Assessment of the METRIC model in the estimation of instantaneous values of sensible and latent heat fluxes over a drip-irrigated Merlot vineyard using Landsat images

Marcos Carrasco-Benavides; Samuel Ortega-Farías; Octavio Lagos; Jan Kleissl; José Carlos Neves Epiphanio; Lênio Soares Galvão


The performance of the METRIC (Mapping EvapoTranspiration at high Resolution with Internalized Calibration) model was evaluated to estimate instantaneous sensible (H i) and latent heat fluxes (LE i) over an experimental plot of a drip-irrigated Merlot vineyard (Vitis vinifera L.) of 4.25 ha (35°25' LS; 71°32' LW; 125 m.a.s.l). This study was carried out using data obtained between the years 2006 and 2009. Ground data of sensible and latent heat fluxes were measured by an Eddy Covariance (EC) system. METRIC estimations of H i and LE i considered fifteen days where Landsat scenes were available. The pixel by pixel METRIC estimations were averaged using the pixels inside the experimental plot. Measured and estimated instantaneous values of H i and LE i were analyzed using the coefficient of determination (R 2) and the mean absolute error (MAE). Results indicate that METRIC overestimated H i by 10% (MAE = 39 W m -2) while LE i was overestimated by 14% (MAE = 33 W m -2). Results of this study indicated that the self-calibration of METRIC in H i allowed obtain acceptable values of LE i .

Más información

Editorial: Instituto Nacional de Pesquisas Espaciais (INPË)
Fecha de publicación: 2013
Año de Inicio/Término: 13-18 abril 2013
Página de inicio: 490
Página final: 497
Idioma: english