Support the Arctic Sea Ice Forum and Blog

Author Topic: The 2019 melting season  (Read 1219912 times)

binntho

  • Nilas ice
  • Posts: 1096
    • View Profile
  • Liked: 282
  • Likes Given: 76
Re: The 2019 melting season
« Reply #3700 on: July 11, 2019, 07:48:48 AM »
1.  The CAA in 2012 almost entirely melted out.

This summer we are not going to come anywhere near that.
...
even if we do it still probably won't be enough to bring us within a hundred thousand of 2012 extent wise in the CAA.

Its likely 2019 finishes at least 150K higher in extent than 2012.  Maybe more.
I'm not sure I agree about this - the CAA may well end up with more ice than 2012 but I can't see that being a clincher. Seasonal reduction in SIE has only just started in the CAA so it's a bit early to make any definite pronouncements on the results there, and the difference between the various years' minimum is only in the region of a couple of 100k, maybe 5% at most of the expected minimum for the entire Arctic.

Even a small change in wind direction in the CAB proper can increase/decrease SIE by that amount.


2.  The Beaufort/SW CAB is going to be a major road block.  2012 was much warmer in that region than 2019 so far and through July 28th.

Within a few days the wind looks like it will start a fairly consistent push northwards in the Beaufort, with a growing low-pressure over the Laptev/ESS area. So SIE in the Beaufort might drop quite sharply without much more melt in that area?


I think 2019 finishes second to 2012.

I tend to agree, but it's still (fairly) early days, and exciting things might still happen in the next couple of months even if the foreacasts for the next week or two don't seem all that melti-inducing.

As for the forecasts, I'm actually quite lost in all your images, Friv. I can understand (I think) that the general spread and relative size of the red vs. the blue areas tell you something very important, but I'm totally lost as to what it is. Expertise is a fantastic thing, but if you had time to put some effort into explaining your images (perhaps in a seperate thread, and not every time) I for one would be extremely thankful.
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27
Re: The 2019 melting season
« Reply #3701 on: July 11, 2019, 08:02:31 AM »
The ice feeding into the Beaufort comes via the gyre.

I don't think that's quite accurate. They gyre activated early this year and actually caused early loss of Beaufort extent. The ice currently in the Beaufort was due to this trend being reversed by repeated cyclones that reversed the ice direction / compaction, pushing it back out towards shore. Thus if the gyre took hold without interruption it would clear out the Beaufort, not replenish it.

Just watch WorldView May-June and note the movement of ice under the gyre and what happens after cyclones.

https://go.nasa.gov/2l6zxoP

Personally I also think that additional cyclones would have the same result. Due to the process described above, there is very little ice remaining in the adjacent CAB to replenish the Beaufort even if the ice were to move in that direction, and a lot of heat in adjacent surface waters.


Aluminium

  • Frazil ice
  • Posts: 445
    • View Profile
  • Liked: 381
  • Likes Given: 264
Re: The 2019 melting season
« Reply #3702 on: July 11, 2019, 08:14:36 AM »
July 6-10.

2018.

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27

sark

  • Frazil ice
  • Posts: 403
  • not a scientist
    • View Profile
  • Liked: 176
  • Likes Given: 77
Re: The 2019 melting season
« Reply #3704 on: July 11, 2019, 08:17:44 AM »
Friv, that pattern change forecast by so many is turning for the worse already.  GFS has now revealed that it is expecting TWINS!

GFS 00Z 7/11 splits completely to hell throughout the whole 2 week period. 

Big ridges expected from Beringia/Scandinavia before 240 hours.
I am not a scientist

Rich

  • Guest
Re: The 2019 melting season
« Reply #3705 on: July 11, 2019, 09:56:23 AM »
July 6-10.

2018.

Your gifs are awesome Aluminum. Thank you.


oren

  • Young ice
  • Posts: 4538
    • View Profile
  • Liked: 916
  • Likes Given: 1307
Re: The 2019 melting season
« Reply #3706 on: July 11, 2019, 10:04:28 AM »
July 6-10.

