SeaWiFS Solar Calibration Time Series

Image generated April 30, 2004.

This plot shows the current SeaWiFS solar calibration time series. For all of the plots, the radiances have been normalized to an Earth-Sun distance of one Astronomical Unit and the time series for each band has been normalized to the first observation in that band. The time series shows the change in the solar diffuser reflectance as a function of time. The solar diffuser is a flat metal plate with a coating of YB71 paint.

To generate this plot, the operational time corrections have been applied to the solar radiances. The time series have also been corrected for changes in the azimuthal angle of the image of the sun on the solar diffuser, although this correction is incomplete because how the BRDF of the diffuser is changing with time is not fully understood. The time-corrected solar data, prior to the application of the azimuthal angle correction, are shown here.

The noise in the time series shown above arises primarily from the partial azimuthal angle correction.

To date, calibrations have been obtained for more than 2300 days over the 6+ years of the mission.

References