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Nick_Naylor

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Re: The 2015 melting season
« Reply #3150 on: August 07, 2015, 09:14:14 PM »
You could just say along which longitude line you wish to travel, but that's not very folksy or meaningful to most people. Or name a destination on that longitude line.

ChrisReynolds

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Re: The 2015 melting season
« Reply #3151 on: August 07, 2015, 10:22:00 PM »
'west' of the north pole
A good title for a puzzle book:  "West of the North Pole (and other conundrums)"

I dislike the terms west and east Arctic, although after initial head scratching it occurred to me some years ago that it's mainly just the east and west of the Greenwich meridion - well duh! Although I tend to think in terms of longitudes from 0 to 360, certainly Google Earth does it as, say  120deg West (or East).

Of course, assuming you're facing the pole, west is clockwise...

er...

I think...

 ;)

jdallen

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Re: The 2015 melting season
« Reply #3152 on: August 07, 2015, 10:42:39 PM »
You could just say along which longitude line you wish to travel, but that's not very folksy or meaningful to most people. Or name a destination on that longitude line.
By default, I use the hemisphere for reference.  "East" is east of 0 longitude, to 180.  Keeps it simple, in my view. It also explains why weatherdude88 and I were talking past one another.  :P
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Andreas T

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Re: The 2015 melting season
« Reply #3153 on: August 07, 2015, 10:53:17 PM »
So if you are in the Bering sea and the wind is blowing from the west does it come from eastern Siberia or from western Alaska?

Nick_Naylor

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Re: The 2015 melting season
« Reply #3154 on: August 07, 2015, 11:05:10 PM »
my brain hurts :o

Tensor

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Re: The 2015 melting season
« Reply #3155 on: August 07, 2015, 11:09:20 PM »
So if you are in the Bering sea and the wind is blowing from the west does it come from eastern Siberia or from western Alaska?

If the wind is coming from tomorrow, it's from Siberia, if it's today's wind, it's from Western Alaska.
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AmbiValent

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Re: The 2015 melting season
« Reply #3156 on: August 07, 2015, 11:10:52 PM »
The Western Goths live in the East?
Bright ice, how can you crack and fail? How can the ice that seemed so mighty suddenly seem so frail?

Laurent

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Re: The 2015 melting season
« Reply #3157 on: August 07, 2015, 11:20:49 PM »
There is an opening feature near the pole that may be worth to watch.
If Hycom is true (not sure ok ok) the ice is around 1 m thick in the whole area.

Gonzo

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Re: The 2015 melting season
« Reply #3158 on: August 08, 2015, 12:01:14 AM »
Quote
Andreas T
So if you are in the Bering sea and the wind is blowing from the west does it come from eastern Siberia or from western Alaska?

Don't know. Ask Sarah Palin.
She keeps a careful watch on Russia from her house.
« Last Edit: August 08, 2015, 12:06:31 AM by Gonzo »

jdallen

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Re: The 2015 melting season
« Reply #3159 on: August 08, 2015, 12:23:32 AM »
There is an opening feature near the pole that may be worth to watch.
If Hycom is true (not sure ok ok) the ice is around 1 m thick in the whole area.
Not sure about Hycom, but if look at the same area from that point back in the direction of the Chukchi on August 6th you will see multiple areas starting to open up.

I expect it so from a combination of movement combined with thin lead ice starting to melt out.

It does also have one wonder if we have Atlantic flow starting to make its presence felt under the ice.
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Greenbelt

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Re: The 2015 melting season
« Reply #3160 on: August 08, 2015, 02:49:27 AM »
GFS continues to advertise a lot of storminess on the Alaskan and Beaufort side.  ECMWF doesn't seem as enthusiastic. I'm not qualified to prognosticate, but my notion is that wind and water are much more important for melting than sun during August. We'll see!

Greenbelt

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Re: The 2015 melting season
« Reply #3161 on: August 08, 2015, 03:00:09 AM »
Also noticed that there's still some top melt at the "north pole" buoy site (86n I believe, between the pole and Fram Strait). Couple centimeters per day it looks like. Note, these images will keep updating as the camera keeps sending pics, so this top melt idea may be proved inaccurate after a while...


slow wing

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Re: The 2015 melting season
« Reply #3162 on: August 08, 2015, 03:20:16 AM »
So if you are in the Bering sea and the wind is blowing from the west does it come from eastern Siberia or from western Alaska?
The former. From the West is from the Russian side. (Not sure how well the compass is pointing North in the image but it gives the general idea.)


