Sensible heat flux estimates using surface renewal analysis A study case over a peach orchard

摘要

This paper reports on an experiment over a peach orchard to study the reliability of surface renewal, SR, analysis for estimating sensible heat flux. The peach orchard was located within the San Joaquin Valley near Parlier, CA, where clear skies, high summer temperatures, light winds, no rainfall and regional advection were the typical weather conditions. To account for the climate characteristics, the roughness sub-layer depth was estimated half-hourly. A model based on a mixing-length theory for momentum combined with mixing-layer analogy was derived and coupled with SR analysis. Roughness sub-layer estimates indicated that the top of the roughness sub-layer was oscillating above and below the measurement height. Accordingly, SR analysis was challenged as a method to be applied at a fixed height above the canopy top. Regardless of the atmospheric surface boundary-layer stability, sensible heat flux estimates were close to those determined by the eddy covariance method.