Validation of Satellite-Retrieved Oceanic Inherent Optical Properties: Proposed Two-Color Elastic Backscatter Lidar and Retrieval Theory

Recent radiative transfer models show that: (1) regardless of elastic lidar receiver field of view (FOV), at vanishing lidar depth the lidar-derived attenuation coefficient klidar ? a , where a is the total absorption coefficient per meter of depth; and (2) for a wide FOV as the lidar sensing depth approaches some large value (depending on water type), klidar ? Kd , where Kd is the diffuse attenuation for downwelling irradiance. As a result, it is shown that a time-resolved, dual-wavelength-laser, elasticbackscattering lidar can retrieve the three principal oceanic optical properties: (1) the absorption coefficient of phytoplankton aph , (2) the absorption coefficient of chromophoric dissolved organic matter (CDOM) aCDOM , and (3) the nonwater total constituent backscattering coefficient bbt . The lidar-retrieved aph , aCDOM , and bbt inherent optical properties can be used to validate corresponding satellite-derived products such as those from terra moderate-resolution imaging spectroradiometer (MODIS), Aqua MODIS, Sea-viewing Wide Field-of-view Sensor, (SeaWiFS), and other ocean color sensors.