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Cited by 300

The DOI matches its Crossref record; 60 of the 60 references it cites were found in a registry or an index.

Global fine-scale changes in ambient NO2 during COVID-19 lockdowns

Open access
Cooper, Matthew J., Martin, Randall V., Hammer, Melanie S., Levelt, Pieternel F., Veefkind, Pepijn, Lamsal, Lok N., Krotkov, Nickolay A., Brook, Jeffrey R., McLinden, Chris A.·2022·Nature

Abstract

Nitrogen dioxide (NO 2) is an important contributor to air pollution and can adversely affect human health 1–9. A decrease in NO 2 concentrations has been reported as a result of lockdown measures to reduce the spread of COVID-19 10–20. Questions remain, however, regarding the relationship of satellite-derived atmospheric column NO 2 data with health-relevant ambient ground-level concentrations, and the representativeness of limited ground-based monitoring data for global assessment. Here we derive spatially resolved, global ground-level NO 2 concentrations from NO 2 column densities observed by the TROPOMI satellite instrument at sufficiently fine resolution (approximately one kilometre) to allow assessment of individual cities during COVID-19 lockdowns in 2020 compared to 2019. We apply these estimates to quantify NO 2 changes in more than 200 cities, including 65 cities without available ground monitoring, largely in lower-income regions. Mean country-level population-weighted NO 2 concentrations are 29% ± 3% lower in countries with strict lockdown conditions than in those without. Relative to long-term trends, NO 2 decreases during COVID-19 lockdowns exceed recent Ozone Monitoring Instrument (OMI)-derived year-to-year decreases from emission controls, comparable to 15 ± 4 years of reductions globally. Our case studies indicate that the sensitivity of NO 2 to lockdowns varies by country and emissions sector, demonstrating the critical need for spatially resolved observational information provided by these satellite-derived surface concentration estimates.

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Metadata

Authors
Cooper, M. J., Martin, R. V., Hammer, M. S., Levelt, P. F., Veefkind, P., Lamsal, L. N., Krotkov, N. A., Brook, J. R., & McLinden, C. A.
Venue
Nature
Published
2022-01-19
Volume
601
Issue
7893
Pages
380-387
ISSN
  • 0028-0836 (ISSN-L)
  • 1476-4687
OpenAlex
W4206210420
Cited by
300
References
60
FWCI
24.90
Type
journal article
Language
en
Open access
hybrid

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CoChat. (2026). Citation check: Global fine-scale changes in ambient NO2 during COVID-19 lockdowns. https://app.cochat.ai/papers/10.1038/s41586-021-04229-0
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Cooper, M. J., Martin, R. V., Hammer, M. S., Levelt, P. F., Veefkind, P., Lamsal, L. N., Krotkov, N. A., Brook, J. R., & McLinden, C. A. (2022). Global fine-scale changes in ambient NO2 during COVID-19 lockdowns. Nature. https://doi.org/10.1038/s41586-021-04229-0

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