of volcanic aerosols to be perpetuated, potentially resulting in a centennial-scale or longer change of state in Arctic climate. The fact that the sea ice-ocean mechanism was not established in two of our four simulations suggests that a long-term sea ice response to volcanic forcing is sensitive to the stability of the seawater

  5. Modeling marine protected areas for threatened eiders in a climatically changing Bering Sea.

    PubMed

    Lovvorn, James R; Grebmeier, Jacqueline M; Cooper, Lee W; Bump, Joseph K; Richman, Samantha E

    2009-09-01

    Delineating protected areas for sensitive species is a growing challenge as changing climate alters the geographic pattern of habitats as well as human responses to those shifts. When human impacts are expected within projected ranges of threatened species, there is often demand to demarcate the minimum habitat required to ensure the species' persistence. Because diminished or wide-ranging populations may not occupy all viable (and needed) habitat at once, one must identify thresholds of resources that will support the species even in unoccupied areas. Long-term data on the shifting mosaic of critical resources may indicate ranges of future variability. We addressed these issues for the Spectacled Eider (Somateria fischeri), a federally threatened species that winters in pack ice of the Bering Sea. Changing climate has decreased ice cover and severely reduced the eiders' benthic prey and has increased prospects for expansion of bottom trawling that may further affect prey communities. To assess long-term changes in habitats that will support eiders, we linked data on benthic prey, sea ice, and weather from 1970 to 2001 with a spatially explicit simulation model of eider energy balance that integrated field, laboratory, and remote-sensing studies. Areas estimated to have prey densities adequate for eiders in 1970-1974 did not include most areas that were viable 20 years later (1993-1994). Unless the entire area with adequate prey in 1993-1994 had been protected, the much reduced viable area in 1999-2001 might well have been excluded. During long non-foraging periods (as at night), eiders can save much energy by resting on ice vs. floating on water; thus, loss of ice cover in the future might substantially decrease the area in which prey densities are adequate to offset the eiders' energy needs. For wide-ranging benthivores such as eiders, our results emphasize that fixed protected areas based on current conditions can be too small or inflexible to subsume long

  6. Impact of climate change and sea level rise on a coastal aquifer, Central Vietnam

    NASA Astrophysics Data System (ADS)

    Beyen, Ine; Batelaan, Okke; Thanh Tam, Vu

    2013-04-01

    The Gio Linh district in the Quang Tri province, Central Vietnam has, like many other coastal areas in the world, to deal with negative impacts of Global Climate Change (GCC) and sea level rise (SLR). This research aims at investigating the impact of GCC/SLR and designing an adaptive water use plan till the year 2030 for the local residents of the Gio Linh district. This coastal plain covers an area of about 450 km2 and is situated between the rivers Ben Hai in the North and Thach Han in the South. The elevation varies from 0.5 m at the seaside in the East to 19.5 m further inland. During the rainy season from August to April the precipitation is on average 2000 to 2700 mm. GCC/SLR scenarios are built and assessed for estimating the changes in hydrometeorological conditions of the study area. Depending on the level of gas emission the sea level is expected to rise 7-9 cm by 2020 and around 11-14 cm by 2030 for low to high gas emission respectively. The salt-freshwater interface is expected to experience an inland shift due to SLR, affecting the amount of exploitable groundwater for drinking and irrigation water production. Drinking water production mainly comes from shallow aquifers in unconsolidated Quarternary coastal formations. A SEAWAT groundwater model will be built to study the effects on the groundwater system. Data from meteorological stations over a period of about 30 years and data from 63 boreholes in and around the Gio Linh district are available. Historical production records of an operational groundwater production well-field are available to be used for validation of the model. Finally, to achieve a sustainable integrated water resources management in the Gio Linh district different adaptive scenarios will be developed.

  7. Estuarine Response to River Flow and Sea-Level Rise under Future Climate Change and Human Development

    SciTech Connect

    Yang, Zhaoqing; Wang, Taiping; Voisin, Nathalie; Copping, Andrea E.

    2015-04-01

    Understanding the response of river flow and estuarine hydrodynamics to climate change, land-use/land-cover change (LULC), and sea-level rise is essential to managing water resources and stress on living organisms under these changing conditions. This paper presents a modeling study using a watershed hydrology model and an estuarine hydrodynamic model, in a one-way coupling, to investigate the estuarine hydrodynamic response to sea-level rise and change in river flow due to the effect of future climate and LULC changes in the Snohomish River estuary, Washington, USA. A set of hydrodynamic variables, including salinity intrusion points, average water depth, and salinity of the inundated area, were used to quantify the estuarine response to river flow and sea-level rise. Model results suggest that salinity intrusion points in the Snohomish River estuary and the average salinity of the inundated areas are a nonlinear function of river flow, although the average water depth in the inundated area is approximately linear with river flow. Future climate changes will shift salinity intrusion points further upstream under low flow conditions and further downstream under high flow conditions. In contrast, under the future LULC change scenario, the salinity intrusion point will shift downstream under both low and high flow conditions, compared to present conditions. The model results also suggest that the average water depth in the inundated areas increases linearly with sea-level rise but at a slower rate, and the average salinity in the inundated areas increases linearly with sea-level rise; however, the response of salinity intrusion points in the river to sea-level rise is strongly nonlinear.

  8. Adapting to rates versus amounts of climate change: a case of adaptation to sea-level rise

    NASA Astrophysics Data System (ADS)

    Shayegh, Soheil; Moreno-Cruz, Juan; Caldeira, Ken

    2016-10-01

    Adaptation is the process of adjusting to climate change in order to moderate harm or exploit beneficial opportunities associated with it. Most adaptation strategies are designed to adjust to a new climate state. However, despite our best efforts to curtail greenhouse gas emissions, climate is likely to continue changing far into the future. Here, we show how considering rates of change affects the projected optimal adaptation strategy. We ground our discussion with an example of optimal investment in the face of continued sea-level rise, presenting a quantitative model that illustrates the interplay among physical and economic factors governing coastal development decisions such as rate of sea-level rise, land slope, discount rate, and depreciation rate. This model shows that the determination of optimal investment strategies depends on taking into account future rates of sea-level rise, as well as social and political constraints. This general approach also applies to the development of improved strategies to adapt to ongoing trends in temperature, precipitation, and other climate variables. Adaptation to some amount of change instead of adaptation to ongoing rates of change may produce inaccurate estimates of damages to the social systems and their ability to respond to external pressures.

  9. Impacts of sea level rise and climate change on coastal plant species in the central California coast.

    PubMed

    Garner, Kendra L; Chang, Michelle Y; Fulda, Matthew T; Berlin, Jonathan A; Freed, Rachel E; Soo-Hoo, Melissa M; Revell, Dave L; Ikegami, Makihiko; Flint, Lorraine E; Flint, Alan L; Kendall, Bruce E

    2015-01-01

    Local increases in sea level caused by global climate change pose a significant threat to the persistence of many coastal plant species through exacerbating inundation, flooding, and erosion. In addition to sea level rise (SLR), climate changes in the form of air temperature and precipitation regimes will also alter habitats of coastal plant species. Although numerous studies have analyzed the effect of climate change on future habitats through species distribution models (SDMs), none have incorporated the threat of exposure to SLR. We developed a model that quantified the effect of both SLR and climate change on habitat for 88 rare coastal plant species in San Luis Obispo, Santa Barbara, and Ventura Counties, California, USA (an area of 23,948 km(2)). Our SLR model projects that by the year 2100, 60 of the 88 species will be threatened by SLR. We found that the probability of being threatened by SLR strongly correlates with a species' area, elevation, and distance from the coast, and that 10 species could lose their entire current habitat in the study region. We modeled the habitat suitability of these 10 species under future climate using a species distribution model (SDM). Our SDM projects that 4 of the 10 species will lose all suitable current habitats in the region as a result of climate change. While SLR accounts for up to 9.2 km(2) loss in habitat, climate change accounts for habitat suitability changes ranging from a loss of 1,439 km(2) for one species to a gain of 9,795 km(2) for another species. For three species, SLR is projected to reduce future suitable area by as much as 28% of total area. This suggests that while SLR poses a higher risk, climate changes in precipitation and air temperature represents a lesser known but potentially larger risk and a small cumulative effect from both. PMID:26020011

  10. Impacts of sea level rise and climate change on coastal plant species in the central California coast.

    PubMed

    Garner, Kendra L; Chang, Michelle Y; Fulda, Matthew T; Berlin, Jonathan A; Freed, Rachel E; Soo-Hoo, Melissa M; Revell, Dave L; Ikegami, Makihiko; Flint, Lorraine E; Flint, Alan L; Kendall, Bruce E

    2015-01-01

    Local increases in sea level caused by global climate change pose a significant threat to the persistence of many coastal plant species through exacerbating inundation, flooding, and erosion. In addition to sea level rise (SLR), climate changes in the form of air temperature and precipitation regimes will also alter habitats of coastal plant species. Although numerous studies have analyzed the effect of climate change on future habitats through species distribution models (SDMs), none have incorporated the threat of exposure to SLR. We developed a model that quantified the effect of both SLR and climate change on habitat for 88 rare coastal plant species in San Luis Obispo, Santa Barbara, and Ventura Counties, California, USA (an area of 23,948 km(2)). Our SLR model projects that by the year 2100, 60 of the 88 species will be threatened by SLR. We found that the probability of being threatened by SLR strongly correlates with a species' area, elevation, and distance from the coast, and that 10 species could lose their entire current habitat in the study region. We modeled the habitat suitability of these 10 species under future climate using a species distribution model (SDM). Our SDM projects that 4 of the 10 species will lose all suitable current habitats in the region as a result of climate change. While SLR accounts for up to 9.2 km(2) loss in habitat, climate change accounts for habitat suitability changes ranging from a loss of 1,439 km(2) for one species to a gain of 9,795 km(2) for another species. For three species, SLR is projected to reduce future suitable area by as much as 28% of total area. This suggests that while SLR poses a higher risk, climate changes in precipitation and air temperature represents a lesser known but potentially larger risk and a small cumulative effect from both.

  11. Impacts of sea level rise and climate change on coastal plant species in the central California coast

    PubMed Central

    Chang, Michelle Y.; Fulda, Matthew T.; Berlin, Jonathan A.; Freed, Rachel E.; Soo-Hoo, Melissa M.; Revell, Dave L.; Ikegami, Makihiko; Flint, Lorraine E.; Flint, Alan L.; Kendall, Bruce E.

    2015-01-01

    Local increases in sea level caused by global climate change pose a significant threat to the persistence of many coastal plant species through exacerbating inundation, flooding, and erosion. In addition to sea level rise (SLR), climate changes in the form of air temperature and precipitation regimes will also alter habitats of coastal plant species. Although numerous studies have analyzed the effect of climate change on future habitats through species distribution models (SDMs), none have incorporated the threat of exposure to SLR. We developed a model that quantified the effect of both SLR and climate change on habitat for 88 rare coastal plant species in San Luis Obispo, Santa Barbara, and Ventura Counties, California, USA (an area of 23,948 km2). Our SLR model projects that by the year 2100, 60 of the 88 species will be threatened by SLR. We found that the probability of being threatened by SLR strongly correlates with a species’ area, elevation, and distance from the coast, and that 10 species could lose their entire current habitat in the study region. We modeled the habitat suitability of these 10 species under future climate using a species distribution model (SDM). Our SDM projects that 4 of the 10 species will lose all suitable current habitats in the region as a result of climate change. While SLR accounts for up to 9.2 km2 loss in habitat, climate change accounts for habitat suitability changes ranging from a loss of 1,439 km2 for one species to a gain of 9,795 km2 for another species. For three species, SLR is projected to reduce future suitable area by as much as 28% of total area. This suggests that while SLR poses a higher risk, climate changes in precipitation and air temperature represents a lesser known but potentially larger risk and a small cumulative effect from both. PMID:26020011

  12. Sea level rise along Malaysian coasts due to the climate change

    NASA Astrophysics Data System (ADS)

    Luu, Quang-Hung; Tkalich, Pavel; Tay, Tzewei

    2015-04-01

    Malaysia consists of two major parts, a mainland on the Peninsular Malaysia and the East Malaysia on the Borneo Island. Their surrounding waters connect the Andaman Sea located northeast of the Indian Ocean to the Celebes Sea in the western tropical Pacific Ocean through the southern East Sea of Vietnam/South China Sea. As a result, inter-annual sea level in the Malaysian waters is governed by various regional phenomena associated with the adjacent parts of the Indian and Pacific Oceans. We estimated sea level rise (SLR) rate in the domain using tide gauge records often being gappy. To reconstruct the missing data, two methods are used: (i) correlating sea level with climate indices El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD), and (ii) filling the gap using records of neighboring tide gauges. Latest vertical land movements have been acquired to derive geocentric SLR rates. Around the Peninsular Malaysia, geocentric SLR rates in waters of Malacca Strait and eastern Peninsular Malaysia during 1986-2011 are found to be 3.9±3.3 mm/year and 4.2 ± 2.5 mm/year, respectively; while in the East Malaysia waters the rate during 1988-2011 is 6.3 ± 4.0 mm/year. These rates are arguably higher than global tendency for the same periods. For the overlapping period 1993-2011, the rates are consistent with those obtained using satellite altimetry.

  13. Climate Change

    NASA Astrophysics Data System (ADS)

    Cowie, Jonathan

    2001-05-01

    In recent years climate change has become recognised as the foremost environmental problem of the twenty-first century. Not only will climate change potentially affect the multibillion dollar energy strategies of countries worldwide, but it also could seriously affect many species, including our own. A fascinating introduction to the subject, this textbook provides a broad review of past, present and likely future climate change from the viewpoints of biology, ecology and human ecology. It will be of interest to a wide range of people, from students in the life sciences who need a brief overview of the basics of climate science, to atmospheric science, geography, and environmental science students who need to understand the biological and human ecological implications of climate change. It will also be a valuable reference for those involved in environmental monitoring, conservation, policy-making and policy lobbying. The first book to cover not only the human impacts on climate, but how climate change will affect humans and the species that we rely on Written in an accessible style, with specialist terms used only when necessary and thoroughly explained The author has years of experience conveying the views of biological science learned societies to policy-makers

  14. Polar Climate: Arctic sea ice

    USGS Publications Warehouse

    Stone, R.S.; Douglas, David C.; Belchansky, G.I.; Drobot, S.D.

    2005-01-01

    Recent decreases in snow and sea ice cover in the high northern latitudes are among the most notable indicators of climate change. Northern Hemisphere sea ice extent for the year as a whole was the third lowest on record dating back to 1973, behind 1995 (lowest) and 1990 (second lowest; Hadley Center–NCEP). September sea ice extent, which is at the end of the summer melt season and is typically the month with the lowest sea ice extent of the year, has decreased by about 19% since the late 1970s (Fig. 5.2), with a record minimum observed in 2002 (Serreze et al. 2003). A record low extent also occurred in spring (Chapman 2005, personal communication), and 2004 marked the third consecutive year of anomalously extreme sea ice retreat in the Arctic (Stroeve et al. 2005). Some model simulations indicate that ice-free summers will occur in the Arctic by the year 2070 (ACIA 2004).

  15. Sea level change

    SciTech Connect

    Meier, M.F.

    1996-12-31

    The IPCC (Intergovernmental Panel on Climate Change) 1995 Scientific Assessment, Chapter 7. Sea Level Change, presents a modest revision of the similar chapter in the 1990 Assessment. Principal conclusions on observed sea-level change and the principal terms in the sea-level equation (ocean thermal expansion, glaciers, ice sheets, and land hydrology), including our knowledge of the present-day (defined as the 20th Century) components of sea-level rise, and projections of these for the future, are presented here. Some of the interesting glaciological problems which are involved in these studies are discussed in more detail. The emphasis here is on trends over decades to a century, not on shorter variations nor on those of the geologic past. Unfortunately, some of the IPCC projections had not been agreed at the time of writing of this paper, and these projections will not be given here. 15 refs., 2 figs.

  16. A chronology of alluvial fan response to Late Quaternary sea level and climate change, Crete

    NASA Astrophysics Data System (ADS)

    Pope, Richard J. J.; Candy, Ian; Skourtsos, Emmanuel

    2016-09-01

    To better understand how fluvial systems respond to late Quaternary climatic forcing OSL and U-series dating was applied to stratigraphically significant sedimentary units within a small (<6.5 km2) alluvial fan system (the Sphakia fan) in southwest Crete. The resultant chronology (comprising 32 OSL and U-series ages) makes Sphakia fan one of the best dated systems in the Mediterranean and suggests that Cretan fans responded to climate in two ways. First, during the transitions between Marine Isotope Stage (MIS) 5a/4 and MIS 2/1 Sphakia fan was characterised by significant entrenchment and distal shift in the zone of deposition. It is proposed that the phases of entrenchment were driven by sea level induced base level fall during MIS 5a/4 and landscape stabilisation during the onset of the current interglacial (MIS 2/1). Second, with the exception of these two entrenchment episodes fan alluviation occurred across the entire last interglacial/glacial cycle in all climatic settings i.e. interglacials, interstadials and stadials. It is likely that the topographic setting of the catchment supplying sediment to Sphakia fan maintained high sediment transfer rates during most climatic settings enabling fan aggradation to occur except during major climatic driven transitions i.e. major sea level fall and postglacial vegetation development.

  17. Cuba confronts climate change.

    PubMed

    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. Cuba confronts climate change.

    PubMed

    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. PMID:26027581

  19. Climate change adaptation under uncertainty in the developing world: A case study of sea level rise in Kiribati

    NASA Astrophysics Data System (ADS)

    Donner, S. D.; Webber, S.

    2011-12-01

    Climate change is expected to have the greatest impact in parts of the developing world. At the 2010 meeting of U.N. Framework Convention on Climate Change in Cancun, industrialized countries agreed in principle to provide US$100 billion per year by 2020 to assist the developing world respond to climate change. This "Green Climate Fund" is a critical step towards addressing the challenge of climate change. However, the policy and discourse on supporting adaptation in the developing world remains highly idealized. For example, the efficacy of "no regrets" adaptation efforts or "mainstreaming" adaptation into decision-making are rarely evaluated in the real world. In this presentation, I will discuss the gap between adaptation theory and practice using a multi-year case study of the cultural, social and scientific obstacles to adapting to sea level rise in the Pacific atoll nation of Kiribati. Our field research reveals how scientific and institutional uncertainty can limit international efforts to fund adaptation and lead to spiraling costs. Scientific uncertainty about hyper-local impacts of sea level rise, though irreducible, can at times limit decision-making about adaptation measures, contrary to the notion that "good" decision-making practices can incorporate scientific uncertainty. Efforts to improve institutional capacity must be done carefully, or they risk inadvertently slowing the implementation of adaptation measures and increasing the likelihood of "mal"-adaptation.

  20. Climate change-related regime shifts have altered spatial synchrony of plankton dynamics in the North Sea.

    PubMed

    Defriez, Emma J; Sheppard, Lawrence W; Reid, Philip C; Reuman, Daniel C

    2016-06-01

    During the 1980s, the North Sea plankton community underwent a well-documented ecosystem regime shift, including both spatial changes (northward species range shifts) and temporal changes (increases in the total abundances of warmer water species). This regime shift has been attributed to climate change. Plankton provide a link between climate and higher trophic-level organisms, which can forage on large spatial and temporal scales. It is therefore important to understand not only whether climate change affects purely spatial or temporal aspects of plankton dynamics, but also whether it affects spatiotemporal aspects such as metapopulation synchrony. If plankton synchrony is altered, higher trophic-level feeding patterns may be modified. A second motivation for investigating changes in synchrony is that the possibility of such alterations has been examined for few organisms, in spite of the fact that synchrony is ubiquitous and of major importance in ecology. This study uses correlation coefficients and spectral analysis to investigate whether synchrony changed between the periods 1959-1980 and 1989-2010. Twenty-three plankton taxa, sea surface temperature (SST), and wind speed were examined. Results revealed that synchrony in SST and plankton was altered. Changes were idiosyncratic, and were not explained by changes in abundance. Changes in the synchrony of Calanus helgolandicus and Para-pseudocalanus spp appeared to be driven by changes in SST synchrony. This study is one of few to document alterations of synchrony and climate-change impacts on synchrony. We discuss why climate-change impacts on synchrony may well be more common and consequential than previously recognized. PMID:26810148

  1. Climate change-related regime shifts have altered spatial synchrony of plankton dynamics in the North Sea.

    PubMed

    Defriez, Emma J; Sheppard, Lawrence W; Reid, Philip C; Reuman, Daniel C

    2016-06-01

    During the 1980s, the North Sea plankton community underwent a well-documented ecosystem regime shift, including both spatial changes (northward species range shifts) and temporal changes (increases in the total abundances of warmer water species). This regime shift has been attributed to climate change. Plankton provide a link between climate and higher trophic-level organisms, which can forage on large spatial and temporal scales. It is therefore important to understand not only whether climate change affects purely spatial or temporal aspects of plankton dynamics, but also whether it affects spatiotemporal aspects such as metapopulation synchrony. If plankton synchrony is altered, higher trophic-level feeding patterns may be modified. A second motivation for investigating changes in synchrony is that the possibility of such alterations has been examined for few organisms, in spite of the fact that synchrony is ubiquitous and of major importance in ecology. This study uses correlation coefficients and spectral analysis to investigate whether synchrony changed between the periods 1959-1980 and 1989-2010. Twenty-three plankton taxa, sea surface temperature (SST), and wind speed were examined. Results revealed that synchrony in SST and plankton was altered. Changes were idiosyncratic, and were not explained by changes in abundance. Changes in the synchrony of Calanus helgolandicus and Para-pseudocalanus spp appeared to be driven by changes in SST synchrony. This study is one of few to document alterations of synchrony and climate-change impacts on synchrony. We discuss why climate-change impacts on synchrony may well be more common and consequential than previously recognized.

  2. Climate change impacts on marine water quality: The case study of the Northern Adriatic sea.

    PubMed

    Rizzi, J; Torresan, S; Critto, A; Zabeo, A; Brigolin, D; Carniel, S; Pastres, R; Marcomini, A

    2016-01-30

    Climate change is posing additional pressures on coastal ecosystems due to variations in water biogeochemical and physico-chemical parameters (e.g., pH, salinity) leading to aquatic ecosystem degradation. With the main aim of analyzing the potential impacts of climate change on marine water quality, a Regional Risk Assessment methodology was developed and applied to coastal marine waters of the North Adriatic. It integrates the outputs of regional biogeochemical and physico-chemical models considering future climate change scenarios (i.e., years 2070 and 2100) with site-specific environmental and socio-economic indicators. Results showed that salinity and temperature will be the main drivers of changes, together with macronutrients, especially in the area of the Po' river delta. The final outputs are exposure, susceptibility and risk maps supporting the communication of the potential consequences of climate change on water quality to decision makers and stakeholders and provide a basis for the definition of adaptation and management strategies.

  3. Loggerhead sea turtle environmental sex determination: implications of moisture and temperature for climate change based predictions for species survival.

    PubMed

    Wyneken, Jeanette; Lolavar, Alexandra

    2015-05-01

    It has been proposed that because marine turtles have environmentally determined sex by incubation temperature, elevated temperatures might skew sex ratios to unsustainable levels, leading to extinction. Elevated temperatures may also reduce availability of suitable nesting sites via sea level rise. Increased tropical storm activity can directly affect nest site moisture, embryonic development, and the probability that nests will survive. Here, we question some of these assumptions and review the limits of sex ratio estimates. Sea turtles may be more resilient to climate change than previously thought, in part because of hitherto unappreciated mechanisms for coping with variable incubation conditions. PMID:25877336

  4. Loggerhead sea turtle environmental sex determination: implications of moisture and temperature for climate change based predictions for species survival.

    PubMed

    Wyneken, Jeanette; Lolavar, Alexandra

    2015-05-01

    It has been proposed that because marine turtles have environmentally determined sex by incubation temperature, elevated temperatures might skew sex ratios to unsustainable levels, leading to extinction. Elevated temperatures may also reduce availability of suitable nesting sites via sea level rise. Increased tropical storm activity can directly affect nest site moisture, embryonic development, and the probability that nests will survive. Here, we question some of these assumptions and review the limits of sex ratio estimates. Sea turtles may be more resilient to climate change than previously thought, in part because of hitherto unappreciated mechanisms for coping with variable incubation conditions.

  5. Models for fine-scale movements along growth faults associated with climate/sea level changes

    SciTech Connect

    Lowrie, A.

    1986-09-01

    Along the northern Gulf of Mexico, the deglaciation phase of a Pliocene-Pleistocene glacial cycle produced up to a tenfold increase in waters available for sediment transportation to continental margins. With lowered sea levels during glacial maxima, sedimentary pulses are deposited along the shelf break and on the slope. High-energy deposition promotes foundation instability. Growth faults then originate along the shelf break. Increased lithostatic pressure due to rapid deposition on underlying unconsolidated and semiconsolidated sediments, semiplastic salt, and marine clays promote flow that accelerates compaction, fluid migration, growth fault movements, and salt tectonics. Sedimentary depositional cycles of deca- and centenary-millennia are recorded throughout the Phanerozoic. Planetary orbital motions, controlling the amount of incoming solar radiation and lasting 20,000, 40,00, and 100,000 years, apparently cause these depositional cycles via climate/sea level fluctuations. When sea level is low, sediments are deposited about or beyond the shelf break. Increased lithostatic pressure promotes movement on the fault, deposition on the downthrown block, accelerated compaction of sediments, and fluid expulsion and migration. When sea level is high, sediment deposition is along the upper and middle shelf. Fault activity should be minimal or nil. Thus, the geologic episodes that record the greatest amount of downthrown block growth may also be punctuated by bursts of large drops in sea level. Onshore Louisiana production is usually greatest from maximum growth downthrown blocks.

  6. Climate change and control of the southeastern Bering Sea pelagic ecosystem

    NASA Astrophysics Data System (ADS)

    Hunt, George L., Jr.; Stabeno, Phyllis; Walters, Gary; Sinclair, Elizabeth; Brodeur, Richard D.; Napp, Jeffery M.; Bond, Nicholas A.

    2002-12-01

    provide forage. The OCH predicts that the ability of large predatory fish populations to sustain fishing pressure will vary between warm and cold regimes. The OCH points to the importance of the timing of ice retreat and water temperatures during the spring bloom for the productivity of zooplankton, and the degree and direction of coupling between zooplankton and forage fish. Forage fish (e.g., juvenile pollock, capelin, Pacific herring [ Clupea pallasii]) are key prey for adult pollock and other apex predators. In the southeastern Bering Sea, important changes in the biota since the mid-1970s include a marked increase in the biomass of large piscivorous fish and a concurrent decline in the biomass of forage fish, including age-1 walleye pollock, particularly over the southern portion of the shelf. Populations of northern fur seals ( Callorhinus ursinus) and seabirds such as kittiwakes ( Rissa spp.) at the Pribilof Islands have declined, most probably in response to a diminished prey base. The available evidence suggests that these changes are unlikely the result of a decrease in total annual new primary production, though the possibility of reduced post-bloom production during summer remains. An ecosystem approach to management of the Bering Sea and its fisheries is of great importance if all of the ecosystem components valued by society are to thrive. Cognizance of how climate regimes may alter relationships within this ecosystem will facilitate reaching that goal.

  7. The influence of climate change on the intensity of ice gouging at the Kara Sea bottom by hummocky formations

    NASA Astrophysics Data System (ADS)

    Ogorodov, Stanislav; Arkhipov, Vasily; Kokin, Osip; Natalia, Shabanova

    2016-04-01

    Sea ice as a zonal factor is an important passive and active relief-forming agent in the coastal-shelf zone of the Arctic and other freezing seas. The most dangerous process in relation to the hydrotechnical facilities is ice gouging - destructive mechanical impact of the ice of the ground, connected with the dynamics of the ice cover, formation of hummocks and stamukhas under the influence of hydrometeorologic factors and of the relief of the coastal-shelf zone. Underestimation of the ice gouging intensity can lead to damage of the engineering facilities, while excessive deepening increases the expenses of the construction. Finding the optimal variant and, by this, decreasing the risks of extreme situations is a relevant task of the science and practice. This task is complicated by the fact that the oil and gas infrastructure within the coastal and shelf areas of the freezing seas is currently being developed in the conditions of global climate change. In the present work, several results of the repeated sounding of bottom ice gouging microrelief within the area of the underwater pipeline crossing of the Baydaratskaya Bay, Kara Sea, are presented. Based on the results of the monitoring, as well as the analysis of literature sources and modeling it has been established that under the conditions of climate warming and sea ice reduction, the zone of the most intensive ice gouging is shifted landwards, on shallower water areas.

  8. The Isotopic Composition of Precipitation and of Groundwater Recharge in the Eastern Mediterranean Sea Area Under a Changing Climate: Considerations for the Evaluation of Paleo-Climate Conditions

    NASA Astrophysics Data System (ADS)

    Gat, J. R.

    2002-12-01

    Precipitation in the eastern Mediterranean Sea region is characterized by a singular isotopic composition with a large deuterium excess, which is the result of the strong temperature contrast between the European air masses and the Mediterranean waters during the winter months under the present climate regime. Under the semi-arid and arid conditions of the Middle East this input signal is further modified during the transition into the hydrological systems, due to the strong evaporative component in the water balance. The factors which determine the isotope composition of the precipitation in the eastern Mediterranean Sea area will be reviewed, starting from synoptic history of the air masses concerned, the air-sea interaction process at the source areas of the atmospheric moisture, the water balance in the air masses during their trajectory and the rain forming processes as well as the local conditions which result in the changes of the ISOTOPE TRANSFER FUNCTION (the ITF), i.e. the change of the isotope composition during the transition from the precipitation input to the related hydrological systems. The observed changes in the isotope composition of the local precipitation during 40 years of measurements as a function of rain amounts and drought periods will also be reported. Based on this information, an attempt will be made to estimate the expected changes in the isotope composition of the precipitation and of the ITF in this region as a function of the global climate changes and thus specify the reliability of the paleo-climatic reconstructions in the region.

  9. Interdisciplinary assessment of sea-level rise and climate change impacts on the lower Nile delta, Egypt.

    PubMed

    Sušnik, Janez; Vamvakeridou-Lyroudia, Lydia S; Baumert, Niklas; Kloos, Julia; Renaud, Fabrice G; La Jeunesse, Isabelle; Mabrouk, Badr; Savić, Dragan A; Kapelan, Zoran; Ludwig, Ralf; Fischer, Georg; Roson, Roberto; Zografos, Christos

    2015-01-15

    CLImate-induced changes on WAter and SECurity (CLIWASEC) was a cluster of three complementary EC-FP7 projects assessing climate-change impacts throughout the Mediterranean on: hydrological cycles (CLIMB - CLimate-Induced changes on the hydrology of Mediterranean Basins); water security (WASSERMed - Water Availability and Security in Southern EuRope and the Mediterranean) and human security connected with possible hydro-climatic conflicts (CLICO - CLImate change hydro-COnflicts and human security). The Nile delta case study was common between the projects. CLIWASEC created an integrated forum for modelling and monitoring to understand potential impacts across sectors. This paper summarises key results from an integrated assessment of potential challenges to water-related security issues, focusing on expected sea-level rise impacts by the middle of the century. We use this common focus to illustrate the added value of project clustering. CLIWASEC pursued multidisciplinary research by adopting a single research objective: sea-level rise related water security threats, resulting in a more holistic view of problems and potential solutions. In fragmenting research, policy-makers can fail to understand how multiple issues can materialize from one driver. By combining efforts, an integrated assessment of water security threats in the lower Nile is formulated, offering policy-makers a clearer picture of inter-related issues to society and environment. The main issues identified by each project (land subsidence, saline intrusion - CLIMB; water supply overexploitation, land loss - WASSERMed; employment and housing security - CLICO), are in fact related. Water overexploitation is exacerbating land subsidence and saline intrusion, impacting on employment and placing additional pressure on remaining agricultural land and the underdeveloped housing market. All these have wider implications for regional development. This richer understanding could be critical in making better

  10. Staggering Changes in Mediterranean Sea Surface Temperatures Coincide with Global Climate and Evolution Transitions during the Late Miocene - Pliocene

    NASA Astrophysics Data System (ADS)

    Tzanova, A.; Herbert, T.; Peterson, L.

    2012-12-01

    The Late Miocene warmer-than-modern Earth is a time of important transitions such as the C3/C4 photosynthesis transition, the appearance of the Sahara and the hominin evolution. The interconnections and drivers for climate and evolutionary change during this time, such as pCO2, albedo, vegetation and temperatures, are still speculative. The causal relationships can be better understood via paleoproxy records from sensitive to climate shifts areas such as the Mediterranean Sea. The Mediterranean Sea is a largely enclosed mid-latitude basin on the cusp of the subtropical climate zone formed after the closure of the Tethys. The enclosed nature of the Mediterranean Sea makes it sensitive to continental climate and shifts in climate zones with the advantage of resolution, preservation and detail usually reserved for marine records Here we present a continuous 30 kyr resolution, sea surface temperature (SST) record for the Mediterranean Sea (Late Miocene - Pliocene) from the well-dated, uplifted marine sequences of Monte dei Corvi in Northern Italy and Rosello in Sicily, Italy. The Late Miocene portion of the record is from the pelagic, uplifted Monte dei Corvi land section. The data from two organic paleothermometers UK'37 and TEX86, establish the Mediterranean Sea as notably warmer than present. SSTs were equivalent and even higher than the warmest parts of the modern ocean. For the oldest samples, ~ 12.9 Ma to ~8.1 Ma, UK'37 derived temperatures hovered close to 28oC and possibly even higher. A distinct cooling trend takes over starting at ~8.1 Ma and superimposed upon it are prominent, high variability, cold episodes lasting from ~7 Ma to 6 Ma. During these extreme episodes, reconstructed SSTs reach values comparable the modern eastern Mediterranean annual average SST of 19.5oC. The variability during this colder period is substantial, with temperature swings of as much as ~6-8 oC over 40 kyr. Continuous pelagic sedimentation resumes after the Messinian Salinity

  11. Influence of the ocean surface temperature and sea ice concentration on regional climate changes in Eurasia in recent decades

    NASA Astrophysics Data System (ADS)

    Semenov, V. A.; Mokhov, I. I.; Latif, M.

    2012-07-01

    Numerical experiments with the ECHAM5 atmospheric general circulation model have been performed in order to simulate the influence of changes in the ocean surface temperature (OST) and sea ice concentration (SIC) on climate characteristics in regions of Eurasia. The sensitivity of winter and summer climates to OST and SIC variations in 1998-2006 has been investigated and compared to those in 1968-1976. These two intervals correspond to the maximum and minimum of the Atlantic Long-Period Oscillation (ALO) index. Apart from the experiments on changes in the OST and SIC global fields, the experiments on OST anomalies only in the North Atlantic and SIC anomalies in the Arctic for the specified periods have been analyzed. It is established that temperature variations in Western Europe are explained by OST and SIC variations fairly well, whereas the warmings in Eastern Europe and Western Siberia, according to model experiments, are substantially (by a factor of 2-3) smaller than according to observational data. Winter changes in the temperature regime in continental regions are controlled mainly by atmospheric circulation anomalies. The model, on the whole, reproduces the empirical structure of changes in the winter field of surface pressure, in particular, the pressure decrease in the Caspian region; however, it substantially (approximately by three times) underestimates the range of changes. Summer temperature variations in the model are characterized by a higher statistical significance than winter ones. The analysis of the sensitivity of the climate in Western Europe to SIC variations alone in the Arctic is an important result of the experiments performed. It is established that the SIC decrease and a strong warming over the Barents Sea in the winter period leads to a cooling over vast regions of the northern part of Eurasia and increases the probability of anomalously cold January months by two times and more (for regions in Western Siberia). This effect is caused

  12. Understanding Sea Level Changes

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Today more than 100 million people worldwide live on coastlines within one meter of mean sea level; any short-term or long-term sea level change relative to vertical ground motion is of great societal and economic concern. As palm-environment and historical data have clearly indicated the existence and prevalence of such changes in the past, new scientific information regarding to the nature and causes and a prediction capability are of utmost importance for the future. The 10-20 cm global sea-level rise recorded over the last century has been broadly attributed to two effects: (1) the steric effect (thermal expansion and salinity-density compensation of sea water) following global climate; (2) mass-budget changes due to a number of competing geophysical and hydrological processes in the Earth-atmosphere-hydrosphere-cryosphere system, including water exchange from polar ice sheets and mountain glaciers to the ocean, atmospheric water vapor and land hydrological variations, and anthropogenic effects such as water impoundment in artificial reservoirs and extraction of groundwater, all superimposed on the vertical motions of solid Earth due to tectonics, rebound of the mantle from past and present deglaciation, and other local ground motions. As remote-sensing tools, a number of space geodetic measurements of sea surface topography (e.g., TOPEX/Poseidon, Jason), ice mass (e.g., ICESat), time-variable gravity (e.g. GRACE), and ground motions (SLR, VLBI, GPS, InSAR, Laser altimetry, etc.) become directly relevant. Understanding sea level changes "anywhere, anytime" in a well-defined terrestrial reference frame in terms of climate change and interactions among ice masses, oceans, and the solid Earth, and being able to predict them, emerge as one of the scientific challenges in the Solid Earth Science Working Group (SESWG, 2003) conclusions.

  13. Late Pliocene climate change 3.4-2.3 Ma: paleoceanographic record from the Yabuta Formation, Sea of Japan

    USGS Publications Warehouse

    Cronin, T. M.; Kitamura, A.; Ikeya, Noriyuki; Watanabe, M. E.; Kamiya, T.

    1994-01-01

    Late Pliocene paleoceanographic changes in the Sea of Japan between 3.4 and2.3 Ma were investigated through study of molluscs, diatoms, and ostracodes from the Yabuta Formation in Toyama Prefecture. The period 3.4-2.7 Ma was characterized by relatively high sea level and cool water benthic faunas. A progressive paleoceanographic shift towards colder oceanic conditions and lower sea level occurred beginning near 2.7 Ma, intenifying about 2.5 Ma, when important changes in ostracode and molluscan faunas occurred. Between 2.7 and 2.3 Ma, eight glacial events can be inferred based on drops in sea level of 50-60 m and increasing proportions of cold, shallow water ostracode species whose modern ecology and zoogeography indicate colder winter water temperatures (3-4??C). The glacial events between 2.5 and 2.3 Ma were the most intense. Preliminary interpretation of the faunal and oceanographic events of the Yabuta Formation suggests that they correspond to Northern Hemispheric cooling also known from North Atlantic deep-sea oxygen isotope, IRD, and planktic foraminiferal records, North Pacific diatom and radiolarian record, and the Chinese loess sequences. The eight glacial events may record a 41,000-yr obliquity cycle which characterized other late Pliocene climate proxy records. Inferred sea level drops near 2.5-2.3 Ma of about 50-60 m provide direct evidence from an ocean margin setting that supports deep sea oxygen isotopic evidence indicating major changes in global ice volume changes. ?? 1994.

  14. Regional ocean climate change scenarios for the Mediterranean Sea: assessing the uncertainties along the 21st century.

    NASA Astrophysics Data System (ADS)

    Somot, S.; Sevault, F.; Déqué, M.; Herrmann, M.; Dubois, C.; Aznar, R.; Padorno, E.; Alvarez-Fanjul, E.; Jorda, G.; Marcos, M.; Gomis, D.

    2012-04-01

    Following the IPCC scenarios (Gibelin and Déqué 2003, Giorgi 2006, IPCC 2007, Somot et al. 2008), the climate over the Mediterranean basin is foreseen to become warmer and drier during the 21st century. In terms of density, these two effects may have an opposite impact on the Mediterranean Sea surface waters (warmer and saltier), the winter ocean deep convection, the Mediterranean thermohaline circulation and the local steric sea level change. In this study, we use a suite of regional modeling techniques for the atmosphere-river-ocean regional climate system to assess the possible evolution of the Mediterranean Sea under a changing climate during the 21st century. Following the design described in Somot et al. (2006), seven 140-year long numerical experiments (1961-2100) have been run with a Mediterranean Sea regional ocean models (NEMOMED8) forced by varying the boundary conditions that is to say (i) the air-sea fluxes coming from 50-km regional climate models, (ii) the Mediterranean river runoff fluxes and Black Sea freshwater inputs and (iii) the near-Atlantic water characteristics. After the spin-up period, a control run (1961-2000) have been carried out for checking the model stability under present climate conditions. Then scenario runs (2001-2100) have been done under the SRES-B1, A1B and A2 scenario forcings. The regional ocean model has an horizontal resolution of about 10 km, the regional climate models have a resolution of about 50 km over the Mediterranean Sea. The ocean model is forced daily by momentum, water and heat fluxes at the surface. Explicit river runoff fluxes, Atlantic buffer zone and SST relaxation are the other forcings of the ocean models. For the control run, up to 2000, SST as well as greenhouse gas and aerosol concentration are imposed from observed values. The air-sea fluxes come from the RCM and the other forcings are climatologic. Then, beyond 2000, the SRES scenarios are prescribed and the various forcings are extracted from

  15. Arctic Sea Ice Thickness Distribution as an Indicator of Arctic Climate Change - Synthesis of Model Results and Observations

    NASA Astrophysics Data System (ADS)

    Maslowski, Wieslaw; Clement Kinney, Jaclyn; Jakacki, Jaromir; Osinski, Robert; Zwally, Jay

    2010-05-01

    The Arctic region is an integral part of the Earth's climate system through its influence on global surface energy and moisture fluxes and on atmospheric and oceanic circulation. Within the Arctic, its sea ice cover is possibly the most sensitive indicator of the polar amplified global warming and of the state of Arctic climate system as a whole. Hence changes in Arctic climate and the decline of multi-year sea ice cover have significant ramifications to the entire pan-Arctic region and beyond. Having the recorded average global surface temperature about 0.54°C (0.96°F) above the 20th Century average the decade of 2000-2009 has been the warmest of the 130-year record, with the maximum positive temperatures anomalies in the northern high latitude regions. Satellite records of the Arctic sea ice show a decreasing and accelerating trend in ice extent and concentration since the late 1979, as a result of the global warming. More importantly there is growing evidence that the Arctic sea ice thickness and volume have been decreasing at even faster rate. This means that our knowledge of the Arctic sea ice melt might be significantly biased due to the interpretation of 2-dimensional sea ice extent / concentration records only instead of ice thickness and volume. The rates of recent ice thickness and volume melt derived from our pan-Arctic coupled ice-ocean model results combined with recent remotely sensed data suggest an accelerating negative trend. This trend is robust and lends credence to the postulation that the Arctic not only might but it is likely to be ice-free during the summer in the near future. However, global climate models vary widely in their predictions of warming and the rate of Arctic ice melt, suggesting it may take anywhere from a couple of decades to more than a century to melt most of the summer sea ice cover. Also many regional models are limited in their representation of the rapid Arctic sea ice thinning and volume loss. The inability of models

  16. Ecological genomics for coral and sea urchin conservation in times of climate change

    NASA Astrophysics Data System (ADS)

    Carpizo-Ituarte, E.; Hofmann, G.; Fangue, N.; Cupul-Magaña, A.; Rodríguez-Troncoso, A. P.; Díaz-Pérez, L.; Olivares Bañuelos, T.; Escobar Fernández, R.

    2010-03-01

    If atmospheric CO2 levels continue to increase, it is predicted that the average ocean sea surface temperature will also increase and ocean pH will decrease to levels not experienced by marine organisms for millions of years. Understanding the impact of these stressors will require the study of several marine organisms, and this knowledge will be fundamental to our ability to predict possible effects along large geographical regions and across phyla. Ecological genomics, defined as the use of molecular techniques to answer ecological questions, offers a set of tools that can help us better understand the responses of marine organisms to changes in their environment. In the present work we are using genomic tools to characterize the response of corals and sea urchins to environmental stress. On one side, coral species represent a useful model due to its functions as "environmental sentinels" in tropical ecosystems; on the other hand, species of sea urchins, with the recent sequence of the genome of the purple sea urchin S. purpuratus, offers important genomic resources. Recent results in corals and in sea urchins have shown that the response to stressful conditions can be detected using molecular genomic markers. Continued study of the mRNA expression patterns of several important gene families including calcification genes as well as genes involved in the cellular stress response such as heat shock proteins, will be valuable index of ecological stress in marine systems. These data can be integrated into better strategies of conservation and management of the oceans.

