Abstract
We analyzed annual and seasonal frequency in aerosol type over an 8-year period (2012–2019) to identify aerosol parameter trends over four ground sites and country regions in Korea, China, and Japan by using the Aerosol Robotic Network (AERONET), and the satellite-based Visible Infrared Imaging Radiometer Suite (VIIRS) and Ozone Monitoring Instrument (OMI). Decreasing trends are shown for aerosol optical depth (AOD), Ångström exponent (AE), and fine mode fraction (FMF) in all countries. The decreasing trend in these data is considered to be due to a decrease in anthropogenic emissions. For the aerosol type frequency, decreases in the proportions of carbonaceous aerosols (CA) and non-absorbing aerosols (NA) were shown in the ground and satellite data, respectively. At most sites, the fractions of low AOD case (LOW) increased, whereas those of the Black and Brown Carbon (BC + BrC) category decreased. In Seoul, the fraction of LOW increased from 48.9% to 70.0%, and that of BC + BrC decreased continuously from 20.4% to 11.1% during 2012–2019. Beijing, on the other hand, showed decreasing LOW from 83.3% (2012) to 52.0% (2019), and that of BC + BrC increased significantly, from 2.4% to 26.2%. The satellite data showed that the percentage of LOW increased continuously, while that of NA aerosols decreased continuously in East Asia. A noticeable decrease in the fraction of CA was detected in China [21.5% (2013) to 11.2% (2019)]. In all countries, CA and NA aerosols had the greatest effect in winter and summer, respectively. We also detected significant differences between the fractions of NA and BC between the ground and satellite data. Changes in aerosol type and properties were observed concurrently in all ground and satellite data, and changes in aerosol type may explain the increasing and decreasing trends that we recorded for most parameters. Consistent results from both ground and satellite data suggest a steady decreasing in fine aerosol pollution in East Asia.
Original language | English |
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Article number | 106457 |
Journal | Atmospheric Research |
Volume | 280 |
DOIs | |
Publication status | Published - 2022 Dec 15 |
Bibliographical note
Funding Information:This work has supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (NRF-2020R1C1C1013628) and supported by the research fund of UNIST (Ulsan National Institute of Science & Technology) (No. 1.190139.01). We acknowledge the NASA Earth Science Division, S-NPP/VIIRS and Aura/OMI science team for the high-quality products. The authors thank all the researchers and staff for establishing and maintaining the AERONET sites used in this study.
Funding Information:
This work has supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) ( NRF-2020R1C1C1013628 ) and supported by the research fund of UNIST (Ulsan National Institute of Science & Technology) (No. 1.190139.01 ). We acknowledge the NASA Earth Science Division, S-NPP/VIIRS and Aura/OMI science team for the high-quality products. The authors thank all the researchers and staff for establishing and maintaining the AERONET sites used in this study.
Publisher Copyright:
© 2022 The Author(s)
All Science Journal Classification (ASJC) codes
- Atmospheric Science