Similarity spectrum for turbid waters

The shape of the water leaving reflectance spectrum in the NIR wavelengths is determined largely by pure water absorption and is thus almost invariant. As such, a universal or "similarity" spectrum in the NIR is defined by normalization at 780nm. This similarity spectrum is calculated from seaborne reflectance measurements and is valid over waters ranging from moderately turbid (water-leaving reflectance at 780nm of order 10^-4 or total suspended matter concentration of order 0.3 gm^-3) to extremely turbid waters (water-leaving reflectance at 780nm of order 10^-1 or total suspended matter concentration of order 200 gm^-3). It can be downloaded here (Source: Ruddick et al., 2006).

The similarity spectrum is discussed in full detail by Ruddick et al., 2006 and can be downloaded here.

Important applications of the NIR similarity spectrum include atmospheric correction of ocean colour data over turbid waters, quality control of seaborne, airborne, and space borne reflectance measurements in turbid waters.