Critical dependence of morphodynamic models of fluvial and tidal systems on empirical downslope sediment transport

Baar, A. W.; Boechat Albernaz, M.; van Dijk, W. M.; Kleinhans, M. G.

Abstract

The morphological development of fluvial and tidal systems is forecast more and more frequently by models in scientific and engineering studies for decision making regarding climate change mitigation, flood control, navigation and engineering works. However, many existing morphodynamic models predict unrealistically high channel incision, which is often dampened by increased gravity-driven sediment transport on side-slopes by up to two orders of magnitude too high. Here we show that such arbitrary calibrations dramatically bias sediment dynamics, channel patterns, and rate of morphological change. For five different models bracketing a range of scales and environments, we found that it is impossible to calibrate a model on both sediment transport magnitude and morphology. Consequently, present calibration practice may cause an order magnitude error in either morphology or morphological change. We show how model design can be optimized for different applications. We discuss the major implications for model interpretation and a critical knowledge gap.

Citation

Baar, A. W., Boechat Albernaz, M., van Dijk, W. M., & Kleinhans, M. G. (2019). Critical dependence of morphodynamic models of fluvial and tidal systems on empirical downslope sediment transport. Nature communications, 10(1), Article 4903. https://doi.org/10.1038/s41467-019-12753-x

• Journal Article Type: Article
• Acceptance Date: Sep 26, 2019
• Online Publication Date: Oct 25, 2019
• Publication Date: 2019-12
• Deposit Date: Dec 6, 2019
• Publicly Available Date: Dec 6, 2019
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 1
• Article Number: 4903
• DOI: https://doi.org/10.1038/s41467-019-12753-x
• Keywords: Geomorphology; Hydrology; Sedimentology
• Public URL: https://hull-repository.worktribe.com/output/3001270
• Publisher URL: https://www.nature.com/articles/s41467-019-12753-x
• Additional Information: Received: 24 June 2019; Accepted: 26 September 2019; First Online: 25 October 2019; : The authors declare no competing interests.