Increased number concentrations of small particles explain perceived stagnation in air quality over Korea
<p>The atmospheric visibility in South Korea has not improved despite decreasing mass concentrations of particulate matter (PM<span class="inline-formula">)<sub>2.5</sub></span>. Since visibility is influenced by particle size and composition as well as meteor...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2025-01-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/25/1023/2025/acp-25-1023-2025.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | <p>The atmospheric visibility in South Korea has not improved despite decreasing mass concentrations of particulate matter (PM<span class="inline-formula">)<sub>2.5</sub></span>. Since visibility is influenced by particle size and composition as well as meteorological factors, light detection and ranging (lidar) data provided by the National Institute for Environmental Studies in Japan and PM<span class="inline-formula"><sub>2.5</sub></span> measurements retrieved from AirKorea are used to determine the trends in PM<span class="inline-formula"><sub>2.5</sub></span> mass extinction efficiency (MEE) in Seoul and Ulsan, South Korea, from 2015 to 2020. Moreover, the monthly trends in the Ångström exponent and relative and absolute humidity are determined to identify the factors influencing PM<span class="inline-formula"><sub>2.5</sub></span> MEE. The monthly average PM<span class="inline-formula"><sub>2.5</sub></span> MEE exhibits an increasing trend in Seoul (<span class="inline-formula">+</span>0.04 m<span class="inline-formula"><sup>2</sup></span> g<span class="inline-formula"><sup>−1</sup></span> per month) and Ulsan (<span class="inline-formula">+</span>0.07 m<span class="inline-formula"><sup>2</sup></span> g<span class="inline-formula"><sup>−1</sup></span> per month). Relative humidity increases by <span class="inline-formula">+</span>0.070 % and <span class="inline-formula">+</span>0.095 % per month in Seoul and Ulsan, respectively, and absolute humidity increases by <span class="inline-formula">+</span>0.029 and <span class="inline-formula">+</span>0.010 g m<span class="inline-formula"><sup>−3</sup></span> per month, respectively. However, the trends in these variables are not statistically significant. The Ångström exponent increases by <span class="inline-formula">+</span>0.005 and <span class="inline-formula">+</span>0.011 per month in Seoul and Ulsan, respectively, indicating that the MEE increases as the size of the particles becomes smaller each year. However, due to limitations when obtaining long-term composition data in this study, further research is needed to accurately determine the causes of the increase in PM<span class="inline-formula"><sub>2.5</sub></span> MEE. Such an increase in PM<span class="inline-formula"><sub>2.5</sub></span> MEE may have limited the improvements in visibility and adversely affected public perception of air quality improvement even though the PM<span class="inline-formula"><sub>2.5</sub></span> mass concentration in South Korea is continuously decreasing.</p> |
|---|---|
| ISSN: | 1680-7316 1680-7324 |