[PROJ] Static/Dynamic Webmapping Problem version 2.0

[Cameron Shorter]

I'm a little nervous that I've overwhelmed people by the number of pages
I've used to describe the web-mapping misaligned maps problem.

The key message I'm hoping to get feedback on is:

* We are currently using the dynamic WGS84 datum as if it were a static
datum (locked to a different epoch in different regions).
* This appears to be suitable for current web mapping requirements.
* Realigning static and dynamic datums (as started by Australia, with
others to follow) is tripping a map misalignment problem.

Proposed solution:
* Define an EPSG code which describes current practice of a static datum,
which is fixed to different epochs in different regions.
* Move to using the new EPSG code in web-mapping.

Question to techies:
* Is it technically possible to create a reference frame realisation
(datum) which is fixed to different epochs in different regions?

Warm regards, Cameron

On Fri, 12 Jul 2019 at 22:32, Cameron Shorter <cameron.shorter at gmail.com>
wrote:

> Hi folks,
> I've incorporated a lot of feeback from people on this list, and from the
> Australian geospatial people and have restarted the Static/Dynamic
> Webmapping Problem.
>
> Comments are encouraged.
>
> If commenting, please log so we know who says what. Please don't change
> the text as it quickly becomes difficult to read.
>
> I'm very mindful that this is a challenging problem, requiring
> collaboration to solve, and we still have quite a bit of work in achieving
> this.
>
> Doc here:
>
> https://docs.google.com/document/d/1A4Q8-863fKQ-BJzh0ruz7bKvk3itiy8LmmWrwUR1J9g/edit#heading=h.nn4r38g65fhf
>
> Original problem statement:
>
> >* > Our Australian spatial data users are about to face a systematic mismatch **challenge when trying to use multiple static datums (GDA2020, GDA94) with **the dynamic datum (WGS84). At the moment, it is government agencies** grappling with the problem, but it is about to become a mainstream issue.*
>
> Cheers, Cameron
>
>
> --
> Cameron Shorter
> Technology Demystifier
> Open Technologies and Geospatial Consultant
>
> M +61 (0) 419 142 254
>
>
>
>

-- 
Cameron Shorter
Technology Demystifier
Open Technologies and Geospatial Consultant

M +61 (0) 419 142 254
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