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Aikimox

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Re: The 2016/2017 freezing season
« Reply #450 on: October 31, 2016, 04:40:22 PM »
Meanwhile we are over 500k km2 below 2012 for Arctic and now matching 1986 for lowest extent in Antarctica... 

jdallen

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Re: The 2016/2017 freezing season
« Reply #451 on: October 31, 2016, 04:50:52 PM »
The Beaufort, Chukchi and Barents seas are seasonally ice-free now, with all that that implies....

Shouldn't it be Kara Sea instead of Barents Sea? Most of the Barents Sea is year-round ice-free.
The Barents has gotten quite a bit of ice as recently as 2014.  A totally ice-free Barents Sea at this point in the year is a very new phenomenon - new not just to this century, but to this *decade*.
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Tigertown

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Re: The 2016/2017 freezing season
« Reply #452 on: October 31, 2016, 05:49:01 PM »
NSIDC has stalled a couple times in the last week and finally did a back-slide.

2016,    10,  25,      6.956,     
2016,    10,  26,      6.965,     
2016,    10,  27,      7.006,     
2016,    10,  28,      7.103,     
2016,    10,  29,      7.111,     
2016,    10,  30,      7.048,
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Tealight

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Re: The 2016/2017 freezing season
« Reply #453 on: October 31, 2016, 06:40:18 PM »
The Barents has gotten quite a bit of ice as recently as 2014.  A totally ice-free Barents Sea at this point in the year is a very new phenomenon - new not just to this century, but to this *decade*.

To be exact the Barents Sea is between totally ice-free and seasonally ice-free. If I combine the highest extent of the last 10 years, over 50% of the Barents remained ice-free.

My comment was meant to question the group: "The Beaufort, Chukchi and Barents seas "
The Barents sea just doesn't fit in because unlike the other two it doesn't completly freeze over in Winter. The Kara Sea would fit this group much better.

Sigmetnow

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Re: The 2016/2017 freezing season
« Reply #454 on: October 31, 2016, 09:43:25 PM »
Eric Holthaus:  Parts of the Arctic are currently more than 20 deg C warmer than “normal”...
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jdallen

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Re: The 2016/2017 freezing season
« Reply #455 on: October 31, 2016, 10:00:47 PM »
<snip>
<snip>
My comment was meant to question the group: "The Beaufort, Chukchi and Barents seas "
The Barents sea just doesn't fit in because unlike the other two it doesn't completly freeze over in Winter. The Kara Sea would fit this group much better.
Point taken. 

I'll still hair split with you a bit over it, in so far as the Barent's extent at this stage is significantly down from where we would normally expect it to be, considering the historic behavior.
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jdallen

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Re: The 2016/2017 freezing season
« Reply #456 on: October 31, 2016, 10:03:25 PM »
Eric Holthaus:  Parts of the Arctic are currently more than 20 deg C warmer than “normal”...
Key take-away from that image is *ALL* of the Arctic Ocean is well above normal.  That means areas already frozen are building that much less ice, even now.
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jai mitchell

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Re: The 2016/2017 freezing season
« Reply #457 on: October 31, 2016, 10:33:19 PM »
we are observing a post ENSO driven shift in the climate regime of the Arctic. 

This is not albedo-driven warming as the regional heat and temperatures were not expressed until refreeze.  Note that this trend of temperature abnormality in the low-insolation months was expected with increased water vapor intrusion from the mid-latitudes and the collapse of the polar atmospheric cell.

note continual northern latitude blocking pattern driven intrusion of mid-latitude moisture into Arctic region

http://weather.utah.edu/index.php?runcode=2016103112&t=gfs004&r=NH&d=DT

See the animation of tracked warmth/water vapor here:  https://earth.nullschool.net/#2016/10/31/2100Z/wind/isobaric/700hPa/orthographic=-154.71,78.97,816

this is our current graph of SIE, note that this metric is no longer a good comparison with previous years due to loss of multi-year ice

attached below:

If >80'N avg temperatures and SIE comparisons are any indication we will be approaching the 2012 absolute minimum sea ice volume in PIOMASS for both the Nov 1st and October monthly average values (should be slightly higher than 2012 in both measures)

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oren

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Re: The 2016/2017 freezing season
« Reply #458 on: October 31, 2016, 10:52:42 PM »
This is not albedo-driven warming as the regional heat and temperatures were not expressed until refreeze.
Not disagreeing with your post, just nitpicking with the quoted comment. I believe that the early melt out of peripheral seas like the Beaufort did help accumulate heat that made itself present at the end of the season. In addition, I have a nagging gut feeling that the long time from melt to refreeze in those areas means that surface salinity managed to go higher over the season and the surface water became well mixed, and this in turn helps postpone the refreeze. This can possibly be verified by someone with more knowledge.

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Re: The 2016/2017 freezing season
« Reply #459 on: October 31, 2016, 11:03:54 PM »
Shouldn't it be Kara Sea instead of Barents Sea? Most of the Barents Sea is year-round ice-free.
Barents has been ice-free in summer since about 1990 (with outliers on both sides). And never ice-free in winter (though we are slowly getting there with a record of <0.5 Mio sqkm in 2011/12).
Kara is more recent - summer ice has been lost around 2005, and 2011/12 and 2015/16  have been the first incidents ever of incomplete winter coverage. I suppose you forgot how _fast_ things are changing up there. A-Team probably has a longer baseline of observing them than you.

jai mitchell

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Re: The 2016/2017 freezing season
« Reply #460 on: October 31, 2016, 11:08:51 PM »
If the albedo driven warming input was that significant then we would not have such a high average october temperature shift (as compared to 2007 and 2012), plus the regional temps were already breaking records BEFORE the melt season.  Not saying that there is NO imput from albedo (there is) but that the impact of a collapse of the Polar cell is now observable.  I attribute this directly to the increase in water vapor levels and upper tropospheric warming (and resulting increase in 500mb heights) as a result of reductions in Anthropogenic SO2 emissions.

note Svalbard (black is normal temp)

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jai mitchell

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Re: The 2016/2017 freezing season
« Reply #461 on: October 31, 2016, 11:15:20 PM »
Parts of the Arctic are 20C above normal   :o

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NeilT

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Re: The 2016/2017 freezing season
« Reply #462 on: October 31, 2016, 11:25:50 PM »
This is not albedo-driven warming

Would this be a good time to go back and look at the historical CO2 levels for the years we're trying to compare and also look at what methane is doing?

