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werther

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This melt seasons analysis
« on: August 27, 2013, 11:42:10 AM »
A first, very crude, attempt to analyse this strange year.

And a rather long tale, I fear...)

I compared high concentration (UB +90%)/low concentration area 2013 to 2012 for 26 August.
On high concentration: ’12 had 2,1 mkm2 against ’13 2,7 mkm2 (Note: ’13 also has 0,7 mkm2 HC ice on the far Siberian side of the CAB. I’ll get to that later…). This is the core of the sea ice cover, in which the remaining “mesh-pack” is embedded. After checking my CAD work, I see not much difference in the area covered by the “mesh pack” in both years, about 1,1 mkm2, although the regional spread of it has changed considerably.
On the low concentration side, ’12 had 0,9 mkm2 against 2,0 mkm2 for ’13 (including the 0,7 mkm2 Siberian side HC swath).

The important difference in ‘13 is the 0,6 mkm2 larger HC area in the core. This difference is located on the Beaufort side of the CAB. It fits well with the area that’s been about an average of 3 dC colder during the May-August period than last year.
The most poignant difference is the 1,1 mkm2 larger LC area stretching way into the ESAS. That part of the Arctic was colder than last year, but much less pronounced than near the CAA, about 0,5dC.

The only stretch with less ice than last year is the Atlantic side. Dismissing the bunch of stubborn fast ice SW of Severnaya Zemlya in the Kara Sea, the difference is 250K, partly in the EGS, most in the Barentsz sector of the CAB. That fits with the vast area of +2dC warmer temps than last year over the Barentsz and Norwegian Seas.

What happened? The mobility of the pack in winter pushed vast parts of the “mesh pack” into the Beaufort sector. Likewise, the remaining HC ice of ’12 in the Laptev sector (the’Goat’s Head, FI) rotated back into the Greenland sector, while the Fram express never really picked up except for first- and second year ice that was over the Nansen Basin late winter/spring.
In the same rotation, some second- and good new FYI headed for the ESAS sector.

In a way, the reorganisation at work in the atmosphere over the Northern Hemisphere helped to set up a circulation that kept ice within the CAB and suppressed summer warming. A strong, persistent low over the American CAB side kept winds defending against much warming from the South. It is a feature related to the reorganisation I mentioned, as it went all the way up to the stratosphere. All Geopotential levels were anomalously low this summer over a tight area. This created it’s own Jet on 200Mb, while the Polar Jet, normally located over 55dN, almost faded out.
On the sideline, in summer the Jet usually is less strong than during winter. But this summer really stands out.

Based on the pattern, crudely described above, I see what happened not as a statistical ‘revert’ to normal, or rebound or whatever you can call the ups-and-downs in a range. I see this as a stage in a dynamical whirl of change. I think it is important to approach what’s going on like that. Whether the statistical or dynamical approach is taken, the short term effects are more or less the same. We see a possible range of ‘long-tail’ years rising. If so, it may be time to express some reconciliation to the pro’s and modellers. It is very possible the state of Arctic sea ice and the trend in GHG forcing will be more in line. At least, for some years.

That ASI won’t be an immediate “canary-in-the-coalmine” doesn’t mean the whirl of change will be less severe in other parts of our World.

In a way, that’s a pity. ASI is a clear feature to show what AGW is doing. Other events will be less concentrated and eyecatching, so much easier to deny any interrelation.

I tend to get to a new forecast. I do think this new pattern will regularly return in the coming few years. Maybe the winters might get less severe, thus still affecting the inevitable demise of the sea ice. I don’t think the reorganisation of NH atmospheric circulation is solely dependent on the state of the sea ice. There are more processes at work. A new stage will be met as soon as the stored heat in deeper ocean layers start to manifest consequences.
At some point, an anomalous sort of ENSO event will rise, and among other regions Antarctica may well be the place to look for new action. After all, it has been a bit quiet over there… (right, AbruptSLR?)

A last word on the high concentration swath on the Siberian side… When MODIS is studied, it is obvious that the properties of it’s ice are much different from the core pack. It is loose and thin. It is one of the reasons I think a qualitative interpretation should be added to the raw numbers come this year’s minimum.
The state of ASI isn’t going to get better, even though there now are obvious processes to promote a long tail… hat tip to Chris Reynolds, who supposed that even before this summer arrived.

Does it mean pro’s like Maslowski or Wadhams have it all wrong?

No. A first ice-free Arctic (less than 1 mkm2 remaining sea ice) at minimum is possible any year under the right conditions. But there’s evidence now in the real World how this will fit in a “long tail”.

werther

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Re: This melt seasons analysis
« Reply #1 on: August 27, 2013, 01:35:04 PM »
PS don't dig into the numbers I used to compare too deep. I haven't yet used my well-scaled CAD format yet, so it is a first relative comparison.

slow wing

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Re: This melt seasons analysis
« Reply #2 on: August 27, 2013, 02:38:36 PM »
Thanks, Werther. Very interesting introduction to the discussion.

So you are saying that this year has been dynamically very different to all recent previous years and that you expect this to continue in future years?

This may be true. But do we know for sure that it will be? What drives the new dynamics? And why didn't it appear in any of the years 2007-2012 in particular, when ice coverage wasn't so different?

Because it didn't appear in any of those years, I would suspect at least an element of fluctuation this year. However, I don't feel I understand the dynamics myself.

  As an initial hypothesis, I have been wondering if the presence this year of all those leads and that open water within the ice pack has let to greater thermal exchange and moisture exchange than in any of years 2007-2012, thus promoting cooler and cloudier weather. Just a hypothesis - further evidence would be needed to support or else discredit it.

Does that hypothesis make any sense to you? And how does it mesh with the dynamical explanation you have given above, if at all?

I will be interested to read the comments from those with greater experience and understanding than myself...


werther

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Re: This melt seasons analysis
« Reply #3 on: August 27, 2013, 03:41:09 PM »
Hi Slow Wing,

I used the term 'dynamical' to express the difference with 'statistical' on the general process of climate change under GHG forcing. I could theorize way out on this. Short, while writing I mixed the detail process of sea ice demise and the general pattern of AGW. That doesn't make the piece clearer...
In other words, the accelerating impact of AGW is the background for the process of sea ice demise. Because the background is 'dynamically' changing, it is impossible to refer to past patterns in yearly sea ice melt. Or, at least, that background should be kept in mind while analysing and surveying the future scenario's.

