Remember that 'unprecedented' Greenland ice sheet surface melt that was allegedly caused by global warming? Never mind

We covered this extensively at WUWT last summer, including the “unprecedented claim” where a researcher said it was a recurring 150 year event that was ‘right on time‘. It turns out jet stream changes and thin cloud cover was the driver. Also “the analysis shows that ocean temperatures and Arctic sea-ice cover were relatively unimportant factors in causing the extra Greenland melt.”.

From the University of Sheffield

Jet stream changes cause climatically exceptional Greenland Ice Sheet melt

The research team at the GrIS

Research from the University of Sheffield has shown that unusual changes in atmospheric jet stream circulation caused the exceptional surface melt of the Greenland Ice Sheet (GrIS) in summer 2012.

An international team led by Professor Edward Hanna from the University of Sheffield’s Department of Geography used a computer model simulation (called SnowModel) and satellite data to confirm a record surface melting of the GrIS for at least the last 50 years – when on 11 July 2012, more than 90 percent of the ice-sheet surface melted. This far exceeded the previous surface melt extent record of 52 percent in 2010.

The team also analysed weather station data from on top of and around the GrIS, largely collected by the Danish Meteorological Institute but also by US programmes, which showed that several new high Greenland temperature records were set in summer 2012.

The research, published today in the International Journal of Climatology, clearly demonstrates that the record surface melting of the GrIS was mainly caused by highly unusual atmospheric circulation and jet stream changes, which were also responsible for last summer’s unusually wet weather in England.

The analysis shows that ocean temperatures and Arctic sea-ice cover were relatively unimportant factors in causing the extra Greenland melt.

Professor Hanna said: “The GrIS is a highly sensitive indicator of regional and global climate change, and has been undergoing rapid warming and mass loss during the last 5-20 years. Much attention has been given to the NASA announcement of record surface melting of the GrIS in mid-July 2012. This event was unprecedented in the satellite record of observations dating back to the 1970s and probably unlikely to have occurred previously for well over a century.

“Our research found that a ‘heat dome’ of warm southerly winds over the ice sheet led to widespread surface melting. These jet stream changes over Greenland do not seem to be well captured in the latest Intergovernmental Panel on Climate Change (IPCC) computer model predictions of climate change, and this may indicate a deficiency in these models. According to our current understanding, the unusual atmospheric circulation and consequent warm conditions of summer 2012 do not appear to be climatically representative of future ‘average’ summers predicted later this century.

“Taken together, our present results strongly suggest that the main forcing of the extreme GrIS surface melt in July 2012 was atmospheric, linked with changes in the summer North Atlantic Oscillation (NAO), Greenland Blocking Index (GBI, a high pressure system centred over Greenland) and polar jet stream which favoured southerly warm air advection along the western coast.

“The next five-10 years will reveal whether or not 2012 was a rare event resulting from the natural variability of the NAO or part of an emerging pattern of new extreme high melt years. Because such atmospheric, and resulting GrIS surface climate, changes are not well projected by the current generation of global climate models, it is currently very hard to predict future changes in Greenland climate. Yet it is crucial to understand such changes much better if we are to have any hope of reliably predicting future changes in GrIS mass balance, which is likely to be a dominant contributor to global sea-level change over the next 100-1000 years.”

###

In a story at RedOrbit the scientists report:

Scientists have been trying to determine what led to the 50-year-record ice melt in Greenland. In April a team of scientists wrote in the journal Nature that they determined that the ice melt could be due to thin cloud cover.

h/t to junkscience.com

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Lawrence13
June 17, 2013 1:46 pm

“Remember that ‘unprecedented’ Greenland ice sheet surface melt that was allegedly caused by global warming? Never mind”
How could I forget I still can’t move for tripping over sandbags !!!!

