Mazel, C. H.. Physical Sciences Inc., mazel@psicorp.com
Fux, E. H.. Massachusetts Institute of Technology, eran@mit.edu
Mobley, C. D.. Sequoia Scientific Inc., mobley@sequoiasci.com

 
THE COLOR OF CORALS: CONTRIBUTION OF FLUORESCENCE AND ITS VARIABILITY WITH INCIDENT IRRADIANCE
 
We investigate the contribution of fluorescent pigments in coral host tissues to the appearance of these corals under varying conditions of ambient illumination. When fluorescence is present the optical signal reaching a detector -- whether the eye of a human observer, the film in a camera, or the electronic detector of a remote sensing system -- will be a combination of light that has been reflected from the surface without change of wavelength and light that has been absorbed at one wavelength and re-emitted at a longer wavelength. The relative contributions of these two sources to the spectral signature will depend on the incident spectral irradiance, the reflectance spectrum, and the fluorescence excitation and emission properties. Incident irradiance at the seafloor may vary due to depth, solar elevation, time of day, cloud cover, and inherent optical properties of the overlying water column. We apply a mathematical model using simulated irradiance spectra and measured coral reflectance and fluorescence characteristics to determine the extent of change in spectral signature, and hence of appearance, of fluorescent corals as a function of changes in ambient illumination.
 
Day: Thursday, Feb. 4
Time: Poster
Location: Sweeney Center
 
Code: CS61TH0502S