The driver of this year's or 'new' pattern is, IMO not just sea ice cover. It is  a mélange of different properties of the atmosphere/ocean system, FI snow cover, SSW's, the ITCZ, SST-patterns related to the TTC etc.
In my theory, it didn't appear before because it doesn't solely depend on sea ice cover. The mix is a stage in the global effects of AGW.
What I've come to understand in a lot of natural processes is that they are not proceeding together in a nice, linear range. It is much more like a matrix in time and space.

I think you're right to suppose an effect through all dispersed open water in the pack. It helped the 2m temps to stay cool and moist. Others could better elaborate on the 'dew-point' side of that, I'm not that good at that specific part of meteorology.
That said, I don't think it was the main reason for the Arctic Basin to stay cool this year. And it won't stave off further decline. But yes, I do think it is part of a negative feedback that may ensure a 'long tail' for sea ice survival until the Arctic Ocean is completely ice-free in summer.

helorime

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Re: This melt seasons analysis
« Reply #4 on: August 27, 2013, 03:47:09 PM »
I would hazard to guess that the broken up ice will be with us repeatedly and that in the right summer weather conditions there will be catastrophic melting.  Other than that I would not expect consistent patterns just based on this one year.  The rule of climate these days appears to be more variability.
Any sufficiently advanced technology is indistinguishable from magic.

ChrisReynolds

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Re: This melt seasons analysis
« Reply #5 on: August 27, 2013, 07:03:53 PM »
Werther,

I think we disagree actually. I don't think this year tells us anything about the possibility of a 'long tail'. From my understanding it doesn't change much with regards the possibility of a fast crash, that could still be what we see in the coming years. It's a reminder that weather is an active factor, from my efforts to understand what's going on in the atmosphere I see this year as likely to be a blip, a one off event.

werther

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Re: This melt seasons analysis
« Reply #6 on: August 27, 2013, 10:01:23 PM »
The disagreement is accepted, Chris.

I may well read too much from short term noise. Meanwhile I would hope for a thread where we can analyze this season as good as we can. I admit I’ve been triggered by some posts lately and may have overrated my insight.

It’s a damn lot of info and I’m worried that this year is going to fuel lots of denial. In that case, thanks for addressing it as a, likely, blip in advance.

ChrisReynolds

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Re: This melt seasons analysis
« Reply #7 on: August 27, 2013, 10:28:52 PM »
I could be wrong Werther,

There may be a reason to see the weather pattern of 2007 to 2012 as a blip, and 2013 as the start of a return to normal. I can't argue strongly that it's the other way round. Really it is little more than a hunch based on the various loose ends I have on this matter.

It is worth noting however that June/July losses in NSIDC and CT Area are high. For NSIDC 1989 to present losses over that period are the highest on record. For Ct Area 2013 is amongst the 5 largest June/July losses.

I'm avoiding commenting too much though, because I'm in the process of getting things in order for my upcoming blog posts.

ChrisReynolds

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Re: This melt seasons analysis
« Reply #8 on: September 02, 2013, 08:36:24 PM »
Werther,

Thanks for starting this thread, sorry to be a bit late, but as stated above I needed to get my thoughts and the data together. So if I can add my initial analysis of the 2013 melt season....
http://dosbat.blogspot.co.uk/2013/09/summer-2013.html

werther

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Re: This melt seasons analysis
« Reply #9 on: September 02, 2013, 09:48:45 PM »
Thanks, Chris,

I've been over your blog post a first time. I'll get back to it when I'll be doing my own graphics after minimum. I'm not that good at interpreting your numeric correlations and graphs. But I do have esteem for the conclusions you draw based on your method. They narrow the band for the wide range of guesswork that will fill the blogosphere straight after Minimum.
Thanks for arranging some credible stakes!

ChrisReynolds

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Re: This melt seasons analysis
« Reply #10 on: September 03, 2013, 08:21:43 PM »
Sorry, I am not always as clear and simple as I might be. If you have questions just ask here, I know the spam-catching at the blog can be a pain, although as owner it never seems to bother me.

Acts5v29

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Re: This melt seasons analysis
« Reply #11 on: September 04, 2013, 05:12:32 PM »
Good afternoon,

It might be worthwhile looking - not at the melt figures as per Arctic Sea-Ice Monitor - but at the differing concentration datewise year on year.

Note: I wrote to this website asking permission to use 3-5 of their Aug 22nd graphics to illustrate an article. They show the concentration of thick ice vacating the main arctic and accumulating away to the area north of Greenland. I have received no reply, but since writing this website now only shows data going back a single year (!)

Acts5v29

ChrisReynolds

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Re: This melt seasons analysis
« Reply #12 on: September 04, 2013, 06:29:13 PM »
Acts5v29,

The concentration data you link to is from a US Navy model, you're OK to use their images provided they are credited. However due to a change in the atmospheric data used to drive the ice/ocean parts of the model both thickness and concentration jumped up rapidly, this happened a couple of weeks ago. Those of us with a habit of collecting images were able to show the substantial change.

The best source for comparing satellite observed concentration data for 2012 and 2013 is Wipneus, see his 'home brew AMSR2 thread'.

werther

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Re: This melt seasons analysis
« Reply #13 on: September 05, 2013, 08:38:46 AM »
Analysing...

I wonder... now that NCEP/NCAR has all data in to compare the three summer months, could some more clues be found.
Haven't got much time now. But initially, SLP shows an anomalous doughnut of low pressure circlin' Greenland. With a tight minimum near the Pole. High anomalies encircle the doughnut, concentrated around 60dN Alaska and N. European Russia.

As this is also reflected on 500 and 250 Mb, it doesn't look just like a random spread. And it differs. Radically. From 2007. Sure. From the whole past 2007 range. And from the climo since 1979.
One thing speaks out loud (to me, at least...): if this summer was such an opposite against the high melt pattern years, the more it amazes how strong the melt still was.

