دورية أكاديمية

Impacts of the COVID-19 lockdown on air pollution at regional and urban background sites in northern Italy

التفاصيل البيبلوغرافية
العنوان: Impacts of the COVID-19 lockdown on air pollution at regional and urban background sites in northern Italy
المؤلفون: J.-P. Putaud, L. Pozzoli, E. Pisoni, S. Martins Dos Santos, F. Lagler, G. Lanzani, U. Dal Santo, A. Colette
المصدر: Atmospheric Chemistry and Physics, Vol 21, Pp 7597-7609 (2021)
بيانات النشر: Copernicus Publications, 2021.
سنة النشر: 2021
المجموعة: LCC:Physics
LCC:Chemistry
مصطلحات موضوعية: Physics, QC1-999, Chemistry, QD1-999
الوصف: The COVID-19 lockdown measures gradually implemented in Lombardy (northern Italy) from 23 February 2020 led to a downturn in several economic sectors with possible impacts on air quality. Several communications claimed in the first weeks of March 2020 that the mitigation in air pollution observed at that time was actually related to these lockdown measures without considering that seasonal variations in emissions and meteorology also influence air quality. To determine the specific impact of lockdown measures on air quality in northern Italy, we compared observations from the European Commission Atmospheric Observatory of Ispra (regional background) and from the regional environmental protection agency (ARPA) air monitoring stations in the Milan conurbation (urban background) with expected values for these observations using two different approaches. On the one hand, intensive aerosol variables determined from specific aerosol characterisation observations performed in Ispra were compared to their 3-year averages. On the other hand, ground-level measured concentrations of atmospheric pollutants (NO2, PM10, O3, NO, SO2) were compared to expected concentrations derived from the Copernicus Atmosphere Monitoring Service Regional (CAMS) ensemble model forecasts, which did not account for lockdown measures. From these comparisons, we show that NO2 concentrations decreased as a consequence of the lockdown by −30 % and −40 % on average at the urban and regional background sites, respectively. Unlike NO2, PM10 concentrations were not significantly affected by lockdown measures. This could be due to any decreases in PM10 (and PM10 precursors) emissions from traffic being compensated for by increases in emissions from domestic heating and/or from changes in the secondary aerosol formation regime resulting from the lockdown measures. The implementation of the lockdown measures also led to an increase in the highest O3 concentrations at both the urban and regional background sites resulting from reduced titration of O3 by NO. The relaxation of the lockdown measures beginning in May resulted in close-to-expected NO2 concentrations in the urban background and to significant increases in PM10 in comparison to expected concentrations at both regional and urban background sites.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1680-7316
1680-7324
Relation: https://acp.copernicus.org/articles/21/7597/2021/acp-21-7597-2021.pdf; https://doaj.org/toc/1680-7316; https://doaj.org/toc/1680-7324
DOI: 10.5194/acp-21-7597-2021
URL الوصول: https://doaj.org/article/84ba568b9c22460daff96ab225d49814
رقم الأكسشن: edsdoj.84ba568b9c22460daff96ab225d49814
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:16807316
16807324
DOI:10.5194/acp-21-7597-2021