  17. Climate change and Sea level rise: Potential impact on the coast of the Edremit Plain, NW Turkey.

    NASA Astrophysics Data System (ADS)

    Curebal, Isa; Efe, Recep; Soykan, Abdullah; Sonmez, Suleyman

    2015-04-01

    Over the past century, most of the world's mountain glaciers and the ice sheets have lost mass due to global warming. When the temperature exceeds a particular level, glaciers and polar ice caps will continue to lose mass. Recent studies report that low-lying coastal areas will be seriously affected by sea level rise. Changes in the amount of natural and anthropogenic greenhouse gases and aerosols had a warming effect on the global climate during last century. Thus, the pace of melting of ice sheets increased, and, accordingly, sea level began to rise faster. Rise in sea level between 1961 and 2003 was equal to 1.8 mm/year while it was 3.1 mm/year between 1993 and 2003. The total rise in the 20th century is estimated to be between 17 and 19 cm. The models based on the sea level change indicate that the average global temperature at the end of the 21st century will increase by 0.3°C - 6.4°C. Global sea level is projected to rise 8-25 cm by 2030, relative to 2000 levels, 18-48 cm by 2050, and 50-140 cm by 20110. The Edremit Plain lies between Mount Madra and the Kaz Mountains on the coast of Aegean Sea in NW Turkey. It is lowland with an area of 141 km2. The widest part of the plain is 16 km along the E - W direction. The N - S direction amounts to a width of 15 km. The plain is covered with alluvial deposits that settled in the Quaternary Period. The elevation ranges from 0 to 50 m a.s.l. in the plain. This study aims to determine how the low-lying coastal land areas of the Edremit Plain may be affected by possible changes in sea level. Elevation dataset is based on the digital elevation model (DEM) of Landsat ETM + satellite images. To that end, satellite images were used to draw the current coastline. Curves of 2.5, 5, and 10 m were drawn through the use of maps with a scale of 1/25.000. Later on, the areas of the fields between these points were calculated. Current estimates show that 2.5 m rise in sea level will cause sea water to cover an area of 8.6 km2 (%14

  18. Assessment of the impact of sea-level rise due to climate change on coastal groundwater discharge.

    PubMed

    Masciopinto, Costantino; Liso, Isabella Serena

    2016-11-01

    An assessment of sea intrusion into coastal aquifers as a consequence of local sea-level rise (LSLR) due to climate change was carried out at Murgia and Salento in southern Italy. The interpolation of sea-level measurements at three tide-gauge stations was performed during the period of 2000 to 2014. The best fit of measurements shows an increasing rate of LSLR ranging from 4.4mm/y to 8.8mm/y, which will result in a maximum LSLR of approximately 2m during the 22nd century. The local rate of sea-level rise matches recent 21st and 22nd century projections of mean global sea-level rise determined by other researchers, which include increased melting rates of the Greenland and Antarctic ice sheets, the effect of ocean thermal expansion, the melting of glaciers and ice caps, and changes in the quantity of stored land water. Subsequently, Ghyben-Herzberg's equation for the freshwater/saltwater interface was rewritten in order to determine the decrease in groundwater discharge due to the maximum LSLR. Groundwater flow simulations and ArcGIS elaborations of digital elevation models of the coast provided input data for the Ghyben-Herzberg calculation under the assumption of head-controlled systems. The progression of seawater intrusion due to LSLR suggests an impressive depletion of available groundwater discharge during the 22nd century, perhaps as much as 16.1% of current groundwater pumping for potable water in Salento.

  19. Assessment of the impact of sea-level rise due to climate change on coastal groundwater discharge.

    PubMed

    Masciopinto, Costantino; Liso, Isabella Serena

    2016-11-01

    An assessment of sea intrusion into coastal aquifers as a consequence of local sea-level rise (LSLR) due to climate change was carried out at Murgia and Salento in southern Italy. The interpolation of sea-level measurements at three tide-gauge stations was performed during the period of 2000 to 2014. The best fit of measurements shows an increasing rate of LSLR ranging from 4.4mm/y to 8.8mm/y, which will result in a maximum LSLR of approximately 2m during the 22nd century. The local rate of sea-level rise matches recent 21st and 22nd century projections of mean global sea-level rise determined by other researchers, which include increased melting rates of the Greenland and Antarctic ice sheets, the effect of ocean thermal expansion, the melting of glaciers and ice caps, and changes in the quantity of stored land water. Subsequently, Ghyben-Herzberg's equation for the freshwater/saltwater interface was rewritten in order to determine the decrease in groundwater discharge due to the maximum LSLR. Groundwater flow simulations and ArcGIS elaborations of digital elevation models of the coast provided input data for the Ghyben-Herzberg calculation under the assumption of head-controlled systems. The progression of seawater intrusion due to LSLR suggests an impressive depletion of available groundwater discharge during the 22nd century, perhaps as much as 16.1% of current groundwater pumping for potable water in Salento. PMID:27376921

  20. Past occurrences of hypoxia in the Baltic Sea and the role of climate variability, environmental change and human impact

    NASA Astrophysics Data System (ADS)

    Zillén, Lovisa; Conley, Daniel J.; Andrén, Thomas; Andrén, Elinor; Björck, Svante

    2008-12-01

    The hypoxic zone in the Baltic Sea has increased in area about four times since 1960 and widespread oxygen deficiency has severely reduced macro benthic communities below the halocline in the Baltic Proper and the Gulf of Finland, which in turn has affected food chain dynamics, fish habitats and fisheries in the entire Baltic Sea. The cause of increased hypoxia is believed to be enhanced eutrophication through increased anthropogenic input of nutrients, such as nitrogen and phosphorus. However, the spatial variability of hypoxia on long time-scales is poorly known: and so are the driving mechanisms. We review the occurrence of hypoxia in modern time (last c. 50 years), modern historical time (AD 1950-1800) and during the more distant past (the last c. 10 000 years) and explore the role of climate variability, environmental change and human impact. We present a compilation of proxy records of hypoxia (laminated sediments) based on long sediment cores from the Baltic Sea. The cumulated results show that the deeper depressions of the Baltic Sea have experienced intermittent hypoxia during most of the Holocene and that regular laminations started to form c. 8500-7800 cal. yr BP ago, in association with the formation of a permanent halocline at the transition between the Early Littorina Sea and the Littorina Sea s. str. Laminated sediments were deposited during three main periods (i.e. between c. 8000-4000, 2000-800 cal. yr BP and subsequent to AD 1800) which overlap the Holocene Thermal Maximum (c. 9000-5000 cal. yr BP), the Medieval Warm Period (c. AD 750-1200) and the modern historical period (AD 1800 to present) and coincide with intervals of high surface salinity (at least during the Littorina s. str.) and high total organic carbon content. This study implies that there may be a correlation between climate variability in the past and the state of the marine environment, where milder and dryer periods with less freshwater run-off correspond to increased salinities

  1. Climatic change of sea ice mean thickness in the Arctic basin

    SciTech Connect

    Nagurny, A.P.

    1996-12-31

    A method for automatically monitoring sea ice thickness by measuring ice-plate vibration is proposed. Two energy maximums are clearly manifested in the spectrum of ice cover vibrations, corresponding to the resonant waves (the equality of ice eigen frequency as a plate and upper water layer without ice cover) and to the waves at the minimum of the dispersion curve of the ice-water system. The free vibrations of the resonant waves have low amplitudes and can be adequately described by linear theory of elastic gravity wave propagation. Data are presented for sea ice thickness determined by measuring elastic-gravity waves at points in the Arctic basin for the years 1970 through 1992. During this period, a linear decrease in sea ice thickness was observed. The thickness decreased by 12-14 centimeters, or 3 to 4% of average thickenss, overall. Taking into account the significant scattering of data, a trend of climatic warming in the atmosphere-Arctic Ocean system is indicated. 11 refs., 2 figs.

  2. Consequences of climatic change, sea level rise and society evolution on the Kerkennah archipelago coast and sabkha

    NASA Astrophysics Data System (ADS)

    Lucile, Etienne; Gérard, Beltrando; Abdelkarim, Daoud

    2015-04-01

    Interaction between human activities, climate evolution and sea level can be summarised in a system where every element impacts the others. In the Kerkennah archipelago (Tunisia), recent observations have shown that the climate has become more arid, that the sea level is rising and that the society is modernizing at least since 1970. In our work we tried to understand the relations between the elements of the socio-ecosystem of Kerkennah to identify potential causes of the coastline movements and sabkhas extension (low and salty areas). Using photointerpretation (topographic map, Spot 5 image, aerial photographs) and remote sensing (2 landsat TM5 images), we detected and evaluated the movements of the coastline and of the sabkhas limits. Field data have also been added and all information has been used together in a GIS showing a significant retreat of the coastline (maximum of 41.2±6m in 47years) and an increase in the surface of sabkhas (+18%) between 1963 and 2010. The same dataset has been reanalysed at a much finer spatial scale to correlate observed changes to human pressure. This showed that coast erosion rates are more important where the coastline is partially artificialized or just after the end of a dam or a rockfill. Advances to the sea observed on some portions of the coast are always linked to human infrastructures. We conclude that the climatic change and the sea level rise increased the physical vulnerability of the archipelago and that the human installations near the coast amplify this vulnerability. Similarly, the extension of sabkha surfaces is global and most likely due to a natural perturbation of the seasonal cycle in the sabkhas by the sea level rise and by the stronger aridity in summer. However, discrepancies exist between individual areas and can be explained by the presence of active fault and/or by the evolution of agricultural practices. Indeed, frequent periods of drought and the political will for development of the Kerkennah

  3. Potential impacts of climate change on the distribution of longline catches of yellowfin tuna (Thunnus albacares) in the Tasman sea

    NASA Astrophysics Data System (ADS)

    Dell, James T.; Wilcox, Chris; Matear, Richard J.; Chamberlain, Matthew A.; Hobday, Alistair J.

    2015-03-01

    The spatial distribution of living marine resources in the Tasman Sea is expected to shift due to the impacts of global climate change. Understanding the most likely future locations of valuable pelagic species will inform the sustainable harvest and management of species such as yellowfin tuna (YFT; Thunnus albacares). We estimate future upper ocean structure in the Tasman Sea, using both historical data and dynamically downscaled ocean projections for the 2060s, and apply a catch distribution model to estimate possible changes to the YFT catch in the eastern Australia domestic longline fishery. Both approaches project that locations with concentrated YFT catch in the Tasman Sea will shift poleward in response to likely climate change. By the 2060s, the core fishing areas are projected to have shifted both poleward and offshore of existing high catch areas. Shifts in the distribution and hence availability of this species may require future domestic fishing vessels to modify their fishing behaviors, which in turn may require social and economic adjustments.

  4. Climate change impacts on marine water quality: The case study of the Northern Adriatic sea.

    PubMed

    Rizzi, J; Torresan, S; Critto, A; Zabeo, A; Brigolin, D; Carniel, S; Pastres, R; Marcomini, A

    2016-01-30

    Climate change is posing additional pressures on coastal ecosystems due to variations in water biogeochemical and physico-chemical parameters (e.g., pH, salinity) leading to aquatic ecosystem degradation. With the main aim of analyzing the potential impacts of climate change on marine water quality, a Regional Risk Assessment methodology was developed and applied to coastal marine waters of the North Adriatic. It integrates the outputs of regional biogeochemical and physico-chemical models considering future climate change scenarios (i.e., years 2070 and 2100) with site-specific environmental and socio-economic indicators. Results showed that salinity and temperature will be the main drivers of changes, together with macronutrients, especially in the area of the Po' river delta. The final outputs are exposure, susceptibility and risk maps supporting the communication of the potential consequences of climate change on water quality to decision makers and stakeholders and provide a basis for the definition of adaptation and management strategies. PMID:26152856

  5. Analysis of Sea Level Rise and Variability: On the Connections Between Observed Coastal Sea Level and Climatic Changes in Ocean Circulation

    NASA Astrophysics Data System (ADS)

    Ezer, T.

    2012-12-01

    Relative sea level rise (SLR) rates obtained from coastal tide gauge data show considerable spatial variations. These variations are partly related to land subsidence/uplifting, but additional contributions due to changes in ocean dynamics are not well understood. For example, sea level in the Chesapeake Bay and the Mid-Atlantic region has been rising 2-3 times faster than the global SLR, and until recently this has been attributed mostly to land subsidence. However, recent studies suggest that a significant contribution to local SLR along the US east coast between Cape Hatteras and Cape Code may be due to climate-related weakening of the Atlantic Meridional Overturning Circulation. Some model studies in fact found correlations between variations in the strength of the Gulf Stream and coastal sea level. A new analysis of sea level data is introduced. The method is based on Empirical Mode Decomposition (EMD) and Hilbert-Huang Transformation (HHT), which separates the SLR trend from other oscillating modes and shows how the SLR changes with time. Bootstrap calculations were used to test the robustness of the method and obtain confidence levels. The analysis tries to overcome problems associated with sea level records that are not long enough to obtain accurate SLR acceleration or deceleration and separate trends from decadal and multi-decadal global and basin-scale oscillations. The results show for example, an accelerated SLR in the Chesapeake Bay that is larger than global estimates, but comparable to recent findings that propose that such acceleration may be due to changes in ocean dynamics. The various modes of sea level variability found by the analysis are compared with other data, such as the Gulf Stream transport and its location, in order to investigate the time-scales and mechanisms which connect variations in local sea level with large-scale ocean circulation.

  6. Ecological niche modeling of coastal dune plants and future potential distribution in response to climate change and sea level rise.

    PubMed

    Mendoza-González, Gabriela; Martínez, M Luisa; Rojas-Soto, Octavio R; Vázquez, Gabriela; Gallego-Fernández, Juan B

    2013-08-01

    Climate change (CC) and sea level rise (SLR) are phenomena that could have severe impacts on the distribution of coastal dune vegetation. To explore this we modeled the climatic niches of six coastal dunes plant species that grow along the shoreline of the Gulf of Mexico and the Yucatan Peninsula, and projected climatic niches to future potential distributions based on two CC scenarios and SLR projections. Our analyses suggest that distribution of coastal plants will be severely limited, and more so in the case of local endemics (Chamaecrista chamaecristoides, Palafoxia lindenii, Cakile edentula). The possibilities of inland migration to the potential 'new shoreline' will be limited by human infrastructure and ecosystem alteration that will lead to a 'coastal squeeze' of the coastal habitats. Finally, we identified areas as future potential refuges for the six species in central Gulf of Mexico, and northern Yucatán Peninsula especially under CC and SLR scenarios. PMID:23625760

  7. Ecological niche modeling of coastal dune plants and future potential distribution in response to climate change and sea level rise.

    PubMed

    Mendoza-González, Gabriela; Martínez, M Luisa; Rojas-Soto, Octavio R; Vázquez, Gabriela; Gallego-Fernández, Juan B

    2013-08-01

    Climate change (CC) and sea level rise (SLR) are phenomena that could have severe impacts on the distribution of coastal dune vegetation. To explore this we modeled the climatic niches of six coastal dunes plant species that grow along the shoreline of the Gulf of Mexico and the Yucatan Peninsula, and projected climatic niches to future potential distributions based on two CC scenarios and SLR projections. Our analyses suggest that distribution of coastal plants will be severely limited, and more so in the case of local endemics (Chamaecrista chamaecristoides, Palafoxia lindenii, Cakile edentula). The possibilities of inland migration to the potential 'new shoreline' will be limited by human infrastructure and ecosystem alteration that will lead to a 'coastal squeeze' of the coastal habitats. Finally, we identified areas as future potential refuges for the six species in central Gulf of Mexico, and northern Yucatán Peninsula especially under CC and SLR scenarios.

  8. Consequences of twenty-first-century policy for multi-millennial climate and sea-level change

    NASA Astrophysics Data System (ADS)

    Clark, Peter U.; Shakun, Jeremy D.; Marcott, Shaun A.; Mix, Alan C.; Eby, Michael; Kulp, Scott; Levermann, Anders; Milne, Glenn A.; Pfister, Patrik L.; Santer, Benjamin D.; Schrag, Daniel P.; Solomon, Susan; Stocker, Thomas F.; Strauss, Benjamin H.; Weaver, Andrew J.; Winkelmann, Ricarda; Archer, David; Bard, Edouard; Goldner, Aaron; Lambeck, Kurt; Pierrehumbert, Raymond T.; Plattner, Gian-Kasper

    2016-04-01

    Most of the policy debate surrounding the actions needed to mitigate and adapt to anthropogenic climate change has been framed by observations of the past 150 years as well as climate and sea-level projections for the twenty-first century. The focus on this 250-year window, however, obscures some of the most profound problems associated with climate change. Here, we argue that the twentieth and twenty-first centuries, a period during which the overwhelming majority of human-caused carbon emissions are likely to occur, need to be placed into a long-term context that includes the past 20 millennia, when the last Ice Age ended and human civilization developed, and the next ten millennia, over which time the projected impacts of anthropogenic climate change will grow and persist. This long-term perspective illustrates that policy decisions made in the next few years to decades will have profound impacts on global climate, ecosystems and human societies -- not just for this century, but for the next ten millennia and beyond.

  9. Pliocene-Pleistocene climate change, sea level and uplift history recorded by the Horingbaai fan-delta, NW Namibia

    NASA Astrophysics Data System (ADS)

    Stollhofen, Harald; Stanistreet, Ian G.; von Hagke, Christoph; Nguno, Anna

    2014-07-01

    Its location on a tectonically relatively stable passive margin and its degree of interaction with the sea make the Horingbaai fan-delta, NW Namibia, an exceptional record of coastal activity, providing insights into the response of ephemeral fluvial systems to changes in climate, sea level and continent-scale uplift. The fan comprises upper, middle and lower segments. The upper fan and middle fan are dominated by a braided river system; only in the upper fan are fluvial sediments interleaved with hyperconcentrated flow deposits. Plio-Pleistocene sea level highstands have left marine terraces on the fan surface which enable correlation with the offshore marine record and provide timelines to constrain fan growth. The bulk of fan-delta progradation took place at ∼ 2.7-2.4 Ma, between the formation of a widespread erosional surface incising the middle Pliocene Karpfenkliff and Kamberg Formations, but prior to the emplacement of the warm-water fauna-bearing late Pliocene "Oyster Terrace" (∼ 2.4-2.2 Ma), an equivalent of the + 30 mP (marine terrace package) in coastal southwestern Africa. Major fan progradation is contemporaneous with widespread regional uplift (~ 12 ± 5 m/Ma) and climate change in southwestern Africa, the latter associated with intensification of northern hemisphere glaciations. Younger fan growth phases are weaker and constrained by < 10 m asl marine terrace bodies that yield mostly cold-water fauna, corresponding to the onset of strong glacial/interglacial climatic fluctuations superimposed on a general aridification trend and the introduction of colder sea-surface temperatures after 2.2 Ma.

  10. Marine response to climate changes during the last five millennia in the central Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Margaritelli, G.; Vallefuoco, M.; Di Rita, F.; Capotondi, L.; Bellucci, L. G.; Insinga, D. D.; Petrosino, P.; Bonomo, S.; Cacho, I.; Cascella, A.; Ferraro, L.; Florindo, F.; Lubritto, C.; Lurcock, P. C.; Magri, D.; Pelosi, N.; Rettori, R.; Lirer, F.

    2016-07-01

    We present a high-resolution paleoclimatic and paleoenvironmental reconstruction of the last five millennia from a shallow water marine sedimentary record from the central Tyrrhenian Sea (Gulf of Gaeta) using planktonic foraminifera, pollen, oxygen stable isotope, tephrostratigrapy and magnetostratigrapy. This multiproxy approach allows to evidence and characterize nine time intervals associated with archaeological/cultural periods: Eneolithic (base of the core-ca. 2410 BCE), Early Bronze Age (ca. 2410 BCE-ca. 1900 BCE), Middle Bronze Age-Iron Age (ca. 1900 BCE-ca. 500 BCE), Roman Period (ca. 500 BCE-ca. 550 CE), Dark Age (ca. 550 CE-ca. 860 CE), Medieval Climate Anomaly (ca. 860 CE-ca. 1250 CE), Little Ice Age (ca. 1250 CE-ca. 1850 CE), Industrial Period (ca. 1850 CE-ca. 1950 CE), Modern Warm Period (ca. 1950 CE-present day). The reconstructed climatic evolution in the investigated sedimentary succession is coherent with the short-term climate variability documented at the Mediterranean scale. By integrating the planktonic foraminiferal turnover from carnivorous to herbivorous-opportunistic species, the oxygen isotope record and the pollen distribution, we document important modification from the onset of the Roman Period to the present-day. From ca. 500 CE upwards the documentation of the cooling trend punctuated by climate variability at secular scale evidenced by the short-term δ18O is very detailed. We hypothesise that the present day warm conditions started from the end of cold Maunder event. Additionally, we provide that the North Atlantic Oscillation (NAO) directly affected the central Mediterranean region during the investigated time interval.

  11. Temperature, but not pH, compromises sea urchin fertilization and early development under near-future climate change scenarios.

    PubMed

    Byrne, Maria; Ho, Melanie; Selvakumaraswamy, Paulina; Nguyen, Hong D; Dworjanyn, Symon A; Davis, Andy R

    2009-05-22

    Global warming is causing ocean warming and acidification. The distribution of Heliocidaris erythrogramma coincides with the eastern Australia climate change hot spot, where disproportionate warming makes marine biota particularly vulnerable to climate change. In keeping with near-future climate change scenarios, we determined the interactive effects of warming and acidification on fertilization and development of this echinoid. Experimental treatments (20-26 degrees C, pH 7.6-8.2) were tested in all combinations for the 'business-as-usual' scenario, with 20 degrees C/pH 8.2 being ambient. Percentage of fertilization was high (>89%) across all treatments. There was no difference in percentage of normal development in any pH treatment. In elevated temperature conditions, +4 degrees C reduced cleavage by 40 per cent and +6 degrees C by a further 20 per cent. Normal gastrulation fell below 4 per cent at +6 degrees C. At 26 degrees C, development was impaired. As the first study of interactive effects of temperature and pH on sea urchin development, we confirm the thermotolerance and pH resilience of fertilization and embryogenesis within predicted climate change scenarios, with negative effects at upper limits of ocean warming. Our findings place single stressor studies in context and emphasize the need for experiments that address ocean warming and acidification concurrently. Although ocean acidification research has focused on impaired calcification, embryos may not reach the skeletogenic stage in a warm ocean.

  12. Temperature, but not pH, compromises sea urchin fertilization and early development under near-future climate change scenarios.

    PubMed

    Byrne, Maria; Ho, Melanie; Selvakumaraswamy, Paulina; Nguyen, Hong D; Dworjanyn, Symon A; Davis, Andy R

    2009-05-22

    Global warming is causing ocean warming and acidification. The distribution of Heliocidaris erythrogramma coincides with the eastern Australia climate change hot spot, where disproportionate warming makes marine biota particularly vulnerable to climate change. In keeping with near-future climate change scenarios, we determined the interactive effects of warming and acidification on fertilization and development of this echinoid. Experimental treatments (20-26 degrees C, pH 7.6-8.2) were tested in all combinations for the 'business-as-usual' scenario, with 20 degrees C/pH 8.2 being ambient. Percentage of fertilization was high (>89%) across all treatments. There was no difference in percentage of normal development in any pH treatment. In elevated temperature conditions, +4 degrees C reduced cleavage by 40 per cent and +6 degrees C by a further 20 per cent. Normal gastrulation fell below 4 per cent at +6 degrees C. At 26 degrees C, development was impaired. As the first study of interactive effects of temperature and pH on sea urchin development, we confirm the thermotolerance and pH resilience of fertilization and embryogenesis within predicted climate change scenarios, with negative effects at upper limits of ocean warming. Our findings place single stressor studies in context and emphasize the need for experiments that address ocean warming and acidification concurrently. Although ocean acidification research has focused on impaired calcification, embryos may not reach the skeletogenic stage in a warm ocean. PMID:19324767

  13. Climate change overruns resilience conferred by temperature-dependent sex determination in sea turtles and threatens their survival.

    PubMed

    Santidrián Tomillo, Pilar; Genovart, Meritxell; Paladino, Frank V; Spotila, James R; Oro, Daniel

    2015-08-01

    Temperature-dependent sex determination (TSD) is the predominant form of environmental sex determination (ESD) in reptiles, but the adaptive significance of TSD in this group remains unclear. Additionally, the viability of species with TSD may be compromised as climate gets warmer. We simulated population responses in a turtle with TSD to increasing nest temperatures and compared the results to those of a virtual population with genotypic sex determination (GSD) and fixed sex ratios. Then, we assessed the effectiveness of TSD as a mechanism to maintain populations under climate change scenarios. TSD populations were more resilient to increased nest temperatures and mitigated the negative effects of high temperatures by increasing production of female offspring and therefore, future fecundity. That buffered the negative effect of temperature on the population growth. TSD provides an evolutionary advantage to sea turtles. However, this mechanism was only effective over a range of temperatures and will become inefficient as temperatures rise to levels projected by current climate change models. Projected global warming threatens survival of sea turtles, and the IPCC high gas concentration scenario may result in extirpation of the studied population in 50 years.

  14. Climate change overruns resilience conferred by temperature-dependent sex determination in sea turtles and threatens their survival.

    PubMed

    Santidrián Tomillo, Pilar; Genovart, Meritxell; Paladino, Frank V; Spotila, James R; Oro, Daniel

    2015-08-01

    Temperature-dependent sex determination (TSD) is the predominant form of environmental sex determination (ESD) in reptiles, but the adaptive significance of TSD in this group remains unclear. Additionally, the viability of species with TSD may be compromised as climate gets warmer. We simulated population responses in a turtle with TSD to increasing nest temperatures and compared the results to those of a virtual population with genotypic sex determination (GSD) and fixed sex ratios. Then, we assessed the effectiveness of TSD as a mechanism to maintain populations under climate change scenarios. TSD populations were more resilient to increased nest temperatures and mitigated the negative effects of high temperatures by increasing production of female offspring and therefore, future fecundity. That buffered the negative effect of temperature on the population growth. TSD provides an evolutionary advantage to sea turtles. However, this mechanism was only effective over a range of temperatures and will become inefficient as temperatures rise to levels projected by current climate change models. Projected global warming threatens survival of sea turtles, and the IPCC high gas concentration scenario may result in extirpation of the studied population in 50 years. PMID:25929883

  15. Analyzing the Effects of Climate Change on Sea Surface Temperature in Monitoring Coral Reef Health in the Florida Keys Using Sea Surface Temperature Data

    NASA Technical Reports Server (NTRS)

    Jones, Jason; Burbank, Renane; Billiot, Amanda; Schultz, Logan

    2011-01-01

    This presentation discusses use of 4 kilometer satellite-based sea surface temperature (SST) data to monitor and assess coral reef areas of the Florida Keys. There are growing concerns about the impacts of climate change on coral reef systems throughout the world. Satellite remote sensing technology is being used for monitoring coral reef areas with the goal of understanding the climatic and oceanic changes that can lead to coral bleaching events. Elevated SST is a well-documented cause of coral bleaching events. Some coral monitoring studies have used 50 km data from the Advanced Very High Resolution Radiometer (AVHRR) to study the relationships of sea surface temperature anomalies to bleaching events. In partnership with NOAA's Office of National Marine Sanctuaries and the University of South Florida's Institute for Marine Remote Sensing, this project utilized higher resolution SST data from the Terra's Moderate Resolution Imaging Spectroradiometer (MODIS) and AVHRR. SST data for 2000-2010 was employed to compute sea surface temperature anomalies within the study area. The 4 km SST anomaly products enabled visualization of SST levels for known coral bleaching events from 2000-2010.

  16. Climate change and inuits

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The Inuit Circumpolar Conference will seek a declaration from the Inter-American Commission on Human Rights that emissions of greenhouse gases, which the conference says, are destroying the Inuit way of life, are a violation of human rights, conference chair Sheila Watt-Cloutier announced on 15 December.Her announcement comes shortly after the mid-November release of the Arctic Climate Impact Assessment, a scientific study by an international team of 300 scientists. That assessment noted, “The Arctic is now experiencing some of the most rapid and severe climate change on Earth. Over the next 100 years, climate change is expected to accelerate, contributing to major physical, ecological, social, and economic changes, many of which have already begun. Changes in Arctic climate will also affect the rest of the world through increased global warming and rising sea levels.”

  17. Impact of relative sea level and rapid climate changes on the architecture and lithofacies of the Holocene Rhone subaqueous delta (Western Mediterranean Sea)

    NASA Astrophysics Data System (ADS)

    Fanget, Anne-Sophie; Berné, Serge; Jouet, Gwénaël; Bassetti, Maria-Angela; Dennielou, Bernard; Maillet, Grégoire M.; Tondut, Mathieu

    2014-05-01

    results from condensation/erosion, which appears as an important process even within supply-dominated deltaic systems, due to avulsion of distributaries. The age of the MFS varies along-strike between ca. 7.8 and 5.6 kyr cal. BP in relation to the position of depocentres and climatically-controlled sediment supply. The last rapid climate change of the Holocene, the Little Ice Age (1250-1850 AD), had a distinct stratigraphic influence on the architecture and lithofacies of the Rhone subaqueous delta through the progradation of two deltaic lobes. In response to changes in sediment supply linked to rapid climate changes (and to anthropic factors), the Rhone delta evolved from wave-dominated to fluvial dominated, and then wave dominated again.

  18. Stratigraphic signature of sub-orbital climate and sea-level changes in the Gulf of Lions (NW Mediterranean Sea)

    NASA Astrophysics Data System (ADS)

    Berne, S. P.; Bassetti, M. A.; Baumann, J.; Dennielou, B.; Jouet, G.; Mauffrey, M.; Sierro, F. J.

    2014-12-01

    The Promess boreholes in the Gulf of Lions (NW Mediterranean) provide precise chrono-stratigraphic constraints of the last ca 500 ky, that were nicely preserved at the shelf edge due to high accommodation and important sediment supply from the Rhone River. The major stratigraphic elements in this physiographic domain are Falling Stage Systems Tracts (in the sense of SEPM) linked to 100-ky eustatic cycles. They form wedges pinching out on the middle shelf, and thickening seaward on the outer shelf/upper slope (about 30-40m thick on the outer shelf). Within the uppermost sequence, linked to the last Glacial-Interglacial cycle, internal discontinuities were long described, but they were assigned to autogenic processes such as lobe avulsion or bedform migration. However, careful interpretation of a dense grid of very high resolution seismic data, together with precise chronostratigraphic constraints from borehole data and long piston cores, reveal that distinct parasequences, correlable at the regional scale, correspond to relatively minor sea-level changes linked (a) to Bond Cycles during the end of the Last Glacial, and (b) to an early Melt Water Pulse at the onset of Deglacial sea-level rise. These regressive and transgressive (respectively) parasequences are particularly well preserved in canyon heads, due to better accommodation. We propose that such features are important building blocks of the stratigraphic record, that might be recognized elsewhere on modern continental margins, as well as in the rock record.

  19. The impacts of climate change and environmental management policies on the trophic regimes in the Mediterranean Sea: Scenario analyses

    NASA Astrophysics Data System (ADS)

    Lazzari, P.; Mattia, G.; Solidoro, C.; Salon, S.; Crise, A.; Zavatarelli, M.; Oddo, P.; Vichi, M.

    2014-07-01

    The impacts of climate change and environmental management policies on the Mediterranean Sea were analyzed in multi-annual simulations of carbon cycling in a planktonic ecosystem model. The modeling system is based on a high-resolution coupled physical-biogeochemical ocean model that is off-line and forced by medium-resolution global climate simulations and by estimates of continental and river inputs of freshwater and nutrients. The simulations span the periods 1990-2000 and 2090-2100, assuming the IPCC SRES A1B scenario of climatic change at the end of the century. The effects of three different options on land use, mediated through rivers, are also considered. All scenarios indicate that the increase in temperature fuels an increase in metabolic rates. The gross primary production increases approximately 5% over the present-day figures, but the changes in productivity rates are compensated by augmented community respiration rates, so the net community production is stable with respect to present-day figures. The 21st century simulations are characterized by a reduction in the system biomass and by an enhanced accumulation of semi-labile dissolved organic matter. The largest changes in organic carbon production occur close to rivers, where the influence of changes in future nutrient is higher.

  20. Sediment dynamics in the Mekong Delta: impacts of planned hydropower development, climate change and sea level rise

    NASA Astrophysics Data System (ADS)

    Van Manh, Nguyen; Viet Dung, Nguyen; Nghia Hung, Nguyen; Kummu, Matti; Merz, Bruno; Apel, Heiko

    2016-04-01

    The Mekong Delta is under threat due to human activities endangering the livelihood of millions of people. Hydropower development, climate change and the combined effects of sea level rise and deltaic subsidence are the main drivers impacting future flow regimes, sedimentation patterns and erosion in the Mekong Delta. In order to estimate the individual and combined impacts of the different drivers sensitivity-based scenario simulations were performed. The hydraulic processes and the sediment transport and deposition in the Mekong delta including the Tonle Sap Lake was simulated with a quasi-2D hydrodynamic for a baseline (2000-2010) and a future (2050-2060) period. For each driver a plausible range of future states was determined based on existing literature and studies. The ranges were discretized into different levels, resulting in 216 combinations of driver combinations. The results thus cover all plausible future pathways of sediment dynamics in the delta based on current knowledge. The results indicate that hydropower development dominates the changes in floodplain sediment dynamics of the Mekong Delta, while sea level rise has the smallest effect. The floodplains of the Vietnamese Mekong Delta are much more sensitive to the changes compared to other subsystems of the delta. The median changes of the three drivers combined indicate that the inundation extent would increase slightly, but the overall floodplain sedimentation would decrease by approximately 40%, and the suspended sediment load to the South China Sea would diminish to half of the current rates. The maximum changes in all drivers would mean a nearly 90% reduction of delta sedimentation, and a 95% reduction of the suspended sediment reaching the sea. These findings provide new and valuable information on the possible future development of floodplain hydraulics and sedimentation in the Mekong Delta, and identify the areas that are most vulnerable to these changes. This, in turn, provides a

  1. Future sediment dynamics in the Mekong Delta floodplains: Impacts of hydropower development, climate change and sea level rise

    NASA Astrophysics Data System (ADS)

    Manh, Nguyen Van; Dung, Nguyen Viet; Hung, Nguyen Nghia; Kummu, Matti; Merz, Bruno; Apel, Heiko

    2015-04-01

    The Mekong Delta is under threat due to human activities that are endangering livelihood of millions of people. Hydropower development, climate change and the combined effects of sea level rise and deltaic subsidence are the main drivers impacting future flow regimes and sedimentation patterns in the Mekong Delta. We develop a sensitivity-based approach to assess the response of the floodplain hydrology and sediment dynamics in the delta to these drivers. A quasi-2D hydrodynamic model of suspended sediment dynamics is used to simulate the sediment transport and sediment deposition in the delta, including Tonle Sap Lake, for a baseline (2000-2010) and a future (2050-2060) period. For each driver we derive a plausible range of future states and discretize it into different levels, resulting in 216 combinations. Our results thus cover all plausible future pathways of sediment dynamics in the delta based on current knowledge. Our results indicate that hydropower development dominates the changes in floodplain sediment dynamics of the Mekong Delta, while sea level rise has the smallest effect. The floodplains of the Vietnamese Mekong Delta are much more sensitive to the changes compared to the other subsystems of the delta. The median changes of the three drivers combined indicate that the inundation extent would increase slightly, but the overall floodplain sedimentation would decrease by approximately 40%, and the sediment load to the South China Sea would diminish to half of the current rates. The maximum changes in all drivers would mean a nearly 90% reduction of delta sedimentation and a 95% reduction of the sediment reaching the sea. Our findings provide new and valuable information on the possible future development of floodplain hydraulics and sedimentation in the Mekong Delta and identify the areas that are most vulnerable to these changes.

  2. Mind the gap in SEA: An institutional perspective on why assessment of synergies amongst climate change mitigation, adaptation and other policy areas are missing

    SciTech Connect

    Vammen Larsen, Sanne; Kornov, Lone; Wejs, Anja

    2012-02-15

    This article takes its point of departure in two approaches to integrating climate change into Strategic Environmental Assessment (SEA): Mitigation and adaptation, and in the fact that these, as well as the synergies between them and other policy areas, are needed as part of an integrated assessment and policy response. First, the article makes a review of how positive and negative synergies between a) climate change mitigation and adaptation and b) climate change and other environmental concerns are integrated into Danish SEA practice. Then, the article discusses the implications of not addressing synergies. Finally, the article explores institutional explanations as to why synergies are not addressed in SEA practice. A document analysis of 149 Danish SEA reports shows that only one report comprises the assessment of synergies between mitigation and adaptation, whilst 9,4% of the reports assess the synergies between climate change and other environmental concerns. The consequences of separation are both the risk of trade-offs and missed opportunities for enhancing positive synergies. In order to propose explanations for the lacking integration, the institutional background is analysed and discussed, mainly based on Scott's theory of institutions. The institutional analysis highlights a regulatory element, since the assessment of climate change synergies is underpinned by legislation, but not by guidance. This means that great focus is on normative elements such as the local interpretation of legislation and of climate change mitigation and adaptation. The analysis also focuses on how the fragmentation of the organisation in which climate change and SEA are embedded has bearings on both normative and cultural-cognitive elements. This makes the assessment of synergies challenging. The evidence gathered and presented in the article points to a need for developing the SEA process and methodology in Denmark with the aim to include climate change in the assessments in a

  3. Relative impact of sea level rise, wave climate and anthropogenic actions on the recent shoreline changes of the Pacific Islands

    NASA Astrophysics Data System (ADS)

    Garcin, M.; Baills, A.; Yates, M.; Le Cozannet, G.; Bulteau, T.; Salai, E.; Sauter, J.

    2012-04-01

    Sea level rise is nowadays one of a major concern for many low-lying and highly populated areas in the world. However, it is difficult to forecast the consequences of sea levels rise in terms of erosion, due to the interactions with many forcing factors of the evolution of coastline mobility. Indeed, climatic factors such as sea level rise are combined with internal and external geodynamic processes, biological factors, wave forcing and anthropogenic actions which can also play an important role in coastline mobility. Understanding the whole system and its past evolutions is necessary to anticipate future changes. Within the on-going CECILE project, our goal is to evaluate the impact of future sea level change on some emblematic coasts located in different part of the world in order to assess their sensitivity and the variability of their response to different change rise rates. This work presents the study conducted on coastlines of two regions of the Pacific: French Polynesia (SW Pacific) and New Caledonia. In order to evaluate the sensitivity of the coastlines to sea level rise, we firstly analysed the response of each coastline during the sea level rise of the past 50 years, using a diachronic analysis of ancient and recent remote sensing images. Then we also took into account the evolution of anthropogenic actions contributing to modifications of the sedimentary budget at the coast, and finally, sea level variations, using the sea level reconstruction of Becker et al. (2012) of the 2nd half of the XXth century. Two atolls of French Polynesia (Manihi and Scilly) and six coastal stretches of New Caledonia have been studied. Although Manihi and Scilly experienced a sea level rise rate twice as important as the global mean according to Becker et al. (2012), wave forcing was, during the last 50 years, the dominant factor controlling the shoreline evolution and aggradation/erosion processes on the atolls. On the contrary, on the main island of New Caledonia, the

  4. Relationship between historical sea-surface temperature variability and climate change-induced coral mortality in the western Indian Ocean.

    PubMed

    Ateweberhan, M; McClanahan, Tim R

    2010-07-01

    Many of the world's coral reefs suffered high coral mortality during the 1998 ENSO, with the highest mortality in the western Indian Ocean (WIO). A meta-analysis of field data on change in coral cover across the 1998 ENSO event was conducted for 36 major reef areas in the WIO, and relationship of the change with the historical sea-surface temperature (SST) variability investigated. WIO reefs were categorized into three major SST groups of differing coral cover change. Cover change was negatively associated with standard deviation (SD) SST until about SD 2.3, with increasing flatness of the SST frequency distributions. It increased with further increase in SD as the SST distributions became strongly bimodal in the Arabian/Persian Gulf area. The study indicates that environmental resistance/tolerance to extreme anomalous events could be predicted and management priorities directed accordingly for a warmer and more variable future climate.

  5. Dramatic declines in Euphausia pacifica abundance in the East China Sea: response to recent regional climate change.

    PubMed

    Xu, Zhao-Li; Zhang, Dong

    2014-03-01

    As with other marine ecosystems around the world, water temperature has been anomalously warm in recent years in the East China Sea. We analyzed historical data to explore the effects of climatic change on the abundance and distribution variation of Euphausia pacifica in the East China Sea (the Changjiang River estuary and adjacent areas). In 1959, the highest abundance occurred in the spring and autumn, and this krill species was still abundant in May 1974; however, its abundance was significantly reduced in 2002, markedly in spring. Euphausia pacifica was the numerically dominant euphausiid in the East China Sea in 1959. Its mean abundance was up to 1.91 ind m(-3) and 1.64 ind/m(3) in 1959 and 1974, respectively; however, this figure decreased to 0.36 ind m(-3) in 2002. Since 2003, the abundances have been near zero in the most years. Both inter-annual (between November 1959 and 2002) and inter-monthly (between May and June 1959) comparisons suggest that E. pacifica has had a temperature-driven northward movement in response to rising sea surface temperature, especially the positive anomalies since 1997. However, E. pacifica did not come back to the previous habitat when temperature became relative cold. Hence additional factors affecting the E. pacifica distribution and abundance need to be investigated in the future study.

  6. Flooded! An Investigation of Sea-Level Rise in a Changing Climate

    ERIC Educational Resources Information Center

    Gillette, Brandon; Hamilton, Cheri

    2011-01-01

    Explore how melting ice sheets affect global sea levels. Sea-level rise (SLR) is a rise in the water level of the Earth's oceans. There are two major kinds of ice in the polar regions: sea ice and land ice. Land ice contributes to SLR and sea ice does not. This article explores the characteristics of sea ice and land ice and provides some hands-on…

  7. Climate-physics-chemistry-biology: connected changes in the Black Sea regimes.

    NASA Astrophysics Data System (ADS)

    Pakhomova, Svetlana; Silkin, Vladimir; Podymov, Oleg; Chasovnikov, Valery

    2016-04-01

    /P ratio, <16, coccolithophores are a dominant species, at N/P>16 diatoms dominate in the system. The years 2006 and 2012, years with coldest winters and intensive vertical mixing, were characterized by a very high concentration of phosphorus and a low N/P ratio during most of the year, especially in 2012. This followed by massive boom of coccolithophores during these years. Years 2007 and 2008 showed an opposite situation - a low phosphorus concentration, high N/P ratio and diatoms as dominant species only. Thereby during the last decade in the NE Black Sea the main forcing is climate that determines the hydrophysical regime, vertical mixing, that affected the hydrochemical regime, the supply of nutrients to the surface layer, that controls the hydrobiological regime, the structure of phytoplankton community.

  8. Impacts of past climate and sea level change on Everglades wetlands: placing a century of anthropogenic change into a late-Holocene context

    USGS Publications Warehouse

    Willard, D.A.; Bernhardt, C.E.

    2011-01-01

    We synthesize existing evidence on the ecological history of the Florida Everglades since its inception ~7 ka (calibrated kiloannum) and evaluate the relative impacts of sea level rise, climate variability, and human alteration of Everglades hydrology on wetland plant communities. Initial freshwater peat accumulation began between 6 and 7 ka on the platform underlying modern Florida Bay when sea level was ~6.2 m below its current position. By 5 ka, sawgrass and waterlily peats covered the area bounded by Lake Okeechobee to the north and the Florida Keys to the south. Slower rates of relative sea level rise ~3 ka stabilized the south Florida coastline and initiated transitions from freshwater to mangrove peats near the coast. Hydrologic changes in freshwater marshes also are indicated ~3 ka. During the last ~2 ka, the Everglades wetland was affected by a series of hydrologic fluctuations related to regional to global-scale fluctuations in climate and sea level. Pollen evidence indicates that regional-scale droughts lasting two to four centuries occurred ~1 ka and ~0.4 ka, altering wetland community composition and triggering development of characteristic Everglades habitats such as sawgrass ridges and tree islands. Intercalation of mangrove peats with estuarine muds ~1 ka indicates a temporary slowing or stillstand of sea level. Although sustained droughts and Holocene sea level rise played large roles in structuring the greater Everglades ecosystem, twentieth century reductions in freshwater flow, compartmentalization of the wetland, and accelerated rates of sea level rise had unprecedented impacts on oxidation and subsidence of organic soils, changes/loss of key Everglades habitats, and altered distribution of coastal vegetation.

  9. A vulnerability assessment of 300 species in Florida: threats from sea level rise, land use, and climate change.

    PubMed

    Reece, Joshua Steven; Noss, Reed F; Oetting, Jon; Hoctor, Tom; Volk, Michael

    2013-01-01

    Species face many threats, including accelerated climate change, sea level rise, and conversion and degradation of habitat from human land uses. Vulnerability assessments and prioritization protocols have been proposed to assess these threats, often in combination with information such as species rarity; ecological, evolutionary or economic value; and likelihood of success. Nevertheless, few vulnerability assessments or prioritization protocols simultaneously account for multiple threats or conservation values. We applied a novel vulnerability assessment tool, the Standardized Index of Vulnerability and Value, to assess the conservation priority of 300 species of plants and animals in Florida given projections of climate change, human land-use patterns, and sea level rise by the year 2100. We account for multiple sources of uncertainty and prioritize species under five different systems of value, ranging from a primary emphasis on vulnerability to threats to an emphasis on metrics of conservation value such as phylogenetic distinctiveness. Our results reveal remarkable consistency in the prioritization of species across different conservation value systems. Species of high priority include the Miami blue butterfly (Cyclargus thomasi bethunebakeri), Key tree cactus (Pilosocereus robinii), Florida duskywing butterfly (Ephyriades brunnea floridensis), and Key deer (Odocoileus virginianus clavium). We also identify sources of uncertainty and the types of life history information consistently missing across taxonomic groups. This study characterizes the vulnerabilities to major threats of a broad swath of Florida's biodiversity and provides a system for prioritizing conservation efforts that is quantitative, flexible, and free from hidden value judgments. PMID:24260447

  10. A Vulnerability Assessment of 300 Species in Florida: Threats from Sea Level Rise, Land Use, and Climate Change

    PubMed Central

    Reece, Joshua Steven; Noss, Reed F.; Oetting, Jon; Hoctor, Tom; Volk, Michael

    2013-01-01

    Species face many threats, including accelerated climate change, sea level rise, and conversion and degradation of habitat from human land uses. Vulnerability assessments and prioritization protocols have been proposed to assess these threats, often in combination with information such as species rarity; ecological, evolutionary or economic value; and likelihood of success. Nevertheless, few vulnerability assessments or prioritization protocols simultaneously account for multiple threats or conservation values. We applied a novel vulnerability assessment tool, the Standardized Index of Vulnerability and Value, to assess the conservation priority of 300 species of plants and animals in Florida given projections of climate change, human land-use patterns, and sea level rise by the year 2100. We account for multiple sources of uncertainty and prioritize species under five different systems of value, ranging from a primary emphasis on vulnerability to threats to an emphasis on metrics of conservation value such as phylogenetic distinctiveness. Our results reveal remarkable consistency in the prioritization of species across different conservation value systems. Species of high priority include the Miami blue butterfly (Cyclargus thomasi bethunebakeri), Key tree cactus (Pilosocereus robinii), Florida duskywing butterfly (Ephyriades brunnea floridensis), and Key deer (Odocoileus virginianus clavium). We also identify sources of uncertainty and the types of life history information consistently missing across taxonomic groups. This study characterizes the vulnerabilities to major threats of a broad swath of Florida’s biodiversity and provides a system for prioritizing conservation efforts that is quantitative, flexible, and free from hidden value judgments. PMID:24260447

  11. A vulnerability assessment of 300 species in Florida: threats from sea level rise, land use, and climate change.

    PubMed

    Reece, Joshua Steven; Noss, Reed F; Oetting, Jon; Hoctor, Tom; Volk, Michael

    2013-01-01

    Species face many threats, including accelerated climate change, sea level rise, and conversion and degradation of habitat from human land uses. Vulnerability assessments and prioritization protocols have been proposed to assess these threats, often in combination with information such as species rarity; ecological, evolutionary or economic value; and likelihood of success. Nevertheless, few vulnerability assessments or prioritization protocols simultaneously account for multiple threats or conservation values. We applied a novel vulnerability assessment tool, the Standardized Index of Vulnerability and Value, to assess the conservation priority of 300 species of plants and animals in Florida given projections of climate change, human land-use patterns, and sea level rise by the year 2100. We account for multiple sources of uncertainty and prioritize species under five different systems of value, ranging from a primary emphasis on vulnerability to threats to an emphasis on metrics of conservation value such as phylogenetic distinctiveness. Our results reveal remarkable consistency in the prioritization of species across different conservation value systems. Species of high priority include the Miami blue butterfly (Cyclargus thomasi bethunebakeri), Key tree cactus (Pilosocereus robinii), Florida duskywing butterfly (Ephyriades brunnea floridensis), and Key deer (Odocoileus virginianus clavium). We also identify sources of uncertainty and the types of life history information consistently missing across taxonomic groups. This study characterizes the vulnerabilities to major threats of a broad swath of Florida's biodiversity and provides a system for prioritizing conservation efforts that is quantitative, flexible, and free from hidden value judgments.