Have to dig deeper. And have a look on the Antarctic side. How's winter turning out over there?

ChrisReynolds

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Re: This melt seasons analysis
« Reply #14 on: September 09, 2013, 10:09:14 PM »
Werther,

I've been musing along a slightly new line.



That's a plot of average geopotential height along 63.75 latitude, average summer GPH for the periods stated. There's a change in the most recent decade, but I need to download more data to get a grip on it.

The point is - look at the waves...

werther

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Re: This melt seasons analysis
« Reply #15 on: September 10, 2013, 09:07:16 AM »
Right... can't spend much time, nor is my head clear enough to test my wits... but, assuming you have the right hand bar on day of the year (why the .5's?), there's a good swing at sunset/start of winter. Seems plausible. So the swing is getting less pronounced then (at least, near the Polar Circle). Seems to fit with my last spring winter analysis of rising GPH levels...
Interesting approach, Chris.
I'll try to contribute (limited by work, family affairs (ill father) and general crisis survival mode).

pikaia

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Re: This melt seasons analysis
« Reply #16 on: September 10, 2013, 10:52:12 AM »
Right... can't spend much time, nor is my head clear enough to test my wits... but, assuming you have the right hand bar on day of the year ...
The scale is longitude, not day of the year! ("latitude 63.75, summer")

werther

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Re: This melt seasons analysis
« Reply #17 on: September 10, 2013, 01:16:53 PM »
OK Pikaia, the thought crossed my mind, but, as said, I'm not that witty. And the occupational therapy goes on... 63.75 x 280 (-80)... that would place Chris' pronounced wave over the Eastern tip of Southampton Island, Hudson Bay...

Vergent

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Re: This melt seasons analysis
« Reply #18 on: September 10, 2013, 01:57:43 PM »
Graphs without scales, are like girls without curls.

Vergent

ChrisReynolds

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Re: This melt seasons analysis
« Reply #19 on: September 10, 2013, 08:50:41 PM »
Sorry I thought it would be obvious, my bad.

The x axis (across) is geopotential height for 500mb and is obviously in metres above sea level. The y axis (up) is as Pikaia correctly asserts longitude.

The peak at about 225degE is north of the Rockies and seems to be a result of Jetstream steering around the north of the Rockies (I've read about their role in the jet somewhere before).

Between 270 and 245 there is a progression as time proceeds with the average summer GPH moving upwards Greenland is in the 300 to 340 degrees region.

But....

There is no matching change in the geopotential height pattern at this latitude over other parts of the globe, the region 270 to 245 is an 'odd-ball'.


Sorry to read about your father Werther - wish you the best.

SCYetti

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Re: This melt seasons analysis
« Reply #20 on: September 17, 2013, 11:52:23 PM »
Quote
Sorry to read about your father Werther - wish you the best.
Werther, I wasn't able to read anything of your father but I would like to echo the sentiment that "I wish you the best." My father died 22 years ago when I was 39 and I still miss him.

I agree with your melt season analysis and would like to add my inexpert view.

I live in South Carolina where the climate is hot and humid in the summer with mild winters. Yet our weather is usually said to come from elsewhere. We get tropical storms and hurricanes from the Caribbean and sometimes from the northeast coast of Africa. Most weather comes from the west. Sometimes bringing warmth and moisture from the Gulf of Mexico. Sometimes it brings cool air down from Canada. Thus when I read that the weather in the Arctic was unusually cold this summer I wondered where that came from. Of course it had to originate in the Arctic itself. The broken ice kept the Arctic water at about -2 C. The Arctic cyclones prevented the usual freshwater surface layer from developing by mixing the deeper salt water and the winter's ice having leached out much of its salt content could not melt at -2C.

Basically what happened in the Arctic stayed in the Arctic. Any cool Arctic breezes that might have cooled Alaska or Siberia would have had to have been offset by warm air blowing into the Arctic. With a diminishing jet stream this may be a new normal for a couple of years. In noting however how the Norwegian and Russian side of the ice pack continues to recede we must conclude AGW continues.

I would like to include the results of a little kitchen experiment I did. I prepared about a gallon of ice water, to have water at a consistent temperature. I placed 8 ounces of crushed ice in two identical 16 oz. cups. I mixed 16 oz. of my ice water with 1 tbs. salt to roughly simulate sea water.  I filled one cup with 8 oz (by weight)  ice and then the rest of the volume with ice cold tap water, 32F or 0C. The other cup I filled with the same 8 oz. ice and salt water also 32F. Shortly after, I measured the temperature of both. The plain water was 32F and the salt water was 29F. It took 2 and 1/2 hours for the plain ice water to melt completely. I weighed the ice remaining in the salt water and found it to be 1 oz. (My kitchen scales are only accurate to .2 oz.) I am suggesting something similar happened in the Arctic this year as to the preservation of so much ice.

While I sit back and await my Nobel prize  (there isn't any emoticon as goofy as that statement) I would appreciate any comments or criticism.

jdallen

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Re: This melt seasons analysis
« Reply #21 on: September 18, 2013, 01:10:52 AM »
 I like the experiment, but I'm afraid it's too simple  ;)

Werther, my condolences as well.

The ice preservation this year is a result of pure energy flow (or lack thereof) into the arctic, rather than anything mechanical.  The salt as it were is already in solution, and the ice in fact mostly FYI which melts typically a little below 29F/-1.5C.

We didn't get enough insolation to warm the top sea surface, and didn't see a lot of surface melt either.  This is a very good thing, as otherwise, with a repeat of 2012 conditions, we might be talking now instead about the last bastion of ice trying to survive in the Lincoln Sea...
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Richard Rathbone

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Re: This melt seasons analysis
« Reply #22 on: September 19, 2013, 01:38:02 PM »
The best experiments are simple. Its a lot easier to repeat them.

What happens if you swap the cups? That's the best way of showing that they are actually identical and one isn't a slightly better insulator than the other.

Was one of them downwind of the other? If the air circulation went from one to the other, rather than being identical for both, the upwind one should melt faster.

How about lighting? If one is a little less shaded, its going to melt faster.

