A seasonal analysis of aerosol NO 3 − sources and NO x oxidation pathways in the Southern Ocean marine boundary layer
Nitrogen oxides, collectively referred to as NO x (NO + NO 2 ), are an important component of atmospheric chemistry involved in the production and destruction of various oxidants that contribute to the oxidative capacity of the troposphere. The primary sink for NO x is atmospheric nitrate, which has...
| Published in: | Atmospheric Chemistry and Physics |
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| Main Authors: | , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Copernicus Publications
2023
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| Subjects: | |
| Online Access: | https://doi.org/10.5194/acp-23-5605-2023 https://doaj.org/article/ba9767e5b43d4ea3a635dd2764d08f26 |
| Summary: | Nitrogen oxides, collectively referred to as NO x (NO + NO 2 ), are an important component of atmospheric chemistry involved in the production and destruction of various oxidants that contribute to the oxidative capacity of the troposphere. The primary sink for NO x is atmospheric nitrate, which has an influence on climate and the biogeochemical cycling of reactive nitrogen. NO x sources and NO x -to-NO 3 - <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="78ed0f7e81615226176402cdd6a1afd5"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-23-5605-2023-ie00003.svg" width="9pt" height="16pt" src="acp-23-5605-2023-ie00003.png"/></svg:svg> formation pathways remain poorly constrained in the remote marine boundary layer of the Southern Ocean, particularly outside of the more frequently sampled summer months. This study presents seasonally resolved measurements of the isotopic composition ( δ 15 N, δ 18 O, and Δ 17 O) of atmospheric nitrate in coarse-mode ( > 1 µ m) aerosols, collected between South Africa and the sea ice edge in summer, winter, and spring. Similar latitudinal trends in δ 15 N–NO 3 - <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="5a2143864edd3f7cf8f1639018917994"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-23-5605-2023-ie00004.svg" width="9pt" height="16pt" src="acp-23-5605-2023-ie00004.png"/></svg:svg> were observed in summer and spring, suggesting similar NO x sources. Based on δ 15 N–NO 3 - <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="9pt" height="16pt" class="svg-formula" dspmath="mathimg" md5hash="9a17d6ab4c67d7f6701d29ccd0703b2e"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-23-5605-2023-ie00005.svg" width="9pt" height="16pt" src="acp-23-5605-2023-ie00005.png"/></svg:svg> , the main NO x sources were likely a ... |
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