- 1University of Suwon, Hwaseong-si, Gyeonggi-do, South Korea (hakwon@suwon.ac.kr)
- 2National Institute of Environmental Research (NIER), Incheon, South Korea
- 3University of California, Los Angeles, CA, USA
- 4National Center for Atmospheric Research (NCAR), Boulder, CO, USA
- 5NASA Goddard Space Flight Center, Greenbelt, MD, USA
- 6Yonsei University, Seoul, South Korea
- 7Pukyong National University, Busan, South Korea
The Airborne and Satellite Investigation of Asian Air Quality (ASIA-AQ) campaign was conducted from February to March 2024 to investigate air quality in Asia. One of the primary scientific objectives of the ASIA-AQ campaign was satellite validation and interpretation, especially for the Geostationary Environment Monitoring Spectrometer (GEMS) products. To achieve this goal, nitrogen dioxide (NO2), formaldehyde (HCHO), aerosols, and other trace gases were measured using airborne and ground-based instruments. Here, we present trace gas and aerosol profile measurements from the ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) SkySpec instruments in South Korea during ASIA-AQ. We use the RAPSODI (Retrieval of Atmospheric Parameters from Spectroscopic Observations using DOAS Instruments) algorithm to retrieve profiles from MAX-DOAS measurements. The NO2 surface concentrations retrieved from MAX-DOAS are in good agreement with in-situ measurements, showing correlation coefficients of 0.63 (north direction) and 0.88 (south direction), but with negative biases of –48% and –15%, respectively. In comparison with airborne in-situ measurements, MAX-DOAS NO2 concentrations below 1 km are lower than those measured by in-situ instruments (NASA GSFC CANOE and NCAR NOx and O3 Chemiluminescence) onboard NASA’s DC-8 aircraft. These negative biases in comparison with surface and aircraft measurements are influenced by the heterogeneity of NO2 concentrations due to the differing locations of MAX-DOAS and in-situ instruments. Aerosol optical depths (AODs) derived from MAX-DOAS are well correlated with those from the Aerosol Robotic Network (AERONET). Using these MAX-DOAS measurements, we validate GEMS NO2 and AOD products. GEMS NO2 version 3 products reduce positive biases occurring in the version 2 products but remain lower than those from MAX-DOAS NO2 products. GEMS AOD products are in good agreement with AERONET and MAX-DOAS products.
How to cite: Kwon, H.-A., Ahn, S., Tirpitz, J.-L., Franchin, A., St Clair, J., Gupta, P., Lind, E., Kim, J., and Jeong, U.: Trace gas and aerosol profile measurements from MAX-DOAS in South Korea during ASIA-AQ, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-4660, https://doi.org/10.5194/egusphere-egu25-4660, 2025.
