The video is an animation of daily Arctic sea ice extent this summer, as seen from satellites.
This year’s minimum sea ice extent was 622,000 square miles above the record minimum extent, which occurred in 2012. That year, both the Northern Sea Route and the Northwest Passage were open to shipping.
This year, the Northern Sea Route (also referred to as the Northeast Passage), which tracks through the Arctic along the Russian Arctic coast, has been open to shipping for the past month or so. On the other side of the Arctic, the Northwest Passage did not open this year, and will remain closed through the rest of 2014.
Meanwhile, in the Antarctic, sea ice has remained at record high daily levels for most of the year. It’s still too soon to say what the maximum sea ice extent will be this year in the southern hemisphere.