Ian W
June 17, 2013 1:54 pm

Stephen Wilde will agree with this one – it all comes back to the jet streams, Rossby waves, and the Ferrel and Hadley cells. They are influenced by the ocean heating due to short wave and ultra-violet and the modulation of the SST due to cloud cover and albedo changes.

rgbatduke
June 17, 2013 1:56 pm

Sigh. Yet another case of “we have no idea why it happened, we didn’t predict it, we cannot predict it, it had profound consequences, the models that should have predicted it didn’t” that still manages to avoid concluding that a) the GCMs were wrong yet again and hence cannot be trusted and b) that this wasn’t actual evidence of CAGW after all. Because even though we could not predict the diversion in the jet stream, even though we do not know exactly what caused it or what caused the causes of it or what caused the causes that caused the causes of it (iterate back to the big bang) we can of course be certain that we humans caused it with our carbon dioxide.
Is there actually any such thing as science any more. Can’t anybody say the magic words “we don’t know what caused it”, perhaps in association with “models that should have predicted it failed. Again.
I’m curious as to what the UAH or RSS LTT are going to be doing this month. Temperatures outside in Beaufort have remained (or so it seems to me) cooler than they have been for the last four years for the time of year with only a few days of hot and muggy and quite a few days of almost chilly. The water temperature is also still quite cool, and it has negatively affected the fishing quite extraordinarily compared to the last two years, at least. Even my next door neighbors, who have lived here forever and who almost never fail to catch all the fish they want have come home empty handed for pretty much the second half of May and entire month of June so far. Yes, I know, this is semi-anecdotal except that the temperatures are usually regulated by the Gulf Stream flowing up the coast only 20 miles offshore, and so when inshore temperatures remain cooler than usual one wonders what the Gulf Stream is doing. The North Atlantic SST map on the weather underground shows the coastal water still in the 70s and a lot of the Atlantic still in the 70s with only a comparatively thin plume of 80s offshore, but I can’t mentally compare this with the map on similar dates over the last few years and don’t trust my memory.
I do hope that the fishing, at least, heats up soon though. The weather can stay as cool as it likes, for summer;-).
rgb

arthur4563
June 17, 2013 2:12 pm

Another Emily Latella moment.

Jimbo
June 17, 2013 2:24 pm

No matter what is debunked they will continue to play the man-made global warming blame game. Next.

June 17, 2013 2:25 pm

New paper finds Greenland surface melt was due to natural variability
http://hockeyschtick.blogspot.com/2013/02/new-paper-finds-brief-greenland-surface.html
Last summer, the mainstream media breathlessly reported that a brief 4-day surface melt over the Greenland ice sheet represented evidence of man-made global warming. However, a paper published today in The Cryosphere finds that “the recent warmer summers over [the Greenland ice sheet] cannot be considered as a long-term climate warming but are more a consequence of [the natural North Atlantic Oscillation] variability affecting atmospheric heat transport.” In other words, the brief Greenland surface melt was related to natural variability rather than alleged man-made global warming.

Resourceguy
June 17, 2013 2:26 pm

And it never stopped melting in the minds of the 97% consensus, or least the contrivers of the 97% claim.

taxed
June 17, 2013 2:28 pm

lt looks like at long last that climate science is waking up to just how important the jet stream is to the climate in the NH. l think underplaying its importance has been one of climate science’s biggest mistakes. My own interest in the weather and later the jet stream is leading me to think it was changes to the jet stream that set up the ice age.

Latitude
June 17, 2013 2:38 pm

unprecedented, exceptional, catastrophic……
Has anyone else noticed you have to be a drama queen to report the weather?
” and probably unlikely to have occurred previously for well over a century.”
““The next five-10 years will reveal whether or not 2012 was a rare event”
….we have our feet firmly planted on the ground
“The analysis shows that ocean temperatures and Arctic sea-ice cover were relatively unimportant factors in causing the extra Greenland melt.”
“that the record surface melting of the GrIS was mainly caused by highly unusual atmospheric circulation and jet stream changes,”
..well thank goodness it was contained in the GrlS…and didn’t affect Arctic sea ice

Myron Mesecke
June 17, 2013 2:57 pm

Please excuse my ignorance. Could the change in the circumpolar vortex from zonal flow to meridional flow have contributed?
Dr. Tim Ball talked about this change in June of 2012.
http://drtimball.com/2012/current-global-weather-patterns-normal-despite-government-and-media-distortions/

taxed
June 17, 2013 3:10 pm

A similar weather pattern to the one last summer also happen in Nov/Dec of 2010.
Where a Greenland set up in the north Atlantic and drew the jet stream northwards over Greenland bringing warm air and high temps for the western side of Greenland. But for the UK on the other side of the Atlantic it brought down a Arctic blast.

taxed
June 17, 2013 3:13 pm

Sorry meant to write “Where a Greenland high set up in the north Atlantic”.