Back in 2006 it was, fully, 22ppm lower in CO2, in August, than it was in 2016.  In 1996 it was fully 55ppm CO2 lower than it was in August 2016.

When AMEG started it's dire warnings about the catastrophic Methane driven warming in the Arctic, they were warning about highs of 1900ppb methane levels being recorded.

Methane levels in the Arctic in October 2016 were up at 2400ppb.

Taking a step back and looking at it.  With the same input forcing, if we were _not_ seeing catastrophic changes in ice melt, ice re-freeze and in anomalously high temperatures at the  beginning of winter;  it would negate the entire premise of carbon driven warming.

Comparing ice volume and melt and re-freeze with 1996, when there was 55ppm less CO2 in the atmosphere (globally), should not be possible; without being able to derive the additional ice melt required to balance the temperature increase of that much heat sequestration.

Once we have analysed the 1996 figures with the ice melt capability and heat sequestration of 55ppm CO2 and 20 years of additional warming as that CO2 grew, it should then be possible to work out if 2016 was an anomalous year (outlier), or just an expected consequence of CO2 and methane driven warming.

Well that's my thinking anyway.

Of course I'm not clever enough to do the math. I'm not even sure that a model exists to calculate that specific outcome.  What I am sure of is that 50 years from now science will know exactly what happened, how it happened and what drove it.  All from clear observations and the end result of the experiment humanity is carrying out with the gas balance of the atmosphere.



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jdallen

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Re: The 2016/2017 freezing season
« Reply #463 on: November 01, 2016, 12:13:46 AM »
This is not albedo-driven warming

Would this be a good time to go back and look at the historical CO2 levels for the years we're trying to compare and also look at what methane is doing?
<snippage>
Taking a step back and looking at it.  With the same input forcing, if we were _not_ seeing catastrophic changes in ice melt, ice re-freeze and in anomalously high temperatures at the  beginning of winter;  it would negate the entire premise of carbon driven warming.
<more snippage>

I think there is no question that a lot of what we see this year is the culmination of many decades of incremental change in the global heat budget and atmospheric circulation, and I expect that in part is Jai's point.

On the other hand, the last few years have provided us with a cornucopia of unanticipated feedbacks and accelerations.  To speak to some other folks points, I think that's where the discussion of albedo comes from.

Even then, that still is not a "prompt" phenomenon; the effects of albedo (if any) on what is happening now is a result of increased insolation uptake from last spring and early summer.  That's where the unbalance would really be felt.

So, what we are seeing is a sum of a wide range of variable but increasing forces.  I think the attached image link may provide a useful metaphor.

https://farm1.staticflickr.com/339/19361016472_83bb01214d_o.gif
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Tigertown

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Re: The 2016/2017 freezing season
« Reply #464 on: November 01, 2016, 04:08:48 AM »
                  The oceans have been absorbing about 93% of all globally accumulated heat since about 1971. They absorbed heat before that but not at that rate. The rate has changed over the years, with the most recent rate being about   1022 total joules accumulated each year for all the oceans. At a variable rate per year and some difference in opinion as to what year to start counting and absorption varying between 0.5 watts per meter and 1.0 watts per meter, we get a good ballpark estimate. This adds up because the oceans take up 360,600,000 km2 and has a volume of roughly 1,334,900,000 km3 total water. Mind boggling to me. An astronomical amount of heat has been stored in the oceans over the last several decades. Thanks to the MOC, this heat has been redistributed from the tropics to the poles.


« Last Edit: November 01, 2016, 05:09:15 AM by Tigertown »
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jai mitchell

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Re: The 2016/2017 freezing season
« Reply #465 on: November 01, 2016, 05:53:32 AM »
                  The oceans have been absorbing about 93% of all globally accumulated heat since about 1971. They absorbed heat before that but not at that rate. The rate has changed over the years, with the most recent rate being about   1022 total joules accumulated each year for all the oceans. At a variable rate per year and some difference in opinion as to what year to start counting and absorption varying between 0.5 watts per meter and 1.0 watts per meter, we get a good ballpark estimate. This adds up because the oceans take up 360,600,000 km2 and has a volume of roughly 1,334,900,000 km3 total water. Mind boggling to me. An astronomical amount of heat has been stored in the oceans over the last several decades. Thanks to the MOC, this heat has been redistributed from the tropics to the poles.

This is based on multiple assessments of ocean heat data but the most recent iteration of arctic warmth involves rapidly increased meridional transport of atmospheric heat to the poles.
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seaicesailor

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Re: The 2016/2017 freezing season
« Reply #466 on: November 01, 2016, 07:17:54 AM »
Parts of the Arctic are 20C above normal   :o


I disagree with what you said before and this map you show is the argument I have. The current weather pattern is enabling all this Arctic heat release, and the heat being released was sun radiation absorbed in spring and summer, plus whatever came from direct ocean input before and during the season.
There is a big pulse of Bering inflow associated with it. Otherwise, this weather pattern is the one you would really want to alleviate the extreme overheating of the Arctic. I mean, the heat is going to the place where the planet can best get rid of it.
I am not convinced this will be too relevant for next season if weather comes warm, what really makes a difference is the lack of thick ice and multi year ice and the global warming in the background. Another early warm spring in the Northern Hemisphere and 2017 may simply go lower than 2016 and 2012.

