1.1 AQI and Economic Growth
For any country at its initial stage of development, economic growth is directly linked to the degradation of an environment as it demands intense energy production which results in the increment of pollutants in the environment. It is found that the impact of economic growth on environmental pollution can be categorized into four relationships that are inverted U-shaped, N-shaped, a monotonically increasing relationship, U-shaped relationship. But later this proportionality can be reduced through knowledge and awareness, framing rules and regulations, gradually replacing outdated techniques by upgrading them, and improving the industrial structure (Basahi, J.M. et al., 2014); (Rastogi, R. et al., 2020b); (Rastogi, R. et al., 2021b); (Rastogi, R. et al., 2022a).
Framing rules and regulation requires regional level research which includes an understanding of regional relationship factors between economic growth and environmental pollution as environmental pollution varies from one region to another. It is observed that in developing countries the level of pollution in metropolitan cities is higher than that of non-metropolitan cities. Today most of the developing countries are facing problems of air pollution. Air pollution is mainly due to excessive content of Sulphur dioxide in the atmosphere causing severe respiratory problems, acid rain, global warming (Jiang, M. et al., 2020); (Carlowicz, M. et al., 2009); (Rastogi, R. et al., 2020c); (Rastogi, R. et al., 2021c); (Rastogi, R. et al., 2022b).
1.2 AQI and Disease Correlation with Pandemics
Recently COVID’19 originated as one of the terrible pandemic and in its case study, it has been found that both meteorological factors and air pollution have played a vital role in its spreading. Meteorological factors such as wind, temperature, and relative humidity. With a rise in temperature in an average range of 0.56 to 0.78, COVID’19 shows a positive effect as cases were seen to be more in the summer and dry season. Relative humidity shows quite a low relation in the range of 0.14 to 0.52. Wind acts as both a spreader of virus in Brazil and a reducer as in Indian states such as New Delhi the COVID cases have started to decrease. Uttar-Pradesh, New Delhi, Karnataka, Tamilnadu, Andhra Pradesh, and Maharashtra are the states in which pollution levels remain at peak throughout the year but during the lockdown, there was an observable decrease in AQI level, and the COVID case was also started to be decreased. An improvement can be seen in the environment, water bodies, land, and human health (Gautam, S. et al., 2021); (Camfil, 2018); (Rastogi, R. et al., 2020d); (Rastogi, R. et al., 2021d); (Rastogi, R. et al., 2022c).