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binntho

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Re: The 2018 melting season
« Reply #3050 on: August 24, 2018, 07:46:18 AM »
Where the -11 comes from is that in Wayne Davidson's home town, the conditions are such that in an average year, the temperature is roughly -11 degrees by the time the ice starts to form.  No more.  This forum shouldn't be treating it as a magic number.

Thanks for clearing that up!
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mostly_lurking

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Re: The 2018 melting season
« Reply #3051 on: August 24, 2018, 08:18:13 AM »
here is the 1st part if you want:

<snip, no, thanks. I've only watched 2 minutes, but I'm pretty sure it will only get worse in sophistry from then on. Don't post this stuff anymore, or you're out of here; N.>

« Last Edit: August 24, 2018, 06:47:15 PM by Neven »

oren

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Re: The 2018 melting season
« Reply #3052 on: August 24, 2018, 08:29:21 AM »
August 19-23.
The surviving Beaufort blob has started moving east. If it continues moving it will disappear in no time, as the open water is warmer and more saline. In fact it seems the whole Pacific-side front has moved eastwards in the last couple of days. On the Atlantic side a new bulge has appeared, hinting at renewed export movement and hurting extent losses.

gerontocrat

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Re: The 2018 melting season
« Reply #3053 on: August 24, 2018, 09:34:52 AM »
..snip
The speaker talks about facts, but he didn't bring any. It may be that an extra strong flash of solar outburst may have a small and short-lived influence on earth's temperature. But I completely miss the development of the changes in quantitative numbers over the last 140 years.
He takes all the info from mulipule papers that I think he puts up on the 1st part of the video.
Although to see those papers you would have to watch another video and look at stuff he puts out. He isn't the standard "denier" but I do understand why you would put him in that category. Thanks for replying.      I know what potholer thinks about him :)

What on earth has the the history of sunspots over 140 years got to do with the 2018 Melting Season ? Somewhere on this forum I presume there are threads about the climate?
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johnm33

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Re: The 2018 melting season
« Reply #3054 on: August 24, 2018, 09:46:01 AM »

mostly_lurking

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Re: The 2018 melting season
« Reply #3055 on: August 24, 2018, 10:16:54 AM »
What on earth has the the history of sunspots over 140 years got to do with the 2018 Melting Season ? Somewhere on this forum I presume there are threads about the climate?

Sorry, things got sidetracked like they sometimes do .. feel free to delete or move.

uniquorn

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Re: The 2018 melting season
« Reply #3056 on: August 24, 2018, 10:51:51 AM »
Today's ecmwf wave and temps from windy.

Thawing Thunder

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Re: The 2018 melting season
« Reply #3057 on: August 24, 2018, 11:22:12 AM »
At least for waves, the ESS arm is finally waning.
The Thunder was father of the first people, and the Moon was the first mother. But Maxa'xâk, the evil horned serpent, destroyed the Water Keeper Spirit and loosed the waters upon the Earth and the first people were no more.

uniquorn

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Re: The 2018 melting season
« Reply #3058 on: August 24, 2018, 11:55:33 AM »
The forecast is for higher waves next week.

Looking for reasons for the Lincoln Sea melt, here is mercator 34m salinity, jun2017-aug2018, every 8th day and a bathymetry map

gerontocrat

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Re: The 2018 melting season
« Reply #3059 on: August 24, 2018, 12:02:31 PM »
What on earth has the the history of sunspots over 140 years got to do with the 2018 Melting Season ? Somewhere on this forum I presume there are threads about the climate?

Sorry, things got sidetracked like they sometimes do .. feel free to delete or move.
Sorry for being so irritated. This sunspot thing keeps on popping up all over the place. It's a distraction (another common ploy often used by deniers) from the main subject at issue.

ps: "governor" is only a courtesy title granted by the computer program that runs this forum. Like you, the only posts I can move, delete or modify are my own.
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binntho

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Re: The 2018 melting season
« Reply #3060 on: August 24, 2018, 12:36:53 PM »
Waynes -11c/-1.8c post

Quote
... there is an apparent thermal balance,  where [...]  colder than -11 C  surface air seems imperative for sea ice to form
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

binntho

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Re: The 2018 melting season
« Reply #3061 on: August 24, 2018, 12:43:35 PM »
The forecast is for higher waves next week.

