2018 Articles

An Intensified Mode of Variability Modulating the Summer Heat Waves in Eastern Europe and Northern China

Deng, Kaiqiang; Yang, Song; Ting, Mingfang; Lin, Ailan; Wang, Ziqian

This study investigates the leading pattern of Eurasian summer heat waves (HWs) using observed and simulated data sets and reveals an intensified mode of variability that bridges the HWs in eastern Europe (EE) and northern China (NC). The concurrent variability of the HWs in EE and NC is primarily driven by an atmospheric circum-global teleconnection that induces anomalous anticyclones over the two regions. The observed upward trends in EE and NC HW days could be related to the warm sea surface temperatures around Greenland Island, which may weaken the Atlantic westerly jet stream and lead to amplified wave trains at the exit of the jet, resulting in strengthened anticyclones over EE and NC that favor the occurrences of HWs. The Geophysical Fluid Dynamics Laboratory high-resolution atmospheric model fails to simulate the EE and NC HWs, due probably to the model’s poor representation of the South Asian summer rainfall.