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Messages - jdallen

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1
Arctic sea ice / Re: 365 day average extent poll
« on: January 23, 2020, 12:07:01 AM »
I'm going to call it - the majority of us, myself included, were probably wrong. I think there's too much ground to make up in the next two months with recent gains.
Now the actual fun starts - dissecting why, and what additional factors we should be examining in making our predictions.

2
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: January 22, 2020, 10:10:12 PM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 21st, 2020:
     13,332,633 km2, an increase of 40,141 km2.
     2020 is 11th lowest on record.
     In the graph are the today's 15 lowest years.
     Highlighted the 4 years with September lowest min (2012, 2019, 2016, 2007) & 2020.

Interesting statistical bit to note - the 6th through 15th years on that chart lie in a band only 250k km2 wide, with 2020 right about square in the middle of it.  Still deciding what meaning it has to over all system behavior.

3
Arctic sea ice / Re: The 2019/2020 freezing season
« on: November 14, 2019, 07:46:13 AM »
I've been away for a few days and man, what an unbalanced refreeze.

That said, the lack of refreeze in the Chukchi and Bering I find very disturbing.  To a lesser degree I'm concerned about the Hudson and Baffin.

But the lack of ice in the Chukchi and Bering speak very strongly to what will happen next spring on the Pacific side.

4
Arctic sea ice / Re: Latest PIOMAS update (June 2019)
« on: November 04, 2019, 05:40:03 PM »
PIOMAS Volume as at 31 October 2019   6.518  km3 '000
The standard graphs and tables as I use for the JAXA extent data are attached.

Volume gain in October mostly well below average, a bit above average gain in the last week.

2019 volume is still 3rd lowest in the satellite record, by 101 km3 above 2012, and only 33 km3 above 2016, and less than 2018 by 709 km3.
_______________________________________________________________
The last table is a look at projections to the next maximum. Far too early to take it seriously.

Volume is what I will be watching most closely this season.  Already cross-referencing from the Polarstern expedition thread, we've already seen hints that we may have been overestimating it.

5
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 04, 2019, 05:37:20 PM »
JAXA ARCTIC SEA ICE EXTENT :- 7,804,258 km2(November 2, 2019)

Am I seeing a persistent gradual reduction in daily extent gain, and will that reduction continue?

<snippage>
For the last 40 years sea ice decline in winter has been a lot less than in the summer. So eventually 2019 sea ice extent would play catch-up to get closer to the trend values. I did not expect it to happen this quickly.

Will these 10 days of very high extent gains continue? 
Or will extent gains return to the average or even below?

2016 as I recall had a huge spike in cyclonic activity along the east coast of both Asia and North America which I think was key in slowing the refreeze.  I think for that reason 2016 will persist as an anomaly for some time, much as 2012 has.

Absent that vigorous activity, I do think the rapid extent gains will continue over the colder near-continental seas in particular - ESS, Laptev, Kara, CAA, Hudson, and Okhotsk.  However once that real estate is used up, I think we quite possibly will see a stall as the heat content in the Pacific side in particular is so huge that even without imported heat from further south it will resist freezing and provide its own local feedbacks to slow heat loss as well.

6
When angular momentum is not conserved by parameterization in a weather model,...

HMMM. Another thought popped up... there's a whole kinetic energy dynamic that's in play here as well.  Slowing millions of km3 of atmosphere requires dumping of energy via friction loss as heat, and it's not inconsequential.  The delta vee between equator and pole is over 400 m/sec.  It may be lost over a distance of 10,000km but is far from inconsequential.

Similarly air moving south has an equivalent problem in reverse, but it's picking up kinetic energy off of the ocean or land surface, or translating it out of atmosphere it runs into moving at a different velocity.  It's an interesting illusion, as from the ground we perceive blasts of cold air roaring south, when in fact its us moving at a differential velocity slamming into that cold air which has much lower angular velocity.

But again, more energetic atmosphere means more displacement.  I wonder how that exchange of energy from velocity to heat is being managed in the models (or not, as the case may be) and what kind of heating potential it represents? 

