title: Calibration of SeaWiFS. II. Vicarious techniques.
abstract: We present an overview of the vicarious calibration of the Sea-Viewing Wide Field-of-view Sensor (SeaWiFS). This program has three components: the calibration of the near-infrared bands so that the atmospheric correction algorithm retrieves the optical properties of maritime aerosols in the open ocean; the calibration of the visible bands against in-water measurements from the Marine Optical Buoy (MOBY); and a calibration-verification program that uses comparisons between SeaWiFS retrievals and globally distributed in situ measurements of water-leaving radiances. This paper describes the procedures as implemented for the third reprocessing of the SeaWiFS global mission data set. The uncertainty in the near-infrared vicarious gain is 0.9%. The uncertainties in the visible-band vicarious gains are 0.3%, corresponding to uncertainties in the water-leaving radiances of approximately 3%. The means of the SeaWiFS/in situ matchup ratios for water-leaving radiances are typically within 5% of unity in Case 1 waters, while chlorophyll a ratios are within 1% of unity. SeaWiFS is the first ocean-color mission to use an extensive and ongoing prelaunch and postlaunch calibration program, and the matchup results demonstrate the benefits of a comprehensive approach.
authors: Science Applications International Corporation, Beltsville, Maryland 20705, USA.
authors: R E
authors: RE
authors: Eplee
authors: W D
authors: WD
authors: Robinson
authors: S W
authors: SW
authors: Bailey
authors: D K
authors: DK
authors: Clark
authors: P J
authors: PJ
authors: Werdell
authors: M
authors: M
authors: Wang
authors: R A
authors: RA
authors: Barnes
authors: C R
authors: CR
authors: McClain