Tide Modeling in Support of NOAA's National VDatum Program

NOAA's National Ocean Service (NOS) has developed the VDatum software to allow users the ability to easily transform vertical elevation data among tidal, orthometric, and ellipsoid-based 3D reference systems, VDatum applications are developed on a regional basis with the goal of attaining seamless coverage for all U.S. near-coastal waters. Development of VDatum is coordinated among three NOS offices: the Coast Survey Development Laboratory (CSDL), the National Geodetic Survey (NOS), and the Center for Operational Oceanographic Products and Services (CO-OPS). As part of this collaborai ion, CSDL develops the tidal datum fields used as input to the VDatum software. This paper describes the standard modeling procedures CSDL uses to develop the tidal datum fields, how these are built into the VDatum framework of vertical datum transformations, and the community modeling framework that is envisioned for VDatum-derived models and products.