It would be zero-sum over all, as energy dumped in the Arctic would be picked up by air masses being displaced south, but does represent another mechanism by which heat exchange is taking place.  In short, more breakouts over time reflect a decrease in gradient of net enthalpy, I'd imagine.

7
This is the 10hpa forecast as long as they make it (GFS). NO SPLIT AT ALL.

I hope your other data and musings are more exact

that's a different attribute at a different level.  no bite on the attitude.

https://www.wetterzentrale.de/en/topkarten.php?map=2&model=gfs&var=39&run=18&time=252&lid=OP&h=1&mv=0&tr=3#mapref

Posing a question, as I have no rigorous understanding as yet of the dynamics here.

Would it perhaps be implied here that there is increasing turbulence resulting in disconnections in behavior between layers of atmosphere? 

Or, if the apparent disconnections is purely coincidental, is what we are seeing evidence of increased turbulence and increased disruption of existing patterns?

8
Arctic sea ice / Re: NSIDC 2019 Arctic SIE September average: July poll
« on: October 15, 2019, 01:52:57 AM »
And not too far from our own ASIF prediction (3.75 to 4.25 million km^2).
*Dang*.

One bucket too low.

9
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: October 11, 2019, 06:35:55 AM »
jdallen:
The choice was between Hillary and the Donald.
<snippage>


And Trump is aggressively pursuing a policy that will lead to the deaths of billions this century
<snippage>

<sadly disappointed head shake>
This is by definition a question of faith(s), and impossible to argue over rationally.

Now back to the question posed by this thread...

Indeed!

<snippage>
     FWIW, the September 2019 IPCC cryosphere report shows Extent becoming asymptotic at about 10% of the 2000 level around 2070. 
<more snippage>

I've been slowly arriving at a similar conclusion, as a result of a confluence of factors we've covered all over the forums.  Key among them are total system enthalpy, ocean enthalpy, the dynamics of seasonal changes in the radiative energy budget... but other things like just the nature of ocean surface dynamics and the physical chemistry of water come in to play as well.

I think before that last 10% or so disappears for good, there will need to be a lot more support for atmospheric heating at high latitudes.  Along the way, this will create conditions for stupendous storms at much higher latitude than we've ever imagined. 

The drop off insolation at the end of the melt season will be like a vaccuum collapsing with everything rushing in to fill it.  I think we'll see more continuous flow out of the tropics all the way to the Arctic, with no Ferrel or Arctic cells to speak of long before the ice fully disappears consistently in the summer.

10
Arctic sea ice / Re: MOSAiC news
« on: October 10, 2019, 07:28:31 AM »
It's not entirely clear that melt season is over in some parts of the Arctic Ocean.
<snippage>
It's pretty clear from the temperature data, the extent/area data and the sensor data from sources like Mosaic that the transition from melt to refreeze is no where near as distinct as it was prior to the last decade or so.

We are already seeing Arctic breakouts.  Heat intrusions above 75N are continuing pretty much unabated.  I suspect Mosaic will not show signs of either significant thickening or serious expansion of the pack into the peripheral seas for quite some time.

11
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: October 10, 2019, 07:21:53 AM »
I get your point, Glen, but I vote as if my soul depends on it.
That's why this pro-life voter voted for Kasich in the Primary but Trump in the election (and hated it)>
Tom, for someone so intelligent, I have a very hard time squaring that with such complete foolishness.

He is actively working for the destruction of our environment.  How could you?

12
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 07, 2019, 08:44:40 AM »
Still trying to understand how the *warmest* August on record, according to awesome +70N 925hPa temps chart produced by Zack Labe, led to such a poor loss of ice extent. No convincing explanation so far....
I am convinced that we had normal melting conditions in 2019.

WTF? Normal melting conditions? With warmest August, 2nd warmes June and 3rd warmest July (and it was quite sunny for a good part of the summer as well)? How can you call that normal? Based on temps, ice should have crashed to nil, but it held up very well, so I have the same question as the original poster: i wonder why we did not lose more ice?

