Applicability Analysis of Different Meteorological Drought Index in Oasis Agricultural Area of Northern Xinjiang
Selecting data from the oasis agricultural area 11 stations of Northern Xinjiang from 1961 to 2020, five drought indices were calcu-lated on a monthly scale, including the precipitation anomaly percentage (PA), standardized precipitation index (SPI), standardized precipi-tation evapotranspiration index (SPEI), K index and meteorological drought composite index (MCI).By comparing the correlation, frequency of drought occurrences at different levels and the ability to identify typical drought years among these indices, we analyzed their applicability in the region.The result showed that PA and SPI were sensitive to precipitation deficits but had a weaker correlation with temperature, failing to fully consider the impact of warming on droughts; MCI also had weaker correlations with temperature and precipitation, tending to underesti-mate severe and exceptional drought situations; both SPEI and K index showed a better correlation with temperature and precipitation, but the K index reported moderate to severe droughts excessively, while SPEI more comprehensively considered the combined effect of temperature and precipitation on droughts, making its results more realistic.However, due to the Thornthwaite method used by SPEI, which may overestimate the impact of temperature on drought, in cases of significantly less precipitation and minor temperature deviations, SPI's monitoring results may be more severe than SPEI's.Therefore, it was recommended to use SPI in conjunction with SPEI to compensate for this shortcoming.
Meteorological drought indicesMonthly scaleApplicabilityOasis agricultural area of Northern Xinjiang
国家科技期刊平台
NSTL
万方数据
