Exploring the Impact of Covid-19 on Air Quality Using Sentinel-5P and MODIS Data in Ho Chi Minh City

The Corona virus disease in 2019 (Covid-19) has come up with serious consequences in public health all over the world, and especially in Ho Chi Minh City (HCMC). During the pandemic, the city needs to do quarantine activities to control the spread of the virus. This study focuses on exploring the impact of the Covid-19 outbreaks on the air quality by the concentration of pollutants including Sulphur Dioxide (SO2), Nitrogen Dioxide (NO2), and Ozone (O3) derived from Sentinel-5P TROPOMI data, and Particulate matter is at and under 2.5 mm of diameter (PM2.5) estimated from MODIS Aerosol Optical Depth (AOD) data. The duration of the research is from 1st January 2020 to 31st December 2022, and separated into 2 parts, based on the dry season and the wet season for the case study of Ho Chi Minh city. As a result, it shows the decrease in different level of air pollutants, including the significant decline in NO2 (up to 15.27%), SO2 (up to 46%), and PM2.5 (up to 25.46%), while the O3 layer suffered minor change of 1.75% in increasing. The results are expected to provide an understanding of the geospatial distribution of the air pollutants before and after the Covid-19 lockdown periods in HCMC. Moreover, it also confirms that deploying air quality monitoring systems with ground stations and satellite observations is effective.