Free space optical (FSO) communication is a line of sight technology capable of carrying large volume of data using laser signals through the atmosphere. This unguided propagation of laser beams through the atmosphere confronts with turbulent fluctuations and suspended aerosol particles on its en route to the receiver. Random fluctuations in the atmospheric refractive index causes variations in the propagation constant and thereby affects the optical pulse propagation. We examine the local atmospheric warming effects of absorbing aerosols on the atmospheric refractive index fluctuation statistics and its influence on the group velocity dispersion (GVD) parameter. Black Carbon (BC) aerosols increase local temperature through solar absorption, which will be amplified when they reside in the upper atmosphere for longer duration, owing to the reduced atmospheric density prevailing at higher altitudes. To elucidate the implications of elevated BC layer heating on FSO links, vertical BC mass concentration was measured using an Aethalometer (Model AE-42, of Magee Scientific, USA) mounted on a hydrogen filled balloon. Long term analysis of multi-satellite observations along with in-situ measurements of aerosol parameters show dependence of GVD on aerosol induced local atmospheric warming. Effect of warming on outage probability of FSO systems employing chirped Gaussian pulses are also presented.