Not all ice is created equal: this view of the Amundsen Gulf has open ocean, older thick ice, young thin ice, fresh snow and even broken brash ice adrift at sea.
Top image: Ice in the Amundsen Gulf on June 21, 2014. Credit: NASA
This chunk of ice is along the Amundsen Gulf, the westernmost edge of the fabled Northern Passage. The gulf is located between Victoria Island and Canada's mainland. It is particularly interesting for the variety of ice present in a single photograph: fresh snow, shards of broken ice, older stable ice, and fragile year-old ice.
Ice in the Amundsen Gulf between Victoria Island and Canada's mainland, with the Beaufort sea to the west. on June 21, 2014. Image credit: NASA
The blue ice is the oldest ice in this view, hard, thick sheets with few small air pockets. The light grey ice is younger and thinner, formed just this winter and anywhere from 30 centimeters to 2 meters thick. The darkest grey ice is younger yet, freshly-frozen or refrozen. Out in the dark black of open ocean is brash ice, the broken shards and burgs of all ice types shed into the seas. Over it all is the bright white of fresh snow, uncompacted and full of air pockets.
Ice types in the on the westermost edge of the Nortwest passage on the first day of summer. Image credit: NASA
While ice extent each year is fluctuating, the old, stable sheets of sea ice are thinning and shrinking, disrupting the local ecosystem. While the Northwest Passage was still frozen when the summer melt season ended in September, 2014 was the sixth-lowest ice extent since satellites began measuring ice coverage. Scientists also spotted open water stretching farther north than ever before, reaching 85° north in the Laptev Sea north of Siberia.
Ice extent on at the end of the summer melt season on September 17, 2014. Image credit: NASA
This image of sea ice in the Amundsen Gulf was captured by the Operational Land Imager on the Landsat 8 satellite as part of a continuous, unbroken swath over the Arctic on the first day of summer in 2014. The entire flyover covered a 200-kilometer (120-mile) wide ban about 6,800 kilometers (4,200 miles) long from Sweden and Finland, across Greenland and into western Canada.
Landsat 8 imaged a 200-kilometer wide band across 6,800 kilometers of the Arctic on June 21, 2014. Image credit: NASA