  12. Using GRACE and Landsat imagery to assess water balance change due to anthropogenic modification and climate change in the Aral Sea region: 2002-2012

    NASA Astrophysics Data System (ADS)

    Zmijewski, K. A.; Becker, R.

    2012-12-01

    The Aral Sea watershed located in central Asia has seen significant anthropogenic modification since the mid 20th century, leading to the desiccation of the Aral Sea. The Aral Sea is a closed basin with a watershed area of almost 2 million square kilometers including the Amu Darya and Syr Darya river systems. A network of canals and channels has diverted a significant amount of flow from both rivers into various agricultural areas and reservoirs. Monitoring water resources within the region is of utmost importance to understanding how the region will be impacted by ongoing and future climate change. Using GRACE (Gravity and Climate Experiment) data from 2002-2012 water storage trends within the basin were determined using a linear model. The data was normalized and fit with an annual function to determine inter-annual variability. Anthropogenic modification has lead to increased water storage in the central region of both watersheds, most notably within the Aydar-Arnasay lakes after the Shadara irrigation dam was built in the 1960s. Gravity data within this region shows a positive trend of increased storage: 0.30 to 0.40 mm (equivalent water thickness) per year. However, the Aral Sea basin proper showed a negative trend of almost 1 mm (equivalent water thickness) per year. The entire watershed and basin showed an overall negative trend in water storage. To determine the possible cause of climate on these changes, 206 weather stations within the basin were analyzed for climate trends (precipitation and temperature). No significant trends were observed in basin-wide precipitation and average annual temperatures increased 1-2 degrees C over a century. Precipitation in close proximity to the Aral Sea showed a significant decrease after 1970. The effects of anthropogenic modification and climate trends on water surface area were determined using MODIS land use classifications (MCD12Q1) from 2001-2010, supplemented with Landsat imagery. Water surface area totals within

  13. Plio-Pleistocene climate change in Asian: Evidence from terrestrial lipids at ODP Site 1143 in the South China Sea

    NASA Astrophysics Data System (ADS)

    Li, L.; Wang, H.; Wang, P.

    2010-12-01

    A homologous series of n-alkanes (C24-C35) were detected at the ODP site 1143 (9°21.72'N, 113°17.11'E) in southern South China Sea and were used to reconstruct the paleoclimate change in the eastern Asian over the past 5Ma. Strong odd-carbon number predominance with a maximum at C29 or C31 in these n-alkanes indicated their origins of terrestrial higher plant waxes, which are transported to the deep sea mainly by rivers. In general, the profile of ΣAlkanes (sum of C24-C35) can be subdivided into two time intervals: Before 2.7 Ma, the ΣAlkanes fluctuated between 100 and 500 ng/g, averaging at 250 ng/g, which was lower than that in late Pleistocene but higher than that in early Pleistocene. Highland sea level during this period might have caused the deposition of the ΣAlkanes, which reflected the riverine discharge and rainfall intensity . After 2.7Ma, ΣAlkanes varied between 80-750 ng/g, with big fluctuations in the late Pleistocene. Alkane abundances depict a robust positive relationship with δ18OG. ruber but inverse relationship with temperature with maximum concentrations corresponding to heavier δ18OG. rube and lower temperature during glacial periods. This related to the changes in flux of the materials transported by the river, which, in turn, would have been influenced by sea level and/or precipitation. During glacial low stands of sea-levels, especially in the late Pleistocene, the emergence of the huge continental platforms in the south of the SCS led to the development of numerous drainage systems that significantly increased the input of terrestrial material and thus n-alkanes contents. Besides ΣAlkanes, the alkane indices, i.e. the ratio of n-C31 /n-C27 and average carbon chain lengths (ACLs) of odd carbon-number, also recorded the palaeoenvironment and palaeoclimate changes. Although studies show that plants tend to synthesize longer chain length n-alkanes in response to elevated temperature and/or aridity, the higher n-C31 /n-C27 and ACLs in

  14. Analysis of a Storm-induced Surge Anomaly Under Climate Change with Focus on Sea Level Rise

    NASA Astrophysics Data System (ADS)

    Hagen, S. C.; Bilskie, M. V.

    2014-12-01

    The impact of sea level rise (SLR) on hurricane storm surge and wind-waves is a non-linear process (Bilskie et al., 2014). Using a high-resolution physics-based numerical model, we examine shelf wave dynamics in general and a shelf anomaly in particular under global climate change scenarios, which include SLR and potential hurricane intensification. To begin it is noted that Hurricane Dennis (2005) produced local storm surge in Apalachee Bay of six to ten feet, but the National Hurricane Center advisory for the region forecast only four to six feet of storm surge. This forecast was based on the relatively weak wind forcing along the west Florida shelf, but the additional storm-induced surge was caused by a remotely forced shelf wave that propagated along the Florida shelf as a topographic Rossby wave (Morey et al.,2006).These mesoscale processed are studied under climate change scenarios using a state-of-the-art wind-waved hurricane storm surge model (SWAN+ADCIRC) of the northern Gulf of Mexico that encompasses the off-shore regions including the western North Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. The finitie element model penetrates the shoreline along Florida's "Big Bend" region, the Florida panhandle, Alabama, and the Mississippi coast with high resolution that is sufficient to describe the Gulf Intracoastal Waterway, for example. The large domain and fine mesh resolution included in the model permits the description, and non-linear interaction, of the physics associated with wind-generated waves and hurricane storm surge that produce storm-induced anomalies such as the Rossby wave generated during Hurricane Dennis. Examination of various wave statistics such as significant wave height, mean wave period and direction, and wave radiation stress gradients provide insight into future behavior of storm-induced shelf wave dynamics under global climate change scenarios. This study may impact future statistics and probability distributions for analysis of

  15. A stable, unbiased, long-term satellite based data record of sea surface temperature from ESA's Climate Change Initiative

    NASA Astrophysics Data System (ADS)

    Rayner, Nick; Good, Simon; Merchant, Chris

    2013-04-01

    The study of climate change demands long-term, stable observational records of climate variables such as sea surface temperature (SST). ESA's Climate Change Initiative was set up to unlock the potential of satellite data records for this purpose. As part of this initiative, 13 projects were established to develop the data records for different essential climate variables - aerosol, cloud, fire, greenhouse gases, glaciers, ice sheets, land cover, ocean colour, ozone, sea ice, sea level, soil moisture and SST. In this presentation we describe the development work that has taken place in the SST project and present new prototype data products that are available now for users to trial. The SST project began in 2010 and has now produced two prototype products. The first is a long-term product (covering mid-1991 - 2010 currently, but with a view to update this in the future), which prioritises length of data record and stability over other considerations. It is based on data from the Along-Track Scanning Radiometer (ATSR) and Advanced Very-High Resolution Radiometer (AVHRR) series of satellite instruments. The product aims to combine the favourable stability and bias characteristics of ATSR data with the geographical coverage achieved with the AVHRR series. Following an algorithm selection process, an optimal estimation approach to retrieving SST from the satellite measurements from both sensors was adopted. The retrievals do not depend on in situ data and so this data record represents an independent assessment of SST change. In situ data are, however, being used to validate the resulting data. The second data product demonstrates the coverage that can be achieved using the modern satellite observing system including, for example, geostationary satellite data. Six months worth of data have been processed for this demonstration product. The prototype SST products will be released in April to users to trial in their work. The long term product will be available as

  16. Surviving rapid climate change in the deep sea during the Paleogene hyperthermals.

    PubMed

    Foster, Laura C; Schmidt, Daniela N; Thomas, Ellen; Arndt, Sandra; Ridgwell, Andy

    2013-06-01

    Predicting the impact of ongoing anthropogenic CO2 emissions on calcifying marine organisms is complex, owing to the synergy between direct changes (acidification) and indirect changes through climate change (e.g., warming, changes in ocean circulation, and deoxygenation). Laboratory experiments, particularly on longer-lived organisms, tend to be too short to reveal the potential of organisms to acclimatize, adapt, or evolve and usually do not incorporate multiple stressors. We studied two examples of rapid carbon release in the geological record, Eocene Thermal Maximum 2 (∼53.2 Ma) and the Paleocene Eocene Thermal Maximum (PETM, ∼55.5 Ma), the best analogs over the last 65 Ma for future ocean acidification related to high atmospheric CO2 levels. We use benthic foraminifers, which suffered severe extinction during the PETM, as a model group. Using synchrotron radiation X-ray tomographic microscopy, we reconstruct the calcification response of survivor species and find, contrary to expectations, that calcification significantly increased during the PETM. In contrast, there was no significant response to the smaller Eocene Thermal Maximum 2, which was associated with a minor change in diversity only. These observations suggest that there is a response threshold for extinction and calcification response, while highlighting the utility of the geological record in helping constrain the sensitivity of biotic response to environmental change. PMID:23690593

  17. Shading and Watering as a Tool to Mitigate the Impacts of Climate Change in Sea Turtle Nests

    PubMed Central

    Hill, Jacob E.; Paladino, Frank V.; Spotila, James R.; Tomillo, Pilar Santidrián

    2015-01-01

    Increasing sand temperatures resulting from climate change may negatively impact sea turtle nests by altering sex ratios and decreasing reproductive output. We analyzed the effect of nest shading and watering on sand temperatures as climate mitigation strategies in a beach hatchery at Playa Grande, Costa Rica. We set up plots and placed thermocouples at depths of 45cm and 75cm. Half of the plots were shaded and half were exposed to the sun. Within these exposure treatments, we applied three watering treatments over one month, replicating local climatic conditions experienced in this area. We also examined gravimetric water content of sand by collecting sand samples the day before watering began, the day after watering was complete, and one month after completion. Shading had the largest impact on sand temperature, followed by watering and depth. All watering treatments lowered sand temperature, but the effect varied with depth. Temperatures in plots that received water returned to control levels within 10 days after watering stopped. Water content increased at both depths in the two highest water treatments, and 30 days after the end of water application remained higher than plots with low water. While the impacts of watering on sand temperature dissipate rapidly after the end of application, the impacts on water content are much more lasting. Although less effective at lowering sand temperatures than shading, watering may benefit sea turtle clutches by offsetting negative impacts of low levels of rain in particularly dry areas. Prior to implementing such strategies, the natural conditions at the location of interest (e.g. clutch depth, environmental conditions, and beach characteristics) and natural hatchling sex ratios should be taken into consideration. These results provide insight into the effectiveness of nest shading and watering as climate mitigation techniques and illustrate important points of consideration in the crafting of such strategies. PMID

  18. Shading and watering as a tool to mitigate the impacts of climate change in sea turtle nests.

    PubMed

    Hill, Jacob E; Paladino, Frank V; Spotila, James R; Tomillo, Pilar Santidrián

    2015-01-01

    Increasing sand temperatures resulting from climate change may negatively impact sea turtle nests by altering sex ratios and decreasing reproductive output. We analyzed the effect of nest shading and watering on sand temperatures as climate mitigation strategies in a beach hatchery at Playa Grande, Costa Rica. We set up plots and placed thermocouples at depths of 45 cm and 75 cm. Half of the plots were shaded and half were exposed to the sun. Within these exposure treatments, we applied three watering treatments over one month, replicating local climatic conditions experienced in this area. We also examined gravimetric water content of sand by collecting sand samples the day before watering began, the day after watering was complete, and one month after completion. Shading had the largest impact on sand temperature, followed by watering and depth. All watering treatments lowered sand temperature, but the effect varied with depth. Temperatures in plots that received water returned to control levels within 10 days after watering stopped. Water content increased at both depths in the two highest water treatments, and 30 days after the end of water application remained higher than plots with low water. While the impacts of watering on sand temperature dissipate rapidly after the end of application, the impacts on water content are much more lasting. Although less effective at lowering sand temperatures than shading, watering may benefit sea turtle clutches by offsetting negative impacts of low levels of rain in particularly dry areas. Prior to implementing such strategies, the natural conditions at the location of interest (e.g. clutch depth, environmental conditions, and beach characteristics) and natural hatchling sex ratios should be taken into consideration. These results provide insight into the effectiveness of nest shading and watering as climate mitigation techniques and illustrate important points of consideration in the crafting of such strategies.

  19. Temperature, but not pH, compromises sea urchin fertilization and early development under near-future climate change scenarios

    PubMed Central

    Byrne, Maria; Ho, Melanie; Selvakumaraswamy, Paulina; Nguyen, Hong D.; Dworjanyn, Symon A.; Davis, Andy R.

    2009-01-01

    Global warming is causing ocean warming and acidification. The distribution of Heliocidaris erythrogramma coincides with the eastern Australia climate change hot spot, where disproportionate warming makes marine biota particularly vulnerable to climate change. In keeping with near-future climate change scenarios, we determined the interactive effects of warming and acidification on fertilization and development of this echinoid. Experimental treatments (20–26°C, pH 7.6–8.2) were tested in all combinations for the ‘business-as-usual’ scenario, with 20°C/pH 8.2 being ambient. Percentage of fertilization was high (>89%) across all treatments. There was no difference in percentage of normal development in any pH treatment. In elevated temperature conditions, +4°C reduced cleavage by 40 per cent and +6°C by a further 20 per cent. Normal gastrulation fell below 4 per cent at +6°C. At 26°C, development was impaired. As the first study of interactive effects of temperature and pH on sea urchin development, we confirm the thermotolerance and pH resilience of fertilization and embryogenesis within predicted climate change scenarios, with negative effects at upper limits of ocean warming. Our findings place single stressor studies in context and emphasize the need for experiments that address ocean warming and acidification concurrently. Although ocean acidification research has focused on impaired calcification, embryos may not reach the skeletogenic stage in a warm ocean. PMID:19324767

  20. Late Pleistocene to Holocene paleoceanographic and paleo-climatic changes in Gulf of Gemlik, Sea of Marmara, Turkey

    NASA Astrophysics Data System (ADS)

    Filikci, Betül; Kadir Eriş, K.; Namık Çaǧatay, M.; Gasperini, Luca; Sabuncu, Asen; Acar, Dursun; Yalamaz, Burak

    2016-04-01

    Gulf of Gemlik is an east-west oriented marine inlet with a maximum depth of 113 m in the south-eastern part of the Sea of Marmara. It is located on the middle branch of the North Anatolian Fault Zone. While the Gulf of Gemlik is separated from the SoM by a bedrock sill at -50 m, there were presumably several disconnections during the Late Pleistocene to Holocene, but the timing of the youngest connection around the onset of the Holocene is still controversial. Here, we attempt to elucidate the paleoceanographic and paleoenvironmental changes during the late glacial-Holocene using the multi-proxy analysis of a core extending back to 13 ka BP. The multi-proxy data include physical and geochemical properties together with AMS 14C ages. The core sediments covering the time period of the last 13 ka BP consists of two main lithostratigraphic units. The lower Unit L2 represents the lacustrine phase of the gulf prior to 10.6 ka BP, while the upper Unit L1 is an overlying transgressive mud drape deposited during the main part of the Holocene. Unit L2 deposited prior 10.6 ka BP represents Bølling-Allerød and Younger Dryas climatic periods, when prograding shelf edge sediments were deposited in the form of well sorted medium sands with brackish water bivalve shells (Dreissenapolymorpha). At the beginning of the Holocene, the rising sea level in the Sea of Marmara breached the -50 m sill at 10.6 ka BP, and therefore the Gulf of Gemlik was converted into a marine realm. Soon after, the water stratifications allowed to the formation of the previously studied two sapropels in the gulf, as shown by increased TOC contents. μ-XRF Ca/Ti and Sr/Ca profiles of Unit L1 provide evidence of rapid climatic changes at 8.2 ka BP and 4.2 ka BP, representing cold and dry short climatic periods which are well correlated with previous marine and lake studies in İznik Lake south of the Sea of Marmara. Keywords: Gemlik Gulf, core, paleoclimate, Late Pleistocene to Holocene

  1. Projecting future wave climates and corresponding shoreline changes along the differently exposed coastal sections of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Suursaar, Ülo; Tõnisson, Hannes

    2015-04-01

    The aim of the study is to analyze the recently observed and projected future coastal changes in differently exposed Estonian coastal sections as a result of changing wind and wave climates. Along the shoreline of the practically tideless Baltic Sea, the increase in storminess has already impacted the coastal environment over the last 50 years. However, the number of storms, as well as their pathways, has been fluctuating considerably over the last decades. Furthermore, forecasting future hydrodynamic conditions and corresponding coastal changes is a rather mixed, yet crucial task. A number of Estonian study sites have been regularly examined by coastal scientists since the 1960s. Six coastal sections have been chosen for this study: Harilaid Peninsula (exposed to SW), Letipea-Sillamäe (N), Kõiguste-Nasva (SE), Kihnu-Pärnu (S), and two sides of the Osmussaar Island (W, N). Since the 2000s, use of GPS instruments and GIS software has enabled year-to-year changes in the shoreline to be tracked and the calculation of the corresponding areas or volumes due to accumulation and erosion. Recently digitized aerial photographs, as well as orthophotos and old topographic maps, enable the calculation of changes over longer sub-periods. Based on recorded and hindcasted changes in wind-driven hydrodynamic conditions, we found relationships between forcing conditions and the rates at which shorelines were changing. For future changes, wave climates were projected for the selected coastal sections of special geomorphic interest, where also a series of hydrodynamic surveys (waves, currents, sea level) were carried out using ADCP-s in 2006-2014. Wave parameters were consecutively hindcasted using a site-dependently calibrated fetch-based wave model. As the full calculation period (1966-2013) might suffer from inhomogeneity of wind input data, a confidently homogeneous time cut (2004-2013; 10 full years with hourly resolution) was chosen as a baseline (or control) period. An

  2. Paleoceanographic conditions in the western Bering Sea as a response to global sea level changes and remote climatic signals during the last 180 kyr

    NASA Astrophysics Data System (ADS)

    Ovsepyan, E. A.; Ivanova, E. V.; Gulev, S. K.

    2016-06-01

    We present results from the sediment core SO201-2-85KL retrieved from the western Bering Sea that recovered the past 180 000 years. For the first time, the intense dissolution of calcareous microfossils has been established when the Bering Strait was open during the glacioeustatic sea level rise. Possible mechanisms of climatic teleconnections between remote regions are considered.

  3. Scenario analysis on protein consumption and climate change effects on riverine N export to the Baltic Sea.

    PubMed

    Eriksson Hägg, Hanna; Humborg, Christoph; Mörth, Carl-Magnus; Medina, Miguel Rodriguez; Wulff, Fredrik

    2010-04-01

    This paper evaluates possible future nitrogen loadings from 105 catchments surrounding the Baltic Sea. Multiple regressions are used to model total nitrogen (TN) flux as a function of specific runoff (Q), atmospheric nitrogen deposition, and primary emissions (PE) from humans and livestock. On average cattle contributed with 63%, humans with 20%, and pigs with 17% of the total nitrogen PE to land. Compared to the reference period (1992-1996) we then evaluated two types of scenarios for year 2070. i) An increased protein consumption scenario that led to 16% to 39% increased mean TN flux (kg per km(-2)). ii) Four climate scenarios addressing effects of changes in river discharge. These scenarios showed increased mean TN flux from the northern catchments draining into the Gulf of Bothnia (34%) and the Gulfs of Finland and Riga (14%), while the mean TN flux decreased (-27%) for catchments draining to the Baltic Proper. However, the net effect of the scenarios showed a possible increase in TN flux ranging from 3-72%. Overall an increased demand for animal protein will be instrumental for the Baltic Sea ecosystem and may be a major holdback to fulfill the environmental goals of the Baltic Sea Action Plan. PMID:20230019

  4. How to preserve coastal wetlands, threatened by climate change-driven rises in sea level.

    PubMed

    Ivajnšič, Danijel; Kaligarič, Mitja

    2014-10-01

    A habitat transition model, based on the correlation between individual habitats and micro-elevation intervals, showed substantial changes in the future spatial distributions of coastal habitats. The research was performed within two protected areas in Slovenia: Sečovlje Salina Nature Park and Škocjan Inlet Nature Reserve. Shifts between habitats will occur, but a general decline of 42 % for all Natura 2000 habitats is projected by 2060, according to local or global (IPCC AR4) sea level rise predictions. Three different countermeasures for the long-term conservation of targeted habitat types were proposed. The most "natural" is displacement of coastal habitats using buffer zones (1) were available. Another solution is construction of artificial islets, made of locally dredged material (2); a feasible solution in both protected areas. Twenty-two islets and a dried salt pan zone at the desired elevations suitable for those habitats that have been projected to decease in area would offer an additional 10 ha in the Sečovlje Salina. Twenty-one islets and two peninsulas at two different micro-altitudes would ensure the survival of 13 ha of three different habitats. In the area of Sečovlje Salina, abandoned salt pans could be terrestrialized by using permanent, artificial sea barriers, in a manner close to poldering (3). By using this countermeasure, another 32 ha of targeted habitat could be preserved. It can be concluded that, for each coastal area, where wetland habitats will shrink, strategic plans involving any of the three solutions should be prepared well in advance. The specific examples provided might facilitate adaptive management of coastal wetlands in general.

  5. Climate change influences on environment as a determinant of Indigenous health: Relationships to place, sea ice, and health in an Inuit community.

    PubMed

    Durkalec, Agata; Furgal, Chris; Skinner, Mark W; Sheldon, Tom

    2015-07-01

    This paper contributes to the literature on Indigenous health, human dimensions of climate change, and place-based dimensions of health by examining the role of environment for Inuit health in the context of a changing climate. We investigated the relationship between one key element of the environment - sea ice - and diverse aspects of health in an Inuit community in northern Canada, drawing on population health and health geography approaches. We used a case study design and participatory and collaborative approach with the community of Nain in northern Labrador, Canada. Focus groups (n = 2), interviews (n = 22), and participant observation were conducted in 2010-11. We found that an appreciation of place was critical for understanding the full range of health influences of sea ice use for Inuit. Negative physical health impacts were reported on less frequently than positive health benefits of sea ice use, which were predominantly related to mental/emotional, spiritual, social, and cultural health. We found that sea ice means freedom for sea ice users, which we suggest influences individual and collective health through relationships between sea ice use, culture, knowledge, and autonomy. While sea ice users reported increases in negative physical health impacts such as injuries and stress related to changing environmental conditions, we suggest that less tangible climate change impacts related to losses of health benefits and disruptions to place meanings and place attachment may be even more significant. Our findings indicate that climate change is resulting in and compounding existing environmental dispossession for Inuit. They also demonstrate the necessity of considering place meanings, culture, and socio-historical context to assess the complexity of climate change impacts on Indigenous environmental health.

  6. Smithsonian climate change exhibits

    NASA Astrophysics Data System (ADS)

    Kumar, Mohi

    2006-05-01

    Two new museum exhibits, ``Arctic: A Friend Acting Strangely'' and ``Atmosphere: Change is in the Air'' opened 15 April at the Smithsonian Institution's National Museum of Natural History in Washington, D.C., in partnership with the U.S. National Oceanic and Atmospheric Administration, NASA, and the U.S. National Science Foundation. In ``Arctic: A Friend Acting Strangely,'' anecdotes from indigenous polar people reveal how climate changes have affected life within the last 50 years. For example, as permafrost melts and sea ice shrinks, plant distributions and animal migration patterns are changing, severely affecting culture.

  7. Development of small carbonate banks on the south Florida platform margin: Response to sea level and climate change

    USGS Publications Warehouse

    Mallinson, David J.; Hine, Albert C.; Hallock, Pamela; Locker, Stanley D.; Shinn, Eugene; Naar, David; Donahue, Brian; Weaver, Douglas C.

    2003-01-01

    Geophysical and coring data from the Dry Tortugas, Tortugas Bank, and Riley’s Hump on the southwest Florida margin reveal the stratigraphic framework and growth history of these carbonate banks. The Holocene reefs of the Dry Tortugas and Tortugas Bank are approximately 14 and 10 m thick, respectively, and are situated upon Pleistocene reefal edifices. Tortugas Bank consists of the oldest Holocene corals in the Florida Keys with earliest coral recruitment occurring at ∼9.6 cal ka. Growth curves for the Tortugas Bank reveal slow growth (<1 mm/yr) until 6.2 cal ka, then a rapid increase to 3.4 mm/yr, until shallow reef demise at ∼4.2 cal ka. Coral reef development at the Dry Tortugas began at ∼6.4 cal ka. Aggradation at the Dry Tortugas was linear, and rapid (∼3.7 mm/yr) and kept pace with sea-level change. The increase in aggradation rate of Tortugas Bank at 6.2 cal ka is attributed to the growth of the Dry Tortugas reefs, which formed a barrier to inimical shelf water. Termination of shallow (<15 m below sea level) reef growth at Tortugas Bank at ∼4.2 cal ka is attributed to paleoclimate change in the North American interior that increased precipitation and fluvial discharge. Reef growth rates and characteristics are related to the rate of sea-level rise relative to the position of the reef on the shelf margin, and are additionally modified by hydrographic conditions related to climate change.

  8. Prospects of the New Science and Outreach Network Baltic Earth with Results of the Second Climate Change Assessment for the Baltic Sea Region (BACC II)

    NASA Astrophysics Data System (ADS)

    Reckermann, M.; Von Storch, H.; Omstedt, A. T.; Meier, M.; Rutgersson, A.

    2014-12-01

    The Baltic Sea region in Northern Europe spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It represents an old cultural landscape, and the Baltic Sea itself is among the most intensively studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. A major outcome of Baltic Earth will be the update of the BALTEX Assessment of Climate Change for the Baltic Sea Basin (BACC II). This new study after 5 years finds the results of BACC I still valid. Climate change can be detected at the regional scale but attribution is still weak. The effect of changing atmospheric aerosol loads and land use change is largely unknown so far and needs further attention in the coming years. For the observed changes in biogeochemical and ecological systems, multiple drivers are at work of which climate change is one. Their relative importance still needs to be evaluated. When addressing climate change impacts on e.g. forestry, agriculture, urban

  9. A Pluridisciplinary Study of the Impact of Future Ice Sheets Instability on Sea Level Rise, Climate Changes, Migrations and Energy Supply

    NASA Astrophysics Data System (ADS)

    Ramstein, G.; Defrance, D.; Dumas, C.; Charbit, S.; Gemenne, F.; Vanderlinden, J. P.; Bouneau, S.; David, S.

    2014-12-01

    From paleoclimate data and GCM models simulations, we learnt that, when ice sheets are unstable, they produce large surges of icebergs that cover North Atlantic and produce global climate instability through atmosphere and ocean dynamics. Indeed, these instabilities are associated with a cold (glacial) context. In a warming world, it appears that the two remaining ice sheets (Antarctica and Greenland) are becoming unstable. The probability of abrupt ice sheet changes is therefore to be investigated. In comparison with predicted AR5 sea level rise (SLR) (28 to 82 cm), such a fast melting could add a contribution of 2 to 5 meters, which corresponds to the sea level rise estimate of glacial instability (Heinrich events). The aim of this presentation is to describe consistent sea level and climate simulations. We define 3 scenarios, the sea level rise is produced by the melting of about third of the Greenland, or the disappearance of West Antarctica, or finally a mixture of both ice sheets melting. We first analyze, using IPSL OAGCM, the climatic impact. Indeed, superimposed to direct sea level rise, climate changes has drastic consequences in North Atlantic (Europe and east of North America) due to the thermohaline circulation breakdown. Moreover, when freshwater is injected into North Atlantic, far field effects on the location and amplitude of Asian Monsoon have been shown with its drastic decrease. The second step of this multidisciplinary study is to quantify the impact of the sea level rise and the climatic changes on populations migration, with a focus on Southern Asia with a prospective migration of several hundreds of people. In a third step, we intend to simulate the reorganization of power supply to adapt to the expected new distribution of population, using a quantitative energy model (COSIME). Here, we show the climate response to the 3 investigated climate scenarios and the response in terms of migration, which is huge due to the very large part of the

  10. Downslope strengthening millennial-scale climatic change signals deduced from high-resolution clay mineralogy during the last glaciation in the northern South China Sea

    NASA Astrophysics Data System (ADS)

    Zhao, S.; Liu, Z.; Wang, X.; Xie, X.; Shi, J.; Christophe, C.

    2015-12-01

    Clay mineralogy provides a powerful tool to reconstruct glacial-cyclic paleoceanographic and paleoclimatic changes in the South China Sea. However, whether the clay mineralogy could also reserve millennial-scale climatic change is still poorly understood, because clay minerals usually produced through the long-term chemical weathering are not sensitive to the fast environmental change. This study presents the high-resolution clay mineralogy of three high-quality sediment cores, which were retrieved from a transect on the continental slope of the northern South China Sea during the cruise of MD190 (2012). Our results show that time series changes of clay mineral assemblages display a clear occurrence of millennial-scale climatic change events, such as Younger Dryas, Bolling-Allerod, and Heinrich events 1-6. The reconstructed relative contributions of clay minerals from their source areas of Taiwan and Luzon are closely related to the millennial-scale climatic changes, while the clay mineral contribution from the source area of the Pearl River presents a relationship to the sea level change. Following the transect with increasing water depths, the Pearl River contribution decreases, whereas the Taiwan and Luzon contributions present more complex changes, and the millennial-scale climatic change signals are also gradually strengthened. The Luzon/Taiwan contribution ratio is used for the proxy of the millennial-scale paleoclimate evolution. The lower ratio presents colder events, while the high ratio indicates warmer periods. The distinct downslope strengthening millennial-scale climatic change indicates that deepwater sediments in the South China Sea could well reserve fast climatic change events that usually occurred in high latitudes.

  11. Modelling the influence of climate change on the chemical concentrations in the Baltic Sea region with the POPCYCLING-Baltic model.

    PubMed

    Kong, Deguo; MacLeod, Matthew; Cousins, Ian T

    2014-09-01

    The effect of projected future changes in temperature, wind speed, precipitation and particulate organic carbon on concentrations of persistent organic chemicals in the Baltic Sea regional environment is evaluated using the POPCYCLING-Baltic multimedia chemical fate model. Steady-state concentrations of hypothetical perfectly persistent chemicals with property combinations that encompass the entire plausible range for non-ionizing organic substances are modelled under two alternative climate change scenarios (IPCC A2 and B2) and compared to a baseline climate scenario. The contributions of individual climate parameters are deduced in model experiments in which only one of the four parameters is changed from the baseline scenario. Of the four selected climate parameters, temperature is the most influential, and wind speed is least. Chemical concentrations in the Baltic region are projected to change by factors of up to 3.0 compared to the baseline climate scenario. For chemicals with property combinations similar to legacy persistent organic pollutants listed by the Stockholm Convention, modelled concentration ratios between two climate change scenarios and the baseline scenario range from factors of 0.5 to 2.0. This study is a first step toward quantitatively assessing climate change-induced changes in the environmental concentrations of persistent organic chemicals in the Baltic Sea region.

  12. Current Climate Variability & Change

    NASA Astrophysics Data System (ADS)

    Diem, J.; Criswell, B.; Elliott, W. C.

    2013-12-01

    climate change. The next section guides students through the exploration of temporal changes in global temperature from the surface to the lower stratosphere. Students discover that there has been global warming over the past several decades, and the subsequent section allows them to consider solar radiation and greenhouse gases as possible causes of this warming. Students then zoom in on different latitudinal zones to examine changes in temperature for each zone and hypothesize about why one zone may have warmed more than others. The final section, prior to the answering of the essential questions, is an examination of the following effects of the current change in temperatures: loss of sea ice; rise of sea level; loss of permafrost loss; and moistening of the atmosphere. The lab addresses 14 climate-literacy concepts and all seven climate-literacy principles through data and images that are mainly NASA products. It focuses on the satellite era of climate data; therefore, 1979 is the typical starting year for most datasets used by students. Additionally, all time-series analysis end with the latest year with full-year data availability; thus, the climate variability and trends truly are 'current.'

  13. Climate-induced variations in lake levels: A mechanism for short-term sea level change during non-glacial times

    SciTech Connect

    Jacobs, D. ); Sahagian, D. . Dept of Geological Sciences)

    1992-01-01

    Variations in insolation due to periodic orbital parameters can cause climatic changes and associated variations in the intensity of monsoonal circulation. This can lead to significant variations in the levels of internally draining lakes on timescales of 10,000 to 100,000 years in regions affected by the monsoon (20,000 years for orbital precession). These variations may be responsible for small scale (few meters) eustatic sea level changes in an ice-free Earth, and may contribute to sea level changes in the presence of ice as well. The authors have estimated the volume of empty present lake basins in the regions of Asia and North Africa influenced by the monsoon. The surface water volume alone of these basins is equivalent to a two meter difference in sea level, but is considerably augmented by groundwater associated with an increase in lake level. The lake variation mechanism for sea level change has its basis in the Quaternary record of climate change and associated explanatory models. However, the argument also applies to earlier, non-glacial periods of geologic time. Clear evidence for the presence of ice in the Triassic is lacking. However, there is evidence for short-term periodic fluctuations of lake levels as well as sea level during that time. These sea level changes, as well as those in the Devonian, Jurassic, and Cretaceous, may be driven by periodic fluctuation in lacustrine and groundwater storage resulting from orbitally forced changes in monsoon intensity, even in the absence of significant glacial ice.

  14. Sea level projections to AD2500 with a new generation of climate change scenarios

    NASA Astrophysics Data System (ADS)

    Jevrejeva, S.; Moore, J. C.; Grinsted, A.

    2012-01-01

    Sea level rise over the coming centuries is perhaps the most damaging side of rising temperature (Anthoff et al., 2009). The economic costs and social consequences of coastal flooding and forced migration will probably be one of the dominant impacts of global warming (Sugiyama et al., 2008). To date, however, few studies (Nicholls et al., 2008; Anthoff et al., 2009) on infrastructure and socio-economic planning include provision for multi-century and multi-metre rises in mean sea level. Here we use a physically plausible sea level model constrained by observations, and forced with four new Representative Concentration Pathways (RCP) radiative forcing scenarios (Moss et al., 2010) to project median sea level rises of 0.57 for the lowest forcing and 1.10 m for the highest forcing by 2100 which rise to 1.84 and 5.49 m respectively by 2500. Sea level will continue to rise for several centuries even after stabilisation of radiative forcing with most of the rise after 2100 due to the long response time of sea level. The rate of sea level rise would be positive for centuries, requiring 200-400 years to drop to the 1.8 mm/yr 20th century average, except for the RCP3PD which would rely on geoengineering.

  15. On assessment of the relationship between changes of sea ice extent and climate in the Arctic

    NASA Astrophysics Data System (ADS)

    Alekseev, Genrikh; Glok, Natalia; Smirnov, Alexander

    2016-04-01

    An increase of surface air temperature (SAT) in the marine Arctic (a part of the Arctic covered with sea ice in winter) shows a good relationship with reduction of sea ice extent (SIE) in summer. For instance, a strong correlation (a coefficient equal to -0.93) was found between the summer SAT in the marine Arctic and satellite-derived 1980-2014 September sea ice index (the average of sea ice extent in the Arctic since 1978, in millions of sq. km). Based on this finding anomalies of Arctic September SIE were reconstructed from the beginning of twentieth century using linear regression relationship. This reconstructed SIE shows a substantial decrease in the 1930-40s with a minimum occurring in 1936, which, however, is only a half of the decline in 2012. An impact of the inflow of warm and salty Atlantic water on winter SIE was evaluated as an example for the Barents Sea. This evaluation reveals a coherent spatial pattern of the Atlantic water spreading, presented by surface salinity distribution, and the position of sea-ice edge, and significant correlation between the inflow of the Atlantic water and maximal SIE.

  16. What Is Climate Change? (Environmental Health Student Portal)

    MedlinePlus

    ... vs Climate Change Global Warming (National Ocean and Atmospheric Administration) - Introduction to global warming with links to greenhouse effect, sea levels, and future climate change. Games and ...

  17. Alluvial deposition and lake-level fluctuations forced by Late Quaternary climate change: the Dead Sea case example

    NASA Astrophysics Data System (ADS)

    Klinger, Y.; Avouac, J. P.; Bourles, D.; Tisnerat, N.

    2003-11-01

    Based on geomorphic observations, we discuss lake-level fluctuations, alluvial deposition and river entrenchment in the Dead Sea-Wadi Araba area. The bulk of alluvium in the northern Wadi Araba was probably deposited before the Lisan period of lake transgression that started at about 70 kyears B.P. The lake reached a maximum elevation about 150 m below sea level (b.s.l.), possibly around 15 cal. kyears B.P. as indicated by the highest preserved beach ridges. Cosmogenic exposure dates show that the ridge material consists mainly of remobilized Pleistocene gravel indicating little sediment supply during most of the Lisan period. During this period, a reduced sediment flux fed subaquatic fan deltas along the margin of the Dead Sea. Wetter conditions settled at the end of this period, the water level rose to about 280 m b.s.l. around 15 kyears B.P. and prevailed in the early Holocene (10.5-7 cal. kyears B.P.). Following that humid period, the lake level dropped and two major episodes of fluvial aggradation occurred during periods of relative low lake level. The first aggradational episode took place between about 7.0 and 6.2 cal. kyears B.P. Beach bars indicate a subsequent lake transgression between 6.2 and 4.4 kyears B.P. up to 350 m b.s.l. The second aggradational episode happened between 4.4 and 2.0 cal. kyears B.P., and was also followed by a late transgression up to 375 m b.s.l., dated to 1960-1715 cal. years B.P. The correlation between low lake level and fluvial aggradation is taken to reflect the synchronous change of the fluvial regime and of the lake hydrologic balance, forced by climate changes, rather than a base-level control. We also exclude large tectonic forcing on fan emplacement and river entrenchment. Alluviation appears in this setting as a very irregular process, characterized by long periods of quiescence alternating with periods of fan build-up, reflecting the transient response of the water drainage system to climate change.

  18. Future climate change driven sea-level rise: secondary consequences from human displacement for island biodiversity.

    PubMed

    Wetzel, Florian T; Kissling, W Daniel; Beissmann, Helmut; Penn, Dustin J

    2012-09-01

    Sea-level rise (SLR) due to global warming will result in the loss of many coastal areas. The direct or primary effects due to inundation and erosion from SLR are currently being assessed; however, the indirect or secondary ecological effects, such as changes caused by the displacement of human populations, have not been previously evaluated. We examined the potential ecological consequences of future SLR on >1,200 islands in the Southeast Asian and the Pacific region. Using three SLR scenarios (1, 3, and 6 m elevation, where 1 m approximates most predictions by the end of this century), we assessed the consequences of primary and secondary SLR effects from human displacement on habitat availability and distributions of selected mammal species. We estimate that between 3-32% of the coastal zone of these islands could be lost from primary effects, and consequently 8-52 million people would become SLR refugees. Assuming that inundated urban and intensive agricultural areas will be relocated with an equal area of habitat loss in the hinterland, we project that secondary SLR effects can lead to an equal or even higher percent range loss than primary effects for at least 10-18% of the sample mammals in a moderate range loss scenario and for 22-46% in a maximum range loss scenario. In addition, we found some species to be more vulnerable to secondary than primary effects. Finally, we found high spatial variation in vulnerability: species on islands in Oceania are more vulnerable to primary SLR effects, whereas species on islands in Indo-Malaysia, with potentially 7-48 million SLR refugees, are more vulnerable to secondary effects. Our findings show that primary and secondary SLR effects can have enormous consequences for human inhabitants and island biodiversity, and that both need to be incorporated into ecological risk assessment, conservation, and regional planning. PMID:24501050

  19. Future climate change driven sea-level rise: secondary consequences from human displacement for island biodiversity.

    PubMed

    Wetzel, Florian T; Kissling, W Daniel; Beissmann, Helmut; Penn, Dustin J

    2012-09-01

    Sea-level rise (SLR) due to global warming will result in the loss of many coastal areas. The direct or primary effects due to inundation and erosion from SLR are currently being assessed; however, the indirect or secondary ecological effects, such as changes caused by the displacement of human populations, have not been previously evaluated. We examined the potential ecological consequences of future SLR on >1,200 islands in the Southeast Asian and the Pacific region. Using three SLR scenarios (1, 3, and 6 m elevation, where 1 m approximates most predictions by the end of this century), we assessed the consequences of primary and secondary SLR effects from human displacement on habitat availability and distributions of selected mammal species. We estimate that between 3-32% of the coastal zone of these islands could be lost from primary effects, and consequently 8-52 million people would become SLR refugees. Assuming that inundated urban and intensive agricultural areas will be relocated with an equal area of habitat loss in the hinterland, we project that secondary SLR effects can lead to an equal or even higher percent range loss than primary effects for at least 10-18% of the sample mammals in a moderate range loss scenario and for 22-46% in a maximum range loss scenario. In addition, we found some species to be more vulnerable to secondary than primary effects. Finally, we found high spatial variation in vulnerability: species on islands in Oceania are more vulnerable to primary SLR effects, whereas species on islands in Indo-Malaysia, with potentially 7-48 million SLR refugees, are more vulnerable to secondary effects. Our findings show that primary and secondary SLR effects can have enormous consequences for human inhabitants and island biodiversity, and that both need to be incorporated into ecological risk assessment, conservation, and regional planning.

  20. Climate changes, shifting ranges

    USGS Publications Warehouse

    Romanach, Stephanie

    2015-01-01

    Even a fleeting mention of the Everglades conjures colorful images of alligators, panthers, flamingos, and manatees. Over the centuries, this familiar cast of characters has become synonymous with life in south Florida. But the workings of a changing climate have the potential to significantly alter the menagerie of animals that call this area home. Global projections suggest south Florida wildlife will need to contend with higher temperatures, drier conditions, and rising seas in the years ahead. Recent modeling efforts shed new light on the potential outcomes these changes may have for threatened and endangered species in the area.

  1. Mitigating climate change via iron fertilization: Regional simulation of the Ross Sea, Antarctica

    NASA Astrophysics Data System (ADS)

    Arrigo, K. R.; Tagliabue, A.

    2003-04-01

    The dynamic 3-dimensional mesoscale model of the Coupled Ice, Atmosphere, and Ocean (CIAO) ecosystem in the southwestern Ross Sea has been used to investigate the interactions between environmental forcing and the production (primary and secondary) and fate of biogenic carbon. Early simulations by CIAO confirmed that in the Ross Sea, which contains the most productive waters in the Southern Ocean, phytoplankton consumed only about two-thirds of the available macronutrients due to the exhaustion of the available Fe. Simulating Fe-fertilization over the entire Ross Sea resulted in a 50% increase in peak phytoplankton abundance and a 30% increase in phosphate and nitrate utilization. This Fe-stimulated phytoplankton bloom reduced surface TCO2 by ~50 µmol kg-1 and pCO2 by as much as 80 µatm. Influx of atmospheric CO2 increased by 1-3 mmol C m-2 yr-1 as a result of the enhanced Fe supply, effectively doubling the rate of air-sea CO2 exchange in the Ross Sea. Because the Ross Sea supports distinct blooms of diatoms and the prymnesiophyte Phaeocystis antarctica, which differ in their nutrient and carbon utilization ratios, CIAO was used to assess the response of these two communities to exogenous Fe additions. It was found that when Fe was added, diatoms were driven to phosphate limitation and P. antarctica to nitrate limitation. Furthermore, the TCO2 content of surface waters dominated by P. antarctica was 15-26% lower than the TCO2 in waters dominated by diatoms, due primarily to the increased capacity of P. antarctica to draw down CO2.

  2. Climatic change by cloudiness linked to the spatial variability of sea surface temperatures

    NASA Technical Reports Server (NTRS)

    Otterman, J.

    1975-01-01

    An active role in modifying the earth's climate is suggested for low cloudiness over the circumarctic oceans. Such cloudiness, linked to the spatial differences in ocean surface temperatures, was studied. The temporal variations from year to year of ocean temperature patterns can be pronounced and therefore, the low cloudiness over this region should also show strong temporal variations, affecting the albedo of the earth and therefore the climate. Photographs are included.

  3. Ice Age Sea Level Change: Lessons From Studies of the Mid-Pliocene Climate Optimum, the Last Glacial Maximum and the 20th Century.

    NASA Astrophysics Data System (ADS)

    Mitrovica, J. X.; Raymo, M. E.; Morrow, E.; Hay, C.

