Research Of M₂ Internal Tide Energy Flux In Hawaii Ocean Based On HAMSOM Model Simulation

Internal tide is a common motion in the ocean, which has the same frequency as the induced tide. Internal tide is arising due to the interaction of barotropic tide and topography. The generation of internal tide is an important source for barotropic tides and also the mechanic energy source for ocean mixing. This article base on the M2 internal tide produced around the rough Hawaii ridge. As the Hawaiian Ridge is the site of the most intense surface tide loss per unit area in the global deep ocean (Egbert and Ray 2001; Simmons et al.2004), it is a suitable place for internal tide simulation, so in this article author chooses the Hawaiian ocean as the simulation area.In this article based on the analyzing of the theories and methods on internal tide, author uses a three dimensional Ocean model, which developed by Hamburg university of Germany called HAMSOM (Hamburg Shelf Ocean Model) , to simulate the internal tide induced by M2 tide under the condition of rough topography. Before this simulation, author proved the validation of the model. Firstly added eight mainly tidal components and some outside forces such sea surface winds into the model to simulate velocity and elevation field for one month. Then did harmonic analysis to get M2 tide amplitude and phase which match the tidal characteristic well in Hawaiian area. Moreover, compares the elevation of model results with six and long term tide-gauge station in the range of Hawaii area. Secondly, as proved the validation of the model, author uses a singe frequency tide component M2 tide as the only force of the model to do the simulation in the rough topography area of Hawaiian ocean. The M2 internal tide can be found by the analysis of the variation of isopycnal and velocity perturbation. And then analysis the internal tide vertical structure, horizontal velocity, displacement of isopycnal and internal tide energy flux in this M2 baroclinic tide induced model. From the results author found the periodic variation caused by internal tide. Meanwhile calculates the M2 internal tide energy flux using the velocity and density data from the model, the magnitude of energy flux in the model domain varies from 100W/m to 10kW/m. Further more extract M2 internal tide signal from the altimeter data, and also calculated the internal energy flux which has the magnitude of 100W/m to 1kW/m. There is some disagreement in results of these two method, so author gives out some possible explanation might cause the problem.Because of the importance of the research on internal tide, it is useful to do research on the M2 internal tide. And it is a fist time on the simulation of internal tide by HAMSOM, so it makes sense not only for the development and application of this model, and also for the research of internal tide.