Polar vortex spin off vortices, North Pole Cold Temperatures are Southwards well away from the Pole

~Polar vortex is the entire spinning of the Polar lower troposphere like a cyclone
~Vortices created within, sometimes one , two 3 or 4. Move about.

"A polar vortex is an upper level low-pressure area, that lies near the Earth's pole. There are two polar vortices in the Earth's atmosphere, which overlie the North, " Wikipedia

Not only 2,   there can be many vortices. This article from science alert is very good:

http://www.sciencealert.com/it-s-official-the-polar-vortex-is-back-with-a-vengeance

When there is an incursion of warmth towards the Arctic Ocean, like at the moment the vortices are pushed Southwards:



Northwards of Green delimited zone is the Polar Vortex of the entire Northern Hemisphere as expressed by NOAA 500 mb heights map December 15, 2016. Consisting of 3 vortices centers in dark purple, note to the right of each smaller vortex there is a Northward flow of air, to the left a Southward flow, yes it is cold in North America  however very opposite warm NW Europe. When a TV meteorological presenter says the "Polar Vortex" is back, he or she means a single smaller vortex part of of the entire Polar Vortex system. There is apparently no single word for 'vortice', hence the confusion of using Polar Vortex. Another way of presenting the case would be to say that the Polar Vortex is weaker, hence less circular, oblong and segmented by severe warming near or towards the North Pole. A single segmented vortex usually wraps the jet stream stream around it:



December 16 2016 CMC 250 mb chart. Blue trace my own. Within the blue trace is the center of vortices, there lies a surprise, it is the Cold Temperature North Poles. The coldest air possible.



CMC 500 mb chart December 16,2016. Although ideally the temperature of the entire troposphere is found by a 600 mb chart (they are rare,  can't find). We can clearly read -51 C close to Great Whale river Northern Quebec,  this is the center of the coldest air in the Northern Hemisphere,  note Ellesmere 1500 miles North, -30 C.    At center of CTNP the winds are weak to none, similar to center of hurricane but on a mega monster scale.

It may said that it is colder further South than the Arctic, these are the days when winter builds up over the continents, the Arctic Ocean atmosphere being much warmer affects the weather every where Southwards,  the term Polar Vortex should be explained more correctly because this implies a Colder very expansive Polar region,  in fact its warmer at the North Pole devoid of any sun light whatsoever.WD December 16,2016

Dramatic Arctic Warming captured with ice extent and temperatures: Area under the DMI 80 temperature curve biggest in 2016 in direct relation to substantial daily open water area.

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.

Sea ice extent variations by Cryosphere Today depict a steady
downward trend,  except of course for 2016 with numeric data calculation problems.
Obviously absent sea ice is replaced by open sea water.   The large 2007 and 2012 variations depicted above are largely due to favorable melt or compaction conditions as caused by Arctic Dipoles or rather large Cyclones mixing sea ice with already open water huge sea waves.  

    Visualize the graph year by year,  mentally calculate the area under the red curve with respect to green,  I calculate every year above 0 except for 2004.      

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:

      The integration of the space under the red DMI temperature curve with respect to the average should be close to or below  zero for every pre 1998 year,  considering when temperature is below average the calculated area is negative.

        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