Difference between revisions of "Jwtype"

From WikiROMS
Jump to navigationJump to search
Line 3: Line 3:


----
----
 
<wikitex>
This parameter selects amongst a set of coefficients that define the double exponential profile for shortwave radiation absorption calculated by Paulson and Simpson's ([[Bibliography#PaulsonCA_1977a|1977]]) fit to the data of Jerlov (1976).
This parameter selects amongst a set of coefficients that define the double exponential profile for shortwave radiation absorption calculated by Paulson and Simpson's ([[Bibliography#PaulsonCA_1977a|1977]]) fit to the data of Jerlov (1976).


Line 10: Line 10:
The model for the downward flux of solar radiation is:
The model for the downward flux of solar radiation is:


  <math>Q_{down}(z) = Q_{sw}( r \, \exp(z/\mu_1) + (1-r) \, \exp(z/\mu_2) ) </math>
<div class="box">$$Q_{down}(z) = Q_{sw}( r \, \exp(z/\mu_1) + (1-r) \, \exp(z/\mu_2) )$$</div>


where ''Q_sw'' 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.  
where $Q_sw$ 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":
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
     [[Variables#lmd_mu1|lmd_mu1]]     Reciprocal of the absorption coefficient for solar
                 wavelength band 1 as a function of the Jerlov
                 wavelength band 1 as a function of the Jerlov
                 water type. Units are meters.
                 water type. Units are meters.
     lmd_mu2    Reciprocal of the absorption coefficient for solar
     [[Variables#lmd_mu2|lmd_mu2]]     Reciprocal of the absorption coefficient for solar
                 wavelength band 2 as a function of the Jerlov
                 wavelength band 2 as a function of the Jerlov
                 water type. Units are meters.
                 water type. Units are meters.
     lmd_r1      Fraction of total radiance for wavelength band 1 as
     [[Variables#lmd_r1|lmd_r1]]     Fraction of total radiance for wavelength band 1 as
                 a function of the Jerlov water type.
                 a function of the Jerlov water type.


The values are:
The values are:


     WTYPE                1      2        3      4      5
     [[Variables#Jwtype|WTYPE]]               1      2        3      4      5
     Jerlov water type :  I      IA      IB      II      III
     Jerlov water type :  I      IA      IB      II      III
      
     &nbsp;
       lmd_mu1          0.35 ,  0.6  ,  1.0  ,  1.5  ,  1.4   
       [[Variables#lmd_mu1|lmd_mu1]]           0.35 ,  0.6  ,  1.0  ,  1.5  ,  1.4   
       lmd_mu2          23.0  , 20.0  , 17.0  , 14.0  ,  7.9   
       [[Variables#lmd_mu2|lmd_mu2]]         23.0  , 20.0  , 17.0  , 14.0  ,  7.9   
       lmd_r1            0.58 ,  0.62 ,  0.67 ,  0.77 ,  0.78
       [[Variables#lmd_r1|lmd_r1]]           0.58 ,  0.62 ,  0.67 ,  0.77 ,  0.78
</wikitex>

Revision as of 16:58, 12 January 2010

Jwtype
Jwtype
Jerlov water type: an integer value from 1 to 5.
option =
routine = mod_mixing.F
keyword = WTYPE
input = roms.in

<wikitex> 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 (ocean.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:

$$Q_{down}(z) = Q_{sw}( r \, \exp(z/\mu_1) + (1-r) \, \exp(z/\mu_2) )$$

where $Q_sw$ 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:

    WTYPE                1       2        3       4       5
    Jerlov water type :  I       IA      IB      II      III
    
     lmd_mu1           0.35 ,  0.6  ,  1.0  ,  1.5  ,  1.4  
     lmd_mu2          23.0  , 20.0  , 17.0  , 14.0  ,  7.9  
     lmd_r1            0.58 ,  0.62 ,  0.67 ,  0.77 ,  0.78

</wikitex>