~Comparing major sea ice melt years reveals a much mangled atmosphere and icescape
~The Arctic Atmosphere is very closely linked with sea ice morphology
~2019 outlook for sea ice has never been more grim
Arctic winters end in late April, so it is appropriate to look at winters imprint on the Global Northern Hemisphere:
NOAA daily composites, the real imprint of winter can be found right after peak cooling period, May 1-7 offers a glimpse:
1998 the then warmest year in history, really marked the start of visual from space Arctic Sea ice extent decline. Observe the massive North Pole centric CTNP (Cold Temperature North Pole), this was more usual when Arctic Ocean was covered by a much thicker sea ice canopy.
2007 The first really massive melt was just ahead, note the missing CTNP. And note as well the faint outline of two vortices one over each continent.
2012 the largest sea ice extent drop in history was to come, note the early ridging bands taking shape within a much shrunken Polar Vortex compared to 1998. These apparent waves or bands have a tendency to bring up warmer cyclones from the South or tend to create "Omega Blocks" with persistent stable anticyclones. Note the diminished size of the Polar Vortex as well.
2016 with the biggest El-Nino in history just past, a great year to compare with 1998. We can identify the wavier appearance of the Polar Vortex, along with "rogue" vortices , smaller but colder, quite a ways displaced from the North Pole as with 1998. The ice in 2016 was quite thinner than 1998, hence more heat from Arctic Ocean tendency to split the main coldest vortice in 2, usually moving them Southwards on each continents of the Northern Hemisphere.
2019 has the most disfigured Polar Vortex of all, almost with 3 distinct ridges having within smaller colder vortices again over the continents, The Jet Stream was equally wavy for most of winter just past. These ridges tend to accelerate cyclones Northwards or keep anticyclones very steady.
The most distinguishable feature between 1998 and 2019 is the disintegration or crumpling of the Polar Vortex coming along, not by coincidence, with the drastically diminished presence of sea ice in volume and extent. The term "Climate Change" is now literally readily observable not only in the atmosphere but on and in the oceans.
The end result of all this change can be observed by the rapid flow of much thinner broken up sea ice, which if we are fortunate, can flow within the Arctic Basin, but any massive favorable weather pattern may reproduce a bluer than ever Arctic Ocean, never seen before wide expanses of water, at any given melt season. It is not just a matter of time when there will be less than 1 million kilometer square of sea ice come September, it is a matter of luck that it did not happen, the greatest ally of ice as well are summer clouds, but if the temperature dew point spread widens from warming, thinning clouds and or especially vanishing ice enhanced fog will allow a far greater solar input. Chances for 2019 having the worse melt in history are extremely favorable because the winter imprint of cold was lacking and there is not much sea ice cohesion left, again it is best if there was a summer El-Nino, despite the counter intuitive warming El-Nino implies, without summer clouds the North Pole will be a sea faring waypoint. WD May 18, 2019
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