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OBPG Status Report. Chuck McClain & Gene Feldman Ocean Biology Processing Group Leaders NASA Carbon Cycle & Ecosystems Joint Science Team Meeting Ocean Breakout Session May 1, 2008. OBPG Data Set & Mission Support Activities. SeaWiFS MODIS/Aqua: Ocean Color & SST*
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OBPG Status Report Chuck McClain & Gene Feldman Ocean Biology Processing Group Leaders NASA Carbon Cycle & Ecosystems Joint Science Team Meeting Ocean Breakout Session May 1, 2008
OBPG Data Set & Mission Support Activities • SeaWiFS • MODIS/Aqua: Ocean Color & SST* • MODIS/Terra: Ocean Color & SST* • NPP/VIIRS: Ocean Color & SST • Sensor & EDR algorithm performance • Launch in 2010 • Aquarius (data system): Launch in 2010 • Historical data • CZCS • OCTS • Sensor & mission concept development • Ocean Radiometer for Carbon Assessment (ORCA) • Aerosols, Clouds, Ecology (ACE) *Primarily data processing & distribution
SeaWiFS • Internal telemetry anomaly on Spacecraft on Dec. 31, 2007 • Resulted in loss of GPS and attitude data in downlinked data stream. • SeaWiFS instrument unaffected • Data could not be processed • GeoEYE recovery plan • Switch to the B-side computer: imaging on March 11 for 1 day. • Spurious GPS position caused the spacecraft safehold. • Return to "nominal" imaging operations was restored on April 4 and continues. • Current status • The GPS receiver has intermittent autonomous resets • Results in time shifts in the data stream & navigation failures • Approximately 30% of the GAC orbits affected • Discussions underway with GeoEye to identify source of problem • Option for 1 year of GAC exercised on April 12. • The NOAA data buy for HRPT coverage of U.S. coastal waters not being renewed. • Orbit drift impacting calibration (presumably thermal sensitivity) • Effects evident in lunar calibration
Reprocessing: Primary Improvements • CZCS, OCTS, SeaWiFS, MODIS (Terra & Aqua) • Revise band centers & related algorithms • E.g., MODIS 551 nm band center to 547 nm • Switch to K(490) based on Morel or Lee • Update aerosol models based on AERONET analyses • NO2 corrections using global NO2 satellite products • MODIS/Terra • Updated on-board calibration • SeaWiFS-based vicarious calibration of polarization & RVS • Franz presentation later provides details • MODIS/Aqua • Updated on-board calibration • SeaWiFS • Revised prelaunch and lunar calibrations • Expand glint and straylight masks • Update PAR and calcite algorithms Candidate new products: POC (Stramski) PAR (Frouin): MODIS Lwn(678): MODIS FLH: MODIS Euphotic depth (Lee) Kpar (Morel)
OBPG Refereed Publications • Eplee, R. E., F. S. Patt, R. A. Barnes, and C. R. McClain, SeaWiFS long-term solar diffuser reflectance and sensor signal-to-noise analyses, Appl. Opt., 46(5), 762-773, 2007. • Franz, B. A., S. W. Bailey, P. J. Werdell, and C. R. McClain, Sensor-independent approach to the vicarious calibration of satellite ocean color radiometry, Appl. Opt., 46(22), 5068-5082, 2007. • Ahmad, Z., C. R. McClain, J. R. Herman, B. A. Franz, E. J. Kwaitkowska, W. D. Robinson, E. J. Bucsela, and M. Tzortziou, Atmospheric correction of NO2 in retrieving water-leaving reflectances from the SeaWiFS and MODIS measurements, Appl. Opt., 46(26), 6504-6512, 2007. • Werdell, P. J., S. W. Bailey, B. A. Franz, A. Morel, C. R. McClain, and S. B. Hooker, The on-orbit vicarious calibration of ocean color sensors using a sea surface reflectance model, Appl. Opt., 46(23), 5649-5666, 2007. • Eplee, R. E., Jr., F. S. Patt, B. A. Franz, S. W. Bailey, G. Meister, C. R. McClain, SeaWiFS on-orbit gain and detector calibrations: impact on ocean products, Appl. Opt., 46(27). 6733-6750, 2007. • Gordon, H. R., B. A. Franz, Remote sensing of ocean color: Assessment of the water-leaving radiance bidirectional effects on the atmospheric diffuse transmittance for SeaWiFS and MODIS intercomparisons, Remote Sens. Environ., 112, 2677-2685, 2008. • Bailey, S. W., S. B. Hooker, D. Antoine, B. A. Franz, and P. J. Werdell, Sources and assumptions for the vicarious calibration of ocean color satellite observations, Appl. Opt. 47, 2035-2045, 2008. • Franz, B. A., E. J. Kwiatkowska, G. Meister, and C. R. McClain, Moderate Resolution Imaging Spectroradiometer on Terra: Limitations for Ocean Color Applications, J. Appl. Remote Sens., in press.