*4.1. Long-term ET*

Long-term ET observations were substantially greater than the MODIS model predictions and greater but more similar to the SWAT model predictions. Observed ET averaged across all months and flux towers was 54.6 mm/mo (Figure 3). This value was 13% greater than SWAT's prediction (48.5 mm/mo), 83% greater than MODIS's prediction (29.8 mm/mo) (Figure 3). In addition, observed long-term ET in the upper Kings River decreased with elevation at a markedly steeper rate than the MODIS model predicted. Based on the flux tower network, ET decreased with elevation at a rate of −0.013 mm mo<sup>−</sup><sup>1</sup> m<sup>−</sup><sup>1</sup> (Figure 3). This rate was fairly close (7.7%) to the SWAT model prediction of −0.012 mm mo<sup>−</sup><sup>1</sup> m<sup>−</sup><sup>1</sup> (Figure 3). In contrast, the MODIS model predicted an elevational trend of only −0.0025 mm mo<sup>−</sup><sup>1</sup> m<sup>−</sup>1, one-fifth the observed value. These results showed that both magnitude and elevational trend in long-term ET were predicted much more accurately by SWAT than MODIS.
