热带气旋快速加强与海表温度分布统计特征研究

为加强海表温度对热带气旋快速加强影响的认识，利用中国气象局上海台风研究所整编的热带气旋最佳路径数据集和欧洲中尺度天气预报中心提供的海温数据，选取1979−2019年期间的西北太平洋热带气旋，统计分析了海温和热带气旋强度快速变化的特征。研究结果表明：（1）约90%的热带气旋快速加强发生在夏季和秋季，分别占快速加强总次数的32.8%和56.4%，绝大部分热带气旋以跨越1个强度等级的快速加强为主，由强热带风暴快速加强到台风和由台风快速加强到强台风是出现次数较多的两种情况。（2）夏季大于28℃，秋季大于27.5℃的海表温度条件有利于热带气旋快速加强，较低强度等级的热带气旋需要更高的海表温度（> 29℃）才易出现快速加强；热带气旋快速移动有利于其中心处海温维持较高状态。（3）海温的时间变率在±0.2℃/(6 h)内，水平空间梯度低于0.4℃/(°)是热带气旋快速加强的有利条件；热带气旋强度越强，越需要平稳的海表温度环境。（4）热带气旋处于强热带风暴及以上级别时，仅利用海表温度条件对其是否发生快速加强的判断准确性较好。这一工作量化了有利于热带气旋加强的海表温度环境，为业务上基于海表温度定量预报热带气旋强度演变提供了一种技术参考。

An analysis of tropical cyclones rapid intensification and the statistical characteristics of sea surface temperature distribution

To better understand the influence of sea surface temperature (SST) on tropical cyclones rapidly intensifying, the characteristics of rapid changes in sea surface temperature and intensity of tropical cyclones in the western North Pacific during 1979−2019 were statistically analyzed using the tropical cyclones best track data compiled by the Shanghai Typhoon Research Institute of the China Meteorological Administration and the sea surface temperature data provided by European Centre for Medium-Range Weather Forecasts. The results indicate the following: (1) About 90% of the rapid intensification of tropical cyclones occurred in summer and autumn, accounting for 32.8% and 56.4% of the total number of rapid intensification respectively. Most tropical cyclones are dominated by rapid intensification across one intensity level, rapid intensification from a severe tropical storm to a typhoon and rapid intensification from a typhoon to a severe typhoon are the two conditions that occur more frequently. (2) The SST conditions greater than 28℃ in summer and 27.5℃ in autumn are conducive to the rapid intensification of tropical cyclones. Lower intensity of tropical cyclones require higher SST (> 29℃) for rapid intensification. The faster translation speed of tropical cyclones is conducive to maintaining high SST environment at its center. (3) When the time variation of SST is within ±0.2℃/(6 h), the horizontal spatial gradient is less than 0.4℃/(°), which is the favorable condition for the rapid intensification of tropical cyclone; the stronger the tropical cyclone is, the more stable the SST environment is needed. (4) When tropical cyclone is a severe tropical storm or above, it is better to judge whether rapid intensification occurs by using only the SST conditions. This work quantifies the SST environment conducive to tropical cyclone intensification and provides a technical reference for quantitative prediction of tropical cyclone intensity evolution based on SST.