Airborne Doppler Lidar Investigation of Sea Surface Reflectance at a 355-nm Ultraviolet Wavelength

Abstract The analysis of the sea surface reflectance for different incidence angles based on observations of an airborne Doppler lidar at an ultraviolet wavelength of 355 nm is described. The results were compared to sea surface reflectance models, including the contribution from whitecaps, specular reflection, and the subsurface volume backscattering. The observations show the expected effect of the wind stress on the sea surface reflectance and allow new insights into the significant contribution from subsurface reflectance for large incidence angles. While most of the observations and model results were obtained for isotropic reflectance, first results on anisotropic reflectance are also provided. The results from this study are relevant to future spaceborne wind lidar instruments, for example, the Atmospheric Dynamics Mission (ADM)-Aeolus, which could use the sea surface reflectance for the calibration of intensity and wind.

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