2016/11/05 by Pierre Gentine, P. Gentine, A. Chhang +4 · 82 citations
Earth and Planetary Sciences · Environmental Science · #Atmospheric sciences #Boundary layer #Eddy covariance #Environmental science #Evaporation #Evaporative cooler #Evapotranspiration #Geography #Geology #Humidity #Latent heat #Mechanics #Meteorological Phenomena and Simulations #Meteorology #Moisture #Planetary boundary layer #Plant Water Relations and Carbon Dynamics #Sensible heat #Turbulence #Urban Heat Island Mitigation
paper · pdf · doi:10.1002/2016gl070819
published in Geophysical Research Letters 43(22) (American Geophysical Union)
openalex publication_date 2016/11/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Abstract Global estimates of evapotranspiration remain a challenge. In this study, we show that the daily course of air temperature and specific humidity available at routine weather stations can be used to estimate evapotranspiration and the evaporative fraction, the ratio of latent heat flux to available energy at the surface. Indeed, the diurnal increase in air temperature reflects the magnitude of the sensible heat flux and the increase of specific humidity after sunrise reflects the amplitude of evapotranspiration. The method is physically constrained and based on the budget of heat and moisture in the boundary layer. Unlike land surface‐based estimates, the proposed boundary layer estimate does not rely on ad hoc surface resistance parameterizations (e.g., Penman‐Monteith). The proposed methodology can be applied to data collected at weather stations to estimate evapotranspiration and evaporative fraction under cloudy conditions and in the pre–remote sensing era.