Southern Hemisphere mid- and high-latitudinal AOD, CO, NO2, and HCHO: spatiotemporal patterns revealed by satellite observations

• Published in: Progress in Earth and Planetary Science
• Main Authors: Ahn, Dha Hyun, Choi, Taejin, Kim, Jhoon, Park, Sang Seo, Lee, Yun Gon, Kim, Seong-Joong, Koo, Ja-Ho
• Other Authors: 안다현, 최태진, 김준, 박상서, 이윤곤, 김성중, 구자호
• Format: Article in Journal/Newspaper
• Language: English
• Published: BioMed Central 2019
• Subjects: Climatology; Aerosol optical depth; Carbon monoxide; Nitrogen dioxide; Formaldehyde; Southern Hemisphere; Antarctic; Antarc*; Antarctica; Korea Polar Research Institute
• Online Access: https://hdl.handle.net/10371/153148; https://doi.org/10.1186/s40645-019-0277-y

To assess air pollution emitted in Southern Hemisphere mid-latitudes and transported to Antarctica, we investigate the climatological mean and temporal trends in aerosol optical depth (AOD), carbon monoxide (CO), nitrogen dioxide (NO2), and formaldehyde (HCHO) columns using satellite observations. Generally, all these measurements exhibit sharp peaks over and near the three nearby inhabited continents: South America, Africa, and Australia. This pattern indicates the large emission effect of anthropogenic activities and biomass burning processes. High AOD is also found over the Southern Atlantic Ocean, probably because of the sea salt production driven by strong winds. Since the pristine Antarctic atmosphere can be polluted by transport of air pollutants from the mid-latitudes, we analyze the 10-day back trajectories that arrive at Antarctic ground stations in consideration of the spatial distribution of mid-latitudinal AOD, CO, NO2, and HCHO. We find that the influence of mid-latitudinal emission differs across Antarctic regions: western Antarctic regions show relatively more back trajectories from the mid-latitudes, while the eastern Antarctic regions do not show large intrusions of mid-latitudinal air masses. Finally, we estimate the long-term trends in AOD, CO, NO2, and HCHO during the past decade (2005–2016). While CO shows a significant negative trend, the others show overall positive trends. Seasonal and regional differences in trends are also discussed. This work was supported by the Korea Polar Research Institute (KOPRI, PE18010). Additionally, this work was supported by grant (NRF2018R1C1B6008223) from the National Research Foundation of Korea (NRF), funded by the Korean government.