Education: VDatum Standard Procedures

The final product produced by this process is the selection and definition of the geographic region for which the VDatum data sets will be developed or revised.

1. Reception of requests: The VDatum MT and TT will collect, archive and report on (as needed) the reception of requests from user groups, NOAA's partners and other interested parties.
2. Establishment of priority of requests: The VDatum MT will decide or approve the specific location where VDatum is to be developed, taking into account available funding, Congressional incentive, user requests, potential partnerships, and/or other criteria.
3. Assessment of requirements and resource needs: With the approval of the VDatum MT, the VDatum TT will:
   
   • assess their resources to determine whether personnel are available and when the project can be scheduled
   • the assessment will also include the possibility of updating existing VDatum transformation grids from adjacent, overlapping or included regions
   • the results of the assessment will be reported to the VDatum MT, and a determination of project feasibility will be made by the MT.
4. Coordination among OCS, NGS, CO-OPS and other partners: Once approval has been gained, the VDatum TT will:
   
   • discuss the project requirements and assign tasks as necessary with the NOS partners
   • notify relevant external partners (PMEL, USGS, USACE, etc.) of the plans
   Final plans will incorporate comments from partners and management.

The final product produced by this process is a set of transformation grid files, consisting of six tidal transformation grid files and a topography of the sea surface (TSS) transformation grid.

This process is broken down to five major procedures below:

1. Data Acquisition: establishing geographic limits; collecting digital shoreline data, bathymetric data, tidal datums and associated water level data, benchmark data, previous hydrodynamic model results, and data quality assessment.
2. Tidal Datum Modeling: selection of specific area; selection of method to be used for tidal datum modeling; application of method of spatial interpolation; application of method of harmonic constants; application of method of hydrodynamic modeling and error analysis.
3. Creation of the Tidal Datum Transformation Grids: creation of a marine grid; creation of the tidal datum transformation grids and error analysis.
4. Generation of the Topography of Sea Surface (TSS) Transformation Grids
5. Quality Control and Archival

The final product of this process is a functioning VDatum web page which allows the users to access VDatum for a newly developed or revised region. NGS/RSD maintains the VDatum website, acting in coordination with OCS/CSDL and CO-OPS.

The product of this process is a set of updated VDatum transformation grids for a particular region.

1. Track changes in tidal data: on monthly basis, CO-OPS tidal datum and harmonic constants data are monitored and saved in a database (such as TideSheet).
2. Periodic review: on a periodic basis, or in response to user comments, or when significant changes in data occur, the VDatum TT will assess the impact on such changes. If the potential change is great, or when significant errors can be corrected, the VDatum TT will make recommendation to the VDatum MT. Then the process V01 can begin.

The product of this process is improved methodology for, and application of, VDatum transformation grids and VDatum software.

1. Improve tide and/or datum models: the VDatum TT will continually assess the accuracy and efficiency of its tide and datum models and will incorporate improvements as they become available. This activity may lead to the initiation of Process V04.
2. Adaptation of models for other regions/purposes: the VDatum TT will continually assess models and data sets produced by outside organizations with the goal of adapting completed results to the VDatum project. This activity may lead to the initiation of Process V04.
3. Data delivery services: the VDatum TT will continually assess its data delivery services and will strive to make data more accessible. The VDatum TT will investigate updates, developments, and enhancements to the VDatum software. 
4. Contact with potential partners: the VDatum TT will seek out new partners from other agencies or geographic areas with the intent of increasing awareness of our products and supporting the missions of other agencies.
5. Reports on technical work: the VDatum TT will disseminate technical reports on its achievements and will make presentations at scientific meetings to increase awareness and improve it techniques.