源星载微波传感器在台风“小犬”强度和风场结构分析中的应用研究

Application of intensity and wind structure analysis of Typhoon KOINU based on multi-source spaceborne microwave sensors

中文关键词:  多源星载微波传感器台风“小犬”强度和风场结构提取研究

英文关键词:Typhoon, Typhoon wind radii, Radius of maximum  wind, Synthetic aperture radar, Spaceborne  microwave radiometer

中文摘要:

      星载微波传感器可以穿透云雾对海面10m高度风场进行全天时、全天候和大范围的直接观测，这为台风强度和风场结构的变化监测提供了契机。本文以2023年超强台风“小犬”为研究对象，基于主动式星载合成孔径雷达（SAR）和被动式微波辐射计提供的长时序观测资料，在风暴生命周期内对台风强度（MSW）、最大风速半径（RMW）和风圈半径等信息进行识别，并利用国际气候管理最佳轨迹档案（IBTrACS）数据集和中央气象台（NMC）实况资料进行验证。结果表明，利用星载微波传感器提取的台风强度与IBTrACS记录强度具有良好的一致性，两者均方根误差（RMSE）为3.8m/s，相关系数达0.91。同样地，基于卫星提取的RMW与IBTrACS资料也具有较好的一致性，两者RMSE为6.12km。对于风圈半径，卫星提取的7级（R7）、10级（R10）和NMC实况资料的RMSE分别为102km，43km和35km。对于台风“小犬”这类具有长生命周期的风暴，本文证明了主动式星载SAR、被动式辐射计高分辨率和多时段联合观测，对于精细化台风风场监测及其强度和结构的变化研究具有重要价值。

英文摘要:

      The spaceborne microwave sensor can penetrate clouds and fog to directly measure the 10m ocean sea surface wind field in any weather condition and at any time with a wide swath. These advantages provide an opportunity for monitoring the variation of f typhoon intensity and wind field structure. Taking Super Typhoon Koinu (2023) as the research object, this paper estimated the typhoon intensity, radius of maximum wind (RMW) and wind radii from the long time series measurements of active spaceborne synthetic aperture radar (SAR) and passive microwave radiometer data. The International Best Track Archive for Climate Stewardship (IBTrACS) data and National Meteorological Center real time meteorological data are used to validate our retrieval result. The results indicate that typhoon intensities estimated form spaceborne microwave sensor are in better correspondence with IBTrACS reports, with a higher correlation of 0.91 and RMSE of 3.8 m/s, respectively. Similarly, satellite-estimated radius of maximum wind (RMW) was in good agreement with IBTrACS data, with a RMSE of 6.12 km. For wind radii, the RMSE between satellite-estimated and NMC data are 102 km (R7, radius of Gale-force wind), 43 km (R10, radius of damaging-force wind) and 35 km (R12, radius of destructive-force wind), respectively. Moreover, for a TC with a long lifecycle, such as Typhoon Koinu (2023), we demonstrate that the high-resolution and multitemporal synergistic observations from SAR and radiometer are valuable for studying fine-scale features of the wind field and the evolution of typhoon intensity and wind structure.