Role of the Antarctic Circumpolar Circulation in Current Asymmetric Arctic and Antarctic Warming

Abstract Both historical observations and recent modeling studies reveal a faster warming in the Arctic compared to the Antarctic. To understand the role of the Antarctic Circumpolar Circulation (ACC) in this warming asymmetry, we simulate the climate mean state and climate response to doubled CO2 u...

Full description

Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Peixi Wang, Song Yang, Zhenning Li, Zhaoyang Song, Xichen Li, Xiaoming Hu
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2024
Subjects:
Online Access:https://doi.org/10.1029/2024GL110265
https://doaj.org/article/b1ec60f073b04ef2846a206a70de84aa
Description
Summary:Abstract Both historical observations and recent modeling studies reveal a faster warming in the Arctic compared to the Antarctic. To understand the role of the Antarctic Circumpolar Circulation (ACC) in this warming asymmetry, we simulate the climate mean state and climate response to doubled CO2 under different climate mean ACC states by closing or opening the Drake Passage (DP) with the Community Earth System Model. From closed to open DP, a stronger climate mean ACC leads to a stronger climate mean Atlantic Meridional Overturning Circulation (AMOC), as well as a colder Antarctic but a warmer Arctic in the climate mean state. The less climate mean sea ice coverage in a warmer Arctic implies less extensive sea ice melting under global warming. This causes a reduced asymmetry in warming between the two poles in response to the doubled CO2.