2018.
Thank you for these ongoing animations.
Wow. The destruction along the Siberian front over only 4 days is simply astounding. It appears like ice movement at first glance, but for example when focusing on the disconnected ice in the Laptev you can see that only the southern edge is moving while the northern edge is static. I think this is the remnant of the Laptev fast ice. The damage was done over several weeks, but the result became visible when thickness finally got to zero. A quick look at the AMSR2 area charts for Laptev and ESS shows the sudden crash, sudden in 2D but not in 3D.
In addition, it appears that the leading floes in the Beaufort have visibly shrunk.

be cause

  • Grease ice
  • Posts: 893
  • Citizenship .. a Lurker gets asylum
    • View Profile
  • Liked: 262
  • Likes Given: 219
Re: The 2019 melting season
« Reply #3707 on: July 11, 2019, 10:18:29 AM »
^^^ ESS ? .. that is a cliff ! b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

ArcticMelt2

  • Frazil ice
  • Posts: 499
    • View Profile
  • Liked: 66
  • Likes Given: 28
Re: The 2019 melting season
« Reply #3708 on: July 11, 2019, 10:37:16 AM »
Strong drift resumed (

Frivolousz21

  • Nilas ice
  • Posts: 1507
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 140
  • Likes Given: 2
Re: The 2019 melting season
« Reply #3709 on: July 11, 2019, 11:24:37 AM »
If the current forecast for correct there will be a lot of compaction in the Beaufort sea next week.

But the euro just brushes the vortex off and back to ridgeland.

Hardly any cold pool to speak of.

I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

be cause

  • Grease ice
  • Posts: 893
  • Citizenship .. a Lurker gets asylum
    • View Profile
  • Liked: 262
  • Likes Given: 219
Re: The 2019 melting season
« Reply #3710 on: July 11, 2019, 12:28:51 PM »
 so the wind is back even before it is gone .. the melt was over , until the next forecast ..
We are about 1/2 way through the melting season , primed to be a monster months ago . Each forecast is like a line in a play .. it is not a paragraph nor an act nor a whole play in itself . And each line keeps getting rewritten .
  The play rolls on ; as the plot thickens the ice thins .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

Rich

  • Guest
Re: The 2019 melting season
« Reply #3711 on: July 11, 2019, 12:50:23 PM »
so the wind is back even before it is gone .. the melt was over , until the next forecast ..
We are about 1/2 way through the melting season , primed to be a monster months ago . Each forecast is like a line in a play .. it is not a paragraph nor an act nor a whole play in itself . And each line keeps getting rewritten .
  The play rolls on ; as the plot thickens the ice thins .. b.c.

Definitely no shortage of drama here.

As the ocean heat slowly creeps from.the Canadian coast toward the Beaufort gyre. Will it be devoured?

Tune in tomorrow.....

Sterks

  • Guest
Re: The 2019 melting season
« Reply #3712 on: July 11, 2019, 12:58:53 PM »
Strong drift resumed (
Yeah and in the worst of it as we speak, will be dying out in the next 24-48 h.
I wonder if this crushing will set the 1 million km2 loss in 5 days on NSIDC extent today or tomorrow, I know it's silly but sort of unprecedented (2007 had it but with the help of the 1st of the month correction).

Frivolousz21

  • Nilas ice
  • Posts: 1507
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 140
  • Likes Given: 2
Re: The 2019 melting season
« Reply #3713 on: July 11, 2019, 01:09:35 PM »

The ESS is collapsing is at its very end now.

It's really amazing to see on satellite you can see the ice just crushed. 

It's got that Flat Dark rubbly look.  Usually when ice reaches a half a meter stick or less it reaches that point.

you can see bigger loads mixed in with that but right now the ESS is being completely decimated bye Zeus level Heat.

and in a few days a decent lie powerful Vortex is going to park its ass over the ESS.


We might see a little bit of a weaker slower ending to the ESS similar to the great article Cyclone of 2012.

either way in the ESS is gone in this world text coming in is going to bring Warm southerly Winds to the Western Cab.

It is likely by July 16th to 17th that 2019 might separate itself from the pack is the lowest by quite a bit if we see a collapse of the ESS and parts of the Western Cab.


Stay tuned for more drama and action next time on frivolous Channel 5.


Most of the ESS is over 3 degrees Celsius at the surface.

you can see the Dome of heat pressing end there's enough wind to create mixing this is absolutely treacherous for the ESS.


3 degrees Celsius is enough to melt 10 cm of ice a day off the top.


Not only that with the decent winds and already warm sea surface temperatures in the area there is bottom. Going on as well.

we really could see the ESS completely collapsed over the next week I'm talking like a half a million square kilometers of extent maybe up to a million.


