Page 258 - 《高原气象》2025年第6期

高 原 气 象 44 卷
1666

Comparative and Quality Analysis of Radio Occultation Data

from FY-3E/GNOS and COSMIC-2

1， 2
1， 2
WANG Shihan ， YANG Shengpeng ， YIN Yan’an 1， 2
（1. Joint Center for Data Assimilation Research and Application， Nanjing University of Information Science
and Technology， Nanjing 210044， Jiangsu， China；
2. College of Atmospheric Science， Nanjing University of Information Science and Technology， Nanjing 210044， Jiangsu， China）

Abstract： Radio Occultation data are of great value in numerical weather forecasting and climate monitoring.
This study evaluates the deviation characteristics of occultation data from the FY-3E/GNOS and COSMIC-2 satel‐
lites with ERA5 reanalysis data. The results indicate that FY-3E/GNOS and COSMIC-2 exhibit high consistency
with ERA5 in the altitude range of 5 km to 30 km， with refractivity deviations less than 1% and bending angle
deviation is stable within ±0. 4%. However， in the lower atmosphere （below 5 km）， COSMIC-2 presents a max‐
imum negative bias of -1. 2% at altitudes below 4 km， while FY-3E/GNOS demonstrates a systematic positive bi‐
as below 5 km in the bending angle， and the refractivity shows negative deviations below 2 km in the low-lati‐
tude region and positive deviations from 2 to 4 km. Research findings indicate that the bending angle profiles of
FY-3E/GNOS are smoother than those of COSMIC-2， especially in the lower troposphere.
Key words： refractivity； GNSS Radio Occultation； quality analysis