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<div style="margin-top:0; margin-bottom:0">Greetings,</div>
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<div style="margin-top:0; margin-bottom:0"><span>I would appreciate any ideas or resources on how to critically assess assigning projections to data sets
<span>when ambiguous or missing metadata make it difficult to identify a "correct" projection. It seems projections that are incorrect, but functionally useful, are regularly assigned by informal convention.</span></span><br>
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<div style="margin-top:0; margin-bottom:0">I am working with National Water Information System station locations (USGS). The lat/long coordinates reference NAD83 datum. Where altitude is available, it references NGVD29, NAVD88, or COE1912 datum. However, no
initial projection is specified. USGS representatives tell me there has never been a formal mapping between USGS geodetic datums and EPSG. Individuals have made cases suggesting EPSG 4269 and EPSG 7406 should be reasonable, but these seem to be informal usages
and/or conventions. After trying both, they seem to produce equivalent maps. <br>
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<div style="margin-top:0; margin-bottom:0">I am working on a corridor that runs between the northern and southern borders of the US.
<span>I would expect that distortions are not negligible at that scale, but perhaps I'm wrong?</span></div>
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<div style="margin-top:0; margin-bottom:0">You can <a href="https://drive.google.com/drive/folders/1WWpAFTo_9mUKKPR8WB7hpWyAfPtQDVtP?usp=sharing" target="_blank" rel="noopener noreferrer">
find code and a subset of data here</a>.</div>
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<div style="margin-top:0; margin-bottom:0">Thanks,</div>
<div style="margin-top:0; margin-bottom:0">Kate Thompson<br>
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