Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka
We compared four simulations of the 8.2 ka event to assess climate model sensitivity and skill in responding to North Atlantic freshwater perturbations. All of the simulations used the same freshwater forcing, 2.5 Sv for one year, applied to either the Hudson Bay (northeastern Canada) or Labrador Se...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20140016854 2023-05-15T16:29:09+02:00 Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka Legrande, Allegra Nicole Bakker, P. Otto-Bliesner, B. L. Morrill, Carrie Renssen, H. Unclassified, Unlimited, Publicly available April 10, 2013 application/pdf http://hdl.handle.net/2060/20140016854 unknown Document ID: 20140016854 http://hdl.handle.net/2060/20140016854 Copyright, Distribution as joint owner in the copyright CASI Meteorology and Climatology GSFC-E-DAA-TN15444 Climate of the Past; 9; 2; 955-968 2013 ftnasantrs 2019-07-21T00:22:03Z We compared four simulations of the 8.2 ka event to assess climate model sensitivity and skill in responding to North Atlantic freshwater perturbations. All of the simulations used the same freshwater forcing, 2.5 Sv for one year, applied to either the Hudson Bay (northeastern Canada) or Labrador Sea (between Canada's Labrador coast and Greenland). This freshwater pulse induced a decadal-mean slowdown of 10-25%in the Atlantic Meridional Overturning Circulation (AMOC) of the models and caused a large-scale pattern of climate anomalies that matched proxy evidence for cooling in the Northern Hemisphere and a southward shift of the Intertropical Convergence Zone. The multi-model ensemble generated temperature anomalies that were just half as large as those from quantitative proxy reconstructions, however. Also, the duration of AMOC and climate anomalies in three of the simulations was only several decades, significantly shorter than the duration of approx.150 yr in the paleoclimate record. Possible reasons for these discrepancies include incorrect representation of the early Holocene climate and ocean state in the North Atlantic and uncertainties in the freshwater forcing estimates. Other/Unknown Material Greenland Hudson Bay Labrador Sea North Atlantic NASA Technical Reports Server (NTRS) Canada Greenland Hudson Hudson Bay |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
Meteorology and Climatology |
spellingShingle |
Meteorology and Climatology Legrande, Allegra Nicole Bakker, P. Otto-Bliesner, B. L. Morrill, Carrie Renssen, H. Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka |
topic_facet |
Meteorology and Climatology |
description |
We compared four simulations of the 8.2 ka event to assess climate model sensitivity and skill in responding to North Atlantic freshwater perturbations. All of the simulations used the same freshwater forcing, 2.5 Sv for one year, applied to either the Hudson Bay (northeastern Canada) or Labrador Sea (between Canada's Labrador coast and Greenland). This freshwater pulse induced a decadal-mean slowdown of 10-25%in the Atlantic Meridional Overturning Circulation (AMOC) of the models and caused a large-scale pattern of climate anomalies that matched proxy evidence for cooling in the Northern Hemisphere and a southward shift of the Intertropical Convergence Zone. The multi-model ensemble generated temperature anomalies that were just half as large as those from quantitative proxy reconstructions, however. Also, the duration of AMOC and climate anomalies in three of the simulations was only several decades, significantly shorter than the duration of approx.150 yr in the paleoclimate record. Possible reasons for these discrepancies include incorrect representation of the early Holocene climate and ocean state in the North Atlantic and uncertainties in the freshwater forcing estimates. |
format |
Other/Unknown Material |
author |
Legrande, Allegra Nicole Bakker, P. Otto-Bliesner, B. L. Morrill, Carrie Renssen, H. |
author_facet |
Legrande, Allegra Nicole Bakker, P. Otto-Bliesner, B. L. Morrill, Carrie Renssen, H. |
author_sort |
Legrande, Allegra Nicole |
title |
Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka |
title_short |
Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka |
title_full |
Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka |
title_fullStr |
Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka |
title_full_unstemmed |
Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka |
title_sort |
model sensitivity to north atlantic freshwater forcing at 8.2 ka |
publishDate |
2013 |
url |
http://hdl.handle.net/2060/20140016854 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Canada Greenland Hudson Hudson Bay |
geographic_facet |
Canada Greenland Hudson Hudson Bay |
genre |
Greenland Hudson Bay Labrador Sea North Atlantic |
genre_facet |
Greenland Hudson Bay Labrador Sea North Atlantic |
op_source |
CASI |
op_relation |
Document ID: 20140016854 http://hdl.handle.net/2060/20140016854 |
op_rights |
Copyright, Distribution as joint owner in the copyright |
_version_ |
1766018845348200448 |