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From: Frank Reed (no email)
Date: Tue Dec 09 2003 - 16:02:24 EST
Fredrik wrote:
"I've found this GLOBE project from a web search, which offers free
"30-arc-second (1-km) gridded, quality-controlled global Digital
Elevation Model (DEM)" data."
That was the best you could get until this year.
GLOBE and the similar product GTOPO30 were based on traditional mapping and
elevation resources (scanned maps). They had numerous errors and
inconsistencies. They have been superceded by data from one of the most important space
shuttle missions ever --the shuttle radar topography mission. A version of this
data set was released just a few months ago. Search for SRTM30 to read more
about it.
If you go to my web site and click on the link at the very bottom on the left
that says "Waterworld", you'll see one use for this sort of data, though I
don't think it has much relevance to marine navigation.
Frank E. Reed
[ ] Mystic, Connecticut
[X] Chicago, Illinois
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