利用FY-3C卫星GNSS掩星数据分析中国区域对流层顶参数变化

使用FY-3C气象卫星GNSS掩星数据反演得到2017-03-01～2018-02-28大气温度廓线，并估计对流层顶高度变化；然后利用探空气球数据和ERA5模型数据进行验证；最后以2°×2°的空间分辨率将中国区域划分为608个网格，针对每一个单元格，分别计算对流层顶参数，建立格网模型，分析中国区域对流层顶参数的时空分布特征。结果表明，对流层顶参数随纬度具有明显的分带特征，在经度上变化并不明显，表现为南北区域不对称、东西区域较为对称的现象；对流层顶参数具有明显的季节性变化特征。

Variations of Tropopause Parameters over China from FY-3C GNSS Radio Occultation Observations

We use the GNSS occultation data of Fengyun 3C meteorological satellite independently developed by China to retrieve the atmospheric temperature profile from March 1, 2017 to February 28, 2018. We estimate tropopause height change and verify it using the sounding balloon data and ERA5 model data. With a spatial resolution of 2°×2°, China is divided into 608 cells according to latitude and longitude. For each cell, we calculate the tropopause parameters, and a grid model is established to analyze the temporal and spatial distribution characteristics of tropopause parameters in China. The results show that the tropopause parameters have obvious zonation characteristics with latitude, but not obvious change in longitude, which shows that the north-south region is asymmetric, and the east-west region is more symmetrical. The tropopause parameters have obvious seasonal characteristics.