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sark

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Re: The 2019 melting season
« Reply #4550 on: July 25, 2019, 07:43:20 AM »
https://www.arcus.org/sipn/sea-ice-outlook/2019/july

"The projected median Arctic September extent from all contributions is 4.28 million square kilometers, with a quartile range of 4.0 to 4.6 million square kilometers. This is a slight drop from the June median Outlook of 4.4 million square kilometers"
I am not a scientist

F.Tnioli

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Re: The 2019 melting season
« Reply #4551 on: July 25, 2019, 07:51:54 AM »
...
I'm skeptical that any of them are important ...
I just sent you a PM with a link which should easily remove this scepticism of yours, as well as with further info on your other points. Like i said before, i believe it's best we move this dig into further physical principles and basics away from this topic.
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

Sterks

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Re: The 2019 melting season
« Reply #4552 on: July 25, 2019, 08:47:32 AM »
Under the current forecasts the ESS remaining ice will be cut from the pack and lay over near the coast for the rest of the melting season or until it melts out.

Aluminium

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Re: The 2019 melting season
« Reply #4553 on: July 25, 2019, 08:49:48 AM »
July 20-24.

2018.

Phil42

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Re: The 2019 melting season
« Reply #4554 on: July 25, 2019, 08:56:55 AM »
Similar to the North Greenland coast, some big chunks of fast ice broke loose off the Northern coast of Ellesmere island. I assume this is quite thick MYI that was there for a while. To me, this looks like another indication of the 'last refuge for the ice' deteriorating.

Sterks

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Re: The 2019 melting season
« Reply #4555 on: July 25, 2019, 09:02:32 AM »
July 20-24.

2018.
Thanks again Aluminium. Any chance you can increase the height of the cropping so that we can watch the potential collapse of CAA ice in your updates?

RoxTheGeologist

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Re: The 2019 melting season
« Reply #4556 on: July 25, 2019, 09:08:13 AM »
...
Completely different issue than SST. I saw that Rox referred to SST and thought she made a mistake which I did not correct.
...

Completely OT, but I'm surprisingly happy you determined my gender. It's almost as accurate as your analysis. Perhaps Rox = Rocks?

jdallen

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Re: The 2019 melting season
« Reply #4557 on: July 25, 2019, 09:47:25 AM »
i'd say we can safely settle on very approximate range of ~180...300 W/m2 absorbed at the surface under clear skies (high pressure systems) for late July / early August

So about 5-9 cm of ice per day might be melting under the clear skies of the big high pressure system soon to arrive in the CAB.


Reason: it takes about 35 W/m^2 to melt each centimeter of ice per day:
<snippage>
Doesn't that seem a bit high?
<snippage>

No, it doesn't for reasons having to do with the imperfect absorption of heat by the ice, as well as transfers of heat to both water and atmosphere.  This whole energy transfer thing is quite messy :) 

The heat generated by insolation if perfectly transferred to the ice would actually melt quite a bit more I think.
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Aluminium

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Re: The 2019 melting season
« Reply #4558 on: July 25, 2019, 09:50:17 AM »
Thanks again Aluminium. Any chance you can increase the height of the cropping so that we can watch the potential collapse of CAA ice in your updates?
I like this size and long sequences of similar data or images. Maybe I'll try to make something another when i have finished trip.

I shifted window by 30 px.

BenB

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Re: The 2019 melting season
« Reply #4559 on: July 25, 2019, 10:03:18 AM »
It has been commented, quite rightly, that the ice in Beaufort keeps being replenished with fresh ice, and is therefore melting out more slowly than it would otherwise do. In spite of that, the edge of the ice has retreated significantly over the past two weeks:


oren

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Re: The 2019 melting season
« Reply #4560 on: July 25, 2019, 10:09:33 AM »
Thanks again Aluminium. Any chance you can increase the height of the cropping so that we can watch the potential collapse of CAA ice in your updates?
I like this size and long sequences of similar data or images. Maybe I'll try to make something another when i have finished trip.

