CartoDEM
Topic: Topographical Maps: Relief Representation and Interpretation · NCERT: Beyond NCERT
Meaning
CartoDEM is a digital elevation model (DEM) of India made by ISRO-NRSC. A DEM is a grid of ground heights stored on a computer. CartoDEM was built from stereo images of the Cartosat-1 satellite. Stereo images are pairs of pictures of the same place taken from two angles, which allow heights to be worked out. It is free to download at about 30 m resolution on ISRO's Bhuvan portal. A GIS can use it to work out slope, drainage, watersheds and flood zones.
Example
A planner mapping landslide-prone slopes in Uttarakhand can download CartoDEM from Bhuvan. A GIS then turns it into a slope map that shows the steepest, most risky ground.
Don't confuse with
- SRTM: this is NASA's near-global DEM, made with radar from the Space Shuttle in 2000. CartoDEM is ISRO's DEM of India, made from Cartosat-1 stereo images.