GNSS约束的MERSI/FY-3A PWV校准方法EI北大核心CSCD

精确的水汽信息对于短临天气预警和长期气候监测具有重要意义。本文针对搭载在我国第2代极轨卫星风云三号A星(FY-3A)上中分辨率光谱成像仪(medium-resolution spectral imager,MERSI)获取水汽精度较低的现状,提出一种GNSS约束的MERSI/FY-3A PWV校准方法。首先,对MERSI/FY-3A的PWV段产品进行处理得到水汽日产品,并利用GNSS和无线电探空(radiosonde,RS)数据对其进行评估;然后,根据PWV的季节分布特性,构建GNSS约束的MERSI/FY-3A PWV季节自适应校准模型;最后,分别利用GNSS、RS和再分析资料对校准后的MERSI/FY-3A水汽进行对比,验证提出方法的有效性。研究表明:本文提出的PWV校准方法,能够有效改善MERSI/FY-3A水汽日产品和旬产品的精度,改善率分别为58.63%和68.72%。该方法可为遥感水汽快速校准研究提供重要的理论依据。

The MERSI/FY-3A PWV correction method based on GNSS

Accurate water vapor information is of great importance for short-range weather warnings and long-term climate monitoring.A MERSI/FY-3A PWV correction method is proposed in this paper to address the low water vapor accuracy obtained by the Medium-Resolution Spectral Imager(MERSI)of the second generation of Chinese polar-orbit meteorological satellite FY-3A.Firstly,the daily product data were obtained by processing the 5 min product of MERSI/FY-3A and evaluated by using ground-based GNSS and Radiosonde data in China;then,according to the seasonal distribution of PWV,the GNSS-based PWV seasonal calibration model is constructed;finally,a comparison of the calibrated MERSI/FY-3A PWV using Radiosonde data was performed to verify the validity of the proposed method.The results show that the proposed PWV seasonal calibration correction model can effectively improve water vapor accuracy in MERSI/FY-3A 5 min and 10 days products,with an improvement rate of 58.63%and 68.72%,respectively.This method can provide a theoretical foundation for the rapid correction of water vapor in remote sensing.