The Apparent Optical Properties (OC_AOP) data suite provides satellite-derived measures of the interaction between solar radiation and the upper ocean. AOPs are “apparent” because they depend not only on the inherent optical properties (IOPs) of seawater and its constituents but also on the ambient light field. These variables are critical for studying light penetration, primary productivity, and biogeochemical cycling.

Usage notes:

• Rrs and Rrs_unc are stored as scaled integers; use the scale_factor and add_offset attributes to obtain physical values.

• Quality control should use l2_flags per the flag_meanings attribute to mask clouds, land, high glint, and other conditions.

  Geophysical variables in this suite include:
  • Rrs — Remote sensing reflectance (sr⁻¹)
  • Rrs_unc — Uncertainty in remote sensing reflectance (sr⁻¹)
  • aot_865 — Aerosol optical thickness at 865 nm (unitless)
  • angstrom — Aerosol Ångström exponent, 443–865 nm (unitless)
  • avw — Apparent Visible Wavelength (nm)
  • nflh — Normalized Fluorescence Line Height (W m⁻² µm⁻¹ sr⁻¹)
  • l2_flags — Level-2 processing flags (bitmask; see per-variable attributes for flag_masks and flag_meanings)