Temporary reduction in fine particulate matter due to 'anthropogenic emissions switch-off' during COVID-19 lockdown in Indian cities.
Sustain Cities Soc
; 62: 102382, 2020 Nov.
Article
em En
| MEDLINE
| ID: mdl-32834936
ABSTRACT
The COVID-19 pandemic elicited a global response to limit associated mortality, with social distancing and lockdowns being imposed. In India, human activities were restricted from late March 2020. This 'anthropogenic emissions switch-off' presented an opportunity to investigate impacts of COVID-19 mitigation measures on ambient air quality in five Indian cities (Chennai, Delhi, Hyderabad, Kolkata, and Mumbai), using in-situ measurements from 2015 to 2020. For each year, we isolated, analysed and compared fine particulate matter (PM2.5) concentration data from 25 March to 11 May, to elucidate the effects of the lockdown. Like other global cities, we observed substantial reductions in PM2.5 concentrations, from 19 to 43% (Chennai), 41-53% (Delhi), 26-54% (Hyderabad), 24-36% (Kolkata), and 10-39% (Mumbai). Generally, cities with larger traffic volumes showed greater reductions. Aerosol loading decreased by 29% (Chennai), 11% (Delhi), 4% (Kolkata), and 1% (Mumbai) against 2019 data. Health and related economic impact assessments indicated 630 prevented premature deaths during lockdown across all five cities, valued at 0.69 billion USD. Improvements in air quality may be considered a temporary lockdown benefit as revitalising the economy could reverse this trend. Regulatory bodies must closely monitor air quality levels, which currently offer a baseline for future mitigation plans.
AOD, aerosol optical depth; AQI, air quality index; Air pollution; CO, carbon monoxide; CO2, carbon dioxide; COVID-19, Coronavirus disease 2019; Coronavirus pandemic; EPA, Environmental Protection Agency; ER, excess risk; ESA, European Space Agency; Emission switch-off; GEV, generalized extreme value; GoI, Government of India; HB, health burden; Health and economic impacts; MODIS, moderate resolution imaging spectroradiometer; MSL, mean sea level; NASA, National Aeronautics and Space Administration; NH3, ammonia; NO2, nitrogen dioxide; O3, ozone; PDF, probability density function; PM, particulate matter; PM10, PM with aerodynamic diameter of ≤ 10 µm; PM2.5 concentration; PM2.5, PM with aerodynamic diameter of ≤ 2.5 µm; RH, relative humidity; RR, relative risk; SARS-CoV-2 Virus; SARS-CoV-2, Severe Acute Respiratory Syndrome Coronavirus 2; SO2, sulphur dioxide; SSEC, Space Science and Engineering Centre; TROPOMI, TROPOspheric monitoring instrument; UK, United Kingdom; USA, United States of America; USD, United States Dollar; VSL, value of statistical life; WHO, World Health Organization
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Base de dados:
MEDLINE
Tipo de estudo:
Etiology_studies
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article