The Nexus Between Air Pollution and the COVID-19 Pandemic in Turkey: Further Insights from Wavelet Coherence Analysis

The nexus of the ambient air quality and the COVID-19 pandemic is a topic that has attracted much attention and remains of current interest. The study area of Turkey is one of the countries with high case numbers, but there is no detailed investigation dealing with it in the literature. For this reason, the correlation and links between COVID-19 cases and deaths in Turkey with the air pollutants of PM10, PM2.5, SO2, CO, NO2 and O3 were determined between 1 April and 31 July 2021 using the statistical methods of cross-correlation and wavelet coherence analysis. According to the findings, for the COVID-19 pandemic parameters, there were positive significant correlations with PM2.5, SO2, CO, and NO2 and an inverse significant correlation with O3. Although the wavelet transform is not convincing to suggest a standalone coherence, it reveals that air pollution and the spread and mortality of the pandemic in Turkey have short-term periods of co-movement. Additionally, it is notable that the national air quality improved during full lockdown periods in the country. The findings obtained in this study are expected to attract the attention of legislating and enforcing authorities and support more decisive steps being taken to reduce environmental pollutants and to control air pollution.