Funding is provided to conduct a large coordinated experiment (HOME: Hawaiian Ocean Mixing Experiment) near the Hawaiian Ridge to determine whether sites with rough topography are responsible for the mixing of the global ocean. The goals are to identify the major energy pathways for ocean mixing and achieve an approximate energy budget for the region. The Near-field experiment of the HOME project focuses on the investigation of the dynamical processes in the immediate vicinity of the Hawaiian Ridge, and especially the response to barotropic tidal forcing including generation of low- and high-mode internal waves, propagation and turbulent dissipation and mixing. This sub-project will focus on (i) defining the vertical structure of the individual tidal constituents at several distances from the source and determine the portion that is phase-locked with the barotropic tide; (ii) measuring the tidal contribution to shear, strain, Richardson number, and other mixing indicators such as Thorpe scale; (iii) determining the contribution of other energy sources for mixing, such as mesoscale currents and high-frequency internal waves; (iv) describing the modification of the background internal wave spectrum as the Hawaiian Ridge is approached; and (v) studying the relationship between observations of shear, strain, Thorpe scale, etc., and the direct observations of turbulent mixing obtained by other Nearfield investigators. Three moorings will be deployed starting at the top of the Ridge in the Kauai Channel and extending to the south: a short mooring at the top of the Ridge, a mid-depth mooring deployed at about 1500m, and a deep mooring at 4000m. The three moorings will be deployed in August, 2002, just before the intensive profiling of the Nearfield experiment begins, and will be recovered three months later. The instrumentation will include: Doppler current profilers, temperature recorders, and temperature-conductivity recorders.
