SeaSAR 2006: Satellite radar reveals ever-changing face of the ocean

Radar satellites such as ESA's Envisat and ERS-2 maintain constant watch on
Earth's surface, their signals able to cut through clouds, rain or darkness.

This surveillance extends beyond the land to the 71% of the planet covered by
ocean – acquiring unique imagery of the ever-shifting face of the sea that is
proving a boon to oceanographers.

Read more at:

http://www.esa.int/esaEO/SEMGMCNZCIE_economy_0.html