COLLOQUIUM: Effects of a Rapidly Warming Arctic on Weather Patterns in Mid-Latitudes

*** PLEASE NOTE EARLIER TIME OF 3:00PM ***

In this presentation I will build on the study presented in Francis and Vavrus (GRL, 2012) in which mechanisms were proposed and demonstrated that link enhanced warming in the Arctic during recent decades with changes in weather patterns in mid-latitudes. Evidence suggests Arctic Amplification may have contributed to an increase in large-scale wave amplitude and slower zonal upper-level winds, both of which favor more persistent weather patterns in mid-latitudes. Prolonged weather conditions are often associated with extreme weather -- such as droughts, cold spells, heat waves, and some flooding events -- some of which appear to be increasing in frequency. New analysis of fields from reanalyses and climate-model output will be presented that illustrates the response of mid-latitude upper-level flow characteristics to Arctic Amplification.