I shifted window by 30 px.
Thank you so much Aluminium, for these repeated and very useful animations. I know I am speaking on behalf of many. And thank you even more for shifting the window, this is a big improvement for CAA enthusiasts.

deconstruct

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Re: The 2019 melting season
« Reply #4561 on: July 25, 2019, 10:19:10 AM »
Others have mentioned it today, so I figured I would take a look at it myself - just north of Greenland four massive icebergs (not really sure what to call them since they are/were part of the "central" pack
I guess you could call it an ice shelf? Or as others call it here; "Fast Ice"?

[..] I measured the big piece (3) at 100 km long. That's immense! I guess it stays in tact as a large piece because it's very old, and therefore very strong ice?
It is certainly not an ice berg and not an ice shelf. An ice berg is ice calved by a glacier or broken of from an ice shelf, where as an ice-shelf just is a floating glacier/ice sheet.

This piece is, despite it's size, just normal sea ice, as you can easily see, by just going back one year, because on August 24th 2018* it wasn't there. So either it is just one-year ice or maybe 2-3 year old ice that was pushed there by currents/wind.

And I don't know how thick it is, but it is very probable at max 5-6 meters thick (and I would guess much thinner than that) and if flushed out to Fram it will break up into many pieces in no time.


* Compare on Worldview:
https://worldview.earthdata.nasa.gov/?ca=true&cm=swipe&cv=42&p=arctic&l=MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&l1=MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2018-08-24-T00%3A00%3A00Z&z=2&t1=2019-07-24-T00%3A00%3A00Z&v=167872.41952361912,-1049390.810252163,1150912.419523619,-533294.8102521631

deconstruct

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Re: The 2019 melting season
« Reply #4562 on: July 25, 2019, 10:35:27 AM »
I have to agree with rich. Temperature anomalies (2m) are at best marginally positive (1979-2000 base). There were years where the whole arctic basin was dark red on those anomaly maps.
I strongly doubt, that you will find years, where the 2m temperature anomaly in the CAB will be all "dark red", which in the climatereanalyzer.org maps would be around 8-10°C over normal.

The temperature over the ice pack (that is not directly adjacent to any coast where air warmed over land could be blown there) is nearly all the time just barely above 0°C.

You can look at any year you want at the DMI Graphs (http://ocean.dmi.dk/arctic/meant80n.uk.php) for Mean Temperature above 80°N (where the core ice pack sits). This temperature is shown daily, and it nearly never exceeds 2°C and never goes 1°C over the average during summer. 2016 does not look any different in summer than 2019 or any other year.
This is simply because all heat is going into melting ice (which happens every year), so the air cannot go a lot above 0°C, otherwise it would be cooled instantly by the ice below (and the ice therefore warmed).

As someone else already said:
Neither SST nor 2m Temp over the central ice pack can go a substantial amount over 0°C as long as there is ice. This would only be possible if all the ice has melted and the energy can go into warming the air and water abover 0°C instead of melting ice.

Therefore it is totally meaningless to look at 2m temp-anomalies over the CAB and conclude from a minor positive anomaly that there is no massive heat influx into the CAB. Even a +1°C anomaly can mean a lot of heat/insolation.


binntho

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Re: The 2019 melting season
« Reply #4563 on: July 25, 2019, 10:40:02 AM »
I have to agree with rich. Temperature anomalies (2m) are at best marginally positive (1979-2000 base). There were years where the whole arctic basin was dark red on those anomaly maps.
I strongly doubt, that you will find years, where the 2m temperature anomaly in the CAB will be all "dark red", which in the climatereanalyzer.org maps would be around 8-10°C over normal.
<snip>
Well you do of course get them during winter - massively red. But once temps go above freezing, getting a slightly pink hue is the best you can hope for.
because a thing is eloquently expressed it should not be taken to be as necessarily true
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Coffee Drinker

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Re: The 2019 melting season
« Reply #4564 on: July 25, 2019, 11:36:51 AM »
@deconstrut and binntho

Thank you, I do agree with what you say. Maybe I had those dark red colour in my memory from spring or autumn, not the middle of summer. The explanation, that the middle of the pack can't go much over 0C makes sense. Adjacent coastal areas, however, do get much warmer than they are now.

