Average Arctic Ocean surface temperatures have a close relation to either sea ice or open water total areas.
These three measurable geophysical parameters are inseparable, they cause and effect each other to vary. The easiest one to immediately visualize is open water, dark, but warm especially in winter.
The period of greater demise for Arctic sea ice started in 1998, if we integrate the space under the DMI 80 N temperature red curve vs average in green, we may get a correlation with respect to open water extent. Note 2013 the last year with expansive sea ice after minima, the red closely hugged the green more often. Note the years 2016, 2012, 2007 and 2006 being particularly ocean blue with a largest integrated temperature areas matching open water extent or are very well reversely proportional with their lowest sea ice extents. 2004 temperature area integration is close to 0 which coincides with 2004 ice extent being pretty average. The pre 1998 curves appear to have a consistent integration much closer to 0 or less:
What we may conclude from these mental integrations: there's a hard road back to normalcy for sea ice to rebuild, if not an irreversible downward extent trend particularly demonstrated by a very large, the largest under temperature curve integrated area in 2016, indicating much more open sea water, it is exceptionally foreboding. WD December 13, 2016