UTM-Projection Problems

[Jason Sperfslage]

> Hi to all
> I have to set up a Region with GRASS5.0b consisting of UTM coordinates of
> the Zone 37. The trouble is, that my coordinates are spanning from the
> northern hemisphere to the southern hemisphere (Latitude).
> The northern edge is at: 99499.47 (Zone37N 0:53:56.61767N) and my southern
> edge is at 9949706 (Zone37M, 0:27:17.878704S).
> 
> My question is: Does GRASS support two UTM zones?
> Or do I have to shift my whole region for about 100km north in order to get
> rid of the UTM change at the equator?
  
  
You might decide to reference everything to the Southern hemishpere, then let
areas in the Northern hemisphere simply stretch beyond the 10,000,000 limit at
the equator.  In the end, you would merely add 10,000,000 to each of your 
northings in the Northern hemisphere.  This has been sufficient for some of our
needs in the past, and GRASS seems to deal with it easily. 

Hope that helps.

Jason

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