Benchmarking flexible meshes and regular grids for large-scale fluvial inundation modelling

摘要: Abstract Damage resulting from flood events is increasing world-wide, requiring the implementation of mitigation and adaption measures. To facilitate their implementation, it essential to correctly model hazard at large scale, yet fine spatial resolution. reduce computational load models, flexible meshes are an efficient means compared uniform regular grids. Yet, thus far they have been applied only for bespoke small-scale studies a high level priori grid preparation. better understand possible advantages as well shortcomings application large-scale riverine inundation simulations, three different were derived Height Above Nearest Drainage (HAND) data with grids under identical spatially explicit hydrologic forcing by using GLOFRIM, framework integrated hydrologic-hydrodynamic modelling. By output global PCR-GLOBWB was passed hydrodynamic Delft3D Flexible Mesh. Results show that applying can be beneficial depending on envisaged purpose. For discharge similar accuracy obtained between grids, former generally having shorter run times. extent however, coarser gridding in upstream areas results poorer performance if assessed contingency maps. Moreover, while ratio minimum maximum resolution has limited impact water estimates may stronger influenced larger cells. . As this study presents small set realizations, additional research needs unravel how methods used choices discretizations influence performance. Generally, particularly discretization process involves more options, bringing responsibilities user. Once decision made purpose, valuable addition modelling approaches where short times essential, facilitating ensemble or operational forecasting.