Analyzing Seasonal Variations in Air Quality with Google Earth Engine: A Case Study of Chattogram, Bangladesh

MD. Minaruzzaman Shovon , Md. Tamim

Air pollution is a serious environmental challenge in Bangladesh, significantly
affecting public health and the ecosystem. This study considers analyzing the seasonal
fluctuation of air quality in Chattogram by analyzing 13 significant areas near the industrial
zone by using Google Earth Engine (GEE) to explore the SENTINEL-5P satellite data for key
pollutants, including nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO),
and QGIS for mapping purposes. The datasets were assessed through four different seasons:
winter (December - February), pre-monsoon (March - June), monsoon (July - September), and
post-monsoon (October - November). It is found that significant trends over the seasons—
where the winter shows the maximum level of pollutant concentrations, i.e., NO2 shows
0.000200 mol/m2 in Patiya and 0.000059 mol/m2 at Bayezid Bostami in the monsoon, and SO2
shows 0.000394526 mol/m2 in Chittagong Port and 0.0000152 mol/m2 in the monsoon period
in Bakalia. The variation intensely indicates the changes in concentrations of pollutants over
the season and has a strong negative correlation between precipitation, temperature, humidity,
and wind velocity. The monsoon season enhances air quality, effectively dispersing rainfall and
significantly lowering pollutant levels. Furthermore, the analysis highlights the hotspots or
sources of the pollutant all over the year. This study enhances policymakers' understanding of
urban air quality by providing actionable strategies to reduce air pollution.