Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks

Saharan mineral dust exported over the tropical North Atlantic is thought to have significant impacts on regional climate and ecosystems, but limited data exist documenting past changes in long-range dust transport. This data gap limits investigations of the role of Saharan dust in past climate chan...

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Published in:Science Advances
Main Authors: Hu, S., Fedorov, A., Murray, R. W., deMenocal, P. B., Williams, Ross Hamilton, McGee, William David, Kinsley, Christopher William, Ridley, David Andrew, Tal, Irit
Other Authors: Joint Program in Oceanography/Applied Ocean Science and Engineering, Massachusetts Institute of Technology. Department of Civil and Environmental Engineering, Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Woods Hole Oceanographic Institution
Format: Article in Journal/Newspaper
Language:English
Published: American Association for the Advancement of Science (AAAS) 2016
Subjects:
Online Access:http://hdl.handle.net/1721.1/108486
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spelling ftmit:oai:dspace.mit.edu:1721.1/108486 2023-06-11T04:14:27+02:00 Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks Hu, S. Fedorov, A. Murray, R. W. deMenocal, P. B. Williams, Ross Hamilton McGee, William David Kinsley, Christopher William Ridley, David Andrew Tal, Irit Joint Program in Oceanography/Applied Ocean Science and Engineering Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Woods Hole Oceanographic Institution Williams, Ross Hamilton McGee, William David Kinsley, Christopher William Ridley, David Andrew Tal, Irit 2016-02 application/pdf http://hdl.handle.net/1721.1/108486 en_US eng American Association for the Advancement of Science (AAAS) http://dx.doi.org/10.1126/sciadv.1600445 Science Advances 2375-2548 http://hdl.handle.net/1721.1/108486 Williams, R. H. et al. “Glacial to Holocene Changes in Trans-Atlantic Saharan Dust Transport and Dust-Climate Feedbacks.” Science Advances 2.11 (2016): e1600445–e1600445. orcid:0000-0002-3819-4926 orcid:0000-0002-3185-520X orcid:0000-0003-3890-0197 Creative Commons Attribution-NonCommercial 4.0 International http://creativecommons.org/licenses/by-nc/4.0/ AAAS Article http://purl.org/eprint/type/JournalArticle 2016 ftmit https://doi.org/10.1126/sciadv.1600445 2023-05-29T08:31:26Z Saharan mineral dust exported over the tropical North Atlantic is thought to have significant impacts on regional climate and ecosystems, but limited data exist documenting past changes in long-range dust transport. This data gap limits investigations of the role of Saharan dust in past climate change, in particular during the mid-Holocene, when climate models consistently underestimate the intensification of the West African monsoon documented by paleorecords. We present reconstructions of African dust deposition in sediments from the Bahamas and the tropical North Atlantic spanning the last 23,000 years. Both sites show early and mid-Holocene dust fluxes 40 to 50% lower than recent values and maximum dust fluxes during the deglaciation, demonstrating agreement with records from the northwest African margin. These quantitative estimates of trans-Atlantic dust transport offer important constraints on past changes in dust-related radiative and biogeochemical impacts. Using idealized climate model experiments to investigate the response to reductions in Saharan dust’s radiative forcing over the tropical North Atlantic, we find that small (0.15°C) dust-related increases in regional sea surface temperatures are sufficient to cause significant northward shifts in the Atlantic Intertropical Convergence Zone, increased precipitation in the western Sahel and Sahara, and reductions in easterly and northeasterly winds over dust source regions. Our results suggest that the amplifying feedback of dust on sea surface temperatures and regional climate may be significant and that accurate simulation of dust’s radiative effects is likely essential to improving model representations of past and future precipitation variations in North Africa. National Science Foundation (U.S.) (Award OCE-1030784) United States. National Aeronautics and Space Administration (Grant NN14AP38G) Columbia University. Center for Climate and Life Article in Journal/Newspaper North Atlantic DSpace@MIT (Massachusetts Institute of Technology) Science Advances 2 11 e1600445
