Effects of COVID-Induced Mobility Restrictions and Weather Conditions on Air Quality in Hungary

Abstract

Similarly to other countries, the first wave of the COVID pandemic induced a collapse of mobility in Hungary during the spring of 2020. From the environmental perspective, the obtained road traffic reduction of 20–50% could be regarded as an undesired traffic regulation experiment. Air quality impacts within Hungary were evaluated based on data from 52 monitoring sites measuring concentrations of pollutants NOx, O3, and PM10. Air pollution during the lockdown was compared to the same period (February–June) in the reference years 2014–2019. The large spatial heterogeneity of the air quality response was explored. The emission reduction coincided with the extreme weather of 2020, characterized by unusually warm pre-lockdown February and spring drought. The anomalously low pre-lockdown air pollution was further reduced (NOx) or increased (PM10) during the restrictions. Compared to the previous years, NOx concentrations during the curfew were found to differ between −4.1 and +0.2 standard deviations (median −1.55 SD), or −45% and +3% (median −18%) among different monitoring locations. Ozone concentrations were unusually high due to both weather and chemical reasons (median +11% or +0.8 SD), while the PM10 response was modest and largely weather-driven (median +7% or +0.4 SD).

How Covid-19 pandemic influenced air quality in Polish cities – lessons from three lockdowns

“…However, the air quality improvement effect was not seen everywhere and for all pollutants. In Hungary, although NO x concentrations dropped up to 45%, the PM10 level even slightly increased (+ 7%) at the beginning of the first lockdown and was rather weather-driven (Varga-Balogh et al, 2021). Chen et al (2020) noticed that both NO 2 and CO levels were dropping in US cities (up to 49% and 37% respectively) and tended to increase with local population density, while significant reductions of particulate matter occurred seldom and only in those cities with highest NO 2 decline.…”

“…As a consequence of stay-at-home orders and decrease in vehicle usage, especially traffic emission was limited, what resulted in much lower NO 2 and NO x concentrations recorded all over the world (Venter et al, 2020;Briz-Redón et al, 2021;Dong et al, 2021;El-Sayed et al, 2021;Ropkins & Tate, 2021;Varga-Balogh et al, 2021;Wyche et al, 2021). However, the air quality improvement effect was not seen everywhere and for all pollutants.…”

“…Numerous studies show that lockdowns caused air pollution to decrease (Brimblecombe & Lai, 2020;Dong et al, 2021;Dutheil et al, 2020;Gautam, 2020;Liu et al, 2021;Rodríguez-Urrego & Rodríguez-Urrego, 2020;Rossi et al, 2020;Skirienė & Stasiškienė, 2021;Varga-Balogh et al, 2021). However, many of them have only considered the first lockdown, happening between March and May 2020 in most countries (e.g.…”