Abstract. This study documents the development of a semi-distributed hydrological
model aimed at reflecting the dominant controls on observed streamflow
spatial variability. The process is presented through the case study of the
Thur catchment (Switzerland, 1702 km2), an alpine and pre-alpine
catchment where streamflow (measured at 10 subcatchments) has different
spatial characteristics in terms of amounts, seasonal patterns, and dominance of baseflow. In order to appraise the dominant controls on
streamflow spatial variability and build a model that reflects them, we
follow a two-stage approach. In a first stage, we identify the main
climatic or landscape properties that control the spatial variability of
streamflow signatures. This stage is based on correlation analysis,
complemented by expert judgement to identify the most plausible cause–effect
relationships. In a second stage, the results of the previous analysis are
used to develop a set of model experiments aimed at determining an
appropriate model representation of the Thur catchment. These experiments
confirm that only a hydrological model that accounts for the heterogeneity
of precipitation, snow-related processes, and landscape features such as
geology produces hydrographs that have signatures similar to the observed
ones. This model provides consistent results in space–time validation,
which is promising for predictions in ungauged basins. The presented
methodology for model building can be transferred to other case studies,
since the data used in this work (meteorological variables, streamflow,
morphology, and geology maps) are available in numerous regions around the
globe.
Applying Deterministic Distributed Hydrological Model for Stream Flow Data Reproduction. A Case Study of Cu De Catchment, Vietnam