Gary Hladik
June 17, 2013 3:28 pm

rgbatduke says (June 17, 2013 at 1:56 pm): “Can’t anybody say the magic words “we don’t know what caused it”, perhaps in association with “models that should have predicted it failed. Again.”
A lot has been written on WUWT lately about GCM shortcomings, much of it by RGB. So when I was reading this article the sentence
“These jet stream changes over Greenland do not seem to be well captured in the latest Intergovernmental Panel on Climate Change (IPCC) computer model predictions of climate change, and this may indicate a deficiency in these models.”
really jumped out at me. We might as well predict the state of the climate system in 2100 this way. It’s cheaper and might actually (by chance) give the correct answer.

June 17, 2013 3:42 pm

‘has shown that unusual changes in atmospheric jet stream circulation
caused the exceptional surface melt of the Greenland Ice Sheet’ and what causes ‘unusual….jet stream’? Well that would be AGW of course! Heads I win, tails you lose!

wikeroy
June 17, 2013 3:56 pm

Hey! They forgot to use the word “unequivocal” !!!

June 17, 2013 3:57 pm

“…probably unlikely to have occurred previously for well over a century”
Pure supposition.
That’s not science, it’s just b*llsh*t

jai mitchell
June 17, 2013 4:09 pm

Myron Mesecke
Yes, that is basically what they are saying. A blocking pattern left a dome of high pressure over Greenland causing unprecedented melt. In the summary of the article it says, ”
“Taken together, our present results strongly suggest that the main forcing of the extreme GrIS surface melt in July 2012 was atmospheric, linked with changes in the summer North Atlantic Oscillation (NAO), Greenland Blocking Index (GBI, a high pressure system centred over Greenland) and polar jet stream which favoured southerly warm air advection along the western coast
We know from the studies of Jennifer Francis that arctic amplification has weakened the polar jet stream this year, this has severely increased meridional flow to the rossby waves of the jet stream.
Here is her short explanation.

TomRude
June 17, 2013 4:14 pm

The jet stream causes high pressure systems to stay… sure… have another glass.

george e. smith
June 17, 2013 4:25 pm

“””””…..An international team led by Professor Edward Hanna from the University of Sheffield’s Department of Geography used a computer model simulation (called SnowModel) and satellite data to confirm a record surface melting of the GrIS for at least the last 50 years – when on 11 July 2012, more than 90 percent of the ice-sheet surface melted. This far exceeded the previous surface melt extent record of 52 percent in 2010…….”””””””
I thought if the Greenland Ice Sheet melted, that the sea level would rise 200 feet, or 60.96 meters, whichever comes first.
So 90% melt would only be 55 meters or 180 feet.
And back in 2010, when 52% melted, the sea level rise was just 104 feet or so. Can’t say it had much effect on San Francisco Bay. Well it might have been the cause of a couple of catastrophic Americas cup, catamaran pitch pole capsize calamities, in the bay; one fatal.
Oh! I see they say “surface” melted, not “ice sheet melted”. Well that would be just the one molecular layer on the top side of the ice sheet I suppose.
And they say all of this happened right before their eyes on a computer screen outputting a model simulation.
Whew! had me worried for a bit, that it might have been real.
Well they do say that a satellite confirmed it by watching for the last 50 years, back to 1962; just 5 years after Sputnik.
I didn’t even know they has a satellite in 1962 that could observe, let alone measure the top molecular layer of Greenland ice sheet.
And this jewel:- “””””….. – when on 11 July 2012, more than 90 percent of the ice-sheet surface melted. This far exceeded the previous surface melt extent record of 52 percent in 2010……”””””
Now by my calculation, 90% is an increase over 50 %, of just 73.1 %, or 1.73 x if you prefer.
Now you see we just don’t know the value of the climate sensitivity, to within a factor of 1.73, so if that is all that the change was, why all the hyping about “””…far exceeding….”””
They really should have said: “we don’t know if the simulated change is statistically significant or not, as climate data goes.
They need to tone down their use of superlatives. 90% does not “far exceed” 52% in climate terms.
Does anybody know if the top molecular layer of Greenland ice gives you enough ice water to cool down rgbatduke, who is having a fit over the lousy Carolina fishing. Well ProfBob, If I had Carolina fishing off California, instead of an explosion of furbags, I’d be pretty steamed about the situation too.

