Ground heat flux estimated from surface soil temperature

This paper presents a novel method that allows the diurnal variation of ground heat flux to be computed from the corresponding time series measurement of surface soil temperature. Soil temperature and soil heat flux over time at one location are uniquely related through a half-order derivative/integral operator when heat transfer in a soil matrix is described by a one-dimensional diffusion equation with a constant diffusivity parameter. Both simulated and observed data have been used to test the method. The case study suggests that the derived relationships between soil heat flux and soil temperature under idealized conditions provide satisfactory approximations for practical purposes. Close agreement of the estimated variables with observations indicates chat this proposed method is promising. Its potential applications include the estimation of the regional energy balance at the land surface using remote sensing observations. (C) 1999 Elsevier Science B.V. All rights reserved.