VARIATION AND CAUSES OF PERSISTENT DROUGHT EVENTS IN GUANGDONG PROVINCE

Variation characteristics of persistent drought events in Guangdong province are analyzed using 45-year (1961-2005) and 86-station observational precipitation data of Guangdong, and the causes of drought events are discussed from different angles (e.g., atmospheric circulation, sea surface temperature) on the basis of global coverage datasets of sea surface temperature and atmospheric elements. It is found that the occurrence frequency of persistent drought events in Guangdong province is once every 26 months on average, and autumn-winter or winter-spring persistent drought events take up the majority. The persistent drought events possess large scale spatial characteristics. While the 1960s is the most frequent and strongest decade of drought events in the latter half of the 20th century, the occurrence is more frequent and the intensity is stronger in the first five years of the 21st century (2001-2005). This reflects the response of regional extreme climatic events in Guangdong to global climatic change. The atmospheric circulation, sea surface temperature, etc, appear to have different abnormal characteristics when drought events happen in different seasons. The results of this paper provide some good reference information for the drought forecast, especially for the dynamic interpretation of climatic model products.