6533b7d0fe1ef96bd125b638

RESEARCH PRODUCT

Estimation of Evapotranspiration by Hargreaves Formula and Remotely Sensed Data in Semi-arid Mediterranean Areas

C. Di StefanoVito Ferro

subject

HydrologyCrop coefficientPixelComputer Science::Computer Vision and Pattern RecognitionEvapotranspirationEnergy balanceEnvironmental scienceAquatic ScienceStructural basinAlbedoAridMultispectral pattern recognitionRemote sensing

description

Abstract A methodology is proposed for estimating evapotranspiration by Hargreaves formula and image analysis of remotely sensed data. At first, for a large sicilian basin (Belice basin), theactualevapotranspiration values are estimated by the energy balance equation, spectral data of two Landsat TM images and ground agrometereological measurements. Then theseactualevapotranspiration estimates and thereferenceevapotranspiration values obtained by a slightly modified Hargreaves formula, which incorporates the outgoing short-wave radiation and an albedo coefficient equal to 0·23, are used for calculating suitable crop coefficients. Finally, the minimum area of each land-use map unit, obtained by aggregating an increasing number of image pixels, is determined that is useful to enable a stable estimate of crop coefficient (kc).

yearjournalcountryeditionlanguage
1997-11-01Journal of Agricultural Engineering Research
https://doi.org/10.1006/jaer.1997.0166