There are some pretty unintuitive things that can happen with natural convection heat transfer. Such as hot water freezing faster. http://arxiv.org/abs/physics/0512262

You might have another one, or you might not. Seeing if it repeats in ways that rule out alternative explanations is the scientific way to establish it.

Weather is the large scale manifestation of oddities in natural convection and is probably the place to look for an explanation of why there is less melt this year than last. However, you could still get an SCYetti effect to add to the Mpemba effect, but not on the basis of just one test. That's your 1% inspiration, there's the 99% perspiration to establish it and characterise it to be done too. And usually the explanation is something simple like one cup having a slightly thicker wall, or one shielding another, but sometimes it isn't.

ChrisReynolds

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Re: This melt seasons analysis
« Reply #23 on: September 22, 2013, 09:40:54 AM »
Richard, SCYeti,

I'm not at all clear why the fresh ice would melt slower in salt water, merely as a function of salt in the water. My best guess would be that perhaps there is a thin layer on the surface of the ice where salt water can locally freeze to the surface of the ice- thus locally raising the salinity and melt point of the ice and slowing net melt by a small degree: 1/8.

I've spent the last hour reading up on the Mpemba Effect - fascinating, I've not read about it before. Nikola Bregović won the RSC's prize for investigating the effect.
http://www.rsc.org/images/nikola-bregovic-entry_tcm18-225169.pdf
He found that stirring the water stopped the effect, suggesting that the major issue is density gradients caused by localised cooling within the body of water. In the Arctic, even under light winds there is mechanical mixing of the water and the temperatures involved are close to the temperature of maximum density (about 4degC). In most of the post 2007 summers surface water temperature has been slightly above 5degC max in the open water regions which does not suggest strong thermally driven density gradients. Furthermore the years of warmest SST - e.g. 2007 and 2012 both show very late re-freezes (IIRC).

So I'm not convinced that the Mpemba effect has a significant role in the Arctic. But I've just had a fascinating hour reading about it - I've never heard of it before, thanks.

BornFromTheVoid

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Re: This melt seasons analysis
« Reply #24 on: September 22, 2013, 12:53:00 PM »
Seems this summer (JJA) had the 5th most +ve NAO since 1979.



What is perhaps even more interesting, was the April to August mean NAO, which was the third highest since 1979, after just 1992 and 1994.  It was also only the 2nd year to have a +ve NAO for every month in the April to August period, with 1992 being the other.



Further comparing 1992 with 2013, the AO for both April to August periods averaged 0.25 and 0.30 respectively. They both followed near record or record lows in the previous year.

1992

2013


When it comes to the PDO, AMO, QBO, ENSO and sunspot count, they were very different though, so I don't know what to make of it!

SCYetti

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Re: This melt seasons analysis
« Reply #25 on: September 30, 2013, 12:54:44 PM »
Chris, the ice I used was fresh water ice with a freezing and melting point of 0C. The ice in the salt water cooled the salt water to 28.8F or almost -2C. Somewhat the same principle as a hand cranked ice cream freezer that cools the ice cream mixture with ice and rock salt.

I stirred both just once. If I had continued the stirring throughout the experiment I am almost certain both would have melted faster. In that case I don't know which would have melted first. The purpose of my little kitchen experiment was to clarify in my mind the source of the low temperatures in the Arctic which of course, is the ice melting. 

I am curious about the mechanics of sea ice freezing and melting. There is a lot more to it than I thought. It seems that the ice loses a significant amount of salt in the initial freezing process, thus brinicles. While salt content lowers the freezing point it doesn't lower the melting point as much, as the salt merely leaches out. This is of course why multi-year ice is nearly salt free.

For me this has been an interesting year. I couldn't predicted any of it.

Andreas T

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Re: This melt seasons analysis
« Reply #26 on: September 30, 2013, 10:04:15 PM »
I learned a lot from this NSIDC description of sea ice formation and properties: http://nsidc.org/seaice/intro.html
In particular that ice crystals do not contain salt even if they are formed in salt water (purification by crysalization is a technique used for other compounds too) this is the "brine rejection" which produces the cold salty water which is found at the bottom of the worlds oceans.
Sea water does not have a density maximum above freezing (4deg C) as fresh water does. Warmer water at greater depth is more dense because it has higher salinity (originating from the more saline atlantic) see measured profiles on the "what the buoys are telling" thread.

In your experiment, SCYetti, you are seeing that ice at 0deg and salt water at 0 deg are not in equilibrium. By melting some ice and diluting the saltwater equilibrium is reached at a lower temperature. To melt more ice energy needs to be added by sunlight or warm air. This melting dilutes the water further, it is this dilution process which takes up some of the energy input in your kitchen experiment. Turning your 8oz of ice into water requires X Joules of energy, diluting the salt water in your cup with 8oz of water requires Y Joules. If energy is added to both cups at the same rate you can see why it takes longer to melt the ice in the salty water.

jdallen

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Re: This melt seasons analysis
« Reply #27 on: September 30, 2013, 10:47:51 PM »
Nice summary Andreas. You have also touched indirectly on what I think is the key dynamic underlying the system - not the seasonal and volatile variations in insolation and local warming, but rather the import of heat via Atlantic currents.  I wonder if the greater seasonal change in ice volume might actually accelerate the movement by way of increased production of brine?
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Pmt111500

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Re: This melt seasons analysis
« Reply #28 on: October 02, 2013, 11:54:33 AM »
one more type of visualization extracted out of the full record. all the years up to sept-27th substracted by 2013 value for the same dates. this essentially sets 2013 values to 0,000 in the y-axis, so the behavior of this specific year can be visually eyeballed.

As may be seen, in January-February 2013 was not doing that great wrt area loss, i.e. 2013 gained more ice early on than usual. March was about similar to other years. April saw a bit speedier loss than usual, followed by a notable slowdown in May.  In June, 2013 was pretty average considering the whole record, but lost a bit ground compared to latest years. In early July, there was a notable catch up with the recent years, also notable might be that (2nd)-3rd week of July in 2013 was nearly exceptional in melt rates. Then 'the stall' started and within 10 days 2013 was again in the post 1998 middle ground, behaving almost normally compared to other years. Some other info might be extractable from here too but I've not done anything more (yet).
Amateur observations of Sea Ice since 2003.

