Evolution and distribution of TKE production and dissipation within stratified flow over topography.

Analysis is presented of detailed observations of turbulence in stratified flow over topography. Key results are: 1) Directly measured dissipative energy losses due to skin friction and an internal hydraulic transition are relatively small, each accounting for approximately 10% of the mean flow energy loss, and 2) Production and dissipation of turbulent kinetic energy in flow over the topographic feature are in approximate balance throughout the transition from sub-to super-critical mean flow. The study is two-dimensional and a closed energy budget through direct measurement remains elusive; it is concluded that horizontal aspects of barotropic form drag such as eddy-shedding are responsible for as much as 30 - 40% of the mean flow energy loss.