Amplified Waveguide Teleconnections Along the Polar Front Jet Favor Summer Temperature Extremes Over Northern Eurasia
Peiqiang Xu, Lin Wang, Geoffrey K. Vallis, Ruth Geen, James A. Screen, Peili Wu, Shuoyi Ding, Ping Huang, Wen Chen
Abstract
Abstract An apparent increase in the frequency of summer temperature extremes over northern Eurasia has been observed in the past decade. Some of these high‐impact events were associated with amplified waveguide teleconnections embedded in the polar front jet, but it remains unclear if extreme temperatures are robustly and routinely related to amplified waves along the polar front jet. This study systematically examines relationships between planetary wave activity and temperature extremes using observations, reanalysis, and large‐ensemble simulations from multiple climate models. Months with extreme temperatures over northern Eurasia generally have amplified wave activity along the polar front jet, whereas months with near‐average temperatures tend to have attenuated wave activity. Waveguide teleconnections are particularly amplified during extremely hot and cold summer months over eastern Europe and western Russia. These findings demonstrate the important role of waveguide teleconnections along the polar front jet in generating regional temperature extremes over northern Eurasia.