The effect of including a (non-)linear Muskingum-Cunge river routing approach in VIC was carried out and tested. The implementation appeared to be non-trivial.
Implementing a (non-)linear Muskingum-Cunge river routing approach in VIC - Case study on the flooding event in the Thur Catchment in May/June 2013
The VIC (Variable Infiltration Capacity) model is a three soil layer macroscale hydrological model. VIC has been widely used in studies on climatology topics, land-atmosphere interactions and water resource management subjects. Water transport in the VIC model only happens in the vertical direction based on hydrological principles (runoff and baseflow [mm/day]). In order to simulate river flow (=horizontal water transport) and compare the model output with observations [m3/s], a hydraulic part needs to be included (=routing structure).
The simulation of river flow contains many complex processes, like floodplain inundation during high discharges and water that crosses weirs and other structures during low discharges. Currently, many different river flow models are in use. Each of these schemes emphasize on different parts of river routing and neglect others. Due to these simplifications improvement is still needed. This research included a model development study and a case study on the flooding event in Central Europe (May-June 2013). The analysis of the simulation results was accomplished for outflow discharge and the behavior of a flood wave.
The results were analyzed based on the discharge at the outlet and the behavior of a flood wave. Two cases were studied: the effects of including a
- linear Muskingum-Cunge approach
- non-linear Muskingum-Cunge approach
in the model on flood wave propagation. The routing was tested on a simple 100-cells linear catchment with uniform hydrological inflow data. The behavior of the flood wave simulated with the (non-)linear Muskingum-Cunge model partly proved that it is possible to include a different routing method without losing significant accuracy. The implementation appeared to be non-trivial.