PACE Observatory validation plan, data sources, and results

The success of Earth Science space-borne missions relies on the availability of optical field measurements, as well as a solid validation plan to assess and verify the in-orbit quality of the data products. Since the late 1990s, NASA’s SeaBASS has served the ocean color community as the primary repository for in situ radiometric and pigment observations, facilitating robust product validation across multiple missions. The PACE science data validation program is responsible for making sure data products meet mission-specified requirements and for assessing uncertainties across various water types, cloud conditions, and aerosol distributions. In addition to SeaBASS, the PACE validation plan includes 24 PACE Validation Science Teams and a targeted field campaign called PACE-PAX. Nonetheless, an ongoing challenge remains the limited number of matchups between in situ and satellite measurements due to cloud cover, data quality issues, and other constraints. Here, we discuss the limitations and challenges of ocean color validation and present the current PACE validation plan, data sources, and early validation results.