红外与毫米波学报2023，Vol.42Issue(6)：834-844,11.DOI:10.11972/j.issn.1001-9014.2023.06.017
新息增量法评估FY-3E/HIRAS-Ⅱ观测质量
Evaluation of observation quality of FY-3E/HIRAS-Ⅱ using the innovation vector method
摘要
Abstract
FY-3E/HIRAS-Ⅱ is the first early mooring orbiting infrared hyperspectral instrument in the world.Evaluating the quality of its observation data plays a very important role in improving the data assimilation and the accuracy of global numerical weather prediction.Based on the 35 days of HIRAS-Ⅱ observations from December 2021 to January 2022 and March 2022,this paper uses the innovation vector method to assess the quality of the on-orbit observation data.The dis-tribution characteristics of O-B deviation and standard deviation are calculated by land and ocean respectively.Further matching MetOp-B/IASI observation data in the same time period and in the same region,the double-difference method is used to analyze the quality of HIRAS-Ⅱ observation data,which can eliminate the influence of radiation transfer mode simulation deviation.The results show that the O-B average deviation of long wave and medium wave in most channels is less than 0.5 K,and the standard deviation is within 1 K.The standard deviation on land is larger than that on ocean(especially for window channels).Due to the deviation of ERA5 reanalysis data,the radiation value simulated by RT-TOV has a systematic error in the 664-665 cm-1 CO2 absorption band and the 1 300-1 680 cm-1 water vapor absorption band,which makes the deviation larger,and the double O-B bias in these bands compared with MetOp-B/IASI is close to 0 K,indicating that the O-B bias is mainly caused by the simulation error of the radiation transfer mode,rather than the low quality of the instrument observation.The large deviation near the 980-1 080 cm-1 O3 absorption band and the 1 300 cm-1 CH4 absorption band is caused by the use of fixed climate profile values in RTTOV.The O-B average deviation of short wave in most channels is between-2 K and 2 K,and the standard deviation is within 2 K.The channels near 1 920 cm-1 are the junction of medium wave and short wave of the instrument,so different detectors will cause large O-B devia-tion.The large deviation of 2 267-2 380 cm-1 due to the fact of the NLTE effect(Non-local Thermodynamic Equilibrium)is not taken into account when RTTOV simulates the brightness temperature.The deviation and standard deviation of channels greater than 2 400 cm-1 increase gradually due to solar pollution.HIRAS-Ⅱ O-B deviation is asymmetric with the scanning angle,so it is necessary to correct the scanning angle deviation when using HIRAS-Ⅱ data.关键词
FY-3E/HIRAS-Ⅱ/RTTOV/新息增量法/观测质量评估Key words
FY-3E/HIRAS-Ⅱ/RTTOV/innovation vector method/evaluation of observation quality分类
数理科学引用本文复制引用
陈宏涛,官莉..新息增量法评估FY-3E/HIRAS-Ⅱ观测质量[J].红外与毫米波学报,2023,42(6):834-844,11.基金项目
国家自然科学基金(41975028) Supported by the National Natural Science Foundation of China(41975028) （41975028）
