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Messages - aslan

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1
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 02, 2019, 08:00:40 PM »
Daily gain 170 k, 46 k MORE than the 2010's average of 124 k.

Still very high, and just three seas (ESS, Laptev & Kara) gained 164 k of that total.

_______________________________________________


I think this is an important point. The biggest difference with 2016 is the Kara Sea and to a lower extent the ESS. Kara Sea has seen quite unexpectedly high sea ice gain and is ahead of the most recent years (2016 and after I mean). Big gain in ESS and Laptev is a fatality, nothing can make for shallow waters and fresh water. But now that the sea ice has hit the hard land, ESS and Laptev can't see any more gain, this two seas are already near the 100% mark. If Kara sea is not able to sustain the surge in gain, it is likely that a stall in Arctic sea ice extent will happen. As for now, the great battle of this winter for Chuckchi and Barents sea is starting, and easy ice gain are likely over. I am quite ready to bet that Kara Sea will not be able to sustain the pace, and that we are going to see stall shocking the extent growth like in 2016. The biggest hope for now I think is the Beaufort Sea, the only sea which can keep things up for now I think.

2
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 19, 2019, 12:17:23 PM »
Even for the Arctic Ocean, we will be hard press to end the winter with at least a 2m first year ice, putting the risk of a memory of this summer. The islands on the russian side are nearing or breaking record which are only a few years old, like Ostrov Vrangel :

http://www.pogodaiklimat.ru/monitor.php?id=21982&month=10&year=2019

versus 2016 :

http://www.pogodaiklimat.ru/monitor.php?id=21982&month=10&year=2016

Or Ostrov Kotelnyj :

http://www.pogodaiklimat.ru/monitor.php?id=21432&month=10&year=2019

versus 2018

http://www.pogodaiklimat.ru/monitor.php?id=21432&month=10&year=2018

Or Ostrov Vize :

http://www.pogodaiklimat.ru/monitor.php?id=20069&month=10&year=2019

versus 2016 :

http://www.pogodaiklimat.ru/monitor.php?id=20069&month=10&year=2016

And again, a layer of low level clouds is keeping in check the refreze, as shown for example with Ostrov Vrangel between 300 and 600 meters since the end of the Summer :

http://ogimet.com/cgi-bin/gsynres?ind=21982&decoded=yes&ndays=50&ano=2019&mes=10&day=19&hora=06

And SSTs are still extrememly warm, locally up to 7 or 8 (!) °C. And with the clouds in place, cooling is going to be slow. It is a sure bet that southern Chukchi would not freeze before December or January, and it is increasingly likely that this sea could not fully refreeze before the end of the winter.
For now, the downward IR flux at surface is a bit less averaged over Arctic comapred to record holder 2018 and 2016, meaning a bit more heat is escaping the furnace of the Arctic. But we are starting with an ocean wich is way warmer than in 2016 or 2018 and to cool down this thing this small diff is not enough...

3
Consequences / Re: Forests: An Endangered Resource
« on: September 27, 2019, 05:48:20 PM »
Yes, it is already some years that horse chestnut is screaming its sorrow and pain. It is often question of Amazon or Indonesia or California... but here in northeastern France trees are dying everywhere, it is crazy. Bark beetle are eating away forest, and relentless heatwaves are drying trees. You can't walk 5 meters in any forest without spotting dead trees after dead trees, of any species, old one or young one. Leaves are already falling here, which is really early -and while temperatures are still high and there is no frost still-.

https://www.foretpriveefrancaise.com/data/fe248_p54_60_1.pdf

In the mean, around 10% to 20% trees are dying now. With an annual harvest of 12 millions m3 it is at least 2 millions m3 of damaged wood for this year for France. But locally up to 80% to 90% (!) of trees are dry and dead. Hornbeam, beech, spruce, ash, douglas, you name it.

http://www.fncofor.fr/docs/library/secheressequestions-reponsesonf-fncoforseptembre-2019.pdf

Here it is named a "sanitary crisis", but it is no longer a crisis as it is only worst years after years. It was already very, very bad in 2018, and "only" very bad years before. It is just that mass mortality is growing more massive years after years. And in Deutshland or in Switzerland it is no better.

4
Arctic sea ice / Re: The 2019 melting season
« on: September 06, 2019, 11:44:13 AM »
Sum of forces is definitively not the same. Ice and water does not respond in the same way to winds. And there is also hydrostatic equilibrium, 100 hPa is worth one meter of sea level, but zero point zero meter of ice level. And of course in the end gravity would even out the sea level if the winds stop blowing.

5
Arctic sea ice / Re: The caa-greenland mega crack
« on: September 03, 2019, 09:47:01 PM »
Yes thanks longwalks ;) If there is specfic interest for the Nare Strait, the work of A. Münchow is worth citing :

"The established flow of seawater from Pacific to Atlantic Oceans through the Arctic has been attributed to higher sea level in the Pacific (Wijffels et al. 1992), associated with the lower salinity of Pacific waters. Sea level in the Atlantic may be more than 0.5 m lower than in the Pacific and 0.1–0.3 m lower than in the Arctic (Muench 1971). More accurate estimates of steric forcing have yet to be determined, but it is probably safe to conclude that much of the drop in sea level between Arctic and Atlantic Ocean occurs along the 530-km length of Nares Strait, thereby providing the impetus for the fluxes that we have measured.'

https://journals.ametsoc.org/doi/full/10.1175/JPO2962.1

https://www.researchgate.net/publication/233704692_Ocean_current_observations_from_Nares_Strait_to_the_west_of_Greenland_Interannual_to_tidal_variability_and_forcing

6
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: September 03, 2019, 09:22:10 PM »
Ok, I might be stubborn,  ;D but I will rephrase more abruptly. What if the change in sea ice extent does not reflect a change from an energy point of view?

7
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: September 03, 2019, 04:22:09 PM »
Without wanting to look harsh, but I think the discussion is taking a bad way. I am not a specialist of this question, but a big missing piece of data is the problem of land versus ocean distribution in Northern Hemisphere.

I think it is useful to go in several different directions. Extract what we can from trends but also consider physical reasoning.

I am not sure I agree on the importance of land restricting ice extent. It certainly does in winter but it is constrained at same places each year. So I am not convinced it has much effect on trends.