Looking for reasons for the Lincoln Sea melt, here is mercator 34m salinity, jun2017-aug2018, every 8th day and a bathymetry map

There seem to be a lot of salt-water intrusions, which I presume indicate warm surface water currents. Not that I'm sure how much trust to put in such maps, but a couple of things stand out:

  • The significant pulse of salt water moving west along the north coast of Greenland and down the Nares strait
  • The strong current stretching east through the Laptev to the edge of the ESS where it seems to disappear
  • The influx of salt water throught the Bering strait, meeting the above mentioned current in the ESS
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

Pmt111500

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Re: The 2018 melting season
« Reply #3062 on: August 24, 2018, 01:07:41 PM »
The forecast is for higher waves next week.

Looking for reasons for the Lincoln Sea melt, here is mercator 34m salinity, jun2017-aug2018, every 8th day and a bathymetry map

One salinity pulse over Greenlands northern tip. Could also be among the first ones. I've not followed Mercator salinity now for some three years so could have happened. Other wise it looks like atlantic and pacific salts are 50:50 what Arctic basin gets.
« Last Edit: August 24, 2018, 01:15:42 PM by Pmt111500 »

uniquorn

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Re: The 2018 melting season
« Reply #3063 on: August 24, 2018, 03:21:29 PM »
I was thinking more of the steady flow of higher salinity/warmer water along the Lomonosov ridge area which has to surface when it meets Greenland.
Accepted that it is only a model.

Edit: A slower build up over years. Maybe the 92m salinity, jun2017-aug2018 is less distracting. (2.3MB)
Mercator Ocean https://tinyurl.com/ydzcgdel
« Last Edit: August 24, 2018, 04:10:33 PM by uniquorn »

Pmt111500

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Re: The 2018 melting season
« Reply #3064 on: August 24, 2018, 04:12:55 PM »
I was thinking more of the steady flow of higher salinity/warmer water along the Lomonosov ridge area which has to surface when it meets Greenland.
Accepted that it is only a model.

Edit: A slower build up over years. Maybe the 92m salinity, jun2017-aug2018 is less distracting. (2.3MB)

Ah ok, and that looks indeed like the salinity reaches Nares regularly . The Actic could be said to have Atlantified all the way to Lomonosov then?

Tor Bejnar

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Re: The 2018 melting season
« Reply #3065 on: August 24, 2018, 04:26:36 PM »
The salinity maps make is 'obvious' why some consider the Arctic to be estuarine in nature.  With SLR, many an estuary becomes more salty (IIRC).  I know there is much more than that one influence, but 'seawater intrusion' sure influences what happens with ice (speeds melting and inhibits freezing). 
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

FrostKing70

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Re: The 2018 melting season
« Reply #3066 on: August 24, 2018, 08:16:01 PM »
Very interesting!   

Does anyone know of any models which predict what the increased salinity would do to the freeze and melt each year?   Intuitively, it seems that as we have less ice to melt each year, the resulting fresh & salt water mixture would take longer to freeze, which would in turn result in less ice to melt the following year (another feedback mechanism / tipping point?).

FishOutofWater

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Re: The 2018 melting season
« Reply #3067 on: August 24, 2018, 09:40:58 PM »
It would be most interesting to focus in on the salinity from the Nares to the Fram on the north coast of Greenland. There are multiple coastal currents that move in the opposite direction of the main flow direction in the offshore regions. The loss of landfast ice around Greenland and the northern CAA may be increasing Ekman upwelling. This process will expedite the opening of the CAA channels and open the flood gates to fresh water flow through the CAA.

There is still a huge input of fresh water from Siberian rivers so the Arctic ocean will not quickly lose its fresh water lid, but this will lead to a strong reduction in fresh water in years when the AO is positive.