I don't know this isn't like The Great Arctic cyclone but the heat that's in the ice and heat that is around the ice is unprecedented so maybe this week or Vortex will be enough to stir things up to cause some collapse.

2019 is going to come very close to a new record.


We have to remember all the snow on the ice has been melted off there is nowhere that the Albedo isn't down to Bare ice level.


so to end this post if we do see the collapse of the ESS in the next few days all bets are off
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

petm

  • Grease ice
  • Posts: 675
    • View Profile
  • Liked: 335
  • Likes Given: 27
Re: The 2019 melting season
« Reply #3714 on: July 11, 2019, 01:35:31 PM »
Strong drift resumed (

Looks like compaction. Watch the Laptev bite grow...

uniquorn

  • Nilas ice
  • Posts: 1639
    • View Profile
  • Liked: 790
  • Likes Given: 164
Re: The 2019 melting season
« Reply #3715 on: July 11, 2019, 01:48:25 PM »
worldview terra modis overlayed with unihamburg amsr2-uhh at 35% transparency, may1-jul10. amsr2 100% concentration has been set to transparent to allow worldview features to show through. There is some misalignment in floe movement, probably due to images formed at different hours during the day. This method helps to continue to see ice movement 'through the clouds'
Large format to show detail, best viewed full screen. (double click)
Both sets of images have small contrast adjustment.
edit: Much of the 'blueing' is from the amsr2 layer, indicating lower concentration ice, slightly darker due to the contrast adjustment
added amsr2-uhh, jul10 for clarification
« Last Edit: July 11, 2019, 09:25:56 PM by uniquorn »

Shared Humanity

  • Young ice
  • Posts: 3981
    • View Profile
  • Liked: 430
  • Likes Given: 52
Re: The 2019 melting season
« Reply #3716 on: July 11, 2019, 02:17:50 PM »


While the Chukchi has melted out much sooner than previous years, many of these same years still approached zero ice by the end of the melt season. I think the early melt out has far more implications for the next freeze season as the waters have warmed more than previous years. I would expect the Chukchi to struggle to freeze and the thickness of the ice at the end of the freeze season will be an all time low.

Shared Humanity

  • Young ice
  • Posts: 3981
    • View Profile
  • Liked: 430
  • Likes Given: 52
Re: The 2019 melting season
« Reply #3717 on: July 11, 2019, 02:23:31 PM »
But I think the Beaufort will melt out this year regardless of all the export it received

I'm not sure this is fully logical. The ice feeding into the Beaufort comes via the gyre. Unless there's something that will stop that, so long as there is ice in the central basin there should be at least some ice in the Beaufort, no? It may even be the case during a true BOE it's the last place ice exists, caught up in the vortex. The ice just north of Greenland and Ellesmere tends to end up going out the Fram or down the Nares, but the stuff further north tends to get shunted back towards Beaufort.

Hmmm...

Despite continuous export of ice from the CAB into the Beaufort, the effects of which can be seen on the attached graph, the Beaufort is still at or near a record low and the ice is getting chewed up by the warm waters. Melt has been keeping up with aggressive import.

I would expect only a few MYI ice flows to survive this melt season.

Frivolousz21

  • Nilas ice
  • Posts: 1507
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 140
  • Likes Given: 2
Re: The 2019 melting season
« Reply #3718 on: July 11, 2019, 02:35:33 PM »


While the Chukchi has melted out much sooner than previous years, many of these same years still approached zero ice by the end of the melt season. I think the early melt out has far more implications for the next freeze season as the waters have warmed more than previous years. I would expect the Chukchi to struggle to freeze and the thickness of the ice at the end of the freeze season will be an all time low.

This might be the beginning of the interior having issues refreezing completely.


We knew this day was coming. 

Where were you when the Bering ice ended.
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

El Cid

  • Grease ice
  • Posts: 622
    • View Profile
  • Liked: 196
  • Likes Given: 48
Re: The 2019 melting season
« Reply #3719 on: July 11, 2019, 02:38:29 PM »
Slater model update. Not much of a change, projecting 4,26 M sq km extent by Aug 30, 2019.

For comparison:

NSIDC extent on Aug 30 of

2012: 3,78
2016: 4,56
2007: 4,72
2017: 4,95

Rich

  • Guest
Re: The 2019 melting season
« Reply #3720 on: July 11, 2019, 02:47:31 PM »


While the Chukchi has melted out much sooner than previous years, many of these same years still approached zero ice by the end of the melt season. I think the early melt out has far more implications for the next freeze season as the waters have warmed more than previous years. I would expect the Chukchi to struggle to freeze and the thickness of the ice at the end of the freeze season will be an all time low.