    2011-12-01

    Renewed interest in geophysical models of ice age sea-level change has been motivated by three factors. First, the theory underlying these models has been progressively improved to take into account more complex viscoelastic Earth models and processes such as shoreline migration, changes in the extent of grounded marine-based ice sectors, and the impact on sea level of contemporaneous perturbations in the Earth's rotation. Second, results generated from these state-of-the-art models have highlighted the important information inherent to the geographic variability of sea-level change - information that is lost in analyses that are based on global (i.e., eustatic) averages. Third, there has been growing appreciation, through the application of the geophysical models, that accurate analyses of ancient sea level data sets can help to inform our understanding of future ice sheet stability in a warming world. In this talk we begin by summarizing a series of recent improvements in post-glacial sea-level theory and describe several applications that highlight important pitfalls in any effort to map sea-level measurements into estimates of past ice volumes. These applications include, in particular, studies of sea-level records from the mid-Pliocene climate optimum and the Last Glacial Maximum. We end by discussing an ongoing effort to use the geographic variability of rates obtained from tide gauge data and satellite altimetry records to estimate the dominant contributors to modern sea-level change.

  4. Mangroves facing climate change: landward migration potential in response to projected scenarios of sea level rise

    NASA Astrophysics Data System (ADS)

    Di Nitto, D.; Neukermans, G.; Koedam, N.; Defever, H.; Pattyn, F.; Kairo, J. G.; Dahdouh-Guebas, F.

    2013-02-01

    Mangrove forests prominently occupy an intertidal boundary position where the effects of sea level rise will be fast and well visible. This study in East Africa (Gazi Bay, Kenya) addresses the question whether mangroves can be resilient to a rise in sea level by focusing on their potential to migrate towards landwards areas. The combinatory analysis between remote sensing, DGPS-based ground truth and digital terrain models (DTM) unveils how real vegetation assemblages can shift under different projected (minimum (+9 cm), relative (+20 cm), average (+48 cm) and maximum (+88 cm)) scenarios of sea level rise (SLR). Under SLR scenarios up to 48 cm by the year 2100, the landward extension remarkably implies an area increase for each of the dominant mangrove assemblages, except for Avicennia marina and Ceriops tagal, both on the landward side. On one hand, the increase of most species in the first 3 scenarios, including the socio-economically most important species in this area, Rhizophora mucronata and C. tagal on the seaward side, strongly depends on the colonisation rate of these species. On the other hand, a SLR scenario of +88 cm by the year 2100 indicates that the area flooded only by equinoctial tides strongly decreases due to the topographical settings at the edge of the inhabited area. Consequently, the landward Avicennia-dominated assemblages will further decrease as a formation if they fail to adapt to a more frequent inundation. The topography is site-specific; however non-invadable areas can be typical for many mangrove settings.

  5. Changes in extreme sea levels in the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Dieterich, Christian; Gröger, Matthias; Andersson, Helén; Nerheim, Signild; Jönsson, Anette

    2016-04-01

    A newly developed shallow water model for the Baltic Sea and North Sea is presented. The model is validated by means of a comparison with hindcast simulations with observational data sets. The aim of the development is to provide and apply a modelling tool to model extreme sea levels in the Baltic Sea, Kattegat and Skagerrak. The model approach will support the direct analysis of extreme sea level observations in the past and provide the possibility to extend the statistical data base by producing very long time series or very large ensembles of coastal sea levels. This effort is intended to contribute to an assessment of risks due to storm surges and coastal flooding in the 21st century along the coast of Sweden. By using different RCP climate scenarios downscaled with a regional, coupled climate model atmospheric forcing is available to project possible changes in extreme sea levels into the future. Projected sea level rise, changes in dynamical sea level in the North East Atlantic and tidal forcing in the northern North Sea are applied as boundary condition which allows to investigate their impact on the dynamics of regional sea level variability. Initial experiments focus on the impact of model resolution, resolution in the atmospheric forcing and the amount of details necessary in the bathymetry to faithfully model coastal sea level in the Baltic Sea and North Sea.

  6. Effect of climate and environmental changes on plankton biodiversity and bigeochemical cycles of the Dongsha (Pratas) Atoll, South China Sea

    NASA Astrophysics Data System (ADS)

    Lo, Wen-tseng; Hsu, Pei-Kai; Hunag, Jia-Jang; Wang, Yu-Huai

    2013-04-01

    Dongsha (Pratas) Atoll, the so called "Pearl Crown of South China Sea", is a well-developed atoll with a total area of 80000 hectares. It possesses various ecosystems and has very high biodiversity, but it is very sensitive to climate change and physical processes. According to our investigation within the shallow semi-enclosed atoll in April, July, and October, 2011 (i.e., spring, summer, and autumn, respectively), we found that plankton assemblages and hydrographical conditions exhibited clear seasonal and spatial variations. Colder and higher salinity water was observed in April, while warmer water in July and lower salinity water in October, respectively. Nutrient concentration within the atoll was similar to that of the oligotrophic South China Sea waters and seemed to be in nitrogen-limit situation, while the distribution pattern of DOC and POC was mainly attributed to Chla and imported detritus matters. Carbon deposition flux also showed significant seasonal changes, but POC/PN value was near Redfield ratio, implying mostly due to biogenic factors; however it could still be classified as a typical coral ecosystem, since CaCO3 sinking flux generally was 30 times higher than that of organic matter. Plankton biodiversity was quite high in the atoll, and preformed apparent seasonal succession; in total, 82 phytoplankton species and 67 copepod species were recorded; furthermore, crab zoea (17.3% of the total zooplankton by number), fish eggs (12.5%), and shrimp larvae (4.2%), were relatively abundant in zooplankton community, revealed that atoll might be a good hatching ground. We deduced that the seasonal patterns of chemical and biological variables were mainly influenced by monsoons and precipitation, while small scales of temporal and spatial variations could be ascribed to internal wave and tide in this study area.

  7. I-C-SEA Change: A participatory tool for rapid assessment of vulnerability of tropical coastal communities to climate change impacts.

    PubMed

    Licuanan, Wilfredo Y; Samson, Maricar S; Mamauag, Samuel S; David, Laura T; Borja-Del Rosario, Roselle; Quibilan, Miledel Christine C; Siringan, Fernando P; Sta Maria, Ma Yvainne Y; España, Norievill B; Villanoy, Cesar L; Geronimo, Rollan C; Cabrera, Olivia C; Martinez, Renmar Jun S; Aliño, Porfirio M

    2015-12-01

    We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a "town-hall" meeting, facilitating further discussion, data validation, and even interactive scenario building.

  8. I-C-SEA Change: A participatory tool for rapid assessment of vulnerability of tropical coastal communities to climate change impacts.

    PubMed

    Licuanan, Wilfredo Y; Samson, Maricar S; Mamauag, Samuel S; David, Laura T; Borja-Del Rosario, Roselle; Quibilan, Miledel Christine C; Siringan, Fernando P; Sta Maria, Ma Yvainne Y; España, Norievill B; Villanoy, Cesar L; Geronimo, Rollan C; Cabrera, Olivia C; Martinez, Renmar Jun S; Aliño, Porfirio M

    2015-12-01

    We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a "town-hall" meeting, facilitating further discussion, data validation, and even interactive scenario building. PMID:26036847

  9. Challenges of climate change

    PubMed Central

    Husaini, Amjad M

    2014-01-01

    Kashmir valley is a major saffron (Crocus sativus Kashmirianus) growing area of the world, second only to Iran in terms of production. In Kashmir, saffron is grown on uplands (termed in the local language as “Karewas”), which are lacustrine deposits located at an altitude of 1585 to 1677 m above mean sea level (amsl), under temperate climatic conditions. Kashmir, despite being one of the oldest historical saffron-producing areas faces a rapid decline of saffron industry. Among many other factors responsible for decline of saffron industry the preponderance of erratic rainfalls and drought-like situation have become major challenges imposed by climate change. Saffron has a limited coverage area as it is grown as a ‘niche crop’ and is a recognized “geographical indication,” growing under a narrow microclimatic condition. As such it has become a victim of climate change effects, which has the potential of jeopardizing the livelihood of thousands of farmers and traders associated with it. The paper discusses the potential and actual impact of climate change process on saffron cultivation in Kashmir; and the biotechnological measures to address these issues. PMID:25072266

  10. Mangroves facing climate change: landward migration potential in response to projected scenarios of sea level rise

    NASA Astrophysics Data System (ADS)

    Di Nitto, D.; Neukermans, G.; Koedam, N.; Defever, H.; Pattyn, F.; Kairo, J. G.; Dahdouh-Guebas, F.

    2014-02-01

    Mangrove forests prominently occupy an intertidal boundary position where the effects of sea level rise will be fast and well visible. This study in East Africa (Gazi Bay, Kenya) addresses the question of whether mangroves can be resilient to a rise in sea level by focusing on their potential to migrate towards landward areas. The combinatory analysis between remote sensing, DGPS-based ground truth and digital terrain models (DTM) unveils how real vegetation assemblages can shift under different projected (minimum (+9 cm), relative (+20 cm), average (+48 cm) and maximum (+88 cm)) scenarios of sea level rise (SLR). Under SLR scenarios up to 48 cm by the year 2100, the landward extension remarkably implies an area increase for each of the dominant mangrove assemblages except for Avicennia marina and Ceriops tagal, both on the landward side. On the one hand, the increase in most species in the first three scenarios, including the socio-economically most important species in this area, Rhizophora mucronata and C. tagal on the seaward side, strongly depends on the colonisation rate of these species. On the other hand, a SLR scenario of +88 cm by the year 2100 indicates that the area flooded only by equinoctial tides strongly decreases due to the topographical settings at the edge of the inhabited area. Consequently, the landward Avicennia-dominated assemblages will further decrease as a formation if they fail to adapt to a more frequent inundation. The topography is site-specific; however non-invadable areas can be typical for many mangrove settings.

  11. Changing climate and sea level alter Hg mobility at Lake Tulane, Florida, U.S.

    PubMed

    Jacobson, G L; Norton, S A; Grimm, E C; Edgar, T

    2012-11-01

    Between 45,000 cal years BP and the beginning of the Holocene, the accumulation rate for Hg in sediments of Lake Tulane, Florida ranged from ≈2 to 10 μg m(-2) yr(-1), compared with 53 μg Hg m(-2) yr(-1) in the 1985-1990 period of anthropogenic input. The locality experienced regional draw-down of the water table during the Wisconsinan glaciation, which lowered global sea level by nearly 130 m. Natural atmospheric deposition of Hg to the surrounding area resulted in long-term (ca. 100,000 years) sequestration of this atmospheric flux of Hg, primarily by adsorption in the oxic Al- and Fe-hydroxide-rich sandy subsoil. Global sea level rise during deglaciation led to a rising regional water table, flooding the oxidized soils surrounding Tulane. Iron and adsorbed Hg were mobilized by reductive dissolution and transported by groundwater flow to Lake Tulane and ultimately to the accumulating sediment. The accumulation rate of Hg (and Fe) increased rapidly about 16,000 cal years BP, peaked at nearly 60 μg Hg m(-2) yr(-1) ca. 13,000-14,000 cal years BP, declined sharply during the Younger Dryas, and then increased sharply to a second 60 μg Hg m(-2) yr(-1) peak about 5000 cal years BP. Thereafter, it declined nearly to background by 900 cal years BP. In similar geologic situations, rapid modern sea level rise will initiate this process globally, and may mobilize large accumulations of Hg and lesser amounts of As, and other redox sensitive metals to groundwater and surface water.

  12. Breeding periodicity for male sea turtles, operational sex ratios, and implications in the face of climate change.

    PubMed

    Hays, Graeme C; Fossette, Sabrina; Katselidis, Kostas A; Schofield, Gail; Gravenor, Mike B

    2010-12-01

    Species that have temperature-dependent sex determination (TSD) often produce highly skewed offspring sex ratios contrary to long-standing theoretical predictions. This ecological enigma has provoked concern that climate change may induce the production of single-sex generations and hence lead to population extirpation. All species of sea turtles exhibit TSD, many are already endangered, and most already produce sex ratios skewed to the sex produced at warmer temperatures (females). We tracked male loggerhead turtles (Caretta caretta) from Zakynthos, Greece, throughout the entire interval between successive breeding seasons and identified individuals on their breeding grounds, using photoidentification, to determine breeding periodicity and operational sex ratios. Males returned to breed at least twice as frequently as females. We estimated that the hatchling sex ratio of 70:30 female to male for this rookery will translate into an overall operational sex ratio (OSR) (i.e., ratio of total number of males vs females breeding each year) of close to 50:50 female to male. We followed three male turtles for between 10 and 12 months during which time they all traveled back to the breeding grounds. Flipper tagging revealed the proportion of females returning to nest after intervals of 1, 2, 3, and 4 years were 0.21, 0.38, 0.29, and 0.12, respectively (mean interval 2.3 years). A further nine male turtles were tracked for short periods to determine their departure date from the breeding grounds. These departure dates were combined with a photoidentification data set of 165 individuals identified on in-water transect surveys at the start of the breeding season to develop a statistical model of the population dynamics. This model produced a maximum likelihood estimate that males visit the breeding site 2.6 times more often than females (95%CI 2.1, 3.1), which was consistent with the data from satellite tracking and flipper tagging. Increased frequency of male breeding will

  13. Climate Change Schools Project...

    ERIC Educational Resources Information Center

    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…

  14. Depositional History of a Saline Blue Hole on Eleuthera Island, Bahamas: Implications for Sea Level History and Climate Change

    NASA Astrophysics Data System (ADS)

    Brady, K.; Bernard, M.; Bender, S.; Roy, Z.; Boush, L. E.; Myrbo, A.; Brown, E. T.; Buynevich, I. V.; Berman, M.; Gnivecki, P.

    2013-12-01

    Physical, chemical and biological properties of Duck Pond Blue Hole (DPBH), located on the southern portion of Eleuthera Island, Bahamas, were examined to analyze its depositional history and the record of climate and anthropogenic changes on the island. DPBH is a small (.001 km2), circular inland blue hole with average salinity ranging from 20-28 ppt and a maximum depth of ~8 m. Sediment cores were recovered using standard piston coring techniques along a transect consisting of three sites yielding cores of varying lengths--170, 155 and 151 cm, respectively. Radiocarbon dating, x-ray fluorescence (XRF), grain size analysis, loss on ignition (LOI), smear slide and mollusk processing and identification were performed on the cores. The sediment recovered is dominated by brown, tan and white carbonate sand with varying amounts of organic matter. Sedimentation rates vary between 0.1-0.5 mm/year. Mollusks are found throughout the cores but gastropods dominate in the upper portions, which date from 2000 years BP to present day. Bivalves are abundant in intervals dating between 5000 and 2500 years BP. The most common bivalve species were Polymesoda maritima, Anomalocardis auberiana and Ervilia concentrica. The most common gastropods were Cerithidea costata and Cerithium lutosum. Drill holes made by predaceous gastropods occur on some of the gastropods, but on most of the bivalves. Drilling frequency is highest between 5000 and 2500 years BP even though gastropods are rarely preserved in that interval. Through smear slide analysis, diatoms, forams and ostracodes were also found to occur throughout the core record. Peaks in Fe and Sr from XRF scans at 0.5 cm intervals may represent records of high atmospheric dust concentrations and sea level fluctuations, respectively. Plotting mollusk bed depths versus calibrated age reveals a sea level rise over the last 6000 years that includes a rapid rise and subsequent fall at ~2500 year BP.

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

    SciTech Connect

    1985-09-01

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

  16. Extreme sea-levels, coastal risks and climate changes: lost in translation

    NASA Astrophysics Data System (ADS)

    Marone, Eduardo; Castro Carneiro, Juliane; Cintra, Márcio; Ribeiro, Andréa; Cardoso, Denis; Stellfeld, Carol

    2014-05-01

    Occurring commonly in Brazilian coastal (and continental) areas, floods are probably the most devastating natural hazards our local society faces nowadays. With the expected sea-level rise and tropical storms becoming stronger and more frequents, the scenarios of local impacts of sea-level rise and storm surges; causing loss of lives, environmental damages and socio-economic stress; need to be addressed and properly communicated. We present results related to the sea-level setups accordingly to IPCC's scenarios and the expected coastal floods in the Paraná State, Southern Brazil. The outcomes are displayed in scientific language accompanied by "translations" with the objective of showing the need of a different language approach to communicate with the players affected by coastal hazards. To create the "translation" of the "scientific" text we used the Up-Goer Five Text Editor, which allows writing texts using only the ten hundred most used English words. We allowed ourselves to use a maximum of five other words per box not present at this dictionary, not considering geographical names or units in the count, provided there were simple. That was necessary because words as sea, beach, sand, storm, etc., are not among the one thousand present at the Up-Goer, and they are simple enough anyhow. On the other hand, the not scientific public we targeted speaks Portuguese, not English, and we do not have an Up-Goer tool for that language. Anyhow, each Box was also produced in Portuguese, as much simple as possible, to disseminate our results to the local community. To illustrate the need of "translation", it is worthy to mention a real case of a troublesome misunderstanding caused by us, scientists, in our coastal society. Some years ago, one of our colleagues at the university, a much-respected scientist, informed through a press release that, on a given day, "we will experience the highest astronomical tide of the century". That statement (scientifically true and

  17. Climate change and dead zones.

    PubMed

    Altieri, Andrew H; Gedan, Keryn B

    2015-04-01

    Estuaries and coastal seas provide valuable ecosystem services but are particularly vulnerable to the co-occurring threats of climate change and oxygen-depleted dead zones. We analyzed the severity of climate change predicted for existing dead zones, and found that 94% of dead zones are in regions that will experience at least a 2 °C temperature increase by the end of the century. We then reviewed how climate change will exacerbate hypoxic conditions through oceanographic, ecological, and physiological processes. We found evidence that suggests numerous climate variables including temperature, ocean acidification, sea-level rise, precipitation, wind, and storm patterns will affect dead zones, and that each of those factors has the potential to act through multiple pathways on both oxygen availability and ecological responses to hypoxia. Given the variety and strength of the mechanisms by which climate change exacerbates hypoxia, and the rates at which climate is changing, we posit that climate change variables are contributing to the dead zone epidemic by acting synergistically with one another and with recognized anthropogenic triggers of hypoxia including eutrophication. This suggests that a multidisciplinary, integrated approach that considers the full range of climate variables is needed to track and potentially reverse the spread of dead zones.

  18. Climate change and dead zones.

    PubMed

    Altieri, Andrew H; Gedan, Keryn B

    2015-04-01

    Estuaries and coastal seas provide valuable ecosystem services but are particularly vulnerable to the co-occurring threats of climate change and oxygen-depleted dead zones. We analyzed the severity of climate change predicted for existing dead zones, and found that 94% of dead zones are in regions that will experience at least a 2 °C temperature increase by the end of the century. We then reviewed how climate change will exacerbate hypoxic conditions through oceanographic, ecological, and physiological processes. We found evidence that suggests numerous climate variables including temperature, ocean acidification, sea-level rise, precipitation, wind, and storm patterns will affect dead zones, and that each of those factors has the potential to act through multiple pathways on both oxygen availability and ecological responses to hypoxia. Given the variety and strength of the mechanisms by which climate change exacerbates hypoxia, and the rates at which climate is changing, we posit that climate change variables are contributing to the dead zone epidemic by acting synergistically with one another and with recognized anthropogenic triggers of hypoxia including eutrophication. This suggests that a multidisciplinary, integrated approach that considers the full range of climate variables is needed to track and potentially reverse the spread of dead zones. PMID:25385668

  19. Gulf of Mexico Climate, Laurentide Ice Sheet History, and Global Sea Level Change During the Last Glacial Cycle

    NASA Astrophysics Data System (ADS)

    Flower, B. P.; Williams, C.; Brown, E. A.; Hastings, D. W.; Hill, H.; Adams, S.; Hendrix, J.; Martin, E. E.; Biller, N. B.; Goddard, E.

    2011-12-01

    The interactions between low-latitude Atlantic climate and high-latitude ice sheet variability represent an important issue in past abrupt climate change. Specifically, Laurentide Ice Sheet (LIS) meltwater input seems to be decoupled at the millennial scale from Gulf of Mexico sea-surface temperature (SST), as well as Greenland air temperature, during the last glacial cycle. Indeed, comparison to Greenland ice core records indicate significant meltwater input during some North Atlantic cool episodes, including Heinrich Stadials 4, 3, and 1. Here we present published and new Mg/Ca and δ18O data on the planktic foraminifer Globigerinoides ruber from northern Gulf of Mexico sediment cores that provide detailed records of SST, δ18O of seawater (δ18Osw), and inferred salinity for the 48-10 ka interval. Age control for Orca Basin cores MD02-2550 and -2551 is based on AMS 14C dates on G. ruber and documents continuous sedimentation at rates >35 cm/kyr. Significant meltwater input is inferred from δ18Osw data during Antarctic Isotope Maxima (AIM) events and reaches a peak during the Bølling/Allerød, consistent with bipolar warming and a high sensitivity to greenhouse forcing. Furthermore, bulk sediment δ18O data show a brief spike reaching -5.5% ca. 14.5 ka during an interval barren of foraminifera. We speculate that this excursion represents fine carbonate sediment from Canadian Paleozoic marine carbonates, analogous to detrital carbonate in the North Atlantic that has a δ18O value of -5%. Radiogenic isotope data (Nd and Pb) also reach peak values at this interval, indicative of older continental material sourced from Canada vs. younger material from the Mississippi River drainage basin. Inferred major meltwater flow appears to have been associated with meltwater pulse 1a within the Bølling warm interval, consistent with a significant contribution by the LIS to rapid global sea level rise. Overall, the relations between Gulf of Mexico meltwater input, Heinrich

  20. Sensitivity of the North Atlantic Ocean Circulation to an abrupt change in the Nordic Sea overflow in a high resolution global coupled climate model

    NASA Astrophysics Data System (ADS)

    Zhang, Rong; Delworth, Thomas L.; Rosati, Anthony; Anderson, Whit G.; Dixon, Keith W.; Lee, Hyun-Chul; Zeng, Fanrong

    2011-12-01

    The sensitivity of the North Atlantic Ocean Circulation to an abrupt change in the Nordic Sea overflow is investigated for the first time using a high resolution eddy-permitting global coupled ocean-atmosphere model (GFDL CM2.5). The Nordic Sea overflow is perturbed through the change of the bathymetry in GFDL CM2.5. We analyze the Atlantic Meridional Overturning Circulation (AMOC) adjustment process and the downstream oceanic response to the perturbation. The results suggest that north of 34°N, AMOC changes induced by changes in the Nordic Sea overflow propagate on the slow tracer advection timescale, instead of the fast Kelvin wave timescale, resulting in a time lead of several years between subpolar and subtropical AMOC changes. The results also show that a stronger and deeper-penetrating Nordic Sea overflow leads to stronger and deeper AMOC, stronger northward ocean heat transport, reduced Labrador Sea deep convection, stronger cyclonic Northern Recirculation Gyre (NRG), westward shift of the North Atlantic Current (NAC) and southward shift of the Gulf Stream, warmer sea surface temperature (SST) east of Newfoundland and colder SST south of the Grand Banks, stronger and deeper NAC and Gulf Stream, and stronger oceanic eddy activities along the NAC and the Gulf Stream paths. A stronger/weaker Nordic Sea overflow also leads to a contracted/expanded subpolar gyre (SPG). This sensitivity study points to the important role of the Nordic Sea overflow in the large scale North Atlantic ocean circulation, and it is crucial for climate models to have a correct representation of the Nordic Sea overflow.

  1. Causes for contemporary regional sea level changes.

    PubMed

    Stammer, Detlef; Cazenave, Anny; Ponte, Rui M; Tamisiea, Mark E

    2013-01-01

    Regional sea level changes can deviate substantially from those of the global mean, can vary on a broad range of timescales, and in some regions can even lead to a reversal of long-term global mean sea level trends. The underlying causes are associated with dynamic variations in the ocean circulation as part of climate modes of variability and with an isostatic adjustment of Earth's crust to past and ongoing changes in polar ice masses and continental water storage. Relative to the coastline, sea level is also affected by processes such as earthquakes and anthropogenically induced subsidence. Present-day regional sea level changes appear to be caused primarily by natural climate variability. However, the imprint of anthropogenic effects on regional sea level-whether due to changes in the atmospheric forcing or to mass variations in the system-will grow with time as climate change progresses, and toward the end of the twenty-first century, regional sea level patterns will be a superposition of climate variability modes and natural and anthropogenically induced static sea level patterns. Attribution and predictions of ongoing and future sea level changes require an expanded and sustained climate observing system.

  2. CLIMLINK: Climate forcing factors for marine environmental change during the mid- and late Holocene - a link between the NE Atlantic and the Baltic Sea.

    NASA Astrophysics Data System (ADS)

    Polovodova Asteman, Irina; Risebrobakken, Bjørg; Bąk, Małgorzata; Binczewska, Anna; Borówka, Ryszard; Dobosz, Sławomir; Jansen, Eystein; Kaniak, Aleksandra; Moros, Matthias; Perner, Kerstin; Sławinska, Joanna

    2015-04-01

    Climate change has a strong amplifying effect on the environment of marginal seas such as the Baltic Sea. Owing to the connection of the Baltic Sea with the Atlantic (and the resultant pathway of water exchange via the narrow Danish Straits), changes in the Baltic region are suggested to be driven by external oceanic and atmospheric forcing originating in the Atlantic, particularly in the eastern Nordic seas, the Skagerrak, and the Kattegat. CLIMLINK aims to reconstruct mid- to late Holocene ecosystem changes in these regions and identify linkages, common forcing factors and effects for the Baltic Sea on a millennial to decadal time scale. High-resolution sediment records from selected key sites in the Norwegian Trench, and central Baltic Sea are studied by using a multi-proxy approach. Micropalaeontological studies of diatoms and foraminifera are combined with geochemical proxies, such as stable isotopes, Mg/Ca, TOC, TIC, C/N, XRF and magnetic susceptibility in order to achieve a more comprehensive view on environmental changes during the last 6000 to 8000 years. The chronology of the sediment cores is secured by using multiple dating tools: Hg-pollution records, 137Cs, 210Pb, 14C and tephra layers. Herein we present the initial results of the project.

  3. Preparing for climate change.

    PubMed

    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

  4. Understanding recent climate change.

    PubMed

    Serreze, Mark C

    2010-02-01

    The Earth's atmosphere has a natural greenhouse effect, without which the global mean surface temperature would be about 33 degrees C lower and life would not be possible. Human activities have increased atmospheric concentrations of carbon dioxide, methane, and other gases in trace amounts. This has enhanced the greenhouse effect, resulting in surface warming. Were it not for the partly offsetting effects of increased aerosol concentrations, the increase in global mean surface temperature over the past 100 years would be larger than observed. Continued surface warming through the 21st century is inevitable and will likely have widespread ecological impacts. The magnitude and rate of warming for the global average will be largely dictated by the strength and direction of climate feedbacks, thermal inertia of the oceans, the rate of greenhouse gas emissions, and aerosol concentrations. Because of regional expressions of climate feedbacks, changes in atmospheric circulation, and a suite of other factors, the magnitude and rate of warming and changes in other key climate elements, such as precipitation, will not be uniform across the planet. For example, due to loss of its floating sea-ice cover, the Arctic will warm the most.

  5. Climate change and the collapse of the Akkadian empire: Evidence from the deep sea

    SciTech Connect

    Cullen, H.M.; Menocal, P.B. de; Hemming, S.; Hemming, G.; Brown, F.H.; Guilderson, T.; Sirocko, F.

    2000-04-01

    The Akkadian empire ruled Mesopotamia from the headwaters of the Tigris-Euphrates Rivers to the Persian Gulf during the late third millennium B.C. Archeological evidence has shown that this highly developed civilization collapsed abruptly near 4,170 {+-} 150 calendar yr B.P., perhaps related to a shift to more arid conditions. Detailed paleoclimate records to test this assertion from Mesopotamia are rare, but changes in regional aridity are preserved in adjacent ocean basins. The authors document Holocene changes in regional aridity using mineralogic and geochemical analyses of a marine sediment core from the Gulf of Oman, which is directly downwind of Mesopotamian dust source areas and archeological sites. Results document a very abrupt increase in eolian dust and Mesopotamian aridity, accelerator mass spectrometer radiocarbon dates to 4,025 {+-} 125 calendar yr B.P., which persisted for {approximately} 300 yr. Radiogenic (Nd and Sr) isotope analyses confirm that the observed increase in mineral dust was derived from Mesopotamian source areas. Geochemical correlation of volcanic ash shards between the archeological site and marine sediment record establishes a direct temporal link between Mesopotamian aridification and social collapse, implicating a sudden shift to more arid conditions as a key factor contributing to the collapse of the Akkadian empire.

  6. Climate change and the collapse of the Akkadian empire: Evidence from the deep sea

    NASA Astrophysics Data System (ADS)

    Cullen, H. M.; Demenocal, P. B.; Hemming, S.; Hemming, G.; Brown, F. H.; Guilderson, T.; Sirocko, F.

    2000-04-01

    The Akkadian empire ruled Mesopotamia from the headwaters of the Tigris-Euphrates Rivers to the Persian Gulf during the late third millennium B.C. Archeological evidence has shown that this highly developed civilization collapsed abruptly near 4170 ± 150 calendar yr B.P., perhaps related to a shift to more arid conditions. Detailed paleoclimate records to test this assertion from Mesopotamia are rare, but changes in regional aridity are preserved in adjacent ocean basins. We document Holocene changes in regional aridity using mineralogic and geochemical analyses of a marine sediment core from the Gulf of Oman, which is directly downwind of Mesopotamian dust source areas and archeological sites. Our results document a very abrupt increase in eolian dust and Mesopotamian aridity, accelerator mass spectrometer radiocarbon dated to 4025 ± 125 calendar yr B.P., which persisted for ˜300 yr. Radiogenic (Nd and Sr) isotope analyses confirm that the observed increase in mineral dust was derived from Mesopotamian source areas. Geochemical correlation of volcanic ash shards between the archeological site and marine sediment record establishes a direct temporal link between Mesopotamian aridification and social collapse, implicating a sudden shift to more arid conditions as a key factor contributing to the collapse of the Akkadian empire.

  7. Mangrove expansion in the Gulf of Mexico with climate change: Implications for wetland health and resistance to rising sea levels

    NASA Astrophysics Data System (ADS)

    Comeaux, Rebecca S.; Allison, Mead A.; Bianchi, Thomas S.

    2012-01-01

    Black mangroves ( Avicennia spp.) are hypothesized to expand their latitudinal range with global climate change in the 21st century, induced by a reduction in the frequency and severity of coastal freezes, which are known to limit mangrove colony extent and individual tree size. The Gulf of Mexico is a prime candidate for population expansion to occur because it is located at the northward limit of black mangrove habitat. This may come at the expense of existing coastal saline wetlands that are dominantly Spartina spp. marsh grasses. The present study was conducted to focus on the implications of a marsh to mangrove transition in Gulf wetlands, specifically: (1) wetland resistance to accelerating eustatic sea level rise (ESLR) rates; (2) resistance to wave attack in large storms (increased cyclonic storm frequency/intensity is predicted with future climate warming); and (3) organic carbon sequestration and wetland soil geochemistry. Field sites of adjacent and inter-grown Avicennia germinans mangrove and Spartina marsh populations in similar geomorphological setting were selected in back-barrier areas near Port Aransas and Galveston, TX. Elevation surveys in the more mature Port Aransas site indicate mangrove vegetated areas are 4 cm higher in elevation than surrounding marsh on an average regional scale, and 1-2 cm higher at the individual mangrove scale. 210Pb and 137Cs accumulation rates and loss on ignition data indicate that mineral trapping is 4.1 times higher and sediment organics are 1.7 times lower in mangroves at Port Aransas. This additional mineral trapping does not differ in grain size character from marsh accumulation. Elevation change may also be effected by soil displacement of higher root volumes in mangrove cores. Port Aransas porosities are lower in mangrove rooted horizons, with a corresponding increase in sediment strength, suggesting mangrove intervals are more resistant to wave-induced erosion during storm events. Port Aransas mangroves

  8. Climate Change and National Security

    SciTech Connect

    Malone, Elizabeth L.

    2013-02-01

    Climate change is increasingly recognized as having national security implications, which has prompted dialogue between the climate change and national security communities – with resultant advantages and differences. Climate change research has proven useful to the national security community sponsors in several ways. It has opened security discussions to consider climate as well as political factors in studies of the future. It has encouraged factoring in the stresses placed on societies by climate changes (of any kind) to help assess the potential for state stability. And it has shown that, changes such as increased heat, more intense storms, longer periods without rain, and earlier spring onset call for building climate resilience as part of building stability. For the climate change research community, studies from a national security point of view have revealed research lacunae, for example, such as the lack of usable migration studies. This has also pushed the research community to consider second- and third-order impacts of climate change, such as migration and state stability, which broadens discussion of future impacts beyond temperature increases, severe storms, and sea level rise; and affirms the importance of governance in responding to these changes. The increasing emphasis in climate change science toward research in vulnerability, resilience, and adaptation also frames what the intelligence and defense communities need to know, including where there are dependencies and weaknesses that may allow climate change impacts to result in security threats and where social and economic interventions can prevent climate change impacts and other stressors from resulting in social and political instability or collapse.

  9. Fiddling with climate change

    NASA Astrophysics Data System (ADS)

    2012-01-01

    Composer and string musician, turned award-winning environmentalist, Aubrey Meyer tells Nature Climate Change why he is campaigning for countries to adopt his 'contraction and convergence' model of global development to avoid dangerous climate change.

  10. Climate Change and Health

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 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. Adaptation Planning to Minimize Damage to Road Infrastructure from Rising Groundwater Associated with Climate Change and Sea Level Rise in Coastal New Hampshire

    NASA Astrophysics Data System (ADS)

    Knott, J. F.; Jacobs, J. M.; Daniel, J.; Kirshen, P. H.

    2015-12-01

    Coastal communities with high population density and infrastructure close to the shoreline are vulnerable to the effects of climate change and sea level rise (SLR). In the northeast, annual precipitation has increased by more than 10-percent in the last 100 years and is projected to increase further in the future. In addition, sea level in coastal New Hampshire is projected to rise 1.2 to 2.0 meters by the year 2100 (New Hampshire Coastal Risks and Hazards Commission). Climate change vulnerability and adaptation studies have primarily focused on surface water flooding from SLR; however, little attention has been given to rising waters from beneath the ground surface. Groundwater in many coastal communities will rise with rising sea level which will likely have important consequences for water quality, the structural integrity of foundations and infrastructure, and the health of natural ecosystems in the coastal zone. In this study, we have constructed a regional groundwater flow model of coastal New Hampshire to investigate the effect of various climate change and SLR scenarios on groundwater levels, focusing on impacts to road infrastructure. Using LiDAR datasets and downscaled global climate predictions, we determined that the interaction of several hydrogeological factors resulted in distinct spatial patterns of groundwater rise that were not evident from simple models linking SLR and terrain. Furthermore, by loosely coupling the groundwater model to a hydraulic model for pavement systems, we were able to identify sections of roadways that will have compromised pavement performance due to rising groundwater intersecting the sublayers of these roadways. Our findings broadly suggest that adaptation strategies designed to counter the effects of climate change and SLR in coastal communities must consider potential damage from rising groundwater in addition to surface water impacts not only immediately along the coast but also at significant distances inland.

  12. Geomorphic responses to climatic change

    SciTech Connect

    Bull, W.B.

    1991-01-01

    The primary focus of this book is the response of landscapes to Pleistocene and Holocene climatic changes. During the past 40 ky the global climate has varied from full-glacial to interglacial. Global temperatures decreased between 40 and 20 ka culminating in full-glacial climatic conditions at 20 ka. This resulted in a sea level decline of 130 m. Only 8 to 14 ky later the global temperature had reversed itself and the climate was the warmest of the past 120 ky. These dramatic changes in climate imposed significant controls on fluvial systems and impacted land forms and whole landscapes worldwide. Chapter 1, Conceptual Models for Changing landscapes, presents numerous concepts related to erosional and depositional processes controlling landscape development. Each of the next four chapters of the book, 2, 3, 4, and 5, examine different aspects of climatic change on fluvial systems. The conceptual models are used to analyze landscape response in four different climatic and geologic settings. In each setting the present and past climatic conditions, the climatically induced changes in vegetation and soil development, and geochronology are considered in assessing the influence of climatic changes on geomorphic processes. Chapter 2, investigates the influence of climatic change on the geomorphic processes operating in desert watersheds in the southwestern US and northern Mexico. The study sites for Chapter 3, are small desert drainage basins in the southwestern US and near the Sinai Peninsula in the Middle East. Chapter 4, investigates fill terraces in several drainage basins of the San Gabrial Mountains of the central Transverse Ranges of coastal southern California. The study site for Chapter 5 is the Charwell River watershed in the Seaward Kaikoura Range of New Zealand. Chapter 6, Difference Responses of Arid and Humid Fluvial Systems, compares the effects of changing climates in basins that range from extremely arid to humid.

  13. Impacts of climate-change-driven sea level rise on intertidal rocky reef habitats will be variable and site specific.

    PubMed

    Thorner, Jaqueline; Kumar, Lalit; Smith, Stephen D A

    2014-01-01

    Intertidal rocky reefs are complex and rich ecosystems that are vulnerable to even the smallest fluctuations in sea level. We modelled habitat loss associated with sea level rise for intertidal rocky reefs using GIS, high-resolution digital imagery, and LIDAR technology at fine-scale resolution (0.1 m per pixel). We used projected sea levels of +0.3 m, +0.5 m and +1.0 m above current Mean Low Tide Level (0.4 m). Habitat loss and changes were analysed for each scenario for five headlands in the Solitary Islands Marine Park (SIMP), Australia. The results indicate that changes to habitat extent will be variable across different shores and will not necessarily result in net loss of area for some habitats. In addition, habitat modification will not follow a regular pattern over the projected sea levels. Two of the headlands included in the study currently have the maximum level of protection within the SIMP. However, these headlands are likely to lose much of the habitat known to support biodiverse assemblages and may not continue to be suitable sanctuaries into the future. The fine-scale approach taken in this study thus provides a protocol not only for modelling habitat modification but also for future proofing conservation measures under a scenario of changing sea levels. PMID:24465915

  14. Impacts of Climate-Change-Driven Sea Level Rise on Intertidal Rocky Reef Habitats Will Be Variable and Site Specific

    PubMed Central

    Thorner, Jaqueline; Kumar, Lalit; Smith, Stephen D. A.

    2014-01-01

    Intertidal rocky reefs are complex and rich ecosystems that are vulnerable to even the smallest fluctuations in sea level. We modelled habitat loss associated with sea level rise for intertidal rocky reefs using GIS, high-resolution digital imagery, and LIDAR technology at fine-scale resolution (0.1 m per pixel). We used projected sea levels of +0.3 m, +0.5 m and +1.0 m above current Mean Low Tide Level (0.4 m). Habitat loss and changes were analysed for each scenario for five headlands in the Solitary Islands Marine Park (SIMP), Australia. The results indicate that changes to habitat extent will be variable across different shores and will not necessarily result in net loss of area for some habitats. In addition, habitat modification will not follow a regular pattern over the projected sea levels. Two of the headlands included in the study currently have the maximum level of protection within the SIMP. However, these headlands are likely to lose much of the habitat known to support biodiverse assemblages and may not continue to be suitable sanctuaries into the future. The fine-scale approach taken in this study thus provides a protocol not only for modelling habitat modification but also for future proofing conservation measures under a scenario of changing sea levels. PMID:24465915

  15. Impacts of climate-change-driven sea level rise on intertidal rocky reef habitats will be variable and site specific.

    PubMed

    Thorner, Jaqueline; Kumar, Lalit; Smith, Stephen D A

    2014-01-01

    Intertidal rocky reefs are complex and rich ecosystems that are vulnerable to even the smallest fluctuations in sea level. We modelled habitat loss associated with sea level rise for intertidal rocky reefs using GIS, high-resolution digital imagery, and LIDAR technology at fine-scale resolution (0.1 m per pixel). We used projected sea levels of +0.3 m, +0.5 m and +1.0 m above current Mean Low Tide Level (0.4 m). Habitat loss and changes were analysed for each scenario for five headlands in the Solitary Islands Marine Park (SIMP), Australia. The results indicate that changes to habitat extent will be variable across different shores and will not necessarily result in net loss of area for some habitats. In addition, habitat modification will not follow a regular pattern over the projected sea levels. Two of the headlands included in the study currently have the maximum level of protection within the SIMP. However, these headlands are likely to lose much of the habitat known to support biodiverse assemblages and may not continue to be suitable sanctuaries into the future. The fine-scale approach taken in this study thus provides a protocol not only for modelling habitat modification but also for future proofing conservation measures under a scenario of changing sea levels.

  16. Climate change effects on environment (marine, atmospheric and terrestrial) and human perception in an Italian Region (Marche) and the nearby northern Adriatic Sea.

    NASA Astrophysics Data System (ADS)

    Appiotti, F.; Krzelj, M.; Marincioni, F.; Russo, A.

    2012-04-01

    An integrated analysis of recent climate change, including atmosphere, sea and land, as well as some of the impacts on society, has been conducted on the Marche Region in central Italy and the northern portion of the Adriatic Sea. The Marche Region is one of the 20 administrative divisions of Italy, located at a latitude approximately 43° North, with a total surface area of 9,366 km2 and 1,565,000 residents. The northern Adriatic Sea is the northernmost area of the Mediterranean Sea, and it has peculiar relevance for several aspects (environment, tourism, fisheries, economy). The collected environmental data included meteorological stations (daily maximum and minimum air temperature, daily precipitation), oceanographic stations (sea temperature, salinity, dissolved oxygen, nutrient salts concentration, chlorophyll) and river flows, over the last 50 years. The collected social data include 800 questionnaires and interviews carried out on selected samples of residents, decision-makers and emergency managers. These questionnaires and interviews aimed at highlighting the perception of climate change risks. The trend analysis of air temperature and precipitation data detailed an overall temperature increase in all seasons and rainfall decreases in Winter, Spring and Summer with Autumn increases, influencing river flow changes. Marine data showed a relevant warming of the water column in the period after 1990 in comparison with the previous period, particularly in the cold season. Surface salinity increased in Spring and Summer and strongly decreased in Autumn and Winter (according with the precipitation and river flow changes). These last mentioned changes, combined with anthropogenic effects, also influenced the marine ecosystems, with changes of nutrient salts, chlorophyll and dissolved oxygen. Changes in nutrient discharge from rivers influenced the average marine chlorophyll concentration reduction and the consequent average reduction of warm season hypoxic

  17. The Changing Climate.

    ERIC Educational Resources Information Center

    Schneider, Stephen H.

    1989-01-01

    Discusses the global change of climate. Presents the trend of climate change with graphs. Describes mathematical climate models including expressions for the interacting components of the ocean-atmosphere system and equations representing the basic physical laws governing their behavior. Provides three possible responses on the change. (YP)

  18. A vertically integrated snow/ice model over land/sea for climate models. I - Development. II - Impact on orbital change experiments

    NASA Technical Reports Server (NTRS)

    Neeman, Binyamin U.; Ohring, George; Joseph, Joachim H.

    1988-01-01

    A vertically integrated formulation (VIF) model for sea ice/snow and land snow is discussed which can simulate the nonlinear effects of heat storage and transfer through the layers of snow and ice. The VIF demonstates the accuracy of the multilayer formulation, while benefitting from the computational flexibility of linear formulations. In the second part, the model is implemented in a seasonal dynamic zonally averaged climate model. It is found that, in response to a change between extreme high and low summer insolation orbits, the winter orbital change dominates over the opposite summer change for sea ice. For snow over land the shorter but more pronounced summer orbital change is shown to dominate.

  19. Effect of climate change and mollusc invasion on eutrophication and algae blooms in the lagoon ecosystems of the Baltic Sea

    NASA Astrophysics Data System (ADS)

    Aleksandrov, Sergei; Gorbunova, Julia; Rudinskaya, Lilia

    2015-04-01

    Coastal lagoons are most vulnerable to impacts of natural environmental and anthropogenic factors. The Curonian Lagoon and Vistula Lagoon are the largest coastal lagoons of the Baltic Sea, relating to the most highly productive water bodies of Europe. The Curonian Lagoon is choke mostly freshwater lagoon, while the Vistula Lagoon is restricted brackish water lagoon. In the last decades the nutrients loading changes, warming trend and biological invasions are observed. The researches (chlorophyll, primary production, nutrients, phytoplankton, benthos, etc) were carried out monthly since 1991 to 2014. The database includes 1600 stations in the Curonian Lagoon, 1650 stations in the Vistula Lagoon. Eutrophication and algae blooms are most important problems. Multiple reductions of nutrients loading from the watershed area in 1990s did not result in considerable improvement of the ecological situation in the lagoons. The Curonian Lagoon may be characterized as hypertrophic water body with "poor" water quality. Climate change in 1990s-2000s combined with other factors (freshwater, slow-flow exchange, high nutrients concentrations) creates conditions for Cyanobacteria "hyperblooms". Hyperbloom of Cyanophyta (average for the growing season Chl > 100 μg/l) were observed during 4 years in 1990s and 7 years in 2000s. The summer water temperature is the key environmental factor determining the seasonal and long-term variability of the primary production and algae blooms. Mean annual primary production in 2010-2014 (600 gC·m-2·year-1) is considerable higher, than in the middle of 1970s (300 gC·m-2·year-1). The local climate warming in the Baltic region caused ongoing eutrophication and harmful algae blooms in the Curonian Lagoon despite of significant reduction of nutrients loading in 1990s-2000s. Harmful algal blooms in July-October (chlorophyll to 700-3400 μg/l) result in deterioration of the water chemical parameters, death of fish in the coastal zone and pollution

  20. Modelling Late Cenozoic isostatic elevation changes in the Barents Sea and their implications for oceanic and climatic regimes: preliminary results

    NASA Astrophysics Data System (ADS)

    Butt, Faisal A.; Drange, Helge; Elverhøi, Anders; Otterå, Odd Helge; Solheim, Anders

    2002-08-01

    Late Cenozoic isostatic changes in the elevation of the Barents Sea are simulated using a numerical model. Isopach maps of the deposits off present-day Bear Island and Storfjorden troughs made earlier are used to calculate the thickness of sediment cover removed from the respective drainages basins at various time intervals during the last 2.3 Ma. Results indicate that Barents Sea was subaerially exposed at 2.3 Ma and major parts of it became submarine after 1 Ma. Barents Sea today receives around 40% of the warm and saline North Atlantic waters flowing into the Scotland-Greenland Ridge and about half of the Atlantic water entering the Arctic Ocean. It thus has an important role to play in the present-day ocean circulation pattern in the Polar North Atlantic region and water-mass transformations that take place in the Greenland-Iceland-Norwegian Sea and the Arctic Ocean. The effects of an uplifted Barents Sea on the oceanic regime and the Arctic sea-ice cover under the present-day forcings fields are studied using the Miami Isopycnic Coordinate Ocean Model. Preliminary results indicate that a subaerial Barents Sea causes an increased input of warm Atlantic waters into the Arctic Ocean through the Fram Strait which results in warming of the Atlantic water masses in the Arctic Ocean, followed by a reduction in the sea-ice cover. The obtained findings can be used to explain the apparent discrepancy in the late Cenozoic record of the sub-Arctic and Arctic regions whereby Fennoscandia, Iceland and Greenland are envisaged to have been covered by major ice sheets during late Pliocene whereas high Arctic areas such as Svalbard and NE Greenland were apparently free of any major ice.

