Decadal Variations in the Summer Precipitation Over Eastern China Associated With Spring Arctic Sea Ice

This study investigated the contribution of Arctic sea ice concentration (SIC) on decadal variations of the dominant mode of summer precipitation over eastern China during 1981-2020. The spatial pattern of leading empirical orthogonal function mode has changed from a dipole pattern with negative anomalies over Jianghuai Valley and positive anomalies over southern China during 1981-2001 to the Yangtze River Valley (YRV) pattern during 2002-2020. Spring SIC over Kara Sea was significantly related to the dipole pattern, through influencing Eurasian snow depth. The associated anomalous temperature gradient and atmospheric circulation affected the meridional displacement of the East Asian subtropical jet, which favored the dipole pattern of summer precipitation. For the YRV pattern, spring SIC over Greenland Sea has an impact on the sea surface temperature anomalies in the western Pacific by triggering a wave train that influenced the precipitation through the establishment of the Pacific-Japan pattern. The results of this study may provide reference value for the prediction of summer precipitation over eastern China.