Geoid Model Data

Geoid models contribute to the vertical component of the B.C. geospatial reference system so that ellipsoidal Global Navigation Satellite System (GNSS) heights can be converted to orthometric elevations.

***For CGG2013 geoid models, please visit the NRCAN Geoid Models website.***

In British Columbia, CGVD28 is the current vertical datum. Users require the HTv2.0 height transformation model to convert ellipsoidal elevations to approximate CGVD28 elevations. Geoid models are roughly equivalent to mean sea level plus the natural continuation of mean sea level under the landmass. This extension must be modelled or determined mathematically. Geoid models provide the difference between the ellipsoid and the geoid. This difference is known as geoid-ellipsoid separation, or geoidal height.

A geoid model allows the user to compute orthometric elevations using GNSS technology anywhere across the country.

Height Transformation Model (Hybrid Geoid Model) for CGVD28 - Metro Vancouver Version

For CGVD28, a  hybrid geoid model that covers all of Metro Vancouver (MV), Abbotsford and east to Hope is available for download. This hybrid geoid model is an enhanced version of HTv2.0. It has been loaded into Management of Survey Control Operations & Tasks (MASCOT) for all geodetic control monuments in MV, ensuring that MASCOT and the Metro Vancouver Real Time Network are compatible.

The official name of this hybrid geoid model is HTMVBC00. It has been renamed to  differentiate it from HTGVRDBC00. This model is equivalent to HTGVRDBC00, except it is extended to the east to provide coverage for Abbotsford:

The BYN file above can be directly imported into GPS software. Natural Resources Canada provides GPS-H, a tool that can view and extract geoid values from BYN files.

The HTGVRDBC00 hybrid geoid model is also provided below. As previously mentioned, it is the same as HTMVBC00 except that it does not provide hybrid geoid-ellipsoid separations east of the Township of Langley.