Lana Erofeeva
College of Oceanic & Atmospheric Sciences, Oregon State University, Corvallis, OR.

Laurie Padman
Earth & Space Research, Seattle, Washington.

Gary Egbert
College of Oceanic & Atmospheric Sciences, Oregon State University, Corvallis, OR.


We describe the application of a generalized inverse approach for assimilation of vessel-mounted acoustic Doppler current profiler (VM-ADCP) data into numerical inverse solutions for the barotropic tides. The derived estimates of tidal currents can be used to detide the VM-ADCP data and expose underlying mean circulation. We consider the example of data assimilation for prediction of tidal currents in the Ross Sea.

We obtain a prior solution by solving the non-linear shallow water equations by time stepping using a linear bottom friction parameterization and elevation open boundary conditions obtained from a Circum Antarctic tide model. The prior solution provides reasonably good fit to most available moored current meter data. The various data combinations were used for assimilation into, and validation of, inverse solutions. Fitting either the current mooring or the ADCP data leads to only small changes in the prior solution currents except over the shelf break where energetic diurnal topographic vorticity waves are present. We also show that the dynamics embedded in the representer functions provides reasonable tidal corrections even with no prior information about forcing at open boundaries.