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This content will become publicly available on May 1, 2026

Title: Distinct Impacts of Multiyear El Niño on Antarctic Sea Ice Concentration due to Atlantic and Indian Ocean Conditions
Abstract This study explores the Antarctic sea ice concentration (SIC) response to multiyear (MY) and single-year (SY) El Niños using a 2200-yr CESM1 preindustrial simulation. During the first austral winter, MY El Niño weakens the amplitude of the typical SIC anomaly pattern induced by SY El Niño but maintains the same impact pattern. During the second winter, MY El Niños not only intensify the amplitude but also shift the typical impact pattern of SY El Niños eastward. The amplitude variation effect on SIC is caused by an Indian Ocean memory mechanism, while the zonal shifting effect on SIC pattern is caused by an Atlantic Ocean memory mechanism. These mechanisms result from the different responses of the two oceans to different locations and intensities between SY and MY El Niños. Observed MY El Niños during 1979–2020 confirm the distinct impacts during the second austral winter revealed by the CESM1 simulation. These results demonstrate that SIC in the Ross and Amundsen–Bellingshausen–Weddell Seas is sensitive to the SY or MY types of El Niño.  more » « less
Award ID(s):
2109539
PAR ID:
10644552
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
American Meteorological Society
Date Published:
Journal Name:
Journal of Climate
Volume:
38
Issue:
9
ISSN:
0894-8755
Page Range / eLocation ID:
2063 to 2077
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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