The image on the left is an Envisat ASAR mosaic of Arctic ice acquired on 23 August 2006. The right image is an EOS Aqua AMSR-E ice concentration acquired on 24 August 2006. There is a significant extent of leads – fractures and openings in the sea-ice cover – just below the pole in both the ASAR image, seen as splashes of dark grey and black, and the AMSR-E image (with British Isles shown for scale), seen by the high concentration of yellow, orange and green colours, signifying low ice concentrations. Credit: Polar View, Leif Toudal Pedersen