If I may insist. Considering for example an uniform retreat of 1° northward per decade, Summer as Winter.
If the ice edge is 1 000 km long, the 1° will lead to 100 time 1 000 km², i.e. 100 000 km² ice loss over a decade. Or, said otherwise, peanuts.
If the ice edge is 10 000 km long, this will lead to 10 000 time 100 km², i.e. 1 000 000 km² ice loss over a decade.
This is really what is ongoing. In winter, the "free" ice edge is not really wide, so even if the ice is marching toward the North at the same speed as in Summer, ice loss will be small. And as said, in the Pacific we are now in the bottleneck of the strait, and in the Atlantic it is not really better. So even a retreat of 2 or 3° over a few years will lead to almost no sea ice extent loss in Winter, while in Summer a retreat of 2° or 3° will be almost the end of the sea ice. This is simple but important math’s. Of course, it makes the evaluation of trends in ice extent more complex. But I really do think brain storming over breaks of the linear slope without acknowledging this fact will lead to a sterile discussion. The changes in slope are way more better explained by changing ice edge conditions than by "hard" physics.

https://tamino.wordpress.com/2010/08/22/on-ice-with-a-twist/

8
Arctic sea ice / Re: The caa-greenland mega crack
« on: September 03, 2019, 03:05:44 PM »
Yes, the conditions are more suitable for ice export in Winter, mostly due to variation in sea surface elevation :

Our model results based on 26-years of simulation with monthly output demonstrate that SSH gradients (calculated between two points north and south of each passage, which are denoted with asterisks shown in Figure 12) do explain the annual peak volume fluxes (around March) through both Nares Strait (Figure 14a) and Lancaster Sound (Figure 14b). The volume flux anomalies and SSH gradient anomalies are also highly correlated. Volume flux anomalies through Nares Strait (Figure 15a) and anomalies of the SSH gradient (measured from the Lincoln Sea to Smith Sound) (Figure 15b) were highly correlated (R = 0.89). Volume flux anomalies through the mouth of Lancaster Sound (Figure 15c) and anomalies of the SSH gradient (measured between the Queen Elizabeth Islands and western Baffin Bay) (Figure 15d) were also highly correlated (correlation R = 0.85).

https://pdfs.semanticscholar.org/870a/ad3242a2f319c69031342c9cedfa291df51e.pdf

9
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: September 03, 2019, 02:40:21 PM »
Without wanting to look harsh, but I think the discussion is taking a bad way. I am not a specialist of this question, but a big missing piece of data is the problem of land versus ocean distribution in Northern Hemisphere. I mean, in winter, ice edge is constrained more by geography (coast of Russia and Canada) than by physics (warming / cooling atmosphere, ocean currents, and so on). Which is no longer the case in Summer, where ice edge is, but for Greenland, in open Ocean and can retreat as the thermodynamics warrants. This is probably why seasonal cycle changed dramatically after 2005. Until 2005, ice was still mostly bounded by the coast, even in Summer. Now, ice has all the possibility to expand and retreat without being imped by the coasts. One possibility is to look instead at sea ice edge latitude. Doing this, difference between Summer and Winter is lessened and the downward trend is more even.
On top of that, captain obvious helping, it should be noted that sea ice area can't go negative. But this has the implication also that the downward trend should go to zero sooner rather than later, as there is no more ice to melt in summer. Losing 2 million squared km when you have like 20 million at hand is almost nothing, losing 2 million squared km when you have like 1 million at hand is impossible... This is probably the first big answer to the question "why trend is so irregular and the seasonal cycle has gone mad ?".

It should be noted also that from this point of view, the situation is “worsening” on the Pacific side. When the edge was in the Bering Sea, there was still some width to “yielded” big loses. Now that the edge is in the bottleneck of the strait, even a retreat of 1° North –which is quite significant– would amount to almost zero ice area loss. Zero time a thousand km is still zero :p We will have to wait for ice edge in winter to reached Beaufort / Chukchi / ESS for seeing anew some significant ice loss for the Pacific side. Same on the Atlantic side, as Barents and Kara Sea are zeroing, going further North will become complicated in the short term. It will happened in the decades to come of course, but over the course of the coming years, variability of winter sea ice as seen from the metric of extent will probably still be dampened, even if the warming speed up bigly.

https://www.tandfonline.com/doi/full/10.3402/polar.v33.21249

P.S. And on top of that "simple" geographical explanation, geaography also lead to "energy yield" vastly different from Winter to Summer. Land and Ocean distribution are also responsible for bigly different thermal answer in Summer and in Winter under the same forcing. We will also probably have to wait that the Ocean becomes an "heat accumulator" in winter for seing warming speeding up in Arctic.

10
Arctic sea ice / Re: The caa-greenland mega crack
« on: September 03, 2019, 07:17:06 AM »
Yes, it was bad wording on my part, not reflecting what I was actually thinking. It was more like, there was a strong preconditioning earlier with the lack of blocking in Nares strait, and now winds have an easier job.

11
Arctic sea ice / Re: The caa-greenland mega crack
« on: September 03, 2019, 06:42:42 AM »
This topic has drowned into the abyss of this forum, but the mega crack is still here and alive. And there is still sign of melt going on. To justify, Kap Moris Jesup hit 10.3°C the last day of August, a record for this time of year. And to the the North of Ellesmere, the Nares strait export has lead to a big, big hole. Fortunately the season is ending.

12
An unspoken consequence, here in northeastern part of France, is the sanitary situation of forests. Some plants are dying like never. Spruce, european spruce, beech, ash, bilberry etc... Many plants and trees are dying. And some are still alive but are on the brink of disaster like apple trees or more generally fruits trees which are not enough vernalized in winter. In my valley, there are big brown patches everywhere, like pictures in this article : https://www.lemonde.fr/planete/article/2019/07/24/la-secheresse-et-la-canicule-deciment-les-forets-francaises_5492869_3244.html And in the forest, we can't walk an hundred meters without seeing a tract of land which is dead. In Swiss, there is even a declaration of emergency ... https://www.letemps.ch/suisse/jura-situation-catastrophe-forestiere Consequences will be long lasting but big : flooding of the wood market with lower quality tree, increase risk of accidents, increase risk of forest fire, loss of biodiversity etc... The financial burden for some villages could be unbearable in years to come, as many rural towns have big incomes from the trade of wood. I don't know what a valley here could look like without beech, spruce, apples and cherries...

