Hurricane Ike tracked by ESA’s Envisat   Thanks to Envisat’s unique capability to acquire optical and radar imagery over the same area of the Earth simultaneously, the top and bottom of a hurricane can be viewed at the same time. This unique view of Hurricane Ike is an example of combined optical MERIS and radar ASAR images, acquired on 9 September 2008 and showing the swirling cloud-tops and the shape of the wind-driven sea surface.   Sea surface roughness map over Cuba, acquired on 9 September 2008 by Envisat's ASAR instrument and processed in near-real time. The eye of Hurricane Ike is centred over Cuba island.   Around the eye of the storm, the sea surface velocities also capture the circular direction of the prevailing wind and waves, as visible in this wind speed map of Hurricane Ike over Great Inagua Island in the Bahamas on 7 September 2008.   A map of the radial component of sea surface velocity over Cuba island, produced in near-real time from Envisat's ASAR data acquired on 9 September 2008. Release date: 28 February 2012