Linking space–time scale in hydrological modelling with respect to global climate change: Part 1. Models, model properties, and experimental design

Abstract

The link between space and time scales in hydrological modelling, in most cases, is related to both the model structure and the implementation procedure, and this makes the hydrological predictions differ from one model to another. A monthly water balance (MWB) model and the snow accumulation–ablation (SAA) and soil moisture accounting (SMA) models of the US National Weather Service (US NWS) were examined and compared on a medium-sized mountainous catchment (the Mesochora catchment in Central Greece) under historical climate conditions. The analysis focused on the model time resolution, structure, input data, and calibration process. The best results were obtained from the US NWS models, which ran on smaller time increments (6 h step for the SAA model and daily step for the SMA model), were explicitly parameterized, and for which the input data and parameter estimate procedures were more accurate. The main model evaluation criteria were the NTD efficiency measure for the 15 year study period and the comparison of the measured and predicted streamflow by the average month. The hydrological results for both models (SAA–SMA and MWB) showed small differences in the monthly runoff values and a greater interannual variability for the SAA–SMA models. The monthly soil moisture predictions by the models were different. The hydrological simulation under global climate change conditions is presented in the companion paper.