m 
ON ANGULAR DISTRIBUTION OF RADIATION 
REFLECTED FROM RUFFLED SEA 
by 
H. ARST 
Tallinn, Institute of Thermophysics and Electrophysics 
Academy of Sciences of The Estonian S.S.R. 
A mathematical model has been developed for describing the 
angular distribution of monochromatic electromagnetic radiation 
reflected from the ruffled sea surface with and without oil 
film covering the water. The model works both in case of an 
incident parallel beam radiation as well as in case of the dif- 
fuse and direct solar radiation. The reflected radiance is con- 
sidered a kind of weighted average value, the probability of 
reflection from a given solid angle being a weicht ratio. The 
reflecting wave surface is described by the probability distri- 
bution law of the normals of surface elements. The reflectivity 
of the sea water is calculated in view of the possibility of a 
thin oil film on the sea surface. 
The given model is realized as a program for a computer. 
The initial data are: I) wavelength of incident radiation; 2) 
solar zenith anole and azimute; 3) zenith angle of observation 
(the azimuth of observation is considered to be zero); 4) 
thickness of oil film; 5) optic constants of water and oil; 6) 
downwelling irradiance on the sea surface; 7) wind velocity and 
direction. The single run results of the proaram are the values 
of the upwelling radiation apart from reflected sky radiation 
and the sun glitter on calm as well as ruffled sea with and with- 
out oil film covering. 
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