- Jerlov water type: an integer value from 1 to 5.
- option =
- routine = mod_mixing.F
- keyword = WTYPE
- input = roms.in
This parameter selects amongst a set of coefficients that define the double exponential profile for shortwave radiation absorption calculated by Paulson and Simpson's (1977) fit to the data of Jerlov (1976).
WTYPE (roms.in) values 1 through 5 correspond to Jerlov's classification of water types I, IA, IB, II and III, respectively.
The model for the downward flux of solar radiation is:
where is the downward shortwave radiation at the sea surface. This parameterization is implemented in lmd_swfrac.F if called for. Downward shortwave data (or an analytical value) is required as input.
The parameters of this simple optical model are described and set in mod_scalars.F in the block headed "Water clarity parameters":
lmd_mu1 Reciprocal of the absorption coefficient for solar wavelength band 1 as a function of the Jerlov water type. Units are meters. lmd_mu2 Reciprocal of the absorption coefficient for solar wavelength band 2 as a function of the Jerlov water type. Units are meters. lmd_r1 Fraction of total radiance for wavelength band 1 as a function of the Jerlov water type.
The values are: