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Description
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 influence of the 11-year solar cycle on East Asian summer monsoon precipitation from 1958 to 2020, revealing that the decadal-scale pattern of opposing rainfall anomalies between northern and southern China is driven by a solar-coupled mechanism linked to the East Asia/Pacific teleconnection. During high solar activity years, stratospheric ozone heating in response to enhanced solar radiation generates a warm anomaly in the tropical and subtropical lower stratosphere, which triggers anomalous convection in the troposphere, reinforces the EAP teleconnection, and shifts the rain belt northward. This warm anomaly also strengthens midlatitude westerlies in the upper troposphere and lower stratosphere, aiding the downward propagation of the solar signal and further amplifying the EAP pattern. As a result, the EAP teleconnection channels solar influence into the EASM region, producing drought in southern China and flooding in the north. These findings propose a stratosphere–troposphere coupling mechanism through which solar variability shapes spatial precipitation patterns, offering new insights into the decadal variability of monsoon rainfall.