A Color Ratio Method for Simultaneous Retrieval of Aerosol and Cloud Optical Thickness of Above-Cloud Absorbing Aerosols From Passive Sensors: Application to MODIS Measurements

The presence of absorbing aerosols above cloud decks reduces the amount of upwelling ultraviolet (UV), visible (VIS), and shortwave infrared radiation reaching the top of atmosphere. This effect is often referred to as “cloud darkening,” which can be seen by eye in images and quantitatively in the spectral reflectance measurements made by passive sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS) in the regions where...