An evaluation of thornthwaite's water balance technique in predicting stream runoff in costa rica

Abstract

The Thornthwaite water balance technique is used to predict monthly stream runoff from Rio Macho basin in Costa Rica. The method was tested by comparing observed and predicted runoff over a 15 water-year period. The study shows that this method provides mean annual and monthly estimates in close agreement with measured values. Generally these mean estimated values fall between the 90% confidence intervals for the measured runoff. These results indicate that the Thornthwaite method can be satisfactorily applied to estimate mean monthly streamflow in the uplands of Costa Rica. © 1986 Taylor & Francis Group, LLC.