A Theoretical, Empirical and Experimental Investigation of the Spatial Scaling and Dynamics of Braided Rivers

9628393 Efi Foufoula Understanding the space-time variability of the morphology of braided rivers is a challenging and difficult scientific problem. Lack of data and process complexity have prohibited quantitative studies and hindered this area of research. Improved satellite technology for remote sensing monitoring and experimental (laboratory) production of braided rivers offer essential information. The proposed theoretical, empirical and experimental investigations, focused on understanding scale invariances and scale dependencies (collectively called scale relationships) in the geometry of braided rivers and provide physical interpretations of these relationships. In particular, the goal is to quantitatively study and characterize the spatial and temporal structure of braided rivers and ultimately provide a generalized conceptual framework under which such systems can be studied for both physical understanding and prediction. The specific objectives of the proposed research are: Study scale relations in the morphology (planforms) of braided rivers. Study and statistically characterize the evolution of planforms and spatial patterns of braided rivers. Study the connection of the spatial and temporal structure of braided river morphology to underlying physical mechanism via experimental work and computer simulation. The experimental facility for the laboratory production and monitoring of braided rivers will be used by and interdisciplinary research team consisting of a geologist, a hydrologist and an experimental/theoretical physicist. The main theoretical innovations will be (1) development of a mathematically rigorous frame-work to address questions of scale-invariances and scale-dependencies of complex systems, (2)integration of spatial and temporal scaling ideas under a single framework, and (3) use of a simple braided river model to investigate physical mechanisms responsible for observed spatial and temporal structures in the morphology of braided rivers. The fr amework for analysis and interpretation of these complex dynamical systems will incorporate notions of multiscaling, self-organized criticality and deterministic systems with complex behavior. Finding can be applied in (1) prediction of the evolution of braided rivers for hydraulic engineering and environmental studies and (2) scale relationships in geometric characteristics of braided rivers of different size for transferability studies.