Impacts of nationwide lockdown due to COVID-19 outbreak on air quality in Bangladesh: a spatiotemporal analysis

Abstract

In Bangladesh, a nationwide lockdown was imposed on 26 March 2020, due to the COVID-19 pandemic. Due to restricted emissions, it was hypothesized that the air quality has been improved during lockdown throughout the country. The study is intended to assess the impact of nationwide lockdown measures on air quality in Bangladesh. We analyzed satellite data for four different air pollutants (NO 2 , SO 2 , CO, and O 3) to assess the changes in the atmospheric concentrations of pollutants in major cities as well as across the country. In this study, the concentrations of NO 2 , SO 2 , CO, and O 3 from 1 February to 30 May of the year 2019 and 2020 were analyzed. The average SO 2 and NO 2 concentrations were decreased by 43 and 40%, respectively, while tropospheric O 3 were found to be increased with a maximum of > 7%. Among the major cities, Dhaka, Gazipur, Chattogram, and Narayanganj were found to be more influenced by the restricted emissions. In Dhaka, NO 2 and SO 2 concentrations were decreased approximately by 69 and 67%, respectively. Our analysis reveals that NO 2 concentrations are highly correlated with the regional COVID-19 cases (r = 0.74). The study concludes that the lockdown measures significantly reduced air pollution because of reduced vehicular and industrial emissions in Bangladesh.

Impact of COVID-19 lockdown upon the air quality and surface urban heat island intensity over the United Arab Emirates

“…The analysis showed that the six Emirates experienced a decline in NO 2 levels because of restricted transportation and factories' closure. This result is compatible with other earlier studies undertaken in various regions around the globe ( Baldasano, 2020 ; Dantas et al, 2020 ; Islam et al, 2020 ; Kaplan and Avdan, 2020 ; Sharma et al, 2020 ). Fig.…”

“…These results are in accordance with the results of previously published research. Islam et al (2020) recorded identical outcomes for Bangladesh, Agarwal et al (2020) recorded an average reduction in NO 2 during the lockdown in China by 49% and in Mumbai (India) by more than 76%. In the Middle East (Morocco), NO 2 levels were decreased during the lockdown phase as well ( Sekmoudi et al, 2020 ).…”

“…The emergent Coronavirus disease 2019 (COVID-19) is a transmittable disorder characterized by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) ( Islam et al, 2020 ). By massive human-to-human transmission, COVID-19 has deeply hit the world and prompted a spike in the human mortality rate and massive economic casualties around the world ( Bukhari and Jameel, 2020 ).…”

“…Likewise, during the COVID-19 pandemic, many other recent studies show a significant decline in the level of air pollutants such as NO 2 , SO 2 , PM 10 , PM 2.5 , CO, etc. globally ( Archer et al, 2020 ; Collivignarelli et al, 2020 ; Dantas et al, 2020 ; Islam et al, 2020 ; Kaplan and Avdan, 2020 ; Kerimray et al, 2020 ; Nakada and Urban, 2020 ; Ranjan et al, 2020a ; Wang and Su, 2020 ). However, while studies generally showed a reduction in the primary pollutants, some studies showed no reduction in air pollution.…”

Association of COVID-19 distribution with air quality, sociodemographic factors, and comorbidities: an ecological study of US states

“…The air pollution associations revealed in this study were similar to that of prior studies in USA (Liang et al 2020). A higher value of CFR and PCD was significantly associated with exposure to NO 2 , but not O 3 and PM 2.5 (Liang et al 2020;Anil and Alagha 2020;Islam et al 2020). On the other hand, Wu et al 2020 showed that only 1 μg/m 3 increase in PM 2.5 was associated with an eighth percent increase in the COVID-19 death rate.…”