Analysis of spatio-temporal characteristics of precipitation in Liaoning province from May to October during 2016-2021
Utilizing hourly high-density precipitation observation data from May to October during 2016-2021 in Liaoning province,this study analyzed the spatio-temporal distribution characteristics of precipitation processes,short-term heavy precipitation events,and extreme short-term heavy precipitation events.The K-means clustering method was applied to classify the spatial distribution of cumulative precipitation hours during short-term heavy precipitation events in the flood season.The results indicated that short-term heavy precipitation events(hourly precipitation≥20 mm)and extreme short-term heavy precipitation events(hourly precipitation≥99.9th percen-tile of historical precipitation at the station)are significantly influenced by topography.High-frequency areas of short-term heavy precipitation are primarily in the southeastern coastal regions of Liaoning province,the coastal plains and areas with higher elevation in western Liaoning province,and the windward slopes in southeastern Lia-oning province.Precipitation during the flood season in Liaoning province is affected by monsoon circulation,ex-hibiting distinct seasonal variations.The maximum average precipitation and precipitation frequency occur in July and August,and mainly concentrate from afternoon to night.Considerable regional differences are found in the fre-quency of short-term heavy precipitation events across Liaoning province,while the regional differences in extreme short-term heavy precipitation events are relatively minor.
The number of cumulative hoursK-means clusteringShort-term heavy precipitationHigh-density au-tomatic weather stations