And every year the GHG blanket gets thicker, making it tougher for the accumulated heat to escape.

Its a vicious cycle and becoming increasingly difficult to imagine humans turning it around.

The water in those Alaskan bays which face the Bering Strait are now up to ~ 15C according to GFS. That"s just ridiculous. Bring your swim suit.

Glenn_Tamblyn

  • New ice
  • Posts: 9
    • View Profile
  • Liked: 4
  • Likes Given: 0
Re: The 2019 melting season
« Reply #3721 on: July 11, 2019, 02:49:07 PM »

The ESS is collapsing is at its very end now.

It's really amazing to see on satellite you can see the ice just crushed. 

It's got that Flat Dark rubbly look.  Usually when ice reaches a half a meter stick or less it reaches that point.

you can see bigger loads mixed in with that but right now the ESS is being completely decimated bye Zeus level Heat.

and in a few days a decent lie powerful Vortex is going to park its ass over the ESS.


We might see a little bit of a weaker slower ending to the ESS similar to the great article Cyclone of 2012.

either way in the ESS is gone in this world text coming in is going to bring Warm southerly Winds to the Western Cab.

It is likely by July 16th to 17th that 2019 might separate itself from the pack is the lowest by quite a bit if we see a collapse of the ESS and parts of the Western Cab.


Stay tuned for more drama and action next time on frivolous Channel 5.


Most of the ESS is over 3 degrees Celsius at the surface.

you can see the Dome of heat pressing end there's enough wind to create mixing this is absolutely treacherous for the ESS.


3 degrees Celsius is enough to melt 10 cm of ice a day off the top.


Not only that with the decent winds and already warm sea surface temperatures in the area there is bottom. Going on as well.

we really could see the ESS completely collapsed over the next week I'm talking like a half a million square kilometers of extent maybe up to a million.


I don't know this isn't like The Great Arctic cyclone but the heat that's in the ice and heat that is around the ice is unprecedented so maybe this week or Vortex will be enough to stir things up to cause some collapse.

2019 is going to come very close to a new record.


We have to remember all the snow on the ice has been melted off there is nowhere that the Albedo isn't down to Bare ice level.


so to end this post if we do see the collapse of the ESS in the next few days all bets are off

Friv, if your upper estimate for the ESS is right, that isn't just the ESS gone, it is 300,000 off the CAB as in Wipneus' latest extent graphs. Which just about puts that at record lows as well.

Ice Shieldz

  • Frazil ice
  • Posts: 234
    • View Profile
  • Liked: 41
  • Likes Given: 29
Re: The 2019 melting season
« Reply #3722 on: July 11, 2019, 02:50:59 PM »
worldview terra modis overlayed with unihamburg amsr2-uhh at 35% transparency, may1-jul10. <snip>
Wow this is one of the best visualizations to date uniquorn - thank you. The last frame shows clearly extensive bluing (melt ponding?) of the ice. Looks like serious poof to some come.

binntho

  • Nilas ice
  • Posts: 1096
    • View Profile
  • Liked: 282
  • Likes Given: 76
Re: The 2019 melting season
« Reply #3723 on: July 11, 2019, 02:53:23 PM »
worldview terra modis overlayed with unihamburg amsr2-uhh at 35% transparency, may1-jul10. <snip>
Wow this is one of the best visualizations to date uniquorn - thank you. The last frame shows clearly extensive bluing (melt ponding) of the ice. Looks like serious poof to some come.
+1 (x10)

Agree totally, fantastic animation and truly scary last couple of frames.
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

uniquorn

  • Nilas ice
  • Posts: 1639
    • View Profile
  • Liked: 790
  • Likes Given: 164
Re: The 2019 melting season
« Reply #3724 on: July 11, 2019, 03:13:22 PM »
The last frame shows clearly extensive bluing (melt ponding?) of the ice. Looks like serious poof to some come.
Most of the 'bluing' is from the amsr2 layer, indicating lower concentration ice, slightly darker due to the contrast adjustment, but it is still bad news.

