Translator Disclaimer
Paper
8 September 2015 Geometric effects in SeaWiFS lunar observations
Author Affiliations +
Abstract
The radiometric stability requirements for ocean color climate data records place tight constraints on the onorbit calibration of ocean color instruments. A major component of the on-orbit calibration methodology for NASA ocean color sensors is the normalization of lunar observations for variations in observing geometry by the USGS ROLO photometric model of the Moon. SeaWiFS made 204 lunar observations over its 13-year mission. 145 radiometric trending observations were made at low phase angles (-8° to -6° and +5° to +10°). 59 additional observations were made at high phase angles (-49° to -27° and +27° to +66° degrees). The NASA Ocean Biology Processing Group has undertaken a reanalysis of residual geometric effects in the SeaWiFS lunar observations. Ratios of SeaWiFS observations to ROLO model predictions were fit with quadratic functions of phase angle and linear functions of sub-spacecraft point and sub-solar point libration longitude and latitude angles. The resulting phase and libration fit coefficients have been used as additional geometric corrections for the SeaWiFS lunar observations. For the low phase angle observations, the phase corrections are 0.16% and the libration corrections are 0.18%. For the low and high phase angle observations, the phase corrections are 1.8% and the libration corrections are 0.22%. These geometric corrections have reduced the overall scatter in the lunar observations, bringing the high phase angle data into family with the low phase angle measurements without impacting the radiometric response in the low phase angle observations.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Robert E. Eplee Jr., Frederick S. Patt, and Gerhard Meister "Geometric effects in SeaWiFS lunar observations", Proc. SPIE 9607, Earth Observing Systems XX, 960704 (8 September 2015); https://doi.org/10.1117/12.2185939
PROCEEDINGS
14 PAGES


SHARE
Advertisement
Advertisement
RELATED CONTENT

Impacts of climate change on peanut yield in China simulated...
Proceedings of SPIE (September 01 2017)
Climate change and sounder radiometric stability
Proceedings of SPIE (August 12 2009)
Report on the NIST workshop of December 10, 2009 ...
Proceedings of SPIE (August 12 2010)
EOS-AM1: L-2
Proceedings of SPIE (January 27 1997)
Use of the Moon as a reference for satellite based...
Proceedings of SPIE (November 04 2004)

Back to Top