institution Open Polar
collection DSpace@MIT (Massachusetts Institute of Technology)
op_collection_id ftmit
language English
description Saharan mineral dust exported over the tropical North Atlantic is thought to have significant impacts on regional climate and ecosystems, but limited data exist documenting past changes in long-range dust transport. This data gap limits investigations of the role of Saharan dust in past climate change, in particular during the mid-Holocene, when climate models consistently underestimate the intensification of the West African monsoon documented by paleorecords. We present reconstructions of African dust deposition in sediments from the Bahamas and the tropical North Atlantic spanning the last 23,000 years. Both sites show early and mid-Holocene dust fluxes 40 to 50% lower than recent values and maximum dust fluxes during the deglaciation, demonstrating agreement with records from the northwest African margin. These quantitative estimates of trans-Atlantic dust transport offer important constraints on past changes in dust-related radiative and biogeochemical impacts. Using idealized climate model experiments to investigate the response to reductions in Saharan dust’s radiative forcing over the tropical North Atlantic, we find that small (0.15°C) dust-related increases in regional sea surface temperatures are sufficient to cause significant northward shifts in the Atlantic Intertropical Convergence Zone, increased precipitation in the western Sahel and Sahara, and reductions in easterly and northeasterly winds over dust source regions. Our results suggest that the amplifying feedback of dust on sea surface temperatures and regional climate may be significant and that accurate simulation of dust’s radiative effects is likely essential to improving model representations of past and future precipitation variations in North Africa. National Science Foundation (U.S.) (Award OCE-1030784) United States. National Aeronautics and Space Administration (Grant NN14AP38G) Columbia University. Center for Climate and Life
author2 Joint Program in Oceanography/Applied Ocean Science and Engineering
Massachusetts Institute of Technology. Department of Civil and Environmental Engineering
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Woods Hole Oceanographic Institution
Williams, Ross Hamilton
McGee, William David
Kinsley, Christopher William
Ridley, David Andrew
Tal, Irit
format Article in Journal/Newspaper
author Hu, S.
Fedorov, A.
Murray, R. W.
deMenocal, P. B.
Williams, Ross Hamilton
McGee, William David
Kinsley, Christopher William
Ridley, David Andrew
Tal, Irit
spellingShingle Hu, S.
Fedorov, A.
Murray, R. W.
deMenocal, P. B.
Williams, Ross Hamilton
McGee, William David
Kinsley, Christopher William
Ridley, David Andrew
Tal, Irit
Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks
author_facet Hu, S.
Fedorov, A.
Murray, R. W.
deMenocal, P. B.
Williams, Ross Hamilton
McGee, William David
Kinsley, Christopher William
Ridley, David Andrew
Tal, Irit
author_sort Hu, S.
title Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks
title_short Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks
title_full Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks
title_fullStr Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks
title_full_unstemmed Glacial to Holocene changes in trans-Atlantic Saharan dust transport and dust-climate feedbacks
title_sort glacial to holocene changes in trans-atlantic saharan dust transport and dust-climate feedbacks
publisher American Association for the Advancement of Science (AAAS)
publishDate 2016
url http://hdl.handle.net/1721.1/108486
genre North Atlantic
genre_facet North Atlantic
op_source AAAS
op_relation http://dx.doi.org/10.1126/sciadv.1600445
Science Advances
2375-2548
http://hdl.handle.net/1721.1/108486
Williams, R. H. et al. “Glacial to Holocene Changes in Trans-Atlantic Saharan Dust Transport and Dust-Climate Feedbacks.” Science Advances 2.11 (2016): e1600445–e1600445.
orcid:0000-0002-3819-4926
orcid:0000-0002-3185-520X
orcid:0000-0003-3890-0197
op_rights Creative Commons Attribution-NonCommercial 4.0 International
http://creativecommons.org/licenses/by-nc/4.0/
op_doi https://doi.org/10.1126/sciadv.1600445
container_title Science Advances
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container_issue 11
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