摘要
基于降水量、平均气温、日照时数等气候数据及土壤湿度资料,用相关分析和典型相关法,针对云南多种气候类型下包含秋-冬-春连旱的一个大旱年,比较分析气候干湿指数(I)、相对湿润度(M)、综合气象干旱指数(Ci)、降水距平百分率(Pa)和标准化降水指数(SPI)5个干旱指标在农业干旱监测评估中的适用性。结果表明,5个干旱指标对0-20cm土层相对湿度(SM)时空变化的解释能力排序为:I>M>Ci>Pa>SPI,其中前3种指数的解释度分别为89.66%、85.47%和82.59%;Pa和SPI主要反映降水波动变化,难以准确表达旱涝气候和农业干湿变化;Ci对降水变化的响应过于敏感,不太适用于部分天气气候下的农业干旱监测/评估。I、M辨识干湿变化能力强,适用范围广,对农业旱涝监测评估的适用性优于其它3个指标,但在较长持续重旱期敏感性欠佳,可结合使用低于某临界值的持续时间长度来表达干旱强度和持久性。
The applicability for monitoring and evaluation agricultural drought of five drought indices ,including climate dry - wet index （ I ）, relative moisture index （ M ）, comprehensive meteorological drought index （ C ）, precipitation anomaly percentage （Pa） and standardized precipitation index （ SPI）, was analyzed in Yunnan province by using of the correlation analysis and canonical correlation methods, based on the data of precipitation, average temperature, sunshine duration and soil moisture from August 2009 to July 2010 along with other climatic data in Yunnan. The results showed that the explanation capability of these indices to the temporal - spatial variation of soil moisture （SM） was as follows ： I 〉 M 〉 Ci 〉 Pa 〉 SPI, among which the explanation capability of the first three indices was 89. 66%, 85.47% and 82. 59% respectively. Pa and SPI were not able to express the changes of agricultural natural dry-wet status accurately because of their primary expression for rainfall fluctuation. Ci was still so sensitive to precipitation fluctuation that it was not suitable for being used in varied climates to a certain extent. I and M distinguished natural dry-wet changes well so were available to more immense areas. They were superior to other three indexes while used in estimating agricultural drought and flood under various climates. But both I and M had less susceptibility while used in the persistent severe - drought indicate periods of long duration, when the length of duration time for index values below some critical values could the intensity and persistence of drought.
出处
《中国农业气象》
CSCD
北大核心
2013年第2期221-228,共8页
Chinese Journal of Agrometeorology
基金
气象行业专项"多时间尺度干旱监测与预警
评估技术研究"(GYHY201006023)
关键词
土壤相对湿度
气候干湿指数
相对湿润度
Ci指数
农业干旱
适用性
Soil relative moisture
Climate dry-wet index
Relative moisture index
Comprehensive meteorologicaldrought index
Agricultural drought
Applicability
