Drought in Southwest China: A Review

The clustering of severe and sustained droughts in Southwest China (SWC) during the last decade has resulted in tremendous losses, including crop failure, a lack of drinking water, ecosystem destruction, health problems, and even deaths. Various attempts have been made to explore the variability and causes of drought in SWC. Here, the authors summarize and integrate this accumulated but fragmented knowledge. On the whole, general agreement has been reached on the evolution of drought in SWC, which has become more frequent and intense during the past 50 years and is projected to continue throughout the 21st century. However, it is unclear and even disputable as to what and how sea surface temperatures and circulation oscillation patterns affect the drought condition. Meanwhile, the presence of strong nonlinearity places considerable challenges in both understanding and predicting drought in SWC. Therefore, much remains to be learned concerning the mechanisms responsible for drought disasters in SWC and accurate forecast practice. In addition to pursuing research on factors and processes involved in drought formation, above all, there is an urgent need to develop appropriate strategies and plans for mitigating the threats of drought.