TAKEN FROM WG. Spectral seawater absorption and 
 scattering coefficients in units of /m.
 Derived from Smith and Baker 1981 (200-370 nm),
 and (730-800 nm), Pope and Fry 1997 (380-720)
 Circio and Petty 1951 (800nm-2.5um), and 
 and Maul 1985 (2.5-4um).  Format i5,f15.4,f10.4
  400         0.0063    0.0000
  425         0.0051    0.0000
  450         0.0083    0.0000
  475         0.0119    0.0000
  500         0.0215    0.0000
  525         0.0407    0.0000
  550         0.0550    0.0000
  575         0.0849    0.0000
  600         0.1995    0.0000
  625         0.2850    0.0000
  650         0.3512    0.0000
  675         0.4559    0.0000
  700         0.6433    0.0000