基于降水量距平百分率的内蒙古地区干旱特征  

Drought Characteristics in Inner Mongolia Based on Precipitation Anomaly Percentage

作　　者：吴英杰[1] 李玮[1] 王文君 全强 陈晓俊 尹航 周泉成 徐凯然 WU Ying-jie;LI Wei;WANG Wen-jun;QUAN Qiang;CHEN Xiao-jun;YIN Hang;ZHOU Quan-cheng;XU Kai-ran(Institute of Water Resources for Pastoral Area,China Institute of Water Resources and Hydropower Research,Hohhot 010020 Jnner Mongolia,China)

机构地区：[1]中国水利水电科学研究院牧区水利科学研究所

出　　处：《干旱区研究》2019年第4期943-952,共10页Arid Zone Research

基　　金：内蒙古自治区自然科学基金项目(2015MS0387,2017BS0512);中国水利水电科学研究院科研专项项目(MK2016J08,MK2016J02);国家自然科学基金项目(51579157,51779156)

摘　　要：利用1971-2015年内蒙古地区52个气象站逐月降水量观测数据,采用降水量距平百分率(Pa),从干旱频率和干旱变化趋势率分析了研究区近45 a来干旱时空分布特征。结果表明:从时间变化来看,年降水量呈微弱的下降趋势,并于1998年和2012年发生突变;春季、秋季和冬季降水量变化呈上升趋势,夏季降水量变化呈下降趋势;年尺度干旱主要发生在1999-2011年;季节尺度干旱发生频率为冬旱>春旱>秋旱>夏旱。从空间变化来看,多年平均降水量由东向西呈逐级递减趋势,降水分布地域特征明显,大兴安岭以东地区和巴彦淖尔市西部地区降水变化趋势率较高,呼伦贝尔市西北部、通辽市中南部、赤峰市中部、阿拉善盟西部地区降水变化趋势率较低;发生不同等级干旱的几率为轻旱>特旱>中旱>重旱,各级干旱易发生地区集中在呼伦贝尔市西部、赤峰市中北部、通辽市北部、锡林郭勒盟中西部以及阿拉善盟西部地区。Pa变化趋势率表现为,呼伦贝尔市中东部、巴彦淖尔市西部和阿拉善盟东部呈上升趋势,即干旱程度减轻;兴安盟南部至鄂尔多斯市、阿拉善盟中西部呈下降趋势,即干旱程度加重。The monthly precipitation data from 52 meteorological stations in Inner Mongolia from 1971 to 2015 were used. The methods of M-K test and precipitation anomaly percentage (Pa) were used to analyze the change trend and abrupt change of precipitation,and the spatiotemporal variation of drought at different time scales was also analyzed. The results showed that the inter-annual precipitation variation trend was basically maintained,and two abrupt changes took place in 1998 and 2012 in recent 45 years. Precipitation increased in spring,autumn and winter,but it was opposite in summer. Drought events occurred mainly in winter during the period from 1999 to 2011,and their frequency was the lowest in summer. Spatially,the annual precipitation decreased gradually from the east to the west. The change rate of precipitation was high in the area east of the Greater Khingan Mountains and west Bayan Nur,but it was low in Northwest Hulun Buir,central and southern parts of Tongliao,central part of Chifeng,and western Alxa. In addition,the probability of occurring drought at different levels was in an order of slight drought > extreme drought > moderate drought > severe drought. Drought events occurred generally in west Hulun Buir,Central-North Chifeng,North Tongliao,Central-West Xilin Gol League and West Alxa League. The Pawas in an increase trend in Central-East Hulun Buir,West Bayan Nur and East Alxa League,but it was in a decrease trend from South Hinggan League to Erdos and in Central-West Alxa.

关 键 词：干旱等级 降水量距平百分率(Pa) 内蒙古 

分 类 号：P426.616[天文地球—大气科学及气象学]