Polarized Response of East Asian Winter Temperature Extremes in the Era of Arctic Warming

AbstractIt has been argued that fewer cold extremes will be expected to occur over most mid–latitude areas, due to anthropogenic-induced global warming. However, East Asia repeatedly suffered from unexpected cold spells during the winter of 2015/2016, and the low surface air temperature (SAT) during January 21–25, 2016 broke the previous calendar record from 1961. We hypothesize that cold extremes such as these occur due to Arctic Amplification (AA) of global warming. To test this hypothesis, we analyzed the changes of SAT variability in the winter season over East Asia. Our results show that the SAT variability (measured by the standard deviation of the winter season daily mean SAT) over East Asia has significantly increased in the era of AA during 1988/1989-2015/2016, and exhibits a polarization between warm and cold extremes, popularly dubbed as “weather whiplash”. This phenomenon is driven by both the thermodynamic effects of global warming and the dynamic effects of AA. Global warming favors a rising...