LHTFL ----- The model uses a temperature-independent latent heat of evaporation, 2.5e6 J/kg. Using a density of water (1e3 kg/m**3), gives 1 w/m**2 = 1 (w/m**2) * (1/2.5e6) (kg/J) * (1/1e3) (m**3/kg) * (1000 mm/m) * (24*3600) (s/day) = (24*3600/2.5e6) mm/day = 0.03456 mm/day Multiply the LHTFL (latent heat flux, w/m**2) by 0.03456 get the evaporation in mm/day. Negative LHTFL is dew formation. bulk aerodynamic formulas based on similarity theory ref: Betts, Hong and Pan, Monthly Weather Review 1996