


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]

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;