My answers are:
- the GAC of 2012 was truly a powerful and rare phenomenon and simple warm weather is not enough to repeat it
- the Central Pack is really hard to crack
- the Arctic is a mystery :)
Your answers are good, especially the third.

When the melting momentum hit a wall in early August I commented then that we were missing something key in our understanding of what drives the melt.  They key things that stand out in my mind now are:

  • Lack of comprehensive understanding of salinity, heat and movement of water under the ice
  • Underestimating the effect of high latitude and other conditions affecting refraction that reduce heat uptake.
  • Strong support for ice retention around the emerging "cold poles" - though that pretty much failed completely by July on the Siberian side.
There's far more, no doubt, but that's what jumps out at me now.

I will be watching a number of things now on the refreeze.  As others noticed, we are seeing regular cyclical massive intrusions of heat and moisture all the way into the central basin, which themselves show no sign of diminishing.

I think the refreeze of the peripheral central seas (ESS, Chukchi and Laptev in particular) will be strongly retarded.  I think the Beaufort and CAA will actually refreeze fairly fast, in keeping with the development of the "cold pole" over northern Canada and Greenland.  I think they will catch up rapidly once we reach mid to late November, and I think continued intrusions of heat will offset what would normally be heat lost from those seas.  That heat retention will play a key role in how much thickening we see late in the refreeze season.

I will be watching the CAB with considerable interest and am overjoyed by the over-winter expedition being carried out.  My prediction of what's ahead is that we will see much higher than typical snowfall, which we know is a very two edged sword.  Next spring it will protect the ice.  However, if it stacks up too high and too fast, it will seriously impede the very necessary lost of heat out of the arctic basin we need to preserve the ice.

I'm tentatively thinking were going to see conditions much like 2016-2017, with serious drops in FDD's and anemic volume growth, much of which won't happen until after northern hemisphere snowfall locks in colder temperature over the continents.

It will be an interesting season.

(Post script - various models have the remnants of typhoon HAGABIS blowing back up into a *very* powerful storm in the Bering in a few days.  That could seriously disturb weather on the Pacific side of the basin.  Worth keeping track of, I think.)

13
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 05, 2019, 09:04:11 AM »
From the extent/area data thread...
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
October 4th, 2019:
     4,534,324 km2, an increase of 18,749 km2.
     2019 is 2nd lowest on record.
     (2007, 2012 & 2016 highlighted).
Prediction, mid-October - 2019 will drop behind 2012 to become consistently lowest extent for date, and will continue to be there through most of the freezing season.  I'm expecting a warm winter in the high arctic.

14
Arctic sea ice / Re: September predictions challenge 2019
« on: October 05, 2019, 08:59:00 AM »
*That* must be what happened.  I'll take the honorary victory.

15
Arctic sea ice / Re: September predictions challenge 2019
« on: October 05, 2019, 01:49:11 AM »
Hope all the calculations are ok.
(Let me know if there is a correction to make ;) )
How did I miss the August polls?

Well, even without them, I did better 'n Average ;)

16
Arctic sea ice / Re: The 2019 melting season
« on: September 20, 2019, 09:02:10 AM »
I believe water is densest at several degrees above freezing.
Correct - at about 5c/42f - except with high salt content.  With greater salinity, that oddity vanishes.

17
Arctic sea ice / Re: The 2019 melting season
« on: September 20, 2019, 08:59:36 AM »
It is interesting to note that there is a pattern to the very bad years of 2007, 2012, 2016, and 2019. <snip>
As far as I remember that's what "be cause" is posting in his signature on a daily base, at least interesting indeed
the art of the ( not so ) subliminal message ? . b.c.
I see more random behavior:
<snip>
2010 was a bad year. (and *really* bad for volume loss...)
<snip>
More important: On PIOMAS September volume, 2019 is going to be almost as bad as 2012.   
My interest now is going to be... will the overheated winter temperatures we saw in 2016-17, 2017-18 and to a lesser degree 2018-19 continue?

And then as a follow on... will 2020 be more of the same (more or less like the last 4 years), or a rebound like 2013?

