First-time comparison between NO2 vertical columns from GEMS and Pandora measurements.

Autor: Serin Kim, Daewon Kim, Hyunkee Hong, Lim-Seok Chang, Hanlim Lee, Deok-Rae Kim, Donghee Kim, Jeong-Ah Yu, Dongwon Lee, Ukkyo Jeong, Chang-Kuen Song, Sang-Woo Kim, Sang Seo Park, Jhoon Kim, Hanisco, Thomas F., Junsung Park, Wonei Choi, Kwangyul Lee
Předmět:
Zdroj: Atmospheric Measurement Techniques Discussions; 3/8/2023, p1-22, 22p
Abstrakt: The Geostationary Environmental Monitoring Spectrometer (GEMS) is a UV-visible spectrometer onboard the GEO-KOMPSAT-2B satellite launched into geostationary orbit in February 2020. To evaluate GEMS NO2 column data, comparison was carried out using NO2 vertical column density (VCD) measured using direct-sunlight observations by the Pandora spectrometer system at four sites in Seosan, South Korea, during November 2020 to January 2021. Correlation coefficients between GEMS and Pandora NO2 data at four sites ranged from 0.35 to 0.48, with root mean square errors (RMSEs) from 4.7 × 1015 molec. cm-2 to 5.5 × 1015 molec. cm-2 for cloud fraction (CF) < 0.7. Higher correlation coefficients of 0.62-0.78 with lower RMSEs from 3.3 × 1015 molec. cm-2 to 4.3 × 1015 molec. cm-2 were found with CF < 0.3, indicating the higher sensitivity of GEMS to atmospheric NO2 in less-cloudy conditions. Overall, GEMS NO2 column data tend to be lower than those of Pandora due to differences in representative spatial coverage, with a large negative bias under high-CF conditions. With correction for horizontal representativeness in Pandora measurement coverage, the correlation coefficients range from 0.69 to 0.81 with RMSEs from 3.2 × 1015 molec. cm-2 to 4.9 × 1015 molec. cm-2 were achieved for CF < 0.3, showing the better correlation with the correction than that without the correction. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index