omegalmc

 OMEGALMC: estimates wind log profile correction due to surface waves.
 y=OMEGALMC(x) computes the log profile correction function due to wind
 distortion associated with surface waves. Input is x=za/Hw, where za
 is the measurement height and Hw is the dominant surface wave height. 
 Functional form is simplified (analytic) version of empirical omega
 curves shown in Fig. 9b of Large, Morzel, and Crawford (1995), J. Phys.
 Oceanog., 25, 2959-2971, with the wave-induced roughness length xr=0.15. 
 Assumes x is a vector with all elements greater than zr.

0001 function y=omegalmc(x)
0002 % OMEGALMC: estimates wind log profile correction due to surface waves.
0003 % y=OMEGALMC(x) computes the log profile correction function due to wind
0004 % distortion associated with surface waves. Input is x=za/Hw, where za
0005 % is the measurement height and Hw is the dominant surface wave height.
0006 % Functional form is simplified (analytic) version of empirical omega
0007 % curves shown in Fig. 9b of Large, Morzel, and Crawford (1995), J. Phys.
0008 % Oceanog., 25, 2959-2971, with the wave-induced roughness length xr=0.15.
0009 % Assumes x is a vector with all elements greater than zr.
0010 
0011 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0012 % 3/8/97: version 1.0
0013 % 8/5/99: version 2.0
0014 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0015 
0016 xr=0.15;
0017 ylimit=-6;
0018 y=ylimit.*ones(size(x));
0019 i=find(x<3.2967);
0020 % polynomial fit
0021 a=-2.6;
0022 p1=-0.0199;
0023 p2=0.0144;
0024 p3=0.7660;
0025 p4=0.0654;
0026 x2=x(i).^2;x3=x2.*x(i);
0027 y(i)=a.*log(x(i)./xr)+p1.*x3+p2.*x2+p3.*x(i)+p4;
0028 
0029   
0030