An approximate analytical model for footprint estimation of scalar ̄uxes in thermally strati®ed atmospheric ̄ows
نویسندگان
چکیده
An approximate analytical model was developed to estimate scalar ̄ux footprint in thermally strati®ed atmospheric surface layer ̄ows. The proposed model was based on a combination of Lagrangian stochastic dispersion model results and dimensional analysis. The main advantage of this model is its ability to analytically relate atmospheric stability, measurement height, and surface roughness length to ̄ux and footprint. Flux estimation by the proposed model was in good agreement with those calculated by detailed Eulerian and Lagrangian models. Measured water vapor ̄uxes collected along a downwind transect of a transition from a desert to an irrigated potato site were also used to assess the proposed model performance in the ®eld. It was found that the model well reproduced the measured ̄ux evolution with downwind distance. Ó 2000 Elsevier Science Ltd. All rights reserved.
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