Table 5.1. Calibration and validation statistics for the Santa River
Sub-watershed
n 120 120 120 120 120 120 120 120 * 120 120 120 120 120 120 120 120
Calibration RMSE BIAS 0.43 39% 0.51 9% 1.37 1% 0.54 7% 0.43 9% 0.26 20% 0.73 35% 1.70 6% * * 0.34 24% 0.98 3% 0.29 -7% 0.03 3% 0.19 -12% 0.01 4% 0.05 17% 0.01 290%
Ef 0.63 0.64 0.72 0.73 0.65 0.30 -0.60 0.25 * 0.34 0.34 0.64 0.70 0.54 0.69 0.67 -165.00
Period 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 * 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989 1979-1989
n 120 120 120 120 120 120 120 120 * 120 120 120 120 120 120 120 120
Validation RMSE 0.43 0.53 1.50 0.55 0.45 0.36 0.92 0.74 * 0.38 0.79 0.23 0.03 0.20 0.02 0.05 0.01
BIAS 44% 13% 20% -4% -2% -4% -15% -44% * 4% -17% -23% 1% -9% 1% 16% 360%
Ef 0.50 0.55 0.73 0.63 0.63 0.63 0.13 -1.60 * 0.24 0.20 0.20 0.72 0.40 0.77 0.61 -190.00
Source: Figure generated for the report by SEI, 2009. Note: Root Mean Square Error (RMSE) is a good measure of precision or repeatability, which is the degree to which repeated measurements under unchanged conditions show the same results. Bias: perceptual bias; and Ef: Nash-Sutcliffe efficiency coefficient is used to assess the predictive power of hydrological models. It is a criterion that measures the fraction of the variance of observed values explained by the model. It ranges from minus infinity to 1.0. An efficiency of 1 corresponds to a perfect match of modeled discharge to the observed data. Therefore, large positive values close to 1.0 are sought.
Assessment of the Impacts of Climate Change on Mountain Hydrology
1 - La Recreta 2 - Pachacoto 3 - Querococha 4 - Olleros 5 - Quillcay 6 - Chancos 7 - Llanganuco 8 - Paron 9 - Artesoncocha 10 - Colcas 11 - Los Cedros 12 - Quitaracsa 13 - La Balsa 14 - Corongo (Manta) 15 Chuquicara 16 - Tablachaca (Condorcerro) 17 - Puente Carretera
Period 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 * 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979 1969-1979
49