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Title: Persistent Ross Sea Freshening From Imbalance West Antarctic Ice Shelf Melting
Abstract

A 63‐year observational record in the southwest Ross Sea shows a continuing, near‐linear salinity decrease of 0.170 and slight warming of 0.013°C through 2020. That freshening exceeded any increase in sea ice production and brine release from stronger southerly winds, while melting and freezing at the Ross Ice Shelf base contributed little to the salinity change. The parallel seawater density decline appears not to have enhanced warm deep water intrusions onto the continental shelf (CS). Confirming prior inferences, the salinity change has been mainly caused by a growing imbalance in the meltwater available from thinning ice shelves and increased iceberg calving in the upstream Amundsen and Bellingshausen Seas. Shorter‐term salinity variability has tracked winds near the Amundsen Sea CS break, in turn coherent with a broader Pacific climate variability index, and with salinity reversals on and seaward of the Ross CS. The melt driven freshening is positively correlated with global atmospheric CO2and temperature increases, and adds to the rise in sea level from increased glacier flow into weakened ice shelves. Continued erosion of those ice shelves could end the production of high salinity shelf and bottom waters, as defined in the Ross Sea, by the 2050s.

 
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PAR ID:
10375705
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Geophysical Research: Oceans
Volume:
127
Issue:
3
ISSN:
2169-9275
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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