ChrisReynolds

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Re: This melt seasons analysis
« Reply #29 on: October 03, 2013, 07:28:02 PM »
SC Yeti,

Sorry I forgot about your post, was reminded today because I was discussing the issue with the temperature calibration lab chap. Unfortunately we couldn't come up with a solution. But we we're focussing on the temperature of the water as key, wondering if the brine was indeed well below zero deg C instead of being at the triple point (0 degC). I'll ponder it tonight and will get back once I've eaten and my brain is working again.

I suspect it's simply that the brine around the ice is colder because it has a lower freezing point and this protects the ice from as much melting as would happen in the case of pure water.

Andreas,

I doubt it is related to dilution, that's a negligible heat investment when compared to the enthalpy of phase change.

idunno

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Re: This melt seasons analysis
« Reply #30 on: October 06, 2013, 01:12:16 PM »
Having been largely off-line since March, just occasionally dropping in from public libraries, etc, it does seem to have been a most surprising melting season.

The critical factor for the larger ice extent seems to me to be shown here:

http://ocean.dmi.dk/arctic/meant80n.uk.php

From approximately day 120, say 1st May, until approximately day 240, say 1 September, the average temperature North of 80N did not reach the average for the period 1958-present. This surprises me, and I cannot recall anything similar in any recent year.

It is also true of both the late spring, when the average is well below zero, and extra open water should have the effect of raising the air temperature, and of the high summer, when the average line is just above zero.

It seems to me very obvious that if the Arctic is colder then usual for such a long time, it inevitably follows that there will be less melting than (most of us, myself included) anticipated.

Do we have any explanation of why this very extended cold snap might have occurred?

I think that BftV's post on the NAO is interesting.

Apologies if all of this has been well-discussed elsewhere during my absence. Drop us a link and I'll sod off to wherever that may be.

Anyway: cold May + cold June + cold July + cold August = more ice.

That is bloody obvious. The question I woulld like to pose is if anybody can advance an explanation of why May, June, July and August were all cold?

Andreas T

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Re: This melt seasons analysis
« Reply #31 on: October 06, 2013, 02:05:33 PM »
Chris, I am just trying to get a grip on this from basic thermodynamics. How much any of this helps to shed light on what happens in the arctic is another question. My point is basically that thermodynamics applies in the arctic (in ways which are made highly complex by multiple energy inputs /outputs and feedbacks) and thermodynamics applies in scyetis experiment and the various "Mpemba effect" experiments (some of which are poorly observed) I may be barking up the wrong tree here but I often get the impression that people try to bypass thermodynamics when they start to talk about "Mpemba effect" etc.
If I assume that the cups were in the same surroundings and had the same energy uptake from them, we need to look at where that energy goes. Temperature levels do not change that unless they can influence energy transfers e.g. by altering convection. In the case of SCYetis experiment there could be a different pattern of convection from the surface because salt water has a different density / temperature profile. I have to admit to doubts that dilution of salty water takes up a lot of energy, I have not looked up data. (writing this down I realize I should have been less hasty)
None of this can have much bearing on year to year changes in the arctic. That is not to doubt that all sorts of things are changing there longer term, salinity of water at different depths is of course one of them. Root causes of these changes can be things like precipitation changes, changes in currents, wind patterns etc which ultimately are rooted in changes in radiative balance for the planet as a whole, I think we probably agree on that.

Andreas T

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Re: This melt seasons analysis
« Reply #32 on: October 06, 2013, 02:44:40 PM »
this article http://www.awi.de/en/news/press_releases/detail/item/awi_longterm_data_reveal_increase_of_temperature_in_the_deep_greenland_see/?cHash=e61b32ccf86b391b27d270900719af0e
has some bearing, mainly by showing up some of the complexity. It  also shows how winter freezing can move heat into the deep ocean by salinity changes (again very different from my dilution line of argument of course)

ggelsrinc

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Re: This melt seasons analysis
« Reply #33 on: October 06, 2013, 06:09:00 PM »
this article http://www.awi.de/en/news/press_releases/detail/item/awi_longterm_data_reveal_increase_of_temperature_in_the_deep_greenland_see/?cHash=e61b32ccf86b391b27d270900719af0e
has some bearing, mainly by showing up some of the complexity. It  also shows how winter freezing can move heat into the deep ocean by salinity changes (again very different from my dilution line of argument of course)

Good scientists learn to avoid group think and can think outside the box.

Let's put the root question in simple terms! 2012 had the lowest metrics for measuring ASI on record, so the group think was things will be worse in 2013. The root question becomes, why was there so much ASI left in the 2013 minimum?

When the fragmentation event occurred, I asked the group if it could help the ASI, but concept was rejected. The claim was it would produce ASI that is too weak to survive. They also discounted the heat released during the cold period of the fragmentation event, as if it was a bad and not a good thing. I believe the main motivation between our approaches was the group wanted to make a global warming statement of the loss of ASI and I was looking for ways to preserve ASI. I don't have a problem with making a global warming statement, but the price of losing the ASI is too costly for me.

When I examined studies on brine rejection, my assessment was the group think was wrong and sea ice can remove brine faster than they claim. I became convinced the newly formed sea ice following the fragmentation event was stronger than the group think claimed.

ASI owes it's existence to being basically landlocked. It's possible that once ASI has lost so much during the melt season that the sea ice will fragment during times of refreeze forming more sea ice. 

