1917年以来重庆市气象干旱时空演变分析  

Spatio-temporal Evolution Analysis of Meteorological Drought in Chongqing City Since 1917

作　　者：林孝松 张莉 余情 廖青松 LIN Xiaosong;ZHANG Li;YU Qing;LIAO Qingsong(College of Architecture and Urban Planning,Chongqing Jiaotong University,Chongqing 400074,China;College of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学建筑与城市规划学院,重庆400074 [2]重庆交通大学土木工程学院,重庆400074

出　　处：《灾害学》2024年第3期9-15,共7页Journal of Catastrophology

基　　金：国家自然科学基金“山区县域公路洪灾形成机制研究”(41601564);重庆市气象局气象部门业务技术攻关项目“大巴山复杂地形下强降雨引发的山洪灾害预警研究”(YWJSGG202218)。

摘　　要：干旱问题复杂性较强,对气象干旱特征进行分析可进一步揭示其演变规律,为减少灾情损失提供科学依据。该文基于重庆市1917—2017年逐月降水格网数据,计算标准化降水指数值,采用干旱频率、干旱站次比、干旱强度和时空扫描等方法,对研究区近100 a气象干旱时空特征进行分析。结果表明:①春旱和冬旱频率较高,夏旱和秋旱频率略低,各等级干旱频率分布存在较明显差异,总体呈东北部高,并依序向西南、东南两个方向递减且在渝西部分区县略有回升特征;②年干旱和季节干旱均以全域性为主,春季和冬季占比超过70%,影响范围广,应做好系统性防旱减灾工作;③各站点年均干旱强度在0.54~1.66之间,年和季节干旱以轻旱和中旱为主,但需关注季节性重旱和特旱;④具有较明显年际和不同等级干旱时空聚集特征,干旱集聚时长、案例数和影响范围随时间推移不断增加然后迅速回落。The complexity of drought issues has increased.Analyzing the meteorological drought characteris⁃tics in Chongqing can further reveal their evolution patterns and provide scientific basis for reducing disaster losses.Based on the monthly precipitation grid data of Chongqing from 1917 to 2017,the standardized precipitation index value is calculated.Methods such as drought frequency,drought station ratio,drought intensity,and spatiotem⁃poral scanning are used to analyze the spatiotemporal characteristics of meteorological drought in the study area for nearly 100 years.The results show that:①The frequency of spring drought and winter drought is higher,while the frequency of summer drought and autumn drought is slightly lower.There are significant differences in the dis⁃tribution of drought frequencies at different levels,with the overall trend being higher in the northeast and decreas⁃ing in the southwest and southeast directions in sequence,with a slight rebound in the counties in the western part of Chongqing.②Both annual and seasonal droughts are mainly regional in nature,with spring and winter account⁃ing for over 70%and having a wide range of impacts.Therefore,systematic drought prevention and disaster reduc⁃tion work should be done well.③The average annual drought intensity at each station ranges from 0.54 to 1.66,with light and moderate drought being the main types of annual and seasonal drought,but attention should be paid to seasonal heavy and extreme drought.④It has obvious interannual and different levels of drought spatiotemporal clustering characteristics,and the duration,number of cases,and impact range of drought clustering continue to increase over time and then rapidly decline.

关 键 词：气象干旱 时空演变 标准化降水指数 时空扫描 重庆市 

分 类 号：P429[天文地球—大气科学及气象学] X43[环境科学与工程—灾害防治] X915.5