Slowdown of Antarctic Bottom Water export driven by climatic wind and sea ice changes ...

• Main Authors: Zhou, Shenjie, Meijers, Andrew, Meredith, Michael, Abrahamsen, Povl, Holland, Paul, Silvano, Alessandro, Sallée, Jean-baptiste, Østerhus, Svein
• Format: Conference Object
• Language: unknown
• Published: GFZ German Research Centre for Geosciences 2023
• Subjects: Antarctic; Weddell; Weddell Sea; Antarc*; Sea ice
• Online Access: https://dx.doi.org/10.57757/iugg23-0821; https://gfzpublic.gfz-potsdam.de/pubman/item/item_5016660

<!--!introduction!--> Antarctic Bottom Water (AABW) is a key water mass in the global overturning circulation, flooding most of the world ocean abyss and pivotal for deep ocean ventilation and oceanic heat and carbon exchanges on multi-decadal to millennial timescales. The Weddell Sea contributes nearly half of global AABW through Weddell Sea Deep Water (WSDW), which along with denser underlying Weddell Sea Bottom Water (WSBW), is formed on the continental shelves via complex processes that include sea ice production. Here we report a multi-decadal decline of WSBW volume in repeat hydrographic sections. A 30% reduction of WSBW volume since 1992 is found, with the most significant volume decrease seen in the densest WSBW classes. This is likely driven by a multi-decadal reduction in dense water production on the Weddell Sea continental shelf associated with a >40% decline in the sea ice formation rate there. The ice production decrease is driven by northerly wind trends, partly in response to a ... : The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) ...