基于FY-4A AGRI数据研究2023-02-06土耳其地震水汽异常变化

Research on Water Vapor Anomaly of 2023-02-06 Türkiye Earthquakes Based on FY-4A AGRI Data

首先利用探空数据对风云四号气象卫星A星(FY-4A)先进的静止轨道辐射成像仪(AGRI)提供的水汽产品进行精度验证;然后利用AGRI获取2023-02-06土耳其地震震中区域水汽、陆表温度和降水估计的时间序列,并对水汽异常变化特征进行分析。结果表明:1) AGRI水汽和探空水汽的相关系数为0.90,RMSE和平均bias分别为2.51 mm和-0.06 mm;2)临震时,AGRI水汽方差上升至0.029-0.156 mm,波动加剧;震后,AGRI水汽出现一个明显的陡升-陡降过程;3)基于AGRI陆表温度和降水估计,推断出现水汽异常变化的原因可能是地震后地面热作用增加使得水汽上升,在峰值时形成降水,导致水汽急剧下降。

We first verify the accuracy of water vapor products provided by the FY-4A satellite advanced geostationary radiation imager(AGRI)using radiosonde data.Then,we analyze the characteristics of water vapor anomaly changes using water vapor,land surface temperature and quantitative precipitation estimation provided by AGRI in the epicenter region of 2023-02-06 Türkiye earthquakes.The results show that:1)The correlation coefficient between AGRI water vapor and radiosonde water vapor is 0.90,and the RMSE and mean bias are 2.51 mm and-0.06 mm respectively.2)Prior to the earthquake,the variance of AGRI water vapor increased to 0.029~0.156 mm,with intensified fluctuations.After the earthquake,AGRI water vapor exhibited a distinct sharp rise and fall process.3)Using the AGRI land surface temperature and quantitative precipitation estimation of AGRI data,we estimate that the reason for the water vapor anomaly may be that the increased thermal action of the ground after the earthquake caused water vapor to rise and form precipitation at the peak,resulting in a sharp drop in water vapor.