~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.
The horizon elevations in all quadrants were consistently lower for most of the long night of 2017-18.
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