The air mass back-trajectory clustering analysis was combined with Aerosol Optical Depth (AOD) of fine mode, coarse mode and fine mode fraction in order to evaluate the long-range effects of transportation patterns of trajectories for the ground based station at ICIPE Mbita which is located on longitude and latitude of 34.2буE, 0.417буS respectively at 1125 meters above sea level. In order to get a clear picture of the source and sinking points of aerosols, monthly means of a 72 hour backward trajectories data ranging from 2013 to 2015 were used in categorizing the cluster into five classes. Most of the air trajectories analysis from this paper shows evidence that the major sources and pathways for the aerosols into the receptor station commonly originate from as far as the Arabian deserts and Sahara deserts from the Northern Hemisphere and Indian Ocean and central Africa in the Southern Hemisphere.