Impact of the COVID-19 “Lockdown” on Air Quality in Athens
(2025) In Master Thesis in Geographical Information Science GISM01 20252Dept of Physical Geography and Ecosystem Science
- Abstract
- This thesis examined the impact of the COVID-19 lockdown on Athenian air quality from March 23rd to May 5th, 2020. The Attica Ground Measuring Network was used to measure the concentrations of NO, NO₂, SO₂, CO, PM₁₀, PM₂.₅, and O₃ for the 2020 lockdown and for the same time period from 2005 to 2019 as reference.
Nitric oxide (NO) and nitrogen dioxide (NO₂) concentrations decreased by up to 75% and 49%, respectively, compared to the reference period, with the exception of the ELE station, where NO levels increased by 17%, due to continued industrial and logistics activity. Ozone (O₃) levels varied across monitoring stations, mostly increasing in localities where NOx decreased, an outcome that aligns with the NOx-O₃ photochemical behavior... (More) - This thesis examined the impact of the COVID-19 lockdown on Athenian air quality from March 23rd to May 5th, 2020. The Attica Ground Measuring Network was used to measure the concentrations of NO, NO₂, SO₂, CO, PM₁₀, PM₂.₅, and O₃ for the 2020 lockdown and for the same time period from 2005 to 2019 as reference.
Nitric oxide (NO) and nitrogen dioxide (NO₂) concentrations decreased by up to 75% and 49%, respectively, compared to the reference period, with the exception of the ELE station, where NO levels increased by 17%, due to continued industrial and logistics activity. Ozone (O₃) levels varied across monitoring stations, mostly increasing in localities where NOx decreased, an outcome that aligns with the NOx-O₃ photochemical behavior in VOC-limited conditions. Sulfur dioxide (SO₂) declined by up to 72%, PM₁₀, PM₂.₅ decreased by up to 45% and carbon monoxide (CO) also showed reductions by up to 78%, particularly at sites with high traffic burden.
These findings highlight the positive effect that restrictive measures in transportation and industry had on the Athenian air quality and align with similar findings from Greece and from around the world. While meteorological conditions did not show any notable anomalies during the study period, compared to the reference period, the lack of their direct integration into the analysis, along with the unaccounted influence of the prior economic crisis, represent limitations of this research. Valuable information is provided in this thesis for policy makers by showing that reducing traffic and industrial emissions, with targeted policies, can improve air quality in densely built cities and cities with poor public transport system and traffic congestion, such as Athens. (Less) - Popular Abstract
- In spring 2020, the Greek authorities as a preliminary measure against the increasing COVID-19 cases imposed a strict lockdown across the entire country, including the capital, Athens. This lockdown transformed the vibrant city of Athens into a scene from a dystopian film: empty roads, closed shops, silent schoolyards. This unexpected and grave situation offered a rare opportunity to investigate how the sudden reduction of human activity, especially in transportation and industry, would affect the city’s air quality.
This study compared air pollution levels during the lockdown (March 23 to May 5, 2020) with the same period (March 23 to May 5) from 2005 to 2019. Data from the Attica Ground Measuring Network were used in order to examine... (More) - In spring 2020, the Greek authorities as a preliminary measure against the increasing COVID-19 cases imposed a strict lockdown across the entire country, including the capital, Athens. This lockdown transformed the vibrant city of Athens into a scene from a dystopian film: empty roads, closed shops, silent schoolyards. This unexpected and grave situation offered a rare opportunity to investigate how the sudden reduction of human activity, especially in transportation and industry, would affect the city’s air quality.
This study compared air pollution levels during the lockdown (March 23 to May 5, 2020) with the same period (March 23 to May 5) from 2005 to 2019. Data from the Attica Ground Measuring Network were used in order to examine several pollutants (NO, NO₂, SO₂, CO, PM₁₀, PM₂.₅, and O₃) commonly linked to traffic and industry.
The measurements showed that the air quality in Athens improved significantly during the lockdown. Pollutant concentrations dropped sharply across the city, except in the few places where industrial work continued, with the results showing smaller pollutant reductions. Ozone behaved differently and increased in several areas. This ozone behavior is an indication that air pollution is a complex system where changes in one pollutant can influence another and that an effective mitigation strategy involves a variety of measures.
These results showed that reductions in vehicular and industrial emissions can lead to a rapid and significant improvement of air quality in cities like Athens. These findings were similar to observations made during strict lockdowns in other cities of Greece and around the world. The analysis did not incorporate meteorological influences or the effects of the recent economic crisis on transportation patterns.
The Athenian 2020 lockdown period provided valuable insight into how quickly the air can improve when major pollution sources are reduced, it provides useful indications of how targeted reductions in traffic and industrial emissions could benefit cities, especially the ones that are burdened by heavy congestion and dense urban structure. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9215983
- author
- Gerafentis, Spyridon LU
- supervisor
- organization
- course
- GISM01 20252
- year
- 2025
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Geography, GIS, COVID-19, lockdown, Athens, pollution, nitric oxide, nitrogen dioxide, sulfur dioxide, ozone, particulate matter, carbon monoxide
- publication/series
- Master Thesis in Geographical Information Science
- report number
- 201
- language
- English
- id
- 9215983
- date added to LUP
- 2025-12-04 17:15:18
- date last changed
- 2025-12-04 17:15:18
@misc{9215983,
abstract = {{This thesis examined the impact of the COVID-19 lockdown on Athenian air quality from March 23rd to May 5th, 2020. The Attica Ground Measuring Network was used to measure the concentrations of NO, NO₂, SO₂, CO, PM₁₀, PM₂.₅, and O₃ for the 2020 lockdown and for the same time period from 2005 to 2019 as reference.
Nitric oxide (NO) and nitrogen dioxide (NO₂) concentrations decreased by up to 75% and 49%, respectively, compared to the reference period, with the exception of the ELE station, where NO levels increased by 17%, due to continued industrial and logistics activity. Ozone (O₃) levels varied across monitoring stations, mostly increasing in localities where NOx decreased, an outcome that aligns with the NOx-O₃ photochemical behavior in VOC-limited conditions. Sulfur dioxide (SO₂) declined by up to 72%, PM₁₀, PM₂.₅ decreased by up to 45% and carbon monoxide (CO) also showed reductions by up to 78%, particularly at sites with high traffic burden.
These findings highlight the positive effect that restrictive measures in transportation and industry had on the Athenian air quality and align with similar findings from Greece and from around the world. While meteorological conditions did not show any notable anomalies during the study period, compared to the reference period, the lack of their direct integration into the analysis, along with the unaccounted influence of the prior economic crisis, represent limitations of this research. Valuable information is provided in this thesis for policy makers by showing that reducing traffic and industrial emissions, with targeted policies, can improve air quality in densely built cities and cities with poor public transport system and traffic congestion, such as Athens.}},
author = {{Gerafentis, Spyridon}},
language = {{eng}},
note = {{Student Paper}},
series = {{Master Thesis in Geographical Information Science}},
title = {{Impact of the COVID-19 “Lockdown” on Air Quality in Athens}},
year = {{2025}},
}