Drought and flood characteristics evolution in peninsular region of Shandong Province based on standardized precipitation index

Abstract

Data research in recent decades shows that drought and flood disasters occur frequently in China due to the uneven spatial and temporal distribution of rainfall. Taking Shandong Peninsula as an example, this work selected the standard precipitation index (SPI) as the precipitation characteristic analysis index, calculated the SPI values at 4 different time scales in multiple meteorological stations from 1961 to 2013, and analysed the inter annual and seasonal variation characteristics of drought and flood. The results show that: (1) the standardized precipitation index can better reflect the characteristics of inter annual and seasonal drought and flood changes in the study area on a long time series scale. (2) The most flood period occurred in 1964 and 2007, and the most drought period occurred in 1981, 1991 and 1998, and all reached the severity of extreme drought. (3) The intensity of drought and flood varied in different time scales. In spring, autumn and winter, the drought intensity and affected area showed a decreasing trend. However, the flood intensity and its affected area were on the rise in summer, and the rainfall intensity was on the rise in time scale.