13
The rest / Re: Are you hoping for a global civilisational collapse?
« on: August 27, 2019, 02:01:34 PM »
It is ongoing, but I am not hoping for it, just preparing and praying the Lord. And reading ancient books from the late Roman Empire. But I am not a big fan of the world "collapse". Collapse will not happens instantly nor globally, but is an already ongoing step downward trend with some periods of temporary improvements, being better or worst here and there, and it is not going to be a global catastrophe over a day or so. https://books.google.fr/books?id=M4H-02d9oE0C&redir_esc=y Humans are often fascinated by big catastrophes, but the collapse of a civilization never followed this path.

Quote
I had problems voting here because I think the concept of collapse as given here is a bit of a straw man. I don't think it likely that it will be Armageddon, with hardly any survivors... but I'm sure there will, at some point, be a major reduction in population, and a reversion to a largely agrarian society in places that aren't used to such lifestyles. Many indigenous cultures will carry on, under trying conditions. What I expect to be the main symptom of collapse is the loss of the framework that allows intensive industrial civilisation. First there will be food shortages, then public unrest and lawlessness, then a new equilibrum will emerge later. The skills and knowledge to survive as sustainable communities still exist, although yes, life would be less comfortable. And yes, I expect this to happen (at least in part) within a few decades.

I fully agree. I am trying to build a sustainable community in my neighborhood, reviving ancient practices from the past.

14
Arctic sea ice / Re: The 2019 melting season
« on: August 24, 2019, 02:53:12 PM »
Thanks, no worries  ;)

15
Arctic sea ice / Re: The 2019 melting season
« on: August 24, 2019, 01:18:49 PM »
But, Aslan, before you said the low goes poof, not the ice. ;)

I am not sure to understand ? For me there were always arguments for saying that models are under estimating this beast. Not yet a true GAC but still quite deep and durable with migthy impacts for an already weakened ice pack.

16
Arctic sea ice / Re: The 2019 melting season
« on: August 24, 2019, 09:27:12 AM »
Models are trending deeper and deeper. Below 970 hpa will as forecasted now make this complex looking like a GAC. Brace yourself for ice armagedon.....

17
Arctic sea ice / Re: The 2019 melting season
« on: August 22, 2019, 09:04:49 AM »
This is the same low, or the same complex if one prefers. And IFS has output only every 24h. I don't have the exact evolution of SLP at end but this model is forecasting SLP lower than 980 hPa over central Arctic (GFS is at 978 hPa at 75h, a forecast time not available over internet for IFS to my knowledge). And it is not only about the minimum SLP but also about gradient, with a strong ridge on the Atlantic side, and multiple low centres interacting together. And it is also about Beaufort, as it is likely that the vertical stability of the Ocean column is weaker than in 2012. By the way, GFS, after a good fight up to this morning, has surender, so again it is way more likely that the models are under estimating this thing. Attached is the forecast 980hPa cyclone in 2019, and the 2012 GAC at 980hPa. We are not yet to the point where we can compare this low to the 2012 GAC, but this is going to be really, really bad for Beaufort sea and more generally for Arctic. Hope the best, but be ready. At 72h-96h lead time there is still time for loosing hPa.

But you can't possibly compare this low to the one in 2012 though as its a totally different set up.

First things first, the low in 2012 originated from Siberia so on its Western flank, there was warm air heading northwards towards the pole, this low is coming from Alaska/CAA and on its Eastern flank is cold air heading southwards. The warm air mixing in the circulation probably what caused the rapid development in 2012. Also the low in 2012 crossed over thin ice just at the right time and area which split the ice pack and what resulted in the dramatic extent losses, this low is crossing a ice pack which is not as thin as that was and nor is this low is as deep so its affects on the ice in theory should be minimal. It will be interesting too see how the ice reacts on the CAA and Greenland coasts with such strong winds.

I suppose never rule anything out these days but in the past, this set up should mean a rapid slow down in ice extent and some freezing of any diffuse ice in the CAB.

There is also a warm belt from Siberia, from the ridge over the coast. This also explains why the low is not as strong as in 2012 or 2016 from the point of min SLP. But min SLP is not the whole story, two 980 hPa lows playing together is not necessarily better than a big one at 965 hPa. Here, there is really multiple thermal waves with different sets of warm / cold fronts, with multiple warm belt feeding into the lows.

P.S. I have tried hard without success, but I will still show a sounding from GFS over ESS for Friday. I am showing this sounding, because at the same time IFS is showing an even steeper profile, with some weak mid level instability between 850 and 500 hPa. Here, GFS is a bit marginal. But nonetheless this is showing that there is a true warm belt feeding into the low from the siberian side (by the way, and again, this is also why the forecasted low from IFS is still bigger and stronger than the low from GFS).

18
Arctic sea ice / Re: The 2019 melting season
« on: August 22, 2019, 08:55:24 AM »
Models are concerning. The american and the euro boy are showing the possibility of a new thermal wave building day 7 - day 10 for a third round. IFS has probably gone made with a 980 hPa low over Beaufort at D 7. But GFS has the same idea. Even though, overall, the cyclogenesis fail, this boy is still trying something with a new stream coming from the american continent again. Energy will perhaps not been exhausted after a two punches low. For the moment, the low is still forecasted to weaken and spin down, but who knows? This said, this does not preclude a new ridge coming from the Siberia.

19
Arctic sea ice / Re: The 2019 melting season
« on: August 21, 2019, 10:44:55 PM »
a forecast time not available over internet for IFS to my knowledge

ECMWF forecasts every 3 hours can be found here:
https://kachelmannwetter.com/de/modellkarten/euro/nordpol/luftdruck/20190825-1200z.html

Thanks, not aware of this site. Crazy that they even have it every hour. Like what everything is available over internet...

IFS has output only every 24h.
Nullschool every 3 hours...

I wish there would be a Euro Nullschool, because we're way better with our weather predictions in Europe than the Americans are...



Nothing like bashing Americannots on your century post!  ;D ;D ;D 8)

Yes good job ^^ joke aside, GFS has been really behind the curve lately.

