MEPS 158:275-281 (1997)  -  doi:10.3354/meps158275

Using random walk models to simulate the vertical distribution of particles in a turbulent water column

André W. Visser*

Danish Institute for Fisheries Research, Department of Marine and Coastal Ecology, Kavalergården 6, DK-2920 Charlottenlund, Denmark

Random walk simulation has the potential to be an extremely powerful tool in the investigation of turbulence in environmental processes. However, care must be taken in applying such simulations to the motion of particles in turbulent marine systems where turbulent diffusivity is commonly spatially non-uniform. The problems associated with this non-uniformity are far from negligible and have been recognised for quite some time. However, incorrect implementations continue to appear in the literature. In this note computer simulations are presented to illustrate how and why these implementations are incorrect, and a simple technique that can properly simulate turbulent diffusion in the marine environment is discussed.

Random walk · Turbulence · Diffusivity · Numerical simulation

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