Assessing Spatiotemporal Variability in NO2 and O3 Along the Korean Peninsula Using Remote Sensing and Ground-Based Observations

The transport and atmospheric dynamics of air pollutants play a vital role in human and environmental health. Of particular concern to us are nitrogen dioxide (NO2) emissions in urbanized and coastal areas, as well as tropospheric ozone (O3). Elevated levels of tropospheric NO2 and O3 pose can impact human health, local and regional biogeochemical balance and ecosystem fitness. Our research focuses on the use of ground-based and satellite products to study the spatial and temporal variability of NO2 and O3 in urban and coastal South Korea. Data sets are derived from remotely sensed direct-sun irradiance measurements of TCNO2 and TCO3 using Pandora spectrometers located at 8 ground sites and 1 boat-mounted sensor, as well as satellite observations from the Ozone Monitoring Instrument (OMI) on the Aura satellite. The study focuses on the dates of the KORUS-AQ/KORUS-OC campaigns, which took place between May 18, 2016 through June 2, 2016, and provided coastal and off-shore measurements of atmospheric composition and coastal ocean biogeochemistry. The Pandora instrument offers continuous coverage of the local area, providing a detailed understanding of NO2 and O3 temporal variability. Ground-based stations allowed monitoring of small-scale diurnal variability in urban and near-urban environments, while the ship-board Pandora deployed on the Onnuri research vessel provided valuable data on off-shore behavior of trace gases. Collected data was subjected to statistical and GIS (Geographic Information System) analysis, quantifying and mapping, respectively, the spatial and temporal variability of total column amounts of NO2 and O3 along the Korean Peninsula. Results are shown for the eight sites where different Pandora instruments are used. There is a notable difference in TCNO2 variability which correlates with population and land use.