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bbr2314

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Re: The 2019 melting season
« Reply #4250 on: July 21, 2019, 10:05:37 PM »
It's that simple: place the question in Stupid Questions, and let bbr answer. I bet he's clueless as f**k
Yes, heat does not melt ice, that is definitely not a thing, especially not when insolation is still near peak and record ridging is projected to develop alongside massively warm 850 temps. Wow, I am clueless. I bet ice melts when it is -10F instead of during a scorching summertime setup that is essentially unprecedented!

It is going to get quite warm AND sunny over the CAB and Beaufort. This is pretty bad I guess. Attached ecmwf 12h run, T+6 (but looks like this from T+4 to T+10 basically), 850 hPa temp anomaly (yellow warm, blue cold)
But will the unprecedented combination warmth and sun melt the ice? How is that possible? I'm sorry, I don't understand, and I'm too dumb to go to the stupid questions thread to ask this. Sorry!

FishOutofWater

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Re: The 2019 melting season
« Reply #4251 on: July 21, 2019, 10:09:21 PM »
I suspect the worst pattern for ice at this time of year is the dipole pattern with low pressure in the ESS and high pressure over the CAA and Greenland. It favors the export of sea ice, the mixing of ocean heat with ice and intense melting of ice in the passages of the CAA.

petm

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Re: The 2019 melting season
« Reply #4252 on: July 21, 2019, 10:10:36 PM »
That's an awesome animation, awesome technique and I'd like to know if it is explained somewhere in the Forum... Thank you
Welcome. I like it too -- it helps to remove the distracting cloud artifacts and show persistent trends, which otherwise one has to do by "squinting". I do it using the imageJ API (Java code), basically by: for each day, reading in the 5 preceding days' images, converting each pixel color to a concentration value based on the Bremen key, taking the median for each pixel, then creating a new image. (Actually, the algorithm is easily changed -- 5 day median is quite conservative.) I can share more details and code if you like in a more appropriate thread.

Crocodile23

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Re: The 2019 melting season
« Reply #4253 on: July 21, 2019, 11:19:52 PM »
The world is on fire. 2012 vs. 2019. Oh well. The sheer number of fires this year is astounding. Click attached to animate.

Where is this?

Why would a huge high pressure ridge be bad for ice retention? Just because insolation is still high for a few more weeks? But wouldn't it also bring an end to the winds? Wouldn't big storms be worse?
Not to be a b*tch but there is a stupid questions thread for a reason.

https://forum.arctic-sea-ice.net/index.php/topic,143.0.html

Since we're always presented with insolation during high pressure as the main reason for that to be bad for the ice and since the sun-angle where there is still more or less solid ice is already quite flat/low, this was by no means a stupid question.

Some exaggerations here and doomsday-buzzword feeds and sensationalism here are way more stupid IMO.

Last but not least call someone who ASKS a question instead of babbling away stupid is
bad etiquette and the most stupid at the end of the day are those who don't ask.

Furthermore since isobars of the forecasted high system are predicted to be dense enough, it will be a lot windy. We should not forget that for equally spaced isobars anticyclones produce higher winds than cyclones (https://rgsweather.com/2015/02/09/high-pressure-windy-round-the-edges-a-bit-on-super-geostrophic-winds/).

ColdMiser123

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Re: The 2019 melting season
« Reply #4254 on: July 21, 2019, 11:40:41 PM »
Growing confidence for a impressive dipole pattern to take over beginning ~D3, and lasting for at least a week. EPS, GEFS, and their respective deterministic operational runs are extremely poor for ice retention, and we have a legitimate shot at keeping pace with 2012 over at least the next ten days.


uniquorn

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Re: The 2019 melting season
« Reply #4255 on: July 21, 2019, 11:43:57 PM »
I can share more details and code if you like in a more appropriate thread.
Yes please, in this one? https://forum.arctic-sea-ice.net/index.php/topic,1259.0.html

philopek

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Re: The 2019 melting season
« Reply #4256 on: July 21, 2019, 11:48:30 PM »

Furthermore since isobars of the forecasted high system are predicted to be dense enough, it will be a lot windy. We should not forget that for equally spaced isobars anticyclones produce higher winds than cyclones (https://rgsweather.com/2015/02/09/high-pressure-windy-round-the-edges-a-bit-on-super-geostrophic-winds/).

