Two major challenges facing the Hawaii Ocean-Mixing Experiment (HOME) are to isolate baroclinic variability associated with the tides from a background of energetic processes, and to extrapolate the results obtained from HOME to other regions of the ocean where the tides are an important energy source for pelagic mixing. In both regards, numerical models play an essential role, providing the means for interpretation of a comprehensive but undersampled set of observations. Given the complexity of the flow field in the vicinity of the Hawaiian Ridge, a combination of observations and models will be needed to quantitatively map tidal fields in this area. In particular, model based data assimilation provides an optimal way to combine all available data (historical data, satellite altimetry data, plus data collected during HOME) into dynamically consistent estimates of barotropic and baroclinic energy fluxes, and hence to constrain the amount of tidal energy available for localized mixing. Models can also be used to determine the topographic and oceanic conditions favorable for energetic tide-induced mixing. Finally, models provide a dynamical context in which to synthesize and generalize the results obtained from the various HOME programs. In particular, HOME will provide the opportunity to evaluate various turbulent closure schemes against direct and integrated measures of dissipation and diapycnal mixing.
To achieve these goals, the HOME modeling program will consist of two focus areas: data assimilation studies of both the barotropic and baroclinic tides conducted by Gary Egbert (OSU) and Richard Ray (NASA), and investigations into the generation of the baroclinic tide at the Hawaiian Ridge by Mark Merrifield (UH) and Peter Holloway (ADFA/UNSW).