Never so steady polar vortex circulation, strange things happen when nothing moves

 ~Take one day,  any day,  of the recent weeks,  and the weather image is close to the same.

~So much for chaotic weather

   First we observe winter 2021 Siberian Cold Temperature North Pole dominance,  a awe puzzling phenomena, which I have a somewhat good grasp,  but this is the main feature,  we start from there,  but was it always like this?

NO is the answer,  spot check 4 winter days in the not so distant past,  the year when Arctic sea ice was much thicker,  1977,  with Arctic sea ice wedged or ridged against the North American side of the North Pole helped create a colder region than Siberia.  Remember he Canadian Arctic Archipelago, prior to 1947 had very few people living there for a reason,  it was often colder than Siberia.   In this spot check, November 11, 25;  December 9 and 23 at 600 mb temperature, where the average temperature of the troposphere may be found without calculations.  3 out of 4 of these days,  the legendary bitter cold Siberia,  was warmer than the Canadian High Arctic. 

Fast forward 2015,  3 years after the famous 2012 Arctic Sea ice  minima melt,  there was the strongest El-Nino in history,   Siberia appears dominant cold 2 days out of 4,  yet ,  El-Nino was on the American side of the Pole, so this might be ENSO driven.  But recent years observations gradually place Siberia coldest atmosphere of the Northern world during the majority of winter days,  a shift,  largely due to the Northern Pacific and Atlantic being very warmed;

3 out of 4 same November and December days in 2021,  make Siberia the dominant Coldest Atmosphere ,  a huge pattern shift,  Ignore Greenland area,  the atmosphere at 600 mb is greatly influenced by ice, there should be dominance of cold air  at the top of a Glacier especially when 600 mb winds are calm, so a daily record must consider this.   Besides it rained at the top of Greenland this summer past:

 https://www.nbcnews.com/science/environment/rained-first-time-summit-greenlands-ice-sheet-rcna1723    

    Weather wise it has been weird, stranger than usual Global Warming induced changes,  the apparent stability of 2021 patterns have been uncanny,  gave results positive of nicer milder much warmer weather in Eastern North America,  and devastating floods in usually very weather quiet British Columbia.  Contrast the 1977 outline of 252 degrees Kelvin and the 2021,  same days,  weather systems flow around this limit,  which greatly explains why B.C. got a greater injection of extremely warmed North Pacific air.   

Prelude to the Late Great Arctic Ocean summer sea ice, the writing is in the air

 ~There is a minimal,  but valuable,  effort to measure Arctic sea ice in its 3d nature

~It is about to vanish in summer,  this is one way to  know it:

  October November Canadian Arctic Archipelago Upper air profiles have evolved.  They are more like Southern Canadian ones.  The main reason is the disappearance of sea ice,  mainly now in its thickness.  This allows heat from the even warmer ocean to transform the lower troposphere.  In effect cancelling the build up of winter to a lesser degree of magnitude.  The difference between tropopause temperature and tropospheric maxima has grown,  the tropopause is usually much higher,  the inversion heights from surface have dropped.  But in particular temperature profile maxima to surface lapse rate has shrunken significantly since 2019, indicating a massive warming, therefore thinning of sea ice,  no longer thick enough similar in nature to deep frozen land.   It would take a much larger intense study to confirm how wide scale this phenomena is,  it would take a huge recalculation of historical measurements particular data points from all stations, not readily available on internet, in order to pinpoint exactly when the Arctic summer sea ice will completely melt.  Assessing atmospheric measurements far more rich in data, would make it easier to predict,  the keen  Arctic Atmosphere mirroring current Arctic sea ice state, is a work around way to measure over all sea ice thickness,  but seems it wont be long before it will all gone.  When the High Arctic Upper Air becomes close to resemble the subArctic of the 80's (its warming there as well) , ie Hudson Bay for instance,  we will have a better idea.  WD November 21 2021

October 2021 total collapse of Canadian Arctic Archipelago cold air build up, never before observed

~Never recorded as such ,  incredible High Arctic warming goes irresponsibly unreported,  although its climate effects will surely be talked about.

 

IGNORE Greenland,  925 mb air temperature does not exist inside a massive 600 mb high Glacier.   Look at the blue 262 Kelvin  (-21 C) reading especially over the Canadian Arctic Archipelago,  October 2021 gone, despite 2016 ultra warm El-Nino and the much thinner sea ice since 2012,   This will surely make an impression over North American weather further South.  Not that it wont cool,  but the colder sting of dark winter will start very late, if noticed at all.  

