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Is there a way to look up elevation data with latitude and longitude data?


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Since most devices cannot accurately measure elevation, even with a barometric altimeter, I'm wondering if there are any websites out there with accurate elevation data? If so, can I simply punch in the latitude and longitude to obtain to elevation data for anywhere on Earth?

 

As a GSAK user I have elevation for almost all caches in my databases. The info is imported from an external source automatically. For mysteries, altitude is for the bogus coordinates as the altitude for corrected coordinates could be a hint in solving the puzzles.

 

I don't know how accurate altitude is in Google Earth but that may work too.

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If it's accuracy you're looking for, I'm pretty sure your best results will come from GPS altitude. (Barring professional survey equipment.) I know, not as accurate as horizontal position, but still pretty decent. Barometric altimeter won't be as accurate, and neither will the web services you're looking for; I believe the latter get altitude from stereoscopic imagery. Topo maps, even less accurate.

 

Of course, the web services are handy if you're not at the location to take a GPS reading.

 

The times I needed to know a cache altitude (eg. my highest), I just interpolated from a topo map. Good 'nuff for me.

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Since most devices cannot accurately measure elevation, even with a barometric altimeter

 

What do you mean by "accurately?" In decent conditions with WAAS a handheld can measure it to a precision of about 5 meters or so. The bias is essentially zero so the accuracy is approximately equal to the precision.

 

I'm wondering if there are any websites out there with accurate elevation data? If so, can I simply punch in the latitude and longitude to obtain to elevation data for anywhere on Earth?

 

You mean "precise" instead of "accurate," I think.

 

Yes, there are Web services that you can use. The accuracy and precision are complicated to unwind, as the most comprehensive are derived from satellite data that has been averaged over some area.

 

For the continental US, the best is probably the USGS National Elevation Database (NED) Web service. Here is a query for N 37 00.000, W 122 00.000:

 

http://ned.usgs.gov/epqs/pqs.php?x=37.0&y=-122.0&units=Meters&output=xml

 

Notice that the results come as XML.

 

Google has a service, which uses a proprietary elevation model. Here is the same query as a Google one:

 

http://maps.google.com/maps/api/elevation/xml?locations=37.0,-122.0&sensor=false

 

Geonames.org can get you Aster or SRTM3 data, which is lower-resolution. All of these are Web services, like the above.

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