海洋水汽信息不仅是研究海洋动力环境和天气系统演化的重要参数，也是海洋二号卫星（HY-2A）星载雷达高度计和微波散射计实时数据处理和高精度应用的关键因子，在HY-2A观测要素中非常关键；因此，为保证HY-2A水汽信息的准确度和可靠性，对其外部校核和精度评估十分必要。本项目基于全球分布的陆基和大洋船载GNSS气象信息、以及多年的HY-2A水汽资料，重点解决HY-2A星下点与GNSS气象站点的匹配方式、近岸亮温及水汽污染修正方法、局域水汽同化方法等校核关键问题，评估HY-2A水汽产品精度，探索HY-2A水汽校核值的时空变化特性，构建HY-2A水汽信息高精度、动态、全球海洋适用的校核模型，提升HY-2A全球海洋水汽产品的可靠性和准确度，保障卫星水汽产品的气象应用和卫星测高数据的精确度，也为即将发射的HY-2B等系列卫星及其它海洋卫星的水汽评估和标校提供参考。

The water vapor content is the vital observing element in the HY-2A satellite. It is the significant parameter for exploring the marine dynamic environment and the synoptic system evolution, but also the key factor for the real-time data processing and high-precision application of the radar altimeter and the microwave scatterometer. Therefore, it plays an important role on the precise assessment and external calibration method for the water vapor content of the HY-2A satellite. .Based on the global ground-based and shipborne GNSS/MET data source together with HY-2A water vapor products, this project firstly focus on the matching mode of HY-2A satellite foot and GNSS/MET sites, the correcting pollution problem of the brightness temperature and water vapor content on the nearshore, and the water vapor assimilation. After evaluating the accuracy of HY-2A water vapor products and exploring the temporal and spatial variation character of its calibration values, a global and dynamic water vapor calibration model will be finally built and assessed for HY-2A satellite. This model will be beneficial to improving the stability and accuracy for HY-2A ocean water vapor products, and guaranteeing the meteorological and marine application of satellite products. Furthermore, this research will back the water vapor products assessment and calibration for the upcoming HY-2B satellites and other ocean satellites.