摘要
基于河北省1961年-2010年64个气象站逐日气温和降水资料,采用综合气象干旱指数(CI)计算近50年逐日CI值,分析了河北省气象干旱发生的时空分布特征。结果表明:河北省近50年降水量以16.5mm/10年的速度递减,近10年中有7年降水量不足历年均值;各级干旱年均出现日数均为南多北少,其中冀南平原地区最多,张家口北部最少;四季中春旱最重,夏旱最轻,除夏旱为东北低、西南高外,其他时段均为北低南高的特点;近20年中有16年出现重、特旱覆盖率为100%,夏季出现大范围重、特旱的年份最多、冬季最少;秋季大范围干旱增长趋势较其他季节明显。
Located in the north of Huabei Plain,Hebei Province belongs to the warm temperate zone with a continental monsoon climate.It has a mean annual temperature of 1-14 degrees celsius and a mean annual precipitation of 340-750 mm.The drought area of Hebei Province has been expanding during the last 40 years,so it is necessary to choose a more effective method to analyze the temporal and spatial distribution of droughts.In this paper,based on the data of daily mean surface air temperature and daily precipitation from 64 meteorological stations in Hebei Province during 1961-2010,we calculated the daily drought index from 1961 to 2010 using the meteorological drought composite index（CI）,and then analyzed the spatial distribution characteristics of meteorological droughts.According to Classification of Meteorological droughts（GB/T 20481—2006）,the meteorological drought composite index（CI）has been calculated by using the standard precipitation index of the last 30 days（equivalent to monthly scale）and the last 90 days（equivalent to seasonal scale）,and the relative moisture index of the last 30 days.The results show that the annual precipitation has decreased at a rate of 16.5mm/10a in the recent 50 years,and in the past 10 years,there are 7 years in which the precipitation is lower than the average value;the drought days of different grades decrease from south to north,with the plain of southern Hebei Province having the most and the north of Zhangjiakou having the least;drought frequency in spring is the highest while that in summer is the lowest,With the occurrence frequencies decrease from southwest to northeast in summer,and decrease from south to north in the annual and the rest of the years;16 years out of the last 20 years have experienced 100 percentage of serious drought and extreme droughts;The years in which large coverage area of drought appear in summer are the most while those in winter are the least;the trend of drought increase is more obvious in autumn than in other seasons.
出处
《资源科学》
CSSCI
CSCD
北大核心
2012年第6期1089-1094,共6页
Resources Science
基金
河北省软科学研究项目:"镇抗旱全能人才信息战略"(编号:11457202D-56)
关键词
河北省
综合气象干旱指数(CI)
时空分布特征
Hebei province； The meteorological drought composite index（CI）； Temporal and spatial distribution characteristics
