~First observed in spring 2017 by refraction sun disk method
~A surrounded shrunken by greater heat Polar Vortex gives deeply cold vortices.
December 31 2019, with Polar Vortex off center weighted temperature measuring -48 C CTNP over Ellesmere Island, the coldest such air ever measured for this date, surpassing all others by 4 degrees C (1948-2018).
In Purple, deeply frozen weighted atmosphere using 600 mb, the rough altitude giving the average temperature of the entire troposphere. Note the near proximity to much warmer air, by +23 C, within a mere few hundred kilometers, a feature of this phenomena. In the past, same date CTNP's were more Polar Vortex centric. This amazing phenomena coexists with a much warmer Northern Hemisphere atmosphere. With Jet Stream in some sectors way Northwards, at some locations brought Southwards by lower pressure found in huge cyclones. Without Low pressure systems, the outline of 600 mb at -25 C would be roughly the Northern end of the Jet Stream. This small but impressive -48 C CTNP vortice is about 20 C colder than normal for this time of the year, compared to all other years since NOAA daily composite allows, 1948, this region is the coldest New Years Eve in recorded history.
The best way to explain this is to balance the presence of much warmer air, being onto itself more stable, especially during anthropogenic enhanced global warming days, with a significantly smaller region of much colder air. A weather stable region in darkness or with very low sun, is bound to get very cold, because it is isolated, does not have a lot of heat input. This Ellesmere Island CTNP is a continuance of the same one which was further to the West 3 or 4 days ago, a cold vortice tends to place itself wherever ideal radiative cooling exists with very little heat advection or convection (from snow laced lands rather than thinner sea ice). WD January 3, 2020