On Deep-Water Renewals in Indian Arm, British Columbia: Sensitivity to the Production of Turbulent Kinetic Energy Caused by Horizontal Variations in the Flow Field

Abstract

A two-dimensional (i.e., laterally averaged) numerical model of the circulation in Burrard Inlet and Indian Arm near British Columbia, Canada, is used to examine the sensitivity of deep-water renewal events in Indian Arm to the turbulent mixing in the lee of the narrow sills in Burrard Inlet. Horizontal variations in the flow field can have an important influence on the production of turbulent kinetic energy near the sills and therefore also on the renewal events in Indian Arm. An ad hoc modification to the expression for the production of turbulent kinetic energy, required to obtain an acceptable simulation downstream of Second Narrows in Burrard Inlet, also results in a reasonable simulation of the observed circulation in Indian Arm. The modified laterally averaged model can reproduce the main features of the circulation away from the narrow sills. However, it seems that a three-dimensional model will be required if the circulation is to be simulated with greater accuracy and without the ad hoc modification, which has a free parameter.