[CAP] Geospatial Elements

[Bob Bunge]

NOAA's National Weather Service (and I assume most other US Govt 
agencies) is starting to standardize to the current US Federal standards 
of the North American Datum of 1983 (NAD83) for horizontal positioning 
and the North American Vertical Datum of 1988 (NAVD88) for elevation 
values, which  together are known as the National Spatial Reference 
System (NSRS).

NOAAs National Geodetic Survey (NGS) is the federal agency responsible 
for the specification and maintenance of the NSRS.

Is this a need?  I'm not a geospatial datum expert (I'm told there isn't 
that much difference between the two and other uncertainties are likely 
much larger when it comes to horizontal products like tornado warnings) 
so I can't say for sure at this time.

Bob Bunge
NWS

Mick Jagger wrote:
> Hi,
> 	A number of posts have mentioned changing CAP's geospatial elements to use GML.  I think a clarification needs to be made about whether the posters are talking about full-monty GML, or a custom CAP profile akin to Simple.  To me the question boils down to whether different Coordinate Reference Systems need to be available to CAP.  Anybody have a need for something other than WGS84?