Determining the relationship between air pollution and urbanization and COVID-19 using geographical information systems

Air pollution is one of the most important environmental problems that disrupts the ecological balance and harms human health. With urbanization, the increase in population, industrialization, fossil fuel use, traffic, agriculture and harmful gases formed by unplanned urbanization accumulate in the atmosphere, reducing air quality and causing an increase in respiratory diseases. In recent years, the relationship between air pollution and respiratory diseases such as COVID-19 has increased the importance of air pollution in terms of public health. Therefore, protecting air quality is of great importance for a livable environment and healthy societies. In this thesis, the relationship between air pollution and the COVID-19 pandemic was examined by analyzing satellite data obtained through remote sensing in the Geographic Information Systems (GIS) environment. The aim of the study was to analyze the relationship between air pollution, urbanization and COVID-19 cases using remote sensing data and GIS techniques. In the analyses conducted throughout Türkiye and specifically for five metropolitan cities (Istanbul, Ankara, Izmir, Bursa, Antalya), data on carbon monoxide (CO), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂) air pollutants between 2019 and 2022 were obtained from the Sentinel-5P satellite images using Google Earth Engine (GEE) platform. Satellite data were processed as monthly averages by applying the borders of Türkiye and cloud mask and then converted into thematic maps. The CO, SO₂, NO₂ data obtained from air quality monitoring stations of the Ministry of Environment, Urbanization and Climate Change and satellite data were compared. COVID-19 case data were examined by converting weekly-based data from 2021 to monthly data and performing graphical analyzes, and multiple regression analysis was performed to see the relationship between the received data and the satellite data of five metropolitan cities. Station data for five metropolitan cities were compared with satellite data corresponding to the same points, and thus the consistency between the two data sources was analyzed. Urban settlement areas and thermal power plant data were spatially mapped and evaluated together with satellite images. The relationships between socio-spatial variables such as organized industrial zone (OSB) areas, thermal power plants, and population and COVID-19 cases were examined. These findings show that air pollution is not only an environmental problem but also important for public health. The obtained results are guiding in terms of urban planning and environmental management. As a result of the analysis, statistically significant relationships were determined between some pollutants and the number of COVID-19 cases; it was observed that the cases were related to poor air quality. On the other hand, it has been revealed that restrictions imposed during the pandemic have led to improvements in air quality. The study once again reveals the effects of air pollution on public health and shows that more importance should be given to air quality in urban planning.