Good and important point, thank you for bringing it do everyone's attention again.

FWIW, i share the opinion of those who predict dire times for the ice, only that it is legit to have second thoughts and ask questions to optimize the base on which opinions are based.


Sterks

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Re: The 2019 melting season
« Reply #4257 on: July 21, 2019, 11:55:36 PM »
I can share more details and code if you like in a more appropriate thread.
Yes definitely, as long as you have the time, where Uniquorn indicates will do. Thank you!

be cause

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Re: The 2019 melting season
« Reply #4258 on: July 22, 2019, 12:10:50 AM »
  So what should we fear most .. a GAC or two , a dipole to die for , or this glorious High dominating the Arctic for a week circumnavigated by the weakest of lows ?
 
  Whatever the weather , this ice is in trouble , it has been since winter .

 wrote this some hours ago .. in light of discussions above .. I post .. b.c.


 

 
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

Shared Humanity

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Re: The 2019 melting season
« Reply #4259 on: July 22, 2019, 12:29:32 AM »
The best path forward is the current path. There is nothing you, me, or anyone else can do about it.

Certainly off topic but why is it that you come here?

UCMiami

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Re: The 2019 melting season
« Reply #4260 on: July 22, 2019, 12:31:40 AM »
While warm air is obviously a driver of melt, warm water is a much more effective driver. With lots of arctic ocean heat locked below the surface and not in contact with ice, the more and deeper the turbulence in the arctic ocean that more of that deeper heat is brought to the surface. At the same time the more the ice itself is moved about within the ocean, the more of its own self created insulating pocket of cooler fresh melt water is dissipated. The fact that these conditions are most associated with low pressure storms than with extensive high pressure systems leads people to conclude that strong low pressure systems especially at periods of high mobility within the arctic ice might be a stronger driver of low arctic minimums. 2012 with the GAC seemed to provide proof of this model.

A strong dipole may actually describe a best of both worlds provide both strong importation of warm temperatures while providing sufficient pressure gradients to create strong winds to move the ice and create ocean turbulence to bring deeper heat to the surface.

In some of the forecast models the size of the high pressure seems to fill the whole arctic basin - likely providing clear skies and isolation but perhaps not enough wind/turbulence?

I know that is a very basic and simplified description. But it seemed like it might be useful in the above discussion

bbr2314

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Re: The 2019 melting season
« Reply #4261 on: July 22, 2019, 12:33:25 AM »
The best path forward is the current path. There is nothing you, me, or anyone else can do about it.

Certainly off topic but why is it that you come here?
Why do you come here? I am here to watch the ice melt and to learn from others. It is not my fault if you believe in delusions that are disproven by the ongoing course of human history.

Instead of insulting me and dragging the thread off-topic again why don't you try answering the question of how removing aerosols won't result in a BOE and a crisis magnitudes worse than today's. Bueller? Bueller?

subgeometer

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Re: The 2019 melting season
« Reply #4262 on: July 22, 2019, 12:50:10 AM »
The world is on fire. 2012 vs. 2019. Oh well. The sheer number of fires this year is astounding. Click attached to animate.

Where is this?

western Siberia

Shared Humanity

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Re: The 2019 melting season
« Reply #4263 on: July 22, 2019, 12:52:12 AM »
Signal to noise ratio is deteriorating on this site. Will be signing off for a while.

be cause

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Re: The 2019 melting season
« Reply #4264 on: July 22, 2019, 12:52:42 AM »
It looks like the heat threatening to break records in France is then heading to the Arctic , delivery time @ a week by latest gfs forecast . Probably sooner .
 
