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spshfttc

PURPOSE ^

SPSHFTTC: adjusts wind speed from z1 to z2 following Smith (1988).

SYNOPSIS ^

function [sp2,ustar]=spshfttc(sp1,z1,z2,Ta)

DESCRIPTION ^

 SPSHFTTC: adjusts wind speed from z1 to z2 following Smith (1988).
 sp2 = SPSHFTTC(sp1,z1,z2,Ta) shifts the wind speed sp1 measured at z1 to
 z2 using the neutral drag coefficient given the wind speed and air
 temperature at height z following Smith (1988), J. Geophys. Res., 93,
 311-326. Assumes z1 and z2 scalars. Ta may be a constant. 

   INPUT:  sp1 - measured wind speed [m/s]
           z1 - measurement height [m]
           z2 - desired height [m]
           Ta - air temperature ([C] (optional)

   OUTPUT: sp2 - predicted wind speed [m/s]
           ustar - fiction velocity  [m/s]

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

0001 function [sp2,ustar]=spshfttc(sp1,z1,z2,Ta)
0002 % SPSHFTTC: adjusts wind speed from z1 to z2 following Smith (1988).
0003 % sp2 = SPSHFTTC(sp1,z1,z2,Ta) shifts the wind speed sp1 measured at z1 to
0004 % z2 using the neutral drag coefficient given the wind speed and air
0005 % temperature at height z following Smith (1988), J. Geophys. Res., 93,
0006 % 311-326. Assumes z1 and z2 scalars. Ta may be a constant.
0007 %
0008 %   INPUT:  sp1 - measured wind speed [m/s]
0009 %           z1 - measurement height [m]
0010 %           z2 - desired height [m]
0011 %           Ta - air temperature ([C] (optional)
0012 %
0013 %   OUTPUT: sp2 - predicted wind speed [m/s]
0014 %           ustar - fiction velocity  [m/s]
0015 
0016 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0017 % 3/8/97: version 1.0
0018 % 8/27/98: version 1.1 (revised to use CDNTC efficiently by RP)
0019 % 8/5/99: version 2.0
0020 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
0021 
0022 % set constants
0023 as_consts;
0024 
0025 if nargin==3,
0026   Ta=Ta_default;
0027 end;
0028 
0029 % find cd and ustar
0030 [cd,sp10]=cdntc(sp1,z1,Ta);
0031 
0032 ustar=sqrt(cd).*sp10;
0033 
0034 sp2=sp10+ustar.*log(z2./10)/kappa;

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