 


Andreas T

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Re: This melt seasons analysis
« Reply #34 on: October 06, 2013, 08:00:55 PM »
I don't get the impression that people here are unable to think independently, there are too many disagreements for that. The fragmentation clearly produced ice, as was noticed in the satellite imagery posted on the blog where leads could be seen to freeze over. Increase in ice volume (in PIOMAS) was not that large, possibly because the surface of the leads were a small part of the ice surface. When people talked of ice being weak I believe it meant the low thickness of the new ice in leads and the open water which would appear in the early summer. This weakness would have been exposed in a sunnier and warmer summer.
What role brine rejection plays in this I don't claim to understand. Again in the year to year difference to 2012 it should depend on the  difference of volume gain(and possibly locality of gain ) in the wintermonths. How would it make ice stronger? The warming (long term and relative to previously very low temperatures) of deep water could possibly happen in combination with increased atlantic water (medium density "warm" but saline) inflow, i.e. not reducing (relative to previous again) heat available for bottom melt.
 I agree that sometimes people here overemphasise the possibility of increased melt, I see that as a byproduct of dealing with indifference and denial. This summer has shown all of us that the arctic does things its own way and Neven repeatedly reminds us of that too.
I personally have my doubts that extrapolating the curve of past years leads to good predictions (I'd like to see a mechanism to go with that) but it is right to take what has happened (in 2012) as a warning and avoiding bad outcomes even if we are not sure how soon they will happen is a goal for many people here I think.

ggelsrinc

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Re: This melt seasons analysis
« Reply #35 on: October 06, 2013, 09:30:49 PM »
I've seen situations where scientists were the best in their field and still had problems with group think. They run into a problem and continue to go down the same path leading to Nowhereville, trying to solve the problem. Science teaches us to be skeptical of everything and we have to constantly test what we think we know, until it is a certainty reviewed so many times there is no chance it is wrong. Even a super-genius has limitations, because we are all humans with fallacies.

I believe if ASI is fragmented during a period when sea ice is forming, it will vent heat and make more sea ice and that's only logical. I think the critical factor is it only has to be cold enough to make sea ice and any heat escaping the arctic ocean during such cold periods is a good and not a bad thing for ASI. Yes, it makes the arctic warmer when it happens, but that warmth is very temporary. Factors like the sea ice insulating the warmer ocean below are more important. Factors like increasing sea ice volume are more important.

Originally I was just looking for ways to make MYI, because I was told how important it is. I was wondering, if it was possible to create enough sea ice of good enough quality to fill the landlocked area and return us to pre-satellite days. I knew factors like sea ice covered in snow is thinner, because it increases insulation, unless there is too much snow cover causing it to be weighed down and the ocean mixing with the snow and freezing. I knew how dynamic sea ice was and that's why I was interested in it.

I asked if there was good research on brine rejection for sea ice, but was told how easy it was to find. I don't claim what I found on my own was the best research, but my assessment was sea ice can reject brine and strengthen more quickly than I was led to believe.

My analysis of this melt season is it was due to the fragmentation event. I think the fragmentation event occurred, because the ASI was critically low. I consider that good news, because I don't see governments presently responding to climate change. It's always been too much talk and not enough do. 

 

 

idunno

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Re: This melt seasons analysis
« Reply #36 on: October 07, 2013, 09:24:18 AM »
wayne has some theories about cloud cover causing the cold summer, and now a warm autumn,  with discussion of an unusual, and persistent 'bipolar ENSO' pattern over on his blog:

http://eh2r.blogspot.ca/


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Re: This melt seasons analysis
« Reply #37 on: October 07, 2013, 01:41:03 PM »
My entry to the shortest melt season analysis contest: One of the coldest summers led to the sixth lowest September sea ice extent in the satellite era.

Conclusion: Sea ice extent is borked.
« Last Edit: October 07, 2013, 02:25:52 PM by arcticio »

idunno

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Re: This melt seasons analysis
« Reply #38 on: October 08, 2013, 05:43:10 PM »
In reply to my earlier post about this melt season being especially cold, well I am no longer so sure that 2013 stands out as such an exception.

There are several other recent years, in particular 2004, which seem to have been consistently below the average line during the months of May through August.

http://ocean.dmi.dk/arctic/meant80n.uk.php

Flicking through various years of the 21st century, it seems to me that almost all of the heat spikes are occurring during winter and, especially, autumn.


ChrisReynolds

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Re: This melt seasons analysis
« Reply #39 on: October 08, 2013, 06:39:20 PM »
Idunno,

You can't really say anything about Arctic temperature long term using that DMI site because it uses ERA40 reanalysis. There's a paper that found a problem with that sytem, and I don't know if they've fixed it yet.
http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI4054.1

However I am not aware of similar problems with NCEP/NCAR and they do have a feature to plot graphs.
http://i1272.photobucket.com/albums/y396/RobDekker/a6be7b5a-12f3-4200-a636-bf4362ce7ba5_zps91bdfe95.jpg
That's from Rob Dekker - NCEP/NCAR is down due to the US having voted in a bunch of irrational nutcases (tea party types). I'm in the middle of downgrading back to Vista from Windows 8 (which is crap) so aren't in a position to post graphs right now.

idunno

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Re: This melt seasons analysis
« Reply #40 on: October 09, 2013, 09:06:12 AM »
Thanks, Chris,

I realised yesterday that there was some contradiction between what I have posted above and what Rob has posted on the main arctic Sea Ice blog, on the current most recent thread:

http://neven1.typepad.com/blog/2013/09/pinpointing-the-minimum.html?cid=6a0133f03a1e37970b019affd8ed25970c#comment-6a0133f03a1e37970b019affd8ed25970c

This expains most of the confusion, and I would agree that Rob's data is better quality, and his graph much clearer than my subjective impressions from eyeballing the DMI graphs.

So I'm taking one step back, withdraw my comment of yesterday correcting my earlier post, and go back to what is for me the 64 mil question of 2013;

cold May + cold June + cold July + cold August = more ice

If Rob's graph does not show that every date during this spell was below the recent average, it definitely confirms that the whole period, averaged, was unexpectedly cold.

If we are interested in why there is more ice, is it easier to advance explanations of why May-Aug were unexpectedly cold North of 75°?

i.e. Is it easier to address the left hand side of the equation above?

I' d be particularly interested in your thoughts, as I know you've done quite a bit previously on the different rates of seasonal change.

Finally, and controversially, and I'd like to preface this by volunteering the irrelevent confession that I think that Joe Bastardi is a complete and utter dickheadi, but,

'Could the small melt of 2013 be a sign that the AMO has entered its cool phase?'

http://en.wikipedia.org/wiki/Atlantic_multidecadal_oscillation

Not a very good moment to pose this question as, for the reasons that Chris correctly states above, the NOAA site which tracks it is offline.

