Calculation of friction velocity over land
Over land the friction velocity u* in TM5 is calculated from the wind at 10 m. Previously, the calculation used the wrong height in one of the logarithmic scale factors (10 instead of 75 m). This bug has now been repaired.
Still, the calculation neglects the contribution from the free convection velocity scale (w*) and the stability profile functions (Psi_M). It is unclear why u* isn't calculated directly from the surface momentum stress, as is done over sea. See IFS cy31r1 documentation for details.