安徽大别山区5—8月不同阶段降水时空分布特征

Distribution Characteristics of Precipitation in Different Stages from May to August in Dabie Mountain Area of Anhui Province

利用2008—2016年中国区域CMORPH(Climate Prediction Center Morphing)多卫星降水数据相融合的、分辨率为0.1°×0.1°的逐时降水量数据集,将每年5—8月分为梅雨前(5月1日至入梅前1日)、梅雨期(入梅当日至出梅当日)和梅雨后(出梅次日至8月31日),分析了大别山区梅雨季节降水的时间和空间演变趋势。大别山区梅雨期间年平均降水量360.3 mm,梅雨前平均降水量279.7 mm,梅雨后平均降水量287.0 mm。梅雨季节主要存在3个降水大值区:山区北侧中段、主峰东南侧和西南侧。从日变化情况来看,梅雨期降水日变化呈现双峰特征,出现峰值的时间分别是09:00、16:00。梅雨前、梅雨后降水日变化呈单峰特征。强降水出现频率的空间分布大值区也随着梅雨前—梅雨期—梅雨后的时间变化逐渐北抬。

Using the hourly precipitation data of the automatic ground station from 2008 to 2016 with a resolution of 0.1°×0.1°, integrated with the multi-satellite precipitation data from the Climate Prediction Center Morphing(CMORPH), the Meiyu season will be divided into three periods: before Meiyu(from May 1 st to the day before the Meiyu starting), during Meiyu(from Meiyu starting to Meiyu ending) and after Meiyu(from the day after Meiyu ending to August 31 st). This paper analyses the temporal and spatial characteristics of precipitation during the rainy season in the Dabie Mountains area and concludes that: During the rainy season, the average annual precipitation was 360.3 mm, and the average precipitation before and after the rainy season was 279.9 mm, 287.0 mm, respectively. There were three major precipitation areas in the Meiyu season, distributed in the middle section of the north side of the Dabie Mountains, the southeast side and the southwest side of the central peak. The diurnal precipitation variation during the Meiyu period presented a bimodal characteristic, with the peak time at 9 o’clock and 16 o’clock, respectively. The diurnal variation of precipitation before and after the rainy season showed a single peak. The large occurrence probability of heavy precipitation in spatial distribution also gradually rose with the three periods of before Meiyu, during Meiyu and after Meiyu.