干旱区研究2025，Vol.42Issue(6)：970-980,11.DOI:10.13866/j.azr.2025.06.02
甘肃河东夏季区域性短时强降水特征
Characteristics of regional heavy rain showers in eastern Gansu Province
摘要
Abstract
Using hourly precipitation data collected from automatic weather stations(AWS)in eastern Gansu Province during the summer months from 2010 to 2021,a total of 50 regional heavy rain showers were identified.An analysis was then conducted to examine the spatiotemporal distribution and intensity of such events in eastern Gansu Province.The obtained results can be summarized as follows:(1)The intensity of the heavy rain showers primarily ranged between 20 and 30 mm·h-1,which accounted for more than 60%of such events.Intensities ex-ceeding 40 mm·h-1 represented less than 10%of such events.Notably,short bouts of intense precipitation with in-tensities exceeding 50 mm·h-1 occurred in 74%of the heavy rain showers in the studied region.(2)In the studied region,heavy rain showers mainly occur from mid-June to late August,peaking in the period from late July to mid-August.While such events occur throughout the year,the interannual variability in their occurrence is signifi-cant and closely associated with the position of the Western Pacific subtropical high,the transport of abnormally warm water vapor from the South China Sea or East China Sea,and significant baroclinic features resulting from the interaction of weather systems at mid-and low latitudes.(3)The area typically affected by heavy rain showers in eastern Gansu Province accounts for only 3.17%of its total area.However,there are notable regional varia-tions in the spatial distribution of these events,with areas struck by high-intensity rainfall being primarily located in the Taizishan region,the western section of the Qinling Mountain,Liupan Mountain,and Ziwu Mountain.Ad-ditionally,areas affected by rainfall of extreme intensity,exceeding 40 mm·h-1,are concentrated in these high-in-cidence centers.(4)There is a clear pattern in the distribution of stations recording heavy rain showers under dif-ferent circulation patterns.Stations associated with the eastward-moving plateau trough type are dispersed and most abundant.Meanwhile,stations related to the subtropical high's southwestern airflow type record the lowest median number of such events.Finally,stations experiencing shear between two high-pressure systems are con-centrated,while those associated with the northwest airflow type are the least numerous.There was no significant difference in the distribution of the events with heavy rainfall intensity among these circulation types.However,rainfall intensities between 30 and 50 mm·h-1 are more likely to occur in the two high-shear types.关键词
甘肃河东/短时强降水/天气过程/时空分布Key words
eastern Gansu Province/short-time heavy rainfall/weather events/spatiotemporal distribution引用本文复制引用
孔祥伟,李晨蕊,邸文婧,杨毅,付正旭,杨秀梅..甘肃河东夏季区域性短时强降水特征[J].干旱区研究,2025,42(6):970-980,11.基金项目
甘肃省气象局创新团队(GSOXCXID-2024-01) （GSOXCXID-2024-01）
甘肃省青年科技基金计划(23JRRA1328) （23JRRA1328）
干旱气象科学研究基金项目(IAM202207) （IAM202207）
中国气象局创新发展专项(CXFZ2023J068) （CXFZ2023J068）