 Why does bbr come here ? Share your Humanity and don't ask ! On the dullest day in winter he is as present as he is today .
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

sark

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Re: The 2019 melting season
« Reply #4265 on: July 22, 2019, 01:12:02 AM »
I do think the polar cell is failing outright.  Richard Alley said we'd have time to respond to it, that it wouldn't be SO ABRUPT that it would happen before we could do something about it.  Not 3 years, but more like 10 or 15...  well can we get started already

*third image requires click to run
I am not a scientist

subgeometer

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Re: The 2019 melting season
« Reply #4266 on: July 22, 2019, 01:12:53 AM »
It was meant as a genuine question. As far as I understand it, there is controversy about whether storms or sun are worse for the ice in the late season. There seems to be good reason to suspect that the 2012 GAC had a lot to do with that year's enhanced late-season melt. Well, I guess if we do end up with widespread high pressure instead of big storms this year, we can test that hypothesis (as Neven hopes), since so far this year's setup is arguably close to as bad if not worse than 2012.

But in any case, yes, I've moved it to Stupid Questions: https://forum.arctic-sea-ice.net/index.php/topic,143.msg214841.html#msg214841 .

Thanks.

WE're now 30 days past the solstice so the insolation v clouds equation must be similar to mid-late May, the main difference being the higher surface temps now which maybe favours clouds, since they insulate and hold that warmth in. OTOH a big high pressure ridge like this raises surface temps through the downwelling going on above it

bbr2314

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Re: The 2019 melting season
« Reply #4267 on: July 22, 2019, 01:23:48 AM »
I do think the polar cell is failing outright.  Richard Alley said we'd have time to respond to it, that it wouldn't be SO ABRUPT that it would happen before we could do something about it.  Not 3 years, but more like 10 or 15...  well can we get started already

*third image requires click to run
I strongly agree. I can't see another explanation for what is happening. I would imagine it will recover at some point this autumn / winter but what if it doesn't? In either case we are paving the path to a sustained record volume minimum heading into 2020 and possibly beyond.

sark

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Re: The 2019 melting season
« Reply #4268 on: July 22, 2019, 01:47:17 AM »
I am not a scientist

Rod

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Re: The 2019 melting season
« Reply #4269 on: July 22, 2019, 01:58:26 AM »
Chill out bbr!  You are taking advantage of the fact Neven is not here and being an ass.  I like your weather forecasts, and I think you often have valuable things to add to the discussion, but that does not give you a right to pretend you know everything and insult other members!

This melting season is an important one.  It has been since May.  Let’s see if the long range forecasts verify before we start talking doom and gloom. 

Personally, I have thought for a long time that if the ice in the Beaufort melts we will see a new record.  But, it still has not melted and we are long past peak insulation. 

If the predicted dipole actually happens, it will give us an opportunity to compare against the GAC of 2012. 

No one knows which is more important, because it has never happened in this way before. That is why we watch and compare and see what the outcome is.  Insulting people who have different views than you is not helpful, and it detracts from the good comments that you often make. 

sark

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Re: The 2019 melting season
« Reply #4270 on: July 22, 2019, 01:59:50 AM »
Focus
I am not a scientist

DrTskoul

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Re: The 2019 melting season
« Reply #4271 on: July 22, 2019, 02:03:55 AM »
A trove of data for the split arctic polar vortex can been found here : http://eh2r.blogspot.com/?m=1

There is a very strong feedback loop between thin ice and the shape of the polar vortex

Killian

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Re: The 2019 melting season
« Reply #4272 on: July 22, 2019, 02:21:52 AM »
There is no fix. Any fix removes aerosols and then we have a BOE and the world ends. The best path forward is the current path. There is nothing you, me, or anyone else can do about it.

Whether ignorance or suicidal ideation, this is B.S.

Does this software have a blocking function?

subgeometer

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Re: The 2019 melting season
« Reply #4273 on: July 22, 2019, 02:27:05 AM »
Ice north of the Laptev bite is poised ready to melt. Ice at 84N is almost as tenuous as the thinning ice not far from the  bite itself.