Surface air temperatures are again non existent inside Greenland Glacier,  Look at the massive surface cooling effect of thicker sea ice in 1977.  Now thinner,  Arctic Ocean sea ice influence is in steep decline,  no longer builds a more round circumpolar vortex.  These irregular Arctic average temperature shapes are reflected everywhere further South,  thus the wild winter temperature fluctuations of late.WD November 14 2021

The Polar Vortex Fix; Near permanent Siberian dominance, especially over ENSO's influence

 ~Coming winter will likely be a warm one for North America

~Notwithstanding ENSO apparent LaNina?   

~As far as circulation is concerned the Polar Vortex rules the world

Take nearly any day in October just past and the vortex would look like above,  of which Northern Siberia was/is at the Cold Temperature North Pole (CTNP).  Northern Greenland and Ellesmere Island mostly strangely out of extreme cooling business.  Largely because of North Pacific incoming warm cyclones driven towards West Greenland by the same Polar Vortex,  a feedback loop.    If the extreme Southern location of the P.V. is way up in the High Arctic,  it goes without saying about the warmer weather further all the way South to Florida  

   Here is one Canadian Global News long range winter forecast ,  a fairly descent, standard, run of the mill projection about the coming winter, ENSO dominates the talk,  but the Polar Vortex does the walk...

     The NYTimes did a state of the comprehension, quite good piece on ENSO,  however it almost triggered the writer, Henry Fountain,  to look for circulation pattern causations elsewhere:

......"The changes in atmospheric circulation can result in changes in weather in various parts of the world, what meteorologists call teleconnections. Much of this is related to the position of the jet stream, the high altitude winds that sweep across the planet from west to east.

In El Niño, the jet stream tends to shift to the south. That can bring rainier, cooler conditions to much of the Southern United States, and warmer conditions to parts of the North. Elsewhere, El Niño can create warm, dry conditions in Asia, Australia and the Indian subcontinent. Parts of Africa and South America can be affected as well.

In La Niña, the jet stream shifts northward. That can lead to warm and dry conditions in the Southern United States, and cooler, wetter weather in parts of the North, especially the Pacific Northwest. Parts of Australia and Asia can be wetter than normal.

La Niña can also lead to more hurricanes in the North Atlantic because there is typically less wind shear, the changes in wind speed and direction that can disrupt the structure of cyclonic storms as they form.

It’s important to note that these are just typical effects. El Niño and La Niña sometimes don’t follow the expected patterns." (underline by me)

What is more to the point is that El-Nino and El-Nina don't appear to change circulation patterns pretty much already set by winter, or can you tell which of these jet stream average positions between January 1 and April 10 happened during El-Nino or La-Nina? :

   2 were El-Nino , 2016 and 19, two others under La-Nina 2000 and 08.

   Finally recall the forecast presentation ? There is too much certitude over the coming La-Nina, since 2016 ENSO temperatures tended to remain in the neutral temperature zone or at temperatures considered neutral, this was its main routine of late, briefly trending one way or the other never going too extreme. A week or so a La-Nina forecast was in the bag but now:

Not so blue cold.... wd Nov 7, 2021

2012 Great sea ice melt retrospective, it was predictable in April

~A refraction magic rabbit (a new way of seeing things,  to be published in peer review paper), popped out of the hat in early spring 2012.  

~It turns out a very warm spring atmosphere made it possible

~Comparison of top 10 sea ice extent melt follows:

Before we do top 10 sea ice melts,  let's look at 2012 vs 1977.  2011 sea ice situation was grim,  1976 was opposite, much more multiyear sea ice was covering the entire Arctic Ocean.  This made it easy for the Polar Vortex to be North Pole centric then.  Notice the green zone -30 C temperature area at 600 mb height (those favoring 500 mb can be greatly confused by stratospheric influences).    2012 was exceptionally warm for the Canadian High Arctic (so did say the rabbit).  

                        Likely #11,  2021

What happened in 2021?     After all 2020 was 2nd place in sea ice extent.  The vortex regained the Pole,

this guarantied a great influx of clouds from the North Pacific sea surface temperature '"hot" blob,  in addition to accelerating importation of moisture by equally super warm North Atlantic, summer Arctic clouds save ice from melting completely hence the appearance of a cold air recovery.

8th Place, 2008 the LaNina Spring super sunshine melt ponds

   2008 vs 2012  LaNina was raging in 08 giving a reduction of clouds ,  causing more insulation, but starting from a much colder spring atmosphere. 

   In 7th position:

Spring 2011 was almost bipolar for the Polar vortex, the Canadian Archipelago very strong vortice of the Polar Vortex assured 2 things,  dry air from North Greenland towards the Pole and the wet North Pacific moisture trust directly towards the North Atlantic,  in imagery words,  apt for good solar input for the Arctic Ocean,  

#6  2015 the warmest year in history then

The waning -30 C green zone plus the Baffin Bay centric center of the Polar Vortex,  similar to 2011,  assured 2015 prominence in melting.

