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

Random walk simulation has the potential to be an extremely powerful tool in the ~nvestigation of turbulence in environmental processes. However, care must be taken in applylng such simulat~ons to the mohon of particles in turbulent marine systems where turbulent diffusivity IS conlmonly spatially non-uniform. The problems associated with this nonuniformity are far from negligible and have been recognised for quite some time. However, incorrect implementat~ons continue to appear in the Literature. In this note computer simulations are presented to illustrate how and why these implementations are incorrect, and a slmple technique that can properly slmulate turbulent diffusion in the marine environment is discussed.