  1. Understanding Climate Change and Sea Level: A Case Study of Middle School Student Comprehension and An Evaluation of Tide Gauges off the Panama Canal in the Pacific Ocean and Caribbean Sea

    NASA Astrophysics Data System (ADS)

    Millan-Otoya, Juan C.

    The present study had two main objectives. The first was to determine the degree of understanding of climate change, sea level and sea level rise among middle school students. Combining open-ended questions with likert-scaled questions, we identified student conceptions on these topics in 86 students from 7th and 8th grades during 2012 and 2013 before and after implementing a Curriculum Unit (CU). Additional information was obtained by adding drawings to the open-ended questions during the second year to gauge how student conceptions varied from a verbal and a visual perspective. Misconceptions were identified both pre- and post-CU among all the topics taught. Students commonly used climate and climate change as synonyms, sea level was often defined as water depth, and several students failed to understand the complexities that determine changes in sea level due to wind, tides, and changes in sea surface temperature. In general, 8th grade students demonstrated a better understanding of these topics, as reflected in fewer apparent misconceptions after the CU. No previous study had reported such improvement. This showed the value of implementing short lessons. Using Piaget's theories on cognitive development, the differences between 7th and 8th grade students reflect a transition to a more mature level which allowed students to comprehend more complex concepts that included multiple variables. The second objective was to determine if the frequency of sea level maxima not associated with tides over the last 100 years increased in two tide gauges located on the two extremes of the Panama canal, i.e. Balboa in the Pacific Ocean and Cristobal in the Caribbean Sea. These records were compared to time series of regional sea surface temperature, wind speed, atmospheric pressure, and El Nino-Southern Oscillation (ENSO), to determine if these played a role as physical drivers of sea level at either location. Neither record showed an increase in the frequency of sea level

  2. Impacts of Climate Change on Estuarine Habitats in the UK: Critical Evaluation of the Saltmarshes and Sea-Level Rise Model (SLAMM)

    NASA Astrophysics Data System (ADS)

    Pylarinou, A.; French, J.; Burningham, H.

    2013-12-01

    Estuarine wetland environments are at risk of significant transformation and loss due to sea-level rise and there is an increasing need to model such impacts. In a UK context, the relatively small size and morphological complexity of many estuaries necessitates a high spatial resolution but models must also be capable of efficient application over time scales of decades to centuries that correspond to widely used IPCC climate change scenarios. Little previous work of this kind has been carried out to date in the UK. An exception is the EU-funded BRANCH project, which simulated the drowning of intertidal topography, due to sea-level rise, and potential mudflat and saltmarsh responses to a change in inundation regime. However, this approach neglects the interplay of sea-level rise and sedimentation. Accordingly, this study investigates the potential of a more dynamic spatial landscape model to represent meso-scale impacts of sea-level rise on UK estuary environments. It takes as a starting point the Sea Level Affecting Marshes Model (SLAMM), which has been widely used in the USA. This is built around the US National Wetlands Inventory classification and adapting it to suit the tidal sedimentary environments and habitats typical of the UK requires changes to the source code. This paper presents results obtained from the application of an appropriately modified SLAMM code to contrasting estuarine environments in eastern England. The aim is to evaluate the ability of SLAMM to produce plausible projections of intertidal habitat change. The estuaries studied are covered by high-resolution altimetry data, and an extensive literature on their physical process regime allows the parameterisation of the various sub-models in SLAMM. A Matlab-based shell is used to perform an initial sensitivity analysis to better understand the nature of the modelled sea-level rise effects. This shell also provides a framework for Monte Carlo simulations forced by a set of UKCP09 sea-level rise

  3. Has anthropogenic land-cover change been a significant climate forcing in the past? - An assessment for the Baltic Sea catchment area based on a literature review

    NASA Astrophysics Data System (ADS)

    Gaillard, Marie-Jose; Kaplan, Jed O.; Kleinen, Thomas; Brigitte Nielsen, Anne; Poska, Anneli; Samuelsson, Patrick; Strandberg, Gustav; Trondman, Anna-Kari

    2015-04-01

    We reviewed the recent published scientific literature on land cover-climate interactions at the global and regional spatial scales with the aim to assess whether it is convincingly demonstrated that anthropogenic land-cover change (ALCC) has been (over the last centuries and millennia) a significant climate forcing at the global scale, and more specifically at the scale of the Baltic Sea catchment area. The conclusions from this review are as follows: i) anthropogenic land-cover change (ALCC) is one of the few climate forcings for which the net direction of the climate response in the past is still not known. The uncertainty is due to the often counteracting temperature responses to the many biogeophysical effects, and to the biogeochemical vs biogeophysical effects; ii) there is no indication that deforestation in the Baltic Sea area since AD 1850 would have been a major cause of the recent climate warming in the region through a positive biogeochemical feedback; iii) several model studies suggest that boreal reforestation might not be an effective climate warming mitigation tool as it might lead to increased warming through biogeophysical processes; iv) palaeoecological studies indicate a major transformation of the landscape by anthropogenic activities in the southern zone of the study region occurring between 6000 and 3000/2500 calendar years before present (cal. BP) (1) ; v) the only modelling study so far of the biogeophysical effects of past ALCCs on regional climate in Europe suggests that a deforestation of the magnitude of that reconstructed for the past (between 6000 and 200 cal BP) can produce changes in winter and summer temperatures of +/- 1°, the sign of the change depending on the season and the region (2). Thus, if ALCC and their biogeophysical effects did matter in the past, they should matter today and in the future. A still prevailing idea is that planting trees will mitigate climate warming through biogeochemical effects. Therefore, there is

  4. A Simple Model Framework to Explore the Deeply Uncertain, Local Sea Level Response to Climate Change. A Case Study on New Orleans, Louisiana

    NASA Astrophysics Data System (ADS)

    Bakker, Alexander; Louchard, Domitille; Keller, Klaus

    2016-04-01

    Sea-level rise threatens many coastal areas around the world. The integrated assessment of potential adaptation and mitigation strategies requires a sound understanding of the upper tails and the major drivers of the uncertainties. Global warming causes sea-level to rise, primarily due to thermal expansion of the oceans and mass loss of the major ice sheets, smaller ice caps and glaciers. These components show distinctly different responses to temperature changes with respect to response time, threshold behavior, and local fingerprints. Projections of these different components are deeply uncertain. Projected uncertainty ranges strongly depend on (necessary) pragmatic choices and assumptions; e.g. on the applied climate scenarios, which processes to include and how to parameterize them, and on error structure of the observations. Competing assumptions are very hard to objectively weigh. Hence, uncertainties of sea-level response are hard to grasp in a single distribution function. The deep uncertainty can be better understood by making clear the key assumptions. Here we demonstrate this approach using a relatively simple model framework. We present a mechanistically motivated, but simple model framework that is intended to efficiently explore the deeply uncertain sea-level response to anthropogenic climate change. The model consists of 'building blocks' that represent the major components of sea-level response and its uncertainties, including threshold behavior. The framework's simplicity enables the simulation of large ensembles allowing for an efficient exploration of parameter uncertainty and for the simulation of multiple combined adaptation and mitigation strategies. The model framework can skilfully reproduce earlier major sea level assessments, but due to the modular setup it can also be easily utilized to explore high-end scenarios and the effect of competing assumptions and parameterizations.

  5. On the relative importance of the climate change factors along the river Scheldt considering climate scenarios for upstream inland and downstream coastal (mean sea level and surge) boundary conditions

    NASA Astrophysics Data System (ADS)

    Ntegeka, V.; Willems, P.; Monbaliu, J.

    2012-04-01

    To improve on the efficacy of flood risk mitigation measures, it is essential to investigate the relative importance of the future impact pressures. This is more so in areas which are found to be hot spots for flooding. One such area was identified in the Scheldt region located in Belgium. The Dendermonde area is a place where both the downstream coastal and the upstream river flow boundary conditions interact and jointly control the flood risk. Downstream of this area, the coastal level changes include both the sea level rise and storm surge changes due to climate change impacts on the wind climate over the North Atlantic and North Sea region. Upstream of the Dendermonde area lies the Dender river which introduces an extra pressure on the Dendermonde area. Against this back drop, impact analysis was performed using a hydrodynamic model that accounts for such changes. The climate data for future scenarios were extracted from the climate databases PRUDENCE (http://prudence.dmi.dk), ENSEMBLES (http://www.ensembles-eu.org/), IPCC AR4 (www-pcmdi.llnl.gov/ipcc/about_ipcc.php) and CERA (CLM from MPI-M/MaD). Future changes were derived from the large ensemble set of climate model runs and their effects simulated in the hydrodynamic model based on statistically processed climate change scenarios of sea level rise, SLP change and related storm surge changes and upstream runoff due to changes in rainfall and potential evapotranspiration. Changes in SLP were transferred to changes in storm surges at the Scheldt mouth (at Vlissingen) based on a correlation model between the SLP at the Baltic Sea and the storm surge level. This model was derived after analysis of SLP composite maps and SLP-surge correlation maps for days where the surge exceeds given thresholds (for different return periods). Correlations between the inland (rainfall, runoff) and coastal climatic changes were considered. The impact analysis to analyze the importance of the pressures for the Dendermonde area was

  6. The water fluxes of the Yellow River to the sea in the past 50 years, in response to climate change and human activities.

    PubMed

    Jiongxin, Xu

    2005-05-01

    Since the 1970s, the water fluxes to the sea of the Yellow River have declined significantly. Based on data of precipitation, air temperature, the measured and "natural" river flow, the water diversion and consumption, and the areas of erosion and sediment control measures over the drainage basin, water fluxes to the sea of the Yellow River are studied in relation with the influences of changing climate and human activities. The Yellow River basin can be divided into different water source areas; multiple regression indicates that the variation in precipitation over different water source areas has different effect on water fluxes to the sea. In the period between 1970 and 1997, averaged air temperature over the whole Yellow River increased by about 1.0 degree C, from 16.5 degrees C to 17.5 degrees C, a factor that is negatively correlated with the water yield of the Yellow River. Water diversion and consumption has sharply increased and resulted in a significant decline in the water fluxes to the sea. Since the 1960s, erosion and sediment control measures have been practiced over the drainage basin. This factor, to a lesser degree, is also responsible for the decrease in water fluxes to the sea. A multiple regression equation has been established to estimate the change in water fluxes to the sea caused by the changes in precipitation, air temperature, water diversion and consumption, erosion, and sediment control measures, indicating that the contribution of water diversion and consumption to the variation in annual water flux to the sea is 41.3%, that of precipitation is 40.8%, that of temperature is 11.4%, and that of erosion and sediment control measures is 6.5%. PMID:15924206

  7. Analysis of sea level and sea surface temperature changes in the Black Sea

    NASA Astrophysics Data System (ADS)

    Betul Avsar, Nevin; Jin, Shuanggen; Kutoglu, Hakan; Erol, Bihter

    2016-07-01

    The Black Sea is a nearly closed sea with limited interaction with the Mediterranean Sea through the Turkish Straits. Measurement of sea level change will provide constraints on the water mass balance and thermal expansion of seawaters in response to climate change. In this paper, sea level changes in the Black Sea are investigated between January 1993 and December 2014 using multi-mission satellite altimetry data and sea surface temperature (SST) data. Here, the daily Maps of Sea Level Anomaly (MSLA) gridded with a 1/8°x1/8° spatial resolution from AVISO and the NOAA 1/4° daily Optimum Interpolation Sea Surface Temperature (OISST) Anomaly data set are used. The annual cycles of sea level and sea surface temperature changes reach the maximum values in November and January, respectively. The trend is 3.16±0.77 mm/yr for sea level change and -0.06±0.01°C/yr for sea surface temperature during the same 22-year period. The observed sea level rise is highly correlated with sea surface warming for the same time periods. In addition, the geographical distribution of the rates of the Black Sea level and SST changes between January 1993 and December 2014 are further analyzed, showing a good agreement in the eastern Black Sea. The rates of sea level rise and sea surface warming are larger in the eastern part than in the western part except in the northwestern Black Sea. Finally, the temporal correlation between sea level and SST time series are presented based on the Empirical Orthogonal Function (EOF) analysis.

  8. Climate change and intertidal wetlands.

    PubMed

    Ross, Pauline M; Adam, Paul

    2013-01-01

    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. PMID:24832670

  9. Climate change and intertidal wetlands.

    PubMed

    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. Climate Change and Intertidal Wetlands

    PubMed Central

    Ross, Pauline M.; Adam, Paul

    2013-01-01

    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. PMID:24832670

  11. Examining the reproducibility of stable isotope ratios in the marine bivalve, Astarte borealis, from populations in the White Sea, Russia: implications for biological consequences of climate change

    NASA Astrophysics Data System (ADS)

    McNabb, Justin; Surge, Donna

    2015-04-01

    Shells of the marine bivalve, Astarte, are uniquely suited to investigate links between environmental/climate change and biological consequences because of their change in size and biogeographic distribution through time. For example, are there corresponding changes in lifespan and biogeographic distribution depending on warm vs. cold climate states? Does warm vs. cold climate state result in longer or shorter lifespans? Early studies of Astarte have documented a decrease in shell size through geologic time. Modern specimens are much smaller than those from the mid Pliocene at similar latitudes. Astarte had a wide latitudinal and cosmopolitan distribution in the western North Atlantic during the Oligocene to Pliocene. During the early Pleistocene, most of the warm-water species became extinct, and today, their biogeographic distribution is mostly restricted to the northern Pacific, Atlantic, and Arctic Oceans. To answer questions linking biological consequences and climate change, we must first decipher ontogenetic changes in shell growth of modern specimens. Preliminary data using isotope sclerochronology identified slowed shell growth from late summer to winter in modern specimens from the White Sea, Russia, possibly triggered by increasing freshwater input and decreasing temperatures. Here, we present new data examining the reproducibility of isotopic time series and season of slowed growth among modern individuals collected at the same time from the same population.

  12. Potential impact of climate change on the Intra-Americas Sea: Part 2. Implications for Atlantic bluefin tuna and skipjack tuna adult and larval habitats

    NASA Astrophysics Data System (ADS)

    Muhling, Barbara A.; Liu, Yanyun; Lee, Sang-Ki; Lamkin, John T.; Roffer, Mitchell A.; Muller-Karger, Frank; Walter, John F., III

    2015-08-01

    Increasing water temperatures due to climate change will likely have significant impacts on distributions and life histories of Atlantic tunas. In this study, we combined predictive habitat models with a downscaled climate model to examine potential impacts on adults and larvae of Atlantic bluefin tuna (Thunnus thynnus) and skipjack tuna (Katsuwonus pelamis) in the Intra-Americas Sea (IAS). An additional downscaled model covering the 20th century was used to compare habitat fluctuations from natural variability to predicted future changes under two climate change scenarios: Representative Concentration Pathway (RCP) 4.5 (medium-low) and RCP 8.5 (high). Results showed marked temperature-induced habitat losses for both adult and larval bluefin tuna on their northern Gulf of Mexico spawning grounds. In contrast, habitat suitability for skipjack tuna increased as temperatures warmed. Model error was highest for the two skipjack tuna models, particularly at higher temperatures. This work suggests that influences of climate change on highly migratory Atlantic tuna species are likely to be substantial, but strongly species-specific. While impacts on fish populations remain uncertain, these changes in habitat suitability will likely alter the spatial and temporal availability of species to fishing fleets, and challenge equilibrium assumptions of environmental stability, upon which fisheries management benchmarks are based.

  13. Evidence of the observed change in the atmosphere-ocean interactions over the South China Sea during summer in a regional climate model

    NASA Astrophysics Data System (ADS)

    Jang, Hye-Yeong; Yeh, Sang-Wook; Chang, Eun-Chul; Kim, Baek-Min

    2016-10-01

    The South China Sea plays a key role to change the precipitation variability in East Asia by influencing the northward moisture transport. Previous study found that there exist changes in atmosphere-ocean interactions over the South China Sea (SCS) before and after the late 1990s during boreal summer (June-July-August) in the observations. This study further supports such changes using two simulations of the atmospheric regional climate model (RCM) forced by historical sea surface temperature (SST). The control run is forced by historical SSTs, which are prescribed in the entire domain in the RCM. In addition to the control run, an additional idealized experiment is conducted, i.e., the historical SSTs are prescribed in the SCS only and the climatological SST is prescribed outside the SCS to examine the changes in the atmosphere-ocean interactions in the SCS. It is found that the simultaneous correlation coefficient between SST and precipitation changes significantly over the SCS before and after the late 1990s. This result supports the notion that there are significant changes in atmosphere-ocean interactions over the SCS before and after the late 1990, which affects the ability of the RCM to simulate precipitation variability accurately relative to observation. This result implies that the simulations of atmospheric circulation model results forced by observed SST before the late 1990 should be cautiously interpreted because the observed SST anomalies are forced by the atmosphere.

  14. Hindcasting and forecasting macrofauna species distribution for the Jade Bay tidal basin (North Sea, Germany) in response to climatic and environmental changes

    NASA Astrophysics Data System (ADS)

    Singer, Anja; Schückel, Ulrike; Beck, Melanie; Bleich, Oliver; Brumsack, Hans-J.; Freund, Holger; Geimecke, Christina; Lettmann, Karsten; Millat, Gerald; Staneva, Joanna; Vanselow, Anna; Westphal, Heiko; Wolff, Jörg-O.; Wurpts, Andreas; Kröncke, Ingrid

    2016-04-01

    During the last decades severe climatic and environmental changes have been monitored for the Jade Bay (German Wadden Sea), causing pronounced changes in the abundance and spatial distribution of characteristic benthic species. Due to their relatively sessile habit, benthic species are ideal organisms for small-scale species distribution modelling (SDM) and important indicators for environmental changes and disturbances. In a first step, the present distribution (representing 2009) was modelled for 10 characteristic macrofauna (> 0.5 mm) species, built on statistical relations between species presences and 11 high-resolution environmental grids. Here, five different presence-absence modelling algorithms were merged (GLM, GBM, RF, MARS, ANN) within the ensemble forecasting platform 'biomod2'. In a second step, the past distribution scenario was reconstructed for the 1970s in order to evaluate the hindcast model results with independent macrofauna data from the 1970s. In a third step, the future macrofauna distribution (representing 2050) was forecasted under potential future habitat conditions, i.e. ongoing sea-level rise and changing biogenic structures (seagrass and mussel beds). Submergence time and sediment characteristics correlated most significantly with the modelled macrofauna distribution at the study site, followed by nutrient supply and topography. The historical macrofauna data evaluated the past distribution scenario model results. Climate change induced sea-level rise and its local implications on the Jade Bay (increased sediment load, rise in the tidal height) explained the changes in the macrofauna distribution patterns since the last four decades. The forecast scenario revealed clear species distribution shifts, range size changes and niche overlap changes.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Climate induced changes on the hydrology of the southern coast of Mediterranean Sea, Alexandria - Matrouh Governorates, Egypt

    NASA Astrophysics Data System (ADS)

    Mabrouk, Badr; Ludwig, Ralf

    2014-05-01

    The Nile Delta is one of the most complex, fragile and densely populated landscapes. It has suffered from abrupt environmental changes including sea level rise, sea water intrusion, and dramatic drawdown in groundwater levels due to severe pumping. The western part of Nile Delta's coast, from Alexandria to Marsa Matruh Governorates, is considered as one of the most vulnerable regions in Nile Delta. Environmentally complicated risks on water and soil coincide with suffering from strategic management problems. The general lack of studies linking sea level rise with socioeconomic impact cause large uncertainties. Such impacts became very critical recently, as subsidence and successive step sliding in the northern coast cause catastrophic disasters in areas with high population and socio-economic importance. Western Coast of Nile Delta is characterized by a succession of limestone and oolitic limestone which is extremely fragile and vulnerable to degradation in addition to dissolution by saline water. This study deals with studying the effect of global warming, sea level rise and severe pumping on the studied area. Examples will be given for soil degradation, subsidence, surface sliding, creeps successive step sliding, and sinkholes due to dissolving and fracturing of the limestone plateau.

  17. "Dangerous" Climate Change

    NASA Astrophysics Data System (ADS)

    Mastrandrea, M. D.

    2003-12-01

    Current climate change mitigation policy decisions must be made despite layers of uncertainty. Modeling of future climate, projections for future economic growth and greenhouse gas emissions, and characterizations of the interactions and feedbacks within the coupled social-natural system all contain uncertain components. Researchers communicating with policymakers have learned that, instead of presenting "best guesses" or other point estimates, uncertainty assignments require such techniques as probability distributions of outcomes and quantitatively defined descriptions of subjective confidence. We present a quantification of "dangerous" climate change, a term important in policy discussions. Article 2 of the United Nations Framework Convention on Climate Change expresses the opinion of the signing Parties that steps be taken to "prevent dangerous anthropogenic interference with the climate system," but the Convention did not specify what constitutes the value judgment of being "dangerous." We present one possible definition. A threshold for "dangerous" climate change is a clear tool for evaluating the need for and impact of proposed climate policy. Monte Carlo analyses with a simple integrated assessment model demonstrate that endogenously calculated climate policy controls appreciably reduce the probability of "dangerous" climate change. Under mid-range assumptions, climate policy reduces the probability of "dangerous" climate change by 30-50%.

  18. Coping with climate change

    USGS Publications Warehouse

    Prato, Tony; Fagre, Daniel B.

    2006-01-01

    Climate is not the only factor in the deterioration of natural systems.We are making big changes to the landscape, altering land use and land cover in major ways. These changes combined present a challenge to environmental management. Adaptive management is a scientific approach to managing the adverse impacts of climate and landscape change.

  19. Our Changing Climate

    ERIC Educational Resources Information Center

    Newhouse, Kay Berglund

    2007-01-01

    In this article, the author discusses how global warming makes the leap from the headlines to the classroom with thought-provoking science experiments. To teach her fifth-grade students about climate change, the author starts with a discussion of the United States' local climate. They extend this idea to contrast the local climate with others,…

  20. Calcrete and coal in late Carboniferous cyclothems of Nova Scotia, Canada. Climate and sea-level changes linked

    SciTech Connect

    Tandon, S.K. ); Gibling, M.R. )

    1994-08-01

    Modern tropical peats require continuity of precipitation for accumulation, whereas calcretes and calcic vertisols require strongly seasonal conditions. The 20-30-m-thick cyclothems of the Sydney basin, Nova Scotia, Canada, show a systematic alternation of coals and other hydromorphic paleosols with calcretes and calcic vertisols. This implies strong variation in seasonality during the duration of a cyclothem, estimated at 200 ka. In at least one cyclothem, calcic paleosols formed on an interfluve adjacent to a paleovalley cut through marine strata, suggesting that a more seasonal and probably drier climate prevailed during sea-level lowstand. The calcic paleosols are estimated to have formed during periods of 10[sup 4] yr, possibly indicative of partial control by obliquity and precessional cycles. 27 refs., 5 figs., 1 tab.

  1. Impact of climate change on ecological quality indicators and biogeochemical fluxes in the Baltic sea: a multi-model ensemble study.

    PubMed

    Meier, H E Markus; Müller-Karulis, Bärbel; Andersson, Helén C; Dieterich, Christian; Eilola, Kari; Gustafsson, Bo G; Höglund, Anders; Hordoir, Robinson; Kuznetsov, Ivan; Neumann, Thomas; Ranjbar, Zohreh; Savchuk, Oleg P; Schimanke, Semjon

    2012-09-01

    Multi-model ensemble simulations using three coupled physical-biogeochemical models were performed to calculate the combined impact of projected future climate change and plausible nutrient load changes on biogeochemical cycles in the Baltic Sea. Climate projections for 1961-2099 were combined with four nutrient load scenarios ranging from a pessimistic business-as-usual to a more optimistic case following the Helsinki Commission's (HELCOM) Baltic Sea Action Plan (BSAP). The model results suggest that in a future climate, water quality, characterized by ecological quality indicators like winter nutrient, summer bottom oxygen, and annual mean phytoplankton concentrations as well as annual mean Secchi depth (water transparency), will be deteriorated compared to present conditions. In case of nutrient load reductions required by the BSAP, water quality is only slightly improved. Based on the analysis of biogeochemical fluxes, we find that in warmer and more anoxic waters, internal feedbacks could be reinforced. Increased phosphorus fluxes out of the sediments, reduced denitrification efficiency and increased nitrogen fixation may partly counteract nutrient load abatement strategies.

  2. Changes in planktic and benthic foraminifer assemblages in the Gulf of Lions, off south France: Response to climate and sea level change from MIS 6 to MIS 11

    NASA Astrophysics Data System (ADS)

    Cortina, Aleix; Sierro, Francisco Javier; Filippelli, Gabriel; Flores, José Abel; Berné, Serge

    2013-04-01

    A multidisciplinary study involving micropaleontological and geochemical tools was carried out in borehole PRGL1 (Promess 1), with the aim of reconstructing the impact of climate change and sea level variation between 133 ka and 406 ka in the upper slope of the Gulf of Lions. We used factor analysis to obtain three main benthic assemblages related to eutrophic, mesotrophic, and oxygenated environments; planktic foraminifers were grouped as warm-water and cold-turbulent species. These results were compared with records of CaCO3 and major and trace elements (Al, Ca, K, Sr) as well as the C/N ratio of organic matter. Power and cross-spectral analysis showed a straightforward relationship between precession minima and thermal stratification of the water column as well as the occurrence of eutrophic bottom conditions during lowstand periods and mesotrophic environments at times of highstand. These eutrophic-mesotrophic oscillations, usually driven by global eustatic change, also involved regional variations in CaCO3 source to this environment. During periods of precession maxima, enhancement of northwesterly winds increased primary productivity by mixing, enhancing the percentage of cold-turbulent species in the water column and the proportion of oxygenated benthic species on the bottom. During interglacial stages, these events were recorded by lower biogenic carbonate at the expense of higher silicate-related components most likely due to a higher supply from Pyrenees rivers. The record of oxygenated benthic species can be a good proxy to monitor past changes in Winter Intermediate Water dynamics driven by northwesterly winds.

  3. Climate Change in Prehistory

    NASA Astrophysics Data System (ADS)

    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.

  4. Probabilistic Projections of Future Sea-Level Change and Their Implications for Flood Risk Management: Insights from the American Climate Prospectus

    NASA Astrophysics Data System (ADS)

    Kopp, R. E., III; Delgado, M.; Horton, R. M.; Houser, T.; Little, C. M.; Muir-Wood, R.; Oppenheimer, M.; Rasmussen, D. M., Jr.; Strauss, B.; Tebaldi, C.

    2014-12-01

    Global mean sea level (GMSL) rise projections are insufficient for adaptation planning; local decisions require local projections that characterize risk over a range of timeframes and tolerances. We present a global set of local sea level (LSL) projections to inform decisions on timescales ranging from the coming decades through the 22nd century. We present complete probability distributions, informed by a combination of expert community assessment, expert elicitation, and process modeling [1]. We illustrate the application of this framework by estimating the joint distribution of future sea-level change and coastal flooding, and associated economic costs [1,2]. In much of the world in the current century, differences in median LSL projections are due primarily to varying levels of non-climatic uplift or subsidence. In the 22nd century and in the high-end tails, larger ice sheet contributions, particularly from the Antarctic ice sheet (AIS), contribute significantly to site-to-site differences. Uncertainty in GMSL and most LSL projections is dominated by the uncertain AIS component. Sea-level rise dramatically reshapes flood risk. For example, at the New York City (Battery) tide gauge, our projections indicate a likely (67% probability) 21st century LSL rise under RCP 8.5 of 65--129 cm (1-in-20 chance of exceeding 154 cm). Convolving the distribution of projected sea-level rise with the extreme value distribution of flood return periods indicates that this rise will cause the current 1.80 m `1-in-100 year' flood event to occur an expected nine times over the 21st century -- equivalent to the expected number of `1-in-11 year' floods in the absence of sea-level change. Projected sea-level rise for 2100 under RCP 8.5 would likely place 80-160 billion of current property in New York below the high tide line, with a 1-in-20 chance of losses >190 billion. Even without accounting for potential changes in storms themselves, it would likely increase average annual storm

  5. Numerical modelling of climate change impacts on freshwater lenses on the North Sea Island of Borkum using hydrological and geophysical methods

    NASA Astrophysics Data System (ADS)

    Sulzbacher, H.; Wiederhold, H.; Siemon, B.; Grinat, M.; Igel, J.; Burschil, T.; Günther, T.; Hinsby, K.

    2012-10-01

    A numerical, density dependent groundwater model is set up for the North Sea Island of Borkum to estimate climate change impacts on coastal aquifers and especially the situation of barrier islands in the Wadden Sea. The database includes information from boreholes, a seismic survey, a helicopter-borne electromagnetic (HEM) survey, monitoring of the freshwater-saltwater boundary by vertical electrode chains in two boreholes, measurements of groundwater table, pumping and slug tests, as well as water samples. Based on a statistical analysis of borehole columns, seismic sections and HEM, a hydrogeological model is set up. The groundwater model is developed using the finite-element programme FEFLOW. The density dependent groundwater model is calibrated on the basis of hydraulic, hydrological and geophysical data, in particular spatial HEM and local monitoring data. Verification runs with the calibrated model show good agreement between measured and computed hydraulic heads. A good agreement is also obtained between measured and computed density or total dissolved solids data for both the entire freshwater lens on a large scale and in the area of the well fields on a small scale. For simulating future changes in this coastal groundwater system until the end of the current century, we use the climate scenario A2, specified by the Intergovernmental Panel on Climate Change and, in particular, the data for the German North Sea coast. Simulation runs show proceeding salinisation with time beneath the well fields of the two waterworks Waterdelle and Ostland. The modelling study shows that the spreading of well fields is an appropriate protection measure against excessive salinisation of the water supply until the end of the current century.

  6. Potential effects of temperature on the benthic infaunal community on the southeastern Bering Sea shelf: Possible impacts of climate change

    NASA Astrophysics Data System (ADS)

    Coyle, K. O.; Konar, B.; Blanchard, A.; Highsmith, R. C.; Carroll, J.; Carroll, M.; Denisenko, S. G.; Sirenko, B. I.

    2007-11-01

    In the late 1950s, Soviet researchers collected benthic infaunal samples from the southeastern Bering Sea shelf. Approximately 17 years later, researchers at University of Alaska Fairbanks also sampled the region to assess infaunal biomass and abundance. Here, the two data sets were examined to document patterns and reveal any consistent differences in infaunal biomass among major feeding groups between the two time periods. No significant differences in the geometric mean biomass of all taxa pooled were indicated between the two study periods (1958-1959=49.1 g m -2; 1975-1976=60.8 g m -2; P=0.14); however, significant differences were observed for specific functional groups, namely carnivores, omnivores and surface detritivores. Of the 64 families identified from both data sets from all functional groups, 21 showed statistically significant ( P⩽0.05) differences in mean biomass. Of the 21 families showing significant differences, 19 (91%) of the families had higher mean biomass in the 1975-1976 data set. The above differences suggest a trend toward higher overall infaunal biomass for specific functional groups during mid 1970s compared with the late 1950s. Temperature measurements and literature data indicate that the mid-1970s was an unusually cold period relative to the period before and after, suggesting a mechanistic link between temperature changes and infaunal biomass. Food-web relationships and ecosystem dynamics in the southeastern Bering Sea indicate that during cold periods, infaunal biomass will be elevated relative to warm periods due to elevated carbon flux to the benthos and exclusion of benthic predators on infaunal invertebrates by the cold bottom water on the shelf. As long-term observations of temperature and sea-ice cover indicate a secular warming trend on the Bering Sea shelf, the potential changes in food-web relationships could markedly alter trophic structure and energy flow to apex consumers, potentially impacting the commercial, tourist

  7. The Response to Climate Change of the Cold Arctic Halocline, Shielding Sea Ice from the Warm Deep Water Below

    NASA Astrophysics Data System (ADS)

    Reddy, T. E.; Palmer, M. A.; Arrigo, K. R.; Holland, D. M.

    2011-12-01

    The cold halocline layer of the Arctic Ocean shields the ice cover from an upward flux of heat from the underlying warm Atlantic water. Since this cold layer insulates the surface layer and ice from the heat below, changes in heat content and depth of this layer may have a profound effect on the surface energy and mass balance of sea ice in this region. In contrast to the halocline in the Eastern Arctic basins, the halocline in the Canadian basin is more complex with waters coming from both the Atlantic and Pacific. In this research study, we explored the physical environment of two Arctic shelf regions: the Alaskan Shelf and the Mackenzie Shelf. Here, we compare results from the Mackenzie Alaskan Shelf System (MASS) model (with which we run coupled ocean-ice-atmosphere simulations) to field data from two sets of cruises to the area: the Canadian Arctic Shelf Exchange Study (CASES) to the Mackenzie Shelf and Beaufort Sea and the Shelf-Basin Interaction (SBI) study to the Alaskan Shelf and Chukchi and Beaufort Seas. We investigate the physical connections of the shelves, slopes, and deep basins using results from our model. Heat content in the Atlantic waters below the halocline is large enough to begin melting ice from below if this barrier is weakened or perturbed. One key goal of this study is exploring how this barrier reacts to potential future changes, including the singular and combined affects of increased air temperature and increased wind speed, as well as decreased ice cover. While the perturbations had little effect on the Alaskan Shelf, results of note on the Mackenzie Shelf include a thickening of the halocline in the spring in the increased wind run and a diminishment of the halocline in the fall in both runs in which temperature increased (increased temperature only and increased winds and temperature together). The surface waters were notably warmer in both of these increased temperature runs, with tremendous implications for sea ice cover.

  8. Climate change 2007 - mitigation of climate change

    SciTech Connect

    Metz, B.; Davidson, O.; Bosch, P.; Dave, R.; Meyer, L.

    2007-07-01

    This volume of the Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) provides a comprehensive, state-of-the-art and worldwide overview of scientific knowledge related to the mitigation of climate change. It includes a detailed assessment of costs and potentials of mitigation technologies and practices, implementation barriers, and policy options for the sectors: energy supply, transport, buildings, industry, agriculture, forestry and waste management. It links sustainable development policies with climate change practices. This volume will again be the standard reference for all those concerned with climate change. Contents: Foreword; Preface; Summary for policymakers; Technical Summary; 1. Introduction; 2. Framing issues; 3. Issues related to mitigation in the long term context; 4. Energy supply; 5. Transport and its infrastructure; 6. Residential and commercial buildings; 7. Industry; 8. Agriculture; 9. Forestry; 10. Waste management; 11. Mitigation from a cross sectoral perspective; 12. Sustainable development and mitigation; 13. Policies, instruments and co-operative agreements. 300 figs., 50 tabs., 3 annexes.

  9. Climate change and mitigation.

    PubMed

    Nibleus, Kerstin; Lundin, Rickard

    2010-01-01

    Planet Earth has experienced repeated changes of its climate throughout time. Periods warmer than today as well as much colder, during glacial episodes, have alternated. In our time, rapid population growth with increased demand for natural resources and energy, has made society increasingly vulnerable to environmental changes, both natural and those caused by man; human activity is clearly affecting the radiation balance of the Earth. In the session "Climate Change and Mitigation" the speakers offered four different views on coal and CO2: the basis for life, but also a major hazard with impact on Earth's climate. A common denominator in the presentations was that more than ever science and technology is required. We need not only understand the mechanisms for climate change and climate variability, we also need to identify means to remedy the anthropogenic influence on Earth's climate.

  10. Ocean Observations of Climate Change

    NASA Astrophysics Data System (ADS)

    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.

  11. Role of Low Frequency Sea Surface Temperature Modes with a Changing Climate in Modulating Atlantic Hurricane Activity

    SciTech Connect

    LaRow, Timothy

    2014-08-03

    The SSTs used in our study come from the Community Climate System Model version 4 (CCSM4) (Gent et al 2011) and from the Canadian Centre for Climate Modeling and Analysis (CanESM2) (Chylek et al20ll) climate models from the fifth Coupled Model Intercomparison Project (CMIP5) (Taylor et al2012). We've examined the tropical cyclones using both the historical simulation that employs volcanic and aerosol forcing as well as the representative concentration pathway 4.5 (RCP4.5). In addition, we've compared the present day North Atlantic tropical cyclone metrics from a previous study (LaRow, 2013) to these climate change experiments. The experimental setup is shown in Table 1. We considered the CMIP5 experiment number '3.2 historical' (Taylor et al,201l), which provides simulations of the recent past (1850-2005). The second set of CMIP5 SSTs is the RCp4.5 experiment where the radiative forcing stabilizes at 45W m-2 after 2100 (experiment number 4.1 in Taylor etal2}ll).

  12. An integrated multi-parameter monitoring approach for the quantification and mitigation of the climate change impact on the coasts of Eastern Crete, S. Aegean Sea (Project AKTAIA)

    NASA Astrophysics Data System (ADS)

    Ghionis, George; Alexandrakis, George; Karditsa, Aikaterini; Sifnioti, Dafni; Vousdoukas, Michalis; Andreadis, Olympos; Petrakis, Stelios; Poulos, Serafim; Velegrakis, Adonis; Kampanis, Nikolaos; Lipakis, Michalis

    2014-05-01

    The AKTAIA project aims at the production of new knowledge regarding the forms of manifestation of the climate change and its influence on the stability and evolution of the coastal landforms along the shoreline of eastern Crete (approximate length: 757 km), taking into account the various aspects of human intervention. Aerial photographs, satellite images and orthophotomaps have been used to produce a detailed coastline map and to study the morphological characteristics of the coastal zone of Eastern Crete. More than 100 beach zones have been visited during three field campaigns, which included geomorphological and human intervention mapping, topographic, meteorological and oceanographic measurements and sedimentological sampling and observations. In addition, two pilot sites (one in the north and one in the south part of Crete) are being monitored, via the installation of coastal video monitoring systems, shore-based meteorological stations and wave-tide recorders installed in the nearshore zone. Detailed seafloor mapping with the use of side scan sonar and scuba diving and bathymetric surveys were conducted in the two pilot sites. Meteorological and oceanographic data from all existing land-based meteorological stations, oceanographic buoys and the ERA-interim dataset are used to determine the wind and wave climate of each beach. The collected climatic, sedimentological and coastal environmental data are being integrated in a GIS database that will be used to forecast the climatic trends in the area of Crete for the next decades and to model the impact of the climatic change on the future evolution of the coastal zone. New methodologies for the continuous monitoring of land-sea interaction and for the quantification of the loss of sensitive coastal zones due to sea-level rise and a modified Coastal Vulnerability Index for a comparative evaluation of the vulnerability of the coasts are being developed. Numerical modelling of the nearshore hydrodynamics and the

  13. Responding to the Consequences of Climate Change

    NASA Technical Reports Server (NTRS)

    Hildebrand, Peter H.

    2011-01-01

    The talk addresses the scientific consensus concerning climate change, and outlines the many paths that are open to mitigate climate change and its effects on human activities. Diverse aspects of the changing water cycle on Earth are used to illustrate the reality climate change. These include melting snowpack, glaciers, and sea ice; changes in runoff; rising sea level; moving ecosystems, an more. Human forcing of climate change is then explained, including: greenhouse gasses, atmospheric aerosols, and changes in land use. Natural forcing effects are briefly discussed, including volcanoes and changes in the solar cycle. Returning to Earth's water cycle, the effects of climate-induced changes in water resources is presented. Examples include wildfires, floods and droughts, changes in the production and availability of food, and human social reactions to these effects. The lk then passes to a discussion of common human reactions to these forecasts of climate change effects, with a summary of recent research on the subject, plus several recent historical examples of large-scale changes in human behavior that affect the climate and ecosystems. Finally, in the face for needed action on climate, the many options for mitigation of climate change and adaptation to its effects are presented, with examples of the ability to take affordable, and profitable action at most all levels, from the local, through national.

  14. Movement of deep-sea coral populations on climatic timescales

    NASA Astrophysics Data System (ADS)

    Thiagarajan, Nivedita; Gerlach, Dana; Roberts, Mark L.; Burke, Andrea; McNichol, Ann; Jenkins, William J.; Subhas, Adam V.; Thresher, Ronald E.; Adkins, Jess F.

    2013-06-01

    During the past 40,000 years, global climate has moved into and out of a full glacial period, with the deglaciation marked by several millennial-scale rapid climate change events. Here we investigate the ecological response of deep-sea coral communities to both glaciation and these rapid climate change events. We find that the deep-sea coral populations of Desmophyllum dianthus in both the North Atlantic and the Tasmanian seamounts expand at times of rapid climate change. However, during the more stable Last Glacial Maximum, the coral population globally retreats to a more restricted depth range. Holocene populations show regional patterns that provide some insight into what causes these dramatic changes in population structure. The most important factors are likely responses to climatically driven changes in productivity, [O2] and [CO32-].

  15. The Sand Seas of northern China: Important sinks and sources of global sediment fluxes and their changing roles during different climate conditions of Late Quaternary

    NASA Astrophysics Data System (ADS)

    Yang, X.

    2014-12-01

    Although the occurrence of aeolian sands in sedimentary sequences has been widely used as indicators of desert formation or proxies of desert climate, one should be aware that accumulation of aeolian sands does occur along river channels, in lake shores not necessarily associated with arid environment. Our ongoing geomorphological and paleoenvironmental studies in the deserts of northern China reconfirm that formation of sand seas is dependent on not only erodibility (arising from bare surface due to aridity) and wind power but more importantly sand availability related to sediment cycles under interactions between fluvial, lacustrine and aeolian processes. Here we present our ongoing geomorphological and paleoclimatic research on the Late Quaternary landscape and climatic changes in the Taklamkan Desert of northwestern China, the largest sand sea of China in arid zone, and in the Hunshandake Sandy Land at the east part of the Asian mid-latitude desert belt under semiarid climate. We find out that the occurrence of tall sand dunes in the over 300,000 km2 large Taklamakan Sand Sea is closely related to the sites of intensive fluvial sedimentation and convergence zone of surface winds. In the case of Hunshandake, the dunes (although much smaller) mainly occur along the shorelines of the former lake basins, and sediment sources are generally limited because of open hydrological systems in the south and east portions of this desert. The sedimentological and geomorphological records suggest that the climate has changed between arid and less-arid conditions in both of these deserts during Late Quaternary. Under wetter conditions the Taklamakan acts as an important sink of sediments brought by rivers with headwaters in the Tibetan Plateau and Tianshan, while under more arid conditions it acts as an important global sediment source whose dust is transported not only to East Asia and Pacific but also to Greenland ice via westerlies. The Hunshandake has the same pattern of

  16. Future climate of the Bering and Chukchi Seas projected by global climate models

    NASA Astrophysics Data System (ADS)

    Wang, Muyin; Overland, James E.; Stabeno, Phyllis

    2012-06-01

    Atmosphere-Ocean General Circulation Models (AOGCMs) are a major tool used by scientists to study the complex interaction of processes that control climate and climate change. Projections from these models for the 21st century are the basis for the Fourth Assessment Report (AR4) produced by the Intergovernmental Panel on Climate Change (IPCC). Here, we use simulations from this set of climate models developed for the IPCC AR4 to provide a regional assessment of sea ice extent, sea surface temperature (SST), and surface air temperature (SAT) critical to future marine ecosystems in the Bering Sea and the Chukchi Sea. To reduce uncertainties associated with the model projections, a two-step model culling technique is applied based on comparison to 20th century observations. For the Chukchi Sea, data and model projections show major September sea ice extent reduction compared to the 20th century beginning now, with nearly sea ice free conditions before mid-century. Earlier sea ice loss continues throughout fall with major loss in December before the end of the 21st century. By 2050, for the eastern Bering Sea, spring sea ice extent (average of March to May) would be 58% of its recent values (1980-1999 mean). December will become increasingly sea ice free over the next 40 years. The Bering Sea will continue to show major interannual variability in sea ice extent and SST. The majority of models had no systematic bias in their 20th century simulated regional SAT, an indication that the models may provide considerable credibility for the Bering and the Chukchi Sea ecosystem projections. Largest air temperature increases are in fall (November to December) for both the Chukchi and the Bering Sea, with increases by 2050 of 3 °C for the Bering Sea and increases in excess of 5 °C for the Chukchi Sea.

