The physical, biological, chemical, and optical processes of the ocean operate on a wide variety of spatial and temporal scales, from seconds to decades and from micrometers to thousands of kilometers (Dickey et al., this issue; Dickey, 1991). These processes drive the accumulation and loss of living and non-living mass constituents in the water column (e.g., nutrients, phytoplankton, detritus, sediments). These mass constituents frequently have unique optical characteristics that alter the clarity and color of the water column (e.g., Preisendorfer, 1976). This alteration of the ocean color, or more specifically the change in the spectral “water-leaving radiance,” Lw(λ), has led to the development of optical techniques to sample and study the change in biological and chemical constituents (Schofield et al., this issue). Thus, these optical techniques provide a mechanism to study the effects of underlying biogeochemical processes. In addition, because time- and space-dependent changes in Lw(λ) may be measured remotely, optical oceanography provides a way to sample ecological interactions over a wide range of spatial and temporal scales.