Rich

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Re: The 2019 melting season
« Reply #4565 on: July 25, 2019, 01:30:19 PM »

Therefore it is totally meaningless to look at 2m temp-anomalies over the CAB and conclude from a minor positive anomaly that there is no massive heat influx into the CAB. Even a +1°C anomaly can mean a lot of heat/insolation.

So what evidence would you look for to prove that a massive heat influx is actually taking place?

The simple answer seems to be that we should see a rapid increase in area loss, reflecting the onset of surface melt.

grixm

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Re: The 2019 melting season
« Reply #4566 on: July 25, 2019, 01:36:39 PM »

Therefore it is totally meaningless to look at 2m temp-anomalies over the CAB and conclude from a minor positive anomaly that there is no massive heat influx into the CAB. Even a +1°C anomaly can mean a lot of heat/insolation.

So what evidence would you look for to prove that a massive heat influx is actually taking place?


850 / 925 hPa temperatures.

deconstruct

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Re: The 2019 melting season
« Reply #4567 on: July 25, 2019, 03:02:39 PM »
So what evidence would you look for to prove that a massive heat influx is actually taking place?
Well, if you have winds coming from areas with temperatures much above freezing, than this heat must go somewhere, when it is tranported to the CAB. Wind speed, direction and the areas where it comes from can be seen in model outputs like at nullschool, where you clearly can see that higher temperatures are correlated a lot with wind speed, direction and source area.

You can also look at winds not only at the ground, but also in different heights in the atmosphere, e.g. at 1000 hPa and 850 hPa, where there is often a much bigger transport of warm air, which is at some point mixed into air at lower elevation. And if that warm air cools over the CAB, that heat must have gone somewhere.

https://earth.nullschool.net/#current/wind/isobaric/850hPa/overlay=temp/orthographic=-20.72,79.27,688/loc=-171.793,71.638


And if you have clear skies with a lot of insolation, then obviously also a lot of heat is transfered through radiation and that heat must also go somewhere.

If that much heat wouldn't go into melting the ice, we would see temperatures probably over 20°C in summer heat waves on the pole. And this is not unrealisitic, when you look at Alert on Ellesmere Island, which sits at 82°N, and it reached 21°C this year, despite that a good amount of Ellesmere Island is covered with snow and glaciers and surrounded by sea ice. The few ice-free land up there was enough, to warm the air to such a high temperature. You can see that in model output e.g. at earth.nullschool.com

So that there is a lot of heat influx, is IMO very clear in a certain situation. What is much more difficult would be, to quantify that, to get a grip on how much Joule of energy went into melting ice and how much ice would that melt and how much will be absorbed by the ocean (which partly will also go into bottom-melting later). But this is very likely stuff, that models like PIOMAS will do. Because they must calculate, how much ice melted where, and how else would they do that, if not by calculating the amount of energy that possibly went into melting the ice.

Rich

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Re: The 2019 melting season
« Reply #4568 on: July 25, 2019, 03:41:32 PM »

Thank you so much Aluminium, for these repeated and very useful animations. I know I am speaking on behalf of many. And thank you even more for shifting the window, this is a big improvement for CAA enthusiasts.

+1

FrostKing70

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Re: The 2019 melting season
« Reply #4569 on: July 25, 2019, 03:50:44 PM »

F.Tnioli

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Re: The 2019 melting season
« Reply #4570 on: July 25, 2019, 04:30:37 PM »
...
So what evidence would you look for to prove that a massive heat influx is actually taking place?

The simple answer seems to be that we should see a rapid increase in area loss, reflecting the onset of surface melt.
For area to start dropping, there must be openings larger than grid size for any given method of observation - open water areas or areas with significantly below-100% ice concentration which are dozens or hundreds square kilometers which are counted as "not sea ice", if we talk satellite sensors. Often strong melt happens without such openings forming, which is why massive melt may be taking place even while an area is "officially" remaining 100% area. Much depends on data parsing methods used by each particular research body, which actually differ quite much, too.