Sleepy

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Re: The 2016/2017 freezing season
« Reply #467 on: November 01, 2016, 07:24:43 AM »
Lookalikes on the 5:th of November at 10mb.

jdallen

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Re: The 2016/2017 freezing season
« Reply #468 on: November 01, 2016, 09:10:20 AM »
Parts of the Arctic are 20C above normal   :o
I disagree with what you said before and this map you show is the argument I have. The current weather pattern is enabling all this Arctic heat release, and the heat being released was sun radiation absorbed in spring and summer, plus whatever came from direct ocean input before and during the season.
There is a big pulse of Bering inflow associated with it. Otherwise, this weather pattern is the one you would really want to alleviate the extreme overheating of the Arctic. I mean, the heat is going to the place where the planet can best get rid of it.
I am not convinced this will be too relevant for next season if weather comes warm, what really makes a difference is the lack of thick ice and multi year ice and the global warming in the background. Another early warm spring in the Northern Hemisphere and 2017 may simply go lower than 2016 and 2012.
A few thoughts.

The first is, without imported heat, the top layers of ocean in the peripheral seas would have started freezing over weeks ago.  The rate of loss I think would have been sufficient to cool the top few meters sufficiently that we'd see a cap form; perhaps not thick, but ice none the less.

I don't think the Arctic ocean and peripheral seas are really losing that much heat.  I'd love to see this image *if* it weren't for the fact all of that heat is coming via imported moisture from lower latitudes.  Now doubt "superheated" (1-4C SST's in some places...) peripheral seas are contributing, but not as much as what is being imported.

Lastly, cloud cover and precipitation.  There's a lot of it, and I don't think its home grown.  Again, this is energy being swept into the arctic from further south.
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slow wing

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Re: The 2016/2017 freezing season
« Reply #469 on: November 01, 2016, 09:38:10 AM »
Agree, jdallen.

Another factor - as pointed out by A-Team in his terrific post - is the cloud cover minimizes the radiative heat loss from the ocean surface into space, which would presumably otherwise be the dominant heat loss mechanism at this time of year.

  On the Pacific side of the Arctic basin, that weather pattern is forecast to continue at least for the next few days, though with weakening winds.

  On the Atlantic side, the forecast is for the high pressure system that is currently on the Arctic side of Greenland to drift southwards. I'm guessing that will bring clear skies to help cool the water near the ice pack edge and so allow the ice pack to expand somewhat more quickly on the Atlantic side. There are lots of unknowns though - at least to me - in the relative importance of the various heat flows and reservoirs - and there appears to be a lot more heat this year than usual in the surface water near the Atlantic sea ice edge - so we will see what happens.

BenB

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Re: The 2016/2017 freezing season
« Reply #470 on: November 01, 2016, 10:42:59 AM »
More on Svalbard (in Norwegian):

http://www.yr.no/artikkel/svalbard-pa-vei-mot-solid-varmerekord-for-2016-1.13199881

Basically, the 2016 calendar year is very likely to be record warm, there will be a record low number of frost days, October experienced record high rainfall and the climate is visibly and rapidly changing.

The average temperature in October came in at plus 3.2 °C, against an average of minus 5.5 °C, and over the past 12 months temperatures averaged -0.4 °C, over six degrees above the average of -6.7 °C.

JayW

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Re: The 2016/2017 freezing season
« Reply #471 on: November 01, 2016, 11:57:20 AM »
Attachment 1 is an animation of the last 7 days using SUOMI VIIRS I05 images. Basically centered on the Alaska.

http://feeder.gina.alaska.edu/search?utf8=✓&search%5Bsensors%5D%5B3%5D=1&search%5Bfeeds%5D%5B16%5D=1&search%5Bfeeds%5D%5B1%5D=1&search%5Bfeeds%5D%5B15%5D=1&search%5Bfeeds%5D%5B17%5D=1&search%5Bfeeds%5D%5B3%5D=1&search%5Bfeeds%5D%5B18%5D=1&search%5Bfeeds%5D%5B10%5D=1&search%5Bfeeds%5D%5B11%5D=1&search%5Bfeeds%5D%5B9%5D=1&search%5Bfeeds%5D%5B8%5D=1&search%5Bfeeds%5D%5B12%5D=1&search%5Bfeeds%5D%5B13%5D=1&search%5Bfeeds%5D%5B14%5D=1&search%5Bfeeds%5D%5B6%5D=1&search%5Bfeeds%5D%5B5%5D=1&search%5Bstart%5D=&search%5Bend%5D=&commit=Search

  It's my attempt at a water vapor loop and show the weather over the last week.  The dark areas are generally where the densest clouds are, white areas generally are cloud free. 


Second attachment is the same shot, just 3 different channels to illustrate what the dark and light areas actually show. Let others interpret what's going on.  I have my thoughts  :)  edit: it goes I05 to landcover to truecolor.
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dnem

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Re: The 2016/2017 freezing season
« Reply #472 on: November 01, 2016, 03:43:11 PM »
There has been a tremendous amount of interesting discussion recently about the source, fate and impact of extra heat in the arctic across this, the IJIS and the "Home brew AMSR2 extent & area calculation" threads.

The unknowns include:
Is the extra heat in the arctic exogenous (imported from lower latitudes) or endogenous (albedo-related or upwelled from warmer water at depth or both)?
Are the current anomalously high air temps "good" (venting heat from the system to be lost to space) or "bad" (indicative of the import of exogenous heat)?
Is low SIE "good" (allows venting of heat from the water) or bad (slow freeze season will lead to fast/big next melt season)

To me, asking if the current low SIE is good or bad rather begs the question.  Obviously an arctic covered in ice and then blanketed in snow does reduce the loss of oceanic heat.  But it also prevents storms from mixing the water column and keeps the heat safely at depth ("We've ALWAYS had enough heat in the arctic to met all the ice").

