SKCT. 4 J LIGHT 449 



s Scattering coefficient 



•sl^, ± ) Scattering coefficient for up ( + ) and clown ( — ) streams of flux 



a Volume scattering function 



o(d) Volume scattering function 



o(p, 6. (j). 6', (f)') Volume scattering function at point p observed in direction ^, ^ ; irradiated 



from direction 9', cf)' 



f Forward scattering coefficient 



f(Z, ± ) Forward scattering coefficient for up ( + ) and down ( — ) streams of flux 



b Backward scattering coefficient 



b(Z, ± ) Backward scattering coefficient for up ( + ) and down ( — ) streams of flux 



K Diffuse attenuation function 



K{Z, + ) Diffuse attenuation function for upwelling irradiance 



K{Z, — ) Diffuse attenuation function for downwelling irradiance 



k(Z, + ) Diffuse attenuation function for upwelling scalar irradiance 



k[Z, — ) Diffuse attenuation function for downwelling scalar irradiance 



A'oo Limit of k{Z, + ) as Z ^> oo 



D{Z, + ) Distribution function for upwelling stream 



D(Z, — ) Distribution function for downwelling stream 



D( + ) Limit of D{Z, + ) as Z ^ oc 



D{-) Limit of Z>(Z,-) as Z-> 00 



H(Z, + ) Reflectance function for upwelling stream 



B(Z, — ) Reflectance function for downwelling stream 



7?oo Limit of R{Z, + ) as Z -^ x 



Jq Initial intensity 



Iz Intensity at depth Z 



Z Depth 



dZ Depth differential 



r Radius of a sphere 



r Path length 



;■' Path length different from r 



1(6) Path length 



6 Angle froni forward beam of nephelometer 



6 Angle from zenith 



d' Angle from zenith 



(j) Azimuth angle 



<f>' Azimuth angle 



Q Solid angle 



^r Specific solid angle 



dQ(d', (j)') Specific solid angle differential 



Aoj Solid angle (small) 



da> Solid angle differential 



A Area 



A{d) Projected area 



S Source 



G Gershun tube 



Jg Radiant iiit(Misity of a beam at an angle d fi'om the normal. 



References 



Atkins, W. R. 0., C!. L. Clarke, H. Pettersson, H. H. Poole, C. L. Utterback and A. 



Angstrom, 1938. Measurement of submarine daylight. J . Cons. Explor. Mer, 13, 37-57. 

 Austin, R. W'., 1959. \\'ater clarity meter, operating and maintenance instructions. 



S.I.O. Ref. Xo. 59-9. Available : L".S. Dej)t. of Commerce, Office of Technical Services 



Rpt. No. 147597, 109 pp. 



