资源环境科技发展态势分析平台

The 11-year solar cycle (SC) has been widely recognized as a potential source of regional climate variability in the Northern Hemisphere winter. However, whether an SC signal exists in the southern China winter precipitation remains unclear. By analyzing land surface precipitation and sunspot number data from 1901 to 2010 in this study, evidence of a robust positive precipitation response that is synchronous with the SC in late winter (January-March) over southern China is provided, and the most statistically significant signals (p < 0.01) are detected over the middle Yangtze River basin. In early winter (October-December), there are only nonsignificant negative responses. The late winter SC-precipitation relationship persists over time and appears to largely result from a solar-associated Rossby wave train originating from the North Atlantic/European region. Our results indicate an enhanced predictability of late winter precipitation over southern China.

Plain Language Summary During winter, severe rainfall/snowstorm events occasionally occur in southern China, leading to catastrophic social and economic consequences, and the causes of these events have recently become the focus of the scientific community. However, it remains unknown whether the 11-year solar cycle influences southern China winter precipitation anomalies. Our results suggest that late winter (January-March) precipitation tends to increase (decrease) significantly during strong (weak) solar activity years over southern China, especially over the middle Yangtze River basin. The solar-precipitation linkage is relatively weak in early winter (October-December). The physical mechanism behind this linkage is also explored. Considering the quasiperiodicity of the 11-year sunspot cycle, our results have the potential to improve decadal predictions of late winter precipitation over southern China.