| Drought is a kind of meteorological disaster that has hurt severely agricultural production and affected economic development and people's living in China over a long period of time.Based on the research about drought and drought indices at home and abroad,this paper mainly compared and analyzed a few meteorological drought indices usually used in current domestic and international researches,and pointed out the merit and shortcoming as well as applicability of each drought index.The percentage of precipitation anomaly(Pa) has several characteristics,such as simple calculation,easy to obtain data,slow extent of response to the drought,and no reflection of the inherent mechanism of the drought.With sensitive response to drought,the standard precipitation index(SPI) can be applied to different time scales and stability calculation,while the Palmer drought index(PDSI) not only reflects the extent of drought but also includes the start and end time of drought. |