The Intergovernmental Committee on Surveying and Mapping (ICSM) is pleased to partner with the Surveying and Spatial Sciences Institute (SSSI) Young Professionals to present a four part lunchtime webinar series on upgrades to the Australian Geospatial Reference System (AGRS); the collection of datums, reference frames, models, infrastructure and standards needed for accurate 4D positioning.
Part 1: Upgrading the Australian Geospatial Reference System
Wednesday 21 August 2019
The Australian Government has committed $225m to Geoscience Australia to provide 5-10 cm accurate positioning to anyone, anytime, anywhere in Australia by 2023. This is a significant improvement from the 5-10 m accuracy you can currently achieve using GPS enabled devices.
In anticipation for the growing use and reliance on positioning technology, the Intergovernmental Committee on Surveying and Mapping’s Permanent Committee on Geodesy (ICSM PCG) is leading the upgrade of a number of elements of Australia’s Geospatial Reference System to ensure Australian’s can maximise the benefits of precise positioning. The elements of the Australian Geospatial Reference Systems being upgraded include:
- static datum (from GDA94 to GDA2020)
- introduction of a time dependent reference frame (Australian Terrestrial Reference Frame)
- introduction of a new reference surface for heights (Australian Vertical Working Surface)
- improved geodetic infrastructure, and
- standards development to improve access and efficiency of geodetic data.
This first of four webinars on the Upgrading the Australian Geospatial Reference System addressed questions like:
- What is Geodesy?
- What is the Geoscience Australia precise positioning program?
- What is the Australian Geospatial Reference System?
- What parts of the Australian Geospatial Reference System are being upgraded and why?
Part 2: Geocentric Datum of Australia 2020
Monday 9 September 2019
This webinar looked at some of the problems with the static datum, GDA94, and why it was no longer fit for purpose for some users. We also explained how the new static datum, GDA2020, was developed and provided an overview of the tools and products available to help implement GDA2020. This includes information about the GDA94 to GDA2020 transformation parameters, transformation grids, online tools, fact sheets, technical manuals and the AUSGeoid2020 model to convert GDA2020 ellipsoidal heights to Australian Height Datum heights.
Part 3: Australian Terrestrial Reference Frame
Monday 21 October 2019
Part 3 took things further and explained why Australia is introducing a time dependent reference frame; that is, a datum in which the coordinates of features will change with time due to the motion of the Australian tectonic plate (7 cm/yr). We described how the choice of using GDA2020 (static) and ATRF (time-dependent) will be left up to the user and will dependent on the task. We discussed the emerging user base that need time dependent coordinates and the important role spatial professionals will play in providing end users with accurate positions. Finally we described how the International Terrestrial Reference Frame, Australian Terrestrial Reference Frame and GDA2020 are linked.
Part 4: Height: Ellipsoid, geoid, Australian Height Datum and Australian Vertical Working Surface
Thursday 28 November 2019
The final part of the series provided an introduction to height transfer, ellipsoids, geoid, the Australian Height Datum (AHD) and the development of AUSGeoid2020. Furthermore, we introduced a new reference surface for heights in Australia; the Australian Vertical Working Surface (AVWS). We described how and when AVWS can be used and the benefits compared to AHD.