Here's a link to a pretty good video about Eckman transport. It's worth watching to understand what's happening in the Nares strait and on the north coast of Greenland.

uniquorn

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Re: The 2018 melting season
« Reply #3068 on: August 25, 2018, 12:06:27 AM »
Thanks FOoW, that suggests a more local reason for what we are seeing. I followed up the vid with http://www.earth.ox.ac.uk/~helenj/planetearthHT12/Lecture7.pdf
your first link gave me a bit of a shock;)

johnm33

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Re: The 2018 melting season
« Reply #3069 on: August 25, 2018, 01:34:28 AM »
Thats a stunning animation uniquorn, it shows Amundsen driving the gyre, Atlantic water flowing in through St.Anna trough driving over to Lomonosov and circling back towards Nares, probably the source of the deep current that flows into Petermann. There's also a strange line appears pointing towards Sverdrup Is. on 09:28 possibly the previous too, followed by a rapid transition and recovery of the salinity in north Barents.  I'm wondering if different dates would show a tidal signature.



[spelling]
« Last Edit: August 25, 2018, 10:09:41 AM by johnm33 »

wallen

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Re: The 2018 melting season
« Reply #3070 on: August 25, 2018, 02:36:39 AM »
Looking at this, it looks as if there maybe be a linking of the salinity flow from the Pacific and that form the Atlantic it time to come. Wondering what impact that may have?

The forecast is for higher waves next week.

Looking for reasons for the Lincoln Sea melt, here is mercator 34m salinity, jun2017-aug2018, every 8th day and a bathymetry map

litesong

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Re: The 2018 melting season
« Reply #3071 on: August 25, 2018, 03:29:45 AM »
Updating a previous post:
The sun is less than 12arcdeg above the horizon at the North Pole (& decreasing by over one third arcdeg per day), almost 12 arcdegs LESS than at summer beginning.
Update to my update:
Already the sun is LESS than 11arcdegs above the horizon at the North Pole, over a solar diameter lower in the sky from my last report. Summa is rapidly proceding..... to its end.   

slow wing

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Re: The 2018 melting season
« Reply #3072 on: August 25, 2018, 06:01:00 AM »
U. Bremen's false colour ice concentration maps show a week's action in the Arctic basin, ending on the map just released, 2018-08-24...

uniquorn

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Re: The 2018 melting season
« Reply #3073 on: August 25, 2018, 01:52:12 PM »
<snippage>
The loss of landfast ice around Greenland and the northern CAA may be increasing Ekman upwelling.
<snippage>
I'm not convinced that Ekman transport explains what we are seeing in the Lincoln Sea. It may be a contributary factor but I'm not sure it is consistent with A-Teams animations of floe movement, changes of wind direction and the persistence of low concentration ice there.

Today's ecmwf waves and wind from windy and a side elevation of the arctic ocean. I didn't appreciate the height of the Lomonosov Ridge before
edit: not sure how up to date those water layers are
A closer look at the mercator salinity model at 0m-318m, jun-aug2018, every 3rd day. At 92m one of the coastal currents is compressed from the north. Surprisingly, no real increase in salinity is shown above at 34m but it does pop up at 0m.
Accepted that this is a model (7.8MB click to run)
« Last Edit: August 25, 2018, 04:51:21 PM by uniquorn »

FishOutofWater

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Re: The 2018 melting season
« Reply #3074 on: August 25, 2018, 04:33:23 PM »
<snippage>
The loss of landfast ice around Greenland and the northern CAA may be increasing Ekman upwelling.
<snippage>
I'm not convinced that Ekman transport explains what we are seeing in the Lincoln Sea. It may be a contributary factor but I'm not sure it is consistent with A-Teams animations of floe movement, changes of wind direction and the persistence of low concentration ice there.

Agreed that there's much more going on. I just read a paper that opened my eyes to some of the possibilities. I'm going to work on writing it up. Many things begin to happen as sea ice declines and they interact with each other. What's clear from A-Team's animations and your animations and Polarstern's data is that there's an increase in heat and salinity from the north coast of Greenland to the Lincoln sea to the CAA. I think I found one more clue why in the paper I just read.

Ned W

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Re: The 2018 melting season
« Reply #3075 on: August 25, 2018, 11:30:59 PM »
From the data thread...

That would be a fine analysis if you ignored the Battle of the Bulge on the Atlantic Front.

Battle of the Bulge ... I like it. 

slow wing

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Re: The 2018 melting season
« Reply #3076 on: August 26, 2018, 05:11:51 AM »
U. Bremen's false colour ice concentration maps show a week's action in the Arctic basin, ending on the map just released, 2018-08-25...

slow wing

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Re: The 2018 melting season
« Reply #3077 on: August 26, 2018, 05:24:34 AM »
Today, Aug 25, is one of the dates shown on Neven's year-to-year ice concentration map comparison.