#5   The sun melt year: 2007

2007 600 mb  spring temperature was practically similar to 2012 the area having the greatest melting by sunshine was North of Alaska Beaufort sea  we can see clearly a favorable North Siberian in provenance circulation of dry air. 

  #4  super ENSO warming; 2016 

2016  green -30 zone shrank to near 2012 dimensions along with a stifling encroachment of red (-24 C) areas all throughout the Arctic ,  again favoring dry air from Siberia sun warming.

 

3rd sea ice melt place; The great small but very cold CAA Vortex 

2019 may seem much colder than 2012,  however North Atlantic and Pacific had a very warm spring atmosphere.  Again key,  dragging dry Siberian air over Alaska and Eastwards,   The Canadian Arctic Archipelago vortice was measured stubbornly in place for the longest time assuring these dry (less cloudy ) air conditions. 

2nd only to 2012:  2020

The second most powerful sea ice extent melt had no blue zone (-33 C) similar to 2016,  we can also note the heat strangling cold areas red zone, particularly South Greenland Baffin Bay,  but in particular the position of the polar vortex center,  North Pole centric,  not because there was thicker sea ice there , but because it was coldest there.    A stable warm area encourages a stable cold center which was the Pole. Also noteworthy; North Alaska air being warm after the long dark season seems to assure a forthcoming great melt

    All in all we can now project with a greater deal of precision whether the sea ice minima will be small by mid-April,  another prediction tool thanks to said "rabbit" refraction trick which suggested looking at these holistic temperatures.  WD October 30 2021

Cloudy days heat transfers, 3d sea ice transforms, a different perspective about 2021 summer sea ice melt

   October 6 2021 arrival of Arctic Ocean multi-year pack   completely flattened,  thin,   not changing sea water temperature a great deal,  not stimulating new ice to form.  Of which sea water temperatures were abnormally warm,  despite said presence of pack ice. Open water above 0 C temperatures of end of September rivaled 2012 same date measurements.  

~It is important to consider sea ice extent in all its dimensions.  Not just compare the horizontal one.

~Whereas a penetrating 2007 or 2012 sunlight melt didn't occur,  there was a great loss of ice nevertheless

~The proof is in the size of multi year pack ice,  usually seen floating away from the Arctic Basin looking like a mix of first year and much older ice with various height profiles,  giving the impression of a spectacular jungle of sea ice vertical shapes, 2021 had no such great old tall forms to observe.  

  Surface temperatures October 2021 are the warmest the Canadian archipelago had in history,  despite 11th place finish of Arctic sea ice extent at minima.  The disconnect between the two suggests a much warmer sea,  spreading around heat more evenly,  even under a huge area of intense cloud cover lasting months, with very little insolation to speak of. 

2021 October 26 (left) and 25 frost and drizzle accretion,  South Cornwallis Island (-1 C weather).    With end of October 16 C above normal,  almost everyday was at record or is a record maximum temperature for the entire month!

      October 6 sea ice arrival,  speaks for self,  especially for those who are use to seeing fall ice movements. WD October 26, 2021

2021 sea ice minima story, it was bad, despite what the numbers suggest.

 ~Hi,  nice to be back after a little break

~ I did not expect 2021 Arctic sea ice minima to be greatly shattering 2012 record because of North Pacific in origin clouds.

~Summer 2021 clouds were even more extensive than expected since even the Atlantic sea surface temperatures were extremely warm as well.

~ With these overheating North seas,  there was no way for an expansive prolonged  sea ice exposure to summer sunshine. 

~Yet this was a terrible year for sea ice nevertheless,  despite 11th place historical finish,  the remainder ice seen streaming through Arctic Archipelago Straits were never observed so thinned, demolished, emaciated and flattened.  

2021 sea ice minima was a good 1.4 million square kilometers shy of 2012,  failing 2020 2nd place as well.   But there is a difference between these years,  and it was cloud pervasiveness,  which persisted and continues till this day going back to June.  There is also quite compelling piece of evidence of sea ice extent being near all time lowest at present, in summary:  no recovery at all is at play,  rather a form of heat embedding through different means.  Clouds during Arctic summer make it cooler,  but come fall if continued,  flip autumn temperatures much warmer:

NOAA 30 day surface temperature anomaly says it all,  the Canadian Archipelago average temperatures are hovering between 10 to 20 C above normal.  This does not stem from much more minima sea ice,  but from a warmer Arctic Ocean which has not melted completely because of extensive cloud cover, end of summer clouds saved the ice but did not foster rather stymied a cooling rebound.  