Neven

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Re: This melt seasons analysis
« Reply #41 on: October 09, 2013, 05:42:17 PM »
If I remember correctly the AMO is mostly about how much 'warm' Atlantic water is going how far north. On the Atlantic side of the Arctic the melting was pretty fierce. It's on the other side, the Pacific/Siberian side, where the lack of melting mostly took place. Now if the AMO can influence atmospheric patterns up to that point and all of the Arctic, then by all means it's the AMO.
Compare, compare, compare

idunno

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Re: This melt seasons analysis
« Reply #42 on: October 09, 2013, 06:52:46 PM »
Hi Neven,

Judith Curry has a post up which touches on this, which refers to the discussions at a symposium in Taiwan [though from what I could see, majority of the material suggests the opposite of what Judith says it does]

http://www.tims.ntu.edu.tw/workshop/Default/program.php?WID=137
 
In this context, the talks by Keenlyside, by Tung and, especially, by Walsh are very interesting.

Personally, I am fairly convinced that the AMO [or AMV, perhaps] has global influence on climate.

Direct link to the Walsh notes, as they include a breakdown of seasonal temp anomaies, which I have mentioned above. The Arctic has indeed warmed much more in winter.

http://www.tims.ntu.edu.tw/Talks_detail.php?talkID=2311

...and plenty of other interesting stuff, absolutely none of which is likely to relate to melt 2013, so I may well be posting this on the wrong thread.


ggelsrinc

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Re: This melt seasons analysis
« Reply #43 on: October 09, 2013, 10:21:37 PM »
Being horse poor, I haven't scheduled a dental appointment for this year's melt season's gift horse, because I'm simply too glad to get the horse. When the conservative British Prime Minister Margaret Thatcher said global warming is the greatest threat mankind has faced, our conservative President Ronald Reagan was sleeping and the world has been sleeping ever since. Having spent my days in America, I wish we would have done better, but we didn't. I consider myself fortunate to live in an area that doesn't elect such clowns to office, but enough of politics.

I've been hoping for some negative feedback to occur in the arctic to buy us time and I don't consider my fragmentation event explanation a theory, because there is no data to support it. I have considered increases in cloud cover or cloud forcing to become a negative feedback in the arctic, but again no analysis because of poor data. Contributions of aerosols from Europe and volcanos have also been considered. The weird recent changes in ENSO or other climate pattern possibilities have been considered. A multiple causation has been considered.

idunno-

I don't know, nor do I pretend to know; I'm merely discussing some things observed. Two heads are better than one, even if one is a cabbage head.     


Neven

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Re: This melt seasons analysis
« Reply #44 on: October 09, 2013, 11:22:34 PM »

In this context, the talks by Keenlyside, by Tung and, especially, by Walsh are very interesting.

Thanks, interesting indeed.
Compare, compare, compare

ChrisReynolds

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Re: This melt seasons analysis
« Reply #45 on: October 12, 2013, 10:31:18 PM »
Idunno,

Sorry for the delay in getting back to you, mixture of new OS updating a lot and work commitments.



That's a graph of NCEP/NCAR surface temperature anomalies from 1981 to 2010 average for 2007 to 2012 by month. i.e. the difference from average. It's from this post:
http://dosbat.blogspot.co.uk/2013/04/giss-loti-and-ncepncar-reanalysis.html
The region covered is poleward of 70degN from 100degE to 230degE, area weighting used so land effects are negligible.

You can see that during the summer are small, that's because excess energy doesn't go into warming things up, it goes into melting ice. The positive anomalies are largely due to open water (I think).

Then in October anomalies are massive. This is as a result of large areas of open water where there was once ice which would drop to well below freezing through October. The open water is venting enormous amounts of energy gained over the summer into the atmosphere before it can freeze.

However even when it has frozen thoughout the winter temperatures remain anomalously high because of heat venting through thinner ice (thinner than typical for the whole period 1981 to 2010. I have a post written examining the relationship between thinning and temperature but need to re-work. I did the calculations on March/April/May, here's surface temperature for MAM plotted with PIOMAS April thickness for the region 70degN to pole and 30degE to 190degE.



I've had to rework because at this time there is no trend in MAM heat flux from ice to atmosphere, which is because calculated heat flux in March is rising, April is level, while May is falling (probably related to the increasing influence of the sun which rises in March), so I need to move back to DJF or JFM to avoid that problem. Unfortunately NCEP/NCAR is down.

Anyway new blog post here about Siberian and Greenland geopotential height.
http://dosbat.blogspot.co.uk/2013/10/siberian-and-greenland-geopotential.html

idunno

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Re: This melt seasons analysis
« Reply #46 on: October 13, 2013, 01:40:11 PM »
Hi Chris,

Thanks for that. I'd add that there is also a peak in May; and that the thinness of winter ice allows more heat flux to the atmosphere because thin ice is more prone to cracking. I once read some Russian research showing that heat flux from a lead can be 100x the heat flux through the ice itself.

My current interest is in trying to determine if I think that the unexpectedly low melt in 2013 is just an unexpectedly low bit of random noise, or whether it is a result in a major regime shift in the Arctic, due to some sort of natural cycle: imho, the AMO/AMV being the most likely candidate.

Happiest to suggest this here, as you and I have politely agreed to disagree about issues relating to Atlantic water before; Long live polite disagreement!

I am concerned that 2013 does actually look like the possible start of a genuine recovery in the sea ice, and is different from the false recoveries of 2008, 2009, 2010, 2011. The difference being that in the case of 2013, there is an upturn in PIOMAS, and the PIOMAS data has certainly departed from the exponential downward trend line.

In addition to the Walsh lecture notes, and the paper from Wyatt (and Curry), there is now a new paper from Li related to this area. There is a review of a review of it here:

http://wottsupwiththatblog.wordpress.com/2013/10/13/watt-about-a-cessation-of-global-warming/

which saves me an awful lot of typing, as it carefully lists a whole pile of important caveats, with all of which I agree.

The link in the first paragraph of that piece - to the "Hotwhopper" blog - is also interesting, as it shows the way in which this important research - and any change in the rate of ice melt, if it is proved corrrect - can and will be misrepresented.

