Research and Application News
Africa's ups and downs
08 August 2013
The East African Rift is an area where two tectonic plates are moving apart, making it a region of high geological activity, home to a number of volcanoes.
An animation was recently produced that shows how satellite radars - like the one flown on Envisat - can detect surface displacement with centimetre accuracy from an altitude of about 800 km.
Interferometric Synthetic Aperture Radar - or InSAR - is a remote sensing technique where two or more radar images over the same area are combined to detect slight surface changes between them. Tiny changes on the ground cause changes in the radar signal and lead to rainbow-coloured interference patterns in the combined image, known as a 'SAR interferogram'. These interferograms can then show how land is uplifting or subsiding.
Source: European Space Agency (ESA)