| Sumario: | In view of the water scarcity that affects the province of Mendoza, Argentina, information
on reference crop evapotranspiration (ET0) is crucial for irrigation scheduling.
Data that are not generally available is required for the determination of ET0, with the
Penman-Monteith FAO56 equation (PM). The Hargreaves equation (HG), which only
requires air temperature data, represents an alternative to calculate ET0, after its local
or regional calibration with PM. In this paper, the Hargreaves equation was calibrated
locally by means of annual (Ca) and monthly (Cm,j) adjustment coefficients for the
northern oasis of Mendoza. Also, a regionalisation of the Ca was performed considering
environmental variables. The local adjustment with both coefficients made it possible to
correct the positive bias that indicated an overestimation of HG with respect to PM in 12
meteorological stations. The mean value of the root mean square error decreased from
0.80 mm day-1 to 0.57 mm day-1 with the Ca adjustment coefficient, and to 0.55 mm day-1
with the Cm,j adjustment coefficient, while the absolute error decreased from 0.63 to 0.42
and 0.39, respectively. Wind speed was the variable that best explained the regional
variability of the Ca (R2 = 0.64).
|
|---|
Biblioteca Digital de Vanguardia