Using minute rainfall data of automatic ground station and a variety of products from new generation Doppler weather radar in Wuchuan, the characteristics of a short-time heavy precipitation process on April 23, 2022 ...Using minute rainfall data of automatic ground station and a variety of products from new generation Doppler weather radar in Wuchuan, the characteristics of a short-time heavy precipitation process on April 23, 2022 were analyzed. The results showed that the appearance of differential reflectivity(ZDR) column and big-value zone of high-elevation ZDR had better indication on short-term heavy rainfall process in Shichao station. Ice phase process played a very important role in particle growth. The storm tracking information product can predict the path of the storm 15 min in advance. The storm stayed and moved less or even turned back to more than two to three scanning volumes in one place, indicating the occurrence of short-term heavy rainfall. One-hour accumulated precipitation(OHP) had a good effect on the estimation of continuous precipitation in a large area where the hourly rainfall exceeded 50 mm for more than two stations. It had the ability to estimate short-term heavy precipitation in areas lacking automatic stations.展开更多
选用2013—2020年6—8月河北省中南部(冀中南)地区1115个自动站逐小时降水数据与地形高度资料,统计该地区夏季小时强降水(hourly heavy rainfall,HHR)和暴雨日的发生频次、持续时间、降水强度等方面的分布特征。结果表明:冀中南地区夏...选用2013—2020年6—8月河北省中南部(冀中南)地区1115个自动站逐小时降水数据与地形高度资料,统计该地区夏季小时强降水(hourly heavy rainfall,HHR)和暴雨日的发生频次、持续时间、降水强度等方面的分布特征。结果表明:冀中南地区夏季发生频次为2.2~3.0次·a-1的HHR对降水贡献率大于35%,高频区有6个,在沧州东部沿海呈片状分布,在西部山区呈点状分布。小于60 mm·h^(-1)的HHR发生站次日变化特征为单峰、单谷,60 mm·h^(-1)以上发生站次随降水强度增大而锐减,日变化特征不明显。降水性质方面,冀中南地区的西部山区HHR高频区多积状云对流性降水,常发生在12:00—18:00;沧州东部沿海多受台风和切变线影响,HHR为降水强度较大的层状云和积状云混合性降水。展开更多
Based on the data of hourly precipitation in 11 national stations and 262 regional stations in Ulanqab City from 2017 to 2022,the annual,monthly and daily variations of short-term heavy precipitation in Ulanqab City w...Based on the data of hourly precipitation in 11 national stations and 262 regional stations in Ulanqab City from 2017 to 2022,the annual,monthly and daily variations of short-term heavy precipitation in Ulanqab City were statistically analyzed.The results show that the frequency of short-term heavy precipitation in Ulanqab City was high in the south and low in the north,and was closely related to the terrain.Short-term heavy precipitation in Ulanqab City was mainly concentrated from June to August,of which it was the frequentest in July.Short-term heavy precipitation mainly occurred from the afternoon to evening,and was concentrated from 13:00 to 20:00,especially at 19:00.The rainfall in Ulanqab City ranged mainly from 20 to 30 mm,accounting for 74.7%,and the rest accounted for 25.3%.展开更多
为提高暴雨预报准确率,减少暴雨致灾损失,基于地面常规气象观测资料、卫星云图反演的云顶亮温(Black Body Temperature,TBB)资料及美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)再分析资料,对2017年8月云...为提高暴雨预报准确率,减少暴雨致灾损失,基于地面常规气象观测资料、卫星云图反演的云顶亮温(Black Body Temperature,TBB)资料及美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)再分析资料,对2017年8月云南一次强对流暴雨成因进行分析。结果表明:500 hPa低槽东移、700 hPa切变线南压、地面冷锋西推是此次降水过程发生的天气背景;中-β、中-α尺度对流系统(Mesoscale Convective System,MCS)是产生强对流暴雨的直接系统,强降雨主要出现在TBB梯度大值区;MCS与700 hPa切变线关系最为密切,切变线位于滇中以东地区,MCS呈椭圆状,沿切变线附近及后部发展,切变线靠近哀牢山或翻越后,MCS呈西北—东南向带状分布,沿切变线前部发展;切变线翻越哀牢山前,白天移动较快,主要产生雷暴天气,夜间移动缓慢,降雨较强;强对流暴雨需重点关注水汽通量辐合大值区、800 hPa与500 hPa温差大于20℃区域;强降雨时段,整层大气均为上升运动,强降雨区维持低层辐合、中高层辐散的动力抽吸机制。展开更多
文摘Using minute rainfall data of automatic ground station and a variety of products from new generation Doppler weather radar in Wuchuan, the characteristics of a short-time heavy precipitation process on April 23, 2022 were analyzed. The results showed that the appearance of differential reflectivity(ZDR) column and big-value zone of high-elevation ZDR had better indication on short-term heavy rainfall process in Shichao station. Ice phase process played a very important role in particle growth. The storm tracking information product can predict the path of the storm 15 min in advance. The storm stayed and moved less or even turned back to more than two to three scanning volumes in one place, indicating the occurrence of short-term heavy rainfall. One-hour accumulated precipitation(OHP) had a good effect on the estimation of continuous precipitation in a large area where the hourly rainfall exceeded 50 mm for more than two stations. It had the ability to estimate short-term heavy precipitation in areas lacking automatic stations.
文摘选用2013—2020年6—8月河北省中南部(冀中南)地区1115个自动站逐小时降水数据与地形高度资料,统计该地区夏季小时强降水(hourly heavy rainfall,HHR)和暴雨日的发生频次、持续时间、降水强度等方面的分布特征。结果表明:冀中南地区夏季发生频次为2.2~3.0次·a-1的HHR对降水贡献率大于35%,高频区有6个,在沧州东部沿海呈片状分布,在西部山区呈点状分布。小于60 mm·h^(-1)的HHR发生站次日变化特征为单峰、单谷,60 mm·h^(-1)以上发生站次随降水强度增大而锐减,日变化特征不明显。降水性质方面,冀中南地区的西部山区HHR高频区多积状云对流性降水,常发生在12:00—18:00;沧州东部沿海多受台风和切变线影响,HHR为降水强度较大的层状云和积状云混合性降水。
文摘Based on the data of hourly precipitation in 11 national stations and 262 regional stations in Ulanqab City from 2017 to 2022,the annual,monthly and daily variations of short-term heavy precipitation in Ulanqab City were statistically analyzed.The results show that the frequency of short-term heavy precipitation in Ulanqab City was high in the south and low in the north,and was closely related to the terrain.Short-term heavy precipitation in Ulanqab City was mainly concentrated from June to August,of which it was the frequentest in July.Short-term heavy precipitation mainly occurred from the afternoon to evening,and was concentrated from 13:00 to 20:00,especially at 19:00.The rainfall in Ulanqab City ranged mainly from 20 to 30 mm,accounting for 74.7%,and the rest accounted for 25.3%.