18
Arctic sea ice / Re: The 2019 melting season
« on: September 12, 2019, 09:15:20 PM »
According to Jim's graphs, ice volume has decreased from 14.9 to 4.7 * 1000 cu. km from mid 80's to now
This represents approx 0.35 * 1000  cu km change / year  at time of minimum volume. Assuming a BOE occurs  when there is 15% of the 16,000,000 max in 1980 and an average thickness of remaining ice of 1 metre, the volume at a BOE would be 2.4 cu km
Therefore , at 0.35 * 1000 loss in vol / year , we could expect a BOE in (4.7-2.4)/0.35 = 6.6 years
This makes a big assumption - that system behavior will be consistent as we reach that limit.

Based on the surprising end of season slowdown this year, I'm not sure that's safe. I'm still mulling hypotheses for what we are seeing and why the dynamics are not falling more in line with your assumptions. 

"Blue Ocean" is a boundary condition, and the retreat of the ice to where it stands now - post 2007 - suggests to me that the dynamics for the ice north of 80 are significantly different from those of the peripheral seas, which is were most significant visible changes in the Arctic have unfolded.

The ice in the CAB and along the CAA by dint of higher latitude appears less influenced by the effects of insolation and atmospheric heat.  It is also *somewhat* protected by the deeper waters of the central basin.

I  think it will require more import of oceanic heat - from the Atlantic side in particular - to push the system out of the state I think it may have settled into.

I think we may see quite a number of years like this - following the pattern of post 2012 - with the ice retreating to the high-latitude bastion we see.

We *could* see a weather driven event driving a season below 2012, but am leaning more and more to a conclusion that this would be anomalous rather than a signal of impending BoE.

I think we need a lot more data on changes in Arctic ocean enthalpy changes, as I'm thinking that and attendant changes in water column structure are what will drive us to a BoE.

19
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: September 12, 2019, 08:49:08 PM »
Except that your graph shows anomalies throughout the year.  While volume has continued dropping at other times of the year, that cannot be said for the Sept. minima.  Check what others posters have presented regarding volume at minimum.

The whole point was that I think anomalies through the year is a better indicator than minima.
Based on my expectations of 2019 extrapolated from conditions, and the current surprising (higher than I expected) numbers, I'm thinking there may be sense to this hypothesis.

20
Arctic sea ice / Re: The 2019 melting season
« on: September 05, 2019, 06:53:41 PM »
Dorian's track:

https://www.nhc.noaa.gov/refresh/graphics_at5+shtml/151958.shtml?cone#contents

It will be interesting to see what effect of heat inputs from two hurricanes and (currently) two additional tropical disturbances will be in about a weeks time.

There may be no effect except to hinder freezing.  It is possible the heat may permit bottom melt to continue with a resulting late minimum.  I don't expect the numbers to be dramatic.  If melt does continue it will likely be at a trickle of 10-15K/day; at least that's my expectation.

21
Arctic sea ice / Re: The 2019 melting season
« on: September 05, 2019, 05:12:24 PM »
And the hole that's been appearing in the Lincoln Sea is as large as I've seen it.


I am no expert and I have only been following the Arctic for the last 7 or 8 years but I have never seen the Lincoln Sea in this poor of a condition.
+1
I agree - it's astonishing.

Here's how it *should* look.

22
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 27, 2019, 11:50:55 PM »
Considering momentum, heat in the water and everything else, the slowdown over the last week is nothing short of astonishing to me.

I really didn't expect to be wrong concluding extent this year would drop under 4 million KM2, but am happy that it appears it won't.

As I said elsewhere, seems there's a factor we are missing somehow.

I've been speculating for a while about that. Maybe, the ice is in such a bad condition that mostly volume is being lost at this point and the remaining ice continues to disperse, keeping up with the two-dimensional losses.  Of course, the only way we will know is to wait a couple weeks on  the PIOMAS numbers.
Contemplating volume as well.  I may try to hunt down some numbers and see if anything relevant jumps out at me.  If it does, I'll post over on the melt season thread.

23
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 27, 2019, 11:38:07 PM »
Considering momentum, heat in the water and everything else, the slowdown over the last week is nothing short of astonishing to me.

