Elevation: The Foundation Layer Every Terrain Analysis Starts From
Every slope, watershed and viewshed you will ever compute traces back to one raster: elevation. A Digital Elevation Model records the height of the land at each pixel, and its quality quietly sets the ceiling on everything derived from it.
How it reads the surface
A DEM stores height above a reference datum (often a geoid such as EGM96) per cell. Global DEMs like SRTM and the Copernicus DEM are built from radar or stereo imagery; their vertical accuracy and resolution determine how faithfully every downstream product reflects reality.
The formula
Reading the values
An absolute height value; interpretation is site-specific (sea level, valley floor, ridge line, etc.).
The data it needs
| Derived from | Digital Elevation Model (SRTM / Copernicus, 30 m) — not an optical band index. |
In practice
Elevation itself drives flood-risk zoning, infrastructure and route planning, and climate and ecological modelling, and it is the input to slope, aspect, hillshade and hydrological analysis.
Where it struggles
Know your DEM's limits: SRTM is a surface model, so it includes tree canopy and building height, and it carries voids in steep terrain. For precise work, choose a DEM whose resolution and vintage match your question.
Compute Elevation on your own study area
Skip the code. Draw or upload a boundary and Spatial Research Suite runs Elevation on live data — with cloud masking, exports and citations built in.
Run this analysis in GISforus →Frequently asked
What is the difference between a DEM, DSM and DTM?
A DEM is the general term for a gridded elevation surface; a DSM includes surface features (canopy, buildings) while a DTM represents bare earth. SRTM behaves like a DSM.
How accurate is SRTM elevation?
Roughly ±16 m vertical for the global product, with voids in steep terrain — adequate for regional work but not fine engineering.