High air pressure areas is a major hint, traditionally used by many as a good indication during a melt season. Cloud cover direct observation (by satellites) showing areas without any cloud cover to talk about for significant lengths of time - is proof enough (as long as Sun pushes out high insolation during the season). That's if we just talk sunlight, of course. Bottom melt, rain, air heat waves, GAC-like events all have their own kinds of heat influxes and their own ways to be detected (which are not always possible to do).
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

Sarat

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Re: The 2019 melting season
« Reply #4571 on: July 25, 2019, 04:38:16 PM »
First time this month we have 2012 ASI Image for the date. Here is 2007/2012/2016/2019 comparison. I shifted the day since 12 and 16 are leap years.

« Last Edit: July 25, 2019, 05:46:47 PM by Sarat »

Milwen

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Re: The 2019 melting season
« Reply #4572 on: July 25, 2019, 04:42:08 PM »
HYCOM - Arctic ice thickness (CICE) model - July 25 - August 1

RIP Ice :'(




Sterks

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Re: The 2019 melting season
« Reply #4573 on: July 25, 2019, 05:12:10 PM »
HYCOM - Arctic ice thickness (CICE) model - July 25 - August 1

RIP Ice :'(

<Here outrageously wrong chart of thickness from the NAVY>

Meh
« Last Edit: July 25, 2019, 05:37:18 PM by Sterks »

Pragma

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Re: The 2019 melting season
« Reply #4574 on: July 25, 2019, 05:21:23 PM »
On the matter of how impactful this incursion will be, I think simple, just look to the heat this wave brings to France tomorrow.  42C / 107.6F with their own model. 

https://twitter.com/khaustein/status/1154144648199364608

I'm more interested in the potential temperature at 1000mb.  But with records falling every day everywhere around the world, you guessed right.


This is making fools of us.

I haven't got a clue as to what it is you are trying to say.

Anyone speak gibberish?
It isn't gibberish, you are the stupid one. The heat over France is bound for the Arctic by way of the record setting block now forming over Scandinavia. Models show it lifting into the ATL front and Greenland and merging with the existing Arctic block which is now getting underway.

"you guessed right" - Who guessed right and about what?

How is this weather event making fools of us?

If this post is referring to previous posts, it is customary to include quoted text so a reader can have some context and not have to go on a hunt through the thread.

And just to be very clear, I haven't insulted anyone. I highlighted a post that made very little sense to me, and still doesn't.

F.Tnioli

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Re: The 2019 melting season
« Reply #4575 on: July 25, 2019, 05:44:41 PM »
HYCOM - Arctic ice thickness (CICE) model - July 25 - August 1

RIP Ice :'(


RIP it is. If this is any correct, i'd say we'll have multi-hundred drops early august in the bottom-left quarter alone. So much white there, and i've seen, just couple hours ago, some forecasts of much clear sky in that same quadrant for next 3 days.
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

Killian

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Re: The 2019 melting season
« Reply #4576 on: July 25, 2019, 06:14:10 PM »
And just to be very clear, I haven't insulted anyone. I highlighted a post that made very little sense to me, and still doesn't.

Calling someone else's words "gibberish" is very insulting, speaking as an English language instructor. Directing it to third persons instead of asking for clarification from the writer reinforces the insult. More customary would be something like, "I'm sorry, I really can't understand what you are trying to say. Can you clarify?"

IMO, you were insulting, knew you were, and are now attempting to justify it.

At least, that's how the language reads.

Honestly, I don't care; this merely piqued my professional interest as a language issue. Do with the feedback what you will.
« Last Edit: July 26, 2019, 01:33:07 AM by Killian »

bbr2314

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Re: The 2019 melting season
« Reply #4577 on: July 25, 2019, 06:21:27 PM »
On the matter of how impactful this incursion will be, I think simple, just look to the heat this wave brings to France tomorrow.  42C / 107.6F with their own model. 

https://twitter.com/khaustein/status/1154144648199364608

I'm more interested in the potential temperature at 1000mb.  But with records falling every day everywhere around the world, you guessed right.


This is making fools of us.

I haven't got a clue as to what it is you are trying to say.