The cyclone that will stir the area over the next couple of days will advance things a way, then winds with the developing high pressure ridge/dipole will export some more of this  ice to its demise, either in the Kara, Barents or Laptev seas

I've included  an image of the area from 75-86N, 105-155E, as well as smaller areas from its south and north

petm

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Re: The 2019 melting season
« Reply #4274 on: July 22, 2019, 02:31:29 AM »
Let me echo, out of respect for Neven (and everyone): everyone please chill out. Moving discussion of sun vs. storms to another thread is fine and appropriate. Let's keep the heat focussed on the ice, so to speak.

Killian

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Re: The 2019 melting season
« Reply #4275 on: July 22, 2019, 02:33:59 AM »
This huge high pressure area that is forecasted, can only be compared to 2015 event...

One difference with the 2015 event was that that lasted 3 days while this from GFS forecasts seems to last 5-6 days(!).

Let's hope so, because it had zero effect on extent, which was pedestrian over the time of, and after, the high - via JAXA. Anyone care to check area?

petm

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Re: The 2019 melting season
« Reply #4276 on: July 22, 2019, 02:35:27 AM »
Does this software have a blocking function?

Yes, there's some kind of ignore file. I haven't used it personally, but I think you can find details on the Forum Decorum thread: https://forum.arctic-sea-ice.net/index.php/topic,1562.0.html

Killian

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Re: The 2019 melting season
« Reply #4277 on: July 22, 2019, 02:40:14 AM »
Why would a huge high pressure ridge be bad for ice retention? Just because insolation is still high for a few more weeks? But wouldn't it also bring an end to the winds? Wouldn't big storms be worse?

Makes sense it could, but in 2015 it didn't. So, the ever unpredictable ASI plays its little games with our littler minds...

However, if the potential high coming is a couple days longer, it might add to momentum by accelerating top melt, ponding, draining through the floes, heating the water between floes...

I didn't check the 2015 high's effect on area, though.

Killian

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Re: The 2019 melting season
« Reply #4278 on: July 22, 2019, 02:42:10 AM »
Let me echo, out of respect for Neven (and everyone): everyone please chill out. Moving discussion of sun vs. storms to another thread is fine and appropriate. Let's keep the heat focussed on the ice, so to speak.

?!

How are sun vs wind not part of the melt season?

DrTskoul

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Re: The 2019 melting season
« Reply #4279 on: July 22, 2019, 02:44:27 AM »
Like  a ball rolling down the hill, only a small nudge or downslope is needed
to keep the momentum going. If the ball is not moving the nudges going forward are not enough.  2015 did not have a great momentum.  2019 does.

petm

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Re: The 2019 melting season
« Reply #4280 on: July 22, 2019, 02:46:20 AM »
Let me rephrase: I am not offended by bbr suggesting that such a discussion be moved. Such suggestions are made all the time. Nevertheless I do think the discussion is relevant and directly related to what may be about to happen in the next few weeks. Now we have it on 2 threads lol.

I would just like to help calm down the tone.

Killian

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Re: The 2019 melting season
« Reply #4281 on: July 22, 2019, 02:52:49 AM »
The best path forward is the current path. There is nothing you, me, or anyone else can do about it.
Certainly off topic but why is it that you come here?
It is not my fault if you believe in delusions that are disproven by the ongoing course of human history.

Instead of insulting me and dragging the thread off-topic again why don't you try answering the question of how removing aerosols won't result in a BOE and a crisis magnitudes worse than today's.

1. You dragged it off-topic with your editoralizing.

2. Aerosols are an issue, but you are over-stating it by a good order of magnitude. Effect is smaller than originally thought and far less abrupt.

3. You weren't insulted. What reason do you have to pay attention if humanity is screwed? This suicide cult crap pisses me off. Think as you wish, but it is unethical and immoral to spread a suicidal opinion all over the internet encouraging hopelessness.

