摘要: |
为了更好地监测预警江西袁河流域强降水天气,使用江西雨量资料、欧洲中心格点(1°×1°)再分析资料和江西雷达回波等资料,对袁河流域5次大暴雨过程进行分析,结果表明:(1)袁河流域强降水天气形势场是925~700 hPa切变线、低层辐合高层辐散中心、西南气流达到12~18 m·s-1等因素影响;T-LnP图上整层水汽充沛,可降水量在75 mm以上;降水前低层累积不稳定能量CAPE(1000 J/Kg)和对流抑制能CIN(100 J/Kg)。(2)强降水回波的组合反射率CR在50 dBz左右,回波顶高在13 km左右,垂直积分液态水含量在12 kg·m2左右;40 dBz回波顶高在6~7 km,45 dBz回波顶高在6.5 km以下。(3)强降水和回波强度dBZ成正相关,随降水的增强,回波明显增强;当回波强度≤20 dBz时,雨强几乎不变;当回波强度在20~35 dBz之间,雨强随回波强度增加而缓慢加大;当回波强度在35~50 dBz之间,雨强随回波强度加大明显增加;而当回波强度≥50 dBz时,雨强反而趋于下降或维持。研究结果对袁河流域强降水的监测预警和预报服务有指导意义。 |
关键词: 袁河流域;强降水;天气系统;回波特征;相关分析 |
DOI: |
投稿时间:2022-04-10修订日期:2022-08-31 |
基金项目:中国科学院战略性先导科技专项(A类-XDA19040202);国家自然科学基金项目(41975001);江西省气象科技项目面上项目(JX2021M12):袁河流域大暴雨短时强降水特征分析。 |
|
Analysis of weather background and echo characteristics of heavy precipitation in Yuanhe River Basin |
mazhongyuan |
(Jiangxi Institute of Meteorological Sciences) |
Abstract: |
In order to better monitor and warn the heavy precipitation weather in Yuanhe River Basin, Jiangxi rainfall data, European Central grid (1 * 1) reanalysis data and Jiangxi radar echo data are used to analyze five heavy rainstorm processes in Yuanhe River Basin. The results show that: (1) the heavy precipitation weather situation field in Yuanhe River Basin is affected by 925~700 hPa shear line, low-level convergence, high-level divergence center, southwest air flow reaching 12~18 m·S-1 and other factors; On the T-lnP map, the whole layer has abundant water vapor, and the precipitable water is more than 75 mm; Accumulated instability energy CAPE (1000 J/kg) and convective suppression energy CIN (100 J/kg) in the lower layer before precipitation. (2) The combined reflectivity CR of heavy precipitation echo is about 50 dBZ, the echo top height is about 13 km, and the vertical integrated liquid water content is about 12 kg/m2; The top height of 40 dBZ echo is 6~7 km, and the top height of 45 dBZ echo is less than 6.5 km. (3) There is a positive correlation between heavy precipitation and echo intensity dBZ, and the echo increases obviously with the increase of precipitation; When the echo intensity is ≤ 20 dBZ, the rain intensity is almost unchanged; When the echo intensity is between 20~35 dBZ, the rain intensity increases slowly with the increase of echo intensity; When the echo intensity is between 35~50 dBZ, the rain intensity increases significantly with the increase of echo intensity; When the echo intensity is ≥ 50 dBZ, the rain intensity tends to decrease or maintain. The research results have guiding significance for the monitoring, early warning and prediction service of heavy precipitation in Yuanhe River Basin. |
Key words: Yuanhe River Basin; Heavy precipitation; Weather system; Echo characteristics; correlation analysis |