Optimization of a Semi-Optimization of a Semi-analytical Ocean Color analytical Ocean Color

Algorithm for Algorithm for Optically-Complex (Case II)Optically-Complex (Case II)

WatersWatersTihomir Kostadinov11.03.2003 15:17

Geog 200B, Dr. ClarkeUCSB

Structure of TalkStructure of Talk

• Introduction to Ocean Color Remote Sensing

• What are Case II waters?

• Why we care

• The GSM Semi-Analytical Algorithm

• Local Tuning

http://www.gamonline.com/catalog/colortheory/spectrum.gif

What is Ocean Color?

SeaWiFS Daily Coverage

http://seawifs.gsfc.nasa.gov/SEAWIFS/SEASTAR/seawifs_daily_coverage.mpeg

What are Case II Ocean Waters?

Based on the relative contribution of each of three components to an optical property, for example a(440nm).This criterion is wavelength dependent.

Excludes pure water contribution in classification.

Bottom effect can have influence in optically shallow waters.

Optical Property

Phytoplankton(P)

Yellow Substances(Y)

Suspended Materials(S)

Why do we care?Why do we care?

Toole and Siegel 2001Toole and Siegel 2001

•1996-1999 (N = 251) •Outliers indicate Sediments•Mean and Std curves are not similar in shape, therefore•Constituents’ concentrations vary independently.

The GSM Semi-Analytical ModelThe GSM Semi-Analytical Model

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Local TuningLocal Tuning

Acknowledgements & ReferencesAcknowledgements & References

• NASA • UCSB • Dr. David Siegel, ICESS, UCSB

• Gordon, H. R., O. B. Brown, R. H. Evans, J. W. Brown, R. C. Smith, K. S. Baker, and D. K. Clark, “A semianalytic radiance model of ocean color,” J. Geophys. Res. 93 D9, 10909–10924. 1988.

• Maritorena, S., D. Siegel, A. Peterson. "Optimization of a semi-analytical ocean color model for global-scale applications,” Applied Optics 41.15 (2002): 2705-2714.

• "Remote Sensing of Ocean Colour in Coastal and Other Optically-Complex Waters." Reports of the International Ocean-Colour Coordinating Group Ed. Sathyendranath, Shubha 2000.

• Toole, Dierdre A. and Siegel, David A. . "Modes and mechanisms of ocean color variability in the Santa Barbara Channel." Journal of Geophysical Research 160.C11 (2001): 26985-27000.