The Project for Intercomparison of Land-surface Parameterization Schemes (PILPS) has shown that different land surface models (LSMs) driven by the same meteorological forcing can produce markedly different surface energy and water budgets, even when certain critical aspects of the LSMs (vegetation cover, albedo, turbulent drag coefficient, and snowcover) are carefully controlled. To help explai...

Moisture and heat fluxes from the land surface to the atmosphere form a critical nexus between surface hydrology and atmospheric processes, particularly those relevant to precipitation. Although current theory suggests that soil moisture generally has a positive impact on subsequent precipitation, individual studies have shown support both for1–4 and against5–7 this positive feedback. Broad ass...

A dual-beam surface-layer scintillometer (SLS) was used to estimate sensible heat flux (H) every 2 min for a path length of either 50 or 101 m, for more than 30 months in a mesic grassland in eastern South Africa. The SLS method relies on Monin-Obukhov similarity theory, the correlation between the laser beam signal amplitude variances and the covariance of the logarithm of the beam signal ampl...

24 The main goal of this research was to evaluate the potential of the dual approach of 25 FAO-56 for estimating actual crop evapotranspiration (AET) and its components (crop 26 transpiration and soil evaporation) of an olive (Olea europaea L.) orchard in the semi arid 27 region of Tensift-basin (central of Morocco). Two years (2003 and 2004) of continuous 28 measurements of AET with the eddy c...

The behaviour of various formulas for évapotranspiration of grass in nonrestricted soil water conditions is considered. These are the expressions based on the Penman formula, i.e. "old" Penman, Penman-Monteith, Thorn-Oliver and the version recommended more recently by the FAO. Moreover, the Priestley-Taylor and the Makkink formulas are considered, which are radiation-based. Comparisons are made...

Estimating the magnitude of the different fluxes in the hydrological cycle is essential if we are to predict the impacts of climate change. However, climate change is acting on a dynamic three dimensional globe where change in one region may produce impacts in another. This creates a need to expand the current climate change studies to encompass the entire globe. Evaporation is a key component ...