4. Your opinion is factually incorrect.

This will be my last on this. If you persist on spouting your suicidal ideations, I will track down that blocking function/app and block your posts and encourage all others to do the same.
« Last Edit: July 22, 2019, 02:58:39 AM by Killian »

HapHazard

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Re: The 2019 melting season
« Reply #4282 on: July 22, 2019, 03:03:13 AM »
Think I might just start posting pictures of trains in these Cryosphere threads. Or maybe start chatting about my horses. I mean, who cares, it's not like it would make the pointless noise levels in here any worse.

Someone wake me up when Neven's back.

subgeometer

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Re: The 2019 melting season
« Reply #4283 on: July 22, 2019, 03:05:53 AM »
I do think the polar cell is failing outright.  Richard Alley said we'd have time to respond to it, that it wouldn't be SO ABRUPT that it would happen before we could do something about it.  Not 3 years, but more like 10 or 15...  well can we get started already

*third image requires click to run

It seems to me like its bifurcating between states. For the past week say, it looked a bit more like itself again, with high temps and levels of moisture kept neatly  outside the Arctic basin. Now a big blast of precipitable moisture is about to punch right through its guts from the Pacific, as well as  substantial heat being sucked in from the continents.

Killian

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Re: The 2019 melting season
« Reply #4284 on: July 22, 2019, 03:08:46 AM »
Analysis: Looking at Windy, compaction should be the norm for the 21st everywhere but western Siberia, but there is room for expansion and the strongest winds are there. Looks like a somewhat balanced day of expansion and compacting with more area contracting, so a little more than average. Call it a 100k drop for JAXA and tie the current low, +/- 10k.
I'm not sure Windy is a good tool for looking at the winds - Nullschool has the vast advantage of showing the globe rather than that irritatingly stretched semi-Mercator projection that Windy uses.

Thanks. Will look around for it.

petm

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Re: The 2019 melting season
« Reply #4285 on: July 22, 2019, 03:09:55 AM »

Rod

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Re: The 2019 melting season
« Reply #4286 on: July 22, 2019, 03:14:50 AM »
Let me rephrase: I am not offended by bbr suggesting that such a discussion be moved. Such suggestions are made all the time. Nevertheless I do think the discussion is relevant and directly related to what may be about to happen in the next few weeks. Now we have it on 2 threads lol.

I would just like to help calm down the tone.

Your question is the key question right now for this melting season. As we move past the peak insolation, what is more important, sunshine or a GAC? 

Lots of people think the GAC was not the key driver of the record low extent in 2012. 

This year, with a dipole possibly setting up at the same time as the 2012 GAC, we can compare the results.  It is a big deal, and you were not wrong for voicing your speculation on which is more important. 

We are all just speculating, and we wait and see what happens. 

bbr2314

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Re: The 2019 melting season
« Reply #4287 on: July 22, 2019, 03:18:26 AM »
The best path forward is the current path. There is nothing you, me, or anyone else can do about it.
Certainly off topic but why is it that you come here?
It is not my fault if you believe in delusions that are disproven by the ongoing course of human history.

Instead of insulting me and dragging the thread off-topic again why don't you try answering the question of how removing aerosols won't result in a BOE and a crisis magnitudes worse than today's.

1. You dragged it off-topic with your editoralizing.

2. Aerosols are an issue, but you are over-stating it by a good order of magnitude. Effect is smaller than originally thought and far less abrupt.

3. You weren't insulted. What reason do you have to pay attention if humanity is screwed? This suicide cult crap pisses me off. Think as you wish, but it is unethical and immoral to spread a suicidal opinion all over the internet encouraging hopelessness.

4. Your opinion is factually incorrect.

This will be my last on this. If you persist on spouting your suicidal ideations, I will track down that blocking function/app and block your posts and encourage all others to do the same.