   Extra wide areas of extreme warm sst's for both North Atlantic and Pacific are the prime source of world wide heat injections particularly by water vapor,  a potent greenhouse gas,  which adds to the others us humans tend to dump in the air.  

   Next reports will cover the emaciated looks of surviving multi year ice,  why Siberia is now the last refuge of winter buildup and a retrospective of 2012 minima, which was baked in the spring well before summer solstice sun.  wd October 21 2021

AFTER Switchover sea ice doomed by warm Highs

 ~Reminiscent of 2007,  any anticyclone lingering over the Arctic Ocean means rapid melting

~Remarkable weighted temperature differences between Low and High pressures are already in place

CMC June 6 2021 700 mb,  close enough to 600 mb ,  temperatures within all Arctic Lows are significantly colder than at centre of anticyclones, of which a remnant of the once persistent High over the basin Gyre is hanging on.  But the switchover id definitely done,  disrupting the transpolar ice stream,  

NASA EOSDIS May 31 June 6 2021,  one should not underestimate this smaller High pressure,  either

for melting or moving sea ice.  If the High remained over the Arctic Gyre,  it would have been even more devastating,  circa 2007.     Notwithstanding clouds,  an enormous amount of open water occurred in the Beaufort sea area in a few days,  very early in the melt season,  thinner sea ice,  likely present at extent maxima, has no chance to  last long against the sun.  Note the rapid melting of snow Northern Yukon and NWT with mainly lake ice remaining. WD June 7 2021 

Spring 2021 switchover , transpolar drift staller

 ~Most likely occurring today.

~But not after a great sustained Arctic Basin Gyre did its thing.

 A typically strong Arctic transpolar stream  is pushing out sea ice in great volumes,  but the results are not quite showing since North Atlantic melting has begun.  ITP map

May 30 polar View  SAR shows the exit of old sea (right) pushed by thinner sea ice (top left) which will settle most likely North of Greenland soon,  and there will be great open water  there.  

   It will settle because: 

     CMC prog,  18 UTC may 29, followed by 00-06-12-18 UTC May 31.  Look in particular for the High over Northern Quebec and Atlantic, plus the Low pressure system NW of the Canadian Arctic Archipelago,   this Low already stubbornly present, will persist to affect the sea ice current in favor of saving the sea ice from landing in warm Atlantic waters.  But all the ice dumped to Fram Strait , East of Greenland will melt,  its sort of deja vu dynamics going back a few recent years.  The 2nd smallest minima in history, last September,  gave a lot of new sea ice, melting in place thinner sea ice depends on clear skies, which will happen pretty much everywhere outside of a hovering Low pressure system.

But if 24 hour sunny,  with cleanest air in decades,  which explains the current melting tardiness, melting will be very swift.  WD May 30, 2021

Summer Threshold switchover, when High's become warm and Low's are sustained by cooler air

 ~It is just about to happen,   after long sojourning Arctic Basin High pressure system  

~Impacts sea ice survival in a big way

    The reasons why cyclones persist more in cooler summer weather are obvious,  they cast a shade from the sun.  In the Arctic it is a bit more complex,  sea ice helps create clouds as well,  more of it causes a cloudier Polar summer. Moist air hitting an ice pack easily fogs up,  fog is a cloud touching the surface.   Onto itself summer sea ice and cyclones are a pair,  so it is not surprising that summer Lows tend to survive longer above ice. But there is a time,  such as now,  when cold Highs and Lows may subsist simultaneously:

  3 CMC surface progs, 23 May 00 UTC,  23/06 and 23/12 UTC +extra 700 mb 23/12 UTC.  All showing a less imposing Arctic Gyre High,  apparently moving towards the Canadian Arctic Archipelago where it will eventually be just South of it,  and a 1008 mb Low over the Arctic Ocean Gyre.   Where it will stymie the sea ice exodus towards Fram Strait,  just Northeast of Greenland.   The 700 mb chart portrays this High and Low as having about the same temperature,  this anticyclone will warm a lot,  because it is allows sunrays through,  opposite to the Low, basking in cold, sustained by sea ice,  cloudy weather.  The split in behaviors is temporal in nature and will revert back opposite coming September.  Clouds are essentially all there is stopping a massive catastrophic sea ice melt.  But this is a "frustrated" but nevertheless end of La-Nina weather cycle,  meaning over all lesser clouds and especially warmer High's significantly warmer by lesser pollution at end of Covid pandemic.   WD May 23, 2021

A much warmed and disorganized Polar Vortex created a steady deeper cooling at its center.

~Stable warming of the Polar Vortex is seldom uniform in shape or temperatures.  

