风云卫星的掩星干大气温度廓线精准度特征  

Accuracy and Stability of Radio Occultation Dry Temperature Profiles from Fengyun Satellites

作　　者：廖蜜 张鹏 刘健[1,2,3] 柳聪亮 白伟华[4] 徐娜[1,2,3] 陈林 Liao Mi;Zhang Peng;Liu Jian;Liu Congliang;Bai Weihua;Xu Na;Chen Lin(National Satellite Meteorological Center/National Center for Space Weather,Beijing 100081;Innovation Center for Fengyun Meteorological Satellite,Beijing 100081;Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites,CMA,Beijing 100081;National Space Science Center,Chinese Academy of Sciences,Beijing 100190)

机构地区：[1]国家卫星气象中心/国家空间天气监测预警中心,北京100081 [2]许健民气象卫星创新中心,北京100081 [3]中国气象局中国遥感卫星辐射测量和定标重点开放实验室,北京100081 [4]中国科学院国家空间科学技术中心,北京100190

出　　处：《应用气象学报》2023年第3期270-281,共12页Journal of Applied Meteorological Science

基　　金：国家重点研发计划(2022YFF0801302,2021YFC2803303);中国科学院青年交叉团队项目(JCTD-2021-10)。

摘　　要：风云三号气象卫星C星/D星/E星的掩星接收机接收GPS和北斗导航卫星信号,形成掩星事件,进而反演得到大气温度廓线。利用2016—2022年FY-3C/3D/3E GPS和北斗掩星干大气温度廓线,通过与ERA5再分析资料对比,分析掩星干大气温度的精准度特征。结果表明:掩星干大气温度廓线在200 hPa至20 hPa间精度最高,标准偏差约为1 K,且GPS与北斗掩星的误差特征相近。在稳定度方面,FY-3C GPS掩星干大气温度平均偏差线性变化趋势为-0.0055 K·a^(-1),与国外同类掩星资料稳定性相当。因2021年初掩星天线多径效应订正,FY-3D GPS掩星干大气温度与ERA5再分析资料的平均偏差出现明显跳变,平均偏差值从-0.154 K降为-0.007 K,负偏差显著减小。总体上,FY-3C GPS掩星干大气温度廓线长序列稳定度较好,北斗掩星干大气温度廓线精度能够达到或优于GPS,风云极轨卫星序列的GPS和北斗掩星在长序列稳定性上具有良好的应用前景。The earth's climate has undergone significant changes due to the combined effects of natural changes and human activities.To understand the impact of climate change,the most fundamental work is to establish high-quality data required for climate purposes.Currently,the long series observations mainly come from satellites and sites.However,most satellite sensors are designed for short-term and imminent weather monitoring and numerical prediction,rather than long-term climate monitoring.To meet future research needs,more efforts are needed in data reprocessing such as satellite calibration and multi-source data fusion.Global Navigation Satellite System Radio Occultation(GNSS-RO)is a system that carries a receiver on low orbit satellite to receive radio signals transmitted by the global navigation satellite system.GNSS-RO detects the earth's atmosphere in a borderline manner during relative motion.When propagating in non-vacuum atmosphere,radio signals may appear bent or delay due to different atmospheric physical characteristics.After complex processing,physical parameters such as atmospheric temperature,humidity,and density can be inverted.Each receiver observes approximately 500 occultation events per day,which are almost randomly distributed on the earth and not affected by clouds and underlying surfaces.These data provide a source of observational information with high vertical resolution and long-term stability,extending from near surface to upper stratosphere.The original occultation observation is based on time and position measurements,needing no calibration,which has advantages in climate change study.The occultation receiver on FY-3C/3D/3E meteorological satellite can receive GPS and Beidou Navigation Satellite System(BDS)signals,and the records are almost nine years long.To analyze the accuracy and stability of temperature records from multiple radio occultation,the mean and standard deviation of the dry temperature of FY-3C/3D/3E GPS and BDS radio occultation are studied using ERA5 data.It demonstrats th

关 键 词：风云掩星 北斗 温度 时间序列变化 

分 类 号：P414.4[天文地球—大气科学及气象学]