Skip to Main content Skip to Navigation
Journal articles

Impacts of Arctic sea ice on cold season atmospheric variability and trends estimated from observations and a multi-model large ensemble

Abstract : To examine the atmospheric responses to Arctic sea-ice variability in the Northern Hemisphere cold season (October to following March), this study uses a coordinated set of large-ensemble experiments of nine atmospheric general circulation models (AGCMs) forced with observed daily-varying sea-ice, sea-surface temperature, and radiative forcings prescribed during the 1979-2014 period, together with a parallel set of experiments where Arctic sea ice is substituted by its climatology. The simulations of the former set reproduce the near-surface temperature trends in reanalysis data, with similar amplitude, and their multi-model ensemble mean (MMEM) shows decreasing sea-level pressure over much of the polar cap and Eurasia in boreal autumn. The MMEM difference between the two experiments allows isolating the effects of Arctic sea-ice loss, which explain a large portion of the Arctic warming trends in the lower troposphere and drives a small but statistically significant weakening of the wintertime Arctic Oscillation. The observed interannual co-variability between sea-ice extent in the Barents-Kara Seas and lagged atmospheric circulation is distinguished from the effects of confounding factors based on multiple regression, and quantitatively compared to the co-variability in MMEMs. The interannual sea-ice decline followed by a negative North Atlantic Oscillation-like anomaly found in observations is also seen in the MMEM differences, with consistent spatial structure but much smaller amplitude. This result suggests that the sea-ice impacts on trends and interannual atmospheric variability simulated by AGCMs could be underestimated, but caution is needed because internal atmospheric variability may have affected the observed relationship.
Document type :
Journal articles
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-03608156
Contributor : Françoise Pinsard Connect in order to contact the contributor
Submitted on : Monday, August 8, 2022 - 3:02:26 PM
Last modification on : Tuesday, August 9, 2022 - 3:02:32 AM

File

[15200442 - Journal of Climate...
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Yu-Chiao Liang, Claude Frankignoul, Young-Oh Kwon, Guillaume Gastineau, Elisa Manzini, et al.. Impacts of Arctic sea ice on cold season atmospheric variability and trends estimated from observations and a multi-model large ensemble. Journal of Climate, American Meteorological Society, 2021, 34 (20), pp.8419-8443. ⟨10.1175/JCLI-D-20-0578.1⟩. ⟨hal-03608156⟩

Share

Metrics

Record views

22

Files downloads

0