BCTE - Terrace Active Control Station
Last updated on February 11, 2021Click on the red triangle below for the latest station information sheet.
Notice – February 2021
On February 11, 2021, the published Hybrid Ellipsoid Height for BCTE will be updated to a new value that will be 0.040m lower than the old value. New GNSS observations have been made to surrounding passive GCMs in Terrace which revealed a 0.040m incompatibility between the passive network in Terrace and the active control station. By convention, the BC Active Control System has (since inception) been designed to be vertically compatible with CGVD28 heights in the immediate vicinity of each active control station through the use of height transformation models. As a result, published heights of all BCACS stations are actually hybrid ellipsoid heights as opposed to true ellipsoid heights. In the case of BCTE, the model used to derive the published Hybrid Ellipsoid Height is HTv2.0 (1997.0). The updated value will replace the old one which was derived via GPS observations made circa 1998. As a result of this update, end users will arrive at new values that will be compatible with the surrounding nearby passive CGVD28 network.
However, users must also be aware that this will introduce an inconsistency with heights derived using BCTE in recent years. Users are advised to be mindful of this when working with BCTE-derived heights especially for circumstances where agreement with historic projects might be more important than absolute accuracy within the CGVD28 datum.
Warning Bulletin - July 2019
From March 1st at 13:00 PST (21:00 UTC) to July 22nd, 2019 RINEX files for BCTE posted on the BCACS FTP were corrupt. This was initially incorrectly identified as an antenna mast modification; please disregard previous communications which stated this as the cause. An investigation found that no such physical site modifications had been made to this station. Regardless, files during this date range would have yielded erroneous vertical results by ~12cm in magnitude. The magnitude of horizontal error yielded from these corrupt files was found to be near-zero/negligible.
GeoBC advises all users of BCTE to review all projects between those dates to verify whether this error adversely impacted their GNSS-derived results. GeoBC has posted corrected RINEX files onto the BCACS FTP for this date range. Users have the ability to reprocess their GNSS datasets to assess and correct adversely impacted post-processed datasets.