Preview of the future application of the environmental geo-satellites data using aircraft platform: Estimation of anthropogenic VOC emissions from formaldehyde columns

The Geostationary Environment Monitoring Spectrometer (GEMS) will be launched in February 2020 and will provide hourly observations of atmospheric compositions in the daytime. Prior to the GEMS launch, we explore an application of GEMS data as constraints for estimating anthropogenic volatile organic compound (AVOC) emissions in South Korea using formaldehyde (HCHO) vertical column densities observations from the Geostationary Trace gas and Aerosol Sensor Optimization (GeoTASO) onboard the B200 aircraft during the KORUS-AQ campaign. Our top-down estimates of total AVOC emissions are higher by a factor of four over the petrochemical industries compared to the bottom-up emissions. However, the national AVOC emissions from the top-down estimates are by 37% lower than those of the bottom-up emission inventory in South Korea. We also show that hourly column observations of HCHO can improve not only the total magnitude of AVOC emissions but also their diurnal variation, which is poorly constrained and used in air quality models. Our hourly estimates of AVOC emissions may, thus, improve air quality model simulations in which the simulated ozone sensitivity to AVOC emission changes are also investigated.