The knowledge of the tropospheric concentration distribution of atmospheric tracerngases such as methane and of its temporal evolution allows us to understand chemicalrnprocesses controlling the atmospheric composition and to estimate the potential contributionrnof each gas to the climate forcing of the Earth-atmosphere system. Equally,rnaerosols play an important role in the climate system; the effect of aerosols on thernglobal climate system is one of the major uncertainties of present climate predictions.rnThey play a major role in atmospheric chemistry and hence affect the concentrationsrnof other potentially harmful atmospheric constituents. We have extracted and characterizedrnthe volume mixing ratio(VMR) of methane over the equatorial region fromrnthe spectral records of ground-based high spectral resolution of FTIR. For this work,rnthe spectral data from the FTIR measurement campaign in October and Novemberrn1996 over the Atlantic Ocean covering the region of our study have been used. Thernretrieval result has given good quality of methane VMR over most of the regions.rnBut unhealthy enhancement is seen in the regions 200 South which is attributed tornthe poor quality of inputs. In addition, comparison of VMR data of Halogen OccultationrnExperiment (HALOE) satellite with our retrieved VMR data from FTIR hasrnconfirmed good agreement over most of the latitude covered by this study and slightrndiscrepancy at certain latitude. With respect to aerosols, the SAGE II instrumentrnhas collected vertical profiles of stratospheric and tropospheric aerosol extinction atrnfour wavelengths with high resolution since the programâ€™s inception in October, 1984.rnWe extracted the aerosol parameter; the aerosol extinction coefficients derived fromrnversion 6.20 series of twenty one years data to characterize the aerosol climatologyrnviiirnixrnof Africa. Accordingly, from monthly mean extinction profile, we have seen a largernvalue of aerosol concentration over troposphere of the Northern, Southern and Easternrnregions. Unlike the other two above mentioned regions a large value of aerosol isrnobserved in the lower stratosphere of Eastern region. These cloud of aerosol extinctionrncoefficient is observed at the end of winter and during the summer season of thernrespective region