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Remote sensing applications in Oceanography: How much we can see using ocean color?. Martin A Montes Ph.D Rutgers University Institute of Marine and Coastal Sciences. Spring 2008. Main topics. Introduction: definitions, sensor characteristics Model development:
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Remote sensing applications in Oceanography: How much we can see using ocean color? Martin A Montes Ph.D Rutgers University Institute of Marine and Coastal Sciences Spring 2008
Main topics Introduction: definitions, sensor characteristics Model development: IOP’s, AOP’s, Forward and Inversion approach Applications: chl, phytoplankton size structure
Ocean color sensors Definition: Types: Passive vs Active Sensor characteristics: swath, footprint, revisiting time, spectral resolution
First sensors: B& W Ocean color sensors: characteristics • Spectral resolution: • number of channels?, bandwidth? • Temporal resolution: • revisiting time?
Ocean color sensors: characteristics http://www.ioccg.org/reports/
Ocean color sensors: characteristics http://www.ioccg.org/reports/
Ideally we need to match channels and optical signatures Ocean color sensors: characteristics SIO PIER
Lidar and detection of plankton and fish layers Spatial Variability in Spatial Variability in Biological Standing Stocks and SST across the GOA Basin and Shelves 2003. Evelyn Brown, Martin Montes, James Churnside. AFSC Symposium
Model development Inherent and apparent Optical properties IOP’S and biogeochemical parameters Forward vs Inversion models
IOP’s:not influenced by the light field (e.g., a, b, c coefficients) Inherent and Apparent Optical properties IOP’s: influenced by the light field (e.g., Rrs, Kd)
IOP’S & biogeochemical parameters VSF?? Absorption Backscattering Phytoplankton CDOM POC SPM
Forward vs Inversion models Inversion: Rrs Forward: IOP’s Rrs IOP’s (Empirical, analytical, statistical) (Hydrolight or non-commercial code)
Forward: Monte Carlo simulations Forward vs Inversion models Montes-Hugo et al. 2006, SPIE
Applications Chlorophyll a concentration in case II waters of Alaska Phytoplankton size structure in Antarctic waters
Rrs: Seawifs, MODIS, Microsas, • hand-held spectrometer • bb = HydroScat • Empirical: band ratio vs • spectral curvature Chlorophyll a concentration in case II waters of Alaska Montes-Hugo et al. 2005. RSE
Remote sensing reflectance TOA 200 m height Spectral curvature Validation RMSlog10 = 0.41 RMSlog10 = 0.33 No regression
STAY AWAY FROM CDOM USING LONGER WAVELENGTHS!!
Spectral Backscattering approach • bb from HS-6 • Rrs from PRR, SeaWiFS • Phytoplankton size: chl fractions , HPLC Phytoplankton size structure in Antarctic waters bbx () = M (o/) bbx Montes-Hugo et al. 2007. IJRS
PRR Field data Phytoplankton size structure in Antarctic waters