It's easy to forget that, for the most recent two previous years, 2016 and 2017, the ice on this date was in bad shape for close to the North Pole and on the Russian side.

This year, 2018, the ice is compact on the Atlantic side but spread out on the Pacific side. Low atmospheric pressure is expected to begin to dominate within the next day or so, bringing some moderately strong winds. How much of the Pacific-side ice debris will that clean up?

Aluminium

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Re: The 2018 melting season
« Reply #3078 on: August 26, 2018, 08:54:22 AM »
August 21-25.

oren

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Re: The 2018 melting season
« Reply #3079 on: August 26, 2018, 09:08:18 AM »
It's easy to forget that, for the most recent two previous years, 2016 and 2017, the ice on this date was in bad shape for close to the North Pole and on the Russian side.
Thanks for this reminder. 2016 was a total mess near the pole, and in terms of a hypothetic index of latitude-weighted ice area or difficulty-weighted ice area, IMHO was lower than even 2012.
OTOH, this also made it vulnerable to early refreeze.

Tech note: the melting-difficulty weighted ice area index would calculate the average concentration of a given grid cell on September 5th-20th, and calculate weights for each cell based on its resistance to concentration loss. The higher the September concentration, the higher the weight. The index then sums current ice area on a given date, weighted by these weights. So a year that loses ice early in the CAB but delays Hudson and Baffin will show these losses much more clearly with this index.
Around the September minimum, the index will show how far the season was from a BOE, in terms of required additional energy/melting punch.

Jim Hunt

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Re: The 2018 melting season
« Reply #3080 on: August 26, 2018, 10:30:13 AM »
Meanwhile where the "oldest, thickest" sea ice in the Arctic allegedly remains Polarstern has headed back to the Greenland Sea as the waters north of Greenland starts to refreeze:

http://GreatWhiteCon.info/2018/08/could-northabout-circumnavigate-greenland-in-2018/#Aug-26

Thanks to a heads up from Treform2 there comes evidence that on the other side of the Lincoln Sea the last remnants of the Ward Hunt Ice Shelf are disintegrating:
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diablobanquisa

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Re: The 2018 melting season
« Reply #3081 on: August 26, 2018, 11:53:29 AM »
Sorry, but I can't see the disintegration of the last remnants of the Ward Hunt Ice Shelf.
I just see sea ice drifting from the north, and maybe some refreeze.

Aug 15th

Aug 20th

Aug 23rd

Aug 24rd

Am I missing something?

Jim Hunt

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Re: The 2018 melting season
« Reply #3082 on: August 26, 2018, 01:26:54 PM »
Sorry, but I can't see the disintegration of the last remnants of the Ward Hunt Ice Shelf.
I just see sea ice drifting from the north, and maybe some refreeze.

Perhaps it's not very strong evidence?

However it certainly looks to be in several pieces on all of your SAR visualisations.
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uniquorn

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Re: The 2018 melting season
« Reply #3083 on: August 26, 2018, 01:48:26 PM »
Today's ecmwf wave and temps from windy. Stronger warm winds and waves are forecast north of SZ over the next few days moving east over the Laptev sea.

edit:crash course in salinity/temp/density - https://www.colorado.edu/geography/class_homepages/geog_4271_f12/lectures/notes_6.pdf
« Last Edit: August 26, 2018, 03:17:26 PM by uniquorn »

Neven

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Re: The 2018 melting season
« Reply #3084 on: August 26, 2018, 02:30:16 PM »
Sorry, but I can't see the disintegration of the last remnants of the Ward Hunt Ice Shelf.
I just see sea ice drifting from the north, and maybe some refreeze.

Some additional info from 7 years ago. If true, this is a 'nice' addendum to all the articles about the open water event north of Greenland.

Remember, the disintegration of these shelves is what convinced climate risk denier heroine Judith Curry that current Arctic sea ice loss is caused by human activities.
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Jim Hunt

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Re: The 2018 melting season
« Reply #3085 on: August 26, 2018, 02:55:04 PM »
Some additional info from 7 years ago. If true, this is a 'nice' addendum to all the articles about the open water event north of Greenland.