Phil.

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Re: The 2015 melting season
« Reply #3163 on: August 08, 2015, 03:32:44 AM »
Also noticed that there's still some top melt at the "north pole" buoy site (86n I believe, between the pole and Fram Strait). Couple centimeters per day it looks like. Note, these images will keep updating as the camera keeps sending pics, so this top melt idea may be proved inaccurate after a while...


Had visitors in the second picture (08/05 2259:29).

slow wing

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Re: The 2015 melting season
« Reply #3164 on: August 08, 2015, 03:59:28 AM »
Some of the peek-a-boo ice in the Beaufort Sea hole is appearing again in today's U. Bremen update, as it flits back across the concentration threshold.

The ice off Greenland's East coast continues to decay away, including in the Northern part above 80 degrees North. Otherwise, no other obvious regions of ice loss.

Click on gif to flash back for comparison to yesterday's map...


12Patrick

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Re: The 2015 melting season
« Reply #3165 on: August 08, 2015, 05:07:44 AM »
Some of the peek-a-boo ice in the Beaufort Sea hole is appearing again in today's U. Bremen update, as it flits back across the concentration threshold.The ice off Greenland's East coast continues to decay away, including in the Northern part above 80 degrees North. Otherwise, no other obvious regions of ice loss.

Click on gif to flash back for comparison to yesterday's map...
It shows more ice on th 7th than on the 6th...
« Last Edit: August 08, 2015, 02:58:24 PM by 12Patrick »

Gonzo

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Re: The 2015 melting season
« Reply #3166 on: August 08, 2015, 05:33:24 AM »
Quote
Greenbelt
Also noticed that there's still some top melt at the "north pole" buoy site
The north pole doesn't seem to ever do anything interesting.

Quote
Had visitors?
They probly live there in a hut.

-- Gonzo.
« Last Edit: August 08, 2015, 06:37:31 AM by Gonzo »

Gonzo

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Re: The 2015 melting season
« Reply #3167 on: August 08, 2015, 05:46:07 AM »
Great job showing that big yellow-red fissure on the concentration map, from NE Greenland out to far "west" (whatever these maypole dancers want to call it).
That thing goes way west, and could be a fissure from Atlantic side, all the way to Beaufort for the first time ever.
It shows up in all concentration, satellite, and extent/area maps right now, and goes all the way across.
It is gonzo I think, all the way through, by mid September I think.

It should be called the "Gonzo Passage".

ChrisReynolds

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Re: The 2015 melting season
« Reply #3168 on: August 08, 2015, 07:48:54 AM »
There is an opening feature near the pole that may be worth to watch.
If Hycom is true (not sure ok ok) the ice is around 1 m thick in the whole area.

Laurent,

See my long post at the top of this page. The ice is not all 1m thick, that will be something like average or modal thickness, the model will have a sub grid thickness distribution like PIOMAS and will likely include a lot of open water within the grid box.

jdallen

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Re: The 2015 melting season
« Reply #3169 on: August 08, 2015, 09:37:38 AM »
Well, *sure* the ice extent on the right side of this image is 70% +/- a little.

But is it really Arctic Pack?!

 :-\ :P
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seaicesailor

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Re: The 2015 melting season
« Reply #3170 on: August 08, 2015, 10:05:23 AM »
Great job showing that big yellow-red fissure on the concentration map, from NE Greenland out to far "west" (whatever these maypole dancers want to call it).
That thing goes way west, and could be a fissure from Atlantic side, all the way to Beaufort for the first time ever.
It shows up in all concentration, satellite, and extent/area maps right now, and goes all the way across.
It is gonzo I think, all the way through, by mid September I think.

It should be called the "Gonzo Passage".
More names.
Ive seen it in MODIS. The thing is, whatever it is, will be gone by 2016, and if it opens up, will be as easy to get closed again.
The insult was uncalled for.

You know you can put an official name to a Moons feature by paying some money? It will surely last longer than one in the Arctic ice.