RikW

  • Frazil ice
  • Posts: 179
    • View Profile
  • Liked: 19
  • Likes Given: 10
Re: The 2019 melting season
« Reply #3725 on: July 11, 2019, 03:26:04 PM »
it's kind of frightening seeing parts of the arctic going *poof* in the last couple of days/weeks especially seeing the state of the ice and imagining more ice going *poof*

Thomas Barlow

  • Frazil ice
  • Posts: 103
    • View Profile
  • Liked: 25
  • Likes Given: 22
Re: The 2019 melting season
« Reply #3726 on: July 11, 2019, 05:14:58 PM »
Arctic Basin decline in sea-ice extent.
Graph by Wipneus.
https://tinyurl.com/y2b74omj

ArcticMelt2

  • Frazil ice
  • Posts: 499
    • View Profile
  • Liked: 66
  • Likes Given: 28
Re: The 2019 melting season
« Reply #3727 on: July 11, 2019, 05:20:01 PM »
Important picture. Warming in the summer in the Arctic could be much more if not for forest fires.

https://twitter.com/AlaskaWx/status/1149321962004475906

Quote
Thursday is the 17th day in Fairbanks with smoke significantly reducing visibility. The frequency of smoky summers has increased sharply: between 1952 & 2000, summers with ≥15 smoky days occurred only 3 times. Since 2000, this is now the 6th. #akwx @Climatologist49 @TScottRupp





On the other hand, fires reduce the ability of the biosphere to accumulate carbon.

Freegrass

  • Frazil ice
  • Posts: 289
  • Worried Warrior
    • View Profile
  • Liked: 160
  • Likes Given: 165
Re: The 2019 melting season
« Reply #3728 on: July 11, 2019, 05:20:35 PM »
Hi everyone. I'm an amateur who's been following the climate for many years now, but I've just started reading this 2019 melting season blog, and I find it fascinating. I've learned so much already, and I thank you all! But I have still so much to learn... I was wondering why there isn't more chatter about this storm the coming days? I've always been using Nullschool to follow the climate a little, and so I'm seeing some serious winds blowing over open water and towards the very weak ice in the ESS in the coming days. Will this wind be strong enough to stir up the water and destroy all that weak ice in its path?

https://earth.nullschool.net/#2019/07/14/0600Z/wind/surface/level/orthographic=-35.80,92.61,2381/loc=135.872,78.052

It also seems like a lot of heat will be pumped right into the center of the ice pack.
 
https://earth.nullschool.net/#2019/07/14/0600Z/wind/isobaric/1000hPa/overlay=temp/orthographic=-35.80,92.61,2381/loc=135.872,78.052

This isn't gonna be good, is it?
« Last Edit: July 11, 2019, 06:22:30 PM by Freegrass »
The Existential Climate Crisis Is Upon Us!

GoSouthYoungins

  • Nilas ice
  • Posts: 1274
    • View Profile
  • Liked: 84
  • Likes Given: 109
Re: The 2019 melting season
« Reply #3729 on: July 11, 2019, 05:25:42 PM »
I don't understand the "2nd is more likely than record" perspective. Every image and graph I look at makes it look like a record is on the only thing on the menu.

I do get that 2012 had a real nice cyclone to mix things up, but I'll be super surprised if the Arctic, with all of the warm open water, doesn't create some serious weather systems in the coming month.
big time oops

Sterks

  • Guest
Re: The 2019 melting season
« Reply #3730 on: July 11, 2019, 05:50:32 PM »
Especially when the Albedo potential and the actual insolation have been well in sync.

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3731 on: July 11, 2019, 05:58:13 PM »
Arctic Basin decline in sea-ice extent.
Graph by Wipneus.
https://tinyurl.com/y2b74omj

If that's not a cliff, what is?   :-\

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3732 on: July 11, 2019, 06:09:13 PM »
Slater model update. Not much of a change, projecting 4,26 M sq km extent by Aug 30, 2019.

Looking at the map, this is all way too optimistic IMHO. It still has >10% on ice in Baffin and Hudson. It sees ice near Svalbard with high confidence. IDK...

philopek

  • Frazil ice
  • Posts: 464
    • View Profile
  • Liked: 209
  • Likes Given: 40
Re: The 2019 melting season
« Reply #3733 on: July 11, 2019, 06:12:48 PM »
Arctic Basin decline in sea-ice extent.
Graph by Wipneus.
https://tinyurl.com/y2b74omj

If that's not a cliff, what is?   :-\

An abyss ? ;)

UCMiami

  • New ice
  • Posts: 76
    • View Profile
  • Liked: 29
  • Likes Given: 39
Re: The 2019 melting season
« Reply #3734 on: July 11, 2019, 06:29:32 PM »
First post from a non-scientific lurker. This site is an amazing resource - thanks to everyone posting such great information and keeping it mostly readable for a neophyte!

