Collection and corrections of oblique multiangle hyperspectral bidirectional reflectance imagery of the water surface

• Published in: Remote Sensing of the Ocean, Sea Ice, Coastal Waters, and Large Water Regions 2017
• Main Authors: Bostater, Charles Roger, Oney, Taylor S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2017
• Subjects: Sea ice
• Online Access: http://hdl.handle.net/11141/2435; https://doi.org/10.1117/12.2277088

Fixed platform sensing, Georeferenced imagery, Geospatial mapping application, Hyperspectral remote sensing, Image rectification, Multispectral imagery, Oblique imagery, Remote sensing, Satellite imagery, Shallow subsurface sensing, Water quality, Biological materials, Chemicals removal (water treatment), Fixed platforms, Hydrophilicity Offshore oil wells, Pixels, Reflection, Remote sensing, Rock mechanics, Sea ice, Spectroscopy, Water quality Hyperspectral images of coastal waters in urbanized regions were collected from fixed platform locations. Surf zone imagery, images of shallow bays, lagoons and coastal waters are processed to produce bidirectional reflectance factor (BRF) signatures corrected for changing viewing angles. Angular changes as a function of pixel location within a scene are used to estimate changes in pixel size and ground sampling areas. Diffuse calibration targets collected simultaneously from within the image scene provides the necessary information for calculating BRF signatures of the water surface and shorelines. Automated scanning using a pushbroom hyperspectral sensor allows imagery to be collected on the order of one minute or less for different regions of interest. Imagery is then rectified and georeferenced using ground control points within nadir viewing multispectral imagery via image to image registration techniques. This paper demonstrates the above as well as presenting how spectra can be extracted along different directions in the imagery. The extraction of BRF spectra along track lines allows the application of derivative reflectance spectroscopy for estimating chlorophyll-a, dissolved organic matter and suspended matter concentrations at or near the water surface. Imagery is presented demonstrating the techniques to identify subsurface features and targets within the littoral and surf zones.