基于蒙特卡罗方法的卫星光学波段闪电辐射观测模拟

我国下一代静止气象卫星风云四号将首次搭载光学闪电成像仪上天，对闪电和与之相联系的强对流天气进行实时、连续观测。对未来风云四号卫星闪电观测资料的特性进行预先研究，一个重要的途径就是建立光学波段的闪电辐射传输模拟算法，对闪电辐射的物理过程及卫星观测到的闪电辐射光学特征进行模拟研究。结合风云四号卫星闪电成像仪观测的几何和波长参数，在构建简化的闪电光源模型和雷暴云模型的基础上，利用蒙特卡罗随机模拟和光子追踪方法，模拟得到了风云四号卫星闪电成像仪观测到的云顶闪电信号，并对其辐射特征进行了初步研究。结果表明，基于蒙特卡罗方法的闪电辐射传输模拟，可以从理论上揭示卫星光学波段闪电辐射观测与最重要影响参数之间的联系，这将为未来星载闪电资料的应用提供非常有价值的信息。

Monte Carlo Radiative Transfer Modeling of Optical Lightning Signals Observed by Satellite

For the next generation of Chinese geostationary meteorological satellites (FY-4), an optical lightning mapping sensor is planned to observe lightning and storms on a real-time, continual basis. In order to fully benefit from FY-4 lightning observations，it is desirable to establish optical-band radiative transfer simulation algorithm of lightning, and investigate the properties of lightning radiative transfer and the cloud top radiation signals observed by satellite. Combined observational parameters of FY-4 lightning imager，based on the simplified lightning source and thunderstorm models, a Monte Carlo approach is applied for simulating the transfer of lightning produced photons in thunderclouds, and the outputs are designed to address the lightning radiation signatures obtained by FY-4 lightning mapping sensor. The simulated results show that lightning radiative transfer simulation based on Monte Carlo method can theoretically reveal links between satellite optical-band lightning radiation observation and the most important parameters, and provide extremely valuable information for the future application of lightning data observed by satellite.