ABSTRACT
The study assesses the concentration of NO2 and CO pollutants using in Onitsha, Eruna Lagbe and Iyiowa Odakpe in Anambra state using Sentinel-5P satellite before, during and after COVID-19. COVID-19 originated from China in December 2019. In an attempt to control its spread and reduce health impact, several countries especially Nigeria imposed restrictive measures that was termed ‘Lockdown’ which beneficial to air quality. A secondary data was used for this study and were also obtained through a software known as Google Earth Engine. A script of extraction is peculiar to Sentinel-5P extraction was inputted in the engine to easy the extraction of these image. After the extraction of the raster image and downloaded through the help of Google Drive, they were analyzed and processed using ArcGIS 10.4, a Geographic Information System software.
In this study, the level of NO2 and CO was assessed. It was noticed that NO2 mean value of 0.000076 first quarter, 0.000054 second quarter, 0.000068 third quarter for 2019, 0.000072 first quarter,0.000053 second quarter, 0.000074 third quarter for 2020 and 0.000078 first quarter, 0.000065 second quarter, 0.000082 third quarter for 2021. This revealed a rise and fall progression of these value showing statistical difference in air pollution across the three years. The fall in air pollution value from 2019, to 2020 and from 2019 to 2020 and 2021 could be attributed to compliance to COVID-19 lockdown, restriction of transportation movement and commercial activities, while the rise in 2021 could be as a result of resumption of activities like market operation, transportation and commercial activities. The problem associated with rise in the concentration of NO2 could be respiratory illness, and premature death etcm. In CO, it was noticed that the mean value of 0.063 first quarter, 0.043 second quarter, 0.045 third quarter for 2019, 0.065 first quarter, 0.044 second quarter, 0.047 third quarter for 2020, 0.0617 first quarter, 0.045 second quarter, 0.045 third quarter for 2021. This revealed the rise and fall progression of these values showing variations in air pollution across the three years. The fall in air pollution values from 2019 to 2020 depict compliance with COVID-19 lockdown which could affect restriction of commercial activities, also CO in 2021 depict steady of commercial activities and restriction of transportation. The problem associated with CO could be headaches and reduced mental alertness. The limitation associated with this method of data collection is lack of base data collection and therefore, there should be more research on this work to enable be up to date in air pollution.