~This warming can cause a sudden cooling zone anywhere with very long exposures to the frozen ground and of course by prolonged cloudless air

~Recently we have had a very neat example.  

           Early may 2012 Arctic weather was incredibly warm,  this warming has not stopped,  it kept shrinking  a mangled Arctic Polar Vortex,  but suddenly 1 week later ,  under an even warmer rising sun,  what appears to be impossible occurred:

A small deep cooling area appears near the Pole May 10 (still with a low sun),  it moved over the Canadian Arctic Archipelago where the air was clear,  notice its temperature colder than about 2 weeks prior  (May14) ,  although much smaller, it is strikingly keeping cool despite the P.V. even more dismembered and severely encroached by warmer air all around its perimeter.    What happened is a classic Geophysical phenomena, under certain conditions atmospheric temperatures may drop if  the weather is right,  despite the rapidly approaching summer, despite over all abnormal warming.

This feature can be observed at any time of the P.V. existence.  For instance,  the Northern US can

be coldest place of winter to date more than anywhere else in the Northern Hemisphere.  Notice I use use 600 mb temperature because it is the closest pressure level representing the temperature of the entire troposphere.  500 millibars is more representative of the entire atmosphere, on occasions the stratosphere can be unusually warm or cold,  and can distort tropospheric tendencies if judged by 500 mb maps. WD May 16, 2021 

Arctic 2021 almost just as warm as spring 2016??

 ~However spring 2016 was part of the warmest El-Nino in history

~While spring 2021 is part of the coldest La-Nina since

There is something out of the ordinary coming about:

NOAA ENSO Table,  look carefully at 2015-16  ,  it was really the winter of 15-16 which was very warm,  likewise EH2r vertical sun disks of Spring 2016 were amazingly expanded, in fact all time record number expanded.  Followed,  not surprisingly by 2015,  2010,  all El-nino winters. Climate wise,  the Arctic temperatures zoomed up in 2016,  the gold standard warmest since 1998.   

As a useful weighted temperature of the entire Troposphere comparison,  2016  May 3 date ,  can be compared with others,  averaging out a week or or month would blur the image so much,  it would be difficult to judge the extent of warming.  Any ways,  2012 was end of a very long La-Nina starting in summer 2010. Hence we see a marked ENSO footprint.  The Polar Vortex was of a different nature in 2012,  consolidated, less broken,  as if something more frozen just happened....  Of course 2012 is the year when Arctic sea ice minima was lowest to this date.  

2016 vs 19,  both springs had a winter El-Nino,,  both had broken May 3 P.V..

Of which its internal vortices unleashed their own regional climates.  

A neutral look,  Sprig 2020 came after a neutral ENSO period,  the Polar Vortex was more reformed,  much colder than 2016.  But all is not well, the broken up aspect of the P.V..  perimeter persists.  Since after 2016,  spring time vertical sun disk diameters reflected the consolidated coldest vortice hanging about the Canadian Arctic Archipelago.   

Very strange,  2021 May 3,  quite similar to 2016,  in warmed temperatures and configuration.  Yet

as the ENSO table demonstrates,  the ENSO's are polar opposites,  16 followed the back end of El-Nino and 21 back end La-Nina.  A significant  Canadian Archipelago vortice is still important in 21,  but not as strong as previous years since 2016.  While comparing with 2012,   with very similar ENSO,  2021 is warmer than 12,  refigured like 16,  as if current La-Nina had no effect on the Arctic system.  The only reason this can happen, warmer Oceans ultimately affecting sea ice,   if thinner,  the heat emanating from a huge area would erase the Nina effects.  The warmer Northern Oceans had something to do with tis as well.  WD May 9, 2021

EH2r annual spring summer projections, in greater details, massive heat wave foreseen

~Simply extraordinary systematic Arctic surface air warming, caused newly discovered optical phenomena

~Vertical sun disks in the middle of the pack,  analyzing a much weakened out of normal position Cold Temperature North Pole

~Extra clear air,  confirming a depolluted Arctic atmosphere and a quiescent La-Nina  unable to compensate for historically warmest 2016 El-Nino 

    Since 2016,  the year with the warmest El-Nino in history,  everything was changed further, culminating to Nothing:

     No streaks,  pure molecular air,  a sure sign of de-pollution and especially La-Nina,  no evidence of cloud seeding high clouds,  nothing again and again:

  5 days later April 20 2021,  a totally clear high altitude sky,  sure sign there was or  is a raging La-Nina,  but look at the ground,  with a near record snow cover.  It was cloudy of course, much cloudier than a usual La-Nina spring,  but this snow comes from another sea surface, almost inclusively from  the North Pacific:

Impressive North Pacific high temperature blob anomaly,  currently survives the strongest La-Nina since 2016.  The main difference between a North Pacific warm SST and El-Nino  are the clouds, the Tropical Cumulonimbus are incomparable in height and duration,  they fuel the lower stratosphere with cloud seeds,  which go all over the world.  However, a North Pacific cyclone system has considerable moisture,  which during especially during Arctic fall-winter-spring,  turns to snow.   