Anyway, my question is whether it is possible, and worth considering, that we may be on the cusp of turning from a phase of the natural cycles which have amplified the melt due to anthropogenic forcings (co2 + black carbon combined) + polar amplification, into a regime where the multidecadal ocean patterns counteract and thus dampen the effect of anthropoforcings and polar amplification.

I should say that the one data point of Sep 2013 is little to go on. It also occurs that the system is exhibiting chaotic variation suggestive of possible imminent collapse, and I doubt if we will have any clear idea until sometime in about 2017.

Anyway, FWIW, I am now prepared to consider the idea that the ice may be about to act similarly to SATs on the SkScience "up-escalator" graph - that we may soon develop a horizontal tread of the ASI "down-escalator".

P.S. Whilst this is addressed to Chris, please all feel free to fire away. Do I get a blindfold?

bluesky

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Re: This melt seasons analysis
« Reply #47 on: October 13, 2013, 02:50:37 PM »
Although I missed most of the melting season, an article regarding the importance of the early melting season in May was mentionned several time in the blog. I just wonder, as the early melting seasonal was rather cold and subsequently the open water in Beaufort sea was very slow to appear and grow in May and early June, it had an effect on the whole melting season. In a nutshell, it might be that there was not enough open water at the beginning to create an amplification  melting factor that we saw in nearly all melting season 2007-2012 from mid end June onward? Was it helped by the fragmentation and above all by the persistent Arctic low pushing and spreading the ice toward the peripherial Arctic, Beaufort and Chukchi sea? So would it be that if a certain "tipping point" is not reached around mid - end June, the melting season end with a much higher sea ice area? Do we have any other example like that in the past, or maybe my questions are completely irrelevant?!
On the AMO, I remember reading an article a few years ago that there might be a correlation between the Alps glaciers melting and the AMO, considering what has happened this year, I would not be surprised if the SMB of most of Alps glacier would be positive for the first time for many years, would it be another clue that the AMO is turning to a new phase?
Another question, snow extent in Northern hemisphere was really high at the end of April, one of the biggest extent (ranked 9th biggest out of 47 years, and even 3rd biggest extend for North America according  Rutgers, and you would probably need to go back 15 to 20 years earlier for such a high ranking). Although it came back within the lowest extent at the end of May (45 out 47, but not for North America 29th), could this had had an effect on the Arctic cold weather in May?  Did it prevent the "recent shift in early summer Arctic atmospheric circulation" noticed by Overland et al that happened during 2007-2012, or my questions are completely irrelevant?

ChrisReynolds

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Re: This melt seasons analysis
« Reply #48 on: October 13, 2013, 07:05:09 PM »
Idunno,

In 2010 PIOMAS shows that there was a severe depletion of MYI and a drop in average thickness. There was no rebound from that event, unlike the 2008 rebound from 2007. Since 2010 we have seen two records in CT Area (2011 and 2012), and 2007 being met with 2012 a new record (various extent series).

Following 2010 we have seen a state where the pack is predominantly FYI. Forecasts using PIOMAS and various modelling (GCM) studies show that enhanced production of ice volume in autumn/winter counters the trend of volume loss causing volume loss to reduce and a tail of persistent late summer ice to develop. There is no involvement of AMO or any other climatic cycle in this, just ice dynamics.

This year was weather driven. As Bluesky points out we must look to events before the summer season to understand 2013. Volume from PIOMAS over winter was level with the last three years (see previous paragraph), Cryosat 2 shows a small decline over the same period. It was in May that PIOMAS volume started to show an increase on 2012 at the same time. This was not a recovery, it was weather driven. I have seen no evidence to suggest this years weather was due to climate cycles and I regard it as a one off. I expect conditions more typical of 2007 to 2012 next year.

Once late June Ct Area was higher than previous years the situation was probably (at least 75% probability) set for the rest of the summer, as my successful prediction method showed.

Next year will see a volume increase over winter (JFM) compared to 2011, 2012, 2013. This will not be a recovery it will be the feed through of increased volume due to the cold start to 2013's melt season. Future years may see a maintenance of the winter volumes of 2011 2012 and 2013, this will not be because of the AMO or any climate cycle or "crowd wave", it will be because autumn/winter volume growth is responding to low area/extent at the end of the season. This will be shown if autumn/winter volume gains remain above pre-2007 levels.

The only tests of a 'recovery' due to something like the negative AMO phase will be if summer minima start to revert back to pre-2007 levels, and if volume levels climb back to pre 2010 levels. On the strength of the evidence of 2013 these criteria are not going to be met the coming winter, and I do not expect them to be met. Furthermore the following graphic shows the PIOMAS volumes of ice in April for ice below and above 2m thick, this will be a key indicator to watch, a recovery of the ice would mean overall volume increasing and ice transferring from the less than (<) 2m category into the greater than (>) category. This winter will see a small increase, but will not recover to pre 2010 let alone pre 2007 state.



Bluesky,

I agree with your first paragraph. See my blog post, linked to at the end of my comment above with graphics. Snowline in May 2013 did retreat far enough to possibly play a role in forming an atmopsheric ridge this year. In terms of the atmosphere I think the late start to the melt season prevented the formation of the atmopsheric pattern seen in Overland et al, affecting weather as far away as the UK. But crucially preventing a more aggressive melt in the Arctic.

As NCEP/NCAR is down at present I can't check out average temperatures over the Alps, but again; I really think people are reading too much into these climate cycles.

idunno

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Re: This melt seasons analysis
« Reply #49 on: October 14, 2013, 11:00:24 AM »
Thanks for that Chris.

I agree that 2 metre thickness in April seems to be a good measure to follow.

There follows one of the best analyses I've read yet of the cause of the persistent stormy weather through early summer 2013...

http://climatechangepsychology.blogspot.fr/2013/06/N-Hemisphere-Atmospheric-Circulation-Collapsed-Creating-Persistent-Polar-Cyclone.html

Perhaps there is a new pattern to be expected, where as per Francis, the polar vortex weakens and wanders, and then, Nature abhorring a vacuum and all that, can suddenly reestablish itself in a very pure form. Thinking aloud...