Edit: you can name stars, not Moon features. Even better.
« Last Edit: August 08, 2015, 10:28:04 AM by seaicesailor »

6roucho

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Re: The 2015 melting season
« Reply #3171 on: August 08, 2015, 10:28:18 AM »
Maypole dancers is a cute analogy. Clockwise dancers move towards the east. Anticlockwise dancers move toward the west. None are in the east or west, other than by an arbitrary convention.

Laurent

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Re: The 2015 melting season
« Reply #3172 on: August 08, 2015, 10:43:39 AM »
I was wondering what these algae were doing there !
May be there is a flow from Beaufort to Fram or from Pacific like Paul Beckwith is saying, because of the higher height between the pacific and east of Greenland (enhanced by melting of Zachariae Isbrae and 79north ?).
http://www.the-cryosphere-discuss.net/1/41/2007/tcd-1-41-2007.pdf
http://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticssh_nowcast_anim30d.gif
Well, if that flow gets bigger, it may cut the ice completely, no way to escape...
« Last Edit: August 08, 2015, 11:12:40 AM by Laurent »

Jim Hunt

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Re: The 2015 melting season
« Reply #3173 on: August 08, 2015, 11:08:28 AM »
Also noticed that there's still some top melt at the "north pole" buoy site (86n I believe, between the pole and Fram Strait).

Here's the latest temperature profiles from buoy 2015D. It's just getting to the stage where significant bottom melt can get going:

http://GreatWhiteCon.info/resources/ice-mass-balance-buoys/summer-2015-imbs/#2015D-Temp

It was showing 41 cm of surface melt and 19 cm of bottom melt yesterday. Remaining thickness on August 7th was 146 cm, so it's lost 6cm in one day.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

seaicesailor

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Re: The 2015 melting season
« Reply #3174 on: August 08, 2015, 02:09:43 PM »

A third small storm from Siberia predicted to hit Chukchi in 4 days or so, then Beaufort/CAB. Won't help to lose extent but wont help survival of free-drifting floes.

Still after ten days of this weather, where is the "significant slowdown"? See IJIS today. Call it normal August slowdown.
 I am ready for a significant speedup later given the bottom melting/ compaction potential. We'll see.


greatdying2

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Re: The 2015 melting season
« Reply #3175 on: August 08, 2015, 02:52:01 PM »
Stir it up.
The Permian–Triassic extinction event, a.k.a. the Great Dying, occurred about 250 million years ago and is the most severe known extinction event. Up to 96% of all marine species and 70% of terrestrial vertebrate species became extinct; it is also the only known mass extinction of insects.

Neven

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Re: The 2015 melting season
« Reply #3176 on: August 08, 2015, 03:13:30 PM »
The ECMWF is showing a somewhat stronger sign of Dipole formation, but it's still 5-7 days out (and so I won't bother posting the SLP forecast plot). Compaction can be a very important component of the final minimum.
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Richard Rathbone

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Re: The 2015 melting season
« Reply #3177 on: August 08, 2015, 03:22:47 PM »
There is an opening feature near the pole that may be worth to watch.
If Hycom is true (not sure ok ok) the ice is around 1 m thick in the whole area.

Laurent,

See my long post at the top of this page. The ice is not all 1m thick, that will be something like average or modal thickness, the model will have a sub grid thickness distribution like PIOMAS and will likely include a lot of open water within the grid box.

The default thickness distribution in CICE is 5 thickness layers (plus open water). However, CICE is a model for developing whatever distribution the user specifies and unless the users of CICE document how they are using it, its impossible to say how many there are in a particular implementation. (CICE documentation at http://oceans11.lanl.gov/trac/CICE)

Gonzo

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Re: The 2015 melting season
« Reply #3178 on: August 08, 2015, 06:44:32 PM »
What do people think of this?
I saw the maps for Aug. 7, 2015 and 2012, and I thought they look very different, so I made this graphic to show what I mean.
Am I imagining it? With at least a month to go, will this make a difference in the final outcome?
If the melt season extends longer and warmer, which I think it will due to global record heat being set all over the place, can these weaknesses amalgamate and cause a break up of the ice sheet into 3 or 4 big parts?
« Last Edit: August 08, 2015, 06:54:39 PM by Gonzo »

Gonzo

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Re: The 2015 melting season
« Reply #3179 on: August 08, 2015, 07:07:42 PM »
Compare the above, to where 2012 ended up by mid-sept.

