Calibration of SeaWiFS. II. Vicarious techniques.

Area of Science:

• Oceanography
• Remote Sensing
• Atmospheric Science

Background:

• The Sea-Viewing Wide Field-of-view Sensor (SeaWiFS) is crucial for monitoring ocean color.
• Accurate calibration is essential for retrieving meaningful oceanographic data.

Purpose of the Study:

• To present the vicarious calibration overview for the SeaWiFS mission.
• To detail the procedures for the third reprocessing of SeaWiFS global mission data.

Main Methods:

• Vicarious calibration of near-infrared bands for maritime aerosol retrieval.
• Calibration of visible bands using Marine Optical Buoy (MOBY) in-water measurements.
• Calibration-verification via comparisons with global in situ water-leaving radiance measurements.

Main Results:

• Uncertainty in near-infrared vicarious gain is 0.9%.
• Uncertainties in visible-band vicarious gains are 0.3%, leading to ~3% uncertainty in water-leaving radiances.
• SeaWiFS/in situ matchup ratios for water-leaving radiances are within 5% of unity in Case 1 waters; chlorophyll a ratios are within 1%.

Conclusions:

• SeaWiFS employed an extensive prelaunch and postlaunch calibration program.
• The comprehensive calibration approach yielded significant benefits, ensuring data quality for ocean color studies.