Filippi, A. M.. University of South Carolina, filippi@ellie.cla.sc.edu
, . M.. ,

 
INTENSIVELY LEARNING OPTICAL OCEANOGRAPHY: THE BIDIRECTIONAL REFLECTANCE DISTRIBUTION FUCTION (BRDF) EFFECT ON INVERSION ALGORITHMS FOR IOP ESTIMATION
 
The NEMO (Naval EarthMap Observer) and MODIS imaging spectrometers will feature off-nadir viewing capabilities, suggesting an impetus for investigating the effect of the bidirectional reflectance distribution function on inversion algorithms. The specific question was whether IOPs estimated from Rrs varied as a function of viewing geometry. Reflectance measurements from East Sound, WA were collected using a Spectrix spectrometer every 45 degrees azimuth (phi) from 45 to 270 degrees relative to the sun, and at 30, 45, and 60 degree viewing angles (theta) at every azimuth considered. A MODIS inversion algorithm for ([Chl a]), aph(675), and ag(400) was employed; [Chl a] was calculated from the aph(675) value. It was found that [Chl a] and the absorption coefficients did indeed vary as a function of theta and phi, and the estimated ag values were much larger than spectrophotometric measurements for 0 and 2 meter water samples. Although the estimated [Chl a] values varied, most were close to pad box measurements. In addition, similar trends in relative magnitude changes were observed in both the estimated [Chl a] and the estimated absorption coefficient values as theta and phi varied. Modeled Hydrolight Rrs and results using the Roesler-Perry spectral inversion algorithm will also be reported.
 
Day: Thursday, Feb. 4
Time: Poster
Location: Sweeney Center
 
Code: SS53TH1659S