Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway
Abstract During the first half of 2020, the Italian government imposed several restrictions to limit the spread of the COVID‐19 pandemic: at the beginning of March, a heavy lockdown regime was introduced leading to a drastic reduction of traffic and, consequently, traffic‐related emissions. The aim...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2023-03-01
|
| Series: | Meteorological Applications |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/met.2123 |
| _version_ | 1797838591409258496 |
|---|---|
| author | Elena Bertazza Andrea Bisignano Marco Falocchi Lorenzo Giovannini |
| author_facet | Elena Bertazza Andrea Bisignano Marco Falocchi Lorenzo Giovannini |
| author_sort | Elena Bertazza |
| collection | DOAJ |
| description | Abstract During the first half of 2020, the Italian government imposed several restrictions to limit the spread of the COVID‐19 pandemic: at the beginning of March, a heavy lockdown regime was introduced leading to a drastic reduction of traffic and, consequently, traffic‐related emissions. The aim of this study is to evaluate the effects of these restrictions on pollutant concentrations close to a stretch of the Italian A22 motorway lying in the Alpine Adige valley. In particular, the analysis focuses on measured concentrations of nitrogen dioxide (NO2) and black carbon (BC). Results show that, close to the motorway, NO2 concentrations dropped by around 45% during the lockdown period with respect to the same time period of the previous 3 years. The equivalent analysis for BC shows that the component related to biomass burning, mostly due to domestic heating, was not particularly affected by the restrictions, while the BC component related to fossil fuels, directly connected to traffic, plummeted by almost 60% with respect to the previous years. Since atmospheric concentrations of pollutants depend both on emissions and meteorological conditions, which can mask the variations in the emission regime, a random forest algorithm is also applied to the measured concentrations, in order to better evaluate the effects of the restrictions on emissions. This procedure allows for obtaining business‐as‐usual and meteorologically normalized time series of both NO2 and BC concentrations. The results derived from the random forest algorithm clearly confirm the drop in NO2 emissions at the beginning of the lockdown period, followed by a slow and partial recovery in the following months. They also confirm that, during the lockdown, emissions of the BC component due to biomass burning were not significantly affected, while those of the BC component related to fossil fuels underwent an abrupt drop. |
| first_indexed | 2024-04-09T15:43:19Z |
| format | Article |
| id | doaj.art-a0c9f9dfa5b54c028cc4d9aadc88f1c8 |
| institution | Directory Open Access Journal |
| issn | 1350-4827 1469-8080 |
| language | English |
| last_indexed | 2024-04-09T15:43:19Z |
| publishDate | 2023-03-01 |
| publisher | Wiley |
| record_format | Article |
| series | Meteorological Applications |
| spelling | doaj.art-a0c9f9dfa5b54c028cc4d9aadc88f1c82023-04-27T05:50:37ZengWileyMeteorological Applications1350-48271469-80802023-03-01302n/an/a10.1002/met.2123Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorwayElena Bertazza0Andrea Bisignano1Marco Falocchi2Lorenzo Giovannini3Department of Civil, Environmental and Mechanical Engineering University of Trento Trento ItalyDepartment of Civil, Environmental and Mechanical Engineering University of Trento Trento ItalyCISMA s.r.l., Centro di Ingegneria e Sviluppo Modelli per l'Ambiente Bolzano ItalyDepartment of Civil, Environmental and Mechanical Engineering University of Trento Trento ItalyAbstract During the first half of 2020, the Italian government imposed several restrictions to limit the spread of the COVID‐19 pandemic: at the beginning of March, a heavy lockdown regime was introduced leading to a drastic reduction of traffic and, consequently, traffic‐related emissions. The aim of this study is to evaluate the effects of these restrictions on pollutant concentrations close to a stretch of the Italian A22 motorway lying in the Alpine Adige valley. In particular, the analysis focuses on measured concentrations of nitrogen dioxide (NO2) and black carbon (BC). Results show that, close to the motorway, NO2 concentrations dropped by around 45% during the lockdown period with respect to the same time period of the previous 3 years. The equivalent analysis for BC shows that the component related to biomass burning, mostly due to domestic heating, was not particularly affected by the restrictions, while the BC component related to fossil fuels, directly connected to traffic, plummeted by almost 60% with respect to the previous years. Since atmospheric concentrations of pollutants depend both on emissions and meteorological conditions, which can mask the variations in the emission regime, a random forest algorithm is also applied to the measured concentrations, in order to better evaluate the effects of the restrictions on emissions. This procedure allows for obtaining business‐as‐usual and meteorologically normalized time series of both NO2 and BC concentrations. The results derived from the random forest algorithm clearly confirm the drop in NO2 emissions at the beginning of the lockdown period, followed by a slow and partial recovery in the following months. They also confirm that, during the lockdown, emissions of the BC component due to biomass burning were not significantly affected, while those of the BC component related to fossil fuels underwent an abrupt drop.https://doi.org/10.1002/met.2123black carbonCOVID‐19meteorological normalizationnitrogen dioxiderandom foresttraffic‐related pollution |
| spellingShingle | Elena Bertazza Andrea Bisignano Marco Falocchi Lorenzo Giovannini Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway Meteorological Applications black carbon COVID‐19 meteorological normalization nitrogen dioxide random forest traffic‐related pollution |
| title | Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway |
| title_full | Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway |
| title_fullStr | Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway |
| title_full_unstemmed | Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway |
| title_short | Effects of COVID‐19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major Italian motorway |
| title_sort | effects of covid 19 lockdown measures on nitrogen dioxide and black carbon concentrations close to a major italian motorway |
| topic | black carbon COVID‐19 meteorological normalization nitrogen dioxide random forest traffic‐related pollution |
| url | https://doi.org/10.1002/met.2123 |
| work_keys_str_mv | AT elenabertazza effectsofcovid19lockdownmeasuresonnitrogendioxideandblackcarbonconcentrationsclosetoamajoritalianmotorway AT andreabisignano effectsofcovid19lockdownmeasuresonnitrogendioxideandblackcarbonconcentrationsclosetoamajoritalianmotorway AT marcofalocchi effectsofcovid19lockdownmeasuresonnitrogendioxideandblackcarbonconcentrationsclosetoamajoritalianmotorway AT lorenzogiovannini effectsofcovid19lockdownmeasuresonnitrogendioxideandblackcarbonconcentrationsclosetoamajoritalianmotorway |