Jim Hunt

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Re: The 2015 melting season
« Reply #3180 on: August 08, 2015, 07:22:51 PM »
Here's the latest edition of the GWC Beaufort Sea video:

Reality is merely an illusion, albeit a very persistent one - Albert Einstein

ChrisReynolds

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Re: The 2015 melting season
« Reply #3181 on: August 08, 2015, 07:43:15 PM »
There is an opening feature near the pole that may be worth to watch.
If Hycom is true (not sure ok ok) the ice is around 1 m thick in the whole area.

Laurent,

See my long post at the top of this page. The ice is not all 1m thick, that will be something like average or modal thickness, the model will have a sub grid thickness distribution like PIOMAS and will likely include a lot of open water within the grid box.

The default thickness distribution in CICE is 5 thickness layers (plus open water). However, CICE is a model for developing whatever distribution the user specifies and unless the users of CICE document how they are using it, its impossible to say how many there are in a particular implementation. (CICE documentation at http://oceans11.lanl.gov/trac/CICE)

Thanks, it's useful to have a copy of the manual, I've had one for a while but must admit I haven't properly read it.

I would imagine that DMI and US Navy are using more than 5 sub grid thickness layers. 5 layers will make sense in a global model simulation where you want results about say 2050 sometime before 2050.  ;) OK, I exagerate there...

It wouldn't surprise me if US Navy are using more than the 12 PIOMAS uses, both them and Los Alamos have probably got better computing power than the PSC.


Gonzo,

I doubt it will cause a break up as you suggest, but running with ideas and seeing how they play out is part of the fun of learning, so don't let that stop you.

It helps to try to average those plots. Daily changes driven by wind and by errors from cloud cover can cause misleading patterns. Every year I download the Bremen plots daily from May onwards for each day, when I download a new batch I use a photo viewer (the one that comes with Vista) and look at something like the last 7 days, flicking from image to image to try to get a feel for the longer term patterns.

(I wonder whether ImageJ can average a batch of something like seven days...)

Nick_Naylor

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Re: The 2015 melting season
« Reply #3182 on: August 08, 2015, 08:33:33 PM »
(I wonder whether ImageJ can average a batch of something like seven days...)

Probably, even if not specifically provided. If you can stack the images in layers and set opacity for each layer, you can set the top layer's opacity to 1/7 (14%), the next layer to 1/6 (17%), 20%, 25%, 33%, 50% and 100%, giving you an average of the seven layers.

AySz88

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Re: The 2015 melting season
« Reply #3183 on: August 08, 2015, 08:50:18 PM »
(I wonder whether ImageJ can average a batch of something like seven days...)

Probably, even if not specifically provided. If you can stack the images in layers and set opacity for each layer...

I would think this would give you an "average color", which isn't quite what you want (for example: the average of purple+blue would be indigo, when the average of 100% and 0% should be a green/yellow 50%).  So I think you'd need to translate from color to concentration, average, and then translate back.

ChrisReynolds

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Re: The 2015 melting season
« Reply #3184 on: August 08, 2015, 09:27:43 PM »
AzSz88, Nick,

I have a graphics programme that can stack and in which I can change opacity, but that's not the same as averaging.

I guess the thing to do would be to use the native concentration files and work out something like a past 7 day average, this would be a very primitive first step towards the sort of persistence model that Andrew Slater does. I'd have to code up the image drawing*, but the rest of the code I have already got, the averaging operation is trivial.

Yes, now I check ImageJ my memory does serve me well, there is an average option in ImageJ, Process>Image Calculator - set option average. But you can only do average of two images and the result isn't of much use with Bremen, might be better with a true monocolour bitmap.

jdallen

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Re: The 2015 melting season
« Reply #3185 on: August 08, 2015, 10:04:36 PM »
Compare the above, to where 2012 ended up by mid-sept.
It suggests to me the current dynamics are in line with what was going on in 2012. 