I really didn't expect to be wrong concluding extent this year would drop under 4 million KM2, but am happy that it appears it won't.

As I said elsewhere, seems there's a factor we are missing somehow.

24
Arctic sea ice / Re: The 2019 melting season
« on: August 19, 2019, 07:56:49 AM »
Anyway... Here's an updated version of the five day forecast. There's been an interesting development over the CAA, where that storm that smached itself to pieces on the Alaskan coast is reorganising itself on the other side over the CAA. 976 hPa is pretty low, and it seems to be strengthening. This could get interesting in the coming days!
976hPa is a serious storm, especially in contrast to the high pressure domes elsewhere over the region.

Depending on location and duration, this could stir up some heat from depth.

25
Arctic sea ice / Re: What's wrong with HYCOM?
« on: August 19, 2019, 02:59:38 AM »
Trump administration may have pulled the plug on it.

https://www.eenews.net/stories/1060877355

26
Arctic sea ice / Re: The 2019 melting season
« on: August 15, 2019, 09:23:13 AM »
Weather forecast for the next 4 days.
This is so cool... :D
Thanks PETM!
I ended it with the smiley face that's still in the forecast... ;)

It looks like the southern part of the CAA will melt out, and the state of the Eurasian side of the ice + forecast suggests significant losses on the way.

How much of the northern CAA will hold out?

Will this wind finally drive the ice off of the Atlantic Islands where they've held on stubbornly all season? And will that result in any retreat of the ice along the Atlantic side where positive concentration anomalies are high?

Will the Beaufort be able to swallow all of the ice being pushed into its waters?

Any crystal ball owners out there?
We are now past the peak of insolation, and the remaining ice is for the most part above latitudes that will receive significant insolation between now as the equinox.

Heat blowing in from the continents will have a minimal effect, as it isn't accompanied by significant insolation or long-wave radiation.

All hinges now on bottom melt, and to a certain degree, on how much heat is pulled from depth by wind.

I think a 2nd place finish is pretty close to being "in the bag".  I'm doubtful that we will pass 2012 - *UNLESS* the melt season continues into late September, driven by bottom melt.

Unfortunately, that store of heat - what's already in the water - is an aspect of the Arctic we probably have the least information on.  We can only wait and see what transpires.

27
Arctic sea ice / Re: The 2019 melting season
« on: August 12, 2019, 05:19:19 AM »
A new high pressure system could be entering the arctic in 5 days from now. 1040 hPa is quite high right?

https://earth.nullschool.net/#2019/08/16/1800Z/wind/surface/level/overlay=mean_sea_level_pressure/orthographic=-37.55,98.87,1500/loc=-172.775,66.338
High pressure in 5 days, if widespread, not so much a problem for the ice. Insolation is dropping like a stone.

However, 1040 PA combined with a low someplace else... potential trouble for the ice.  Especially as this high is over the Chukchi and with 40+pa gradient could shove ice out of the main basin into "superheated" waters of the Beaufort.

28
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 12, 2019, 05:05:40 AM »
I'd be extremely surprised if there was any refreeze this early. This requires sustained low temps, often initial refreeze occurs at -10C. I am quite certain this was an AMSR2 artifact.
I was talking about pond refreezing, not ocean refreezing.
That's how I interpreted you.

That would translate as area increases.

29
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 09:48:06 PM »
This ice has been hammered by high pressure for many weeks now, and it looks like it's in really bad shape. I don't see how all this can survive the high temperatures of the coming week. The surface temperature at this moment is 3.5°C.
The actual heat that can be transferred at this point I don't think overall will make that much of a difference.  Unless there's a lot of moisture in the advection, the heat content of the air is insufficient by itself to cause a lot of melt.

As insolation above 80 now is *also* starting to drop off rapidly that leaves just that heat already captured in the upper layers of ocean to do the work.

To that point, I think the danger to the pack right now is less the direct heat being delivered by advection, and more that it will interfere with the exchange balance, preventing loss to start from the ocean out of the atmosphere.

So, two $64 questions - how much heat has been captured, and how much of it will get pulled to the surface?

