Investigating an Instrument for Measurement of Hyperspectral Backscattering in Natural Waters

The remote sensing reflectance signal measured by an ocean color satellite is to first order proportional to the ratio of backscattered to absorbed light. Therefore in situ measurements of absorption and backscattering, as functions of wavelength, along with in situ and satellite radiometery, are key to refinement and calibration of legacy ocean color algorithms, as well as development of next generation ocean color products such as phytoplankton functional type. Currently, commercial instruments exist for in situ measurement of the hyperspectral absorption coefficient, but no instrument exists for measurement of the hyperspectral backscattering coefficient. We propose to develop an active sensor for in situ measurement of the hyperspectral backscattering coefficient. We are considering a design based on a broadband white source (chopped), monochromator for varying the source beam wavelength, and hyperspectral detectors (receiving at 2-3 angles) using spectrometers that track the monochromator. There are several configurations of the source, monochromator, spectrometer, and detector that can be considered the aim of the proposed work is to simulate a number of instrument configurations and assess technical and commercial feasibility of such hyperspectral backscattering instrument. The proposed instrument addresses a critical gap in the field of currently available systems for measuring hyperspectral IOPs in situ, in support of hyperspectral ocean color missions.