Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system

Abstract Radiance data from satellite microwave radiometers are becoming increasingly important in the assimilation of numerical prediction systems. FengYun‐3E (FY‐3E), which was launched in July 2021, as the first early morning orbital satellite among FY‐3 polar‐orbiting meteorological satellite se...

Full description

Bibliographic Details
Main Authors: Hongyi Xiao, Wei Han, Peng Zhang, Yihong Bai
Format: Article
Language:English
Published: Wiley 2023-05-01
Series:Meteorological Applications
Subjects:
Online Access:https://doi.org/10.1002/met.2133
_version_ 1797792370603851776
author Hongyi Xiao
Wei Han
Peng Zhang
Yihong Bai
author_facet Hongyi Xiao
Wei Han
Peng Zhang
Yihong Bai
author_sort Hongyi Xiao
collection DOAJ
description Abstract Radiance data from satellite microwave radiometers are becoming increasingly important in the assimilation of numerical prediction systems. FengYun‐3E (FY‐3E), which was launched in July 2021, as the first early morning orbital satellite among FY‐3 polar‐orbiting meteorological satellite series, can greatly enhance the atmospheric sounding capacity in three orbits compared with the two‐orbit system that is distributed in morning or afternoon orbit. Focusing on MicroWave Humidity Sounder‐2 (MWHS‐II) onboard it, the schemes for thinning, quality control, bias correction and observational error calculation are developed. The scan‐position‐dependent biases are assessed in each channel and increasing biases near the edges of scanline are found in several temperature‐sounding channels. The data quality is compared with four analogous instruments used in Global/Regional Assimilation and Prediction System–Global Forecast System (CMA_GFS), and the performance improvements are confirmed relative to the previous FY‐3C/D MWHS‐II. Three batch experiments were implemented in CMA_GFS with four‐dimensional variational (4D‐Var) system—assimilating only the humidity‐sounding channels, the temperature‐sounding channels and the combined channels—to reveal the impact of assimilation by different channel groupings. Analysis results conclude that FY‐3E MWHS‐II radiances are beneficial to the humidity and temperature analysis fields. These results emphasize the advantage of simultaneously assimilating the humidity/temperature‐sounding channels, in which the former dominates the improvement above 700 hPa while the latter have a positive impact below 700 hPa. The forecast results also show that assimilating both the 183‐ and 118‐GHz channels further improves the forecast skills, especially short‐ to medium‐term forecasts in both hemispheres. FY‐3E MWHS‐II also improves the short‐term prediction of heavy rain, which is always weakly predicted in global forecast systems. This study shows that a three polar orbits system that FY‐3E began can produce marked effects in the numerical prediction system. This study also shines light on the application potential of the distinctive 118‐GHz channels of MWHS‐II.
first_indexed 2024-03-13T02:32:13Z
format Article
id doaj.art-6d173a2a31bc4ab69128da28b2981a5e
institution Directory Open Access Journal
issn 1350-4827
1469-8080
language English
last_indexed 2024-03-13T02:32:13Z
publishDate 2023-05-01
publisher Wiley
record_format Article
series Meteorological Applications
spelling doaj.art-6d173a2a31bc4ab69128da28b2981a5e2023-06-29T13:18:29ZengWileyMeteorological Applications1350-48271469-80802023-05-01303n/an/a10.1002/met.2133Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var systemHongyi Xiao0Wei Han1Peng Zhang2Yihong Bai3CMA Earth System Modeling and Prediction Centre (CEMC) Beijing ChinaCMA Earth System Modeling and Prediction Centre (CEMC) Beijing ChinaInnovation Center for FengYun Meteorological Satellite (FYSIC) Beijing ChinaInnovation Center for FengYun Meteorological Satellite (FYSIC) Beijing ChinaAbstract Radiance data from satellite microwave radiometers are becoming increasingly important in the assimilation of numerical prediction systems. FengYun‐3E (FY‐3E), which was launched in July 2021, as the first early morning orbital satellite among FY‐3 polar‐orbiting meteorological satellite series, can greatly enhance the atmospheric sounding capacity in three orbits compared with the two‐orbit system that is distributed in morning or afternoon orbit. Focusing on MicroWave Humidity Sounder‐2 (MWHS‐II) onboard it, the schemes for thinning, quality control, bias correction and observational error calculation are developed. The scan‐position‐dependent biases are assessed in each channel and increasing biases near the edges of scanline are found in several temperature‐sounding channels. The data quality is compared with four analogous instruments used in Global/Regional Assimilation and Prediction System–Global Forecast System (CMA_GFS), and the performance improvements are confirmed relative to the previous FY‐3C/D MWHS‐II. Three batch experiments were implemented in CMA_GFS with four‐dimensional variational (4D‐Var) system—assimilating only the humidity‐sounding channels, the temperature‐sounding channels and the combined channels—to reveal the impact of assimilation by different channel groupings. Analysis results conclude that FY‐3E MWHS‐II radiances are beneficial to the humidity and temperature analysis fields. These results emphasize the advantage of simultaneously assimilating the humidity/temperature‐sounding channels, in which the former dominates the improvement above 700 hPa while the latter have a positive impact below 700 hPa. The forecast results also show that assimilating both the 183‐ and 118‐GHz channels further improves the forecast skills, especially short‐ to medium‐term forecasts in both hemispheres. FY‐3E MWHS‐II also improves the short‐term prediction of heavy rain, which is always weakly predicted in global forecast systems. This study shows that a three polar orbits system that FY‐3E began can produce marked effects in the numerical prediction system. This study also shines light on the application potential of the distinctive 118‐GHz channels of MWHS‐II.https://doi.org/10.1002/met.21334D‐VarCMA_GFSFY‐3EMWHS‐IIsatellite data assimilation
spellingShingle Hongyi Xiao
Wei Han
Peng Zhang
Yihong Bai
Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system
Meteorological Applications
4D‐Var
CMA_GFS
FY‐3E
MWHS‐II
satellite data assimilation
title Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system
title_full Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system
title_fullStr Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system
title_full_unstemmed Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system
title_short Assimilation of data from the MWHS‐II onboard the first early morning satellite FY‐3E into the CMA global 4D‐Var system
title_sort assimilation of data from the mwhs ii onboard the first early morning satellite fy 3e into the cma global 4d var system
topic 4D‐Var
CMA_GFS
FY‐3E
MWHS‐II
satellite data assimilation
url https://doi.org/10.1002/met.2133
work_keys_str_mv AT hongyixiao assimilationofdatafromthemwhsiionboardthefirstearlymorningsatellitefy3eintothecmaglobal4dvarsystem
AT weihan assimilationofdatafromthemwhsiionboardthefirstearlymorningsatellitefy3eintothecmaglobal4dvarsystem
AT pengzhang assimilationofdatafromthemwhsiionboardthefirstearlymorningsatellitefy3eintothecmaglobal4dvarsystem
AT yihongbai assimilationofdatafromthemwhsiionboardthefirstearlymorningsatellitefy3eintothecmaglobal4dvarsystem