Jpeg to DEM

Question

Hi,

I started off with a jpeg from Google Earth and georeferenced the map in arcGIS using the following process:

How To:  Add a Google Earth Satellite Image Into ArcMap | Introduction to GIS

From here, I would like to create a DEM so i can show contour lines. I know it is possible but can not seem to remember how to do it.

Thanks for your help!!

XanderBakker · Answer

Hi Miranda

I hate to disappoint you, but when you georeference a satellite image in ArcMap, you still do not have the necessary data to generate a Digital Elevation Model. Have a look at this Wiki GIS article: Digital Elevation Model - GIS Wiki | The GIS Encyclopedia or this presentation that I created a while ago on Digital Elevation Models and their applications:Digital Elevation Models - WUR - Grontmij

There are however a lot of free DEM (or LiDAR) resource where you can download DEM data directly. To give you a few pointers:

Digital elevation model - Wikipedia, the free encyclopedia

http://nationalmap.gov/elevation.html

Free Satellite Data - TERRAINMAP Satellite Image Analysis

USGS SDTS format Digital Elevation Model data (DEM)

Lidar Links of Use in Mapping

EarthExplorer

Kind regards, Xander