20
Arctic sea ice / Re: The 2019 melting season
« on: August 21, 2019, 09:48:53 PM »
This is the same low, or the same complex if one prefers. And IFS has output only every 24h. I don't have the exact evolution of SLP at end but this model is forecasting SLP lower than 980 hPa over central Arctic (GFS is at 978 hPa at 75h, a forecast time not available over internet for IFS to my knowledge). And it is not only about the minimum SLP but also about gradient, with a strong ridge on the Atlantic side, and multiple low centres interacting together. And it is also about Beaufort, as it is likely that the vertical stability of the Ocean column is weaker than in 2012. By the way, GFS, after a good fight up to this morning, has surender, so again it is way more likely that the models are under estimating this thing. Attached is the forecast 980hPa cyclone in 2019, and the 2012 GAC at 980hPa. We are not yet to the point where we can compare this low to the 2012 GAC, but this is going to be really, really bad for Beaufort sea and more generally for Arctic. Hope the best, but be ready. At 72h-96h lead time there is still time for loosing hPa.

21
Arctic sea ice / Re: The 2019 melting season
« on: August 20, 2019, 09:02:24 PM »
If it was 500 or 1000 km toward Beaufort, it would be a party of ice destruction.
In that location it smells season brake of an already braking season.

Again, this is definitively not the opinion of the Euro guy. I am ready to bet that this boy will be closer to the reality than GFS. The IFS at 120h - 144h is extraordinarily bad and the IFS at 96-192h is "only" really, really bad. There is a lot of energy to dissipate and the GFS, sitting like a big fat guy in his chair and waiting God knows what's sighing "Energy, which energy?" is really not a credible option in my opinion. Also, IFS (00Z or 12Z of this day) is able to go to a warm seclusion. This point is also not in favor of GFS. From the season, we have learned that the Arctic is under steroids and a cold, dreary frontolysis is not looking likely. Perhaps I am badly mistaken and fooling myself, but for me this is not looking like anything serious.
The point is really not about the deepening low above the archipelago. Now, every one is ok for a deep low over this region. But after, some models like IFS are able to let the low spinning, with a new feeding of energy from Atlantic and Eurasia, while GFS is letting this thing dying.
Perhaps it is the hour where Denethor is whispering the antithesis of your one signature to the lasts floes of sea ice still standing : "Why do the fools fly? Better to die sooner than later. For die we must."

22
Arctic sea ice / Re: The 2019 melting season
« on: August 20, 2019, 08:42:59 AM »
Yes GAC power !!!!  ;D
As it is in the range 96h - 120h, it is almost lokked in. Not as big as in 2016 or 2012 but still significant, sub 980 hPa at least, sub 970 hPa possible. But the radius of gale force is limited and it will occur over the Canadian Archipelago also, so with less impact for sea ice (but lest keep an eye on what will happen in the Beaufort Sea -especially after 120h-). In the end, it is a compromise between IFS and GFS, big cyclone, but coming from Alaska and not from Atlantic.

P.S. : For the Beaufort, what I wanted to say actually is that with the euro guy the low is able to reorganize itself and build a new thermal wave, streaming warm air from Atlantic and then Eurasia, but for GFS this will not happen and the low will spin down quickly. Again, I am skeptical of the solution offered by GFS. It was already not able to anticipate the deepening of this low, and now it want us to believe that it will be short lived. Even though the Euro guy was not sure about the precursor (the one from the Atlantic, or the one from Alaska ?), since mid week the model is quite consistent showing that some big pressure drop is going to occur, not matter the exact details.

23
Arctic sea ice / Re: The 2019 melting season
« on: August 18, 2019, 01:24:17 AM »
As CSNavywx noted a while back, ridges tend to persist and the models often underestimate the persistence. We should not ignore the latest Euro model run. We'll know that the threat to the ice is over when temperatures drop and area losses stop. The recent slowdown in extent losses was associated with a rapid drop in area, an indication that the melt season has not yet stalled out. The DMI 80N graph shows the melt season has gone into extra time.

I don't think that this means this year will catch up with 2012, but there's still time for surprises.

Yes, GFS is probably lost in the wilderness again. I have put also Arpege, a french model which is not often look but is often good and is a close friend of IFS, despite being coded quite differently. At 96-120 h, the low over north Pole must be closely monitored. It is not deep, but again it is deepening against a strong ridge. And so, a sub 995 hPa low vs a top 1025 hPa high result in a strong low level jet over CAB. I don't have all the tools for an analysis, but it also likely that the high and the low are feeding each over. Stronger high with warmer air mass is probably enhancing the baroclinic zone trough stronger temp gradient and stronger wind speed, helping the low to deepen. No GAC again, but these recurrent, nasty low battling strong highs are not helping. A solution like GFS with a broad low sipping a cold drink and waiting I don't know what would be way better but it is not really the most likely outcome.

24
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: August 17, 2019, 08:34:25 PM »
Yes it is probably the explanation, despite Copernicus showing data available since 2006. And yes it is really frustrating to be blind while the Beaufort sea is beaten like never. The beaufort gyre is quite an important thing, but who know what is really happening ?

25
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: August 17, 2019, 04:53:35 PM »
I make a quick map to compare 2019 on the 26th of August (forecast from Mercator) to mean from 2016, 2017, 2018. I don't know why, I was not able to download data for prior years, I don't know why... Excepted for the Barents sea which is cooler than over the 3 previous years (also the case for SSTs with a true base period), everywhere the warmth is showing, and even in the central basin there is streams of abnormally warm temperature.

26
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: August 16, 2019, 04:54:21 PM »
And now ITP 110 has hoisted the white flag and surrender. No news since two weeks. Too bad, as Mercator is showing extreme warmth in Beaufort. It should have been interesting to see what really happens here. The build up of heat shown at 30m and 100m is like nothing ever seen. Will this have an influence on refreeze season ? And Mercator was shown to be warming not enough compared to ITP 100. Depite this, in part of the Beaufort Sea, the big mess is going on and on, with a loosening of the stratification and a build up of energy wich is beyond superlatives and the "spot the difference" game ... Where now the Pacific layer and the halocline ? Where is the freshening and the cooling ? I don't know where we are going at this pace, but here we go.

P.S. : There is no special reason for a comparison with 2016, it was only to give a point of reference for a year wich was in its own quite bad for Arctic.

27
Arctic sea ice / Re: The 2019 melting season
« on: August 14, 2019, 02:04:57 PM »
Wind is basically going bonkers at the moment.

45 knots off the NE coast of Greenland into Fram. 20 knots from the Kara straight into the CAB and noticably moving the ice edge.

