新一代静止气象卫星葵花8号的晴空红外辐射率资料同化对台风“天鸽”的预报影响研究

本文以2017年第13号台风“天鸽”（Hato）为例，在WRFDA同化系统中结合日本葵花8号（Himawari-8）资料，通过同化Himawari-8晴空红外辐射率资料并进一步考察其对台风“天鸽”的结构、强度、路径分析和预报的影响。研究结果表明:同化Himawari-8晴空红外辐射率资料对台风背景场的水汽相关变量分析有显著改进，对背景场中的台风水汽信息有一定的改进作用。与控制实验，即没有同化Himawari-8晴空红外辐射率资料的实验相比，加入同化实验对台风“天鸽”的风场、500 hPa气压场的分析效果有所提高，台风气旋性环流加强，并进一步改进了对台风“天鸽”的路径、台风中心最低气压和近中心最大风速的预报。平均路径误差和降水预报相对于常规观测变量的均方根误差均有所改善。

The impact of assimilation of Himawari-8 clear-sky data from the new generation geostationary meteorological satellite on the forecast of super Typhoon Hato

Based on the Typhoon Hato in 2017, the Himawari-8 AHI infrared radiance data are assimilated under the clear-sky condition in WRFDA system to investigate its impact on the typhoon forecast. The structure, strength, as well as the track forecasts are also studied for the Typhoon Hato. The results show that the clear-sky assimilation of Himawari-8 infrared radiance data provides obvious increment of cyclonic winds in the typhoon core and an obvious increase of typhoon in background field. Compared with the control experiment without assimilating Himawari-8 AHI infrared radiance data, the experiment that assimilates Himawari-8 AHI data strengthens the wind field of Typhoon Hato, 500 hPa pressure field analysis, and typhoon cyclonic circulation. In addition, the AHI radiance assimilation further improves the forecast of track, minimum sea level pressure, and the maximum wind speed of the Typhoon Hato. The average track error, the precipitation distribution, the root mean square error against the conventional data are also improved.