Increasing autumn drought over southern China associated with ENSO regime shift

In the two most recent decades, more frequent drought struck southern China during autumn, causing an unprecedented water crisis. We found that the increasing autumn drought is largely attributed to an ENSO regime shift. Compared to traditional eastern Pacific (EP) El Nino, central Pacific (CP) El Nino events have occurred more frequently, with maximum sea surface temperature anomalies located near the dateline. Southern China usually experiences precipitation surplus during the autumn of EP El Nino years, while the CP El Nino tends to produce precipitation deficits. Since the CP El Nino has occurred more frequently while EP El Nino has become less common after the early 1990s, there has been a significant increase in the frequency of autumn drought. This has implications for increasing precipitation shortages over southern China in a warming world, in which CP El Nino events have been suggested to become more common.