I think I overreacted but I also disagree strongly on aerosols and I think research also backs my viewpoint. I will not continue this tangent and I apologize for my previous brusqueness.  :)

sark

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Re: The 2019 melting season
« Reply #4288 on: July 22, 2019, 03:22:18 AM »
Look above the ice surface, where the enthalpy of fusion does not mask the atmospheric heat.  This is why high pressure over the Arctic is bad.  Because it comes from both Beringian and Scandinavian directions simulataneously, cuts off an anticyclone, which parks smack dab over the North Pole.

Handful of analog years or not, this is unprecedented across the board in severity and is beginning to act like a system in transition.
I am not a scientist

bbr2314

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Re: The 2019 melting season
« Reply #4289 on: July 22, 2019, 03:47:35 AM »
Look above the ice surface, where the enthalpy of fusion does not mask the atmospheric heat.  This is why high pressure over the Arctic is bad.  Because it comes from both Beringian and Scandinavian directions simulataneously, cuts off an anticyclone, which parks smack dab over the North Pole.

Handful of analog years or not, this is unprecedented across the board in severity and is beginning to act like a system in transition.
It looks like the breakdown will continue for a week or more. The extended range shows the engorged ridge over Scandinavia and another forming over Siberia and I anticipate both of these contribute further to the dome over the Arctic. If you are correct then it may be much more than a week or so if this atmospheric behavior -- it could last months, at varying degrees of terribleness, but all of it will be terrible.

sark

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Re: The 2019 melting season
« Reply #4290 on: July 22, 2019, 04:02:20 AM »
It happened already every 6-8 weeks since November 2018 and completely from space to ground since May Day.  Bipolar cell.  It splashes back together in the middle and then grows octopus arms before splitting in half entirely, every 6-8 weeks, for about the past 8 months.  I could probably pull together a dozen complete polar cell split gifs I've made in that time
I am not a scientist

FishOutofWater

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Re: The 2019 melting season
« Reply #4291 on: July 22, 2019, 04:26:39 AM »
The basic dynamics of the atmosphere have not changed but the Brewer Dobson circulation - the movement of air and energy from the troposphere to the stratosphere and back down - has intensified. Zach Labe is studying aspects of this problem and knows the physics far better than I do. I could be getting something wrong because this is far beyond my training in physics, but it appears to me that this year has had the most stratospheric subsidence heating the polar atmosphere of any year we have been observing it with scientific measurements.


bbr2314

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Re: The 2019 melting season
« Reply #4292 on: July 22, 2019, 04:27:24 AM »
It happened already every 6-8 weeks since November 2018 and completely from space to ground since May Day.  Bipolar cell.  It splashes back together in the middle and then grows octopus arms before splitting in half entirely, every 6-8 weeks, for about the past 8 months.  I could probably pull together a dozen complete polar cell split gifs I've made in that time
Again 100% correct. I guess this time the duration will be longer than previous ones. And the octopus arms even more prominent / dangerous as more PVA spirals out of the Arctic and into the mid-latitudes (maybe this explains Hurricane Sandy in 2012).

wdmn

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Re: The 2019 melting season
« Reply #4293 on: July 22, 2019, 05:26:16 AM »
Another big loss (>100k) incoming on JAXA.

There is a lot of ice that is primed to go (including quite a few km2 in hudson's bay), and with the return of the bad weather, my main focus remains on how long the Atlantic side will hold on. The ice around Svalbard has barely budged through the big losses in July.

sark

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Re: The 2019 melting season
« Reply #4294 on: July 22, 2019, 05:48:19 AM »
AO index reaches positive territory briefly before this event.  What will happen next is anyone's guess.  On June 6-7 this new incursion was not predicted and AO was predicted to go positive. I was not convinced this dynamic fault could subside:
 https://twitter.com/systemrename/status/1148366995080896513

Although the models are trending toward a positive AO in the long range, this new heat incursion is strong and is forecast to pierce the polar front entirely.  The last couple have been rebuffed, and this was clear by hour +180 on each of those.  We're within 140 hours on this one and models are locked in on a pretty energetic anticyclone fed in from both sides of the planet & centered on the north pole.

