CGRG Bibliography of Canadian Geomorphology
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Author : Eaton, B.; and Church, M.
Date : 2003.
Title : 1D numerical models of fluvial systems: some lessons and persistent mysteries.
Publication : Canadian Geophysical Union. Annual Meeting, May 10 -14, 2003. Banff Centre, Banff, Alberta.
Issue :
Page(s) :
Abstract
Computational power is fast becoming sufficient for the construction of 2D and 3D models describing fluvial systems. In light of this, we ask the question 'why bother with 1D models?' In short, 1D models are still the only possible way to investigate many field situations in which data are insufficient to set up 2D or 3D models, and for investigations over relatively long time periods and at relatively large scales. They are more parsimonious, and require construction of process-form relations at the scale of interest (a learning process, we claim) rather than brute force aggregation of process-form relations acting at smaller scales. They can be used to investigate long term evolutionary behaviour, in which there is no equilibrium state to which the model can be run. In this case, one must select criteria for determining when the state of interest is reached, and then to select additional criteria to test how well the model works. The capability of 1D models to elucidate the key factors controlling the coevolution of longitudinal profile and surface bed texture is demonstrated using examples from an aggrading alluvial fan. We also summarize a study that uses a 1D approach to model channel response to meander cutoffs and to predict further evolution. We conclude by discussing some of the persistent mysteries, including (1) derivation of adequate channel-scale characterizations of sediment transport, (2) determination of the geomorphic timescale in such models, and (3) incorporation of adjustments in the transverse components of the system.
Bibliography of Canadian Geomorphology