Assimilating DART Data into an Upgrade of VDatum for the US West Coast

The U.S. national VDatum program has an ongoing project to upgrade VDatum for the entire U.S. West Coast. In this study, we have tested a conceptually simple tides assimilation scheme based on linearized shallow water equations that will be used by the upgrade. It assimilates the data recorded by deep ocean bottom pressure recorders to optimize/improve the offshore boundary conditions for the ADCIRC tide model. The tests were done on a global scale as well as on a high resolution San Francisco Bay model. Good model accuracy were achieved for both test cases. The improvement in model accuracy can help to reduce the uncertainty in the tidal datum products for VDatum.