[Aust-NZ] NZ geodata on OSGEO?

[Hamish]

Brent Wood wrote:
> I was wondering about the possibility having OSGEO host an NZ wide
> dataset of topo/cadastral/road centerline/aerial imagery/TLA
> boundaries, EEZ....
> and use it as a demo with OSGEO tools. 
> (probably PostGIS/mapserver/openlayers/geonetwork?).

http://wiki.osgeo.org/wiki/Public_Geospatial_Data_Project

You can look at the Raleigh, North Carolina dataset as a sample of
something already out there,
  http://www.grassbook.org/data_menu3rd.php
  http://www.grassbook.org/ncexternal/index.html


> The advantage we have is that as a small country, a national dataset is
> manageable, in fact smaller than that for some cities (imagery aside).
> It could make a good showcase for OSGEO.

Besides to usefulness to NZers I think we could push it as a test dataset
for general educational courses (anywhere). The size is manageable but
dataset fully featured and the topography is interesting and it is nice
to work with an "entire country's worth" - it's a complete system.


> Is anyone else here able to assist with the development of such a site?

for hosting, if geodata.osgeo.org is not able to provide the
bandwidth/storage space we might try mirror.aarnet.edu.au.
An .nz mirror is of course best.


 
> Assuming we are interested, I figure we may be able to supply the
> following datasets:
> 
> NZTOPO, incl coastlines
> road centrelines

doesn't LINZ's nztopo contain a road_cl layer already?

> national cadastre
> maritime boundaries (fishing areas, reserves, territorial sea & EEZ)
> TLA boundaries
> Electoral boundaries
> LINZ ortho imagery (only 40% coverage- is anything better available?)

the NZMG linz orthophotos downloadable from their website are not, AFAIK
georeferenced. They are broken up by 1:50000 paper topo map code so maybe
they just need a pass with gdal_translate to get them there.

A similar thing with the 300dpi scans of the nautical charts. Those
GeoTiffs have georeferencing info in them, but as far as I've ever been
able to figure out it's bogus. It would be nice to provide those in a
georeferenced form. For the maps I've needed I maintain a little library
of GCPs of the lat/lon grid intersections; NOAA distributes raster scans
of all their charts in BSB format, which is essentially just raw scans
with a list of GCPs pixel coord vs lat/lon coord, again an easy task for
gdal_translate.

(not georectifying or warping maps, just providing GCPs as GeoTiff
metadata)


Also nice to include might be SRTM30+ topo/bathy raster data.

For something higher-res a 10m-50m DEM could be created from the 1:50000
20m contours, height points, coastline, and [offshore] island vector
maps.
I've already done that for the bottom half of the South Island.


Hamish




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