ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Antarctic Regions  (2)
Collection
Keywords
Publisher
Years
  • 1
    facet.materialart.
    Unknown
    Glacial greenhouse-gas fluctuations controlled by ocean circulation changes (2008)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2008-11-21
    Description: Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO(2)) and nitrous oxide (N(2)O) varied strongly on millennial timescales during past glacial periods. Large and rapid warming events in Greenland and the North Atlantic were followed by more gradual cooling, and are highly correlated with fluctuations of N(2)O as recorded in ice cores. Antarctic temperature variations, on the other hand, were smaller and more gradual, showed warming during the Greenland cold phase and cooling while the North Atlantic was warm, and were highly correlated with fluctuations in CO(2). Abrupt changes in the Atlantic meridional overturning circulation (AMOC) have often been invoked to explain the physical characteristics of these Dansgaard-Oeschger climate oscillations, but the mechanisms for the greenhouse-gas variations and their linkage to the AMOC have remained unclear. Here we present simulations with a coupled model of glacial climate and biogeochemical cycles, forced only with changes in the AMOC. The model simultaneously reproduces characteristic features of the Dansgaard-Oeschger temperature, as well as CO(2) and N(2)O fluctuations. Despite significant changes in the land carbon inventory, CO(2) variations on millennial timescales are dominated by slow changes in the deep ocean inventory of biologically sequestered carbon and are correlated with Antarctic temperature and Southern Ocean stratification. In contrast, N(2)O co-varies more rapidly with Greenland temperatures owing to fast adjustments of the thermocline oxygen budget. These results suggest that ocean circulation changes were the primary mechanism that drove glacial CO(2) and N(2)O fluctuations on millennial timescales.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Schmittner, Andreas -- Galbraith, Eric D -- England -- Nature. 2008 Nov 20;456(7220):373-6. doi: 10.1038/nature07531.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉College of Oceanic & Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, USA. aschmitt@coas.oregonstate.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19020618" target="_blank"〉PubMed〈/a〉
    Keywords: Antarctic Regions ; Arctic Regions ; Atlantic Ocean ; Carbon Dioxide/analysis ; Ecosystem ; *Greenhouse Effect ; Greenland ; History, Ancient ; Ice Cover/*chemistry ; Models, Theoretical ; Nitrous Oxide/analysis ; Phytoplankton/metabolism ; Seawater/*chemistry ; *Water Movements
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation (2012)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2012-04-07
    Description: The covariation of carbon dioxide (CO(2)) concentration and temperature in Antarctic ice-core records suggests a close link between CO(2) and climate during the Pleistocene ice ages. The role and relative importance of CO(2) in producing these climate changes remains unclear, however, in part because the ice-core deuterium record reflects local rather than global temperature. Here we construct a record of global surface temperature from 80 proxy records and show that temperature is correlated with and generally lags CO(2) during the last (that is, the most recent) deglaciation. Differences between the respective temperature changes of the Northern Hemisphere and Southern Hemisphere parallel variations in the strength of the Atlantic meridional overturning circulation recorded in marine sediments. These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO(2) concentrations is an explanation for much of the temperature change at the end of the most recent ice age.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Shakun, Jeremy D -- Clark, Peter U -- He, Feng -- Marcott, Shaun A -- Mix, Alan C -- Liu, Zhengyu -- Otto-Bliesner, Bette -- Schmittner, Andreas -- Bard, Edouard -- England -- Nature. 2012 Apr 4;484(7392):49-54. doi: 10.1038/nature10915.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA. shakun@fas.harvard.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22481357" target="_blank"〉PubMed〈/a〉
    Keywords: Antarctic Regions ; Atmosphere/chemistry ; Carbon Dioxide/*analysis ; Fossils ; Geography ; Geologic Sediments/chemistry ; Global Warming/*statistics & numerical data ; Greenland ; History, Ancient ; *Ice Cover ; Models, Theoretical ; Monte Carlo Method ; Pollen ; Seawater/analysis ; *Temperature ; Uncertainty
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...