  17. The Atlantic Climate Change Program

    SciTech Connect

    Molinari, R.L. ); Battisti, D. ); Bryan, K. ); Walsh, J. )

    1994-07-01

    The Atlantic Climate Change Program (ACCP) is a component of NOAA's Climate and Global Change Program. ACCP is directed at determining the role of the thermohaline circulation of the Atlantic Ocean on global atmospheric climate. Efforts and progress in four ACCP elements are described. Advances include (1) descriptions of decadal and longer-term variability in the coupled ocean-atmosphere-ice system of the North Atlantic; (2) development of tools needed to perform long-term model runs of coupled simulations of North Atlantic air-sea interaction; (3) definition of mean and time-dependent characteristics of the thermohaline circulation; and (4) development of monitoring strategies for various elements of the thermohaline circulation. 20 refs., 4 figs., 1 tab.

  18. Relative sea-level change, climate, and sequence boundaries: insights from the Kimmeridgian to Berriasian platform carbonates of Mount Salève (E France)

    NASA Astrophysics Data System (ADS)

    Bover-Arnal, Telm; Strasser, André

    2013-03-01

    The present study analyses the stratal architecture of the Late Jurassic (Kimmeridgian) to Early Cretaceous (Berriasian) sedimentary succession of Mount Salève (E France), and four Berriasian stratigraphic intervals containing four sequence-boundary zones reflecting lowering trends of the relative sea-level evolution. Massive Kimmeridgian limestones characterized by the presence of colonial corals appear to be stacked in an aggrading pattern. These non-bedded thick deposits, which are interpreted to have formed in balance between relative sea-level rise and carbonate accumulation, suggest a keep-up transgressive system. Above, well-bedded Tithonian-to-Berriasian peritidal carbonates reflect a general loss of accommodation. These strata are interpreted as a highstand normal-regressive unit. During the early phase of this major normal regression, the vertical repetition of upper intertidal/lower supratidal lithofacies indicates an aggrading depositional system. This is in agreement with an early stage of a highstand phase of relative sea level. The Berriasian sequence-boundary zones investigated (up to 4 m thick) developed under different climatic conditions and correspond to higher-frequency, forced- and normal-regressive stages of relative sea-level changes. According to the classical sequence-stratigraphic principles, these sequence-boundary zones comprise more than one candidate surface for a sequence boundary. Three sequence-boundary zones studied in Early Berriasian rocks lack coarse siliciclastic grains, contain a calcrete crust, as well as marly levels with higher abundances of illite with respect to kaolinite, and exhibit fossilized algal-microbial laminites with desiccation polygons. These sedimentary features are consistent with more arid conditions. A sequence-boundary zone interpreted for the Late Berriasian corresponds to a coal horizon. The strata above and below this coal contain abundant quartz and marly intervals with a higher kaolinite content

  19. Holocene tropical western Indian Ocean sea surface temperatures in covariation with climatic changes in the Indonesian region

    NASA Astrophysics Data System (ADS)

    Kuhnert, Henning; Kuhlmann, Holger; Mohtadi, Mahyar; Meggers, Helge; Baumann, Karl-Heinz; Pätzold, Jürgen

    2014-05-01

    The sea surface temperature (SST) of the tropical Indian Ocean is a major component of global climate teleconnections. While the Holocene SST history is documented for regions affected by the Indian and Arabian monsoons, data from the near-equatorial western Indian Ocean are sparse. Reconstructing past zonal and meridional SST gradients requires additional information on past temperatures from the western boundary current region. We present a unique record of Holocene SST and thermocline depth variations in the tropical western Indian Ocean as documented in foraminiferal Mg/Ca ratios and δ18O from a sediment core off northern Tanzania. For Mg/Ca and thermocline δ18O, most variance is concentrated in the centennial to bicentennial periodicity band. On the millennial time scale, an early to mid-Holocene (~7.8-5.6 ka) warm phase is followed by a temperature drop by up to 2°C, leading to a mid-Holocene cool interval (5.6-4.2 ka). The shift is accompanied by an initial reduction in the difference between surface and thermocline foraminiferal δ18O, consistent with the thickening of the mixed layer and suggestions of a strengthened Walker circulation. However, we cannot confirm the expected enhanced zonal SST gradient, as the cooling of similar magnitude had previously been found in SSTs from the upwelling region off Sumatra and in Flores air temperatures. The SST pattern probably reflects the tropical Indian Ocean expression of a large-scale climate anomaly rather than a positive Indian Ocean Dipole-like mean state.

  20. Late Pleistocene and early Holocene change in the Weddell Sea: a new climate record from the Patriot Hills, Ellsworth Mountains, West Antarctica

    NASA Astrophysics Data System (ADS)

    Turney, C. S.; Fogwill, C. J.; Rubino, M.; Etheridge, D. M.; van Ommen, T. D.; Moy, A. D.; Curran, M. A.

    2014-12-01

    The transition from the late Pleistocene to the Holocene (30 000-5000 years ago) was a period of considerable climate variability, which has been associated with changes in deep water formation and the intensity of the Meridional Overturning Circulation. Although numerous records exist across the North Atlantic region, few Antarctic ice core records have been obtained from the south. Here we exploit the potential of upwelling ancient ice - so-called blue ice areas (BIAs) - from the Patriot Hills in the Ellsworth Mountains to derive the first deuterium isotope record (dD) from continental Antarctica south of the Weddell Sea. Gas analysis and glaciological considerations provide a first relative chronology and provide new constraints on ice sheet dynamics in the region. Inferred temperature trends from the Patriot Hills BIA and snow pit suggest changing climate influences during the transition between the last glacial period and Holocene. Our results demonstrate the considerable potential of the Patriot Hills site for reconstructing past climate change in the south Atlantic region.

  1. What Is Climate Change?

    ERIC Educational Resources Information Center

    Beswick, Adele

    2007-01-01

    Weather consists of those meteorological events, such as rain, wind and sunshine, which can change day-by-day or even hour-by-hour. Climate is the average of all these events, taken over a period of time. The climate varies over different parts of the world. Climate is usually defined as the average of the weather over a 30-year period. It is when…

  2. Projected changes in tropical cyclones over Vietnam and the South China Sea using a 25 km regional climate model perturbed physics ensemble

    NASA Astrophysics Data System (ADS)

    Redmond, Grace; Hodges, Kevin I.; Mcsweeney, Carol; Jones, Richard; Hein, David

    2015-10-01

    The regional climate modelling system PRECIS, was run at 25 km horizontal resolution for 150 years (1949-2099) using global driving data from a five member perturbed physics ensemble (based on the coupled global climate model HadCM3). Output from these simulations was used to investigate projected changes in tropical cyclones (TCs) over Vietnam and the South China Sea due to global warming (under SRES scenario A1B). Thirty year climatological mean periods were used to look at projected changes in future (2069-2098) TCs compared to a 1961-1990 baseline. Present day results were compared qualitatively with IBTrACS observations and found to be reasonably realistic. Future projections show a 20-44 % decrease in TC frequency, although the spatial patterns of change differ between the ensemble members, and an increase of 27-53 % in the amount of TC associated precipitation. No statistically significant changes in TC intensity were found, however, the occurrence of more intense TCs (defined as those with a maximum 10 m wind speed >35 m/s) was found to increase by 3-9 %. Projected increases in TC associated precipitation are likely caused by increased evaporation and availability of atmospheric water vapour, due to increased sea surface and atmospheric temperature. The mechanisms behind the projected changes in TC frequency are difficult to link explicitly; changes are most likely due to the combination of increased static stability, increased vertical wind shear and decreased upward motion, which suggest a decrease in the tropical overturning circulation.

  3. Climate change and skin.

    PubMed

    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

  4. Climate change and skin.

    PubMed

    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

  5. [Climate change and health].

    PubMed

    Martens, Pim

    2009-01-01

    Despite the targets for greenhouse gas emissions agreed in Kyoto under the United Nations Framework Convention on Climate Change - again to be discussed in Copenhagen in December - climate change will still have serious effects on public health. The health effects of climate change will be noticeable also in the short run. Diseases which are transmitted by arthropod vectors will spread to more areas of the world than where they are present now. In addition, we will have to deal with allergies, deaths due to heat waves, diarrhoea and malnutrition. For this reason, every action is needed now in order to minimise the adverse effects on health.

  6. Climate Change Impacts in the Amazon. Review of scientific literature

    SciTech Connect

    2006-04-15

    The Amazon's hydrological cycle is a key driver of global climate, and global climate is therefore sensitive to changes in the Amazon. Climate change threatens to substantially affect the Amazon region, which in turn is expected to alter global climate and increase the risk of biodiversity loss. In this literature review the following subjects can be distinguished: Observed Climatic Change and Variability, Predicted Climatic Change, Impacts, Forests, Freshwater, Agriculture, Health, and Sea Level Rise.

  7. Climate Change: The Public Health Response

    PubMed Central

    Frumkin, Howard; Hess, Jeremy; Luber, George; Malilay, Josephine; McGeehin, Michael

    2008-01-01

    There is scientific consensus that the global climate is changing, with rising surface temperatures, melting ice and snow, rising sea levels, and increasing climate variability. These changes are expected to have substantial impacts on human health. There are known, effective public health responses for many of these impacts, but the scope, timeline, and complexity of climate change are unprecedented. We propose a public health approach to climate change, based on the essential public health services, that extends to both clinical and population health services and emphasizes the coordination of government agencies (federal, state, and local), academia, the private sector, and nongovernmental organizations. PMID:18235058

  8. The impact of Quaternary sea-level and climatic change on coastal alluvial fans in the Cabo de Gata ranges, southeast Spain

    NASA Astrophysics Data System (ADS)

    Harvey, Adrian M.; Silva, Pablo G.; Mather, Anne E.; Goy, Jose L.; Stokes, Martin; Zazo, Cari

    1999-05-01

    Conventionally, a fall in base level is seen as stimulating incision into the distal zones of alluvial fans. In the Cabo de Gata ranges of southeast Spain evidence exists to the contrary. Two sets of Quaternary coastal alluvial fans demonstrate the interaction between climatically-driven variations in the supply of sediment and eustatically-driven changes in base level. The fans are supplied from Miocene volcanic terrain within which no evidence can be found for major tectonic deformation during the period of fan development. The evolution of the east-coast fans has been affected by variations in sediment supply and changes in sea level. The west-coast fans were buffered from the effects of changes in sea level by coastal barriers. Three phases of past sedimentation can be identified on the fans. These can be differentiated on the basis of field observations of soil profiles (particularly colour of the B horizons and accumulation of CaCO 3), and laboratory analyses of sequential iron oxide extractions and magnetic mineral properties. The two earlier (major) sedimentation phases were coincident with global glacials (>ca. 135 ka and ca. 85-10 ka, based on the stratigraphy and uranium/thorium dating of the coastal sediments). High sea levels during the intervening interglacial and during the Holocene caused erosion of the distal zones of the east-coast fans which led to channel incision into the fan surfaces. On the west-coast fans no such incision occurred, simply proximal incision by small fanhead trenches. The youngest (relatively minor) phase of fan sedimentation has occurred during the Holocene. These contrasting contexts have produced differing styles of fans, with telescopic fan morphology on the east-coast and stacked morphology on the west-coast fans. The differences are reflected in the fan profiles, with steeper gradients dominating the east-coast fans, and extensive lower gradient distal surfaces on the west-coast fans. Fan morphometry, based on analysis

  9. Climate Change: An Activity.

    ERIC Educational Resources Information Center

    Lewis, Garry

    1995-01-01

    Presents a segment of the Geoscience Education booklet, Climate Change, that contains information and activities that enable students to gain a better appreciation of the possible effects human activity has on the Earth's climate. Describes the Terrace Temperatures activity that leads students through an investigation using foraminifera data to…

  10. Climate Change Made Simple

    ERIC Educational Resources Information Center

    Shallcross, Dudley E.; Harrison, Tim G.

    2007-01-01

    The newly revised specifications for GCSE science involve greater consideration of climate change. This topic appears in either the chemistry or biology section, depending on the examination board, and is a good example of "How Science Works." It is therefore timely that students are given an opportunity to conduct some simple climate modelling.…

  11. Creationism & Climate Change (Invited)

    NASA Astrophysics Data System (ADS)

    Newton, S.

    2009-12-01

    Although creationists focus on the biological sciences, recently creationists have also expanded their attacks to include the earth sciences, especially on the topic of climate change. The creationist effort to deny climate change, in addition to evolution and radiometric dating, is part of a broader denial of the methodology and validity of science itself. Creationist misinformation can pose a serious problem for science educators, who are further hindered by the poor treatment of the earth sciences and climate change in state science standards. Recent changes to Texas’ science standards, for example, require that students learn “different views on the existence of global warming.” Because of Texas’ large influence on the national textbook market, textbooks presenting non-scientific “different views” about climate change—or simply omitting the subject entirely because of the alleged “controversy”—could become part of K-12 classrooms across the country.

  12. Criminality and climate change

    NASA Astrophysics Data System (ADS)

    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.

  13. Global Climatic Change.

    ERIC Educational Resources Information Center

    Houghton, Richard A.; Woodwell, George M.

    1989-01-01

    Cites some of the evidence which suggests that the production of carbon dioxide and methane from human activities has begun to change the climate. Describes some measures which should be taken to stop or slow this progression. (RT)

  14. Global climate change

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1991-01-01

    Present processes of global climate change are reviewed. The processes determining global temperature are briefly described and the concept of effective temperature is elucidated. The greenhouse effect is examined, including the sources and sinks of greenhouse gases.

  15. Rapid climate change

    SciTech Connect

    Morantine, M.C.

    1995-12-31

    Interactions between insolation changes due to orbital parameter variations, carbon dioxide concentration variations, the rate of deep water formation in the North Atlantic and the evolution of the northern hemisphere ice sheets during the most recent glacial cycle will be investigated. In order to investigate this period, a climate model is being developed to evaluate the physical mechanisms thought to be most significant during this period. The description of the model sub-components will be presented. The more one knows about the interactions between the sub-components of the climate system during periods of documented rapid climate change, the better equipped one will be to make rational decisions on issues related to impacts on the environment. This will be an effort to gauge the feedback processes thought to be instrumental in rapid climate shifts documented in the past, and their potential to influence the current climate. 53 refs.

  16. Signatures of climate vs. sea-level change within incised valley-fill successions: Quaternary examples from the Texas GULF Coast

    NASA Astrophysics Data System (ADS)

    Blum, Michael D.; Aslan, Andres

    2006-08-01

    The passive margin Texas Gulf of Mexico Coastal Plain consists of coalescing late Pleistocene to Holocene alluvial-deltaic plains constructed by a series of medium to large fluvial systems. Alluvial-deltaic plains consist of the Pleistocene Beaumont Formation, and post-Beaumont coastal plain incised valleys. A variety of mapping, outcrop, core, and geochronological data from the extrabasinal Colorado River and the basin-fringe Trinity River show that Beaumont and post-Beaumont strata consist of a series of coastal plain incised valley fills that represent 100 kyr climatic and glacio-eustatic cycles. Valley fills contain a complex alluvial architecture. Falling stage to lowstand systems tracts consist of multiple laterally amalgamated sandy channelbelts that reflect deposition within a valley that was incised below highstand alluvial plains, and extended across a subaerially-exposed shelf. The lower boundary to falling stage and lowstand units comprises a composite valley fill unconformity that is time-transgressive in both cross- and down-valley directions. Coastal plain incised valleys began to fill with transgression and highstand, and landward translation of the shoreline: paleosols that define the top of falling stage and lowstand channelbelts were progressively onlapped and buried by heterolithic sandy channelbelt, sandy and silty crevasse channel and splay, and muddy floodbasin strata. Transgressive to highstand facies-scale architecture reflects changes through time in dominant styles of avulsion, and follows a predictable succession through different stages of valley filling. Complete valley filling promoted avulsion and the large-scale relocation of valley axes before the next sea-level fall, such that successive 100 kyr valley fills show a distributary pattern. Basic elements within coastal plain valleys can be correlated with the record offshore, where cross-shelf valleys have been described from seismic data. Falling stage to lowstand channelbelts

  17. The response of the Okhotsk Sea environment to the orbital-millennium global climate changes during the Last Glacial Maximum, deglaciation and Holocene

    NASA Astrophysics Data System (ADS)

    Gorbarenko, Sergey A.; Artemova, Antonina V.; Goldberg, Evgeniy L.; Vasilenko, Yuriy P.

    2014-05-01

    Reconstruction of regional climate and the Okhotsk Sea (OS) environment for the Last Glacial Maximum (LGM), deglaciation and Holocene was performed on the basis of high-resolution records of ice rafted debris (IRD), СаСО3, opal, total organic carbon (TOС), biogenic Ba (Ba_bio) and redox sensitive element (Mn, Mo) content, and diatom and pollen results of four cores that form a north-southern transect. Age models of the studied cores were earlier established by AMS 14C data, oxygen-isotope chronostratigraphy and tephrochronology. According to received results, since 25 ka the regional climate and OS environmental conditions have changed synchronously with LGM condition, cold Heinrich event 1, Bølling-Allerød (BA) warming, Younger Dryas (YD) cooling and Pre-Boreal (PB) warming recorded in the Greenland ice core, North Atlantic sediment, and China cave stalagmites. Calculation of IRD MAR in sediment of north-south transect cores indicates an increase of sea ice formation several times in the glacial OS as compared to the Late Holocene. Accompanying ice formation, increased brine rejection and the larger potential density of surface water at the north shelf due to a drop of glacial East Asia summer monsoon precipitation and Amur River run off, led to strong enhancement of the role of the OS in glacial North Pacific Intermediate Water (NPIW) formation. The remarkable increase in OS productivity during BA and PB warming was probably related with significant reorganisation of the North Pacific deep water ventilation and nutrient input into the NPIW and OS Intermediate Water (OSIW). Seven Holocene OS millennial cold events based on the elevated values of the detrended IRD stack record over the IRD broad trend in the sediments of the studied cores have occurred synchronously with cold events recorded in the North Atlantic, Greenland ice cores and China cave stalagmites after 9 ka. Diatom production in the OS was mostly controlled by sea ice cover changes and surface

  18. Influence of changes in climate, sea level, and depositional systems on the fossil record of the Neoproterozoic-early Cambrian metazoan radiation, Australia

    SciTech Connect

    Mount, J.F.; McDonald, C. )

    1992-11-01

    On the Australian continent the fossil record of the initial appearance and radiation of higher metazoans is strongly influenced by the distribution of facies suitable for fossil preservation. The limited stratigraphic range of the [open quotes]Ediacaran[close quotes] fauna, the seemingly abrupt appearance and radiation of Cambrian-aspect traces, and the apparently late appearance of skeletogenous organisms are all functions of the spatial and temporal distributions of key habitats. The principal controls on the formation of these habitats appear to have been changes in climate and siliciclastic sediment supply coupled with cyclic changes in sea level. Aspects of the artifactual bias documented in Australia are recognized (but rarely documented) in Precambrian-Cambrian boundary sections worldwide. This bias may ultimately form a major stumbling block to detailed reconstruction of early metazoan evolution. 43 refs., 3 figs.

  19. Global climatic change

    SciTech Connect

    Houghton, R.A.; Woodwell, G.M.

    1989-04-01

    This paper reviews the climatic effects of trace gases such as carbon dioxide and methane. It discusses the expected changes from the increases in trace gases and the extent to which the expected changes can be found in the climate record and in the retreat of glaciers. The use of ice cores in correlating atmospheric composition and climate is discussed. The response of terrestrial ecosystems as a biotic feedback is discussed. Possible responses are discussed, including reduction in fossil-fuel use, controls on deforestation, and reforestation. International aspects, such as the implications for developing nations, are addressed.

  20. Eastern tropical Pacific vegetation response to rapid climate change and sea level rise: A new pollen record from the Gulf of Tehuantepec, southern Mexico

    NASA Astrophysics Data System (ADS)

    Hendy, I. L.; Minckley, T. A.; Whitlock, C.

    2016-08-01

    A 30,000-year-long pollen record from the Gulf of Tehuantepec, southern Mexico shows the varying influence of air temperature, precipitation and eustatic sea-level rise on changes in coastal and upland vegetation patterns. During the late-glacial period, pine-juniper forests grew in the Sierra Madre del Sur along the Pacific Slope with broadleaf forests present at low elevations. Coastal wetland and riparian vegetation were limited in distribution. Significant cooling associated with Heinrich 1 (17,000-15,000 cal yr BP) resulted in an expansion of pine-juniper woodland. By the time of Bølling-Allerød warming (14,700-13,000 cal yr BP), extensive mangrove forest development was assisted by sea-level rise and reduced precipitation associated with a more southerly position of the Intertropical Convergence Zone (ITCZ) than at present. Concurrently, the expansion of oak into pine woodlands was promoted by warmer conditions than before. Increased summer precipitation in the early Holocene and stabilizing sea levels limited mangrove forests along the coast and allowed mixed conifer and hardwood forest to become more widespread inland. The onset of a more seasonal climate, driven by a weakening of the Mexican monsoon and a southerly shift in ITCZ position led to the establishment of modern open forests of pine and oak after 4300 cal yr BP.

  1. Observed climate change hotspots

    NASA Astrophysics Data System (ADS)

    Turco, M.; Palazzi, E.; Hardenberg, J.; Provenzale, A.

    2015-05-01

    We quantify climate change hotspots from observations, taking into account the differences in precipitation and temperature statistics (mean, variability, and extremes) between 1981-2010 and 1951-1980. Areas in the Amazon, the Sahel, tropical West Africa, Indonesia, and central eastern Asia emerge as primary observed hotspots. The main contributing factors are the global increase in mean temperatures, the intensification of extreme hot-season occurrence in low-latitude regions and the decrease of precipitation over central Africa. Temperature and precipitation variability have been substantially stable over the past decades, with only a few areas showing significant changes against the background climate variability. The regions identified from the observations are remarkably similar to those defined from projections of global climate models under a "business-as-usual" scenario, indicating that climate change hotspots are robust and persistent over time. These results provide a useful background to develop global policy decisions on adaptation and mitigation priorities over near-time horizons.

  2. Western water and climate change.

    PubMed

    Dettinger, Michael; Udall, Bradley; Georgakakos, Aris

    2015-12-01

    and agricultural demands. Finally, California's Bay-Delta system is a remarkably localized and severe weakness at the heart of the region's trillion-dollar economy. It is threatened by the full range of potential climate-change impacts expected across the West, along with major vulnerabilities to increased flooding and rising sea levels. PMID:26910940

  3. Western water and climate change.

    PubMed

    Dettinger, Michael; Udall, Bradley; Georgakakos, Aris

    2015-12-01

    and agricultural demands. Finally, California's Bay-Delta system is a remarkably localized and severe weakness at the heart of the region's trillion-dollar economy. It is threatened by the full range of potential climate-change impacts expected across the West, along with major vulnerabilities to increased flooding and rising sea levels.

  4. A 7000 C-14 Year Record of Environmental Change From North Central Cuba: Implications for Regional Sea Level and Climate Change

    NASA Astrophysics Data System (ADS)

    Peros, M. C.

    2004-12-01

    Paleoenvironmental records from the Caribbean are rare. To fill in this gap, a study of Laguna de la Leche, a 67 square kilometer coastal lake located in north central Cuba, was undertaken. Sediment cores were extracted from this lake and its vicinity in order to study to the Holocene sea level and climate history of the area. The cores were studied using pollen, benthic foraminifera, and stable isotopes of oxygen and carbon. A chronology was established by radiocarbon dating. The results show that from approximately 7000 C-14 years to 5000 C-14 years B.P., Laguna de la Leche was a marsh dominated by cattail (Typha domingensis). From 5000 C-14 years to the present, water level rose, turning the marsh in to a shallow, saline lake. Beginning around 1700 C-14 years B.P., mangroves expanded across the area, and are presently prograding into Laguna de la Leche. It is anticipated that over the next several hundred years, Laguna de la Leche may be completely infilled by mangroves. The cause of the rise in lake level appears to have been driven mostly by relative sea level rise. Pollen records from Florida and southern Alabama show an abrupt transition from oak-grassland to pine dominated systems at roughly 5000 C-14 years B.P. This shift from dryer to wetter conditions has been interpreted as representing an increase in the water table due to regional sea level rise (Watts and Hansen, 1994), and is coincident with the marsh-lake transition at Laguna de la Leche. The possibility that an increase in precipitation occurred at 5000 C-14 years B.P. is still being studied, but an oxygen isotope record from Haiti (Hodell et al., 1991) provides no evidence for such a climatic shift.

  5. Climate Change, Sea-Level Rise and Implications for Coastal and Estuarine Shoreline Management with Particular Reference to the Ecology of Intertidal Benthic Macrofauna in NW Europe

    PubMed Central

    Fujii, Toyonobu

    2012-01-01

    In many European estuaries, extensive areas of intertidal habitats consist of bare mudflats and sandflats that harbour a very high abundance and biomass of macrobenthic invertebrates. The high stocks of macrobenthos in turn provide important food sources for the higher trophic levels such as fish and shorebirds. Climate change and associated sea-level rise will have potential to cause changes in coastal and estuarine physical properties in a number of ways and thereby influence the ecology of estuarine dependent organisms. Although the mechanisms involved in biological responses resulting from such environmental changes are complex, the ecological effects are likely to be significant for the estuarine benthic macrofauna and hence the consumers they support. This paper reviews the utilisation patterns of estuarine intertidal habitats by shorebirds, fish and crustaceans, as well as factors affecting the distribution, abundance and biomass of estuarine macrobenthos that is known to be important food source for these estuarine predators. This study also provides simple conceptual models of the likely impacts of sea-level rise on the physical and biological elements of estuarine intertidal habitats, and implications of these results are discussed in the context of sustainable long term flood and coastal management in estuarine environments. PMID:24832510

  6. Climate Change, Sea-Level Rise and Implications for Coastal and Estuarine Shoreline Management with Particular Reference to the Ecology of Intertidal Benthic Macrofauna in NW Europe.

    PubMed

    Fujii, Toyonobu

    2012-11-05

    In many European estuaries, extensive areas of intertidal habitats consist of bare mudflats and sandflats that harbour a very high abundance and biomass of macrobenthic invertebrates. The high stocks of macrobenthos in turn provide important food sources for the higher trophic levels such as fish and shorebirds. Climate change and associated sea-level rise will have potential to cause changes in coastal and estuarine physical properties in a number of ways and thereby influence the ecology of estuarine dependent organisms. Although the mechanisms involved in biological responses resulting from such environmental changes are complex, the ecological effects are likely to be significant for the estuarine benthic macrofauna and hence the consumers they support. This paper reviews the utilisation patterns of estuarine intertidal habitats by shorebirds, fish and crustaceans, as well as factors affecting the distribution, abundance and biomass of estuarine macrobenthos that is known to be important food source for these estuarine predators. This study also provides simple conceptual models of the likely impacts of sea-level rise on the physical and biological elements of estuarine intertidal habitats, and implications of these results are discussed in the context of sustainable long term flood and coastal management in estuarine environments.

  7. Ocean circulation and climate change

    NASA Astrophysics Data System (ADS)

    Hasselmann, Klaus

    1991-09-01

    Recent numerical simulations using global ocean circulation models are reviewed together with model experiments involving further important climate sub-systems with which the ocean interacts: the atmosphere, the air-sea interface and the global carbon cycle. A common feature of all ocean circulation experiments considered is the strong sensitivity of the circulation to relatively minor changes in surface forcing, particularly to the buoyancy fluxes in regions of deep water formation in high latitudes. This may explain some of the well-known deficiencies of past global ocean circulation simulations. The strong sensitivity may also have been the cause of rapid climate changes observed in paleoclimatic records and can lead further to significant natural climate variability on the time scales of a few hundred years through the stochastic forcing of the ocean by atmospheric weather variability. Gobal warming computations using two different coupled ocean-atmosphere models for the "business-as-usual" scenario of the Intergovernmental Panel on Climate Change yield a significantly stronger warming delay due to the heat uptake by the oceans in the Southern Ocean than estimated on the basis of box-diffusion models. Recent advances in surface wave modelling, illustrated by a comparison of wave height fields derived from the WAM model and the GEOSAT altimeter, hold promise for the development of an improved representation of ocean-atmosphere coupling based on an explicit description of the dynamical processes at the air-sea interface. Global carbon cycle simulations with a three dimensional carbon cycle model tuned to reproduce past variations of carbon cycle indices show a significant impact of variations in the ocean circulation on the CO2 concentration in the atmosphere and thereby on climate. The series of experiments suggest that for the study of climate in the time scale range from 10-Ocean circulation and climate change

    NASA Astrophysics Data System (ADS)

    Hasselmann, Klaus

    1991-08-01

    Recent numerical simulations using global ocean circulation models are reviewed together with model experiments involving further important climate sub-systems with which the ocean interacts: the atmosphere, the air-sea interface and the global carbon cycle. A common feature of all ocean circulation experiments considered is the strong sensitivity of the circulation to relatively minor changes in surface forcing, particularly to the buoyancy fluxes in regions of deep water formation in high latitudes. This may explain some of the well-known deficiencies of past global ocean circulation simulations. The strong sensitivity may also have been the cause of rapid climate changes observed in paleoclimatic records and can lead further to significant natural climate variability on the time scales of a few hundred years through the stochastic forcing of the ocean by atmospheric weather variability. Gobal warming computations using two different coupled ocean-atmosphere models for the "business-as-usual" scenario of the Intergovernmental Panel on Climate Change yield a significantly stronger warming delay due to the heat uptake by the oceans in the Southern Ocean than estimated on the basis of box-diffusion models. Recent advances in surface wave modelling, illustrated by a comparison of wave height fields derived from the WAM model and the GEOSAT altimeter, hold promise for the development of an improved representation of ocean-atmosphere coupling based on an explicit description of the dynamical processes at the air-sea interface. Global carbon cycle simulations with a three dimensional carbon cycle model tuned to reproduce past variations of carbon cycle indices show a significant impact of variations in the ocean circulation on the CO2 concentration in the atmosphere and thereby on climate. The series of experiments suggest that for the study of climate in the time scale range from 10-Western water and climate change

    USGS Publications Warehouse

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

    2015-01-01

    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 and agricultural demands. Finally, California's Bay-Delta system is a remarkably localized and severe weakness at the heart of the region's trillion-dollar economy. It is threatened by the full range of potential climate-change impacts expected across the West, along with major vulnerabilities to increased flooding and rising sea levels.

  8. Climate Change and Respiratory Infections.

    PubMed

    Mirsaeidi, Mehdi; Motahari, Hooman; Taghizadeh Khamesi, Mojdeh; Sharifi, Arash; Campos, Michael; Schraufnagel, Dean E

    2016-08-01

    The rate of global warming has accelerated over the past 50 years. Increasing surface temperature is melting glaciers and raising the sea level. More flooding, droughts, hurricanes, and heat waves are being reported. Accelerated changes in climate are already affecting human health, in part by altering the epidemiology of climate-sensitive pathogens. In particular, climate change may alter the incidence and severity of respiratory infections by affecting vectors and host immune responses. Certain respiratory infections, such as avian influenza and coccidioidomycosis, are occurring in locations previously unaffected, apparently because of global warming. Young children and older adults appear to be particularly vulnerable to rapid fluctuations in ambient temperature. For example, an increase in the incidence in childhood pneumonia in Australia has been associated with sharp temperature drops from one day to the next. Extreme weather events, such as heat waves, floods, major storms, drought, and wildfires, are also believed to change the incidence of respiratory infections. An outbreak of aspergillosis among Japanese survivors of the 2011 tsunami is one such well-documented example. Changes in temperature, precipitation, relative humidity, and air pollution influence viral activity and transmission. For example, in early 2000, an outbreak of Hantavirus respiratory disease was linked to a local increase in the rodent population, which in turn was attributed to a two- to threefold increase in rainfall before the outbreak. Climate-sensitive respiratory pathogens present challenges to respiratory health that may be far greater in the foreseeable future. PMID:27300144

  9. Climate Change and Respiratory Infections.

    PubMed

    Mirsaeidi, Mehdi; Motahari, Hooman; Taghizadeh Khamesi, Mojdeh; Sharifi, Arash; Campos, Michael; Schraufnagel, Dean E

    2016-08-01

    The rate of global warming has accelerated over the past 50 years. Increasing surface temperature is melting glaciers and raising the sea level. More flooding, droughts, hurricanes, and heat waves are being reported. Accelerated changes in climate are already affecting human health, in part by altering the epidemiology of climate-sensitive pathogens. In particular, climate change may alter the incidence and severity of respiratory infections by affecting vectors and host immune responses. Certain respiratory infections, such as avian influenza and coccidioidomycosis, are occurring in locations previously unaffected, apparently because of global warming. Young children and older adults appear to be particularly vulnerable to rapid fluctuations in ambient temperature. For example, an increase in the incidence in childhood pneumonia in Australia has been associated with sharp temperature drops from one day to the next. Extreme weather events, such as heat waves, floods, major storms, drought, and wildfires, are also believed to change the incidence of respiratory infections. An outbreak of aspergillosis among Japanese survivors of the 2011 tsunami is one such well-documented example. Changes in temperature, precipitation, relative humidity, and air pollution influence viral activity and transmission. For example, in early 2000, an outbreak of Hantavirus respiratory disease was linked to a local increase in the rodent population, which in turn was attributed to a two- to threefold increase in rainfall before the outbreak. Climate-sensitive respiratory pathogens present challenges to respiratory health that may be far greater in the foreseeable future.

  10. Sea level change: a philosophical approach

    NASA Astrophysics Data System (ADS)

    Leinfelder, R.; Seyfried, H.

    1993-07-01

    The present Cenozoic era is an ‘icehouse’ episode characterized by a low sea level. Since the beginning of the industrial revolution, the human race has been emitting greenhouse gases, increasing the global atmospheric temperature, and causing a rise in sea level. If emissions continue to increase at the present rate, average global temperatures may rise by 1.5°C by the year 2050, accompanied by a rise of about 30 cm in sea level. However, the prediction of future climatic conditions and sea level is hampered by the difficulty in modelling the interactions between the lithosphere, kryosphere, biosphere and atmosphere; in addition, the buffering capacity of our planet is still poorly understood. As scientists cannot offer unambiguous answers to simple questions, sorcerer's apprentices fill in the gaps, presenting plans to save planet without inconveniencing us. The geological record can help us to learn about the regulation mechanisms of our planet, many of which are connected with or expressed as sea level changes. Global changes in sea level are either tectono-eustatic or glacioeustatic. Plate tectonic processes strongly control sea levels and climate in the long term. There is a strong feed-back mechanism between sea level and climate; both can influence and determine each other. Although high sea levels are a powerful climatic buffer, falling sea levels accelerate climatic accentuation, the growth of the polar ice caps and will hence amplify the drop in sea level. Important sources of fossil greenhouse gases are botanic CO2 production, CO2 released by volcanic activity, and water vapour. The latter is particularly important when the surface area of the sea increases during a rise in sea level (‘maritime greenhouse effect’). A ‘volcanogenic greenhouse effect’ (release of volcanogenic CO2) is possibly not equally important, as intense volcanic activity may take place both during icehouse episodes as well as during greenhouse episodes. The hydrosphere

  11. Physical processes mediating climate impacts in shelf sea ecosystems

    NASA Astrophysics Data System (ADS)

    Holt, Jason; Schrum, Corinna; Cannaby, Heather; Allen, Icarus; Artioli, Yuri; Butenschon, Momme; Daewel, Ute; Fach, Bettina; Pushpadas, Dhanya; Salihoglu, Baris; Wakelin, Sarah

    2013-04-01

    How global scale climate change might impact coastal and shelf seas is far from straightforward. A myriad of physical processes can potentially act as vectors transferring the larger scale oceanic and atmospheric variability and change to shelf sea physics, biogeochemistry and lower trophic level ecosystems. These act on a wide range of time scales, being strongly dependent on the prevailing conditions of an individual shelf sea basin. Examples of the physical processes include upper ocean warming, seasonal/permanent stratification, wind mixing, convective mixing, light climate, terrestrial input, circulation and ocean-shelf exchange. These potentially impact ecosystem processes such as primary production, plankton community structured, bloom timing, and mid-water production. However, different processes often act in a different sense and are not necessarily additive, leading to damping or amplification effects. During the MEECE project (www.meece.eu) we conducted a series of coordinated downscaled coupled physics-ecosystem model experiments to explore these issues. Here, we review the prevailing physical processes, contrasting five very different shelf sea regions: North Sea, Celtic seas, Baltic Sea, Black sea and Barents Sea, using results from three different model systems: POLCOMS-ERSEM, ECOSMO, BIMS-ECO. Using this ensemble of simulations, along with process sensitivity studies and multiple forcing studies, we are able to identify which physical processes are important in which region, and how they interact. This builds up a picture of contrasting vulnerability of these regions to different vectors of change.

  12. Managing Climate Change Refugia for Climate Adaptation

    PubMed Central

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

    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 enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change. PMID:27509088

  13. Managing Climate Change Refugia for Climate Adaptation.

    PubMed

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

    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 enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change. PMID:27509088

  14. Managing Climate Change Refugia for Climate Adaptation.

    PubMed

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

    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 enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change.

  15. Long-term effects of climate change on the hydrological system of a lowland area at the German North Sea coast

    NASA Astrophysics Data System (ADS)

    Graeff, Thomas; Baroni, Gabriele; Krause, Stefan

    2014-05-01

    Coastal areas are highly vulnerable to the impacts of climate change. In particular for the winter season, global sea level rise is expected to be combined with increased precipitation and higher storm surge frequency. During summer, due to the increase of temperature, enhanced evapotranspiration with an increase of groundwater intrusion has been observed. It is expected that the salinization of the surface will rise under drier conditions by upward seeping groundwater. Coastal water resource management requires a better understanding and predictions of these dynamic systems. Therefore, a long-term monitoring programme has been established at the German North Sea coast, located at the estuary of the River Ems. The research area is dominated by a dense canal system that is regulated by pumping stations and tidal gates. Landuse of the area is mainly dairy farming with 30 % of the area below sea level. The underlying aquifer is confined and brackish, and it is connected to the surface water by geological faults of old paleo-channels. Observations in those areas indicate a high salinity with concentrations peaking during the summer period. This study investigates the effects of climate change on water balance and salt transport by applying regional climate models (RCMs) based on the IPCC emission scenarios for the period until 2100 as drivers for a hydrological and solute transport model. To investigate the impact of different meteorological scenarios, the RCM results for the climate scenarios A1B, A2 and B1 are used to cover an increase of future temperature between 1 and 3.5 K. As changes in water level and salinity are expected to influence vegetation patterns (and water management aims to guaranty agricultural use) two alternative landuse scenarios are considered. The first scenario assumes that the technological level of the management will be adapted to rainfall and sea level but without additional drainage from the hinterland to reduce salt water concentration

  16. Changes in North Atlantic deep-sea temperature during climatic fluctuations of the last 25,000 years based on ostracode Mg/Ca ratios

    USGS Publications Warehouse

    Dwyer, Gary S.; Cronin, Thomas M.; Baker, Paul A.; Rodriguez-Lazaro, Julio

    2000-01-01

    We reconstructed three time series of last glacial-to-present deep-sea temperature from deep and intermediate water sediment cores from the western North Atlantic using Mg/Ca ratios of benthic ostracode shells. Although the Mg/Ca data show considerable variability (“scatter”) that is common to single-shell chemical analyses, comparisons between cores, between core top shells and modern bottom water temperatures (BWT), and comparison to other paleo-BWT proxies, among other factors, suggest that multiple-shell average Mg/Ca ratios provide reliable estimates of BWT history at these sites. The BWT records show not only glacial-to-interglacial variations but also indicate BWT changes during the deglacial and within the Holocene interglacial stage. At the deeper sites (4500- and 3400-m water depth), BWT decreased during the last glacial maximum (LGM), the late Holocene, and possibly during the Younger Dryas. Maximum deep-sea warming occurred during the latest deglacial and early Holocene, when BWT exceeded modern values by as much as 2.5°C. This warming was apparently most intense around 3000 m, the depth of the modern-day core of North Atlantic deep water (NADW). The BWT variations at the deeper water sites are consistent with changes in thermohaline circulation: warmer BWT signifies enhanced NADW influence relative to Antarctic bottom water (AABW). Thus maximum NADW production and associated heat flux likely occurred during the early Holocene and decreased abruptly around 6500 years B.P., a finding that is largely consistent with paleonutrient studies in the deep North Atlantic. BWT changes in intermediate waters (1000-m water depth) of the subtropical gyre roughly parallel the deep BWT variations including dramatic mid-Holocene cooling of around 4°C. Joint consideration of the Mg/Ca-based BWT estimates and benthic oxygen isotopes suggests that the cooling was accompanied by a decrease in salinity at this site. Subsequently, intermediate waters warmed to modern

  17. Linking sandeel consumption and the likelihood of starvation in harbour porpoises in the Scottish North Sea: could climate change mean more starving porpoises?

    PubMed

    MacLeod, Colin D; Santos, M Begoña; Reid, Robert J; Scott, Beth E; Pierce, Graham J

    2007-04-22

    Sandeels are known to be negatively affected by climate change in a number of ways. This study investigated whether these changes are affecting the harbour porpoise (Phocoena phocoena), a species which consumes sandeels. Porpoise diet was examined in spring (March-May), a critical time of year for survival when sandeels are important prey, from 1993 to 2001 to provide baseline information on the proportion of sandeels consumed. When data from spring 2002 and 2003 were compared to these baseline data, the diet was found to be substantially different, with a significant and substantially smaller proportion of sandeels being consumed in March and May. There were also differences in the number of porpoises starving between the two time periods (33% in spring 2002 and 2003 died of starvation, but only 5% in the baseline period). This suggests that a lower proportion of sandeels in the diet of porpoises in spring increases the likelihood of starvation. Therefore, we suggest that the negative effects of climate change on sandeel availability may have serious negative effects on harbour porpoise populations in the North Sea by increasing the likelihood of starvation in spring.

  18. Poverty and Climate Change

    NASA Astrophysics Data System (ADS)

    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.

  1. Avoiding dangerous climate change

    SciTech Connect

    Hans Joachim Schellnhuber; Wolfgang Cramer; Nebojsa Nakicenovic; Tom Wigley; Gary Yohe

    2006-02-15

    In 2005 the UK Government hosted the Avoiding Dangerous Climate Change conference to take an in-depth look at the scientific issues associated with climate change. This volume presents the most recent findings from the leading international scientists that attended the conference. The topics addressed include critical thresholds and key vulnerabilities of the climate system, impacts on human and natural systems, socioeconomic costs and benefits of emissions pathways, and technological options for meeting different stabilisation levels of greenhouse gases in the atmosphere. Contents are: Foreword from Prime Minister Tony Blair; Introduction from Rajendra Pachauri, Chairman of the IPCC; followed by 41 papers arranged in seven sections entitled: Key Vulnerabilities of the Climate System and Critical Thresholds; General Perspectives on Dangerous Impacts; Key Vulnerabilities for Ecosystems and Biodiversity; Socio-Economic Effects; Regional Perspectives; Emission Pathways; and Technological Options. Four papers have been abstracted separately for the Coal Abstracts database.

  2. Can regional climate engineering save the summer Arctic sea ice?

    NASA Astrophysics Data System (ADS)

    Tilmes, S.; Jahn, Alexandra; Kay, Jennifer E.; Holland, Marika; Lamarque, Jean-Francois

    2014-02-01

    Rapid declines in summer Arctic sea ice extent are projected under high-forcing future climate scenarios. Regional Arctic climate engineering has been suggested as an emergency strategy to save the sea ice. Model simulations of idealized regional dimming experiments compared to a business-as-usual greenhouse gas emission simulation demonstrate the importance of both local and remote feedback mechanisms to the surface energy budget in high latitudes. With increasing artificial reduction in incoming shortwave radiation, the positive surface albedo feedback from Arctic sea ice loss is reduced. However, changes in Arctic clouds and the strongly increasing northward heat transport both counteract the direct dimming effects. A 4 times stronger local reduction in solar radiation compared to a global experiment is required to preserve summer Arctic sea ice area. Even with regional Arctic dimming, a reduction in the strength of the oceanic meridional overturning circulation and a shut down of Labrador Sea deep convection are possible.

  3. Climate impacts of parameterized Nordic Sea overflows

    NASA Astrophysics Data System (ADS)

    Danabasoglu, Gokhan; Large, William G.; Briegleb, Bruce P.

    2010-11-01

    Atlantic. In the uncoupled simulation with the OFP, the warm bias of the control simulation in the deep North Atlantic is substantially reduced along with salinity bias reductions in the northern North Atlantic. There are similar but more modest bias reductions in the deep temperature and salinity distributions especially in the northern North Atlantic in the coupled OFP case. In coupled simulations, there are noticeable impacts of the OFP on climate. The sea surface temperatures (SSTs) are warmer by more than 5°C off the North American coast and by more than 1°C in the Nordic Sea with the OFP. The surface heat fluxes mostly act to diminish these SST changes. There are related changes in the sea level pressure, leading to about 15% weaker westerly wind stress in the northern North Atlantic. In response to the warmer Nordic Sea SSTs, there are reductions in the sea ice extent, improving comparisons with observations. Although the OFP cases improve many aspects of the simulations compared to observations, some significant biases remain, more in coupled than in uncoupled simulations.

  4. Debating Climate Change

    SciTech Connect

    Malone, Elizabeth L.

    2009-11-01

    Debating Climate Change explores, both theoretically and empirically, how people argue about climate change and link to each other through various elements in their arguments. As science is a central issue in the debate, the arguments of scientists and the interpretations and responses of non-scientists are important aspects of the analysis. The book first assesses current thinking about the climate change debate and current participants in the debates surrounding the issue, as well as a brief history of various groups’ involvements. Chapters 2 and 3 distill and organize various ways of framing the climate change issue. Beginning in Chapter 4, a modified classical analysis of the elements carried in an argument is used to identify areas and degrees of disagreement and agreement. One hundred documents, drawn from a wide spectrum of sources, map the topic and debate space of the climate change issue. Five elements of each argument are distilled: the authority of the writer, the evidence presented, the formulation of the argument, the worldview presented, and the actions proposed. Then a social network analysis identifies elements of the arguments that point to potential agreements. Finally, the book suggests mechanisms by which participants in the debate can build more general agreements on elements of existing agreement.

