Spatiotemporal Variation of Fine Particulate ...

Spatiotemporal Variation of Fine Particulate Matter (PM2.5) and Meteorological Parameters over Different Cities of Uttar Pradesh

Author Name : Sumit Singh, Amarendra Singh, A.K. Shukla, Osama Siddiqei

ABSTRACT Spatiotemporal characteristics of atmospheric fine particulate matter (PM2.5) and its co-relationship with meteorological parameters over four different cities, viz., Agra, Moradabad, Lucknow and Varanasi in Uttar Pradesh were statistically analyzed using the daily PM2.5 mass concentrations and surface meteorological parameters measured by air quality monitoring stations of Central Pollution Control Board (CPCB) from Jan 2017 to Dec 2019. Planetary boundary layer height (PBLH) remote-sensed satellite data of Modern-Era Retrospective Analysis for Research and Application (MERRA 2) was also included in the study. High peaks in daily PM2.5 concentrations were observed during the months of October-December and February-March. The monthly averaged PM2.5 concentration ranged from 18.9 to 277.9 μg m-3 in most polluted city of Varanasi. The annual averaged PM2.5 concentrations have shown a decreasing trend throughout the study period for all the selected cities. Negative correlations were observed for wind speed (R = -0.6), relative humidity (R = -0.6), PBLH (R = -0.5) against PM2.5 concentrations as high wind speeds and high mixing layer height helps in the better horizontal and vertical dispersion of air particles. PM2.5 shows strong positive correlation with surface air pressure as high air pressure restricts the movement of air particles in upward direction leading to an accumulation of particulate matter. In overall, the correlations with meteorological parameters varied across different seasons of the year along with the spatial variation of PM2.5 concentrations.