Spectral and Statistical Analysis of Nitrogen Dioxide and Sulphur Dioxide Air Pollutants using Wavelet Transforms

Due to high population growth, unplanned urbanization, unsystematic transportation and unscientific lifestyle the air pollution has become a great challenge for human beings. Nitrogen dioxide and Sulphur dioxide are hazardous air pollutants for health and environment. The quantitative behaviour of Nitrogen dioxide and Sulphur dioxide before lockdown (from 01-01-2018 to 31-12-2019) and after lockdown (01-06-2020 to 31-07-2020) as a case study ofMoradabad, Uttar Pradesh are spectrally and statistically analyzed using Haar wavelet transforms. The approximation corresponding to highest scale value represents the average behaviour or trend of a signal, while details explore the fluctuations in signal in a more clear way. The appreciable decrease in air pollutants is observed which indicated the positive effect of lockdown in the context of environment. The interpretation of statistical parameters of the given data provides the strong agreement in the favour of wavelet analytical results.