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Converting from Mean Sea level to ground elevation.

December 01 2008 | 0 comments
Categories: Map Data

ESRI used to have an excellent document detailing how you convert a feature class from MSL to ground elevation. I have a series of polygons that I need to convert from MSL to ground elevation so I can recalculate their acreages. If you can point me to literature detailing how to do this I would certainly appreciate it.


John C.

Mapping Center Answer:

We haven't been able to identify what document you might be referring to - sorry.  If you do locate it, be sure to let us know!  

However, normally, to move data from MSL to local ground elevation, you cn multiply all the x,y coords by a scale factor. You can do this by reprojecting the data and including the scale factor into the output coordinate system. You could then calculate the areas. The other method is to calculate the areas in the "base" coordinate system, and then scale the areas by the square of the scale factor.

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