Dominant modes of interannual variability of extreme high‐temperature events in eastern China during summer and associated mechanisms

• Published in: International Journal of Climatology
• Main Authors: Zhu, Baoyan, Sun, Bo, Wang, Huijun
• Other Authors: National Key Research and Development Program, National Natural Science Foundation of China, Natural Science Foundation of Jiangsu Province
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2019
• Subjects: Pacific; North Atlantic
• Online Access: http://dx.doi.org/10.1002/joc.6242; https://onlinelibrary.wiley.com/doi/pdf/10.1002/joc.6242; https://onlinelibrary.wiley.com/doi/full-xml/10.1002/joc.6242; https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/joc.6242

Abstract This study investigated the interannual variability of the frequency of extreme high‐temperature events (FEHE) during summer over eastern China and associated mechanisms. Two leading modes of interannual variability of FEHE over eastern China during summer are obtained by Empirical Orthogonal Function (EOF) analysis. The first EOF (EOF1) mode of FEHE shows a diploe pattern characterized by positive (negative) anomalies in northeastern (southern) China. The second EOF (EOF2) mode of FEHE shows a monopole pattern characterized by positive anomalies in the Yangtze River valley (YRV) region. The potential mechanisms of the two leading modes are different. The EOF1 of FEHE is modulated by the EOF1 of 500‐hPa geopotential height (Z500) over Eurasia, which exhibits a Eurasian wave train associated with the air–sea interaction over the North Atlantic. Besides, anomalous SSTs over the western tropical Pacific and associated anomalous convective activity over the Maritime continent may also exert an impact on the EOF1 of FEHE via stimulating a meridional wave train, the so‐called “Pacific‐Japan/East Asia‐Pacific” teleconnection. The EOF2 of FEHE is mainly associated with the NAO mode.