I have been spending a lot of time looking at the Worldview arctic images and specifically noting the march north of consistent small open water around flows from the Beaufort into the CAB. Since the end of June these have advanced from around 79N to about 82N. I am assuming this is due to the continual 'export' of ice into the Beaufort from the CAB, but to me indicates that there is no longer enough CAB ice to 'fill in' for that exported ice. People discuss 'false' extent/area drops based on melt ponding, but these small gaps are not ponds but actual open water. I don't know how much of these small areas are actually being picked up by extent/area calculations.

I also see these gaps showing up with greater frequency north of the other export routes - Fram and Barents to a lesser extent and wonder if the large gaps that appeared at the NE of Greenland is a result of a dividing line of Fram export vs. westward drift in the rest of the ice N of Greenland.

My personal conclusion from this is that while earlier in the season export seemed to be driven by a general arctic basin shift toward the Atlantic side, the current situation is that there is no longer 'replenishment' of the CAB ice and the crash in Asian/Eastern European side ice is melt driven and not as much 'compaction north'.

Pragma

  • Frazil ice
  • Posts: 168
    • View Profile
  • Liked: 51
  • Likes Given: 14
Re: The 2019 melting season
« Reply #3735 on: July 11, 2019, 06:31:09 PM »
Looking at the map, this is all way too optimistic IMHO. It still has >10% on ice in Baffin and Hudson. It sees ice near Svalbard with high confidence. IDK...
I agree. As many of us have pointed out, leaping to conclusions is dangerous.

For example, when we had the big drop yesterday, I was going to comment that Hudson was in the middle of a "poof", but forgot.

Well, it "un-poofed" today on the NSIDC extent, just to keep us on our toes. I don't know the Slater model well enough to know what all the inputs are, but things like the Hudson and it's "magic" ice have got to play hell with the statistics.

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3736 on: July 11, 2019, 06:37:47 PM »
I agree. As many of us have pointed out, leaping to conclusions is dangerous.

For example, when we had the big drop yesterday, I was going to comment that Hudson was in the middle of a "poof", but forgot.

Well, it "un-poofed" today on the NSIDC extent, just to keep us on our toes. I don't know the Slater model well enough to know what all the inputs are, but things like the Hudson and it's "magic" ice have got to play hell with the statistics.

For i understand it, it must take past performance into account which means it is biased. Biased from data that only know a state where there is more ice than now.

I think we can assume 10 to 20 per cent optimistic bias.

Sambuccu

  • New ice
  • Posts: 24
    • View Profile
  • Liked: 4
  • Likes Given: 16
Re: The 2019 melting season
« Reply #3737 on: July 11, 2019, 06:41:15 PM »
Slater model update. Not much of a change, projecting 4,26 M sq km extent by Aug 30, 2019.

Looking at the map, this is all way too optimistic IMHO. It still has >10% on ice in Baffin and Hudson. It sees ice near Svalbard with high confidence. IDK...

This map looks like current map. Not end of august forecast map.

DrTskoul

  • Nilas ice
  • Posts: 1451
    • View Profile
  • Liked: 212
  • Likes Given: 60
Re: The 2019 melting season
« Reply #3738 on: July 11, 2019, 06:44:19 PM »
Slater model update. Not much of a change, projecting 4,26 M sq km extent by Aug 30, 2019.

Looking at the map, this is all way too optimistic IMHO. It still has >10% on ice in Baffin and Hudson. It sees ice near Svalbard with high confidence. IDK...

This map looks like current map. Not end of august forecast map.

You do understand this is the current map with the survival probability plotted. Only the blue will survive by end of August and that is the maps prediction

El Cid

  • Grease ice
  • Posts: 622
    • View Profile
  • Liked: 196
  • Likes Given: 48
Re: The 2019 melting season
« Reply #3739 on: July 11, 2019, 06:46:43 PM »
RE : Slater

Yes, the map seems too optimistic to me as well and looking at uni-bremen and comparing it to previous years+considering the "June boom" this year I would think that we are at least on par with 2012. Anyway, you know the rule with models: once you have a model, you don't secondguess it.