So it is both: low SIE must be allowing heat out of the ocean, but it appears to meeting exogenous heat and increased water vapor in the atmosphere so it is not really an efficient means of truly venting heat out of the system.  It also allows summer insolation to warm the ocean and storms to mix warmer waters at depth to the surface.

Similarly with respect to the source of the heat: it is both.  If there was really always enough heat in the arctic to melt the ice, more of that MUST be coming in contact with the ice due to enhanced mixing.  And it strains credulity to suggest that there are not meaningful quantities of exogenous heat entering the system through both oceanic (see A-Team's brilliant post #435) and atmospheric routes.

So to sum up, I would conclude that large and excess quantities of both exogenous and endogenous heat are present in the arctic.  Some of this heat is escaping the ocean due to mixing and low SIE where it is encountering a warmer and wetter atmosphere.  Perhaps more is escaping the system to space than before the presence of all this excess heat, but I can't imagine that it is anywhere near enough to come close to balancing the equation. 

SIE is at an all-time low and is more vulnerable than at any time perhaps in the history of the human species to a run of good but not exceptional melting weather leading to a blue ocean event in the arctic.








epiphyte

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Re: The 2016/2017 freezing season
« Reply #473 on: November 01, 2016, 03:53:50 PM »
As of late October 2016, large areas of open water remain in the Beaufort, Chukchi, Bering Straits, and East Siberian Sea. The peripheral surface waters are far too warm for ice to stably form — in places some 4º C above the freezing point (-1.9º at surface salinity) — except in the eastern Beaufort and Laptev seas.

The Beaufort, Chukchi and Barents seas are seasonally ice-free now, with all that that implies. We need not wait until 2050, it’s here now. The Beaufort had significant areas of open water by the 1st of May this year and still has not frozen over six months later.

This development in the Chukchi is primarily attributable to to long fetches of open water allowing strong winds to turbulently mix surface with lower warmer water, to large and increasing inputs of warm Pacific Water crossing the 50m x 85km sill at the Bering Strait, teleconnections of an El Nino year and Pacific blob, persistent Arctic Ocean cloud cover reflecting back radiated heat, for which the stage has been set by long term trends in sea ice loss due to global warming and its Arctic amplification.

The 55-day time series below shows sea surface temperature anomalies (SSTA) and sea surface temperature (SST) at 70º N, 170º W (green circle) and the sea ice edge response to conditions (AMSR2 zero ice concentration envelope, yellow line). Solar input has ceased; colder air temperatures are ineffectual at cooling large volumes of mixed water — the meagre heat capacity and low conductivity of air are no match for wind-mixed waters or the recent and continuing surge through the Bering Strait suggested by surface salinity data. However air temperatures themselves have been most anomalously warm, see https://twitter.com/ZLabe/status/790579202181390336

The mean October anomaly at the indicated site is 2.3º C above the average sea surface temperature of 4.3º. It’s feasible to obtain these statistics regionally (over each daily expanse of open water) using the AMSR2 mask to restrict a contoured version of the nullschool display, but probably better to retrieve the raw data product RTG-SST/NCEP/NWS or its daily contour map.

Sea ice-dependent marine mammals such as walruses reach feeding grounds by resting on floes carried by wind and current; an embedded sub-animation shows a walrus shaking its head as it fades to near-oblivion on the final frame. On October 24th, the nearest ice to Barrow AK was 448 km to the north. The first few kilometers of that gray/pancake/underwater frazil ice would not support the weight of a gerbil.

Indeed the Arctic Ocean has not frozen north of Svalbard either, which is 730 km farther north than Barrow and just 1050 km from the north pole. The issues here are different for the Barents though, involving the Atlantic Water currents and a close-in continental shelf.

The Arctic Ocean does not need a ‘black swan’ event any more to fall catastrophically below its trend line, a gray swan event will do. That’s weather conditions well within normal variation but ill-timed: sunny weather during early melt season, strong cyclones in August, persistent warm and humid air brought in by lower latitude hurricanes, steady pressure dipoles whose winds expors ice out the Fram, and so on. Here the black swan of September morphs to white by the end of October to represent the Chukchi and Bering Straits are not freezing up as in the past (3rd and 4th animations).

Some very recent scientific articles describe the currents and heat inputs across the Bering Strait and analyse the satellite record in this area. Note though that an article published in October 2016 will have a data cutoff of 2014, but the 37 abstracts at this December’s AGU2016 mentioning the Chukchi or Beaufort bring these up to date..

Emerging trends in the sea state of the Beaufort and Chukchi seas
J Thomson et al  http://dx.doi.org/10.1016/j.ocemod.2016.02.009
http://archimer.ifremer.fr/doc/00345/45590/45202.pdf free full text

The sea state of the Beaufort and Chukchi seas is controlled by the wind forcing and the amount of ice-free water available to generate surface waves. Clear trends in the annual duration of the open water season and in the extent of the seasonal sea ice minimum suggest that the sea state [ie waves] should be increasing, independent of changes in the wind forcing…. The increase in wave energy may affect both the coastal zones and the remaining summer ice pack, as well as delay the autumn ice-edge advance [to the extent waves hit the edge].

A Synthesis of Year-Round Interdisciplinary Mooring Measurements in the Bering Strait (1990–2014)
RA Woodgate et al
Oceanography | September 2015
http://tos.org/oceanography/assets/docs/28-3_woodgate.pdf  free full text

Although the volume transport of the Alaskan Coastal Current (ACC) of  ~0.1 Sv is small compared to the full Bering Strait throughflow of ~0.8 Sv [which in turn is a quarter of Atlantic Waters entering at the Barents at 3.2 Sv],  the ACC is 5ºC warmer and 7 psu fresher than the main waters of the strait, it carries a third of the heat and onequarter of the freshwater flux of the Bering Strait.