30
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 09:39:06 PM »
Interesting to see gaps in the ice showing up in worldview as far north as 89N. The attached link is to an area of cloud free ice from 150W to 150E (due north from Barrow to the ESS/Laptev border) and from about 88-89N (100-200km from the pole.)
It's in a terrible state all the way to the Pole. Yesterday's imagery shows it well, no fancy channel-fiddling needed!

https://worldview.earthdata.nasa.gov/?v=-306950.4643315668,-193208.65791401532,348409.5356684332,146247.34208598468&p=arctic&t=2019-08-10-T16%3A00%3A00Z&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines
Meanwhile, same date in 2013 we have this what's shown below.  I'm not sure the state of the ice at the pole will be indicative of outcome.

31
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 09:35:03 PM »
NSIDC for the 10 th puts sea ice extent at 5.093 M km^2 a drop of 166K km^2. 

Lowest on record!!!  2012 was lowest for just 2 days!.

2012 has lost its big chance to pull away and now its going to be a nail biting ride to the finish.

I don't understand. Looking at the Charctic chart 2012 hasn't been the lowest for some time.

Charctic uses 5-day averages. On daily values posted in the area and extent data thread it was lowest.

Mean while, pulling this thread over from there, considering JAXA:

NSIDC Total Area as at 9 August 2019 (5 day trailing average)  3,570,381 km2

This melt season is riveting. I think we have still not fully understood what a dramatically cloudier, wetter Arctic will behave like. Your observations about the current circulation and weather conditions is the right question to ask. I have none of the answers.

With all of the early open water and heat uptake, combined with the new cloudier Arctic holding that heat in, it would not surprise me if we have ridiculously warm autumn temps and a very slow refreeze.
With all due respect, there's nothing counter intuitive between the current weather and the extent drop.
FooW explained it very well a few days ago: warmth and compaction over Laptev and ESS, a cyclone messing up Beaufort, and continued heat in CAA
It's not the extent drop; it's the *lack* of extent and (particularly) area drop under what appear to be good melt conditions I'm wondering at.

32
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 11, 2019, 09:24:11 PM »
>>>> moved to melt season thread

33
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: August 11, 2019, 08:26:23 AM »
NSIDC Total Area as at 9 August 2019 (5 day trailing average)  3,570,381 km2

The 7 day turnaround has stopped.
On 8 August area loss collapsed.
On this day area loss collapsed even more.

Fascinating.  The collapse is running counter to everything we tend to expect from the current conditions. Consider for example the SST map from Climate Reanalyzer below. Consider also the current circulation and weather conditions.  What is happening is completely counter-intuitive.  It suggests we are missing some major factor.

34
Arctic sea ice / Re: "Stupid" Questions :o
« on: August 11, 2019, 08:14:53 AM »
The climate changed wildly throughout the Pleistocene and they did fine.

NOPE

El Cid:
There were about two dozen ice age cycles in the Pleistocene similar in speed and amplitude. When humans reached Australia there was an extinction event. When they reached the Western Hemisphere there was an extinction event. But in Africa where they had the most time to adapt to our hunting they did relatively well, and somewhat so in Eurasia.
There is still a lot of debate around the topic.  While H. Sapiens no doubt had an effect, they aren't the universal answer, and even in "new" territory like the Western Hemisphere and Australia, there are species for which that answer doesn't make sense.

It also doesn't make sense for many of the extinctions in Asia and Europe, where humanity and the megafauna *did* co-evolve.

Climate played a role as well.

35
Arctic sea ice / Re: Does El Niño affect Arctic sea ice?
« on: August 11, 2019, 07:55:27 AM »
I've done an extremely messy attempt to see if there was any correlation between Arctic temperatures and the ENSO index. Conclusion: The year following a positve ENSO sees a warmer arctic, the year following a negative ENSO sees a colder arctic. Mostly, but not all the time.

I used Zach Labes arctic temperature charts (https://sites.uci.edu/zlabe/arctic-temperatures/), and my own homebrewn ENSO charts based on https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php

The (very ugly) attempt is below, I've drawn blue lines from the negatives, and red lines from the positives in the ENSO graph down to the Arctic Temperature graph.

