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Does anyone know whether Google Maps Elevation data removed buildings, trees and other non-terrain related structures from its elevation data?

I checked their pages, but couldn't find an answer to this question.

There is an article which mentions the sources which Google Maps Elevation is using: SRTM, GLOBE and some LIDAR raster data.

But still I couldn't find information whether they additionally altered their raster data, so that buildings and other non-terrain related structures are removed.

  • I'm not sure the horizontal and vertical accuracy of the SRTM data (20m horizontal see here) and GLOBE (1km horizontal) datasets would really warrant controlling for non-terrain structures, unless you were working in an urban area (maybe?). LiDAR is typically provided in Bare Earth format with vegetation and structures removed (at least it is when I get it), so I would imagine any Google Maps area with LiDAR coverage would be the same. – Carl Dec 15 '16 at 17:24
  • @Carolyn thank you for the reply! Is there a page where can I read more about Bare Earth LIDAR Google Maps Elevation format having vegetation and structures removed? – marco Dec 15 '16 at 23:26
  • Not that I can find, no, but I know that bare earth is generally considered more useful than highest return, and so that's what is usually available. Note that data from different places will be from different sources, so you need to check the metadata for that specific area. However, I don't know of any way to get metadata out of google earth (which seems crazy to me.) – Carl Dec 16 '16 at 16:44
  • There is this post by someone in Portland, OR. You can also get data from OpenTopography, which has better referencing than googleearth, and is probably getting data from the same sources as googleearth. – Carl Dec 16 '16 at 16:44
  • Thank you @Carolyn. So when you say: "Bare Earth LIDAR Google Maps Elevation format has vegetation and structures removed", this is from your own personal experience of working with Google Maps Elevation data? Can you just elaborate on why OpenTopography has better referencing than GoogleEarth? I am aware of that article by someone from Portland. I posted in the initial upper post. – marco Dec 16 '16 at 18:32
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The LiDAR data that GoogleEarth is using is patched together from a variety of open data sources. In order to say for sure whether you are using bare-earth elevation data, you would need to know which data set you were using and how it has been processed. Unfortunately, there doesn't seem to be any way to find a source for elevation data within GoogleEarth.

OpenTopography lets you download specific datasets with full metadata, so if you can find the same data on that site, that would be one solution to your problem.

In my experience, however, bare-earth DEMs are generally considered to be the most useful end product of a LiDAR point cloud - it is nearly always provided as a deliverable when LiDAR data is purchased - so I would say it is likely that all the LiDAR data in Google Earth is from bare-earth DEMs.

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I have a house in Southwest Florida, which is very flat and close to sea level, and where homeowners know the elevation of their property very accurately. It's clear that the elevation shown by Google earth includes the height of the roof at various spots on the house, and includes a fairly accurate measure of some tall trees behind the house.

  • This sounds plausible. Are you able to back this up with some evidence? – Martin Hügi Oct 1 '17 at 18:31
  • Yes, I have a couple of screen shots showing Google Earth elevation, one at the top of a tree, and the other right next to the tree. I'd post them them here if I knew how, or I can email them to you. hank.jakiela@gmail.com – Hank Jakiela Nov 8 '17 at 17:07
  • You can edit your answer and add them to it. Use the 'image' icon – Martin Hügi Nov 8 '17 at 17:39

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