~A recent steady continuous influx of Cyclonic moist air originating from the North Atlantic steered counterclockwise around Northern Greenland often did not show up as clouds
~Upper Air remnants of moist air mixed with smaller deep cold CAA vortice usually hanging about 67 North 85 West for weeks.
~This vortice was like a "black hole" steering all atmospheric matter around it.
~Many were observed as having clear air exotic moisture events , which despite apparently no clouds, transformed the horizon as if there were clouds.
~This meant Long Wave Radiation did not freely escape towards space and gave very low sea ice horizons.
South Cornwallis Island, it was -34 C on January 21 2018, with apparent clear skies, further to the South it was much colder. This very low sea ice horizon is counterintuitive, does not respect the concept of clear air Long Wave radiation escaping to space. Unless the upper Air profile has Long Wave reflecting moisture rich layers. Precipitable water was a mere 2.7 mm. At this horizon altitude, there is much less sea ice accretion than when top of sea ice/snow is super cold, when top is extremely cold the horizon can rise up to 3 times higher, in fact measured sea ice thickness stalled for weeks along with sighting such low horizons.
The horizon elevations in all quadrants were consistently lower for most of the long night of 2017-18.
Jan 22 00 UTC 2018 71924 Upper Air relative Humidity profile vs Altitude, it wasn't a dry profile despite 2.7 mm total precipitable. Some of the moisture layers had exotic Long Wave properties
which reflected back Long wave radiation as if there were clouds.
University of Wyoming map Jan 22 2018 00 UTC, total precipitable looking throughout the Arctic , there was not much water in the atmosphere basically everywhere, but water can take many forms, either from super cooled to many different species of ice crystals. In the Canadian Arctic Archipelago, some had "cloud like" properties, despite not being seen. WD February 27,2018