The impact of enhanced local heating due to absorption of solar radiation by elevated layers of aerosol black carbon (BC) in the lower troposphere in the performance of free-space optical (FSO) communication links is investigated. It is seen that a strong elevated BC layer at an altitude around 4.5 km enhances the atmospheric stability locally and leads to a large reduction in the atmospheric refractive index structure parameter (Cn2), leading to improved performance of the FSO communication links. For layers in the tropical atmosphere with sufficiently high BC concentration, the signal attenuation due to BC absorption is alleviated by the large reduction in Cn2 due to BC-induced warming and brings down the link outage probability. Synergy between reduction in Cn2 and long wavelength transmission improves the link budget significantly by reducing the beam wander and number of adaptive optics units required.

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http://dx.doi.org/10.1364/AO.57.007152DOI Listing

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