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I am trying to visualize slope for an elevation raster using QGIS terain analysis tool. The results are no what I would expect.

Elevation raster is from NASA's SRTM program. I picked a relatively mountainous region to run a test N39W121.

elevation model looks like this

enter image description here

but resulting slope raster only has two values 0 and 89.9 . enter image description here

I used default setting's in QGIS' DEM tool, set to slope mode. Can anyone help me firgure out what I'm doing wrong. Is it a problem with the original data, or is it settings? I am at a loss. Calculating hillshade and ruggedness index with the same tool produced results as expected

user3750486
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1 Answers1

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By default, SRTM's map horizaontal units are in degrees (WGS84), where the vertical units for SRTM is in meters. This either needs to be compensated for in QGIS's DEM analysis settings or the SRTM raster needs to be converted to a projection that uses meters for its map units.

user3597565
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