Substantial spatial and temporal variabilities in chemical and physical properties of aerosols complicate attempts to model associated influences on global climate. Although wet deposition is the major mechanism by which most aerosols are removed from the atmosphere, direct effects of precipitation on radiative properties of the atmosphere are not well understood. To address this issue, attenuation coefficients for total insoluble constituents (ACt) and for nonvolatile (at 500¿C) insoluble constituents (ACnv; primarily crustal dust) of precipitation at Bermuda and Barbados were measured at six wavelengths between 414 and 859 nm. Coefficients for volatile (at 500¿C) insoluble constituents (ACv; primarily carbonaceous species) were calculated by difference. Between April and September, ACt at Bermuda was dominated by mineral constituents transported from North Africa, whereas carbonaceous species from North America were relatively low and exhibited no systematic seasonal variability. ACt and ACnv at Barbados were dominated by mineral dust, especially between April and September. Relative to ACv, ACnv decreased more rapidly with increasing wavelength. The wavelength dependencies of ACs for volatile and nonvolatile constituents at Bermuda were statistically indistinguishable from those at Barbados. The optical and chemical characteristics of precipitation were compared with scattering and absorption by ambient aerosols in associated air parcels to evaluate the influence of scavenging on the radiative properties of air. Although discernible relationships were evident, the small number of cases limited their applicability as reliable empirical predictors. However, these data do provide useful constraints for validating models of aerosol scavenging and wet removal on the optical properties of the troposphere.