基于TRMM降水数据的云南干旱分析

根据2008~2012年TRMM3B43降水数据,通过计算TRMM降水距平和累积降水距平,分析云南省不同时间尺度下干旱的时空分布特征。结果表明,云南省干旱受降水影响显著,干旱主要发生在1、2、11和12月,其中特旱主要出现在11和12月,重旱主要出现在11、2、12和1月,中旱主要发生在12和2月,轻旱主要发生在2月,而在干旱频发月份中,干旱主要出现在滇中和滇西南地区;从云南省干旱累计来看,干旱主要出现在10月~次年1月,且主要出现在滇中地区;TRMM数据可用于中长期的旱情监测与评估,相对站点实测数据更适合于大尺度空间上宏观性的干旱监测。

Analysis on Drought in Yunnan Based on TRMM Precipitation Data

Based on the TRMM3B43 precipitation data from 2008 to 2012, TRMM precipitation anomaly and accumulated precipitation anom-aly was calculated to study temporal and spatial distribution characteristics of drought in Yunnan Province in different time scale.The results showed that, precipitation was the main factor affecting drought in Yunnan Province, drought mainly occurred in Feb., Jan., Nov.and Dec., the special drought mainly occurred in Nov.and Dec., the heavy drought mainly occurred in Nov., Feb., Dec.and Jan., the moderate drought mainly occurred in Dec.and Feb., the light drought mainly occurred in Feb., in the drought prone months, the drought mainly hap-pend in central area of Yunnan and southwestern Yunnan;From the cumulative drought in Yunnan Province, the drought mainly occurred from Oct.to Jan.Of next year and mainly happend in central area of Yunnan;TRMM data can be used for medium and long-term drought monito-ring.TRMM data are more suitable than measured data in wide-range drought monitoring.