Arctic Ocean swirls

This Envisat image, acquired 14 June 2008, captures the marginal ice zone of the Greenland Sea during the onset of spring melting. The bright white swirls at the ice edge are traced out by brash ice – small sea-ice fragments of ice floes that have been broken up by waves. Larger ice floes can be spotted drifting southwards in the East Greenland Current, which flows southward along the eastern coast of Greenland (visible running down image left). Swirls indicate drift of the small pieces of ice in response to ocean vortexes, or ‘eddies’, and are an expression of the ocean surface currents. The myriad of swirls show how dynamic the upper ocean is at this time of year because of strong gradients in temperature and salinity.