[Talk-us] Peaks

Mike Thompson miketho16 at gmail.com
Sat Oct 23 15:46:08 BST 2010


I can't speak in regards to the horizontal error, but in regards to
the vertical error, GNIS elevation is taken from the National
Elevation Dataset (NED).  The NED is a gridded dataset (30 meter
posting I believe), and does not contain spot heights, which is what
you want.  In other words, the NED contains the *average* elevation
for each grid cell, not the peak elevation.

Mike

On Sat, Oct 23, 2010 at 6:52 AM, Nakor <nakor.osm at gmail.com> wrote:
>   Hello,
>
> I was looking at peaks in Glacier National Park. There are quite a few that
> have been imported from GNIS. NPS has also a database of such peaks. My
> issue is that the databases are not consistent. If I take for instance Mt
> Cleveland:
>
>
> GNIS:  48.9250000 , -113.8480556  3175m (10417ft)
> NPS:   48.9227541, -113.8472346   3190m (10466ft)
>
> That's a little bit more than 1/8 mile off horizontal and 50 ft off
> vertical. Is there any other source of information to try and figure out
> what is the correct data?
>
>  Thanks,
>
> N.
>
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