Consistent simulations of multiple proxy responses to an abrupt climate change event. Export

@article{citeulike:497530, abstract = {Isotope, aerosol, and methane records document an abrupt cooling event across the Northern Hemisphere at 8.2 kiloyears before present (kyr), while separate geologic lines of evidence document the catastrophic drainage of the glacial Lakes Agassiz and Ojibway into the Hudson Bay at approximately the same time. This melt water pulse may have been the catalyst for a decrease in North Atlantic Deep Water formation and subsequent cooling around the Northern Hemisphere. However, lack of direct evidence for ocean cooling has lead to speculation that this abrupt event was purely local to Greenland and called into question this proposed mechanism. We simulate the response to this melt water pulse using a coupled general circulation model that explicitly tracks water isotopes and with atmosphere-only experiments that calculate changes in atmospheric aerosol deposition (specifically (10)Be and dust) and wetland methane emissions. The simulations produce a short period of significantly diminished North Atlantic Deep Water and are able to quantitatively match paleoclimate observations, including the lack of isotopic signal in the North Atlantic. This direct comparison with multiple proxy records provides compelling evidence that changes in ocean circulation played a major role in this abrupt climate change event.}, address = {National Aeronautics and Space Administration Goddard Institute for Space Studies and Center for Climate Systems Research, Columbia University, New York, NY 10025.}, author = {Legrande, A. N. and Schmidt, G. A. and Shindell, D. T. and Field, C. V. and Miller, R. L. and Koch, D. M. and Faluvegi, G. and Hoffmann, G.}, citeulike-article-id = {497530}, citeulike-linkout-0 = {http://dx.doi.org/10.1073/pnas.0510095103}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/16415159}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=16415159}, comment = {"changes in ocean circulation played a major role in this abrupt climate change event."}, day = {24}, doi = {10.1073/pnas.0510095103}, issn = {0027-8424}, journal = {Proc Natl Acad Sci U S A}, keywords = {05matheco30\_theoretic, cat\_envorinmental\_sciences, north\_atlantic\_deep\_water, paleoclimate}, month = {January}, number = {4}, pages = {837--842}, posted-at = {2006-02-08 03:27:16}, priority = {2}, title = {Consistent simulations of multiple proxy responses to an abrupt climate change event.}, url = {http://dx.doi.org/10.1073/pnas.0510095103}, volume = {103}, year = {2006} }

TY - JOUR ID - citeulike:497530 L3 - citeulike-article-id:497530 N2 - Isotope, aerosol, and methane records document an abrupt cooling event across the Northern Hemisphere at 8.2 kiloyears before present (kyr), while separate geologic lines of evidence document the catastrophic drainage of the glacial Lakes Agassiz and Ojibway into the Hudson Bay at approximately the same time. This melt water pulse may have been the catalyst for a decrease in North Atlantic Deep Water formation and subsequent cooling around the Northern Hemisphere. However, lack of direct evidence for ocean cooling has lead to speculation that this abrupt event was purely local to Greenland and called into question this proposed mechanism. We simulate the response to this melt water pulse using a coupled general circulation model that explicitly tracks water isotopes and with atmosphere-only experiments that calculate changes in atmospheric aerosol deposition (specifically (10)Be and dust) and wetland methane emissions. The simulations produce a short period of significantly diminished North Atlantic Deep Water and are able to quantitatively match paleoclimate observations, including the lack of isotopic signal in the North Atlantic. This direct comparison with multiple proxy records provides compelling evidence that changes in ocean circulation played a major role in this abrupt climate change event. IS - 4 JF - Proc Natl Acad Sci U S A SN - 0027-8424 AD - National Aeronautics and Space Administration Goddard Institute for Space Studies and Center for Climate Systems Research, Columbia University, New York, NY 10025. EP - 842 TI - Consistent simulations of multiple proxy responses to an abrupt climate change event. VL - 103 SP - 837 KW - 05matheco30_theoretic KW - cat_envorinmental_sciences KW - north_atlantic_deep_water KW - paleoclimate N1 - "changes in ocean circulation played a major role in this abrupt climate change event." AU - Legrande, AN AU - Schmidt, GA AU - Shindell, DT AU - Field, CV AU - Miller, RL AU - Koch, DM AU - Faluvegi, G AU - Hoffmann, G PY - 2006/01/24/ UR - http://dx.doi.org/10.1073/pnas.0510095103 ER -