PACE OCI-derived Inherent Optical Properties (IOPs) help us understand how different wavelengths (colors) of light are scattered and absorbed by materials present in natural waters such as lakes, coastal waters, and the ocean. The different constituents in natural waters - including the water itself, phytoplankton, dissolved matter, and non-algal particulate matter - absorb and scatter light in different ways due to factors such as shape, size, and pigmentation. Consequently, the types and relative concentrations of constituent matter drive the character of the light reflected from the water.
The following IOP parameters are currently being validated using PACE hyperspectral OCI data:
- Hyperspectral backscattering coefficient (bb)
- Hyperspectral particulate backscattering coefficient (bbp)
- Phytoplankton absorption coefficient (aph)
- Non-algal particle plus dissolved organic matter absorption coefficient (adg)
- Non-water absorption coefficient (anw)
Validation measurements at the sea surface have been individually quality controlled according to the latest protocols from the IOCCG Ocean Optics & Biogeochemistry Protocols for Satellite Ocean Colour Sensor Validation. IOP data product validation involves extracting satellite measurements and comparing ("matching") them with corresponding field measurements based on temporal and spatial proximity. Matched pairs are quality controlled based on criteria described in Bailey and Werdell (2006) and in the SeaBASS validation protocols.