Anyone speak gibberish?
It isn't gibberish, you are the stupid one. The heat over France is bound for the Arctic by way of the record setting block now forming over Scandinavia. Models show it lifting into the ATL front and Greenland and merging with the existing Arctic block which is now getting underway.

"you guessed right" - Who guessed right and about what?

How is this weather event making fools of us?

If this post is referring to previous posts, it is customary to include quoted text so a reader can have some context and not have to go on a hunt through the thread.

And just to be very clear, I haven't insulted anyone. I highlighted a post that made very little sense to me, and still doesn't.
I haven't got a clue as to what it is you are trying to say.

Anyone speak gibberish?

TeaPotty

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Re: The 2019 melting season
« Reply #4578 on: July 25, 2019, 06:27:43 PM »
Got another good image of the sea ice destruction at 85N-60W area below, made a gif out of it.
From sheet to rubble in short time, in an area we used to think was safe, just north of Greenland.



Freegrass

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Re: The 2019 melting season
« Reply #4579 on: July 25, 2019, 06:29:05 PM »

It is certainly not an ice berg and not an ice shelf. An ice berg is ice calved by a glacier or broken of from an ice shelf, where as an ice-shelf just is a floating glacier/ice sheet.

Thank you for that explanation Deconstruct. I looked it up, and you're right, this can't be an ice shelf. I thought it could be because I presumed that there was a glacier present in that area of Greenland. But I guess there isn't any? And your image clearly shows that it already broke off last year, so it must be sea ice. What do you do call a big piece of ice like this? An ice float? I could use some of that ice here in Belgium now. We're hitting records of 40°C today.

Since this is already a little OT, I have a stupid question. What keeps the ice in the center of the arctic? I presume that this is because of the rotation of the earth? Or does the mass and gravity from Greenland have an effect on the ice? I remember reading or watching somewhere that as Greenland loses mass, the sea level actually drops, because the pull of gravity goes down with the mass of the ice. So I wonder what the effect of that mechanism has on the ice in the Arctic. Will the ice float away from Greenland one day? Or does Greenland make sure it'll always have the last sea ice in the Arctic?
« Last Edit: July 25, 2019, 07:16:46 PM by Freegrass »
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Freegrass

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Re: The 2019 melting season
« Reply #4580 on: July 25, 2019, 06:45:54 PM »
Got another good image of the sea ice destruction at 85N-60W area below, made a gif out of it.
From sheet to rubble in short time, in an area we used to think was safe, just north of Greenland.
And strong warm winds are predicted over the NAC in 2 days from now, with probably clear skies? The whole thing is gonna start spinning...
If every 8 year old in the world is taught meditation, we will eliminate violence from the world within one generation.

Rich

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Re: The 2019 melting season
« Reply #4581 on: July 25, 2019, 06:48:43 PM »
What keeps the ice in the center of the arctic?

Low temperature. No sun / solar radiation in winter.

Far from land based heat in summer. The perimeter sea ice offers a buffer.

Sarat

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Re: The 2019 melting season
« Reply #4582 on: July 25, 2019, 07:01:55 PM »
And strong warm winds are predicted over the NAC in 2 days from now, with probably clear skies? The whole thing is gonna start spinning...

And according to 1 week GFS forecast a cyclone will come in and reverse the motion. The great arctic washing machine.

Are slower drops in extent expected with this GAA? Looks like a lot of decompression going on.
« Last Edit: July 25, 2019, 07:24:38 PM by Sarat »

VeliAlbertKallio

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Re: The 2019 melting season
« Reply #4583 on: July 25, 2019, 07:24:43 PM »
As the spatial extent of the Central Arctic / North Pole floating sea ice cap reduces, the open ocean area correspondingly increases. This leads to increasing possibility of lopsided residual cap  that could drift away from its 90 degree north location. The residual cap can also eventually split and splinter into large separated units just before disappearing completely, which I presented at RSE VII, "Arctic - Mirror of Life", conference Ilulissat, Greenland in September 2007.
http://rsesymposia.org/hbmore.php?catid=164&pcatid=162&thehbid=27

University College of London's late Seymour Laxton's last suggestion was that there would be no sea ice left at the end of summer 2020, or slightly earlier. It looks like his view may hit the bull's eye. Sadly, he passed away a few years ago due to accidental fall on new year.