I rather like the sound of Espen's "Costa del Hunt"!

Some more evidence from NASA on August 22nd 2002:

"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

mostly_lurking

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Re: The 2018 melting season
« Reply #3086 on: August 26, 2018, 03:09:30 PM »
....snip

Remember, the disintegration of these shelves is what convinced climate risk denier heroine Judith Curry that current Arctic sea ice loss is caused by human activities.
I don't know....where did she say that? I frequent her stuff quite often and don't see where she has changed her position. This is from her last "debate":

https://curryja.files.wordpress.com/2018/06/debate1.pdf


echoughton

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Re: The 2018 melting season
« Reply #3087 on: August 26, 2018, 03:12:17 PM »
....snip

Remember, the disintegration of these shelves is what convinced climate risk denier heroine Judith Curry that current Arctic sea ice loss is caused by human activities.
I don't know....where did she say that? I frequent her stuff quite often and don't see where she has changed her position. This is from her last "debate":

https://curryja.files.wordpress.com/2018/06/debate1.pdf

Yes, don't know why Neven felt the need to insert Judy here. She has been on board with human caused CC for a long time. She and others simply don't go in for the "shock and awe" wing of the debate.



mostly_lurking

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Re: The 2018 melting season
« Reply #3088 on: August 26, 2018, 03:13:26 PM »
....snip

Remember, the disintegration of these shelves is what convinced climate risk denier heroine Judith Curry that current Arctic sea ice loss is caused by human activities.
I don't know....where did she say that? I frequent her stuff quite often and don't see where she has changed her position. This is from her last "debate":

https://curryja.files.wordpress.com/2018/06/debate1.pdf

Yes, don't know why Neven felt the need to insert Judy here. She has been on board with human caused CC for a long time. She and others simply don't go in for the "shock and awe" wing of the debate.



Well, her presentation said this :

"JC’s   response:    Man-made   CO2   emissions   
are   as   likely   as   not   to   contribute   less   than   
50%   of   the   recent   warming   "

So kind of middle of the road.

echoughton

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Re: The 2018 melting season
« Reply #3089 on: August 26, 2018, 03:33:13 PM »
And the point Neven was making was regarding the disintegration of that particular ice sheet. Multi-year ice has been falling for sure, and I am NOT minimizing a section of ice that was thought to be some of the thickest up there...going poof!. But the CAB is completely filled with multi-year ice, is it not? T

NeilT

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Re: The 2018 melting season
« Reply #3090 on: August 26, 2018, 03:41:13 PM »
So kind of middle of the road.

It takes a long time to row back from the position she took.  Condemning the study she was heavily involved in when the study leader had to admit that there was no evidence that climate temp measurements had been tampered with or were misleading.

That was a pretty clear break with reason.

The problem is that, as time rolls on, there isn't really a high point to cherry pick any more.  The high's just keep getting higher.

So if it takes disintegrating ice shelves, then so be it.

I thought all the CAB facing ice shelves had been starting to break up for at least a decade and a half now.  Not consistently but more like the Antarctic.
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NeilT

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Re: The 2018 melting season
« Reply #3091 on: August 26, 2018, 03:45:25 PM »
Looking at NSIDC Chartic today, 2018 is now just poking above 2015.  Also 2015 went into some more accelerated melt for the next week.

So, unless the ESS melts out completely in the next week or two, it's looking like 2018 will finish, on extent, in 6th place.
Being right too soon is socially unacceptable.

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Re: The 2018 melting season
« Reply #3092 on: August 26, 2018, 04:51:19 PM »
melting-difficulty weighted ice area index

That's a great idea. The forum and commonly-used metrics have always struggled with the fact that all ice is not created equal (Hudson Bay or already exported out the Fram vs. Lincoln Sea or the pole). Basin-specific charts by Wipneus et. al. do address it to a degree, but this idea gets right to the point.

uniquorn

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Re: The 2018 melting season
« Reply #3093 on: August 26, 2018, 05:14:43 PM »
Air turbulence again over the Svalbard 'hotspot'. Worldview terra/modis with brightness temperature band15, day and night, aug26.
light blue ~0C
bright yellow ~5C
https://tinyurl.com/y8goe2et

diablobanquisa

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Re: The 2018 melting season
« Reply #3094 on: August 26, 2018, 08:29:21 PM »
Thanks to a heads up from Treform2 there comes evidence that on the other side of the Lincoln Sea the last remnants of the Ward Hunt Ice Shelf are disintegrating:

Ward Hunt Ice Shelf on Ellsemere Island has collapsed in last few days


Sorry, but I can't see the disintegration of the last remnants of the Ward Hunt Ice Shelf.
I just see sea ice drifting from the north, and maybe some refreeze.

