摘要
为了提高冰雹预报预警及防御能力,利用气象站常规观测和多普勒雷达探测等资料,采用气候倾向率法和天气学统计等方法,对2001—2022年沧州地区冰雹的气候变化特征及其形成的天气学机制和雷达回波特征进行了分析研究。结果表明:近22年来,沧州地区出现的冰雹灾害多是中小冰雹,且出现最早日期有明显推迟、最晚日期有明显提前的趋势。年降雹次数呈减少趋势,一年中冰雹高发时段集中在春季和初夏,其中6月份发生最多;一天中高发时段集中在12—19时。西北气流型和槽前型是沧州地区产生冰雹的主要天气形势。有利于沧州地区冰雹天气发生的环境参量综合如下:满足:(1)T_(85)≥28℃;(2)K/MK≥27℃;(3)LI/SI≤-0.8℃;(4)CAPE≥1000 J·kg^(-1),0℃层在2.8~5.1 km,-20℃层在5.2~8.0 km,或W_(sr)≥12 m·s^(-1),0℃层在2.1~3.6 km,-20℃层在4.7~6.5 km,925 hPa T-T_(d)≤6℃。沧州地区6—7月份冰雹雷达识别指标MCR、MVIL、DVIL均较河北省冰雹雷达识别指标阈值明显偏高,ET、H_(M)与河北省指标阈值相接近,而强回波伸展高度H_(MCR)≥H_(-20℃)。
In order to improve the ability of hail forecasting,early warning and defense,the characteristics of hail climate change,synoptic formation mechanism and radar echo in Cangzhou from 2001 to 2022 were analyzed by climatological tendency rate method and synoptic statistics method,based on conventional observation and Doppler radar data from weather stations.The results showed that:In the past 22 years,the hail disasters in Cangzhou were mostly small and medium-sized hail,and the earliest occurrence date was obviously delayed,while the latest date was obviously advanced.The annual hail frequency showed a decreasing trend.Hails occurred mostly in spring and early summer,especially in June,and occurred more frequently during 12:00 to 19:00.The northwest airstream and pre-trough were the main weather patterns causing hail in Cangzhou.The environmental parameters favorable to the occurrence of hail in Cangzhou were summarized as follows:(1)T_(85)≥28℃;(2)K/MK≥27℃;(3)LI/SI≤-0.8℃;(4)When CAPE≥1000 J·kg^(-1),0℃ layer was at 2.8~5.1 km height,-20℃ layer was at 5.2~8.0 km height,or when W_(sr)≥12 m·s^(-1),0℃ layer was at 2.1~3.6 km height,-20℃ layer was at 4.7~6.5 km height,T-Ta≤6℃ at 925 hPa.In June and July,the thresholds of hail radar identification indexes MCR,MVIL and DVIL in Cangzhou were obviously higher than those in Hebei province,while ET and Hm were close to those in Hebei province,and the extension height of strong echo H_(MCR)≥H_(-20℃).
作者
秦俊灵
任妙春
牟凤军
张唯
Qin Junling;Ren Miaochun;Mu Fengjun;Zhang Wei(Cangzhou Meteorological Bureau,Hebei Cangzhou 061001)
出处
《内蒙古气象》
2024年第2期10-16,共7页
Meteorology Journal of Inner Mongolia
基金
河北省气象局科研项目(22ky14)。
关键词
冰雹
气候特征
天气背景
环境参量
雷达指标
Hail
Climatic characteristic
Weather background
Environmental parameters
Radar indicators
