Environmental spatial heterogeneity of the impacts of COVID-19 on the top-20 metropolitan cities of Asia-Pacific

Ghaffar Ali,Faisal Mueen Qamer,Sawaid Abbas,Syed Muhammad Irteza

doi:10.1038/s41598-021-99546-9

Abstract

This study investigated the environmental spatial heterogeneity of novel coronavirus (COVID-19) and spatial and temporal changes among the top-20 metropolitan cities of the Asia-Pacific. Remote sensing-based assessment is performed to analyze before and during the lockdown amid COVID-19 lockdown in the cities. Air pollution and mobility data of each city (Bangkok, Beijing, Busan, Dhaka, Delhi, Ho Chi Minh, Hong Kong, Karachi, Mumbai, Seoul, Shanghai, Singapore, Tokyo, Wuhan, and few others) have been collected and analyzed for 2019 and 2020. Results indicated that almost every city was impacted positively regarding environmental emissions and visible reduction were found in Aerosol Optical Depth (AOD), sulfur dioxide (SO2), carbon monoxide (CO), and nitrogen dioxide (NO2) concentrations before and during lockdown periods of 2020 as compared to those of 2019. The highest NO2 emission reduction (~ 50%) was recorded in Wuhan city during the lockdown of 2020. AOD was highest in Beijing and lowest in Colombo (< 10%). Overall, 90% movement was reduced till mid-April, 2020. A 98% reduction in mobility was recorded in Delhi, Seoul, and Wuhan. This analysis suggests that smart mobility and partial shutdown policies could be developed to reduce environmental pollutions in the region. Wuhan city is one of the benchmarks and can be replicated for the rest of the Asian cities wherever applicable.

Highlights

This study investigated the environmental spatial heterogeneity of novel coronavirus (COVID-19) and spatial and temporal changes among the top-20 metropolitan cities of the Asia-Pacific
Some studies have reported the air quality correlated with COVID-197–10, some investigated its correlation with w eather[11,12]; likewise, an interesting study compiled the information released by National Aeronautics and Space Administration (NASA) on pollution across the g lobe[13] based on the maps released by the NASA and European Space Agency (ESA)
The first COVID-19 lockdown in the world was imposed in Wuhan city on 21st January 2020 and the latest was in Singapore, on 7th April 202019

Summary

Introduction

This study investigated the environmental spatial heterogeneity of novel coronavirus (COVID-19) and spatial and temporal changes among the top-20 metropolitan cities of the Asia-Pacific. A 98% reduction in mobility was recorded in Delhi, Seoul, and Wuhan This analysis suggests that smart mobility and partial shutdown policies could be developed to reduce environmental pollutions in the region. out of the world’s most polluted cities are present in the Asian r egion[15], it is necessary to understand the environmental dynamics of such metropolitan cities relating to COVID-19 This wave of lockdown following pandemic is interlinked. Keeping in view all these facts and research gap, this study investigated the environmental spatial heterogeneity of COVID-19 and spatial and/or temporal changes among the top-20 ( onwards T20) metropolitan cities of the Asia-Pacific

Objectives

Methods

Results

Discussion

Conclusion