Some Considerations in Accounting For All The Surface Energy Balance Components in Forest, Agricultural and Grassland Ecosystems

The components of the surface energy budget consists of both kinematic terms (sensible and latent heat fluxes), up- and downwelling short and longwave radiation, and conductive heat fluxes associated with warming/cooling surfaces in the lowest part of the boundary layer. Quantification of the turbulent fluxes and the associated corrections to these fluxes have been extensively documented and described over the past 30 years. However, the conductive heat fluxes and associated storage terms, which are often assumed to be negligible, in some cases turn out to be a significant component of the surface energy budget. When determining these conductive and storage fluxes, especially the soil heat flux, physical characteristics and properties are necessary in the quantification of these fluxes, including biomass, plant water content, soil moisture, and woody biomass. This includes parameters such as volumetric heat capacity and thermal conductivity, which for soils is highly dependent on the volumetric water content. Data from three land use types (forest, agricultural, grassland) will be used to demonstrate when these conductive fluxes are important and what types of ancillary data are needed in order to properly characterize the magnitude of these fluxes