Print Email Facebook Twitter Scale effect challenges in urban hydrology highlighted with a distributed hydrological model Title Scale effect challenges in urban hydrology highlighted with a distributed hydrological model Author Ichiba, Abdellah (Institut Pierre Simon Laplace; Conseil Départemental du Val-de-Marne) Gires, Auguste (Institut Pierre Simon Laplace) Tchiguirinskaia, Ioulia (Institut Pierre Simon Laplace) Schertzer, Daniel (Institut Pierre Simon Laplace) Bompard, Philippe (Conseil Départemental du Val-de-Marne) ten Veldhuis, Marie-claire (TU Delft Water Resources) Date 2018-01-15 Abstract Hydrological models are extensively used in urban water management, development and evaluation of future scenarios and research activities. There is a growing interest in the development of fully distributed and grid-based models. However, some complex questions related to scale effects are not yet fully understood and still remain open issues in urban hydrology. In this paper we propose a two-step investigation framework to illustrate the extent of scale effects in urban hydrology. First, fractal tools are used to highlight the scale dependence observed within distributed data input into urban hydrological models. Then an intensive multi-scale modelling work is carried out to understand scale effects on hydrological model performance. Investigations are conducted using a fully distributed and physically based model, Multi-Hydro, developed at Ecole des Ponts ParisTech. The model is implemented at 17 spatial resolutions ranging from 100 to 5m. Results clearly exhibit scale effect challenges in urban hydrology modelling. The applicability of fractal concepts highlights the scale dependence observed within distributed data. Patterns of geophysical data change when the size of the observation pixel changes. The multi-scale modelling investigation confirms scale effects on hydrological model performance. Results are analysed over three ranges of scales identified in the fractal analysis and confirmed through modelling. This work also discusses some remaining issues in urban hydrology modelling related to the availability of high-quality data at high resolutions, and model numerical instabilities as well as the computation time requirements. The main findings of this paper enable a replacement of traditional methods of model calibration by innovative methods of model resolution alteration based on the spatial data variability and scaling of flows in urban hydrology. To reference this document use: http://resolver.tudelft.nl/uuid:fb35bf45-43c5-45cf-9a8d-4b7450be19d5 DOI https://doi.org/10.5194/hess-22-331-2018 ISSN 1027-5606 Source Hydrology and Earth System Sciences, 22 (1), 331-350 Part of collection Institutional Repository Document type journal article Rights © 2018 Abdellah Ichiba, Auguste Gires, Ioulia Tchiguirinskaia, Daniel Schertzer, Philippe Bompard, Marie-claire ten Veldhuis Files PDF hess_22_331_2018.pdf 11.45 MB Close viewer /islandora/object/uuid:fb35bf45-43c5-45cf-9a8d-4b7450be19d5/datastream/OBJ/view