Usually long range models have a better handle on the macro scale weather patterns.  This is something else.

I am not a scientist

Alphabet Hotel

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Re: The 2019 melting season
« Reply #4295 on: July 22, 2019, 06:00:19 AM »

There is a lot of ice that is primed to go (including quite a few km2 in hudson's bay), and with the return of the bad weather, my main focus remains on how long the Atlantic side will hold on. The ice around Svalbard has barely budged through the big losses in July.

There was a pretty clear image of the ice north of Svalbard from Sentinel 2 today. It looks pretty good and shows little to no surface melt.

S.Pansa

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Re: The 2019 melting season
« Reply #4296 on: July 22, 2019, 06:15:20 AM »
First semi-clear view on the ice in the ESS in a good week or so. Snapshot 1 is from  July 11th, second from today; Wrangle Island on the left.
A picture says more than tousand words they say ... for better details the shortlink to EOSDIS:https://go.nasa.gov/2JJ2UXX.
« Last Edit: July 22, 2019, 07:12:11 AM by S.Pansa »

Coffee Drinker

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Re: The 2019 melting season
« Reply #4297 on: July 22, 2019, 06:18:52 AM »
May I ask whats so special and unusual about the temperature chart? For a layman this is not obvious straight away.

What I noticed was a forecast of 12 degrees C north of Ellesmere Island and a wide area out over the ice above 8 degrees.

Thank you. Maybe I don't get so hyped because I already see those temps as the new normal of the Arctic.

Killian

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Re: The 2019 melting season
« Reply #4298 on: July 22, 2019, 07:08:54 AM »
All data JAXA ASI Extent.

7/21/2011 fell to 6.88, a drop of 70k.
7/21/2019 needs a drop of 100k+ km sq for a record low for this date.

2019 falls 120k km sq to 6.86M km sq.

2019 sets a new record for the date (as predicted a couple days ago on the data thread.)

7/22/2011 stood at 6.81M km sq. on this date.
7/21/2019 stands at 6.86M km sq., needing a drop of > 50k km sq. to set a record for the date.

Edit (forgot the prediction): Call it another 100k+. Mmm... 105+/-10k.

Analysis: Despite the mixed signals from winds alone, the cyclone in the Beaufort and winds coming from the Pacific and Atlantic appear to have won the day as they are the areas I see compaction: Chukchi, west Beaufort, northern Kara and northern Barrents. ASMR supports all this showing deterioration on the Pacific side.

Given the momentum, another day of above-average losses seems likely. For the 22nd, strong-ish cyclonic winds towards the central CAB in the Laptev, the Beaufort cyclone and cancelling or lighter winds elsewhere indicate another above average drop in extent. Adding in ASMR from 7/21 reinforces this as do continued warm SSTs.

(I am beginning to hate clouds. I like to look at the ice myself to interpret all the data coming in. Grrr...)

Updated: 7/25/2012 fell to 6.62M km sq., overtaking 2011 and setting a record low for this date. 2019 needs an average daily drop of > 60k km sq. for a record low for this date. Conditions suggest this will happen. I'm not quite confident enough to call it certain, but > 90% chance, imo. Even if so, I'd expect 2012 to be lowest again sometime between 7/26 and 8/10 due to > 300k km sq drop at the end of July and the > 1M km sq drop from 8/2 ~ 8/10/12, but that specific prediction is very premature.
« Last Edit: July 22, 2019, 07:26:10 AM by Killian »

Wildcatter

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Re: The 2019 melting season
« Reply #4299 on: July 22, 2019, 07:54:55 AM »
Goodness. Those cyclonic winds have done some damage on the northern pack. Even the two day difference is striking. And there's more of the same today. Beaufort as well. Looks to be significant thick ice retreat.


Strong 10m winds coming right up the Bering. 20-30 knots.


If the projected forecast pans out, this could get ugly.