If anybody had links to monthly arctic temps then I might play around with making some prettier graphs. I might even go looking for monthly arctic temps tomorrow!
I see some literal gaps in your theory (e.g. around 2003-2008 or so stands out)  where there aren't any corresponding high points and low points.

I'm sure the ENSO contributes, but I think we're an awful long way from showing any kind of direct correlation.

36
Arctic sea ice / Re: The 2019 melting season
« on: August 04, 2019, 08:33:25 PM »
The battle for the North Pole?
The cyclone is there right now.
Will this cyclone push ice towards Nares?
It will cause the ice to disperse which should slow the drop in extent even more. At this stage of the season though, export of ice is not the key to the minimum. Melt in the CAB is and a more disperse ice may be more prone to melt.
Area loss should indeed rise, in the style of 2016.  We may again see end of season numbers with extent higher than 2012, but area under.

37
Arctic sea ice / Re: The 2019 melting season
« on: August 04, 2019, 08:44:28 AM »
The heat can mostly move through conduction
You mean convection I assume?
Nope. Conduction.  No convection through the halocline unless wave action stirs things up.

38
Arctic sea ice / Re: The 2019 melting season
« on: August 03, 2019, 10:08:52 PM »
The low over Bering is fortunately in favour of the arctic proper and it's to hope that it stays that way.
Unfortunately, both GFS and ECMWF show pretty strong ridging showing up over most of the pacific side about 120 hours out - which is within our "reliability" envelope.  As noted above, there's also potential for a  low to form over the CAB smack on top of the pole.  It will be concerning if that strengthens and we get *both* a dipole *and* a major storm.

39
Arctic sea ice / Re: Arctic Image of the Day
« on: August 01, 2019, 09:54:59 PM »
So glad the webcam is up and running again  :D
Very stormy, lots of rain, grass is growing really well!
Look at that surf!  Dang!

I'd be concerned if I lived in any of those near-shore houses.

40
Arctic sea ice / Re: meaningless freezingseason/melting season chatter.
« on: August 01, 2019, 07:19:58 AM »
sh wrote: "For me to believe year round BOE, someone would need to explain to me what conditions would prevent portions of the Arctic Ocean from freezing in the long, dark Arctic winter."

I can think of a few factors that could come into play, some of which we have already witnessed:
Well the sea around Svalbard (and even a couple of hundred km to the north at times) does not freeze in winter in spite of there being a long dark Arctic winter there. On the Atlantic front, we quite often see Ice-free conditions through winter in (admittedly) small areas north of 80 degrees.

So a warmer North-Atlantic current that stretches ever further north along the surface, particularly if coupled with clouds during winter, might well keep a very large part of the Arctic ocean ice free all year round.
Much depends on salinity and total system heat present.

Greenland still presents a serious "cold pole" as does Siberia/Yakutsk.  As long as we see snowfall over these regions, I think at the very least, near shore and the CAB north of the dropoff at Nansen basin will probably continue to freeze seasonally through the end of the century.

41
Arctic sea ice / Re: The caa-greenland mega crack
« on: August 01, 2019, 07:11:59 AM »
Aslan - on the topic of benches, the crack actually offers an explanation that doesn't require a full melt out of the basin.  Factor in post melt elastic rebound and you have a working theory for how they got there.
I'm a bit suspicious here - I don't think a crack of 10 to 20 km, even occurring every year, can explain beach formation. Waves inshore would be very small and insignificant, espcecally since the crack seems to form mainly when offshore winds are strong and persistent.

The beach ridges described in the literature above seem quite substantial, indicating a large wave fetch in onshore winds.
Agree 10-20 is not sufficient.  100-200 would be. 

Also consider, what are those benches cut in? Bedrock or sediment?  If sediment, it could have been frozen; we've seen how even modest surf has been chewing up permafrost along the Alaskan coast.

Like I said though, its the core of a hypothesis, which could be tested.

42
Arctic sea ice / Re: The caa-greenland mega crack
« on: August 01, 2019, 01:06:44 AM »
Aslan - on the topic of benches, the crack actually offers an explanation that doesn't require a full melt out of the basin.  Factor in post melt elastic rebound and you have a working theory for how they got there.

