stresstc

 STRESSTC: computes the neutral wind stress following Smith (1988).
 tau = STRESSTC(sp,z,Ta,rhoa) computes the neutral wind stress given the 
 wind speed and air temperature at height z following Smith (1988),
 J. Geophys. Res., 93, 311-326. Air temperature and density are optional
 inputs. 

   INPUT:  sp    - wind speed   [m/s]
           z     - measurement height  [m]
           Ta    - air temperature (optional) [C]
           rhoa  - air density (optional)  [kg/m^3]

   OUTPUT: tau   - wind stress  [N/m^2]

0001 function tau=stresstc(sp,z,Ta,rhoa)
0002 % STRESSTC: computes the neutral wind stress following Smith (1988).
0003 % tau = STRESSTC(sp,z,Ta,rhoa) computes the neutral wind stress given the
0004 % wind speed and air temperature at height z following Smith (1988),
0005 % J. Geophys. Res., 93, 311-326. Air temperature and density are optional
0006 % inputs.
0007 %
0008 %   INPUT:  sp    - wind speed   [m/s]
0009 %           z     - measurement height  [m]
0010 %           Ta    - air temperature (optional) [C]
0011 %           rhoa  - air density (optional)  [kg/m^3]
0012 %
0013 %   OUTPUT: tau   - wind stress  [N/m^2]
0014 
0015 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0016 % 3/8/97: version 1.0
0017 % 8/26/98: version 1.1 (revised by RP)
0018 % 4/2/99: versin 1.2 (air density option added by AA)
0019 % 8/5/99: version 2.0
0020 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0021 
0022 % load constants
0023 as_consts;
0024 
0025 if nargin == 2,
0026   Ta   = Ta_default;
0027   rhoa = rho_air;
0028 elseif nargin == 3
0029   rhoa = rho_air; 
0030 end
0031 
0032 [cd,u10] = cdntc(sp,z,Ta);
0033 tau = rhoa*(cd.*u10.^2);
0034