1

I want to run a urbanization model. Required data are;

  • Classified raster data
  • Slope etc.

I've downloaded DEM data from USGS Earth Explorer. Downloaded data are in DTED format. I use EPSG:32636 coordinate system in this project. All satellite imagery are in same coordinate system and pixel sizes are fixed 30m x 30m.(Landsat imagery)

Model wants all data projected into same coordinate system. DEM data was in GCS_WGS_1984 format, I have projected DEM data to EPSG:32636 in ArcGIS and setted output pixel size to 30 meters.

Then I've clipped the data so that it can fit study extent.

The Problem is; After clipping the data I've realized that; number of pixels are not same with the classified satellite imagery. In my slope tif file there are more pixels than the imagery.

I've checked whether satellite image and slope tiff image coincides; enter image description here

They doesn't coincide ?

All satellite imagery pixels coincides but I couldn't understand why slope data doesn't coincides with the satellite image pixels.

PS: I've followed and tried the methods described in these web sites;

  1. https://blogs.esri.com/esri/arcgis/2007/06/12/setting-the-z-factor-parameter-correctly/
  2. https://community.esri.com/thread/23190
  • what was the dem's original resolution? if I'm not mistaken you effectively upscaled your dem by setting the pixel size (i.e. the dem has more but smaller pixels than the landsat imagery in the same extend; by enlargening those, you naturally get a larger result). don't change the pixel size in the reprojection process. instead, use the raster resampling tool afterwards (can't remember the exact tools name in arcgis...don't like arcgis...) – ThingumaBob Jan 13 '18 at 18:39
  • ~30 meters. Which programs can you offer instead of ArcGIS for this kind of purpose ? – Capan Jan 14 '18 at 10:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.