43
Arctic sea ice / Re: The 2019 melting season
« on: July 30, 2019, 07:47:29 AM »
Laptev/Kara covering the FJL gap to the Barents.
This is a larger area - about 4,000,000km2.
First image from the 16th, second the 29th of July 2019.

A lot of the ice in the lower left is above 80N, and will see rapidly decreasing insolation over the next 10 days.

Not as much will disappear from this region, but the portions to the top and upper right will likely be gone in 2-3 weeks.

72.53, 98.21 upper right
84.90, -135.53 lower left

44
Arctic sea ice / Re: The 2019 melting season
« on: July 30, 2019, 07:34:50 AM »
ESS - Different region, similar area, slightly longer time span - 7/12/2019 jumping to 7/29/2019. 
73.90, -160.05 upper right
73.42, -173.50 lower left

Again, virtually all of the ice in the later image should be gone in two weeks, as the region in question will still have fairly high levels of insolation and significant momentum.

Keep in mind, most of the lower image, as awful as the ice looks, is still 30% coverage in so far as extent is concerned.  Area shown here is about 500,000km2.

45
Arctic sea ice / Re: The 2019 melting season
« on: July 30, 2019, 07:23:17 AM »
What a difference 2 weeks makes.
Beaufort, 76.62, -165.12 upper right, 72.41, -140.43 lower left.  Somewhere between 600 & 700,000km2.

(Edit) Keep in mind this is "relatively" low latitude.  Insolation in two weeks will not be dropping like a rock here  the way it will north of 80.  Most of the ice in the 7/29 image, if not all, should be gone, unless it is replaced by export from the CAB or CAA.

46
Arctic sea ice / Re: 2019 vs 2012
« on: July 30, 2019, 06:51:16 AM »
For a sense of what may be to come...

Single image of the median of 3 days ending July 28, 2019

vs.

Gif of 5 day lagging median, July 28 - Sept 14, 2012 (click to animate, large file).
Viewed like this, 2012 doesn't look like it's that far ahead.
Well, it is actually behind 2019, so that may be why...
My point, obscured by my attempt at being droll.

47
Arctic sea ice / Re: 2019 vs 2012
« on: July 30, 2019, 06:46:18 AM »
For a sense of what may be to come...

Single image of the median of 3 days ending July 28, 2019

vs.

Gif of 5 day lagging median, July 28 - Sept 14, 2012 (click to animate, large file).
Viewed like this, 2012 doesn't look like it's that far ahead.

48
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: July 29, 2019, 07:12:40 PM »
Attached is a graph showing cumulative losses from August 1st to the minimum.

Despite starting with a lower extent each decade, the area lost is increasing each decade. 
    ....

This is quite significant. For volume, anomaly charts suggest the trend leans opposite. (I haven't scrutinized the data, which appear highly variable by year.) If so, the combination implies a shrinking but resistant end-of-season blob over time.
I think latitude counts for a lot as the pack has shrunk.  It is also pulled North which means that the angle of incidence changes more rapidly and dramatically during the melt.  In short, while peak insulation is high, the timeframe is short, and what can practically be captured is less.

Lower latitude ice has longer timeframes to capture heat, and that capture over time will be more consistent.

At high latitude my hunch is increases in loss will be driven more by net increases in system heat over time, primarily imported from elsewhere.

49
Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 08:15:09 AM »
Some kind of Transpolar movement is back upon us. If this remains sustained big trouble would follow, but hopefully the weather will change before the ice mass moves into the Atlantic killing zones.
Mostly it looks like it will pile up against N. Greenland, and possibly Svalbard/Fram.

50
Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 08:14:00 AM »
It seems to me incredible the way the whole Arctic sea ice has moved away from Canada & Greenland.
With the high temperatures that we are having there, should we expect some melting there? It is the place where we have the thickest ice.
I'd expect a slightly higher decrease in area, and moderate decrease in volume/thickness.  I'm not expecting this year will be able to apply enough heat to destroy it.

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