   Given that I estimate a very much diminished Polar Vortex (P.V.),  despite La-Nina,  the course of things can be a bit strange.  North Americas main moisture source will come from the Northwest for the earlier part of summer.  Leaving the greater portion of the continent only changeable by synoptic weather,  no longer in the grip of the P.V. sphere of influence.  

Vertical Sun disks; what is the score?

     The vertical sun diameter is a giant thermometer,  taken at the right elevation ,  it purely reveals the temperature of the entire atmosphere.  Since 2016,  another shocking turn occurred,  the disks shrank

despite much warmed world temperatures.  That is because the center of the Polar Vortex,  at its heart, is the Cold Temperature North Pole (CTNP).  since 2016,  the spring CTNP remained steadier over  the Arctic archipelago,  as opposed to the past when it was further South.  The pre 2016 CTNP was found mainly to the South of the Canadian Archipelago,  with a slow move Northwards,  culminating at Northern Ellesmere Island by mid spring,  vertical sun disk dimensions traditionally reflected this movement.  With disks usually bigger in late winter,  then shrinking as the sun rose,  because I was eventually measuring the CTNP from within.  It was not unusual for late spring measurements to have the smallest vertical sun disks.  All this changed after 2016, when  I strangely measured smaller disk diameters for a greater portion of time,  almost all the way to spring end. This made the average vertical sun disk measurements at all time lows since 2001.  In effect skewing its predictive powers,  which made it easy to predict the year end Global Temperature results.  

     Now I keep in mind the location of the CTNP,  which this season was mainly to the North, or at various apparently random locations,  a sure sign that the Vortex has left or has become severely weakened and or shrunken.  With this in mind here are the results:

                                                              ranking,    year,    #1 average maximas* 

*Of 12 decimal levels,  from -1 degrees  to 10 degrees astronomical elevation

      2021 has jumped above the last few years bottom trending to mid pack,  10th place, with 6 average decimal elevations being at all time maximum.  From more than 420 measurements,  taken not often from the CTNP center.   Sun disk  ENSO projection  has been completely muddled by the North Pacific blob sst,  although there is still a correlation,   the measurements of this seasons sun disk coincide with the last phases of a modest La-Nina lasting 7 months,  as long and and in a similar period to 2017-18,  the difference being the observation position mostly away from the Polar Vortex center.  A greater number of sun disk diameter expansions was expected because of very warm surface temperatures,  but the Upper Air still was more normally cold. 

Global Temperatures

        Past measurements of sun diameters were sufficient to predict the annual average temperature of the Northern Hemisphere, but the continuous climatic repositioning to the CTNP makes it more difficult to do so.  But the frequent repositions onto itself is a predictor.  As posited on previous general description article,  the P.V. has been consistently way North its usual locations.  There is no way to have winter reformed in the middle of May.  Therefore this high latitude CTNP in late spring means only one thing,  extremely warm temperatures for most of North America,  with rain for Alaskan coast (seasonal temperatures).  

   Arctic Sea Ice 

               There was another astounding event coinciding with the warmer surface  temperatures,  April 2021 will be on top of the list for the warmest April in Canadian Arctic  history.  At present, Arctic sea ice thickness is locally very thin (middle of Canadian Arctic archipelago), likely all time thinnest.  Therefore,  it is easy to surmise, an early collapse and total melt devastation of sea ice,  but not so fast,  North Pacific moisture will bring more rain to the Arctic and of course greater cloudiness.  The question is whether rain can do in sea ice as fast as the very hot sun?  Is a good one,  we shall see.  But I think the NE passage will still open before the NW by a few days.    Over the Arctic basin,  its again a question of clouds,  this time with less rain,  so I predict (as a measure to see if I understand the geophysics) 2021 sea ice minima slightly smaller than 2012.

     Another fact to keep in mind is top of sea ice (implies snow layer as well) ,  never warmed to same temperature as surface air until April 30 (the latest since observations began in 2010).  This can be optically seen,  if the surface air is always warmer than top of sea ice,  the "first melt"  observation can never be made.  First melt is optically   determined when the top of sea ice temperature is the same as the air immediately adjoining.    Every other year had thicker  or much thicker sea ice.  This late f.m. date is understandable considering the current greater snow insulation cover.  It stops the further warming of more exposed top of sea ice.    Thus extreme snow cover will again tend to complicate prediction models. 

