ESA Portal - Focus On - Vanishing valleys and misleading maps: why the world is now a different shape

Media Centre

Press Releases ESA Television Launch Media Corner Exhibitions

Services

Publications Frequently asked questions ESA-sponsored Conferences Help Site Credits Portal terms of use Comments Subscribe

Vanishing valleys and misleading maps: why the world is now a different shape

16 October 2000

Back to article

Have you ever spotted this shape on world maps? You will now ...
It’s a sheer sided valley in the Sudan 3 x 3 degrees across and over 150 m deep !

Fly over it with the ERS-1 altimeter and you only see flat desert.

Comparing the GDEMs with the altimeter heights shows that the whole feature does not exist.

Images: DEM team at De Montfort university, Leicester(PI: Philippa Berry)

Back to article

The world's most spectacular tourist site?

A series of spectacular waterfalls in the Amazon basin cascade over undiscovered cliffs over 2000 km long! (left image, GDEM data)
The altimeter map (right) shows the real Amazon, with its intricate network of interlocking rivers and tributary streams … but no amazing cliffs!
Images: DEM team at De Montfort university, Leicester.

Back to article

The Great Wall of the Western Sahara - a 200 m high "wall" runs for over 200 km across the western Sahara, where DCW and DTED meet. This is caused by a 200 m contour interval in the DCW data. The altimeter shows the actual surface.

Images: DEM team at De Montfort university, Leicester.