Same in Beaufort with 20 - 30 kts of easterly winds now. Ship NWS003 measured 51 km/h but not sure of the configuration of the anemometer and ASCAT is quite explicit. Wind speed is not extremely high but occuring over a wide swath around the high. Also models have been a notch too low for wind speed. The vertical profile is of course helping, with the lack of strong near surface inversion, but it is still interesting to see models not fully bringing winds to surface.

28
Arctic sea ice / Re: The 2019 melting season
« on: August 12, 2019, 01:05:54 PM »
This said, even without GAC, weather is going to be very rough on the Pacific side. Low over Chukchi is not so hollow, but there is strong gradient, and mean winds more than 30 kts are going to occur. Sea is going to be not so friendly, with wave action. As others said, GAC 2012 pumped heat from deep ocean, but this year there is way enough heat at surface for melting sea ice edge with a good shaker mixing. Same can be said on the Atlantic side. The low over Kara is only going to a bit below 1000 hPa, but interacting with a 1030 high, this is going to be a wild ride for sea ice in coming days. Hopefully it will not last, but damages are likely in the next 2 - 3 days. It should be noted that some mid level instability is again modelized in the WAA coming from Siberia  :P

29
Arctic sea ice / Re: The 2019 melting season
« on: August 12, 2019, 10:01:36 AM »
I’m really surprised that the lightning strikes 300 miles from the North Pole yesterday did not cause more discussion on the forum. 

The scientists on climate Twitter could not find any instance of lightning so far north.

It was a strange, and in my opinion important, event.  The arctic is changing!

This is from work, so no one has seen the following pictures... The IFS 0.125° for the 11th at 00Z, wet bulb potential temperature at 850 hPa, vorticity at 850 hPa (above 16, step 4), SLP, thickness 500 (Z500-Z100). There is  a front with a ribbon of vorticity to the North, stretching from the low over Barents to the Chucki sea, with low and mid level clouds, as visible from sat pictures. But associated with the low over Laptev, to the west of the head of the low, there is a maximum of vorticity. Sounding show mid level instability from ~800 hPa to ~250hPa with ~100 to ~200 J/Kg. Marginal, be with good forcings enough for TS.
As Rod said, this is significant.
For one part, this is an illustration of the evolving Arctic. Again, CBs were probably not directly linked to the crazy warm SST, but it is definitively showing that Arctic is warming. The warm air advection was extreme, and was able to carry a potentialy instable airmass up to 85°N. Mid level CBs at the head of a thermal wave are not a thing of the Arctic, up to today...
For the other part, this also means that cyclogenesis is on the move on the Arctic. This low had some characteristics of a warm seclusion with a slight max of temperature, TA and wind around 850 hPa - 900 hPa. Cold, pure baroclinic process are loosing a bit of grip and now warm core process and moist instability is starting to play a role. For the second point, it was of course more evident with the low over Beaufort at the start of the month for example. Here a lone CB will not make any meaningfull difference of course. But next year it could be 10 CBs, then etc... And on the end it will change the cyclogenesis process. It could also be noted that Laptev sea being shallow, it could quickly warm without sea ice. With Siberia snow free earlier and earlier, this could mean a quick increases of moist instability with a warming Arctic.

30
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 07:44:19 PM »
As an illustration of the growing importance of the convection for Arctic : https://mobile.twitter.com/Climatologist49/status/1160400333601832960

And on this GFS was not too bad (I did not look at IFS). Not yet to the point where subtropical storms Can be, but we are on the good way  :D

https://twitter.com/NWSFairbanks/status/1160456516849172480

It was probably mid level thunderstorms, starting from around 750 hPa. Strong shear and vorticity at this level probably help the convection. Sat pictures is showing top CBs down to -50° to -60°, which means a slight overshot, up to 250 hPa. In this case, surface conditions (i.e. batshit crazy SSTs) were not a direct factor. CBs starts in the warm air advection associated with a low centered around 84°N 135°E. But the WAA was extreme, with temperature above 10°C at 850 hPa in the ribbon of max temperature. CBs were probably on the western flank of thiw WAA, and not directly linked to the front to the North, stretching from the low over Barents to the aforementioned low. It is also likely the most northern strike detected.

P.S. : WAA can also - in this case - be traced with smokes. Coming from Taymyr peninsula in the morning (UTC time) of the 10th, and advected towards Laptev Sea on the 11th. Between the two pictures, on the western flank of the advection, something happened...

31
Arctic sea ice / Re: The 2019 melting season
« on: August 11, 2019, 09:35:43 AM »
As an illustration of the growing importance of the convection for Arctic : https://mobile.twitter.com/Climatologist49/status/1160400333601832960

And on this GFS was not too bad (I did not look at IFS). Not yet to the point where subtropical storms Can be, but we are on the good way  :D

32
Arctic sea ice / Re: The 2019 melting season
« on: August 01, 2019, 10:41:09 PM »

It was not fully intended, but by the way and by way of illustration, GFS has come closer to others global models, and is showing more deepening forced by diabatic heating.

And the follow-up... Sorry, but I like to understand how models works and to cook them, and why they are always in epic fail but are still incredible useful. The low is now forecasted to go down to 988 hPa -the attached image is showing 989 hPa but this is not the absolute minimum-, and this will probably be the last say. Don't be shy if you are sure that the models are shy :p So real world consequences, with a sea like rarely seen in Arctic, up to 4 m and 10 s, with Barrow and Prudhoe Bay going to be battered : https://tidesandcurrents.noaa.gov/waterlevels.html?id=9497645&units=standard&bdate=20190801&edate=20190802&timezone=GMT&datum=MLLW&interval=6&action=

33
Arctic sea ice / Re: All Greenland Fjords could be Sea Ice Free in 2019.
« on: August 01, 2019, 03:50:16 PM »
And this also means less buttress for ice tongue, and more ocean action.

P.S. : Sorry... Don't believe the spell checker sometimes  :P

34
Arctic sea ice / Re: The caa-greenland mega crack
« on: August 01, 2019, 03:49:19 PM »
Sea state is the sum of wind waves and sweel. And swell from Atlantic can be quite long even in summer. If swell from Atlantic can reach Greenland coast -and this is almost the case now-, you don't need a great fetch.