Perhaps most dramatic interannual variability is the increase in Bering Strait volume flux from 2001 to 2013 from ~0.7 Sv to ~1.1 Sv, almost a 50% increase in the flow. Since to first order whatever enters the Bering Strait must exit the Chukchi Sea into the Arctic Ocean, this increases ventilation of the Arctic halocline, decreases residence time in the Chukchi by several months, and increases oceanic heat flux.

Since Pacific waters exit the Arctic via the Fram Strait and the CAA at near-freezing temperatures, this allows us to quantify the heat lost from the Pacific waters somewhere in the Chukchi/Arctic system. Including corrections for the ACC and stratification, calendar-mean Bering Strait heat fluxes are 3 6 x 1020 J/ yr 1 (or 10 -20 TW,  comparable to  shortwave solar input to the Chukchi Sea.

This quantity of heat is sufficient to melt 1-2 million square km of 1 m thick ice. Bering Strait heat flux may act as a trigger to create open water upon which the ice albedo feedback can act, and also provides a year-round subsurface source of heat potentially thinning Arctic sea ice, since Pacific summer waters are found in half the Arctic Ocean.

Variability, trends, and predictability of seasonal sea ice retreat and advance in the Chukchi Sea
MC Serreze, AD Crawford, JC Stroeve, AP Barrett, RA Woodgate
J. Geophys. Res. Oceans,121, doi:10.1002/2016JC011977 (2016) blocked access, figures available

As assessed over the period 1979–2014, the date that sea ice retreats to the shelf break (150 m contour) of the Chukchi Sea has a linear trend of 20.7 days per year. The date of seasonal ice advance back tothe shelf break has a steeper trend of about 11.5 days per year, together yielding an increase in the open water period of 80 days.

Based on detrended time series, we ask how inter-annual variability in advance and retreat dates relate to various forcing parameters including radiation fluxes, temperature and wind, and the oceanic heat inflow through the Bering Strait (from in situ moorings). Of all variables considered, the retreat date is most strongly correlated with the April through June Bering Strait heat inflow. Predictability will likely always be limited by the chaotic nature of atmospheric circulation patterns.

Enhanced heat fluxes from the ocean back to the atmosphere in autumn and winter is a major driver of Arctic amplification — the outsized rise in Arctic surface air temperatures relative to the rest of the planet. Whether the effect of ice loss on Arctic amplification extends through a deep enough layer of the troposphere to alter jet stream patterns with impacts on middle-latitude weather is a vibrant area of debate.

GC24A-01: Sea State and Boundary Layer Physics in the Emerging Arctic Ocean
Tuesday, 13 December 2016 Moscone West - 3005

The sea state of the Arctic Ocean is changing. With an increasing retreat of sea ice in the summer months, storms are now more likely to occur over open water, and the result is an increasing trend in both the heights and periods of surface waves in the Chukchi and Beaufort Seas. The elevated sea state affects, in turn, the refreezing process in the autumn. In 2015, a field campaign collected a comprehensive suite of air-ice-ocean measurements during the autumn freeze-up in the Beaufort Sea, and these measurements are used to investigate the surface wave effects and coupled dynamics.

The most prominent process is the formation of pancake ice, which occurs when surface wave motions disturb newly forming frazil ice. Analysis of a wave event from open water through different stages of a gradually maturing pancake ice cover shows high sensitivity of the surface waves to the types of ice cover. Other cases suggest that waves impact the near-surface heat flux convergence, impacting the ice formation. Hence, there is a two-way interaction between ice and waves. Wave attenuation is captured with adjustment of a viscoelastic parameterization in a wave hindcast model. The results suggest that a fully coupled air-ice-wave model will be necessary to describe the evolution of sea state and ice cover during the Arctic freeze-up.

C31D-02: Regional Upper Ocean Variability and Ocean Heat Losses during the 2015 Autumn Ice-Edge Advance in the Chukchi and Beaufort Seas as Observed during the Sea State Field Campaign
Wednesday, 14 December 2016 Moscone West

Some of the fastest Arctic sea ice changes are happening in the Chukchi and Beaufort Seas as indicated by a much earlier (by ~49 days over the last 36 years) ice-edge retreat in spring, followed by a much later (by ~43 days) ice-edge advance in autumn (based on 1979-2014 satellite observations). The lengthening of the summer open water season and increasing fetch also mean greater upper ocean heat content and a longer, possibly stronger period of wind/wave forcing on the upper ocean and advancing sea ice cover.

To understand how surface waves and winds affect air-sea-ice interactions and consequently the timing of the autumn ice-edge advance in the emerging Arctic, a Sea State field campaign was conducted aboard NSF’s R/V Sikuliaq from 4 Oct to 5 Nov 2015. During the campaign we obtained contemporaneous in situ observations of the atmospheric boundary layer, ice cover, wave state and upper ocean along a cruise track in and out of the advancing ice cover in the Chukchi and Beaufort Seas. Vessel-underway (uCTD) profiler was used to collect over 4200 upper ocean profiles during both quiescent and stormy conditions in and outside the ice cover.

Using the uCTD data we describe the spatial variability in upper ocean structure and heat content within the context of its recent past regarding summer open water duration and wind/wave forcing, as well as regional variability in water mass characteristics. We then describe the contemporaneous air-sea-ice observations, including air-ocean energy fluxes and changes in upper ocean heat content during brief periods of ice-edge advance, loitering and retreat to explain the overall space/time evolution of the ice-edge advance in the Chukchi and Beaufort Seas during autumn 2015.

