Work

Stratospheric variability contributed to and sustained the recent hiatus in Eurasian winter warming

Year: 2016

Type: article

Abstract: The recent hiatus in global-mean surface temperature warming was characterized by a Eurasian winter cooling trend, and the cause(s) for this cooling is unclear. Here we show that the observed hiatus in Eurasian warming was associated with a recent trend toward weakened stratospheric polar vortices. Specifically, by calculating the change in Eurasian surface air temperature associated with a given vortex weakening, we demonstrate that the recent trend toward weakened polar vortices reduced the anticipated Eurasian warming due to increasing greenhouse gas concentrations. Those model integrations whose stratospheric vortex evolution most closely matches that in reanalysis data also simulate a hiatus. While it is unclear whether the recent weakening of the midwinter stratospheric polar vortex was forced, a properly configured model can simulate substantial deviations of the polar vortex on decadal timescales and hence such hiatus events, implying that similar hiatus events may recur even as greenhouse gas concentrations rise.

Source: Geophysical Research Letters

DOI: 10.1002/2016gl072035

Authors: Chaim I. Garfinkel, Seok‐Woo Son, Kanghyun Song, Valentina Aquila, Luke D. Oman

Institutions: Hebrew University of Jerusalem, Seoul National University, Johns Hopkins University, Goddard Space Flight Center

Language: English

Topic: Climate variability and models

Subfield: Global and Planetary Change

Field: Environmental Science

Domain: Physical Sciences

SDG: Climate action

Open Access status: hybrid

Estimated APC paid: $3,190