35
Arctic sea ice / Re: meaningless freezingseason/melting season chatter.
« on: August 01, 2019, 03:44:40 PM »
During the Eocene, CO2 was probably around 1000 pm and orbital factor were probably not a good explanation for equable climate. Despite this, Arctic was perennially ice free with subtropical fauna / flora up to Ellesmere -and the paleolatitude of the island was about the same that today-. But even more, during middle Miocene sea ice was probably restricted to central Arctic during winter (cf. https://www.nature.com/articles/ncomms11148 ) while CO2 was around 500 ppm. There is also some other indirect elements, like the fossils of a cool temperature forest on Bank island : http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.522.4554&rep=rep1&type=pdf -and usually cool temperate forest is not found with sea ice https://en.wikipedia.org/wiki/Temperate_coniferous_forest#/media/File:Biome_map_05.svg -.
Excepted for central basin (i.e. extent at 5 millions in winter), perennially open Arctic is not likely by 2050 but still possible. If we follow the same trajectory for CO2 emissions, the earliest decade this could really happen is 2070s or 2080s. Open Arctic in winter can probably be sustained with greater CO2, moisture, enhanced cloud cover and ocean heat transport I think. For ocean heat transport, I am strongly convinced by the theory of Kerry Emmanuel, saying that more hurricanes, and more poleward hurricane, could increase the ocean heat transport. The problem is that models needs large scale gradient for heat transport, but paleoclimatology show that it was definitively not the case. As hurricanes are mesoscale system, are not well handled by models, and don't need gradient for mixing heat, they check all the boxes for explaining why models and paleoclimalogy are on an head on collision trajectory.

P.S. : petm was speaking of year-round Arctic ice free but in my head in 50 years we will be in 2050. Excepted, this is no longer the case since 20 years now XD

36
Arctic sea ice / Re: The 2019 melting season
« on: August 01, 2019, 10:17:31 AM »
The only thing I see from the EC is a high pressure system over the Asian/Pacific side with compacting winds on Laptev and ESS to Chukchi-CAB, not really strong but sustained from D+3 to D+7. It could negatively affect the ESS remains.
Anything beyond is very uncertain lately.

GFS is in agreement with IFS for a deep low around the 10th, despite usual shifts from one run to the other, shift in strenght, localization, etc... The canadian guy is also not that far away from this solution. And there is strong arguments for a deep low. I think it is time to pay attention to a possible big low.

37
Arctic sea ice / Re: The caa-greenland mega crack
« on: August 01, 2019, 09:29:15 AM »
Yeah, I am not sure if I was clear in my last message but a crack of 10 - 20 km would not be enough for a beach. Of course we are probably not yet to the same situation than during Holocene. But it is starting to become really significant. Locally ocean is open over 50 km, excepted for small floes here and there. And, despite the title, it is probably not a "pure" crack. I mean, it is wind driven, but there is definitively some melt ongoing.  For example fjord Frederik Hyde is fully open since the 29th, with some melting, and now around the coast and Kap Ole Chiewitz, Kap Bridgemann, Kap etc... ocean is fully open over 30 - 40 km at least, save for small floes here and there. And around Kap Prins Knud etc... ( https://books.google.fr/books?id=uXwXL966F1cC&pg=PA261&lpg=PA261&dq=prinsesse+ingeborg+halve&source=bl&ots=JqhIF-Fsf5&sig=ACfU3U30-2i_yFBKmiH-tZT2ME0rwwm5VA&hl=fr&sa=X&ved=2ahUKEwjQseTql-HjAhV95eAKHXK1CQYQ6AEwDHoECAgQAQ#v=onepage&q=prinsesse%20ingeborg%20halve&f=false ) and somewhere in this corner of Greenland, ocean is even more open and exposed to Atlantic. And if there is still a ribbon of floes to the east, south of 80°N the Greenland sea is not really closed. And we have still at least one month to go before the end of melt season. This is not looking yet like Holocene, but there is definitively some tentative ongoing. And it is not looking like we will need a BOE for beach ridging over this caps.

38
Arctic sea ice / Re: The caa-greenland mega crack
« on: July 31, 2019, 01:20:12 PM »
It was already note in the melt season topic, but the paleoclimatology yield some interesting results regarding Greenland beaches :

https://s3.amazonaws.com/academia.edu.documents/39706551/A_10000-Year_Record_of_Arctic_Ocean_Sea-20151105-20427-ypl12t.pdf?response-content-disposition=inline%3B%20filename%3DA_10_000-Year_Record_of_Arctic_Ocean_Sea.pdf&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWOWYYGZ2Y53UL3A%2F20190731%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20190731T103208Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=432ae45252627a5e521862c4450140b2ac01590c2e9659657457cc992e700760

I know it is sometimes difficult to be a weather man, but some definitive sentences are not going to pass the test of time : "and the ocean bordering North Greenland is expected to be the very last area to become ice-free in summer (2–4). "
Well, it is not looking quite likely now...

Beches are also found on the northwestern coast of Greenland, along the Smith Sound -wich is clear of ice now also- : http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.474.336&rep=rep1&type=pdf

Differents results are found elsewhere also : https://courses.seas.harvard.edu/climate/pdf/DeVernaletal2005PA001157.pdf

Ossifrage had some good insights about this subject, saying that the last bit of sea ice would probably be found more to the west, near the northern border of Canadian Archipelago. This can also have consequences for glaciers which are still buttstressed by sea ice : https://www.cambridge.org/core/services/aop-cambridge-core/content/view/5E27A9E9493AC5A9FEE361A4248AF8FF/S0260305500264549a.pdf/div-class-title-sea-ice-and-the-stability-of-north-and-northeast-greenland-floating-glaciers-div.pdf
The pack being fully detached from land is also bringing new questions. If the ice is more mobile, this can have effect on wind stress, currents, sea ice movements, etc. Can it also means that the pack can break in multiple parts ?

39
Arctic sea ice / Re: Slater's thread
« on: July 31, 2019, 12:52:09 PM »
I stand corrected!

I've just been promoted by DrTskoul.

Translation from Google....

Γεροντοκράτορας                           Elder Emperor

Where's me crown?

Off topic, but it is as old as the human societies זִקְנֵי הָעָמ or זִקְנֵ֥י יִשְׂרָאֵ֖ל

40
Arctic sea ice / Re: The 2019 melting season
« on: July 31, 2019, 12:18:10 PM »
It was not fully intended, but by the way and by way of illustration, GFS has come closer to others global models, and is showing more deepening forced by diabatic heating.

