The Closed-Loop Ocean Simulation for Evaluation of ocean color retrieval algorithms (CLOSE) Level-2 collection provides swath-based ocean-color products retrieved from the simulated CLOSE Level-1B observations. Geophysical variables include hyperspectral remote sensing reflectance, chlorophyll-a concentration, diffuse attenuation coefficients, aerosol optical properties, and Generalized Inherent Optical Property (GIOP) model-derived absorption and backscattering properties. The products support direct comparison with the corresponding model inputs for evaluation of atmospheric correction, bio-optical retrieval accuracy, error propagation, and algorithm uncertainty.

Geophysical variables in this suite include:

• Rrs — Remote sensing reflectance (sr⁻¹)
• chlor_a — Chlorophyll-a concentration from the OCI algorithm (mg m⁻³)
• Kd — Diffuse attenuation coefficients from the Lee algorithm (m⁻¹)
• a — Total absorption from the GIOP model (m⁻¹)
• adg — Absorption due to colored dissolved and detrital material from the GIOP model (m⁻¹)
• aph — Phytoplankton absorption from the GIOP model (m⁻¹)
• bb — Total backscattering from the GIOP model (m⁻¹)
• bbp — Particulate backscattering from the GIOP model (m⁻¹)
• angstrom — Aerosol Ångström exponent from 443 to 865 nm
• aot_865 — Aerosol optical thickness at 865 nm
• l2_flags — Level-2 processing flags