It affirms to me that the 2011 and 2007 records are likely to be passed, and if we have a significant weather event, 2012 may still be in play as well.
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Paul Beckwith

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Re: The 2015 melting season
« Reply #3186 on: August 08, 2015, 10:18:39 PM »
I am not sure where to post this, but I think that the extremely warm North Pacific Ocean temperatures (with algae blooms and marine life die-off) is putting lots of warm water into the Arctic. Hansen's recent paper related AMOC and Southern-MOC to ice cap melt but does not say a word about North Pacific-MOC. I discuss this in 2 videos:

@PaulHBeckwith: North #Pacific #Ocean BlowTorch; Part 1/2 https://t.co/at1PRk6P97 #climate #japan2015 #japan #alaska #Vancouver #bcpoli #California #drought

@PaulHBeckwith: North #Pacific Ocean BlowTorch: Part 2/2 https://t.co/oQ8DjDh2xr #climate #climatechange #globalwarming #drought #California #Japan #weather

I am pretty sure that the root cause of the blob is the enormous Arctic Temperature amplification from rapidly declining Arctic sea ice loss and spring snow cover decline, leading to cascading latent heat feedbacks. I elaborate on in the videos. El Niño magnifies the blob but does not cause it. As the El Niño magnifies into fall and winter and the Arctic starts to cool (later than normal) the likelihood of large cyclonic activity heading into the Arctic basin is greater...

Bob Wallace

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Re: The 2015 melting season
« Reply #3187 on: August 08, 2015, 10:27:21 PM »
Just wondering if it adds anything to 'fade' between frames with things like the Bremen maps.  It seems to me to make the day to day ice movement easier to track.



These are the August 6 and 7 images. I didn't take the time to add dates.

I used EZGif to build the gif, add fading, and to crop.  Probably would have to add multiple copies of the first or last frame to create a pause.

http://ezgif.com/


Nick_Naylor

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Re: The 2015 melting season
« Reply #3188 on: August 08, 2015, 10:54:56 PM »
AzSz88, Nick,

I have a graphics programme that can stack and in which I can change opacity, but that's not the same as averaging.


It gives you an average of the R, G and B channels, assuming you're working in RGB.
What do you mean by "average" if not that - understanding that no image program will understand the meaning of the colors?

ChrisReynolds

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Re: The 2015 melting season
« Reply #3189 on: August 08, 2015, 11:09:51 PM »
Nick,

Well the native format of NSIDC concentration is 0 to 255, IIRC, you can put the data in a bitmap. Indeed the Cryosphere Today regions image is just the NSIDC 25km grid with areas on it. To make the base mask for the PIOMAS grid I used for conversion to the PIOMAS grid.

I see what you mean about the layers approach, in theory four layers at 0.25 should be an average, I wasn' t really thinking about it. In a mono image, to which the white shade Bremen plots should convert, the resultant shade should indeed be the average. I may have a play around with it tomorrow.

jdallen

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Re: The 2015 melting season
« Reply #3190 on: August 08, 2015, 11:23:32 PM »
Ok folks, just spent a little time watching Climate Reanalyzer for a bit, and ended up with my hair standing on end.

The forecast has a *continuous* flow of moisture and energy (remnants of recent typhoons) streaming up along the East Asian coast, running into the RRR off of the Gulf of Alaska and getting flung north across the Bering and Eastern Siberia into the Chukchi and ESS.

But that's not the worst of it.  Check out this about 6 days out.  The weather leading up to it isn't particularly heartening either, as small cyclones of varying intensity are scuttling all over the pacific side of the Arctic.

I know it's not the same intensity, but... GAC 2015, anyone?
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Nick_Naylor

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Re: The 2015 melting season
« Reply #3191 on: August 08, 2015, 11:29:42 PM »
Chris, possibly some programs would give an average if you set 25% for each of the four layers, but it works differently for sure in Photoshop.
You'd need the top layer = 25%, the next one = 33%, the next = 50% and the bottom = 100%. Try both ways and check the RGB values.

plinius

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Re: The 2015 melting season
« Reply #3192 on: August 08, 2015, 11:30:55 PM »
quite good weather for the ice - a mild cyclone essentially insulating the whole icecap from warm & moist august air masses.

Bruce Steele

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Re: The 2015 melting season
« Reply #3193 on: August 08, 2015, 11:36:12 PM »
Paul Beckwith,  I had a couple posts # 2408+2410 upthread re. North Pacific warm water putting lots of heat into the Arctic. I make the argument that it is not directly sending that heat past the Bering Strait via water currents.