March 21 2012 First melt (left),  while a bit later sea ice horizon rises.  The earlier the first melt the worse the coming melting season,  it was once thought,  but now extreme snow cover implies the very opposite but with the same devastating summer melt.  

  With thicker sea ice , and colder (note the April 11  -31.2 C)  clear weather,  it was possible to reach "first melt" elevation level on April 15 (right ) .  When this occurs there is a thermal balance between top of sea ice and the air right above,  the sea ice horizon becomes the astronomical horizon.  

     In summary ,  end of spring and summer 2021 will be hot,  because the Polar Vortex lost its cold air grandeur. The Global circulation will tend to be stagnant,  favoring weather moved by a much lesser temperature differential,  with no significant Polar driven circulation movement until October.  WD May 2, 2021

    

EH2r Annual Spring Summer projection by mainly unorthodox means, brief General Circulation

 ~Hot spring summer for North America,  #1 warmest year in history.

~  Is strange, since La-Nina usually cools the planet

   Lets take a summary look:

 April May, the unusual position of the North American Polar Vortex extreme limit existed nearly all winter so,  this projection not a difficult call,  except we are dealing with unknowns,  such as different patterns from the onset onwards.  Early on, over the Arctic Ocean the usual North of Beaufort sea High will remain strong by not so apparent but somehow present La-Nina,  exacerbating Fram Strait sea ice flushing.  North Atlantic and Pacific usual Lows will impact B.C. Canada and UK along with NW Europe, mainly carried over by the Jet Stream (edge of P.V.).   Obviously the extreme North positioning of the jet stream slows the circulation to its South,  from present gently, to a crawl in the fall, and brings out the best or worst of weather.  This shift makes tornadoes more difficult to form in the deep South.

However this repositioning always dries up California,  not so good.  I would expect a wet UK, not so unusual.  The big story is the not so much measured La-Nina, whose effects are in some regions almost completely smothered by the North Pacific warm surface temperature blob.  So I'd expect less wet than usual a soggy Ireland Norway and UK a weaker flow from the Southeast would do so. 

June July,  Beaufort Gyre switchover from a stagnant High to a near permanent cyclone will occur very early in June if not earlier.  The reasons for this are La-Nina and greater over all Arctic warming. The dumping of sea ice East of Greenland would be less severe, and the cloud cover provided by an Arctic  Low pressure system usually overestimates sea ice melting predictions.   The shrinking Polar Vortex will ultimately provide for higher pressure systems to linger on top of the Norther Hemisphere continents,  as well as high latitude sea born cyclones, the difference being,  with a strong sun the June July High pressures usually provide greater warming,  and a drying feedback contributing to further heat, hence anticyclonic dominating the fleeting less vapor rich weaker cyclones.   Thus Northern Hemisphere lands  will be High pressure prone, leaving the Arctic a haven for cyclones,  a place for clouds to be strong in numbers. NW Europe will witness nice clear truer color sunsets more often than usual.   Siberia will be in a likewise summer 2020 heatwave as well,  the main reason being threefold, one is the invisible La-Nina (less clouds),  the weaker flow of warm Atlantic moisture, and the much cleaner air given by the last days of Covid-19 atmospheric de-pollution. 

August-September much like 2020, except the CTNP will be close to vanish ,  not to be found even where the remaining sea ice will survive the summer heat onslaught.  But at September end, I expect the first winter High near the North Pole Greenland area. The time for switchover back to winter mode over Beaufort Gyre,  will be crucial in saving what is left of the sea ice as well, I think the steady Gyre High will come very late though,  not enough to have a greater melt season impact.  This period is usually very interesting,  because summer rages further South while winter starts at the Pole.  The Low and High pressures switching from favoring warm or cold modes get blurred at the climate starting to expand borders. Likewise, hurricanes,  end of summer creations, clashed with the beginning of the Polar Vortex for milleniums.  These geophysical encounters moved the hurricanes rather rapidly. As a result of dramatic Polar warming they will move less but can cause much more damage,  even if landings to ground become less numerous,  because  lesser longitude wise life  is a direct result of a warmer autumn Arctic.  At about the onset of the North Pole long night,  Greenland, because of its nature of being colder than surroundings, may prompt a  steadier High Pressure above the warmed North Atlantic, encouraging hurricanes to hug the America's coast on a slow journey Northeastwards.  In contrast, of the North Pacific where a lower sun effect will meet the quasi constant Pacific warm temperature blob,  a year round source of strong Arctic 'hurricanes' , the violent cyclones,  which in the past has exposed further the grim state of summer Arctic sea ice. 

