Heat transfer to and from vegetated surfaces: An analytical method for the bulk exchange coefficients

Abstract

The semi-analytical model outlined in a previous study (Massman, 1987) to describe momentum exchange between the atmosphere and vegetated surfaces is extended to include the exchange of heat. The methods employed are based on one-dimensional turbulent diffusivities and use analytical solutions to the steady-state diffusion equation. The model is used to assess the influence that (1) the canopy foliage structure and density, (2) the wind profile structure within the canopy, and (3) the shelter factor can have upon the inverse surface Stanton number (kB −1) as well as to explore the consequences of introducing a scalar displacement height which can be different from the momentum displacement height. In general, the triangular foliage area density function gives results which agree more closely to observations than that for constant foliage area density. The intended application of this work and its predecessor (Massman, 1987) is for parameterizing the bulk aerodynamic resistances for heat and momentum exchange for use within large-scale models of plant-atmosphere exchanges.