Estimation of turbulence parameters in a shallow sea using numerical simulation with sensitivity to vertical mixing parameterization

Abstract

Persian Gulf coastline and its depth are obtained based on ETOPO-2 data that has been interpolated and slightly smoothed onto a two-minute resolution. Cartesian coordinate system is used for horizontal and sigma coordinate with 10 layers is used for the vertical. From the turbulence schemes for the vertical diffusion available in the COHERENS, we tested four models to investigate the hydrodynamic characteristics of the Persian Gulf. These include two turbulence closure schemes: k-ε(one and half order), Mellor and Yamada (k-l, two and half order) and two algebraic schemes: Pacanowski and Philander (PP) formulation and flow-dependent parameterization. Noticeable difference between four schemes is found in the simulation of turbulent parameters. The turbulent closure schemes generally provide better results, but the algebraic schemes show turbulent parameters far from reality and they do not show substantial changes with time.