The effect of climate change on stage-discharge bondary conditions in interconnected river delta (sub) models

Climate change impacts river deltas world-wide, now and in the future. To study impacts and mitigate effects, hydrodynamic models are often used. Developing these models poses challenges to its developers: the boundaries of these models should be chosen such that the model generates accurate predictions within the domain of interest. This is a fundamental, but difficult choice (Jakeman et al., 2006). As deltas<br/>are often interconnected networks of rivers and canals both bifurcating and confluencing, creating backwater curves, system dynamics quickly become complex. Choosing suitable boundaries is therefore not straightforward: modelling only part of a delta (i.e. using a submodel) might not capture important feedback mechanisms, increasing uncertainty due to boundary conditions (Berends et al., 2018), which can travel far into the model (Domeneghetti et al., 2013). Contrary:<br/>increasing the domain increases computational expenses. Finding a balance is up to the developer. This research investigates to what extent hydrodynamics in such complex networks can be modelled in parts by addressing the accuracy of boundary conditions of such submodels.