An approximate analytical model for footprint estimation of scaler fluxes in thermally stratified atmospheric flows

An approximate analytical model was developed to estimate scalar Aux footpr int in thermally stratified atmospheric surface layer flows. The proposed m odel was based on a combination of Lagrangian stochastic dispersion model r esults and dimensional analysis. The main advantage of this model is its ab ility to analytically relate atmospheric stability, measurement height, and surface roughness length to flux and footprint. Flux estimation by the pro posed model was in good agreement with those calculated by detailed Euleria n and Lagrangian models. Measured water vapor fluxes collected along a down wind transect of a transition from a desert to an irrigated potato site wer e also used to assess the proposed model performance in the held. It was fo und that the model well reproduced the measured flux evolution with downwin d distance. (C) 2000 Elsevier Science Ltd. All rights reserved.