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LERAT ET AL.: VALUE OF UPSTREAM FLOW MEASUREMENTS X - 17humid catchments, with mean precipitation and PE on TOTAL of 970 mm and 660 mm,290respectively.5. ResultsIn this section, we analyze the results of the three models applied to the 192 nestedcatchments at the daily time-step.Table 3 presents the statistics of the classical Nash-Sutcliffe efficiency (CEff) for the Table 3three models in calibration and validation modes on UP and TOTAL stations. Statistics295are calculated over the 384 subperiods (two subperiods for each of the 192 catchmenttel-00392240, version 1 - 5 Jun 2009300305310pairs).The results for all models on this table indicate that the calibration can be consideredas robust with a limited decrease in performance between the calibration and validationmodes.All models provide satisfactory results in calibration and validation mode on the downstreampoint TOTAL with a 25% quantile of CEff greater than 0.8. Figure 4 locates Figure 4catchments with lower performance: around the Parisian basin where groundwater contributionis poorly handled by the rainfall-runoff model (CEff criteria below 0.7 in validationmode). A similar level of performance is obtained on small catchments in the upper Loirebasin and around the Mediterranean coast, where faster catchment response times aredifficult to model at the daily time-step.Model performance is lower at the upstream point UP for both the benchmark andthe UP-Sim model (performance of the UP-Meas is not evaluated on this point becausemeasured upstream flow constitutes one of the inputs of this model). The UP-Sim modelpresents a much better performance than the benchmark on this point, which is not sur-D R A F T July 24, 2008, 3:43pm D R A F T