不同干旱指标在新疆喀什地区的运用对比研究

Comparison of different drought index in Kashgar area in Xinjiang,China

本文基于新疆喀什地区1952-2008年近57气象资料,分别运用标准化降水指数SPI、降水百分位指数PDECI以及干旱侦测指数RDIst三种干旱指标定量评价了新疆喀什地区的干旱情况,并结合研究区2000-2008年实际干旱情况进行验证分析,从而评价出较适合于研究区的干旱指标计算方法,研究结果表明:在新疆喀什地区,在三种干旱指标中,SPI和RDIst的相关性较好,在月尺度上,其相关系数高达0.9725,由于RDIst考虑蒸散发对区域干旱的影响,与喀什地区实际发生的干旱情况比较吻合,且RDIst指标具有较稳定的计算结果,整体计算结果略优于在国内运用较好的标准化降水指数SPI,而PDECI对于降水量的变化最为敏感,其月尺度和季尺度的干旱指标均不适合于喀什地区的干旱判定,研究成果可以为新疆地区的干旱评价和水资源保护提供参考价值。

Based on the the climate data during 1952 to 2008 in the kashar area in Xijiang province,the stan- dardized precipitation index （SPI）,the precipitation percentile index （PDECI） and the drought detection index （RDIst） were used to evaluate the drought in the Xinjiang area,and the actual drought in Kashar area during 2000 year to 2008 year were used to evaluate the three drought index.The outputs shows that the SPI have a good relation with RDIst,itsrelation coefficient can be 0.9725 evaporation into account, it is the most consistent with actual at the month scale.Since the RDIst can take the drought situation in Kashar area,and the index have a more stable result,it overall result is better than SPI which is used better in the country, the PDECI is the most sensitive to precipitation,and it is not suit for drought evaluation in Kashar area in month and season scale.The outputs can take reference to drought evaluation and water resources protection in Xinjiang area.