  5. Marine viruses and global climate change.

    PubMed

    Danovaro, Roberto; Corinaldesi, Cinzia; Dell'anno, Antonio; Fuhrman, Jed A; Middelburg, Jack J; Noble, Rachel T; Suttle, Curtis A

    2011-11-01

    Sea-surface warming, sea-ice melting and related freshening, changes in circulation and mixing regimes, and ocean acidification induced by the present climate changes are modifying marine ecosystem structure and function and have the potential to alter the cycling of carbon and nutrients in surface oceans. Changing climate has direct and indirect consequences on marine viruses, including cascading effects on biogeochemical cycles, food webs, and the metabolic balance of the ocean. We discuss here a range of case studies of climate change and the potential consequences on virus function, viral assemblages and virus-host interactions. In turn, marine viruses influence directly and indirectly biogeochemical cycles, carbon sequestration capacity of the oceans and the gas exchange between the ocean surface and the atmosphere. We cannot yet predict whether the viruses will exacerbate or attenuate the magnitude of climate changes on marine ecosystems, but we provide evidence that marine viruses interact actively with the present climate change and are a key biotic component that is able to influence the oceans' feedback on climate change. Long-term and wide spatial-scale studies, and improved knowledge of host-virus dynamics in the world's oceans will permit the incorporation of the viral component into future ocean climate models and increase the accuracy of the predictions of the climate change impacts on the function of the oceans.

  6. Climate Change: Good for Us?

    ERIC Educational Resources Information Center

    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)

  7. Impact of change in climate and policy from 1988 to 2007 on environmental and microbial variables at the time series station Boknis Eck, Baltic Sea

    NASA Astrophysics Data System (ADS)

    Hoppe, H.-G.; Giesenhagen, H. C.; Koppe, R.; Hansen, H.-P.; Gocke, K.

    2012-12-01

    Phytoplankton and bacteria are sensitive indicators of environmental change. The temporal development of these key organisms was monitored from 1988 to the end of 2007 at the time series station Boknis Eck in the Western Baltic Sea. This period was characterized by the adaption of the Baltic Sea ecosystem to changes in the environmental conditions caused by the collapse and conversion of the political system in the Southern and Eastern Border States, accompanied by the general effects of global climate change. Measured variables were chlorophyll, primary production, bacteria number, -biomass and -production, glucose turnover rate, macro-nutrients, pH, temperature and salinity. Negative trends with time were recorded for chlorophyll, the bacterial variables, nitrate, ammonia, phosphate, silicate, oxygen and salinity while temperature, pH, and the ratio between bacteria numbers and chlorophyll increased. The strongest reductions with time occurred for the annual maximum values, e.g. for chlorophyll during the spring bloom or for nitrate during winter, while the annual minimum values remained more stable. In deep water above sediment the negative trends of oxygen, nitrate, phosphate and bacterial variables as well as the positive trend of temperature were similar to those in the surface while the trends of salinity, ammonia and silicate were opposite to those in the surface. Decreasing oxygen even in the surface layer was of particular interest because it suggested enhanced recycling of nutrients from the deep hypoxic zones to the surface by vertical mixing. In the long run all variables correlated positively with temperature, except chlorophyll and salinity. Salinity correlated negatively with all bacterial variables as well as precipitation and positively with chlorophyll. Surprisingly, bacterial variables did not correlate with chlorophyll which may be inherent with the time lag between the peaks of phytoplankton and bacteria during spring. Compared to the 20-yr

  8. Impact of change in climate and policy from 1988 to 2007 on environmental and microbial variables at the time series station Boknis Eck, Baltic Sea

    NASA Astrophysics Data System (ADS)

    Hoppe, H.-G.; Giesenhagen, H. C.; Koppe, R.; Hansen, H.-P.; Gocke, K.

    2013-07-01

    Phytoplankton and bacteria are sensitive indicators of environmental change. The temporal development of these key organisms was monitored from 1988 to the end of 2007 at the time series station Boknis Eck in the western Baltic Sea. This period was characterized by the adaption of the Baltic Sea ecosystem to changes in the environmental conditions caused by the conversion of the political system in the southern and eastern border states, accompanied by the general effects of global climate change. Measured variables were chlorophyll, primary production, bacteria number, -biomass and -production, glucose turnover rate, macro-nutrients, pH, temperature and salinity. Negative trends with time were recorded for chlorophyll, bacteria number, bacterial biomass and bacterial production, nitrate, ammonia, phosphate, silicate, oxygen and salinity while temperature, pH, and the ratio between bacteria numbers and chlorophyll increased. Strongest reductions with time occurred for the annual maximum values, e.g. for chlorophyll during the spring bloom or for nitrate during winter, while the annual minimum values remained more stable. In deep water above sediment the negative trends of oxygen, nitrate, phosphate and bacterial variables as well as the positive trend of temperature were similar to those in the surface while the trends of salinity, ammonia and silicate were opposite to those in the surface. Decreasing oxygen, even in the surface layer, was of particular interest because it suggested enhanced recycling of nutrients from the deep hypoxic zones to the surface by vertical mixing. The long-term seasonal patterns of all variables correlated positively with temperature, except chlorophyll and salinity. Salinity correlated negatively with all bacterial variables (as well as precipitation) and positively with chlorophyll. Surprisingly, bacterial variables did not correlate with chlorophyll, which may be inherent with the time lag between the peaks of phytoplankton and

  9. How does climate change influence Arctic mercury?

    PubMed

    Stern, Gary A; Macdonald, Robie W; Outridge, Peter M; Wilson, Simon; Chételat, John; Cole, Amanda; Hintelmann, Holger; Loseto, Lisa L; Steffen, Alexandra; Wang, Feiyue; Zdanowicz, Christian

    2012-01-01

    Recent studies have shown that climate change is already having significant impacts on many aspects of transport pathways, speciation and cycling of mercury within Arctic ecosystems. For example, the extensive loss of sea-ice in the Arctic Ocean and the concurrent shift from greater proportions of perennial to annual types have been shown to promote changes in primary productivity, shift foodweb structures, alter mercury methylation and demethylation rates, and influence mercury distribution and transport across the ocean-sea-ice-atmosphere interface (bottom-up processes). In addition, changes in animal social behavior associated with changing sea-ice regimes can affect dietary exposure to mercury (top-down processes). In this review, we address these and other possible ramifications of climate variability on mercury cycling, processes and exposure by applying recent literature to the following nine questions; 1) What impact has climate change had on Arctic physical characteristics and processes? 2) How do rising temperatures affect atmospheric mercury chemistry? 3) Will a decrease in sea-ice coverage have an impact on the amount of atmospheric mercury deposited to or emitted from the Arctic Ocean, and if so, how? 4) Does climate affect air-surface mercury flux, and riverine mercury fluxes, in Arctic freshwater and terrestrial systems, and if so, how? 5) How does climate change affect mercury methylation/demethylation in different compartments in the Arctic Ocean and freshwater systems? 6) How will climate change alter the structure and dynamics of freshwater food webs, and thereby affect the bioaccumulation of mercury? 7) How will climate change alter the structure and dynamics of marine food webs, and thereby affect the bioaccumulation of marine mercury? 8) What are the likely mercury emissions from melting glaciers and thawing permafrost under climate change scenarios? and 9) What can be learned from current mass balance inventories of mercury in the Arctic? The

  10. The changing seasonal climate in the Arctic

    PubMed Central

    Bintanja, R.; van der Linden, E. C.

    2013-01-01

    Ongoing and projected greenhouse warming clearly manifests itself in the Arctic regions, which warm faster than any other part of the world. One of the key features of amplified Arctic warming concerns Arctic winter warming (AWW), which exceeds summer warming by at least a factor of 4. Here we use observation-driven reanalyses and state-of-the-art climate models in a variety of standardised climate change simulations to show that AWW is strongly linked to winter sea ice retreat through the associated release of surplus ocean heat gained in summer through the ice-albedo feedback (~25%), and to infrared radiation feedbacks (~75%). Arctic summer warming is surprisingly modest, even after summer sea ice has completely disappeared. Quantifying the seasonally varying changes in Arctic temperature and sea ice and the associated feedbacks helps to more accurately quantify the likelihood of Arctic's climate changes, and to assess their impact on local ecosystems and socio-economic activities. PMID:23532038

  11. The changing seasonal climate in the Arctic.

    PubMed

    Bintanja, R; van der Linden, E C

    2013-01-01

    Ongoing and projected greenhouse warming clearly manifests itself in the Arctic regions, which warm faster than any other part of the world. One of the key features of amplified Arctic warming concerns Arctic winter warming (AWW), which exceeds summer warming by at least a factor of 4. Here we use observation-driven reanalyses and state-of-the-art climate models in a variety of standardised climate change simulations to show that AWW is strongly linked to winter sea ice retreat through the associated release of surplus ocean heat gained in summer through the ice-albedo feedback (~25%), and to infrared radiation feedbacks (~75%). Arctic summer warming is surprisingly modest, even after summer sea ice has completely disappeared. Quantifying the seasonally varying changes in Arctic temperature and sea ice and the associated feedbacks helps to more accurately quantify the likelihood of Arctic's climate changes, and to assess their impact on local ecosystems and socio-economic activities.

  12. Climate-change scenarios

    USGS Publications Warehouse

    Wagner, F.H.; Stohlgren, T.J.; Baldwin, C.K.; Mearns, L.O.; Wagner, F.H.

    2003-01-01

    In 1991, the United States Congress passed the Global Change Research Act directing the Executive Branch of government to assess the potential effects of predicted climate change and variability on the nation. This congressional action followed formation of the Intergovernmental Panel on Climate Change (IPCC) in 1988 by the United Nations Environmental Program and World Meteorological Organization. Some 2,000 scientists from more than 150 nations contribute to the efforts of the IPCC. Under coordination of the U.S. Global Change Research Program, the congressionally ordered national assessment has divided the country into 19 regions and five socio-economic sectors that cut across the regions: agriculture, coastal and marine systems, forests, human health, and water. Potential climate-change effects are being assessed in each region and sector, and those efforts collectively make up the national assessment. This document reports the assessment of potential climate-change effects on the Rocky Mountain/Great Basin (RMGB) region which encompasses parts of nine western states. The assessment began February 16-18, 1998 with a workshop in Salt Lake City co-convened by Frederic H. Wagner of Utah State University and Jill Baron of the U.S. Geological Survey Biological Resources Division (BRD). Invitations were sent to some 300 scientists and stakeholders representing 18 socio-economic sectors in nine statesa?|

  13. Anthropogenic climate change

    SciTech Connect

    Budyko, M.I.; Izreal, Yu.A.

    1991-01-01

    The climate modeling community would agree that the present generation of theoretical models cannot adequately answer important question about the climatic implications of increasing concentrations of CO[sub 2] and other greenhouse gases. Society, however, is presently deciding by its action, or inaction, the policies that will deal with the extent and results of our collective flatulence. In this situation, an engineering approach to estimating the developing pattern of anthropogenic climate change is appropriate. For example, Budyko has argued that, while scientists may have made great advances in modelling the flow around an airfoil, engineers make extensive use of empirical equations and measurements to design airplanes that fly. Budyko and Izreal have produced an encyclopedic treatise summarizing the results of Soviet researchers in applying empirical and semiempirical methods to estimating future climatic patterns, and some of their ensuring effects. These techniques consist mainly of statistical relationships derived from 1850-1950 network data and of patterns revealed by analysis of paleoclimatic data. An important part of the Soviet effort in anthropogenic climate-change studies is empirical techniques that represent independent verification of the results of theoretical climate models.

  14. [Lifestyle and climate change].

    PubMed

    Lidegaard, Øjvind

    2009-10-26

    The majority of physicians are aware of the urgency of preventing major global warming, and of the global health consequences such warming could bring. Therefore, we should perhaps be more motivated to mitigate these climate changes. The Danish Medical Association should stress the importance of preventing major global climate health disasters, and the need for ambitious international reduction agreements. In our advice and treatment of patients, focus could be on mutually shared strategies comprising mitigation of global warming and changing of life-style habits to improve our general health.

  15. Antarctic Sea Ice Patterns and Its Relationship with Climate

    NASA Astrophysics Data System (ADS)

    Barreira, S.

    2015-12-01

    Antarctic sea ice concentration fields show a strong seasonal and interannual variation closely tied to changes in climate patterns. The Ross, Amundsen, Bellingshausen, and Weddell Seas during Summer-Autumn and the Southern Ocean regions north of these areas during Winter-Spring have the greatest sea ice variability. Principal components analysis in T- mode, Varimax-rotated applied on Antarctic monthly sea ice concentration anomaly (SICA) fields for 1979-2015 (NASA Team algorithm data sets available at nsidc.org) revealed the main spatial characteristics of Antarctic sea ice patterns and their relationship with atmospheric circulation. This analysis yielded five patterns of sea ice for winter-spring and three patterns for summer-autumn, each of which has a positive and negative phase. To understand the links between the SICA patterns and climate, we extracted the mean pressure and temperature fields for the months with high loadings (positive or negative) of the sea ice patterns. The first pattern of winter-spring sea ice concentration is a dipole structure between the Drake Passage and northern regions of the Bellingshausen and Weddell Seas and, the South Atlantic Ocean. The negative phase shows a strong negative SICA over the Atlantic basin. This pattern can be associated with to the atmospheric structures related to a positive SAM index and a wave-3 arrangement around the continent. That is, a strong negative pressure anomaly centered over the Bellingshausen Sea accompanied by three positive pressure anomalies in middle-latitudes. For summer-autumn, the first pattern shows two strong positive SICA areas, in the eastern Weddell Sea and the northwestern Ross Sea. A negative SICA covers the Amundsen-Bellingshausen Seas and northwest of the Antarctic Peninsula. This pattern, frequently seen in summers since 2008, is associated with cool conditions over the Weddell Sea but warmer temperatures and high surface air pressure west, north and northwest of the Peninsula.

  16. Climate change and amphibians

    USGS Publications Warehouse

    Corn, P.S.

    2005-01-01

    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

  17. Climate change, climate variability and brucellosis.

    PubMed

    Rodríguez-Morales, Alfonso J

    2013-04-01

    In addition to natural climate variability observed over comparable time periods, climate change is attributed directly or indirectly to human activity, altering the composition of global atmosphere. This phenomenon continues to be a significant and global threat for the humankind, and its impact compromises many aspects of the society at different levels, including health. The impact of climate change on zoonotic diseases has been largely ignored, particularly brucellosis. We here review some direct and indirect evidences of the impact of climate change and climate variability on brucellosis.

  18. Climate change, pink salmon, and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea

    PubMed Central

    Springer, Alan M.; van Vliet, Gus B.

    2014-01-01

    Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem. PMID:24706809

  19. Climate change, pink salmon, and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea.

    PubMed

    Springer, Alan M; van Vliet, Gus B

    2014-05-01

    Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem.

  20. Climate for Change

    NASA Astrophysics Data System (ADS)

    Newell, Peter

    2000-09-01

    This volume provides a challenging explanation of the forces that have shaped the international global warming debate. It takes a novel approach to the subject by concentrating on the ways non-state actors--such as scientific, environmental and industry groups, as opposed to governmental organizations--affect political outcomes in global fora on climate change. It also provides insights into the role of the media in influencing the agenda. The book draws on a range of analytical approaches to assess and explain the influence of these nongovernmental organizations on the course of global climate politics. The book will be of interest to all researchers and policy makers associated with climate change, and will be used in university courses in international relations, politics, and environmental studies.

  1. Modeling Runoff and Sediments Yields and their Response to Climate Change: Case Study from the Red Sea Coast of Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Alharbi, T.; Sultan, M.; Ahmed, M.; Sefry, S.; AboAbdallah, M.

    2013-12-01

    Efforts to quantify runoff and sediments yields and to assess the factors controlling their spatial and temporal distribution are often hindered by the paucity of appropriate field data. In this study, we developed and applied an integrated cost-effective approach that takes advantages of the readily available remote sensing datasets to quantify the runoff and sediments yields of the Red Sea costal watersheds, Saudi Arabia. The Soil Water Assessment Tool (SWAT) model was implemented to determine annual runoff and sediment yields, spatially delineate the factors controlling their distribution, and predict their response to climate change. SWAT is a public-domain, Geographic Information System (GIS)-based, spatially-distributed, dynamic model that can simulate watershed scale hydrology and water quality processes. The landuse-landcover GIS layer for the selected watersheds was downloaded and manually updated from the Global Land Cover 2000 (GLC 2000) datasets. Soil data was downloaded from the Harmonized World Soil Database (HWSD) and refined from 1:250,000 scale geologic maps. A 90m digital elevation model (DEM) extracted from Shuttle Radar Topography Mission (STRM) data was used to characterize the watershed boundaries in SWAT. Weather data for model simulations was downloaded from the global weather data for SWAT. Model simulations were performed for the period from 1979 to 2010 for 10 watersheds ranging in areas from 5×103 km2 to 107×103 km2. Preliminary results show an average annual precipitation, runoff, and sediments yields of 78.1 mm (8.3 ×109 m3), 24.5 mm (2.6 ×109 m3), 0.1 ton/ha, respectively for Wadi El Hamd watershed (area: 107×103 km2). Model calibration is being performed by comparing simulated stream flow discharge and sediment yields against measured values. The response of the runoff and sediments yields to the climate change is being estimated using predictions from Community Climate System Model (CCSM) outputs.

  2. Climate change velocity underestimates climate change exposure in mountainous regions.

    PubMed

    Dobrowski, Solomon Z; Parks, Sean A

    2016-01-01

    Climate change velocity is a vector depiction of the rate of climate displacement used for assessing climate change impacts. Interpreting velocity requires an assumption that climate trajectory length is proportional to climate change exposure; longer paths suggest greater exposure. However, distance is an imperfect measure of exposure because it does not quantify the extent to which trajectories traverse areas of dissimilar climate. Here we calculate velocity and minimum cumulative exposure (MCE) in degrees Celsius along climate trajectories for North America. We find that velocity is weakly related to MCE; each metric identifies contrasting areas of vulnerability to climate change. Notably, velocity underestimates exposure in mountainous regions where climate trajectories traverse dissimilar climates, resulting in high MCE. In contrast, in flat regions velocity is high where MCE is low, as these areas have negligible climatic resistance to movement. Our results suggest that mountainous regions are more climatically isolated than previously reported. PMID:27476545

  3. Climate change velocity underestimates climate change exposure in mountainous regions

    NASA Astrophysics Data System (ADS)

    Dobrowski, Solomon Z.; Parks, Sean A.

    2016-08-01

    Climate change velocity is a vector depiction of the rate of climate displacement used for assessing climate change impacts. Interpreting velocity requires an assumption that climate trajectory length is proportional to climate change exposure; longer paths suggest greater exposure. However, distance is an imperfect measure of exposure because it does not quantify the extent to which trajectories traverse areas of dissimilar climate. Here we calculate velocity and minimum cumulative exposure (MCE) in degrees Celsius along climate trajectories for North America. We find that velocity is weakly related to MCE; each metric identifies contrasting areas of vulnerability to climate change. Notably, velocity underestimates exposure in mountainous regions where climate trajectories traverse dissimilar climates, resulting in high MCE. In contrast, in flat regions velocity is high where MCE is low, as these areas have negligible climatic resistance to movement. Our results suggest that mountainous regions are more climatically isolated than previously reported.

  4. Climate change velocity underestimates climate change exposure in mountainous regions

    PubMed Central

    Dobrowski, Solomon Z.; Parks, Sean A.

    2016-01-01

    Climate change velocity is a vector depiction of the rate of climate displacement used for assessing climate change impacts. Interpreting velocity requires an assumption that climate trajectory length is proportional to climate change exposure; longer paths suggest greater exposure. However, distance is an imperfect measure of exposure because it does not quantify the extent to which trajectories traverse areas of dissimilar climate. Here we calculate velocity and minimum cumulative exposure (MCE) in degrees Celsius along climate trajectories for North America. We find that velocity is weakly related to MCE; each metric identifies contrasting areas of vulnerability to climate change. Notably, velocity underestimates exposure in mountainous regions where climate trajectories traverse dissimilar climates, resulting in high MCE. In contrast, in flat regions velocity is high where MCE is low, as these areas have negligible climatic resistance to movement. Our results suggest that mountainous regions are more climatically isolated than previously reported. PMID:27476545

  5. Climate change velocity underestimates climate change exposure in mountainous regions.

    PubMed

    Dobrowski, Solomon Z; Parks, Sean A

    2016-08-01

    Climate change velocity is a vector depiction of the rate of climate displacement used for assessing climate change impacts. Interpreting velocity requires an assumption that climate trajectory length is proportional to climate change exposure; longer paths suggest greater exposure. However, distance is an imperfect measure of exposure because it does not quantify the extent to which trajectories traverse areas of dissimilar climate. Here we calculate velocity and minimum cumulative exposure (MCE) in degrees Celsius along climate trajectories for North America. We find that velocity is weakly related to MCE; each metric identifies contrasting areas of vulnerability to climate change. Notably, velocity underestimates exposure in mountainous regions where climate trajectories traverse dissimilar climates, resulting in high MCE. In contrast, in flat regions velocity is high where MCE is low, as these areas have negligible climatic resistance to movement. Our results suggest that mountainous regions are more climatically isolated than previously reported.

  6. Simulated sea surface temperature and heat fluxes in different climates of the Baltic Sea.

    PubMed

    Döscher, Ralf; Meier, H E Markus

    2004-06-01

    The physical state of the Baltic Sea in possible future climates is approached by numerical model experiments with a regional coupled ocean-atmosphere model driven by different global simulations. Scenarios and recent climate simulations are compared to estimate changes. The sea surface is clearly warmer by 2.9 degrees C in the ensemble mean. The horizontal pattern of average annual mean warming can largely be explained in terms of ice-cover reduction. The transfer of heat from the atmosphere to the Baltic Sea shows a changed seasonal cycle: a reduced heat loss in fall, increased heat uptake in spring, and reduced heat uptake in summer. The interannual variability of surface temperature is generally increased. This is associated with a smoothed frequency distribution in northern basins. The overall heat budget shows increased solar radiation to the sea surface, which is balanced by changes of the other heat flux components.

  7. Simulated sea surface temperature and heat fluxes in different climates of the Baltic Sea.

    PubMed

    Döscher, Ralf; Meier, H E Markus

    2004-06-01

    The physical state of the Baltic Sea in possible future climates is approached by numerical model experiments with a regional coupled ocean-atmosphere model driven by different global simulations. Scenarios and recent climate simulations are compared to estimate changes. The sea surface is clearly warmer by 2.9 degrees C in the ensemble mean. The horizontal pattern of average annual mean warming can largely be explained in terms of ice-cover reduction. The transfer of heat from the atmosphere to the Baltic Sea shows a changed seasonal cycle: a reduced heat loss in fall, increased heat uptake in spring, and reduced heat uptake in summer. The interannual variability of surface temperature is generally increased. This is associated with a smoothed frequency distribution in northern basins. The overall heat budget shows increased solar radiation to the sea surface, which is balanced by changes of the other heat flux components. PMID:15264603

  8. Confronting Climate Change

    ERIC Educational Resources Information Center

    Roach, Ronald

    2009-01-01

    The Joint Center for Political and Economic Studies, an African-American think tank based in Washington, D.C., convenes a commission to focus on the disparate impact of climate change on minority communities and help involve historically Black institutions in clean energy projects. Launched formally in July 2008, the Commission to Engage…

  9. Climate Change? When? Where?

    ERIC Educational Resources Information Center

    Boon, Helen

    2009-01-01

    Regional Australian students were surveyed to explore their understanding and knowledge of the greenhouse effect, ozone depletion and climate change. Results were compared with a parallel study undertaken in 1991 in a regional UK city. The comparison was conducted to investigate whether more awareness and understanding of these issues is…

  10. Emissions versus climate change

    EPA Science Inventory

    Climate change is likely to offset some of the improvements in air quality expected from reductions in pollutant emissions. A comprehensive analysis of future air quality over North America suggests that, on balance, the air will still be cleaner in coming decades.

  11. Learning Progressions & Climate Change

    ERIC Educational Resources Information Center

    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…

  12. Resolving discrepancies between hydraulic and chemical calibration data for seawater intrusion groundwater flow models by considering climate-driven sea level change.

    SciTech Connect

    J. Chapman; A. Hassan; K. Pohlmann

    2001-10-18

    Groundwater models of seawater intrusion environments can be calibrated using both hydraulic and chemical information. The possible impact of the long-term transient process of sea level change is difficult to identify, but important to accurate simulation of present conditions. The response times of the pressure and chemical fields to major fluctuations in sea level change are investigated

  13. Climate change in Iceland

    NASA Astrophysics Data System (ADS)

    Snorrason, A.; Bjornsson, H.

    2010-12-01

    The sub-polar maritime climate of Iceland is characterized by relatively large inter-decadal variations. Temperature measurements and climate related proxies show that the 19th century was colder and more variable than the 20th century. Iceland experienced rapid warming in the 1920s and relatively mild conditions prevailed until the 1960s, when colder conditions set in. In recent decades Iceland has again experienced significant warming and early this century the temperatures exceeded those attained during the mid 20th century warm period. The recent warming has been accompanied by significant changes in both physical and biological systems. These include glacier retreat, runoff changes and isostatic rebound, increased plant productivity and changes in tree-limits. In the coastal waters the range of fish species is changing reflecting warmer conditions.

  14. Climate change in Iceland

    NASA Astrophysics Data System (ADS)

    Björnsson, H.; Jónsson, T.

    2009-04-01

    The sub-polar maritime climate of Iceland is characterized by relatively large inter-decadal variations. Temperature measurements and climate related proxies show that the 19th century was colder and more variable than the 20th century. Iceland experienced rapid warming in the 1920s and relatively mild conditions prevailed until the 1960s, when colder conditions set in. In recent decades Iceland has again experienced significant warming and early this century the temperatures exceeded those attained during the mid 20th century warm period. The recent warming has been accompanied by significant changes in both physical and biological systems. These include glacier retreat, runoff and coastal changes, increased plant productivity and changes in tree-limits. In the coastal waters the range of fish species is changing reflecting warmer conditions.

  15. USDA Southwest climate hub for climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA Southwest (SW) Climate Hub was created in February 2014 to develop risk adaptation and mitigation strategies for coping with climate change effects on agricultural productivity. There are seven regional hubs across the country with three subsidiary hubs. The SW Climate Hub Region is made up...

  16. Past and Current Climate Change

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  18. Climate as a driver of evolutionary change.

    PubMed

    Erwin, Douglas H

    2009-07-28

    The link between biodiversity and climate has been obvious to biologists since the work of von Humboldt in the early 1800s, but establishing the relationship of climate to ecological and evolutionary patterns is more difficult. On evolutionary timescales, climate can affect supply of energy by biotic and abiotic effects. Some of the best evidence for a link between biodiversity and climate comes from latitudinal gradients in diversity, which provide an avenue to explore the more general relationship between climate and evolution. Among the wide range of biotic hypotheses, those with the greatest empirical support indicate that warmer climates have provided the energetic foundation for increased biodiversity by fostering greater population size and thus increased extinction resistance; have increased metabolic scope; have allowed more species to exploit specialized niches as a result of greater available energy; and generated faster speciation and/or lower extinction rates. In combination with geologic evidence for carbon dioxide levels and changing areas of tropical seas, these observations provide the basis for a simple, first-order model of the relationship between climate through the Phanerozoic and evolutionary patterns and diversity. Such a model suggests that we should expect greatest marine diversity during globally warm intervals with dispersed continents, broad shelves and moderately extensive continental seas. Demonstrating a significant evolutionary response to either climate or climatic change is challenging, however, because of continuing uncertainties over patterns of Phanerozoic marine diversity and the variety of factors beyond climate that influence evolution. PMID:19640496

  19. Climate as a driver of evolutionary change.

    PubMed

    Erwin, Douglas H

    2009-07-28

    The link between biodiversity and climate has been obvious to biologists since the work of von Humboldt in the early 1800s, but establishing the relationship of climate to ecological and evolutionary patterns is more difficult. On evolutionary timescales, climate can affect supply of energy by biotic and abiotic effects. Some of the best evidence for a link between biodiversity and climate comes from latitudinal gradients in diversity, which provide an avenue to explore the more general relationship between climate and evolution. Among the wide range of biotic hypotheses, those with the greatest empirical support indicate that warmer climates have provided the energetic foundation for increased biodiversity by fostering greater population size and thus increased extinction resistance; have increased metabolic scope; have allowed more species to exploit specialized niches as a result of greater available energy; and generated faster speciation and/or lower extinction rates. In combination with geologic evidence for carbon dioxide levels and changing areas of tropical seas, these observations provide the basis for a simple, first-order model of the relationship between climate through the Phanerozoic and evolutionary patterns and diversity. Such a model suggests that we should expect greatest marine diversity during globally warm intervals with dispersed continents, broad shelves and moderately extensive continental seas. Demonstrating a significant evolutionary response to either climate or climatic change is challenging, however, because of continuing uncertainties over patterns of Phanerozoic marine diversity and the variety of factors beyond climate that influence evolution.

  20. [Effect of climate change on the fisheries conununity pattern in the overwintering ground of open waters of northern East China Sea].

    PubMed

    Liu, Zun-lei; Yuan, Xing-wei; Yang, Lin-lin; Yan, Li-ping; Tian, Yong-jun; Chen, Jia-hua

    2015-03-01

    Data sets of 26 fisheries target species from the fishery-depen-dent and fishery-independent surveys in the overwintering ground of open waters of northern East China Sea (OW-NECS), combined sea surface temperature (SST), were used to examine the links between diversity index, pattern of common variability and climate changes based on the principal component analysis (PCA) and generalized additive model (GAM). The results showed that the shift from a cold regime to a warm regime was detected in SST during the 1970s-2011 with step changes around 1982/ 1983. SST increased during the cold regime and the warm regime before 1998 (warming trend period, 1972-1998), and decreased during the warm regime after 1998 (cooling trend period, 1999-2011). Shannon diversity index was largely dependent on the filefish, which contributed up to 50% of the total production as a single species, with low diversity in the waters of the OW-NECS, during the late 1980s and early 1990s. Excluding the filefish, the diversity index linearly increased and decreased during 1972-1998 and 1999-2011, respectively. The variation pattern generally corresponds with the trend in water temperature, strongly suggesting the effect of the SST on the diversity. The first two components (PC1 and PC2) of PCA for target species, which accounted for 32.43% of the total variance, showed evident decadal variation patterns with a step change during 1992-1999 and inter-annual variability with short-period fluctuation, respectively. It seems that PC1 was associated with large scale climatic change, while PC2 was related to inter-annual oceanographic variability such as ENSO events. Linear fitting results showed winEOF1 had significant effect on PC1, and GAM analysis for PC1 showed that winter EOF1 (winEOF1) and summer EOF2 (sumEOF2) can explain 88.9% of the total variance. Nonlinear effect was also found between PC2 and win EOF1, indicating that the fish community structure, which had predominantly decadal

  1. An objective tropical Atlantic sea surface temperature gradient index for studies of south Amazon dry-season climate variability and change.

    PubMed

    Good, Peter; Lowe, Jason A; Collins, Mat; Moufouma-Okia, Wilfran

    2008-05-27

    Future changes in meridional sea surface temperature (SST) gradients in the tropical Atlantic could influence Amazon dry-season precipitation by shifting the patterns of moisture convergence and vertical motion. Unlike for the El Niño-Southern Oscillation, there are no standard indices for quantifying this gradient. Here we describe a method for identifying the SST gradient that is most closely associated with June-August precipitation over the south Amazon. We use an ensemble of atmospheric general circulation model (AGCM) integrations forced by observed SST from 1949 to 2005. A large number of tropical Atlantic SST gradient indices are generated randomly and temporal correlations are examined between these indices and June-August precipitation averaged over the Amazon Basin south of the equator. The indices correlating most strongly with June-August southern Amazon precipitation form a cluster of near-meridional orientation centred near the equator. The location of the southern component of the gradient is particularly well defined in a region off the Brazilian tropical coast, consistent with known physical mechanisms. The chosen index appears to capture much of the Atlantic SST influence on simulated southern Amazon dry-season precipitation, and is significantly correlated with observed southern Amazon precipitation. We examine the index in 36 different coupled atmosphere-ocean model projections of climate change under a simple compound 1% increase in CO2. Within the large spread of responses, we find a relationship between the projected trend in the index and the Amazon dry-season precipitation trends. Furthermore, the magnitude of the trend relationship is consistent with the inter-annual variability relationship found in the AGCM simulations. This suggests that the index would be of use in quantifying uncertainties in climate change in the region. PMID:18267909

  2. Hantaviruses and climate change.

    PubMed

    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.

  3. Abrupt Impacts of Climate Change: Anticipating Surprises

    NASA Astrophysics Data System (ADS)

    White, James W. C.; Alley, Richard B.; Archer, David E.; Barnosky, Anthony D.; Dunlea, Edward; Foley, Jonathan; Fu, Rong; Holland, Marika M.; Lozier, M. Susan; Schmitt, Johanna; Smith, Laurence C.; Sugihara, George; Thompson, David W. J.; Weaver, Andrew J.; Wofsy, Steven C.

    2014-05-01

    Levels of carbon dioxide and other greenhouse gases in Earth's atmosphere are exceeding levels recorded in the past millions of years, and thus climate is being forced beyond the range of the recent geological era. Lacking concerted action by the world's nations, it is clear that the future climate will be warmer, sea levels will rise, global rainfall patterns will change, and ecosystems will be altered. However, there is still uncertainty about how we will arrive at that future climate state. Although many projections of future climatic conditions have predicted steadily changing conditions giving the impression that communities have time to gradually adapt, the scientific community has been paying increasing attention to the possibility that at least some changes will be abrupt, perhaps crossing a threshold or "tipping point" to change so quickly that there will be little time to react. This presentation will synopsize the new US National Research Council Report, Abrupt Impacts of Climate Change: Anticipating Surprises, highlighting areas of increased and decreased concern, as well as areas of new concern. Emphasis is placed on not only abrupt change in physical climate, but on abrupt changes in human and natural systems that can occur as a result of a slowly changing climate. The report calls for action now on an abrupt change early warning system (ACEWS) if societies are to be resilient to climate change.

  4. Corrigendum to ''Climate-mediated changes in zooplankton community structure for the eastern Bering Sea'' [Deep-Sea Res. II 109 (2014) 157-171

    NASA Astrophysics Data System (ADS)

    Eisner, L. B.; Napp, J. M.; Mier, K. L.; Pinchuk, A. I.; Andrews, A. G.

    2016-10-01

    The authors regret that the panels are mislabelled in the caption for Fig. 7. The caption should read, "Untransformed mean zooplankton abundances in the eastern Bering Sea for large taxa in the (A) north (~60-63°N) and (B) south (<~60°N) and for small taxa in the (C) north and (D) south. Bar indicates warm and cold regimes".

  5. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present.

    PubMed

    Hoff, Ulrike; Rasmussen, Tine L; Stein, Ruediger; Ezat, Mohamed M; Fahl, Kirsten

    2016-01-01

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland-Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean.

  6. Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present

    NASA Astrophysics Data System (ADS)

    Hoff, Ulrike; Rasmussen, Tine L.; Stein, Ruediger; Ezat, Mohamed M.; Fahl, Kirsten

    2016-07-01

    In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species in a record from the southeast Norwegian Sea. We demonstrate that expansion and retreat of sea ice varies consistently in pace with the rapid climate changes 90 kyr ago to present. Sea ice retreats abruptly at the start of warm interstadials, but spreads rapidly during cooling phases of the interstadials and becomes near perennial and perennial during cold stadials and Heinrich events, respectively. Low-salinity surface water and the sea ice edge spreads to the Greenland-Scotland Ridge, and during the largest Heinrich events, probably far into the Atlantic Ocean.

  7. Teaching Climate Change

    NASA Astrophysics Data System (ADS)

    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.

  8. Challenges of climate change: an Arctic perspective.

    PubMed

    Corell, Robert W

    2006-06-01

    Climate change is being experienced particularly intensely in the Arctic. Arctic average temperature has risen at almost twice the rate as that of the rest of the world in the past few decades. Widespread melting of glaciers and sea ice and rising permafrost temperatures present additional evidence of strong Arctic warming. These changes in the Arctic provide an early indication of the environmental and societal significance of global consequences. The Arctic also provides important natural resources to the rest of the world (such as oil, gas, and fish) that will be affected by climate change, and the melting of Arctic glaciers is one of the factors contributing to sea level rise around the globe. An acceleration of these climatic trends is projected to occur during this century, due to ongoing increases in concentrations of greenhouse gases in the Earth's atmosphere. These Arctic changes will, in turn, impact the planet as a whole.

  9. Cenozoic climate change influences mammalian evolutionary dynamics.

    PubMed

    Figueirido, Borja; Janis, Christine M; Pérez-Claros, Juan A; De Renzi, Miquel; Palmqvist, Paul

    2012-01-17

    Global climate change is having profound impacts on the natural world. However, climate influence on faunal dynamics at macroevolutionary scales remains poorly understood. In this paper we investigate the influence of climate over deep time on the diversity patterns of Cenozoic North American mammals. We use factor analysis to identify temporally correlated assemblages of taxa, or major evolutionary faunas that we can then study in relation to climatic change over the past 65 million years. These taxa can be grouped into six consecutive faunal associations that show some correspondence with the qualitative mammalian chronofaunas of previous workers. We also show that the diversity pattern of most of these chronofaunas can be correlated with the stacked deep-sea benthic foraminiferal oxygen isotope (δ(18)O) curve, which strongly suggests climatic forcing of faunal dynamics over a large macroevolutionary timescale. This study demonstrates the profound influence of climate on the diversity patterns of North American terrestrial mammals over the Cenozoic.

  10. Cenozoic climate change influences mammalian evolutionary dynamics

    PubMed Central

    Figueirido, Borja; Janis, Christine M.; Pérez-Claros, Juan A.; De Renzi, Miquel; Palmqvist, Paul

    2012-01-01

    Global climate change is having profound impacts on the natural world. However, climate influence on faunal dynamics at macroevolutionary scales remains poorly understood. In this paper we investigate the influence of climate over deep time on the diversity patterns of Cenozoic North American mammals. We use factor analysis to identify temporally correlated assemblages of taxa, or major evolutionary faunas that we can then study in relation to climatic change over the past 65 million years. These taxa can be grouped into six consecutive faunal associations that show some correspondence with the qualitative mammalian chronofaunas of previous workers. We also show that the diversity pattern of most of these chronofaunas can be correlated with the stacked deep-sea benthic foraminiferal oxygen isotope (δ18O) curve, which strongly suggests climatic forcing of faunal dynamics over a large macroevolutionary timescale. This study demonstrates the profound influence of climate on the diversity patterns of North American terrestrial mammals over the Cenozoic. PMID:22203974

  11. Climate change signal over Northern Adriatic Region

    NASA Astrophysics Data System (ADS)

    Zampieri, M.; Lionello, P.; Nikulin, G.

    2009-04-01

    In this study we collect the results of several regional climate models from various projects (PRUDENCE, ENSEMBLES, and others). Temperature, precipitation, Sea Level Pressure, 500hPa geopotential height and wind speed are analyzed for Venetia and the Northern Adriatic region. The agreement among models is analyzed for the control runs and for the scenario simulations, and the dispersion among models is evaluated. The importance of resolutions is addressed as well as the changes of climate extremes in future scenarios.

  12. [Climate change and Kyoto protocol].

    PubMed

    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.

  13. Perception of climate change.

    PubMed

    Hansen, James; Sato, Makiko; Ruedy, Reto

    2012-09-11

    "Climate dice," describing the chance of unusually warm or cool seasons, have become more and more "loaded" in the past 30 y, coincident with rapid global warming. The distribution of seasonal mean temperature anomalies has shifted toward higher temperatures and the range of anomalies has increased. An important change is the emergence of a category of summertime extremely hot outliers, more than three standard deviations (3σ) warmer than the climatology of the 1951-1980 base period. This hot extreme, which covered much less than 1% of Earth's surface during the base period, now typically covers about 10% of the land area. It follows that we can state, with a high degree of confidence, that extreme anomalies such as those in Texas and Oklahoma in 2011 and Moscow in 2010 were a consequence of global warming because their likelihood in the absence of global warming was exceedingly small. We discuss practical implications of this substantial, growing, climate change. PMID:22869707

  14. Perception of climate change.

    PubMed

    Hansen, James; Sato, Makiko; Ruedy, Reto

    2012-09-11

    "Climate dice," describing the chance of unusually warm or cool seasons, have become more and more "loaded" in the past 30 y, coincident with rapid global warming. The distribution of seasonal mean temperature anomalies has shifted toward higher temperatures and the range of anomalies has increased. An important change is the emergence of a category of summertime extremely hot outliers, more than three standard deviations (3σ) warmer than the climatology of the 1951-1980 base period. This hot extreme, which covered much less than 1% of Earth's surface during the base period, now typically covers about 10% of the land area. It follows that we can state, with a high degree of confidence, that extreme anomalies such as those in Texas and Oklahoma in 2011 and Moscow in 2010 were a consequence of global warming because their likelihood in the absence of global warming was exceedingly small. We discuss practical implications of this substantial, growing, climate change.

  15. Projections of Future Climate Change

    SciTech Connect

    Cubasch, U.; Meehl , G.; Boer, G. J.; Stouffer, Ron; Dix, M.; Noda, A.; Senior, C. A.; Raper, S.; Yap, K. S.; Abe-Ouchi, A.; Brinkop, S.; Claussen, M.; Collins, M.; Evans, J.; Fischer-Bruns, I.; Flato, G.; Fyfe, J. C.; Ganopolski, A.; Gregory, J. M.; Hu, Z. Z.; Joos, Fortunat; Knutson, T.; Knutti, R.; Landsea, C.; Mearns, L. O.; Milly, C.; Mitchell, J. F.; Nozawa, T.; Paeth, H.; Raisanen, J.; Sausen, R.; Smith, Steven J.; Stocker, T.; Timmermann, A.; Ulbrich, U.; Weaver, A.; Wegner, J.; Whetton, P.; Wigley, T. M.; Winton, M.; Zwiers, F.; Kim, J. W.; Stone, J.

    2001-10-01

    Contents: Executive Summary 9.1 Introduction 9.2 Climate and Climate Change 9.3 Projections of Climate Change 9.4 General Summary Appendix 9.1: Tuning of a Simple Climate Model toAOGCM Results References

  16. Confronting Climate Change

    NASA Astrophysics Data System (ADS)

    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.

  17. [Keynote address: Climate change

    SciTech Connect

    Forrister, D.

    1994-12-31

    Broadly speaking, the climate issue is moving from talk to action both in the United States and internationally. While few nations have adopted strict controls or stiff new taxes, a number of them are developing action plans that are making clear their intention to ramp up activity between now and the year 2000... and beyond. There are sensible, economically efficient strategies to be undertaken in the near term that offer the possibility, in many countries, to avoid more draconian measures. These strategies are by-and-large the same measures that the National Academy of Sciences recommended in a 1991 report called, Policy Implications of Greenhouse Warming. The author thinks the Academy`s most important policy contribution was how it recommended the nations act in the face of uncertain science and high risks--that cost effective measures are adopted as cheap insurance... just as nations insure against other high risk, low certainty possibilities, like catastrophic health insurance, auto insurance, and fire insurance. This insurance theme is still right. First, the author addresses how the international climate change negotiations are beginning to produce insurance measures. Next, the author will discuss some of the key issues to watch in those negotiations that relate to longer-term insurance. And finally, the author will report on progress in the United States on the climate insurance plan--The President`s Climate Action Plan.

  18. Incorporating Student Activities into Climate Change Education

    NASA Astrophysics Data System (ADS)

    Steele, H.; Kelly, K.; Klein, D.; Cadavid, A. C.

    2013-12-01

    atmospheric circulation with applications of the Lorenz model, explored the land-sea breeze problem with the Dynamics and Thermodynamics Circulation Model (DTDM), and developed simple radiative transfer models. Class projects explored the effects of varying the content of CO2 and CH4 in the atmosphere, as well as the properties of paleoclimates in atmospheric simulations using EdGCM. Initial assessment of student knowledge, attitudes, and behaviors associated with these activities, particularly about climate change, was measured. Pre- and post-course surveys provided student perspectives about the courses and their learning about remote sensing and climate change concepts. Student performance on the tutorials and course projects evaluated students' ability to learn and apply their knowledge about climate change and skills with remote sensing to assigned problems or proposed projects of their choice. Survey and performance data illustrated that the exercises were successful in meeting their intended learning objectives as well as opportunities for further refinement and expansion.

  19. Recent changes in Antarctic Sea Ice.

    PubMed

    Turner, John; Hosking, J Scott; Bracegirdle, Thomas J; Marshall, Gareth J; Phillips, Tony

    2015-07-13

    In contrast to the Arctic, total sea ice extent (SIE) across the Southern Ocean has increased since the late 1970s, with the annual mean increasing at a rate of 186×10(3) km(2) per decade (1.5% per decade; p<0.01) for 1979-2013. However, this overall increase masks larger regional variations, most notably an increase (decrease) over the Ross (Amundsen-Bellingshausen) Sea. Sea ice variability results from changes in atmospheric and oceanic conditions, although the former is thought to be more significant, since there is a high correlation between anomalies in the ice concentration and the near-surface wind field. The Southern Ocean SIE trend is dominated by the increase in the Ross Sea sector, where the SIE is significantly correlated with the depth of the Amundsen Sea Low (ASL), which has deepened since 1979. The depth of the ASL is influenced by a number of external factors, including tropical sea surface temperatures, but the low also has a large locally driven intrinsic variability, suggesting that SIE in these areas is especially variable. Many of the current generation of coupled climate models have difficulty in simulating sea ice. However, output from the better-performing IPCC CMIP5 models suggests that the recent increase in Antarctic SIE may be within the bounds of intrinsic/internal variability.

