陆面微波比辐射率的卫星观测研究进展

复杂多变的陆地表微波比辐射率，造成陆面上星载微波观测反演大气参数较为困难，也使得许多卫星微波资料不易同化应用到数值模式，因此迫切需要提供准确可靠的陆面微波地表比辐射率信息.随着卫星观测技术的迅速发展，利用丰富的星载被动微波观测直接反演陆面微波比辐射率成为一种主要手段.国外针对星载微波成像仪和微波垂直探测器开展较为系统的陆面微波比辐射率研究，建立不同类型的地表比辐射率反演方法，开发地表比辐射率参数化方法并应用于辐射资料同化.对于卫星观测反演陆面微波比辐射率存在的问题，开展了评估分析和方法订正.国内利用卫星观测也开展了一些陆面微波比辐射率研究工作，尚需要系统、综合的提炼.对于地表特征复杂的中国地区，还需要评估认识不同陆面微波比辐射率反演方法在我国适用情况，需要增强陆面微波比辐射率数据质量的认识以及业务应用.

Development of land surface microwave emissivity retrieval using satellite observations

Microwave surface emissivity over land is more complex and variable, resulting in more difficult in using microwave data to retrieval atmospheric parameters and assimilating microwave data into numerical model over land. Therefore, it is crucial to provide accurate microwave land surface emissivity over land. With rapid development of satellite observations, abundant passive microwave measurements directly from space have been widely used to retrieve microwave surface emissivity over land. Aim to more advanced microwave imagers and sounders on satellite, substantial works have been implemented to estimate microwave surface emissivity over land. Different types of surface emissivity retrieval methods are established, and the surface emissivity parameterization method is developed and applied to the satellite data assimilation. For the issues exist in currently emissivity retrieval using satellite observation, the related assessment on different retrieving methods and corrected method have been concerned. There are some works focusing on land surface microwave emissivity in domestic, however, it is lack of systemic and comprehensive study in a long run. In particular to the unique and complex land characteristic over China, it is necessary to enhance the understand of the performance of emissivity retrieval methods and the data quality of retrieved microwave surface emissivity as well as its operational application over land in China.