基于标准化降水指数的贵州省近54a干旱时空特征分析

近年来我国干旱灾害频繁发生,对人们生活、生产造成了严重影响。本文以贵州省为例,选用标准化降水指数为干旱指标,分析年度和季节的干旱发生频率的变化特征。结果表明：近54年来,贵州省年季和季节干旱总体上呈现阶段化趋势,整体表现为干旱增加趋势,1980s中后期和21世纪初期是干旱频发期。干旱频率在空间分布上差异显著,东部地区年尺度干旱较为常见;季节尺度上,除了夏旱高频区呈零星状分布外,其他如春旱主要发生于中部及东部地区,秋旱高发区集中分布于中部和东北部地区,冬旱常发生于贵州省北部地区。研究表明SPI指数能够较好地反映研究区年际及季节性干旱变化特征,能为该地区制定防旱抗旱措施提供理论支撑。

Spatial and Temporal Characteristics of Drought in Guizhou Province in Recent 54 Years Based on Standardized Precipitation

In recent years, China"s arid disasters have occurred frequently. Drought disasters have had a serious impact on people"s lives and production. Taking the Guizhou Province as an example, the standardized precipitation index SPI is selected as the drought index. This method is used to analyze the variation characteristics of annual and seasonal drought frequency. The results show that over the past 50 years, the annual season and seasonal drought in Guizhou Province have a general trend, and the overall trend is drought increasing. The late 1980s and the early 21st century were drought. Seasonal scale, in addition to the summer drought high frequency area was sporadic distribution, the other such as spring drought mainly occurred in the central and eastern regions. The high drought zone is concentrated in the central and northeastern regions, and winter drought often occurs in the northern part of Guizhou Province. The results show that the SPI index can reflect the characteristics of interannual and seasonal drought in the study area, and provide theoretical support for the drought prevention and drought control measures in the area.