Southern Ocean warming delayed by circumpolar upwelling and equatorward transport
The Southern Ocean has shown little warming over recent decades, in stark contrast to the rapid warming observed in the Arctic. Along the northern flank of the Antarctic Circumpolar Current, however, the upper ocean has warmed substantially. Here we present analyses of oceanographic observations and...
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ftmit:oai:dspace.mit.edu:1721.1/106534 2023-06-11T04:05:20+02:00 Southern Ocean warming delayed by circumpolar upwelling and equatorward transport Armour, Kyle C. Donohoe, Aaron Newsom, Emily R. Marshall, John C Scott, Jeffery R Massachusetts Institute of Technology. Center for Global Change Science Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Marshall, John C Scott, Jeffery R 2016-02 application/pdf http://hdl.handle.net/1721.1/106534 en_US eng Nature Publishing Group http://dx.doi.org/10.1038/ngeo2731 Nature Geoscience 1752-0894 1752-0908 http://hdl.handle.net/1721.1/106534 Armour, Kyle C., John Marshall, Jeffery R. Scott, Aaron Donohoe, and Emily R. Newsom. “Southern Ocean Warming Delayed by Circumpolar Upwelling and Equatorward Transport.” Nature Geoscience, vol. 9, no. 7, 2016, pp. 549–554. orcid:0000-0001-9230-3591 Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ MIT Web Domain Article http://purl.org/eprint/type/JournalArticle 2016 ftmit https://doi.org/10.1038/ngeo2731 2023-05-29T08:48:49Z The Southern Ocean has shown little warming over recent decades, in stark contrast to the rapid warming observed in the Arctic. Along the northern flank of the Antarctic Circumpolar Current, however, the upper ocean has warmed substantially. Here we present analyses of oceanographic observations and general circulation model simulations showing that these patterns—of delayed warming south of the Antarctic Circumpolar Current and enhanced warming to the north—are fundamentally shaped by the Southern Ocean’s meridional overturning circulation: wind-driven upwelling of unmodified water from depth damps warming around Antarctica; greenhouse gas-induced surface heat uptake is largely balanced by anomalous northward heat transport associated with the equatorward flow of surface waters; and heat is preferentially stored where surface waters are subducted to the north. Further, these processes are primarily due to passive advection of the anomalous warming signal by climatological ocean currents; changes in ocean circulation are secondary. These findings suggest the Southern Ocean responds to greenhouse gas forcing on the centennial, or longer, timescale over which the deep ocean waters that are upwelled to the surface are warmed themselves. It is against this background of gradual warming that multidecadal Southern Ocean temperature trends must be understood. National Science Foundation (U.S.) (grant OCE-1259388) National Science Foundation (U.S.) (grant OCE-1338814) National Science Foundation (U.S.) (grant OCE-1523641) National Science Foundation (U.S.) (grant PLR-1341497) United States. National Aeronautics and Space Administration (award NNX11AL79G) Article in Journal/Newspaper Antarc* Antarctic Antarctica Arctic Southern Ocean DSpace@MIT (Massachusetts Institute of Technology) Arctic Antarctic Southern Ocean The Antarctic Nature Geoscience 9 7 549 554 |
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English |
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The Southern Ocean has shown little warming over recent decades, in stark contrast to the rapid warming observed in the Arctic. Along the northern flank of the Antarctic Circumpolar Current, however, the upper ocean has warmed substantially. Here we present analyses of oceanographic observations and general circulation model simulations showing that these patterns—of delayed warming south of the Antarctic Circumpolar Current and enhanced warming to the north—are fundamentally shaped by the Southern Ocean’s meridional overturning circulation: wind-driven upwelling of unmodified water from depth damps warming around Antarctica; greenhouse gas-induced surface heat uptake is largely balanced by anomalous northward heat transport associated with the equatorward flow of surface waters; and heat is preferentially stored where surface waters are subducted to the north. Further, these processes are primarily due to passive advection of the anomalous warming signal by climatological ocean currents; changes in ocean circulation are secondary. These findings suggest the Southern Ocean responds to greenhouse gas forcing on the centennial, or longer, timescale over which the deep ocean waters that are upwelled to the surface are warmed themselves. It is against this background of gradual warming that multidecadal Southern Ocean temperature trends must be understood. National Science Foundation (U.S.) (grant OCE-1259388) National Science Foundation (U.S.) (grant OCE-1338814) National Science Foundation (U.S.) (grant OCE-1523641) National Science Foundation (U.S.) (grant PLR-1341497) United States. National Aeronautics and Space Administration (award NNX11AL79G) |
author2 |
Massachusetts Institute of Technology. Center for Global Change Science Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Marshall, John C Scott, Jeffery R |
format |
Article in Journal/Newspaper |
author |
Armour, Kyle C. Donohoe, Aaron Newsom, Emily R. Marshall, John C Scott, Jeffery R |
spellingShingle |
Armour, Kyle C. Donohoe, Aaron Newsom, Emily R. Marshall, John C Scott, Jeffery R Southern Ocean warming delayed by circumpolar upwelling and equatorward transport |
author_facet |
Armour, Kyle C. Donohoe, Aaron Newsom, Emily R. Marshall, John C Scott, Jeffery R |
author_sort |
Armour, Kyle C. |
title |
Southern Ocean warming delayed by circumpolar upwelling and equatorward transport |
title_short |
Southern Ocean warming delayed by circumpolar upwelling and equatorward transport |
title_full |
Southern Ocean warming delayed by circumpolar upwelling and equatorward transport |
title_fullStr |
Southern Ocean warming delayed by circumpolar upwelling and equatorward transport |
title_full_unstemmed |
Southern Ocean warming delayed by circumpolar upwelling and equatorward transport |
title_sort |
southern ocean warming delayed by circumpolar upwelling and equatorward transport |
publisher |
Nature Publishing Group |
publishDate |
2016 |
url |
http://hdl.handle.net/1721.1/106534 |
geographic |
Arctic Antarctic Southern Ocean The Antarctic |
geographic_facet |
Arctic Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Antarctica Arctic Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica Arctic Southern Ocean |
op_source |
MIT Web Domain |
op_relation |
http://dx.doi.org/10.1038/ngeo2731 Nature Geoscience 1752-0894 1752-0908 http://hdl.handle.net/1721.1/106534 Armour, Kyle C., John Marshall, Jeffery R. Scott, Aaron Donohoe, and Emily R. Newsom. “Southern Ocean Warming Delayed by Circumpolar Upwelling and Equatorward Transport.” Nature Geoscience, vol. 9, no. 7, 2016, pp. 549–554. orcid:0000-0001-9230-3591 |
op_rights |
Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ |
op_doi |
https://doi.org/10.1038/ngeo2731 |
container_title |
Nature Geoscience |
container_volume |
9 |
container_issue |
7 |
container_start_page |
549 |
op_container_end_page |
554 |
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1768374523146534912 |