Frozen Isthmuses' Protection Campaign of the Arctic and North Atlantic Oceans (FIPC) proposed in 2005 complete melting around early to mid 2010's, Professor of Ocean Physics Peter Wadhams 2009 forecast was sea ice to disappear completely by 2012. On the early days there were less information on sea ice thickness which made it hard to make firm conclusions. Wiesław Masłowski is a research professor at the Naval Postgraduate School in Monterey who also made suggestions of sea ice being lost this decade much in line with myself and Peter Wadhams about decade ago.

Veli Albert Kallio, FRGS
Environmental Affairs Department
Sea Research Society
https://en.wikipedia.org/wiki/Sea_Research_Society

What keeps the ice in the center of the arctic?

Low temperature. No sun / solar radiation in winter.

Far from land based heat in summer. The perimeter sea ice offers a buffer.
« Last Edit: July 25, 2019, 07:30:17 PM by VeliAlbertKallio »
"Setting off atomic bombs is considered socially pungent as the years are made of fleeting ice that are painted by the piling up of the rays of the sun."

UCMiami

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Re: The 2019 melting season
« Reply #4584 on: July 25, 2019, 07:50:39 PM »
Using sea temperatures from Windy.com it still surprises me how long ice rubble is able to survive - in general the Hudson Bay water is 4-5C and yet the remnants of ice seem to remain almost unchanged for weeks in the SW of the bay. In the Kara temperatures are even warmer reaching 8C in places, though the remnants of ice on the easter shore of Novaya Zemlya are still hanging on.

I guess it shows how ocean waters do not mix as easily as one assumes unless the weather or strong currents give them a serious stir. And also how inefficient 'isolation' truly is in melting surface ice.

DrTskoul

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Re: The 2019 melting season
« Reply #4585 on: July 25, 2019, 07:55:53 PM »
If ocean is not mixing,  melting ice creates a cold fresh water layer around the floes creating and "insulating layer" slowing melting down to only the solar radiative input.

abraca

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Re: The 2019 melting season
« Reply #4586 on: July 25, 2019, 08:09:01 PM »
It takes a 80m high column of water at 4-5deg C to melt a single meter of ice. Melting of ice takes so much energy that it just takes a lot of time. The temperature of sea surface is some factor, but IMHO is not that important.

Freegrass

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Re: The 2019 melting season
« Reply #4587 on: July 25, 2019, 08:17:10 PM »
The residual cap can also eventually split and splinter into large separated units just before disappearing completely
I guess that could happen with a bipole late in the season when the ice is weak. And from what I read here I guess the ice isn't that strong anymore. So I could see it happen, that the whole top comes off and a big piece floats away. But my instinct tells me that the rotation of the earth and cohesive attraction will keep the pack mostly together.

Then there's only the question if Greenland has enough mass to pull the ice pack towards it. Why does the water flow out of the fram strait? Is the water higher around Greenland than it is around the Bering strait?
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UCMiami

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Re: The 2019 melting season
« Reply #4588 on: July 25, 2019, 09:27:15 PM »
The breakup of the NE CAA is quite impressive - open water and large channel wide cracks throughout:

Rich

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Re: The 2019 melting season
« Reply #4589 on: July 25, 2019, 09:28:34 PM »
The residual cap can also eventually split and splinter into large separated units just before disappearing completely
I guess that could happen with a bipole late in the season when the ice is weak. And from what I read here I guess the ice isn't that strong anymore. So I could see it happen, that the whole top comes off and a big piece floats away. But my instinct tells me that the rotation of the earth and cohesive attraction will keep the pack mostly together.

Then there's only the question if Greenland has enough mass to pull the ice pack towards it. Why does the water flow out of the fram strait? Is the water higher around Greenland than it is around the Bering strait?

I would recommend using the Stupid Questions thread for your questions. The title of the thread is misleading. It's for good questions as well.

