Mobley, C. D.. Sequoia Scientific, Inc., mobley@sequoiasci.com
, . D.. ,

 
EFFECTS OF NON-LAMBERTIAN BOTTOM BOUNDARIES ON UPWELLING RADIANCES
 
Non-Lambertian surfaces do not reflect light equally into all directions. Seagrass beds are an example of such a surface at the bottom of a shallow water column. Looking straight down, the sensor may view mostly a bright sand substrate with some seagrass leaves but, when looking at off-nadir angles, the sensor may view mostly seagrass leaves, which are often much darker than the substrate. Algorithms for the retrieval of bottom properties or depth often assume the bottom to be Lambertian and may become inaccurate if this assumption is not satisfied. The optical effects of non-Lambertian bottom boundaries were investigated as part of the Coastal Benthic Optical Properties (CoBOP) program, using the HYDROLIGHT radiative transfer numerical model. The effects of a non-Lambertian bottom reflectance on the upwelling radiance can be considerable for in-water sensors very near the bottom and for large off-nadir look angles. However, the effects are generally small for above-water sensors and for look angles commonly used in ocean color remote sensing.
 
Day: Tuesday, Feb. 2
Time: Poster
Location: Sweeney Center
 
Code: SS43TU0488S