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Source
Science. 2005 Oct 21;310(5747):456-60
Publication Type
Article
Date
Oct-21-2005
Author
Alley Richard B
Clark Peter U
Huybrechts Philippe
Joughin Ian
Author Affiliation
Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, Deike Building, University Park, PA 16802, USA. rba6@psu.edu
Source
Science. 2005 Oct 21;310(5747):456-60
Date
Oct-21-2005
Language
English
Publication Type
Article
Abstract
Future sea-level rise is an important issue related to the continuing buildup of atmospheric greenhouse gas concentrations. The Greenland and Antarctic ice sheets, with the potential to raise sea level approximately 70 meters if completely melted, dominate uncertainties in projected sea-level change. Freshwater fluxes from these ice sheets also may affect oceanic circulation, contributing to climate change. Observational and modeling advances have reduced many uncertainties related to ice-sheet behavior, but recently detected, rapid ice-marginal changes contributing to sea-level rise may indicate greater ice-sheet sensitivity to warming than previously considered.
PubMed ID
16239468 View in PubMed
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Implications of abrupt climate change.

https://arctichealth.org/en/permalink/ahliterature95699
Source
Trans Am Clin Climatol Assoc. 2004;115:305-17
Publication Type
Article
Date
2004
Author
Alley Richard B
Author Affiliation
Department of Geosciences and EMS Environment Institute, Pennsylvania State University, Pennsylvania 16802, USA. ralleyo@essc.psu.edu
Source
Trans Am Clin Climatol Assoc. 2004;115:305-17
Date
2004
Language
English
Publication Type
Article
Keywords
Climate
Ecosystem
Greenhouse Effect
Humans
International Agencies
Models, Biological
Time Factors
Abstract
Records of past climates contained in ice cores, ocean sediments, and other archives show that large, abrupt, widespread climate changes have occurred repeatedly in the past. These changes were especially prominent during the cooling into and warming out of the last ice age, but persisted into the modern warm interval. Changes have especially affected water availability in warm regions and temperature in cold regions, but have affected almost all climatic variables across much or all of the Earth. Impacts of climate changes are smaller if the changes are slower or more-expected. The rapidity of abrupt climate changes, together with the difficulty of predicting such changes, means that impacts on the health of humans, economies and ecosystems will be larger if abrupt climate changes occur. Most projections of future climate include only gradual changes, whereas paleoclimatic data plus models indicate that abrupt changes remain possible; thus, policy is being made based on a view of the future that may be optimistic.
PubMed ID
17060975 View in PubMed
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Palaeoclimatic insights into future climate challenges.

https://arctichealth.org/en/permalink/ahliterature95887
Source
Philos Transact A Math Phys Eng Sci. 2003 Sep 15;361(1810):1831-48; discussion 1848-9
Publication Type
Article
Date
Sep-15-2003
Author
Alley Richard B
Author Affiliation
Department of Geosciences, The Pennsylvania State University, 517 Deike Building, University Park, PA 16802, USA. ralley@essc.psu.edu
Source
Philos Transact A Math Phys Eng Sci. 2003 Sep 15;361(1810):1831-48; discussion 1848-9
Date
Sep-15-2003
Language
English
Publication Type
Article
Keywords
Arctic Regions
Carbon Dioxide - analysis
Climate
Computer simulation
Evolution, Planetary
Greenhouse Effect
Models, Theoretical
Oceans and Seas
Paleontology - methods - trends
Sensitivity and specificity
Temperature
Abstract
Palaeoclimatic data document a sensitive climate system subject to large and perhaps difficult-to-predict abrupt changes. These data suggest that neither the sensitivity nor the variability of the climate are fully captured in some climate-change projections, such as the Intergovernmental Panel on Climate Change (IPCC) Summary for Policymakers. Because larger, faster and less-expected climate changes can cause more problems for economies and ecosystems, the palaeoclimatic data suggest the hypothesis that the future may be more challenging than anticipated in ongoing policy making. Large changes have occurred repeatedly with little net forcing. Increasing carbon dioxide concentration appears to have globalized deglacial warming, with climate sensitivity near the upper end of values from general circulation models (GCMs) used to project human-enhanced greenhouse warming; data from the warm Cretaceous period suggest a similarly high climate sensitivity to CO(2). Abrupt climate changes of the most recent glacial-interglacial cycle occurred during warm as well as cold times, linked especially to changing North Atlantic freshwater fluxes. GCMs typically project greenhouse-gas-induced North Atlantic freshening and circulation changes with notable but not extreme consequences; however, such models often underestimate the magnitude, speed or extent of past changes. Targeted research to assess model uncertainties would help to test these hypotheses.
PubMed ID
14558897 View in PubMed
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Paleoclimatic evidence for future ice-sheet instability and rapid sea-level rise.

https://arctichealth.org/en/permalink/ahliterature95742
Source
Science. 2006 Mar 24;311(5768):1747-50
Publication Type
Article
Date
Mar-24-2006
Author
Overpeck Jonathan T
Otto-Bliesner Bette L
Miller Gifford H
Muhs Daniel R
Alley Richard B
Kiehl Jeffrey T
Author Affiliation
Institute for the Study of Planet Earth, Department of Geosciences, and Department of Atmospheric Sciences, University of Arizona, Tucson, AZ 85721, USA. jto@u.arizona.edu
Source
Science. 2006 Mar 24;311(5768):1747-50
Date
Mar-24-2006
Language
English
Publication Type
Article
Abstract
Sea-level rise from melting of polar ice sheets is one of the largest potential threats of future climate change. Polar warming by the year 2100 may reach levels similar to those of 130,000 to 127,000 years ago that were associated with sea levels several meters above modern levels; both the Greenland Ice Sheet and portions of the Antarctic Ice Sheet may be vulnerable. The record of past ice-sheet melting indicates that the rate of future melting and related sea-level rise could be faster than widely thought.
Notes
Comment In: Science. 2006 Aug 25;313(5790):1043-5; author reply 1043-516931738
PubMed ID
16556837 View in PubMed
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