     The only thing really unknown is the new state of circulation affairs,  what will a non existent really normally perennially cold Polar Vortex world look like?  We are about to find out.   WD April 25, 2021

Incredibly steady 0 C sst shift, even if it is about our Great Lakes

~Winter 2020-21 was unbelievably warm for North America

~None better example than the 0 C temperature Isotherm

   CMC daily sea surface temperature chart shows also theoretically calculated 0 C line over land,  it has been well North of the Great Lakes for months.  In the recent past winters,  this line was usually at the Great Lakes Latitude.  This is yet another example of staggering warming due to a major circulation change,  which maintained the center of Cold Temperature North Pole (CTNP) ,  on the Siberian side of the circumpolar world.  Ellesmere frequently was the CTNP center of late,  but only for a few day cycles,  always bashed back warmer repeatedly by North Pacific in origin moist cyclones.  As a result a good chunk of North America has has had a warm start of Spring:

        NOAA 30 day surface temperature anomaly,  the blue Siberia Alaska bit portrays the Central Eurasian dominance, tagged along with short time cold air buildup cycles formed in the North Ellesmere area, not captured on a monthly average,  almost continuously sent to the Southwest, giving the brunt of High Arctic cold waves to the Western NWT.  WD April 18, 2021......   Yearly projection is coming next,  as you may guess,  there is absolutely a warm Spring-Summer already set.  

Dramatic Climate optical changes, significant effects from thinner sea ice

 ~In a short time span Arctic spring and autumn days have shortened.

~A very good reason why Northern Hemisphere circulation is changing aside from warming temperatures:  thinner sea ice.

~ This can be visually observed multiple ways,  all to to with atmospheric refraction.

     The latest Arctic warming can be summed up in 3 periods by sunset tardiness, of which some part of the sun disk can be seen well below the astronomical horizon (A.O. :  horizon seen if there was no atmosphere). In the High Arctic Cornwallis Island some sun disks parts have been seen lower than -3 degrees (that is 3 degrees of arc below astronomical horizon).  Furthermore when seen so much below the A.O.  under the violet sky,  sunsets shift Northwards quite a lot,  prolonging the day. 3 recent periods of concern would certainly be 2001-2005 ,  the last thicker ice years,  2005-2010  intermediate warming/thinning of sea ice, 2011 to 2021 severe thinning years,  of which the first period had 6 Month of March sunsets 2 degrees below astronomical horizon,  the intermediate period had 3,  the longest lasting period of 11 March months had  only 3,  this is a serious decline in optical properties caused by sea ice and air interface.   Visually this can be studied in greater details,  although I have no illusions about how convincing these images can be,  atmospheric refraction is very poorly understood,  I'll endeavor to explain nevertheless:

March 20, 2021.  At first the sun appears red and reddish throughout,  by moisture,  March 2021 had more snow,  more encroaching Pacific cyclones, than perhaps in the entire observation period of 2001 to 2020.  This sequence has been captured in a brief cooling  build up period between cyclonic storms.  The sea ice at horizon is also at thinnest recorded levels.  The sunset was not tardy, -1.39 degrees below A.O.  .  The main feature of interest is the lack of laminas,  the lack of roundness.  At end you see the beginning of purple sky light.   Basically there was no great temperature gains near the surface upwards.  This makes for a rather ordinary (for the Arctic) sunset.

 March 19,  2009,  much drier air,  therefore much cooler over all winter,  on this moment -35 C surface. 

These impressive presence of laminas are a feature of a colder atmospheric processing,  these occur when there is layers of warmer air above, but with very cold interface between sea ice and air in light or no winds.  These laminas rose undisturbed by strong winds, forming multiple thermal layers in stable air,  again a feature of a long time cooled surface facing the rising heat and sun as winter ends and spring begins. 

   March 19,2010.  a windier sunset, but with great thermal rate difference,  it was -33 C a few hours back, at this sequence it was -23 C causing a lapse rate favoring an extreme late sunset,  indeed 1.93 degrees below the horizon.  Warm air advection is one cause of sunset tardiness by reasons of refraction optics.  The cold ice did not warm up instantly, as the air just above changed,  for this to happen in greater winds,  the sea ice must be thick and sluggish in warming.  

      One may not conclude a great Climate Change with one observation moment,  rather it be known,  the entire EH2r corpus of data,  likely 10,000 individual sunset sun disk observations, which have gradually evolved into mundane sunsets rather than exciting colorful, extremely strange, lines upon lines stretching to "fire on the ice" sun line before dusk.   What we are witnessing is the signs of drastic warming affecting all visual aspects of land, sea and even winter. WD April 6 2021