Fascinating. So we should keep our eyes peeled for underestimated lows?

If only it was that simple :D But yes, it can be one of the conclusion.

41
Arctic sea ice / Re: The 2019 melting season
« on: July 30, 2019, 08:29:31 PM »
Could any climate model aficionados comment on whether (no pun intended) the model runs are responding to the rapid increases in open ocean (and should we expect them to)? Or if they are not responding, is there a noticeable systematic divergence between forecasts and observed weather?

Not sure if this is a practical question, but the circumstances seem to warrant it...

Edit: E.g. The attached forecast seems to respond, with the little remaining jet following the *current edge of the Pacific ice (*which will likely have moved considerably by the time of the forecast arrives in over a week).

Outside the question of the jet, there is also others consequences. Models are showing more influence of diabatic process and warm core process in cyclogenesis for example. The european guy (I don't bother wit GFS) this morning is forecasting TCU/CB in Beaufort around 72H with the weak low, and some warm core process definitively going on.

It was not fully intended, but by the way and by way of illustration, GFS has come closer to others global models, and is showing more deepening forced by diabatic heating. But it is still shy. IFS this evening is down to 993 hPa for this low, with stronger convection, and an another global model is down to 992 hPa. This has also consequences for sea state, as the aforementioned other global model is showing a sea of 4 meters and 10 seconds -again, probably a pleasant day for an Irish sailor, but for Arctic this is significant- while the sea state for 12Z IFS is not yet available. In the same time GFS is not able to build up a strong sea, as weaker low and weaker convection inhibit surface wind. But this is not specific to Arctic here, GFS is generally not the best global model. It is just a good illustration of the effect of changing surface flux. And of course, this would not have been possible 10 years ago with sea ice as thick as a glacier in Beaufort - surface flux being not significantly different from zero...- when sea was closed up to near the coast.

P.S. : Be patient just a few minutes :p Sea state of 3m and 7s at max for IFS, but still more than the sea state of GFS with less than 2m and 6s max period...

42
Arctic sea ice / Re: The 2019 melting season
« on: July 30, 2019, 08:23:44 AM »
Could any climate model aficionados comment on whether (no pun intended) the model runs are responding to the rapid increases in open ocean (and should we expect them to)? Or if they are not responding, is there a noticeable systematic divergence between forecasts and observed weather?

Not sure if this is a practical question, but the circumstances seem to warrant it...

Edit: E.g. The attached forecast seems to respond, with the little remaining jet following the *current edge of the Pacific ice (*which will likely have moved considerably by the time of the forecast arrives in over a week).

Outside the question of the jet, there is also others consequences. Models are showing more influence of diabatic process and warm core process in cyclogenesis for example. The european guy (I don't bother wit GFS) this morning is forecasting TCU/CB in Beaufort around 72H with the weak low, and some warm core process definitively going on.

43
Arctic sea ice / Re: The 2019 melting season
« on: July 28, 2019, 11:24:57 PM »
No idea what one calls this pattern but 250 hPa on nullschool is pretty impressive! (or a mess if you are looking for a nice rational jet stream!!)
https://earth.nullschool.net/#current/wind/isobaric/250hPa/orthographic=-64.39,88.54,568

Does anyone have a picture of what it should look like, just for those of us who don't exactly know. I'm assuming much more tight and circular?

Usually yes, but seeing polar jet making wild loops is not unusual per se in the NH this said. So I am not sure that the mean will help you, but it's the attached map. I think it is worth emphazing that it is normal for the jet to undulate. And the tropical heating has a huge influence on the jet.  And it was worst at some point in the precedent years. This said this year the jet is definitively weird again this year, Arctic is not helping, and tropics are marching northward.

44
Arctic sea ice / Re: The 2019 melting season
« on: July 28, 2019, 05:41:40 PM »
Just a word about the left and right arrow keys in Worldview, which have greatly enhanced my Arctic experience: they take you back or forward a day. The first time you load a day, the screen turns black for a moment. After that you can zoom in anywhere and animate with the arrow keys! The visual temporal data is richer for my understanding than anything else I see. It's all on the move up there.

One more thing: Worldview apparently rewrites its own URL in the address bar. That means you can just forward the URL and the recipient will see the same thing you had on screen. Most awesome! Here, for instance, you can see > 1 km2 gaps in the CAB at 82.5N:

https://worldview.earthdata.nasa.gov/?p=arctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor,MODIS_Terra_CorrectedReflectance_TrueColor,Graticule,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2019-07-28-T00%3A00%3A00Z&z=3&v=-613836.8177134156,580491.625339504,-449996.8177134156,666891.625339504&ab=off&as=2019-06-15T00%3A00%3A00Z&ae=2019-06-20T00%3A00%3A00Z&av=3&al=true

Ice is badly damaged in the sector, with significant gaps up to 83°N and ice loosing cohesion up 85°N. This is also reflected in the ice concentration map of yesterday. Too bad we don't have good data for sea state in Arctic. There is a wave train propagating toward this arm of ice, but we don't have more information. This is even showing at Prudhoe Bay, with an ongoing surge. https://tidesandcurrents.noaa.gov/waterlevels.html?id=9497645 Nothing remarkable, excepted that the wave train is not going toward the coast... Ice drift is quite impressive also, movement in one day seems to reach more than 30 km for some features.... We will see what happen in the next days, but significant melt is likely to continue on this side of the Arctic.

45
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: July 25, 2019, 03:21:33 PM »
In this particular case, what are we looking for in a temperature vs salinity chart? I ask because it may be a more efficient way of diplaying the profiles.

Salinity is usually used as a marker for layers of water. Usually, S between 31 and 33 is thought to be the Pacific Warm Water https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2014JC010273 but a freshening of warm waters is ongoing and should increase instability of the water column, as S is around 28 near surface, with the risk that this warmth make surface by mixing. At greater depth, the max at around S=35 is Atlantic water. In Summer, water are fresher (sea ice melt, water runoff) and warmer, with a positive trend due to warming (water source from Chukchi sea is fresher and fresher, warmer and warmer). This is showing in the Beaufort Gyre, with a higher max in temperature at lower salinity for the Pacific Water Layer. There was even some ITP profiles with a Tmax with salinity near 30, and a Tmin with salinity near 28... of course freshening of Pacific Water must reach a limit, and in the same time, as said by Bruce Steele, the warming of Chukchi Sea will shut down the donwelling. I am not sure where we are going, but here we go. And the Ocean is definitively heavily disturbed, there is way too much heat which was accumulated this season, and it is not over.



