The inertial chimney: The near‐inertial energy drainage from the ocean surface to the deep layer

A three‐dimensional primitive equation numerical model is used to study the behavior of near‐inertial waves generated by surface wind stress on an ƒ plane. The model is fixed depth with a rigid lid on the surface and is horizontally periodic. This study shows the behaviors of the wind‐generated near‐inertial waves for four different eddies: (1) a subtropical cold‐core eddy, (2) a subtropical warm‐core eddy, (3) a California subsurface warm‐core eddy, and (4) the Gulf Stream warm‐core ring. The mean secondary circulation generated by the wind‐eddy interaction has magnitude to comparable to that of the Ekman current, and its characteristics are determined by the relative angle between wind and current. The propagation characteristics of near‐inertial waves are quite different depending upon the sign of the relative vorticity. In a cyclonic eddy, near‐inertial wave propagation is outward from the core of the eddy. The propagation direction in an anticyclonic eddy is downward and toward the core. Vertically propagating waves inside the eddy are trapped above a critical layer and slowly dissipated by parameterized viscous effects. The model shows that anticyclones efficiently drain near‐inertial energy from the surface to the deep layer below the thermocline.