ABSTRACT
A NEW FORMULA TO DETERMINE EVAPOTRANSPIRATION IN CHILE

Juan Tosso T.1
 

A study was conducted in order to analize the chilean climatic and class A pan evaporation data. From this analysis a mathematical formula was obtained through wich it is possible to estimate the class A pan evaporation. The formula is represented by the following general equation:

ETb = Kb X R X CTM X CHR X CV X CTD X CEL X CP

With the information of pan evaporation, which is considered as an index of potential evapotranspiration and knowing the K coefficients, it is possible to estimate the actual evapotranspiration for a specific crop according to the following equation:

ET = K X EB

In the present study, the K coeefficients for different crops are given in a table. Part of them are the results of research conducted by the author at Platina Experimental Station, Santiago.

Keywords:
1Ing. Agr., M.S., Programa de Riego, Estación Experimental La Platina, Instituto de Investigaciones Agropecuarias (INIA), Casilla 5427, Santiago, Chile.