  20. Designing Global Climate Change

    NASA Astrophysics Data System (ADS)

    Griffith, P. C.; ORyan, C.

    2012-12-01

    In a time when sensationalism rules the online world, it is best to keep things short. The people of the online world are not passing back and forth lengthy articles, but rather brief glimpses of complex information. This is the target audience we attempt to educate. Our challenge is then to attack not only ignorance, but also apathy toward global climate change, while conforming to popular modes of learning. When communicating our scientific material, it was difficult to determine what level of information was appropriate for our audience, especially with complex subject matter. Our unconventional approach for communicating the carbon crisis as it applies to global climate change caters to these 'recreational learners'. Using story-telling devices acquired from Carolyne's biomedical art background coupled with Peter's extensive knowledge of carbon cycle and ecosystems science, we developed a dynamic series of illustrations that capture the attention of a callous audience. Adapting complex carbon cycle and climate science into comic-book-style animations creates a channel between artist, scientist, and the general public. Brief scenes of information accompanied by text provide a perfect platform for visual learners, as well as fresh portrayals of stale material for the jaded. In this way art transcends the barriers of the cerebral and the abstract, paving the road to understanding.;

  1. Climate change and child health.

    PubMed

    Seal, Arnab; Vasudevan, Chakrapani

    2011-12-01

    Postindustrial human activity has contributed to rising atmospheric levels of greenhouse gases causing global warming and climate change. The adverse effects of climate change affect children disproportionately, especially in the developing world. Urgent action is necessary to mitigate the causes and adapt to the negative effects of climate change. Paediatricians have an important role in managing the effects of climate change on children and promoting sustainable development.

  2. Ice sheet systems and sea level change.

    NASA Astrophysics Data System (ADS)

    Rignot, E. J.

    2015-12-01

    Modern views of ice sheets provided by satellites, airborne surveys, in situ data and paleoclimate records while transformative of glaciology have not fundamentally changed concerns about ice sheet stability and collapse that emerged in the 1970's. Motivated by the desire to learn more about ice sheets using new technologies, we stumbled on an unexplored field of science and witnessed surprising changes before realizing that most were coming too fast, soon and large. Ice sheets are integrant part of the Earth system; they interact vigorously with the atmosphere and the oceans, yet most of this interaction is not part of current global climate models. Since we have never witnessed the collapse of a marine ice sheet, observations and exploration remain critical sentinels. At present, these observations suggest that Antarctica and Greenland have been launched into a path of multi-meter sea level rise caused by rapid climate warming. While the current loss of ice sheet mass to the ocean remains a trickle, every mm of sea level change will take centuries of climate reversal to get back, several major marine-terminating sectors have been pushed out of equilibrium, and ice shelves are irremediably being lost. As glaciers retreat from their salty, warm, oceanic margins, they will melt away and retreat slower, but concerns remain about sea level change from vastly marine-based sectors: 2-m sea level equivalent in Greenland and 23-m in Antarctica. Significant changes affect 2/4 marine-based sectors in Greenland - Jakobshavn Isb. and the northeast stream - with Petermann Gl. not far behind. Major changes have affected the Amundsen Sea sector of West Antarctica since the 1980s. Smaller yet significant changes affect the marine-based Wilkes Land sector of East Antarctica, a reminder that not all marine-based ice is in West Antarctica. Major advances in reducing uncertainties in sea level projections will require massive, interdisciplinary efforts that are not currently in place

  3. Climatic change on Mars.

    PubMed

    Sagan, C; Toon, O B; Gierasch, P J

    1973-09-14

    The equatorial sinuous channels on Mars detected by Mariner 9 point to a past epoch of higher pressures and abundant liquid water. Advective instability of the martian atmosphere permits two stable climates-one close to present conditions, the other at a pressure of the order of 1 bar depending on the quantity of buried volatiles. Variations in the obliquity of Mars, the luminosity of the sun, and the albedo of the polar caps each appear capable of driving the instability between a current ice age and more clement conditions. Obliquity driving alone implies that epochs of much higher and of much lower pressure must have characterized martian history. Climatic change on Mars may have important meteorological, geological, and biological implications.

  4. Climate Records of Snow, Glaciers and Sea Ice

    NASA Astrophysics Data System (ADS)

    Ballagh, L.; Dye, D.; Howard, A.; Fetterer, F.

    2005-12-01

    Cryospheric data can be used to study global climate change. For example, various environmental factors contribute to changes in annual and interannual snow cover, glacier terminus movement and anomalies of sea ice extent. Archiving and making the data easily accessible is important. At the National Snow and Ice Data Center (NSIDC), three data sets in particular exhibit characteristics that allow for understanding global climate change. Users can analyze glacier retreat from historical glacier photographs, study changes in sea ice by reviewing historical ice charts, and review changes in the annual autumn snow cover onset and last day of snow cover in the Northern Hemisphere. By including a temporal component, the Timing and Statistics of Autumn and Spring Annual Snow Cover for the Northern Hemisphere data set is useful for analyzing statistics of snow cover timing and their relation to other environmental phenomena, for example, vegetation growth dynamics. The Online Glacier Photograph Database, which contains approximately 3,000 images, provides online search and order options for photographs that were previously in risk of deterioration. The Arctic Sea Ice Charts, 1953-1986: W. Dehn Collection data set includes ice charts of the Canadian and Alaskan Arctic Ocean that can be browsed by region and date range. Previously, these ice charts were archived in analog format and in need of long-term preservation. The NOAA Climate Database Modernization Program (CDMP) supported the digitization of both the historical photographs and the sea ice charts. By evaluating these data sets, users will have the opportunity to better interpret climatic change related to snow cover, sea ice and glacier retreat.

  5. Climate Sensitivity, Sea Level, and Atmospheric Carbon Dioxide

    NASA Technical Reports Server (NTRS)

    Hansen, James; Sato, Makiko; Russell, Gary; Kharecha, Pushker

    2013-01-01

    Cenozoic temperature, sea level and CO2 covariations provide insights into climate sensitivity to external forcings and sea-level sensitivity to climate change. Climate sensitivity depends on the initial climate state, but potentially can be accurately inferred from precise palaeoclimate data. Pleistocene climate oscillations yield a fast-feedback climate sensitivity of 3+/-1deg C for a 4 W/sq m CO2 forcing if Holocene warming relative to the Last Glacial Maximum (LGM) is used as calibration, but the error (uncertainty) is substantial and partly subjective because of poorly defined LGM global temperature and possible human influences in the Holocene. Glacial-to-interglacial climate change leading to the prior (Eemian) interglacial is less ambiguous and implies a sensitivity in the upper part of the above range, i.e. 3-4deg C for a 4 W/sq m CO2 forcing. Slow feedbacks, especially change of ice sheet size and atmospheric CO2, amplify the total Earth system sensitivity by an amount that depends on the time scale considered. Ice sheet response time is poorly defined, but we show that the slow response and hysteresis in prevailing ice sheet models are exaggerated. We use a global model, simplified to essential processes, to investigate state dependence of climate sensitivity, finding an increased sensitivity towards warmer climates, as low cloud cover is diminished and increased water vapour elevates the tropopause. Burning all fossil fuels, we conclude, would make most of the planet uninhabitable by humans, thus calling into question strategies that emphasize adaptation to climate change.

  6. Climate sensitivity, sea level and atmospheric carbon dioxide

    PubMed Central

    Hansen, James; Sato, Makiko; Russell, Gary; Kharecha, Pushker

    2013-01-01

    Cenozoic temperature, sea level and CO2 covariations provide insights into climate sensitivity to external forcings and sea-level sensitivity to climate change. Climate sensitivity depends on the initial climate state, but potentially can be accurately inferred from precise palaeoclimate data. Pleistocene climate oscillations yield a fast-feedback climate sensitivity of 3±1°C for a 4 W m−2 CO2 forcing if Holocene warming relative to the Last Glacial Maximum (LGM) is used as calibration, but the error (uncertainty) is substantial and partly subjective because of poorly defined LGM global temperature and possible human influences in the Holocene. Glacial-to-interglacial climate change leading to the prior (Eemian) interglacial is less ambiguous and implies a sensitivity in the upper part of the above range, i.e. 3–4°C for a 4 W m−2 CO2 forcing. Slow feedbacks, especially change of ice sheet size and atmospheric CO2, amplify the total Earth system sensitivity by an amount that depends on the time scale considered. Ice sheet response time is poorly defined, but we show that the slow response and hysteresis in prevailing ice sheet models are exaggerated. We use a global model, simplified to essential processes, to investigate state dependence of climate sensitivity, finding an increased sensitivity towards warmer climates, as low cloud cover is diminished and increased water vapour elevates the tropopause. Burning all fossil fuels, we conclude, would make most of the planet uninhabitable by humans, thus calling into question strategies that emphasize adaptation to climate change. PMID:24043864

  7. Agriculture and climate change

    SciTech Connect

    Abelson, P.H.

    1992-07-03

    How will increases in levels of CO{sub 2} and changes in temperature affect food production A recently issued report analyzes prospects for US agriculture 1990 to 2030. The report, prepared by a distinguished Task Force, first projects the evolution of agriculture assuming increased levels of CO{sub 2} but no climate change. Then it deals with effects of climate change, followed by a discussion of how greenhouse emissions might be diminished by agriculture. Economic and policy matters are also covered. How the climate would respond to more greenhouse gases is uncertain. If temperatures were higher, there would be more evaporation and more precipitation. Where would the rain fall That is a good question. Weather in a particular locality is not determined by global averages. The Dust Bowl of the 1930s could be repeated at its former site or located in another region such as the present Corn Belt. But depending on the realities at a given place, farmers have demonstrated great flexibility in choosing what they may grow. Their flexibility has been increased by the numerous varieties of seeds of major crops that are now available, each having different characteristics such as drought resistance and temperature tolerance. In past, agriculture has contributed about 5% of US greenhouse gases. Two large components have involved emissions of CO{sub 2} from farm machinery and from oxidation of organic matter in soil due to tillage. Use of diesel fuel and more efficient machinery has reduced emissions from that source by 40%. In some areas changed tillage practices are now responsible for returning carbon to the soil. The report identifies an important potential for diminishing net US emissions of CO{sub 2} by growth and utilization of biomass. Large areas are already available that could be devoted to energy crops.

  8. Sea ice-albedo climate feedback mechanism

    SciTech Connect

    Schramm, J.L.; Curry, J.A.; Ebert, E.E.

    1995-02-01

    The sea ice-albedo feedback mechanism over the Arctic Ocean multiyear sea ice is investigated by conducting a series of experiments using several one-dimensional models of the coupled sea ice-atmosphere system. In its simplest form, ice-albedo feedback is thought to be associated with a decrease in the areal cover of snow and ice and a corresponding increase in the surface temperature, further decreasing the area cover of snow and ice. It is shown that the sea ice-albedo feedback can operate even in multiyear pack ice, without the disappearance of this ice, associated with internal processes occurring within the multiyear ice pack (e.g., duration of the snow cover, ice thickness, ice distribution, lead fraction, and melt pond characteristics). The strength of the ice-albedo feedback mechanism is compared for several different thermodynamic sea ice models: a new model that includes ice thickness distribution., the Ebert and Curry model, the Mayjut and Untersteiner model, and the Semtner level-3 and level-0 models. The climate forcing is chosen to be a perturbation of the surface heat flux, and cloud and water vapor feedbacks are inoperative so that the effects of the sea ice-albedo feedback mechanism can be isolated. The inclusion of melt ponds significantly strengthens the ice-albedo feedback, while the ice thickness distribution decreases the strength of the modeled sea ice-albedo feedback. It is emphasized that accurately modeling present-day sea ice thickness is not adequate for a sea ice parameterization; the correct physical processes must be included so that the sea ice parameterization yields correct sensitivities to external forcing. 22 refs., 6 figs., 1 tab.

  9. Global climate change and emerging infectious diseases.

    PubMed

    Patz, J A; Epstein, P R; Burke, T A; Balbus, J M

    1996-01-17

    Climatic factors influence the emergence and reemergence of infectious diseases, in addition to multiple human, biological, and ecological determinants. Climatologists have identified upward trends in global temperatures and now estimate an unprecedented rise of 2.0 degrees C by the year 2100. Of major concern is that these changes can affect the introduction and dissemination of many serious infectious diseases. The incidence of mosquito-borne diseases, including malaria, dengue, and viral encephalitides, are among those diseases most sensitive to climate. Climate change would directly affect disease transmission by shifting the vector's geographic range and increasing reproductive and biting rates and by shortening the pathogen incubation period. Climate-related increases in sea surface temperature and sea level can lead to higher incidence of water-borne infectious and toxin-related illnesses, such as cholera and shellfish poisoning. Human migration and damage to health infrastructures from the projected increase in climate variability could indirectly contribute to disease transmission. Human susceptibility to infections might be further compounded by malnutrition due to climate stress on agriculture and potential alterations in the human immune system caused by increased flux of ultraviolet radiation. Analyzing the role of climate in the emergence of human infectious diseases will require interdisciplinary cooperation among physicians, climatologists, biologists, and social scientists. Increased disease surveillance, integrated modeling, and use of geographically based data systems will afford more anticipatory measures by the medical community. Understanding the linkages between climatological and ecological change as determinants of disease emergence and redistribution will ultimately help optimize preventive strategies.

  10. Geomagnetic excursions and climate change

    NASA Technical Reports Server (NTRS)

    Rampino, M. R.

    1983-01-01

    Rampino argues that although Kent (1982) demonstrated that the intensity of natural remanent magnetism (NRM) in deep-sea sediments is sensitive to changes in sediment type, and hence is not an accurate indicator of the true strength of the geomagnetic field, it does not offer an alternative explanation for the proposed connections between excursions, climate, and orbital parameters. Kent replies by illustrating some of the problems associated with geomagnetic excursions by considering the record of proposed excursions in a single critical core. The large departure from an axial dipole field direction seen in a part of the sample is probably due to a distorted record; the drawing and storage of the sample, which is described, could easily have led to disturbance and distortion of the record.

  11. Spatial and temporal Teleconnections of Sea Surface Temperature and Ocean Indices to regional Climate Variations across Thailand - a Pathway to understanding the Impact of Climate Change on Water Resources

    NASA Astrophysics Data System (ADS)

    Bejranonda, Werapol; Koch, Manfred

    2010-05-01

    Thailand has a long coastline with the Pacific Ocean, as part of the Gulf of Thailand, as well as with the Indian Ocean, as part of the Andaman Sea. Because of this peculiar location, Thailand's local climate and, in particular, its water resources are strongly influenced by the mix of tropical wet, tropical dry and tropical monsoon seasons. Because of the large seasonal and interannual variations and irregularities of these, mainly ocean-driven weather patterns, particularly in recent times, large-scale water storage in huge river-fed reservoirs has a long tradition in Thailand, providing water for urban, industrial and agricultural use during long dry seasonal periods. These reservoirs which are located all over Thailand gather water primarily from monsoon-driven rainfall during the wet season which, usually, lasts from May to October. During the dry season, November to April, when the monsoon winds move northward, the air masses are drier in central and northern Thailand, with rain falling here only a few days in a month. Southern Thailand, on the other hand, which is constituted mostly by the isthmus between the two oceans, stays even hot and humid during that time period. Because of this tropical climate pattern, the surface water resources in most of Thailand strongly hinge on the monsoon movements which, in turn, depend themselves upon the thermal states of the Pacific and Indian Oceans. Therefore, the understanding of the recent strong seasonal and interannual climate variations with their detrimental effects on the availability of hydrological water resources in most parts of Thailand, must include the analysis of changes of various sea-state indices in the adjacent oceans and of their possible teleconnections with regional climate indices across this country. With the modern coupled atmospheric-ocean models being able to predict the variations of many ocean indices over a period of several months, namely, those driven by El Nino- Southern Oscillations

  12. Insects and climate change

    SciTech Connect

    Elias, S.A. )

    1991-09-01

    In this article the author describes some of the significant late glacial and Holocene changes that occurred in the Rocky Mountains, including the regional extirpation of certain beetle species. The fossil data presented here summarize what is known about regional insect responses to climate change in terms of species stability and geographic distribution. To minimize potential problems of species interactions (i.e., insect-host plant relationships, host-parasite relationships, and other interactions that tie a particular insect species' distribution to that of another organism), only predators and scavengers are discussed. These insects respond most rapidly to environmental changes, because for the most part they are not tied to any particular type of vegetation.

  13. Changes in deep-sea fish and crustacean communities at 1000-2200 m in the Western Mediterranean after 25 years: Relation to hydro-climatic conditions

    NASA Astrophysics Data System (ADS)

    Cartes, J. E.; Maynou, F.; Fanelli, E.; López-Pérez, C.; Papiol, V.

    2015-03-01

    toward these intermediate depths that acquired greater trophic resources. Deep-sea Mediterranean fish and invertebrates, including important commercial species, seemed to undergo long-term changes in its distribution and biomass due to changes in hydro-climatic conditions, mainly a decrease of O2 in the bottom-boundary layer.

  14. Climate change in the sea: the implications of increasing the carbon dioxide inputs to the surface ocean

    SciTech Connect

    Pfister, Cathy

    2012-12-23

    The oceans are estimated to be absorbing one-third of the fossil fuel carbon released into the atmosphere, a process that is expected to change ocean carbon chemistry. I will present data from the Washington coast showing ocean pH declines and changes to the shell chemistry of bivalves. I will discuss implications of carbon cycle changes for marine species, including insights from a coastal area where I have worked for more than 24 years. I will summarize what we know to date about this process of “ocean acidification”.

  15. Ruminants, climate change and climate policy

    NASA Astrophysics Data System (ADS)

    Ripple, William J.; Smith, Pete; Haberl, Helmut; Montzka, Stephen A.; McAlpine, Clive; Boucher, Douglas H.

    2014-01-01

    Greenhouse gas emissions from ruminant meat production are significant. Reductions in global ruminant numbers could make a substantial contribution to climate change mitigation goals and yield important social and environmental co-benefits.

  16. Climate Change on Mars

    NASA Technical Reports Server (NTRS)

    Haberle, R. M.; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    Today, Mars is cold and dry. With a 7 mbar mean surface pressure, its thin predominantly CO2 atmosphere is not capable of raising global mean surface temperatures significantly above its 217K effective radiating temperature, and the amount of water vapor in the atmosphere is equivalent to a global ocean only 10 microns deep. Has Mars always been in such a deep freeze? There are several lines of evidence that suggest it has not. First, there are the valley networks which are found throughout the heavily cratered terrains. These features are old (3.8 Gyr) and appear to require liquid water to form. A warm climate early in Mars' history has often been invoked to explain them, but the precise conditions required to achieve this have yet to be determined. Second, some of the features seen in orbiter images of the surface have been interpreted in terms of glacial activity associated with an active hydrological cycle some several billion years ago. This interpretation is controversial as it requires the release of enormous quantities of ground water and enough greenhouse warming to raise temperatures to the melting point. Finally, there are the layered terrains that characterize both polar regions. These terrains are geologically young (10 Myr) and are believed to have formed by the slow and steady deposition of dust and water ice from the atmosphere. The individual layers result from the modulation of the deposition rate which is driven by changes in Mars' orbital parameters. The ongoing research into each of these areas of Martian climate change will be reviewed, and similarities to the Earth's climate system will be noted.

  17. Permafrost and Climate Change

    NASA Astrophysics Data System (ADS)

    Basnet, S.; Shahroudi, N.

    2012-12-01

    This paper examines the effects of climate change on Permafrost. Climate change has been shown to have a global correlation with decreased snow cover in high latitudes. In the current research station and satellite data were used to detect the location of permafrost. Permafrost is dependent on the temperature of the ground surface. Air temperature and snow cover from Integrated Surface Database (ISD) downloaded from National Climatic Data Center (NCDC) were observed for six consecutive years (1999-2004). The research was carried out over the entire globe to study the trend between fluctuating temperature and snow cover. Number of days with temperature below zero (freezing) and above zero (melting) was counted over a 6-year period. It was observed that each year the area of ice cover decreased by 0.3% in the Northern Hemisphere; a 1% increase in air temperature was also observed. Furthermore, the results from station data for snow cover and air temperature were compared with the snow cover and skin temperature from the satellite data. The skin temperature was retrieved from infrared (IR) radiance at International Satellite Cloud Climatology Project (ISCCP) and the snow cover is derived from visible satellite data at The National Environmental Satellite, Data, and Information Service (NESDIS), part of the National Oceanic and Atmospheric Administration (NOAA). Both dataset projected that the higher latitudes had the highest number of days with temperature below zero degree Celsius and these locations will be able to house permafrost. In order to improve the data quality as well as for more accurate results, in the future ISD data and satellite skin temperature will be analyzed for longer period of time (1979-2011) and (1983-2007) respectively also, two additional station data will be studied. The two datasets for future studies are Integrated Global Radiosonde Archive (IGRA) and International Comprehensive Ocean-Atmosphere Data Set (ICOADS). The results outputted by

  18. Communicating Climate Change (Invited)

    NASA Astrophysics Data System (ADS)

    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.

  19. Climate Change: Prospects for Nature

    SciTech Connect

    Thomas Lovejoy

    2008-03-12

    Thomas Lovejoy, President of The H. John Heinz III Center for Science, Economics and the Environment, explores the impact of climate change on the natural world. He also discusses the implications of climate change for climate policy and natural resource management.

  20. Climatic changes and variations: a geophysical problem

    SciTech Connect

    Newell, R. E.; Chiu, L. S.

    1980-01-01

    The morphology of, and the physical factors that control, the seasonal changes in global free air temperature and sea surface temperature are discussed. Non-seasonal tropical free air temperature changes are related to preceeding changes in tropical sea surface temperature and to volcanic aerosol while the tropical sea surface temperature itself is related to changes in surface pressure which characterize the Southern Oscillation. Zonal wind variations at low latitudes accompany the latter variations. The main variability in tropospheric temperature at high latitudes is characterized by the Greenland seesaw. The injection of volcanic aerosol by the eruption of Mt. Agung in March 1963 into the stratosphere gives rise to temperature increases of up to 5/sup 0/C in the stratosphere and cooling of 1/sup 0/C in the troposphere. The third major climatic signal in the recent record - the so called Biennial oscillation - is also briefly reviewed.

  1. Identifying uncertainties in Arctic climate change projections

    NASA Astrophysics Data System (ADS)

    Hodson, Daniel L. R.; Keeley, Sarah P. E.; West, Alex; Ridley, Jeff; Hawkins, Ed; Hewitt, Helene T.

    2013-06-01

    Wide ranging climate changes are expected in the Arctic by the end of the 21st century, but projections of the size of these changes vary widely across current global climate models. This variation represents a large source of uncertainty in our understanding of the evolution of Arctic climate. Here we systematically quantify and assess the model uncertainty in Arctic climate changes in two CO2 doubling experiments: a multimodel ensemble (CMIP3) and an ensemble constructed using a single model (HadCM3) with multiple parameter perturbations (THC-QUMP). These two ensembles allow us to assess the contribution that both structural and parameter variations across models make to the total uncertainty and to begin to attribute sources of uncertainty in projected changes. We find that parameter uncertainty is an major source of uncertainty in certain aspects of Arctic climate. But also that uncertainties in the mean climate state in the 20th century, most notably in the northward Atlantic ocean heat transport and Arctic sea ice volume, are a significant source of uncertainty for projections of future Arctic change. We suggest that better observational constraints on these quantities will lead to significant improvements in the precision of projections of future Arctic climate change.

  2. Relating Regional Arctic Sea Ice and climate extremes over Europe

    NASA Astrophysics Data System (ADS)

    Ionita-Scholz, Monica; Grosfeld, Klaus; Lohmann, Gerrit; Scholz, Patrick

    2016-04-01

    The potential increase of temperature extremes under climate change is a major threat to society, as temperature extremes have a deep impact on environment, hydrology, agriculture, society and economy. Hence, the analysis of the mechanisms underlying their occurrence, including their relationships with the large-scale atmospheric circulation and sea ice concentration, is of major importance. At the same time, the decline in Arctic sea ice cover during the last 30 years has been widely documented and it is clear that this change is having profound impacts at regional as well as planetary scale. As such, this study aims to investigate the relation between the autumn regional sea ice concentration variability and cold winters in Europe, as identified by the numbers of cold nights (TN10p), cold days (TX10p), ice days (ID) and consecutive frost days (CFD). We analyze the relationship between Arctic sea ice variation in autumn (September-October-November) averaged over eight different Arctic regions (Barents/Kara Seas, Beaufort Sea, Chukchi/Bering Seas, Central Arctic, Greenland Sea, Labrador Sea/Baffin Bay, Laptev/East Siberian Seas and Northern Hemisphere) and variations in atmospheric circulation and climate extreme indices in the following winter season over Europe using composite map analysis. Based on the composite map analysis it is shown that the response of the winter extreme temperatures over Europe is highly correlated/connected to changes in Arctic sea ice variability. However, this signal is not symmetrical for the case of high and low sea ice years. Moreover, the response of temperatures extreme over Europe to sea ice variability over the different Arctic regions differs substantially. The regions which have the strongest impact on the extreme winter temperature over Europe are: Barents/Kara Seas, Beaufort Sea, Central Arctic and the Northern Hemisphere. For the years of high sea ice concentration in the Barents/Kara Seas there is a reduction in the number

  3. Wave climate of the White Sea

    NASA Astrophysics Data System (ADS)

    Arkhipkin, Victor; Dobrolyubov, Sergey; Myslenkov, Stanislav; Korablina, Anastasia

    2016-04-01

    The implementation of the SWAN spectral wave model for the White Sea with using unstructured grid was presented. The main area of the Barents Sea was added to calculation region because it produces swell which incomes to the White Sea from the outside. Spatial resolution of unstructured grid is 500 m-5 km for the White Sea and 10-20 km for the Barents sea. NCEP/CFSR (~0.3°) input wind forcing was used. The results of the numerical modeling include wind wave fields for the White Sea with time step of 3 hours from 1979 to 2010. Spatial extreme value analysis of significant wave heights was performed. The storm situations, when the significant wave height exceeded 3 and 4 meters, were identified for the 32-year period. It allowed to analyze the variability of wind wave climate in the White Sea. The storminess of the White Sea tended to increase from 1979 to 1991, then decreased to minimum at 2000 and increased again till 2010. This work showed the following results. For example, in the Voronka (part of the White Sea) the synoptic situations with a wave height of more than 2 m (50-60 cases) took place about three times more than in the Basin (part of the White Sea), with heights of more than 3 m (25-40 cases) five or six times more. Cases with wave heights greater than 5 m in the Basin is extremely rare, while in the Voronka they occur 10 times a year. The significant wave height of a possible one time in 100 years is up to 7 meters in the Basin, up to 13 m in the Voronka, up to 3 m in the Onega Bay. In May, the smallest wavelength occurs in the Onega Bay, and is only 25 m. In the Basin wavelength is increased to 50 m. The longer wavelengths observed in the Voronka - 100 m. In November in the Basin (especially in the western part) and in the Voronka wavelength greatly increased to 75 and 200 m, respectively. In May, in the Onega Bay, Basin and Gorlo (part of the White Sea) swell height does not exceed 1 m. Only in the Voronka, it increases up to 3 meters. By November

  4. Effects of expected global climate change on marine faunas.

    PubMed

    Fields, P A; Graham, J B; Rosenblatt, R H; Somero, G N

    1993-10-01

    Anthropogenically induced global climate change is likely to have a major impact on marine ecosystems, affecting both biodiversity and productivity. These changes will, in turn, have a large impact on humankind's interactions with the sea. By examining the effects of past climate changes on the ocean, as well as by determining how shifts in physical parameters of the ocean may affect physiology, biochemistry and community interactions, scientists are beginning to explore the possible effects of global climate change on marine biota.

  5. Tools for Teaching Climate Change Studies

    SciTech Connect

    Maestas, A.M.; Jones, L.A.

    2005-03-18

    discussing the impacts of climate change on land, sea, and other aspects of village life.

  6. Importance of Sea Ice for Validating Global Climate Models

    NASA Technical Reports Server (NTRS)

    Geiger, Cathleen A.

    1997-01-01

    Reproduction of current day large-scale physical features and processes is a critical test of global climate model performance. Without this benchmark, prognoses of future climate conditions are at best speculation. A fundamental question relevant to this issue is, which processes and observations are both robust and sensitive enough to be used for model validation and furthermore are they also indicators of the problem at hand? In the case of global climate, one of the problems at hand is to distinguish between anthropogenic and naturally occuring climate responses. The polar regions provide an excellent testing ground to examine this problem because few humans make their livelihood there, such that anthropogenic influences in the polar regions usually spawn from global redistribution of a source originating elsewhere. Concomitantly, polar regions are one of the few places where responses to climate are non-anthropogenic. Thus, if an anthropogenic effect has reached the polar regions (e.g. the case of upper atmospheric ozone sensitivity to CFCs), it has most likely had an impact globally but is more difficult to sort out from local effects in areas where anthropogenic activity is high. Within this context, sea ice has served as both a monitoring platform and sensitivity parameter of polar climate response since the time of Fridtjof Nansen. Sea ice resides in the polar regions at the air-sea interface such that changes in either the global atmospheric or oceanic circulation set up complex non-linear responses in sea ice which are uniquely determined. Sea ice currently covers a maximum of about 7% of the earth's surface but was completely absent during the Jurassic Period and far more extensive during the various ice ages. It is also geophysically very thin (typically <10 m in Arctic, <3 m in Antarctic) compared to the troposphere (roughly 10 km) and deep ocean (roughly 3 to 4 km). Because of these unique conditions, polar researchers regard sea ice as one of the

  7. Climate change and health in Earth's future

    NASA Astrophysics Data System (ADS)

    Bowles, Devin C.; Butler, Colin D.; Friel, Sharon

    2014-02-01

    Threats to health from climate change are increasingly recognized, yet little research into the effects upon health systems is published. However, additional demands on health systems are increasingly documented. Pathways include direct weather impacts, such as amplified heat stress, and altered ecological relationships, including alterations to the distribution and activity of pathogens and vectors. The greatest driver of demand on future health systems from climate change may be the alterations to socioeconomic systems; however, these "tertiary effects" have received less attention in the health literature. Increasing demands on health systems from climate change will impede health system capacity. Changing weather patterns and sea-level rise will reduce food production in many developing countries, thus fostering undernutrition and concomitant disease susceptibility. Associated poverty will impede people's ability to access and support health systems. Climate change will increase migration, potentially exposing migrants to endemic diseases for which they have limited resistance, transporting diseases and fostering conditions conducive to disease transmission. Specific predictions of timing and locations of migration remain elusive, hampering planning and misaligning needs and infrastructure. Food shortages, migration, falling economic activity, and failing government legitimacy following climate change are also "risk multipliers" for conflict. Injuries to combatants, undernutrition, and increased infectious disease will result. Modern conflict often sees health personnel and infrastructure deliberately targeted and disease surveillance and eradication programs obstructed. Climate change will substantially impede economic growth, reducing health system funding and limiting health system adaptation. Modern medical care may be snatched away from millions who recently obtained it.

  8. AO/NAO Response to Climate Change. 1; Respective Influences of Stratospheric and Tropospheric Climate Changes

    NASA Technical Reports Server (NTRS)

    Rind, D.; Perlwitz, J.; Lonergan, P.

    2005-01-01

    We utilize the GISS Global Climate Middle Atmosphere Model and 8 different climate change experiments, many of them focused on stratospheric climate forcings, to assess the relative influence of tropospheric and stratospheric climate change on the extratropical circulation indices (Arctic Oscillation, AO; North Atlantic Oscillation, NAO). The experiments are run in two different ways: with variable sea surface temperatures (SSTs) to allow for a full tropospheric climate response, and with specified SSTs to minimize the tropospheric change. The results show that tropospheric warming (cooling) experiments and stratospheric cooling (warming) experiments produce more positive (negative) AO/NAO indices. For the typical magnitudes of tropospheric and stratospheric climate changes, the tropospheric response dominates; results are strongest when the tropospheric and stratospheric influences are producing similar phase changes. Both regions produce their effect primarily by altering wave propagation and angular momentum transports, but planetary wave energy changes accompanying tropospheric climate change are also important. Stratospheric forcing has a larger impact on the NAO than on the AO, and the angular momentum transport changes associated with it peak in the upper troposphere, affecting all wavenumbers. Tropospheric climate changes influence both the A0 and NAO with effects that extend throughout the troposphere. For both forcings there is often vertical consistency in the sign of the momentum transport changes, obscuring the difference between direct and indirect mechanisms for influencing the surface circulation.

  9. Climate variability, climate change, and fisheries

    SciTech Connect

    Glantz, M.H.

    1992-01-01

    This book contains 15 case studies of the ups and downs of fisheries. Each author focuses on the uncertainties of forecasting for fisheries and offers conclusions on the possible impacts of climatic change. Problems of forecasting for fisheries discussed in the book include the following: inadequate models; alterations in industrial structures;climatic events;habitat loss; interrelationships among life history, industry, society, and ecological processes; sociopolitical factors; predatory-parasitic species irruptions;climatic oceanographic factors; international fisheries politics and technology; large scale fluctuations in a coastal fisheries. The book presents the array of problems faced by scientists, fishery managers, and policy makers, and summarizes with general conclusions.

  10. Serious Simulation Role-Playing Games for Transformative Climate Change Education: "World Climate" and "Future Climate"

    NASA Astrophysics Data System (ADS)

    Rooney-Varga, J. N.; Sterman, J.; Sawin, E.; Jones, A.; Merhi, H.; Hunt, C.

    2012-12-01

    Climate change, its mitigation, and adaption to its impacts are among the greatest challenges of our times. Despite the importance of societal decisions in determining climate change outcomes, flawed mental models about climate change remain widespread, are often deeply entrenched, and present significant barriers to understanding and decision-making around climate change. Here, we describe two simulation role-playing games that combine active, affective, and analytical learning to enable shifts of deeply held conceptions about climate change. The games, World Climate and Future Climate, use a state-of-the-art decision support simulation, C-ROADS (Climate Rapid Overview and Decision Support) to provide users with immediate feedback on the outcomes of their mitigation strategies at the national level, including global greenhouse gas (GHG) emissions and concentrations, mean temperature changes, sea level rise, and ocean acidification. C-ROADS outcomes are consistent with the atmosphere-ocean general circulation models (AOGCMS), such as those used by the IPCC, but runs in less than one second on ordinary laptops, providing immediate feedback to participants on the consequences of their proposed policies. Both World Climate and Future Climate role-playing games provide immersive, situated learning experiences that motivate active engagement with climate science and policy. In World Climate, participants play the role of United Nations climate treaty negotiators. Participant emissions reductions proposals are continually assessed through interactive exploration of the best available science through C-ROADS. Future Climate focuses on time delays in the climate and energy systems. Participants play the roles of three generations: today's policymakers, today's youth, and 'just born.' The game unfolds in three rounds 25 simulated years apart. In the first round, only today's policymakers make decisions; In the next round, the young become the policymakers and inherit the

  11. Climate influence on deep sea populations.

    PubMed

    Company, Joan B; Puig, Pere; Sardà, Francesc; Palanques, Albert; Latasa, Mikel; Scharek, Renate

    2008-01-16

    Dynamics of biological processes on the deep-sea floor are traditionally thought to be controlled by vertical sinking of particles from the euphotic zone at a seasonal scale. However, little is known about the influence of lateral particle transport from continental margins to deep-sea ecosystems. To address this question, we report here how the formation of dense shelf waters and their subsequent downslope cascade, a climate induced phenomenon, affects the population of the deep-sea shrimp Aristeus antennatus. We found evidence that strong currents associated with intense cascading events correlates with the disappearance of this species from its fishing grounds, producing a temporary fishery collapse. Despite this initial negative effect, landings increase between 3 and 5 years after these major events, preceded by an increase of juveniles. The transport of particulate organic matter associated with cascading appears to enhance the recruitment of this deep-sea living resource, apparently mitigating the general trend of overexploitation. Because cascade of dense water from continental shelves is a global phenomenon, we anticipate that its influence on deep-sea ecosystems and fisheries worldwide should be larger than previously thought.

  12. Climate Influence on Deep Sea Populations

    PubMed Central

    Company, Joan B.; Puig, Pere; Sardà, Francesc; Palanques, Albert; Latasa, Mikel; Scharek, Renate

    2008-01-01

    Dynamics of biological processes on the deep-sea floor are traditionally thought to be controlled by vertical sinking of particles from the euphotic zone at a seasonal scale. However, little is known about the influence of lateral particle transport from continental margins to deep-sea ecosystems. To address this question, we report here how the formation of dense shelf waters and their subsequent downslope cascade, a climate induced phenomenon, affects the population of the deep-sea shrimp Aristeus antennatus. We found evidence that strong currents associated with intense cascading events correlates with the disappearance of this species from its fishing grounds, producing a temporary fishery collapse. Despite this initial negative effect, landings increase between 3 and 5 years after these major events, preceded by an increase of juveniles. The transport of particulate organic matter associated with cascading appears to enhance the recruitment of this deep-sea living resource, apparently mitigating the general trend of overexploitation. Because cascade of dense water from continental shelves is a global phenomenon, we anticipate that its influence on deep-sea ecosystems and fisheries worldwide should be larger than previously thought. PMID:18197243

  13. The Eocene-Oligocene sedimentary record in the Chesapeake Bay impact structure: Implications for climate and sea-level changes on the western Atlantic margin

    USGS Publications Warehouse

    Schulte, P.; Wade, B.S.; Kontny, A.; ,

    2009-01-01

    other northwest Atlantic margin sections. It could result from a shift to more distal depositional environments and condensed sedimentation during maximum fl ooding, rather than refl ecting a climatic change in the hinterland. The distinct 1% increase of the oxygen isotopes may correspond to the short-term latest Eocene "precursor isotope event." (4) The abrupt increase of sediment grainsize, carbonate content, and abundance of authigenic minerals (glauconite) across the major unconformity that separates Eocene from Oligocene sediments in the Eyreville core refl ects deposition in shallower settings associated with erosion, winnowing, and reworking. Sediments within the central crater were affected by the rapid eustatic sea-level changes associated with the greenhouse-icehouse transition, as well as by an abrupt major uplift event and possibly enhanced current activity on the northwestern Atlantic margin. ?? 2009 The Geological Society of America.

  14. Conflict in a changing climate

    NASA Astrophysics Data System (ADS)

    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.

  15. Climate change mitigation and adaptation in strategic environmental assessment

    SciTech Connect

    Wende, Wolfgang; Bond, Alan; Bobylev, Nikolai; Stratmann, Lars

    2012-01-15

    Countries are implementing CO{sub 2} emission reduction targets in order to meet a globally agreed global warming limit of +2 Degree-Sign C. However, it was hypothesised that these national reduction targets are not translated to regional or state level planning, and are not considered through Strategic Environmental Assessment (SEA) in order to meet emission reduction obligations falling on the transport, energy, housing, agriculture, and forestry sectors. SEAs of land use plans in the German state of Saxony, and the English region of the East of England were examined for their consideration of climate change impacts based on a set of criteria drawn from the literature. It was found that SEAs in both cases failed to consider climate change impacts at scales larger than the boundary of the spatial plan, and that CO{sub 2} reduction targets were not considered. This suggests a need for more clarity in the legal obligations for climate change consideration within the text of the SEA Directive, a requirement for monitoring of carbon emissions, a need for methodological guidance to devolve global climate change targets down to regional and local levels, and a need for guidance on properly implementing climate change protection in SEA. - Highlights: Black-Right-Pointing-Pointer Strategic Environmental Assessments (SEA) of 12 land use plans from Germany and England have been examined. Black-Right-Pointing-Pointer SEA failed to consider climate change impacts at scales larger than the boundary of the land use plans. Black-Right-Pointing-Pointer SEA should be an important instrument for climate protection. Black-Right-Pointing-Pointer Concrete steps for climate protection mainstreaming into SEA at the European Union and national levels have been suggested.

  16. Glacial climate states and abrupt climate change in MIROC AOGCM

    NASA Astrophysics Data System (ADS)

    Abe-Ouchi, Ayako; Ohgaito, Rumi; Takahashi, Kunio; Yoshimori, Masa; Kawamura, Kenji; Oka, Akira; Chan, Wing-Le; Sherriff-Tadano, Sam

    2016-04-01

    Millennial climate change such as D-O cycles and AIM recorded in ice cores in both Hemispheres is known to show a relatively higher amplitude in the middle-level of a glacial cycle than in the interglacial state or severe glacial state. Here we ran several sensitivity experiments using a coupled atmosphere and ocean GCM (MIROC4m, renamed from MIROC3.2.2) and show that the response to fresh water release to the ocean and bipolar response is highly dependent on the background climate. The experiments were conducted with 500 years water hosing of 0.05 to 0.1 Sv (where 1 Sv is equivalent to the water flux of 10m sea level rise in 100 years) in the North Atlantic 50-70N under different basic states; modern climate state with the pre-industrial condition, middle glacial climate state and full glacial condition, mainly differing in the ice sheet configuration and atmospheric amount of Greenhouse Gases. The results under middle glacial condition show largest cooling/warming response in North Atlantic and a reasonable bipolar warming/cooling signal revealed in the ice core data of the both hemisphere. We discuss the responses under different background climates which involve the strong coupling between atmosphere, ocean and sea ice and their dependence on the configuration of ice sheet.

  17. Climate change and marine plankton.

    PubMed

    Hays, Graeme C; Richardson, Anthony J; Robinson, Carol

    2005-06-01

    Understanding how climate change will affect the planet is a key issue worldwide. Questions concerning the pace and impacts of climate change are thus central to many ecological and biogeochemical studies, and addressing the consequences of climate change is now high on the list of priorities for funding agencies. Here, we review the interactions between climate change and plankton communities, focusing on systematic changes in plankton community structure, abundance, distribution and phenology over recent decades. We examine the potential socioeconomic impacts of these plankton changes, such as the effects of bottom-up forcing on commercially exploited fish stocks (i.e. plankton as food for fish). We also consider the crucial roles that plankton might have in dictating the future pace of climate change via feedback mechanisms responding to elevated atmospheric CO(2) levels. An important message emerges from this review: ongoing plankton monitoring programmes worldwide will act as sentinels to identify future changes in marine ecosystems.

  18. Changing climate and Caribbean coastlines

    SciTech Connect

    Gable, F.

    1987-01-01

    This paper examines the significance of rising relative sea level to the Caribbean region. The various factors contributing to rising relative sea level are explained -- rising eustatic sea level from atmospheric warming, natural subsidence, and manmade subsidence. The possibility of changes in storms is also raised. Possible impacts are discussed, for both wetlands and urban areas. Some developing government policies are described, such as restrictions on coastal development. International research agendas are described. A list of recommended tide-gage stations is presented.

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

    PubMed

    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. Expert credibility in climate change.

    PubMed

    Anderegg, William R L; Prall, James W; Harold, Jacob; Schneider, Stephen H

    2010-07-01

    Although preliminary estimates from published literature and expert surveys suggest striking agreement among climate scientists on the tenets of anthropogenic climate change (ACC), the American public expresses substantial doubt about both the anthropogenic cause and the level of scientific agreement underpinning ACC. A broad analysis of the climate scientist community itself, the distribution of credibility of dissenting researchers relative to agreeing researchers, and the level of agreement among top climate experts has not been conducted and would inform future ACC discussions. Here, we use an extensive dataset of 1,372 climate researchers and their publication and citation data to show that (i) 97-98% of the climate researchers most actively publishing in the field surveyed here support the tenets of ACC outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers.

  1. Potential impact of climate change on the Intra-Americas Sea: Part-1. A dynamic downscaling of the CMIP5 model projections

    NASA Astrophysics Data System (ADS)

    Liu, Yanyun; Lee, Sang-Ki; Enfield, David B.; Muhling, Barbara A.; Lamkin, John T.; Muller-Karger, Frank E.; Roffer, Mitchell A.

    2015-08-01

    This study examines the potential impact of anthropogenic greenhouse warming on the Intra-Americas Sea (IAS, Caribbean Sea and Gulf of Mexico) by downscaling the Coupled Model Intercomparison Project phase-5 (CMIP5) model simulations under historical and two future emission scenarios using an eddy-resolving resolution regional ocean model. The simulated volume transport by the western boundary current system in the IAS, including the Caribbean Current, Yucatan Current and Loop Current (LC), is reduced by 20-25% during the 21st century, consistent with a similar rate of reduction in the Atlantic Meridional Overturning Circulation (AMOC). The effect of the LC in the present climate is to warm the Gulf of Mexico (GoM). Therefore, the reduced LC and the associated weakening of the warm transient LC eddies have a cooling impact in the GoM, particularly during boreal spring in the northern deep basin, in agreement with an earlier dynamic downscaling study. In contrast to the reduced warming in the northern deep GoM, the downscaled model predicts an intense warming in the shallow (≤ 200 m) northeastern shelf of the GoM especially during boreal summer since there is no effective mechanism to dissipate the increased surface heating. Potential implications of the regionally distinctive warming trend pattern in the GoM on the marine ecosystems and hurricane intensifications during landfall are discussed. This study also explores the effects of 20th century warming and climate variability in the IAS using the regional ocean model forced with observed surface flux fields. The main modes of sea surface temperature variability in the IAS are linked to the Atlantic Multidecadal Oscillation and a meridional dipole pattern between the GoM and Caribbean Sea. It is also shown that variability of the IAS western boundary current system in the 20th century is largely driven by wind stress curl in the Sverdrup interior and the AMOC.

  2. Is nuance possible in climate change communication?

    NASA Astrophysics Data System (ADS)

    Donner, S. D.

    2015-12-01

    One of the core challenges of climate communication is finding the balance between honestly portraying the science, with all its complexity, and effectively engaging the audience. At a time when all politics are partisan and the media measures value in clicks, complicated stories can become black-and-white. This loss of nuance is acute in tales told of cli