A-Team, I can't imagine how someone with your talent for distilling vivid meaning from dry data can possibly afford to spend so much time enlightening the members of this forum - thank you so much for your work. I do hope you're looking into ways to expose it to a much larger audience - You paint the sort of pictures that can do more than say a thousand words... they can refute a thousand lies.

jai mitchell

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Re: The 2016/2017 freezing season
« Reply #474 on: November 01, 2016, 04:48:12 PM »
Dnem,

well said.

The amount of relative atmospheric vs. ocean exogenous heat is about 100:1

current snow cover anomalies in the northern hemisphere are at a new record, there is no residual albedo warming that is coming from the land.  It is all mid-latitude warmth.  A further discovery of the rapidly expanding Hadley Cell in the mid-latitudes is additional indication of the loss of the arctic 'backstop' that allows for rapid expansion of the 30'N desert zone (as well as imported heat from the tropics to mid latitudes)

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wili

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Re: The 2016/2017 freezing season
« Reply #475 on: November 01, 2016, 08:56:29 PM »
dnem wrote:

"Is the extra heat in the arctic exogenous (imported from lower latitudes) or endogenous (albedo-related or upwelled from warmer water at depth or both)?"

Wherever the heat is originating from, is it being held close to the surface more than it has in the past because of increases in water vapor in the region due to the long and late and widespread ice free areas of the Arctic Ocean?
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Watching_from_Canberra

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Re: The 2016/2017 freezing season
« Reply #476 on: November 01, 2016, 09:44:16 PM »
The unknowns include:
Is the extra heat in the arctic exogenous (imported from lower latitudes) or endogenous (albedo-related or upwelled from warmer water at depth or both)?

Either way, it must be resulting from more heat in the system as a whole.  Unless, of course, it's anomalously cold somewhere else?

jai mitchell

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Re: The 2016/2017 freezing season
« Reply #477 on: November 01, 2016, 10:13:08 PM »
Compare Nov 1, 2013 to today
at 850 mb height (about 1,500 meters)

there is about 230% more water vapor at the north pole and the temperature is 9C warmer

Note, the common definition of "arctic air" is an 850mb height with temperatures below 20C  --> https://www.wunderground.com/blog/24hourprof/arctic-air-masses

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Ice Shieldz

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Re: The 2016/2017 freezing season
« Reply #478 on: November 01, 2016, 11:27:22 PM »
Consider that the arctic has been shedding sea ice at an average annual rate of 13,500 square miles (35,000 square kilometers) since 1979, the equivalent of losing an area larger than the state of Maryland every year.  Given the accumulating effect of this, in terms of increasing area of insolation, one could clearly see how oceanic heating momentum can really build, especially with the additional forcing related to the multi-year trend of staggering increases in arctic air temps, and exogenous moisture influxes, both of these additively block the oceanic heat from escaping.

With this in mind, what if we look at the arctic oceanic heat content as the primary index for a kind of persistent multi-year Arctic El Nino, that fluctuates year to year but maintains a clear trend of heating toward an ever-warmer Nino state?  The westerly wind bursts that push oceanic heat east to create Nino conditions in the central/eastern Pacific are somewhat equivalent to the exogenous atmospheric winds that bring moisture and heat into the arctic - but instead of causing the advection of oceanic heat equatorially across thousand of miles of ocean, they advect atmospheric heat medorinally across thousands of miles of atmosphere.  Of course, as A-Team's points out in his excellent post, the amount of heat advected by ocean currents far exceeds that which the atmosphere advects.  However, our arctic nino atmospheric winds ekman pump up significant heat from depth while weakening the halocline.

All of this helps set into motion a feedback mechanism where warming SSTs (particularly in the Barents-Kara seas) can split the polar vortex and slow/disrupt the jet stream, which in turn allow in more heat, winds and moisture that further increase SSTs.  The corollary in tropical nino exists in how warming equatorial SSTs feedback into the Walker cell, causing it to grow more westerly wind bursts which in turn create even higher SSTs.  With tropical nino we have the vastly deep pacific ocean that comes into play to help reverse the amplification of the Walker cell by absorbing extra upper-ocean heat via the nina half of the oscillation.  Unfortunately, in the Arctic we don't seem to have such an oscillation or buffer, so there is no stoping the train :0

To summarize, I think the oceanic-heat content in the arctic has reached a state where the momentum of its extraordinary heating due to insolation is now more fully expressing itself via the help of medorinal atmospheric transport and advection.  Going forward it seems clear to me that the arctic nino will become the main player in climate changes with the tropical nino feeding into its intensity while also increasing net enthalpy of the earth's climate system primarily by putting more moisture into the atmosphere and thereby trapping more heat.

The following data is for anyone who wants to explore the math around the insolation-derived energy gains in the Arctic/Planetary energy budget - given the average annual 35,000 square kilometers extent loss since 1979.

Amount of Solar Energy Received Per Day - Per Unit Area by Season and Latitude
« Last Edit: November 02, 2016, 12:00:59 AM by Ice Shieldz »

slow wing

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Re: The 2016/2017 freezing season
« Reply #479 on: November 02, 2016, 04:14:57 AM »
From Neven's comparison page, https://sites.google.com/site/arcticseaicegraphs/concentration-maps/sic1101, this year has a lot more blue water on the Pacific side of the Arctic Basin than on any other 01 November in the satellite record:

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Re: The 2016/2017 freezing season
« Reply #480 on: November 02, 2016, 06:11:20 AM »
Cross posted this because of the importance.

As ocean temps rise, the Arctic will be affected more and more. An army of 3800 robots that can dive and drift and dive again, and then float back to the surface and communicate via satellite could really help understand how the oceans are warming. A program called Argo is already doing just that.

