黔西南州乡镇雨量站的暴雨基本特征分析

本文利用2013～2017年共五年乡镇自动站雨量,分析了暴雨、大暴雨、特大暴雨的逐月变化及空间分布特征,并就分布的空间差异性进行了探讨。结果显示：(1)黔西南州近五年特大暴雨点数累积集中出现在5-9月,其中6月最多,其次为8月；大暴雨主要出现在5-10月,6月最多；暴雨集中出现在5-9月,其中6月最多,其次为7月、9月；(2)暴雨及以上量级的雨日呈现明显的单峰结构,6月最多,达到88日,7、8月相当,11月至来年的3月暴雨日很少,大暴雨分布在4-12月,集中分布在6-9月,其中6月最多,达到27个大暴雨日,平均每年4.5日；特大暴雨分布在5-9月,其中8月最多,有4个特大暴雨日,平均每年0.8日；(3)暴雨以上量级日数夏季出现最多,其次为秋季、春季,冬季最少。暴雨、大暴雨季节变化特征相同,均为夏季最多,秋季次之,再次为春季,冬季最少；特大暴雨夏季最多,春秋季相同,均为2日；(4)近五年黔西南州暴雨及以上量级日数空间分布不均匀,总体呈现南北多中间少的特征：兴义市大部、中西部,册亨县大部,望谟县西南部,晴隆县大部,普安县北部暴雨及以上量级日数近五年合计超过20d,兴义市敬南镇、册亨县秧坝镇最多达37d,望谟县昂武乡、兴仁市新龙场镇、贞丰县沙坪镇最少,五年合计仅有6d。大暴雨日数空间总体呈现南北多中间少的特征：兴义市东南部、册亨县大部、望谟县中西部、晴隆县东部近五年合计超过5d,其中兴义市敬南镇、册亨县城、晴隆县光照镇、大田乡最多,达到8d,贞丰县、望谟县交界处近五年未出现大暴雨；特大暴雨主要出现在兴义市的东南部、兴义、兴仁交界以及兴仁的中部以北。

Basic Characteristics of Rainstorm in Southwest Guizhou Based on Township Automatic Station

This paper analyzes the data of automatic rainfall monitoring stations in QXN from 2013 to 2017, by doing so, we obtained the temporal and spatial distribution of rainstorm,downpour and extraordinary rainstorm.(1)In the past five years, extraordinary rainstorm mainly occurred in the period of May to September, with the highest in June, followed by August; downpour occurred mainly from May to October, and most in June; rainstorm concentrated in May to September, most in June, followed by July and September;(2)Temporally , the rainstorm and above precipitation showed an obvious single-peak distribution, with the largest in June, reaching 88 days. downpour, with an average of 4.5 days per year, are distributed from April to December, concentrated in June-September, with the most in June, reaching 27 heavy rain days .extraordinary rainstorm, with an average of 0.8 days per year, are distributed from May to September, with the most in August with 4 days.(3)Rainstorm and downpour are the most frequent in summer, followed by autumn, spring and winter. Extraordinary rainstorm occur most frequently in summer and the same in spring and autumn, both are 2 days.(4)In the past five years, the spatial distribution of rainstorm and downpour has been uneven, the north and south are relatively more than central part.extraordinary rainstorm mainly occurred in the southeast of Xingyi City, the junction of Xingyi and Xingren, and the north of Xingren.