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tilezen / joerd

Joerd can be used to download, merge and generate tiles from digital elevation data
MIT License
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vertical datum? #130

Closed DarkForceOne closed 7 years ago

DarkForceOne commented 7 years ago

What is the vertical datum of the elevation data?

zerebubuth commented 7 years ago

It should be the WGS84 nominal sea level, but there may be deviations from that depending on which dataset provided the samples in question. Does that help?

DarkForceOne commented 7 years ago

Yes, it does answer my question.

I have seen some projects related to seawater intrusion where a few feet (decimeters) is critical. Since we often compare elevation data from different sources, a standardized vertical datum would allow users to convert the data to the same standard before comparing them.

It would be great to clearly define and use a standardized vertical datum. Many thanks!