On width function-based unit hydrographs deduced from separately random self-similar river networks and rainfall variability: Discussion of “Coding random self-similar river networks and calculating geometric distances: 1. General methodology” and “2. Application to runoff simulations”

Transferring measured discharge time series: Large‐scale comparison of Top‐kriging to geomorphology‐based inverse modeling

“…[] and similar to Top‐kriging, this approach distinguishes runoff generation over hillslopes (production function) from flow routing in the stream network (transfer function). The approach focuses only on the transfer function, which is built from a morphometric description of the flow path within the river network [ Cudennec et al ., ; Cudennec and Fouad , ; Cudennec , ; Aouissi et al ., ]. The hydraulic length x c , defined as the distances to the outlet from any point within the river network, is estimated from a digital elevation model (DEM) of the catchment and is described as a probability density function ( pdf ( x c )) of distances.…”

Geomorphometry-based modelling of discharge series in ungauged basins – Robustness regarding DEM sources

“…Considering a water drop falling inside a basin and moving towards the outlet, the hydraulic length L corresponds to the travelling distance within the river network. Following the assumption of a linear transfer function (Blöschl and Sivapalan, 1995;Robinson et al, 1995;Cudennec, 2007), pdf(t) = TF is then deduced from pdf(L) thanks to the estimation of the average river flow velocity v. This characteristic velocity has been regionalized for the whole Brittany by de Lavenne (2014) as in Eq. 2, where L is the mean hydraulic length of the considered basin.…”

“…hydrographs, and derived statistics of regimes (Blöschl et al, 2013;Hrachowitz et al, 2013). Since the beginning of DEM availability, geomorphology-based (or geomorphometry-based) approaches have proposed parsimonious, robust and flexible models with few calibration needs (Cudennec, 2007;Rigon et al, 2015). The new availability of quasi-worldwide DEMs open new avenues for applications to simulate hydrographs with short time steps at ungauged sites, which can then be used to explore regime statistics.…”

Assessment of freshwater discharge into a coastal bay through multi-basin ensemble hydrological modelling

“…Following pioneer intuitions (Surkan, 1969), the geomorphology-based unit hydrograph framework has been developed through two major approaches (Cudennec, 2007;Rigon et al, 2016): the one based on the hierarchical topology of the branched out river network (e.g. Rodríguez-Iturbe and Valdés, 1979;Cudennec et al, 2004) and the other one based on easily observable geomorphometric width and area functions (Kirkby, 1976;Snell and Sivapalan, 1994;Robinson et al, 1995).…”

“…This study focused only on the T F through the river network. It was constructed from a geomorphometric description of the flow paths (Cudennec et al, 2004;Cudennec, 2007) which values the strong hydrogeomorphological structure-function relationship (Cudennec and de Lavenne, 2015;Rigon et al, 2016). For each pixel of the digital elevation model (DEM), the flow path to the outlet is performed and the hydraulic length L corresponds to the length of the channelized part of the path within the river network only.…”