Characteristics of Drought at Multiple Time Scales in the East of Northwest China from 1901 to 2012
The Standardized Precipitation Evaportranspiration Index (SPEI) considering precipitation and temperature is calculated using CRU update data at multiple time scales,and is compared to Standardized Precipitation Index (SPI).The characteristics of drought at different time scales from 1901 to 2012 in the east of northwest China have been investigated.In this paper,reliability for hundred years of the CRU data has been tested,and the adaptability of SPEI in studied area has been discussed.The result shows that the CRU data is reliability,but due to the properties of CRU material,there is uncertainty for the data before 1920.The SPEI is confirmed to be applicable to analyze the drought in the east of northwest China from drought intensity and range.Changes of a fluctuating of SPEI and SPI at different time scales are consistent.Short time scale mainly shows seasonal characteristics,and long time scale shows interannual and decadal characteristics.The study area is divided into the eastern of the plateau area and the southern of Shaanxi area.There are 4 dry periods in the eastern of the Plateau area and 5 dry periods in the southern of Shaanxi area from 1901 to 2012.Finally,the contribution of temperature anomaly to the drought is analyzed.The result indicates that high temperature contribution cannot be neglected by comparison with the SPI index.
standardized precipitation evapotranspiration indexmultiple time scalesdroughtthe east of northwest China
NETL
NSTL
万方数据
