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Just wondering if anyone knows when and how to do the transition to GDA2020 in QGIS? I assume it will be as simple as selecting the CRS but it doesn't appear to be available as a CRS yet. Currently using QGIS 2.14.3 - Essen.

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QGIS depends on GDAL for a lot of its spatial data management. GDAL 2.2.0 should include GDA2020, as it includes updates for EPSG 8.9 and EPSG 9 (see https://trac.osgeo.org/gdal/query?group=status&milestone=2.2.0 ), for which the GDAL ticket says, "This release includes some critical changes for Australian users."

EPSG 9 "What's New" page says, "New data for Australia" (see http://www.epsg.org/EPSGDataset/WhatIsNew.aspx ). It's unclear if this means GDA2020, but I would guess so. I've not yet found where to confirm this, however. In any case, GDA2020 is certainly in the current EPSG registry.

It's unclear when GDAL 2.2.0 will be released, as they don't include dates on their versions roadmap, but my guess would be after 2.1.4 which is also on the roadmap, but not yet released. So 2.1.4 is probably "real soon now" and 2.2.0 sometime after that. I would guess that 2.2.0 would be out some time late this year. But nobody really knows, at this point.

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    GDAL 2.1.3 was only released about 3 weeks ago. 2.1.4 might be a couple of months away. Ticket for EPSG 9.0 is trac.osgeo.org/gdal/ticket/6772 – user2856 Feb 13 '17 at 0:59
  • Thanks - makes sense. I've revised my guess for 2.2.0 to "late this year", but just a guess of course. – Son of a Beach Feb 13 '17 at 1:06
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    I can confirm that epsg v9 does include all the STATIC gda2020 reference systems. The dynamic ones are a different story - there's no specification available for these yet and all the libraries will need complex changes to account for CRS with temporal factors. – ndawson Feb 13 '17 at 21:59
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Adding to answer by Alex Leith, the “definition” of the GDA2020 datum has been added to the EPSG registry and EPSG “Datum” codes added. See http://www.ga.gov.au/scientific-topics/positioning-navigation/datum-modernisation for a summary of the codes.

However, the information about how to transform between GDA94 and GDA2020 – by either a 7 parameter similarity transformation (using towgs84 in PROJ.4) or the preferred method of an NTv2 grid (using nadgrids in PROJ.4) hasn’t been added to EPSG registry (transformation codes defined, not datum codes) because (as I write this) neither have been released yet.

So, they aren’t in any software and practically, you can’t use GDA2020 right at this moment.

It will be communicated when the transformations are defined on the above site.

Also if you are interested in receiving the latest advice and assistance recommend you join the new GDA2020 forum http://gda2020.invisionzone.com/

As Alex notes, he is work undertaking some work to arrange for inclusion of appropriate transformations tools in QGIS and the Australian QGIS users group will be advised when there is more information.

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To add to the answer of Son of a Beach, the definitions of GDA2020 CRSs have been added to EPSG, and these have been brought into Proj4 and GDAL. These CRS definitions are good enough for many uses, but to do a precise transformation, you need to use a NTv2 transformation grid.

While you can currently manually add the grid transformation file (GSB files), I am currently working with ICSM to build Australian transformation support into the NaturalGIS NTv2 Plugin. This work is nearly complete.

We are also building a stand-alone ICSM plugin to do Australian transformations using NtV2 grids.

In addition to this, we are looking into how we can encourage the default inclusion of these grids in open source software, including Proj4 and GDAL, which presumably flows through to QGIS.

If anybody would like to assist in testing these plugins, please get in touch. If there's anything I can do to encourage getting the GSB files and precise transformations into open source software, also please get in touch!

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