ON THE BRUTSAERT TEMPERATURE ROUGHNESS LENGTH MODEL FOR SENSIBLE HEAT-FLUX ESTIMATION

The scalar roughness length for temperature, z(0h), is necessary to es timate the sensible flux from atmospheric surface layer similarity the ory in conjunction with skin temperature measurements. A theoretical r elationship for z(0h) as a function of the roughness Reynolds number z (0+) which was developed by Brutsaert [1975] for rough-bluff surfaces is often used to link infrared skin temperature measurements to atmosp heric temperature measurements. Measurements of sensible heat flux and temperature at two semiarid sites are used to evaluate and test the t emperature roughness length model coefficients. Consideration of the m easurement error is important to derive an accurate set of coefficient s. These new field-based coefficients correct for some of the underpre diction of sensible heat flux at high flux rates that occurred with pa st formulations.