Anyika, L. C.Alisa, C. O.Nkwoada, A. U.Opara, A. I.Ejike, E. N.2025-05-062025-05-062020-06-29Anyika, L. C., Alisa, C. O., Nkwoada, A. U., Opara, A. I. & Ejike, E. N. (2020). Spatio-temporal study of criteria pollutants in Nigerian city. Asian Journal of Applied Chemistry Research, 6(3), 1-132582-027310.9734/AJACR/2020/v6i330160https://repository.futo.edu.ng/handle/20.500.14562/1838An original research article with figures and tablesAims: An investigation of characteristic long term air pollutants known for temporal and spatial behaviors was conducted due to increased pollution scenarios in Nigerian cities as a result of deprived environmental enforcement of statutory obligations. Study Design: One of the worlds’ most polluted cities (Onitsha lower basin) in Nigeria was selected for spatio-temporal study of three criteria pollutants combined with GIS and MATLAB alongside associated meteorological conditions during harmattan. Methodology: 72-hourly analyses of the nine different locations having 4 sampling sites and 500 meters apart were done from December to February which generated over 19, 440 experimental data per quarter of each annual study. Results: Upper Iweka/Nitel area recorded the highest concentration of SO2 pollutant at (94.2 µg/m3) due to longer residence times and low wind mixing height. Borromeo hospital showed the least active NO2 region but converges at points 1 due to North-east wind dissimilar to sampling points 1 having the lowest PM10 distribution. Measured temperature parameter correlates inversely with relative humidity and precipitation. The GIS spatial representation corresponded to temporal variability of gaseous and particulate pollutants. Conclusion: All sampled areas had AQI above 50; hence the study identified SO2, NO2, and PM10 as Primary pollutants of Onitsha lower basin.enAttribution-NonCommercial-ShareAlike 4.0 InternationalAir qualityGISharmattanMATLABseasonal variationsair pollutantsmeteorologyDepartment of ChemistryArticle