Hydrological modelling of a medium-size mountainous catchment from incomplete meteorological data

Abstract

The US National Weather Service River Forecast System (NWSRFS)-snow accumulation and ablation model, as well as the soil moisture accounting model are developed and tested for purposes of conceptually modelling a medium-size mountainous catchment, i.e. the Mesochora catchment in Central Greece, by using incomplete precipitation and temperature daily records. A combinatorial technique of the Thiessen method and station availability condition, including elevation correction, is adopted for areal and elevation integration of snowmelt model input data. For such an input modelling, the snowmelt model has been proved capable of predicting the initiation of snow accumulation in the fall and the gradual melting of the snowpack in the late winter and spring, while the rainfall-runoff model, which accepts as input the snowmelt model output ‘rain plus melt’, has also proved capable of accurately reproducing both the magnitude and timing of the annual and monthly runoff. On a daily basis, the runoff model reproduces satisfactorily the historic data, while some discrepancies arise owing to antecedent dry conditions and extreme rainfalls.