Inspired by your salinity movies, uniquorn, the illustration below is a suggestion for displaying the actual physical data they are based upon.

It would give a 'traffic light' of salinity at e.g. 0m, 30m, and 100m at the location of each recording device on that date - whether from a tethered buoy, drifting buoy or a ship.


My main immediate motivation in suggesting this is that it would allow a movie that extends back before the June 2017 start of the mercator display movie that uniquorn posted here on the 2019 melting season thread. That would give us a longer term view of how the salinity has changed.

I realize that it would probably be a lot of work to make this, but I think to could be a useful visualization tool. The picture is just an illustrative cartoon - I'm hoping someone will be kind enough and interested enough to produce such a display, or similar, using the actual data. (It's beyond my own personal skills at the moment, unfortunately.)

This said also, Mercator is not seeing the warming and freshening of Pacific Water... The profile is for the model where the ITP buoy made the 601th profile, on the 19th July of this year (cf. above). Quite a difference. And the same on the 19th still, over northern Chukchi sea. For making a movie, I think I don't have the time, nor the motivation, nor the bandwith :s

46
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: July 24, 2019, 09:57:50 PM »
Probably not yet, but we are nearing this point. The ITP110 buoy, on the 19th -the last complete profile....- was showing strong heat storage at depth, and a thickening of the halocline. Graph can be compared with Fig. 1 here : https://advances.sciencemag.org/content/4/8/eaat6773 and Fig. 2 and Fig. 5 here : https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2014JC010273

But there is also a freshening of the halocline, in connection with its thickening and shoaling (cf second paper). All in all, heat is still building up in the Beaufort but instability of the thing is also probably increasing, while the Chuckchi sea is effectively trying hard to reach breakdown but is not yet fully at this point.

47
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 06:39:06 AM »
Is there any prospect of extending the model back in time to before June 2017?
(I've always been very interested in the longer term trend in salinity.)
I have looked but mercator data pre june2017 is, I think, in different format, netcdf?, larger file sizes and only 0m, ie out of my download volume and probaby low results for effort. I would love to see it though if anyone has the skills and the internet connection.

Data can be download from Copernicus, available from 1992 to near real time. If you have specifics questions you can ask. But yeah, it is ncdf and it is big files, epic download and epic data manipulation. For example, surface SST for a 6 month period, northward of 60°N, is about 500 Mo XD

http://marine.copernicus.eu/services-portfolio/access-to-products/?option=com_csw&view=details&product_id=GLOBAL_ANALYSIS_FORECAST_PHY_001_024

48
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 10:45:16 PM »
Hi aslan .. the accumulated solar anomaly north of 70'  is interesting but 2019 needs an update .. is it keeping up with 2012 .. or fading with 2016 ?   We need to know ! :)  b.c.

Probably keeping up, but this are MERRA2 data, which update monthly only, around the 20th. The definitive answer for July is going to be in one month so... But Reanalysis from the NCAR, a bit less good for radiation flux,  but still good enough, and in near real time, is in fact showing that 2019 is still pumping a lot of solar energy in July. Spatial pattern is also important. Maximum anomalies in 2012 were over Atlantic and Greenland front and over land due to record low snow, while in 2019 it is really the Arctic Ocean which is exploding.

49
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 10:26:15 PM »
"This said, May 2019 was not so good for building up melting momentum, a point already underlined, and accumulated heat is still trailing a bit behind good years like 2012 from this point of view, as shown in the graph."

Aslan, apart from calling 2012 a "good year", how would you explain the +4 degrees anomaly on 925 Mb over almost all of the central Arctic. That anomaly accumulated all through may, june and july...
This May was the record warmest. Anything stated otherwise is a falsehood, and Aslan's statement is objectively wrong.


The graph is about the solar energy, not air temperature....

"This said, May 2019 was not so good for building up melting momentum, a point already underlined, and accumulated heat is still trailing a bit behind good years like 2012 from this point of view, as shown in the graph."

Aslan, apart from calling 2012 a "good year", how would you explain the +4 degrees anomaly on 925 Mb over almost all of the central Arctic. That anomaly accumulated all through may, june and july...
.

The graph is about the solar energy, not air temperature....

P.S. And yeah, of course, the phrase "good year" was a bit ironic, and yeah being above the 2010-2018 is of course already something. But again this is NOT about air temperature....

50
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 09:47:27 PM »
For the forecast, we can underline the 2 - 3 meters sea with a period of 8 - 10 seconds. Nothing extraordinary (an Irish sailor would probably call it a pleasant day XD) but for the Arctic this is quite a lot of energy for the sea state. I don't have a lot of memory for this kind of stats, but I think the last time the sea was so powerful in Arctic was during late August 2016.
The wind is funneled along the Alaskan coast and has the potential to bring mighty waves even though there is only a shallow low with min pressure hovering around 1000 hPa.
https://www.tropicaltidbits.com/analysis/models/gfs/2019072312/gfs_mslp_wind_ak_13.png
This is not going to help the halocline, by the way. Perhaps ITP110 will whisper something to ours ears in the coming days.



Wait ... this would imply (via the correlation) that sea ice is responding to insolation levels ... what about CO2...?   I would be interesting to see a multivariate regression including both.  Asking for a friend lol.

Of course longwave radiations are increasing at surface, but the effect for sea ice in June is not as important as the increased solar radiation. I did not do a multiple regression, this was not pertinent. The correlation and the variance explained are too low for trying to play with stats. I built the correlation with the net downward longwave radiation, which is negative (the surface gets longwave flux from the atmosphere but in the same time cools to space emitting longwave. The net result is negative). The flux at surface is of course increasing (surface can not radiate heat as effectively now as CO2 increases), but this does not explain a lot of things in Arctic in June. I could have built the correlation with downward flux alone, to eliminate the effect of higher temperature radiating more energy in longwave, but it would have not changed much.

https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2014JD022013
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016JD025819

This said, May 2019 was not so good for building up melting momentum, a point already underlined, and accumulated heat is still trailing a bit behind good years like 2012 from this point of view, as shown in the graph. But July is trying hard to push 2019 ahead.

[...]

Yeah I think I agree.

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