"....and the appointed time came for God to bring to ruin those ruining the earth." Revelation 11:18.

slow wing

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Re: The 2016/2017 freezing season
« Reply #481 on: November 02, 2016, 07:16:06 AM »
Agree, Tigertown, that it is vitally important to deploy more buoys &/or robot divers to better characterise the air, ice, snow and water parameters throughout the Arctic Basin.


This topic has been discussed in some detail on the "What the Buoys are Telling" thread, beginning with http://forum.arctic-sea-ice.net/index.php/topic,327.msg90613.html#msg90613 (#1184).

See, in particular,
http://forum.arctic-sea-ice.net/index.php/topic,327.msg90678.html#msg90678 (#1194 - on the Argo program you refer to).


Yes, a large-scale program such as this should definitely be implemented by next year's melt season!

Is there anyone on here who can assist in making this happen?  :)

Anyone in the Argo collaboration who knows of Argo's Arctic plans? Can push for more monitoring there?
« Last Edit: November 02, 2016, 07:23:22 AM by slow wing »

Pmt111500

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Re: The 2016/2017 freezing season
« Reply #482 on: November 02, 2016, 01:01:06 PM »
Light winds from the Atlantic side cross the Pole, picked up -1,8C from 87,5N, c. 155 miles from pole. Most cold winds go down to Siberia splaining some of the snow anomaly.
« Last Edit: November 02, 2016, 01:37:12 PM by Pmt111500 »

Tigertown

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Re: The 2016/2017 freezing season
« Reply #483 on: November 02, 2016, 02:21:47 PM »
Agree, Tigertown, that it is vitally important to deploy more buoys &/or robot divers to better characterise the air, ice, snow and water parameters throughout the Arctic Basin.


This topic has been discussed in some detail on the "What the Buoys are Telling" thread, beginning with


Yes, a large-scale program such as this should definitely be implemented by next year's melt season!

Is there anyone on here who can assist in making this happen?  :)

Anyone in the Argo collaboration who knows of Argo's Arctic plans? Can push for more monitoring there?

Sorry, didn't find your post there when I did a search prior to posting.

I don't know if there are plans to expand the program or not, but as the system is, a good deal can be learned about the heat that is reaching great depths and the currents carrying the heat to the Arctic and Antarctic.
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Re: The 2016/2017 freezing season
« Reply #484 on: November 02, 2016, 02:22:44 PM »


2012 didn't show much abnormal temperatures: it was a true anomalie shall we say!



2016, if you check the temp records at dmi for past 80N, are wacko in comparison to all other years.

Curious factors are emerging.... something must bind them however.

Should we just call it advection???
(I should possibly modify my comment by saying 2007



shares a common path in the latter days yet the preconditioning seems quite different,... obviously 2012 is wacked tho!)

 (2009 also seems close...)
« Last Edit: November 02, 2016, 03:18:03 PM by abbottisgone »
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Re: The 2016/2017 freezing season
« Reply #485 on: November 02, 2016, 02:24:19 PM »
Do we know if the degree day freezing / degree day thawing charts from the late Andrew Slater's site will be updated - or replicated ?

With the recent high temps they would be an interesting graphic.

http://cires1.colorado.edu/~aslater/ARCTIC_TAIR/

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Re: The 2016/2017 freezing season
« Reply #486 on: November 02, 2016, 03:08:52 PM »
slow wing: may I say that wrangel island seems to be the pinch point?
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Re: The 2016/2017 freezing season
« Reply #487 on: November 02, 2016, 06:33:49 PM »
Hat tip to Colorado Bob for finding this.  Reposted link from Neven's blog:

http://onlinelibrary.wiley.com/wol1/doi/10.1002/2016GL070526/abstract
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Re: The 2016/2017 freezing season
« Reply #488 on: November 02, 2016, 06:35:21 PM »
Do we know if the degree day freezing / degree day thawing charts from the late Andrew Slater's site will be updated - or replicated ?

With the recent high temps they would be an interesting graphic.

http://cires1.colorado.edu/~aslater/ARCTIC_TAIR/
If we can get access to his data and on-going changes, I think any one of a number of us here can sort out how to do that.  I'm also sure any number of us would be interested in seeing that.
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Re: The 2016/2017 freezing season
« Reply #489 on: November 02, 2016, 06:58:18 PM »
Hat tip to Colorado Bob for finding this.  Reposted link from Neven's blog:

http://onlinelibrary.wiley.com/wol1/doi/10.1002/2016GL070526/abstract

And thanks jdallen for bringing the link here. I've reduced the number of sites I follow intensely reading most comments too so might have missed this one. This looks like what's up in the 2040s if not earlier.

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Re: The 2016/2017 freezing season
« Reply #490 on: November 02, 2016, 09:41:14 PM »


This is getting progressively worse…

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Re: The 2016/2017 freezing season
« Reply #491 on: November 02, 2016, 09:55:29 PM »
I can't believe that thing went up again. The current temperatures are  September temperatures. What's next, melting? Has that happened before, in November?
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Archimid

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Re: The 2016/2017 freezing season
« Reply #492 on: November 02, 2016, 10:06:13 PM »
In 1996 there was a somewhat similar jump. Here is the temperatures and sea extent for 1996.
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Re: The 2016/2017 freezing season
« Reply #493 on: November 02, 2016, 10:33:49 PM »
Yes, Arch,

But that 'jump' appeared on the background of some already steady freeze during October. This time, good ice-producing freeze has been limited to a few days until now.
And the DMI graph tells us little about the situation in the Beaufort-, Chukchi and ESS seas.
The 'no refreeze' anomaly out there parallels North of 80 degrees temperature weirdness.

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Re: The 2016/2017 freezing season
« Reply #494 on: November 02, 2016, 10:52:49 PM »
That DMI graph is only for >80 degrees N, that is, a 10-degree circle around the North Pole.

