Articles | Volume 3, issue 1
https://doi.org/10.5194/ar-3-155-2025
https://doi.org/10.5194/ar-3-155-2025
Research article
 | 
28 Mar 2025
Research article |  | 28 Mar 2025

Unchanged PM2.5 levels over Europe during COVID-19 were buffered by ammonia

Nikolaos Evangeliou, Ondřej Tichý, Marit Svendby Otervik, Sabine Eckhardt, Yves Balkanski, and Didier A. Hauglustaine

Viewed

Total article views: 677 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
321 113 243 677 51 18 19
  • HTML: 321
  • PDF: 113
  • XML: 243
  • Total: 677
  • Supplement: 51
  • BibTeX: 18
  • EndNote: 19
Views and downloads (calculated since 02 Sep 2024)
Cumulative views and downloads (calculated since 02 Sep 2024)

Viewed (geographical distribution)

Total article views: 677 (including HTML, PDF, and XML) Thereof 677 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 01 Apr 2025
Download
Short summary
The COVID-19 lockdown measures in 2020 reduced emissions of various substances, improving air quality. However, PM2.5 stayed unchanged due to NH3 and related chemical transformations. Higher humidity favoured more SO42- production, as did the accumulated NH3. Excess NH3 reacted with HNO3 to make NO3-. In high-NH3 conditions such as those in 2020, a small reduction in NOx levels drove faster oxidation of NO3- and slower deposition of total inorganic NO3-, causing high secondary PM2.5.
Share
Altmetrics
Final-revised paper
Preprint