Investigation of the mechanism that the decline of Arctic sea-ice causes meandering of westerly wind

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K17758
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: The University of Tokyo
• Principal Investigator: Mori Masato 東京大学, 先端科学技術研究センター, 助教 (00749179)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 北極 / 海氷 / 異常気象 / アンサンブルシミュレーション

Outline of Final Research Achievements

Rapid reduction of Arctic sea ice is prominent with the progress of global warming. We investigated influence of the sea-ice loss on the extreme cold winter in mid-latitude through meandering of westerly wind and its mechanism.
Analysis of large ensemble simulations performed by several atmospheric global circulation models (AGCMs) and diagnosis by linear baroclinic model showed following things; (1) The Arctic sea ice loss increases the occurrence frequency of extremely cold winter in the east Asia through excitation of WACE pattern that represents the meandering of westerly wind at the upper troposphere, (2) but these features are not well reproduced in the AGCMs. (3) This suggests the importance of atmosphere-ocean interaction to accurately estimate the impact of Arctic sea-ice loss on the mid-latitude.

Free Research Field

気象学