  Steele et al 2010 ( not me )showed that 80% of the ocean heating in the Pacific Arctic north of Alaska is from ocean heat flux, and only 20% due to ocean lateral heat flux( e.g. Bering Sea inflow), which mostly occurs within a few hundred kilometers from the coast. Moreover, the movement of Pacific Water from the Aleutian Passes to BeringStrait takes more than one year.  So pacific water is exposed to winter sea ice during it's voyage and loses it's heat.
« Last Edit: August 08, 2015, 11:43:13 PM by Bruce Steele »

jdallen

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Re: The 2015 melting season
« Reply #3194 on: August 08, 2015, 11:39:21 PM »
quite good weather for the ice - a mild cyclone essentially insulating the whole icecap from warm & moist august air masses.
Actually, plinius, it's *dragging* moisture and heat into the arctic with it.  I recommend watching the sequence in CA.  Watch in particular the flow through the Bering and across the eastern tip of Siberia.

In a similar vein, some shots of surface wind speeds at 24 hour intervals, starting 4 days out.  I'm not sure we can consider this particularly "friendly" to the pack, as torn up as it already is.
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jdallen

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Re: The 2015 melting season
« Reply #3195 on: August 08, 2015, 11:49:04 PM »
One last screen capture from CA - very speculative, it being a week out - but dramatic.  Massive plume of moisture from a typhoon remnant.

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Rubikscube

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Re: The 2015 melting season
« Reply #3196 on: August 09, 2015, 12:21:07 AM »
What do people think of this?
I saw the maps for Aug. 7, 2015 and 2012, and I thought they look very different, so I made this graphic to show what I mean.
Am I imagining it? With at least a month to go, will this make a difference in the final outcome?
If the melt season extends longer and warmer, which I think it will due to global record heat being set all over the place, can these weaknesses amalgamate and cause a break up of the ice sheet into 3 or 4 big parts?

I think the resemblance between 2012 and 2015 is striking, the pack will look very much like 2012 at minimum I imagine, only larger. Not sure whether the areas labeled "thin" really are that much thinner though. The pack won't break up into 3-4 big parts, but this season in general has been marred by unusually large attachments from the main pack and a long total ice edge, this latest one in Beaufort and Chukchi is rather unprecedented and very fascinating to watch.

Slow wing, I much appreciate the daily uni-bremen update of yours, keep it coming please. Adding some fade definitely makes it better though.

greatdying2

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Re: The 2015 melting season
« Reply #3197 on: August 09, 2015, 01:37:57 AM »
Fourth lowest according to this NSIDC graph.
The Permian–Triassic extinction event, a.k.a. the Great Dying, occurred about 250 million years ago and is the most severe known extinction event. Up to 96% of all marine species and 70% of terrestrial vertebrate species became extinct; it is also the only known mass extinction of insects.

slow wing

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Re: The 2015 melting season
« Reply #3198 on: August 09, 2015, 04:05:48 AM »
U. Bremen update now with cross-fade between frames, as requested.

Not sure how much of the difference from yesterday is just peek-a-boo ice and fluctuations. But, for the first time this season if I recall correctly, the Atlantic side is showing a drop in concentration over a wide front and that extends all the way in to around 5 degrees from the Pole.

Still only yellows and oranges but who knows if it is the start of something? Others have posted evidence of warm water encroaching under the Atlantic side of the ice pack.

The uncertainty of it all is illustrated for me by this melt season's history in the Beaufort Sea as just posted by Jim Hunt:
http://forum.arctic-sea-ice.net/index.php/topic,1149.msg59966.html#msg59966
There the ice concentration collapses region by region and without any evident warning.

Is it too late for something similar on the Atlantic side?

Click on gif to see the all-new cross-fade between yesterday's and today's maps:
(EDIT: the cross-fade didn't work when posted, so have swapped in the format without cross-fade.)

« Last Edit: August 09, 2015, 01:51:49 PM by slow wing »

greatdying2

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Re: The 2015 melting season
« Reply #3199 on: August 09, 2015, 04:09:53 AM »
Click on gif to see the all-new cross-fade between yesterday's and today's maps:
Thanks. But cross-fade isn't working (for me at least).
The Permian–Triassic extinction event, a.k.a. the Great Dying, occurred about 250 million years ago and is the most severe known extinction event. Up to 96% of all marine species and 70% of terrestrial vertebrate species became extinct; it is also the only known mass extinction of insects.