基于2024年成都后汛期雷暴初生预报研究
Research on Thunderstorm Initiation Prediction during the Late Flood Season of 2024 in Chengdu

本研究采用多源气象观测数据融合的分析方法，重点探究了雷暴形成初期对流云团的动力热力特征及其演变规律。研究基于中国气象局的地面自动气象站、探空站等常规观测数据，结合日本气象厅新一代静止气象卫星葵花9号的高时空分辨率遥感资料，采用卫星云图的单通道阈值检测算法，配合多光谱通道协同分析技术，对2024年成都地区后汛期发生的两次典型强对流天气过程中的云团初生阶段进行了系统性观测研究。通过整合地基观测与天基遥感的多维度数据，重点分析了初生对流云团的光谱通道特征及其与强降水过程的对应关系。研究结果显示：(1) 雷暴天气从初生至成熟阶段历时短，天气尺度小，伴随的每小时降水大多在20 mm以上，极端情况下每小时可达到55 mm以上。(2) 单通道阈值法识别的初生云团的云顶亮温值位于200 K至240 K，随时间推移呈下降趋势，当云顶亮温低于235 K的阈值时，雷暴天气发生。(3) 多通道协同方法下的雷暴云团在红外–分裂窗和红外–水汽通道的亮温差，在对流中心附近15~30 km的占比随时间显著增加，当红外–分裂窗通道亮温差位于0.5~5 K之间时，降水量增大且雷暴天气发生。(4) 云有效半径的增大和云光学厚度的减小，表明雷暴云团从初生往成熟期过渡，是提前预警的关键时刻，云有效半径超过30 μm，以及云光学厚度低于28时，雷暴天气发生概率增加，初生云团云顶高度持续抬升至9~13 km，同时云顶温度下降，皆与对流发展密切相关。通过研究雷暴云团初生阶段的对流云发展规律及其演变特征，对于提高成都地区及全国范围的气象预警准确性具有重要价值。这不仅有助于减少极端天气对公共安全和工农业生产的影响，还能为防灾减灾工作提供科学依据。
This study employs a multi-source meteorological observation data fusion approach to investigate the dynamic-thermal characteristics and evolutionary patterns of convective cloud clusters during the initial stages of thunderstorm formation. The research integrates conventional observation data from the China Meteorological Administration’s surface automatic weather stations and radiosonde observations with high spatiotemporal resolution remote sensing data from the Japan Meteorological Agency’s next-generation geostationary satellite Himawari-9. Using a single-channel threshold detection algorithm for satellite cloud imagery combined with multispectral channel correlation analysis technology, we conducted systematic observational research on the genesis phase of cloud clusters during two typical severe convective weather events occurring in the late flood season of 2024 in the Chengdu region. By synthesizing multi-dimensional data from ground-based and space-based observations, we focused on analyzing the spectral channel characteristics of incipient convective clouds and their correlation with heavy precipitation processes. Key findings include: (1) Thunderstorm events exhibited rapid development from initiation to maturity with mesoscale features, typically producing hourly precipitation exceeding 20 mm and reaching over 55 mm in extreme cases. (2) Cloud-top brightness temperature (BT) of developing clouds identified by the single-channel method ranged 200~240 K, showing a decreasing trend, with thunderstorms triggered when BT fell below 235 K. (3) In multispectral analysis, the brightness temperature difference (BTD) between infrared