摘要
强对流天气引发的灾害是甘肃省最主要的自然灾害,已严重威胁人民群众的生命财产安全。本文利用甘肃省2013-2019年1716个自动观测站的小时雨量资料以及80个国家气象站1990-2019年冰雹和1990-2013年雷暴大风观测资料,分析了甘肃省短时强降水、冰雹和雷暴大风的时空分布特征。结果表明:甘肃省短时强降水与山脉地形密切相关,有3个高发中心,主要位于陇南山地和陇东黄土高原丘陵沟壑区;不同强度短时强降水年际变化特征明显,20~30 mm·h-1强降水占79.0%;短时强降水主要出现在4~9月,8月最多;日变化特征明显,高发时段在17:00-02:00。近30年甘肃省冰雹和雷暴大风日数均呈明显减少趋势。冰雹空间分布特征与地形密切相关,有3个高发区和3个高发点,主要出现在青藏高原边坡和高海拔地区,大部地区以中等强度冰雹为主。降雹季节性强,雹日高度集中,5~7月为高发时段,占全年的62.6%;日变化特征明显,午后13~19时为高发时段,占全天的88.5%。降雹持续时间主要集中在8 min以内,不同持续时间冰雹发生次数呈先增加后减少特征,2~4 min出现次数最多。雷暴大风以一般雷暴大风为主,强雷暴大风仅占5%,空间上呈现山地、高原多的特点,一年之中主要集中出现在5~9月,占全年的86.6%,一日之中主要出现在午后(15:00-21:00),占全天的83.7%。
The disasters caused by severe convective weather are the most important natural disasters in Gansu Province,which has seriously threatened in the lives and property of the people.Based on the hourly rainfall data of1716 observation stations from 2013 to 2019 in Gansu Province,the hail data of 80 national meteorological stations from 1990 to 2019 and thunderstorm gale data from 1990 to 2013,the temporal and spatial distribution characteristics of short-term heavy precipitation,hail and thunderstorm gale in Gansu Province were analyzed.The results show that:short term heavy rainfall is closely related to mountain terrain,there were three high incidence centers in Gansu Province,which were mainly located in the mountainous area of South Gansu and the hilly and gully area of Loess Plateau of East Gansu.The interannual variation characteristics of short-term heavy rainfall with different intensities were obvious,with 20~30mm·h-1heavy rainfall accounting for 79.0%;the short-term heavy rainfall mainly occurs from April to September,with the most in August;the diurnal variation characteristics were obvious,and the high incidence period was from 17:00 to 02:00.In recent 30 years,the number of days of hail and thunderstorm gale in Gansu Province showed an obvious decreasing trend.The spatial distribution characteristics of hail in Gansu Province were closely related to the terrain.There were three high incidence areas and three high incidence points,which mainly occur in the slopes of the Qinghai Tibet Plateau and high-altitude areas.Most of the areas were dominated by moderate intensity hail.The hail was seasonal and highly concentrated,with high incidence period from May to July,accounting for 62.6%of the whole year;the daily variation was obvious,with high incidence period from 13:00 to 19:00 in the afternoon,accounting for 88.5%of the whole day.The hail duration is concentrated in 8 minutes,the frequency of hail in different duration was increased firstly and then decreased,and the frequency of 2~4 minutes was more often than any other values.The thunderstorm gales were general in majority,the severe thunderstorm gales accounted for only 5%.The distribution of thunderstorm gales was characterized by many mountains and plateaus,mainly occurring from May to September,accounting for 86.6%of the whole year,in the daytime,they are mainly concentrated in the afternoon(15:00-21:00),accounting for 83.7%of the whole day.
作者
谭丹
黄玉霞
沙宏娥
TAN Dan;HUANG Yuxia;SHA Hong'e(Lanzhou Central Meteorological Observatory,Lanzhou 730020,China)
出处
《自然灾害学报》
CSCD
北大核心
2022年第2期222-232,共11页
Journal of Natural Disasters
基金
国家自然科学基金项目(41705062)
中国气象局气象预报业务关键技术发展专项(YBGJXM(2020)1A-07)
甘肃省气象局创新团队(GSQXCXTD-2020-01)。
关键词
短时强降水
冰雹
雷暴大风
时空分布
甘肃省
short-time heavy precipitation
hail
thunderstorm gale
spatial-temporal distribution
Gansu Province
作者简介
谭丹(1987-),女,高级工程师,主要从事天气预报与西北强对流天气研究.E-mail:lz_tdian@163.com
