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Giles Wiggs Sheffield Centre for International Drylands Research Aeolian dune processes and dynamics 2004 Joint Assembly Montreal, Canada. Dunes in equilibrium…. Best 1993. Measurements of mean windspeed and sediment transport. windspeed. sand flux.
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Giles Wiggs Sheffield Centre for International Drylands Research Aeolian dune processes and dynamics 2004 Joint Assembly Montreal, Canada
Dunes in equilibrium…. Best 1993
Measurements of mean windspeed and sediment transport windspeed sand flux McKenna-Neumann et al 1997 Wiggs 2001
U* Measurements of shear velocity shear stress mean shear velocity Wiggs 2001 Lancaster et al 1996 turbulence
Measurements of Reynolds turbulent stress Reynolds stress Streamline angle
Calibration of numerical models Parsons et al 2004
Werner 1995 Other modelling approaches - complex systems Baas 2002 Momiji et al 2000
Other modelling approaches - analytical solutions (Hersen, Sauermann, Herrmann, Andreotti) Schwammle & Herrmann 2003 Hersen 2004
Hersen et al 2004 Output sand flux Dune width
Dunes in dis-equilibrium….? Hersen 2004 Parker Gay Jr 1999
Conclusions • dune research is in a healthy state! • measurements of airflow structure improving BUT requires improved understanding of turbulence / sediment transport relationships • calibration of computational models allowing greater understanding of form/flow interactions • results of analytical models suggest a requirement for more fieldwork focusing on: • dynamics of sediment transfers at the dune and inter-dune scale • longer time-series measurements of dune evolution