One reason for the low sea ice extent is the high and rising temperature of the Arctic Ocean. On October 27, 2016, the Arctic Ocean was as warm as 14.8°C or 58.6°F (green circle near Svalbard), 12.1°C or 21.7°F warmer than 1981-2011, as the image below shows.
As the sea ice shrinks, less sunlight gets reflected back into space, while more open water and higher sea surface temperatures also cause storms and cyclones to become stronger. Stronger cyclones also cause greater amounts of water vapor to move up the Pacific Ocean and the Atlantic Ocean toward the Arctic.
As the images show, temperature anomalies in many places are at the top end of the scale, i.e. 20°C or 36°F. Rising temperatures over the Arctic further contribute to a rise in the amount of water vapor in the air over the Arctic at a rate of 7% more water vapor for every 1°C warming. Since water vapor is a potent greenhouse gas, more water vapor further accelerates warming in the Arctic.
Another danger is that, as the Arctic Ocean gets warmer, more methane will erupt from destabilizing hydrates at its seafloor. Ominously, high methane levels are visible over the Arctic on above image, showing methane levels as high as 2424 ppb on October 24, 2016.
The situation is dire and calls for comprehensive and effective action, as described in the Climate Plan.