The circulation goes in both directions through Fram. The outgoing fresh water is on the surface adjacent to Greenland while the incoming denser saltier water comes in at depth adjacent to Svalbard.

The outgoing water is part of the AMOC circulation. It reaches the N. Atlantic and sinks due to a density gradient.

If you want to understand ocean circulation patterns, this is probably not the thread for it.

The question of gravitational attraction to Greenland is also pretty esoteric relative to 2019 melt season. I don't think it would be a big factor. Eurasian land mass would counter that.


petm

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Re: The 2019 melting season
« Reply #4590 on: July 25, 2019, 09:49:23 PM »
Chukchi is now empty, far earlier than ever before.

UCMiami

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Re: The 2019 melting season
« Reply #4591 on: July 25, 2019, 10:00:56 PM »
Just be aware that this graph is I believe the whipneus definition of the Chukchi that uses a more southern definition of the sea than the one used by NSIDC/JAXA. (I learned the distinction this year!)

Greenbelt

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Re: The 2019 melting season
« Reply #4592 on: July 25, 2019, 10:04:51 PM »
Ice in the Greenland Sea likely to take a beating as the heatwave shifts up to Scandinavia and then west to merge with the Polar High.  I'm very curious to watch what happens all along the Atlantic ice front this next week.

petm

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Re: The 2019 melting season
« Reply #4593 on: July 25, 2019, 10:05:04 PM »
Thanks for the distinction. I prefer Wip's definitions, always.  :D

Regardless of where one draws the lines, with the wind / hot air / warm waves event currently in the W. Beaufort and N. Chukchi, little will be left in the vicinity for long.

petm

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Re: The 2019 melting season
« Reply #4594 on: July 25, 2019, 10:07:04 PM »
In other news, is it normal for the arctic jet to form a loop?


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Re: The 2019 melting season
« Reply #4595 on: July 25, 2019, 10:08:48 PM »
I found a close-up of the ice between Wrangel and the New Siberian Islands. I took a picture in Worldview for context (it's upside-down relative to the Sentinel image). This ice looks absolutely awful. The large floe is about 12 km across and barely hanging together.

https://apps.sentinel-hub.com/sentinel-playground/?source=S2&lat=70.91506958513088&lng=170.16517639160156&zoom=11&preset=CUSTOM&layers=B01,B02,B03&maxcc=31&gain=1.0&gamma=1.0&time=2019-01-01%7C2019-07-25&atmFilter=&showDates=true&evalscript=cmV0dXJuIFtCOEEqMixCMDMqMSxCMDIqMV0%3D&showImage


petm

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Re: The 2019 melting season
« Reply #4596 on: July 25, 2019, 10:14:50 PM »
After a period of relative immobility, impressive ice movement today.

http://osisaf.met.no/p/osisaf_hlprod_qlook.php?prod=LR-Drift

Alphabet Hotel

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Re: The 2019 melting season
« Reply #4597 on: July 25, 2019, 10:15:46 PM »
Ice in the Greenland Sea likely to take a beating as the heatwave shifts up to Scandinavia and then west to merge with the Polar High.  I'm very curious to watch what happens all along the Atlantic ice front this next week.
With every run of the models things seem to get worse and worse. Peeks through the clouds when you can get them basically show an unfolding disaster under there already, even without this next hit.

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Re: The 2019 melting season
« Reply #4598 on: July 25, 2019, 10:18:08 PM »
Just be aware that this graph is I believe the whipneus definition of the Chukchi that uses a more southern definition of the sea than the one used by NSIDC/JAXA. (I learned the distinction this year!)
True, but Wip's graph is still comparing "apples to apples".  His prior year data is using the same grid.
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Re: The 2019 melting season
« Reply #4599 on: July 25, 2019, 10:24:48 PM »
Just be aware that this graph is I believe the whipneus definition of the Chukchi that uses a more southern definition of the sea than the one used by NSIDC/JAXA. (I learned the distinction this year!)

Yes. NSIDC still has 140k km2 remaining. Basically the 75N - 80N zone.