Appraising the effects of atmospheric aerosols and ground particulates concentrations on GPS-derived PWV estimates

摘要

In 2016, three Nigerian cities were listed amongst the World's most polluted in terms of particulate matter (PM). Acknowledging Nigeria's limited resources for outdoor air pollution monitoring, this study attempts to investigate the effects on atmospheric aerosol optical depth and ground PM on GPS derived-precipitable water vapour estimates. The study utilized available GPS-derived precipitable water vapour (GPS(PWV)), the moderate resolution imaging spectroradiometer aerosol optical depth (MODISAOD) and the ground level particulate matter of less than 10 mu m (GPM) datasets for December 2015-November 2016. All the datasets were tested for normality. To evaluate the atmospheric aerosol properties, the MODISPWV estimates were pre-validated using the GPS(PWV) measurements. The results revealed GPS(PWV)-MODISPWV agreement (R = 0.964; RMSE = 3.810 mm). The GPS(PWV)-MODISAOD analysis showed relationship (R = -0.636; RMSE = 0.563) for the atmospheric aerosol experiment, while the collocating GPS(PWV)-GPM seasonal analysis also revealed significant correlation (R -0.660). The correlation of combined seasonal datasets for the GPS(PWV)-MODISAOD and GPS(PWV)-GPM relationships showed high negative correlation values of 0.79 and 0.68 respectively. The findings of this study is in agreement with similar related studies, as well as serve as position accuracy for future related studies.