Sambuccu: pls read upthread, we've discussed it before. Short answer: consider only the blue pixels.

ArcticMelt2

  • Frazil ice
  • Posts: 499
    • View Profile
  • Liked: 66
  • Likes Given: 28
Re: The 2019 melting season
« Reply #3740 on: July 11, 2019, 06:54:01 PM »
Only the blue will survive by end of August and that is the maps prediction

Blue ice is the current high concentration ice areas:



But the forecast does not take into account ice drift for the remaining two months.

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3741 on: July 11, 2019, 06:56:10 PM »
Only the blue will survive by end of August and that is the maps prediction

The colours indicate the probability of ice being there still in 50 days.

It's not a prediction, it calculates the likelihood.

Villabolo

  • New ice
  • Posts: 53
    • View Profile
    • Global Warming Basics
  • Liked: 9
  • Likes Given: 24
Re: The 2019 melting season
« Reply #3742 on: July 11, 2019, 06:57:26 PM »
Don't mean to get off topic but I attempted to access Bremen University ice concentration map and Hycom ice thickness map for the Arctic and I got a privacy error message warning me of an attack. What's up with that?

Aluminium

  • Frazil ice
  • Posts: 445
    • View Profile
  • Liked: 381
  • Likes Given: 264
Re: The 2019 melting season
« Reply #3743 on: July 11, 2019, 06:57:59 PM »
The ESS lifts up.

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3744 on: July 11, 2019, 06:59:00 PM »
once you have a model, you don't secondguess it.


LOL, sorry! I totally missed the memo! ;)

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3745 on: July 11, 2019, 07:00:59 PM »
Don't mean to get off topic but I attempted to access Bremen University ice concentration map and Hycom ice thickness map for the Arctic and I got a privacy error message warning me of an attack. What's up with that?

They failed to update their SSL Certificate. Just click through. :)

Frivolousz21

  • Nilas ice
  • Posts: 1507
  • Live in Belleville, IL..15 miles SE of St. Louis.
    • View Profile
  • Liked: 140
  • Likes Given: 2
Re: The 2019 melting season
« Reply #3746 on: July 11, 2019, 07:08:55 PM »
I think you guys are
I got a nickname for all my guns
a Desert Eagle that I call Big Pun
a two shot that I call Tupac
and a dirty pistol that love to crew hop
my TEC 9 Imma call T-Pain
my 3-8 snub Imma call Lil Wayne
machine gun named Missy so loud
it go e-e-e-e-ow e-e-e-e-e-e-blaow

b_lumenkraft

  • Guest
Re: The 2019 melting season
« Reply #3747 on: July 11, 2019, 07:09:36 PM »
... brilliant!

aslan

  • Frazil ice
  • Posts: 136
    • View Profile
  • Liked: 56
  • Likes Given: 0
Re: The 2019 melting season
« Reply #3748 on: July 11, 2019, 07:10:14 PM »
To add to the discussion about the begining of the end, June 2019 was the warmest month of June regarding SST in Bering sea and Bering strait according to reanalysis.
Aans as an illustration, Kotzebue is near or above record Tn and Td since 4 days : http://ogimet.com/cgi-bin/gsynres?ind=70133&ano=2019&mes=7&day=11&hora=12&min=0&ndays=30

The transport is strong this year trough the strait, and so the SST are more asymetric than usual, but despite this all the Bering sea and Chuckchi sea are at or above record level, and strong currents are burring this heat to great depth. The chart from the DMI is now saturated with red, after reaching a "low" the 4th. An incredible amount of heat is building into Arctic Ocean, and is now wanting to ease.

Steven

  • Grease ice
  • Posts: 555
    • View Profile
  • Liked: 133
  • Likes Given: 16
Re: The 2019 melting season
« Reply #3749 on: July 11, 2019, 07:34:37 PM »
This map looks like current map. Not end of august forecast map.

It's best to ignore those Slater maps.

The original Slater maps were fine:  Slater calculated the survival probability for each grid point, based on the current NSIDC sea ice concentration and past years' behavior for that grid point.

But it seems that after Slater's death in 2016, someone else has taken over, and the Slater map has been oversimplified.  The map is now lumping together grid points with the same concentration and does NOT take into account the location of the grid points (e.g. whether they are in Hudson Bay or in the Central Arctic).

This was discussed last year too:
https://forum.arctic-sea-ice.net/index.php/topic,2278.msg158317.html#msg158317