[A-AS11] Atmospheric Chemistry

[AAS11-03] Validation of NO₂ vertical profile from remote sensing and estimation of emission rates using airborne measurements

*Yongjoo Choi¹, Yugo Kanaya², Jongbyeok Jun¹, Giyeol Lee¹, Beom-Keun Seo³, Lim-Seok Chang⁴ (1.Hankuk University of Foreign Studies, 2.Japan Agency for Marine-Earth Science and Technology , 3.Hanseo University, 4.National Institute of Environmental Research)

Keywords:airborne measurement, MAX-DOAS, NO2 vertical profile, emission rates

During the Airborne and Satellite Investigation of Asian Air Quality (ASIA-AQ) campaign, we conducted airborne measurements using a C90GT aircraft for two distinct research purposes: (1) estimation of emission rates of NO₂ from emission sources and (2) validation of NO₂ vertical distribution based on ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations and Geostationary Environment Monitoring Spectrometer (GEMS) satellite data. For emission rate estimation, research flights were conducted over cattle sheds (using zigzag flight patterns) located on the west coast and in the central part of the Korean Peninsula, respectively. The measured NO₂ concentrations were used to estimate emission rates by applying our ensemble model, which combines mass balance and Gaussian footprint methods. For validation of the NO₂ vertical distribution, the spiral flights (varying the flight altitude up to 3 km) were conducted three times a day (morning, noon, and afternoon) to capture the temporal evolution of the NO₂ layer. These results will help validate bottom-up emission inventories and improve the accuracy of NO₂ tropospheric vertical column density estimates from GEMS by updating NO₂ vertical profiles to better reflect real-world conditions.