Advanced Ocean Modelling: Using Open-Source Software

82 3 Basics of Nonhydrostatic Modelling3.22.3 ResultsAs expected, the dense bottom layer gradually accelerates on the sloping bottom(Fig. 3.49). This creates a vertical shear flow. The shear flow becomes subject tothe Kelvin-Helmholtz instability process (see Sect. 3.10). Dynamical disturbancesappear after 70 min of simulation and create counter-clockwise rotating vortices. Atthis stage, the near-bottom flow has reached speeds of 80 cm/s.Fig. 3.49 Exercise 13: Density distributions (color shading and contours) at selected times of thesimulation. Red shading refers to the densest water