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DEM with a vertical datum other than NAVD88

Started by j_silver, November 15, 2012, 07:06:06 PM

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Hi  -

My group is trying to run SLAMM in Belize.
We only have the ASTER GDEMv2, a global DEM.
It may be that the vertical accuracy is too coarse, however the system is primarily mangroves, so there are not that many habitat conversions that we need to be able to capture.

In any case, we are having trouble converting the vertical datum from EGM96 to NAVD88.
I know this is a long shot, but does the model have the capacity to be run using a DEM with a datum other than NAVD88, and the corresponding VDatum correction?
(Alternatively, if anyone has had success converting between those two datums, tips would be greatly appreciated - I think the NOAA VDatum conversion program only works in the USA).

Thanks,  Jess

Jonathan S. Clough

Ultimately SLAMM Requires elevation data to be on an MTL basis.  For the majority of our work our elevation data is delivered in the NAVD88 format.  Therefore we have a parameter (fixed or raster) to convert NAVD88 to MTL. 

Using a different vertical datum is no problem.  Either convert the data to an MTL basis with GIS beforehand (set the MTL-NAVD88 parameter to zero) or replace the "NAVD88" in the "MTL - NAVD88" parameter with {your datum} i.e. "MTL minus {your datum}". 

Note there is some guidance regarding how to populate the parameter that converts from NAVD88 (or "your datum") to MTL here.