Spatial distribution of the atmospheric transmission over the Atlantic Ocean is discussed based on the results of five research missions (1989-1996). The transmission inhomogeneities are shown to be mostly due to variations of the atmospheric aerosol optical thickness affected by the carry-over of continental aerosol. The carried over aerosol is small-sized in midlatitudes and coarse disperse one in the trade-wind zone. The characteristics of moisture content variability and the height of homogeneous layers in the atmosphere are presented and the necessity to distinguish between two latitude zones in tropics is underlined. A model of the transmission spatial distribution is proposed based on the consistent results of genetic and descriptor-based zoning of the atmospheric aerosol turbidity. Peculiarities of the spectral behavior of aerosol optical thickness are treated and its parameters in 0.37-1.06 and 0.37-4 mkm are determined for different oceanic regions. The contribution from fine and coarse aerosols to the aerosol optical thickness and total transmission of the atmosphere are discussed.