Solar 11-Year Cycle-Modulated North–South Contrasting Patterns of Summer Precipitation in China

Abstract Solar forcing exerts a notable influence on driving variability in monsoon patterns. However, the connection between decadal shifts in monsoon precipitation patterns and solar cycles remains ambiguous. This study delves into assessing the impact of the 11-yr solar cycle on precipitation patterns during the East Asian summer monsoon (EASM) spanning from 1958 to 2020. Results indicate that the summer precipitation pattern on a decadal time scale, characterized by reverse variations in northern and southern China, can be attributed to the solar precipitation regime. The solar precipitation regime, intricately tied to the East Asia/Pacific (EAP) teleconnection, is impacted by zonal winds and convection in the western Pacific. In early summer, the EAP teleconnection is partially influenced by the solar signal in the stratosphere. During high solar years, the stratospheric ozone’s heating response to solar radiation induces a warm anomaly in the tropical and subtropical lower stratosphere. This anomaly initiates anomalous convection in the troposphere, reinforcing the tropospheric EAP teleconnection and causing a northward shift in the rain belt. Additionally, the warm anomaly intensifies midlatitude westerly winds in the lower stratosphere and upper troposphere, facilitating the downward propagation of signals and bolstering the EAP teleconnection. Consequently, the EAP teleconnection amplifies solar signals in the EASM region, fostering droughts in southern China and flooding in northern China during high solar years. These findings propose a mechanism through which the sun shapes the spatial pattern of precipitation and enhance our understanding of decadal variability of monsoon precipitation. Significance Statement Solar forcing significantly influences the variability of monsoon patterns. However, the connection between decadal variation of monsoon precipitation patterns and solar cycles remains ambiguous. This study investigates the summer precipitation pattern, characterized by reverse variations in northern and southern China, which is found to be associated with the 11-yr solar precipitation regime. We propose a mechanism by which the sun influences the precipitation regime through the East Asia/Pacific teleconnection, thereby enhancing our understanding of the decadal variability of monsoon precipitation.