Assessment of Relationship Between Meteorological Parameters and Air Quality Index of Kota, Rajasthan, India

Abstract

Meteorological parameters extremely influence the air quality of metropolitan cities worldwide. This study analyses the impact of meteorological variables on the quality of air for the Kota metropolis of Rajasthan (India) from 2018 to 2021 for four years. Wind speed and direction, relative humidity, precipitation, and temperature are the meteorological parameters selected to statistically determine the effect of meteorological variables on the AQI (air quality index). The AQIs are evaluated through PM10, PM2.5, NO2, and SO2. The average concentration of PM10 was 122.59 ± 44.11µg/m3, PM2.5 was 56.83 ± 24.89 µg/m3, NO2 was 24.91 ± 4.99 µg/m3, and SO2 was 7.39 ± 1.38 µg/m3 during the observation period. The average temperature varied between 18-38 °C in 2018, 15.7-34.8 °C in 2019, 15.5-35.1 in 2020, and 16.8-32.4 °C. Total rainfall in 2018, 2019, 2020, and 2021 was 685 mm, 1637 mm, 514 mm, and 1338 mm, respectively. The average wind speed in the city were 1.39, 1.30, 1.26, and 1.22 m/s in 2018, 2019, 2020, and 2021, respectively. The relative humidity ranged from 17-78 % in 2018, 22-84% in 2019, 40-90 % in 2020, and 24-82 % in 2021. The annual average AQI of Kota was 139, 118, 101, and 142 in 2018, 2019, 2020, and 2021, respectively. There is a statistically significant correlation between temperature and AQI (p<0.05), rainfall and AQI (p<0.05), and wind speed and AQI (p<0.05), which show a significant impact on the air quality of the Kota metropolis. At the same time, there is a statistically insignificant correlation between relative humidity and AQI (p>0.05), which shows an insignificant impact on air quality. The formulated equation for predicting AQI through meteorological parameters has wide scope utility in air pollution management and control.