Perhaps it's not very strong evidence?

However it certainly looks to be in several pieces on all of your SAR visualisations.

I think that on the SAR images  it looks like usual since 2015, I can't see a collapse or further major disintegration during the last few days.

And MODIS 2015 vs. 2018


« Last Edit: August 26, 2018, 11:02:57 PM by diablobanquisa »

diablobanquisa

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Re: The 2018 melting season
« Reply #3095 on: August 26, 2018, 08:30:18 PM »

Some additional info from 7 years ago.

Thank you, Neven! In addition, a nice animation that summarizes the disintegration of the Ellesmere Island Ice Shelves from 1906 until 2015 can be found here: https://wirl.carleton.ca/research/ice/ice-shelves/ice-shelf-extents/

Great information about the 2011 calving event is also available there: https://wirl.carleton.ca/research/ice/ice-shelves/calving-2011/


FishOutofWater

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Re: The 2018 melting season
« Reply #3096 on: August 26, 2018, 09:22:05 PM »
Over a month ago, when July turned cold and stormy I noted that 2018 is closest weatherwise to 2015 and may well be closest in September ice extent.

Over a year ago I wrote a story on Dailykos that the oldest and thickest ice around the north coasts of Greenland and the CAA was breaking off and heading south. Of course, this didn't start last year or this year as the video of the 100 year old record of ice shelves on Ellesmere Island illustrates. All the changes in the Arctic that we're seeing today have been in the making for a long time.

As the ice shelves and landfast ice retreats the potential for both upwelling and downwelling along the continental shelf margins increases and these changes may affect currents in the Arctic and north Atlantic. The shifting distribution of ocean heat shifts the release of heat to the atmosphere and that impacts storm tracks and the jet stream.

In terms of area and extent this summer's melt season is pretty boring. in terms of what's happening on the Atlantic side and the north coast of Greenland and the CAA it's very interesting. Warm, salty Atlantic water continues its advance into the Arctic with a significant increase in salinity in the channels of the CAA and along the north coast of Greenland over the past 2 years. Unfortunately, Mercator ocean does not have continuity for more than about 16 months because they made major updates to their models. I have been viewing Mercator Ocean for many years, but memory is a poor tool for scientific analysis. I note that I forgotten how bad the ice looked on this date in 2016.

Greenbelt

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Re: The 2018 melting season
« Reply #3097 on: August 26, 2018, 11:15:21 PM »
Here we go again with the weather forecast.

The last big storm predicted in (some of) the model forecasting didn't verify. However, the prediction of stormy weather and windy conditions spanning much of the central Arctic seems fairly robust. I will be interested to see if the wind and waves finally dissipate the fragile looking ice throughout the ESS and toward the Beaufort.

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Re: The 2018 melting season
« Reply #3098 on: August 26, 2018, 11:27:05 PM »
I think that on the SAR images  it looks like usual since 2015, I can't see a collapse or further major disintegration during the last few days.

I can't see the "cracks" on this 2016 SAR image courtesy of Nukefix?

It is better quality than the Polarview renderings above though.
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diablobanquisa

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Re: The 2018 melting season
« Reply #3099 on: August 27, 2018, 12:42:22 AM »
I think that on the SAR images  it looks like usual since 2015, I can't see a collapse or further major disintegration during the last few days.

I can't see the "cracks" on this 2016 SAR image courtesy of Nukefix?

It is better quality than the Polarview renderings above though.

I'm sorry Jim, but I really don't understand which are the new "cracks" you are referring to.

Anyway, if it is true that in the last few days the last remnants of the WH ice shelf have fractured, collapsed and are disintegrating right now, I'll just wait for the official reports about this major event.



(attached SAR images: Aug 20 and 24 ; MODIS: Aug 20)
« Last Edit: August 27, 2018, 12:50:50 AM by diablobanquisa »