The temperature bumps in the graph come from weather patterns that are easily identified from looking at nullschool:
https://earth.nullschool.net/#current/wind/surface/level/overlay=temp/orthographic=-35.44,93.43,1444

The current bump is due to warmer southerly winds heading into the 10-degree circle from Svalbard and through the Fram Strait. The nullschool screenshot has has already been posted above at #482
http://forum.arctic-sea-ice.net/index.php/topic,1611.msg92869.html#msg92869

Nullschool also displays the current temperatures in, e.g., the Beaufort-, Chukchi and ESS seas.

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Re: The 2016/2017 freezing season
« Reply #495 on: November 02, 2016, 10:56:10 PM »
All too true werther. I just needed some kind of context and that's the best I found.

In 1996, from Nov 1 to maximum extent the ice grew about 5.8 Mkm2. If this season followed the same pattern of growth that would put this year maximum at 12.9 Mkm2. Record low by 1.2Mkm2.

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Re: The 2016/2017 freezing season
« Reply #496 on: November 02, 2016, 11:29:19 PM »
Here we are in November still sailing into uncharted waters in the peripheral seas of the Arctic Ocean.

This post provides a quantitative summary of the open water situation for the Chukchi, Beaufort and East Siberian seas from 01 April - 01 Nov 2016 with an eye to calculating solar energy absorbed by open water (not ice) during the last seven months.

The future has arrived for these regions of the Arctic (not mention the Barents) — they’re already ‘open seasonally’ (75% of potential maximal area, 3 months or more of summer heating season).

A newspaper article last week in the WaPo quotes scientists to the effect “it doesn’t count” unless the Arctic Ocean is 100% open 100% of the year, not to worry until 2100 if even then.

That is a terrible misunderstanding. The Arctic is already failing regionally at its job of planetary refrigerator:

The first image below shows the expanded study area relative to the Chukchi as defined by  Serreze et al 2016. It lies north of the Bering Strait, bounded by the 150º E (nicking the New Siberian Islands), to the east by 120º W (taking in the Beaufort Gyre at Banks Island) and to the north by the 75th parallel (incorporating the 150 m continental shelf isobath).

Perovitch measured solar energy received on the ground in the central Beaufort for the entire 1998 season, some 92% of this energy is absorbed by open water; Serreze et al provide a very accurate measurement of Chukchi WGS84 area which is fully transferable to high resolution UHH AMSR2 determinations of daily ice edge, as explained in the lower right of the figure.

The second image shows that solar input peaks as expected on the solstice (wavy red line, w/m2 scale on right) but varies greatly according to cloud cover. Open water in this area peaks considerably later (blue bars, millions of km2 scale on left). Consequently, solar heat absorbed by open water (sum of daily product of solar input x open water) reaches its maximum at an intermediate time (regularized yellow curve, area underneath representing total heat input). Here however we don’t know how cloudiness in 2016 compared to the year of measurement.

As the Arctic hasn’t had significant solar input for months, clearly solar cannot immediately explain the current open water anomaly — the massive and unexpected delay of refreezing which shows no sign of abating. However it’s very difficult to disentangle all the feedback processes and their phasing in the solar, ocean, atmosphere and ice system.

The animation runs for 215 days. Land is blocked out as yellow, CAA and Aleutian waters are light blue (not considered), and the central Arctic is grayed out. Ice concentrations are retained (blue to white). Only the darkest blue (zero sea ice concentration) is considered open water during the pixel counting process and conversion to area. These conventions are necessary to reduce file size to within forum bounds. The attached spreadsheet txt file provides the raw data used to make the graphs. [Despite that, so far forum software declines to load it...]
« Last Edit: November 02, 2016, 11:36:32 PM by A-Team »

oren

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Re: The 2016/2017 freezing season
« Reply #497 on: November 02, 2016, 11:36:28 PM »
Looking at my favorite extent forecast source - the regional amsr2 graphs - most seas reach full extent during the winter peak regardless of what went on during refreeze. These include the Kara, ESS, Hudson, Beaufort and Chukchi, the CAA and the CAB of course. Others reach the same typical extent during peak season, these include the Greenland Sea and Baffin. This means that extent records are mostly set on the Barents, Bering and especially Okhotsk, where the numbers seem somewhat random and therefore hard to predict. I wouldn't count on this season to produce a record low extent by a large margin. On the other hand, I would expect record low thickness/volume (and record high ice salinity) by a significant margin due to the lateness and weakness of the refreeze season. This may or may not show up on PIOMAS, but will almost certainly affect the 2017 melting season.

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Re: The 2016/2017 freezing season
« Reply #498 on: November 02, 2016, 11:45:27 PM »
Looking at my favorite extent forecast source - the regional amsr2 graphs - most seas reach full extent during the winter peak regardless of what went on during refreeze. These include the Kara, ESS, Hudson, Beaufort and Chukchi, the CAA and the CAB of course. Others reach the same typical extent during peak season, these include the Greenland Sea and Baffin. This means that extent records are mostly set on the Barents, Bering and especially Okhotsk, where the numbers seem somewhat random and therefore hard to predict. I wouldn't count on this season to produce a record low extent by a large margin. On the other hand, I would expect record low thickness/volume (and record high ice salinity) by a significant margin due to the lateness and weakness of the refreeze season. This may or may not show up on PIOMAS, but will almost certainly affect the 2017 melting season.

Historically the peak extent has not had much variation, it's true.  Watching the 2012 refreeze was quite interesting, as it rapidly moved towards the normal.

But the question is if this is really an atypical year where the current amount of open water makes a difference that persists in some way into the next year.

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Re: The 2016/2017 freezing season
« Reply #499 on: November 03, 2016, 12:23:01 AM »
Thank you A-team .. my ringside seat just gets better and better .Your ballet of ice has me mesmerised !
The last few frames help show the damage being done to the ice by the recent and current weather .. 
and another last hurra ! for big block :)
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