Data quality control with multi-source information for FY-3 microwave sounder observations

摘要

Launched in 2013, and 2017 respectively, Chinese Fengyun-3C and 3D meteorological satellites are equipped with twomicrowave sounders, Microwave Temperature Sounder (MWTS) and Microwave Humidity Sounder -2 (MWHS-2),whose observations play an important role in numerical weather prediction by data assimilation. Data quality controlshould be carried out before assimilation to filter out bad data, such as cloud- or rain-polluted data and questionable data.This work can’t be accomplished purely depending on MWTS or MWHS-2 themselves. MWHS-2 is taken as anexample to do quality control in the paper, and the method is suitable for MWTS too. Multi-source information fromother instruments onboard FY-3 is extracted to assist in the work. Cloud mask product from VIRR (Visible and InfraRedRadiometer), oceanic cloud liquid water content product from MWRI (Microwave Radiation Imager), and global rainrate product from MWRI are mapped to MWHS-2 for quality control in combination with oceanic rain detection productfrom MWHS-2 itself. 6 kinds of cloud and rain detection schemes are then designed to get the best choice by analyzingthe characteristics of background departure. RTTOV v10 is adopted to simulate brightness temperature of MWHS-2 atall channels. The results suggested that scheme RI RC (MWRI cloud and rain information ingested) and scheme RC (allinformation ingested) are the two best choices for numerical assimilation application, and scheme RI RC can retain moresamples. Questionable data can also be found in the way to help monitor the operational status of instruments.