Urban Aerosol Properties Measured in Southeast Asian During the 2024 NASA ASIA-AQ Flight Campaign

SAYANTEE ROY, Francesca Gallo, Carolyn Jordan, Edward Winstead, Elizabeth Wiggins, Michael Shook, Raphael Maerkl, Guy Symonds, Dongwook Kim, Seonsik Yun, Douglas A. Day, Pedro Campuzano-Jost, Jose-Luis Jimenez, Luke Ziemba, Richard Moore, NASA Langley Research Center

     Abstract Number: 340
     Working Group: Urban Aerosols

Abstract
NASA conducted the Airborne and Satellite Investigation of Asian Air Quality (ASIA-AQ) flight campaign in early 2024, leveraging a multi-perspective approach that integrates aircraft, satellite, and ground-based data. It covered four countries, Philippines, South Korea, Thailand, and Taiwan. The NASA DC-8 aircraft was deployed to make in-situ measurements of a wide suite of gas and particle parameters close to the pollution emissions in these locations. Our group, the Langley Aerosol Research Group (LARGE), provided real-time measurements of aerosol microphysical and optical properties, and meteorological parameters. In this work, we focus on a comparative analysis of aerosol microphysical and optical properties over three different megacities – Manila, Seoul and Bangkok. These cities represent diverse environmental conditions, influenced by different emission sources, boundary layer dynamics, and topography. Particle number size distributions and optical properties were examined to identify the contributions of scattering and absorbing aerosols and to infer dominant source types. By analyzing vertical and horizontal profiles of aerosols alongside meteorological data, we assess the influence of local processes and regional transport on urban air quality. Key discussions will underscore substantial spatial variability in aerosols properties, contribution of absorbing and scattering aerosols, role of boundary layer dynamics, and evidence of regional pollution transport within the ASIA-AQ domain.