Reich.Eschhaus
June 17, 2013 4:35 pm

[Snip. Off topic. — mod.]

alice
June 17, 2013 4:37 pm

here’s the headline over at ThinkClimate. “Exceptional 2012 Greenland Ice Melt Caused By Jet Stream Changes That May Be Driven By Global Warming”

Phil.
June 17, 2013 4:49 pm

“The next five-10 years will reveal whether or not 2012 was a rare event resulting from the natural variability of the NAO or part of an emerging pattern of new extreme high melt years.”
This year is shaping up similarly so it will be interesting to see how it plays out.

MichaelS
June 17, 2013 5:40 pm

Reich.Eschhaus says:
June 17, 2013 at 4:35 pm
(Note: “Plain Richard” is a sock puppet for Reich.Eschhaus. This is in violation of site Policy. Comments snipped. Further infractions will result in a permanent ban. ~mod.)”
No worries. My housemate known here as Richard is not going to comment here anymore (for obvious reasons). Neither will I comment here anymore (solidarity with a friend I live with). Actually there are 7 persons here who share the same internet connection. I am sure you won’t mind. So Bye Bye!
____________________________________________________________________________
*wipes away a tear*

June 17, 2013 6:56 pm

I was looking at the sea ice page after seeing this, curious why it still uses 2007/2013 comparisons when last year was the low point, wasn’t it?

JimF
June 17, 2013 7:31 pm

Sure wish that “global warming” would happen. We have a frost warning on for much of the Upper Peninsula (Michigan) tonight.

Eli Rabett
June 17, 2013 8:15 pm

Jennifer Francis would ask what moved the jet stream.

Theo Goodwin
June 17, 2013 8:49 pm

MichaelS says:
June 17, 2013 at 5:40 pm
Running across a virgin troll is a rare event. Discovering one that has no hope of promotion in troll grade is a truly rare event. Reich.Eschhaus has shot across the screen and is no more.

Theo Goodwin
June 17, 2013 8:56 pm

alice says:
June 17, 2013 at 4:37 pm
‘here’s the headline over at ThinkClimate. “Exceptional 2012 Greenland Ice Melt Caused By Jet Stream Changes That May Be Driven By Global Warming”’
And the mechanism for this is…
Interesting how rising CO2 caused a shift in the jet stream and that shift coincidentally caused an effect in Greenland that Alarmists have long awaited and long ago attributed to other causes.
Man, Alarmist climate science is a botch.

David
June 17, 2013 9:18 pm

Phil. says:
June 17, 2013 at 4:49 pm
“The next five-10 years will reveal whether or not 2012 was a rare event resulting from the natural variability of the NAO or part of an emerging pattern of new extreme high melt years.”
This year is shaping up similarly so it will be interesting to see how it plays out.
===============================================
Is a plus one million sq K of sea ice similar. For how many minutes did some 97 percent of Greenland Ice melt?

Brian H
June 17, 2013 11:46 pm

The distinction between area and volume is apparently beyond some people’s purview and comprehension.

Spence_UK
June 18, 2013 12:36 am

I have to say I really dislike the statement “jet stream changes caused…”, much like the implication that the jet stream “caused” wet weather in the UK.
The jet stream is not a root cause, it is a correlated pattern with common cause to the blocking weather system in the turbulent atmospheric dynamics. The turbulent atmospheric dynamics follow the same behaviour originally formulated by Kolmogorov seventy years ago, in which the system can exhibit unpredictable shifts for arbitrary periods of time. By assigning causes, people mistake this for some kind of predictable behaviour. It isn’t.
This is all normal natural variability. But it is wrong to say it is “caused” by the movement of the jet stream. The jet stream, blocking systems and temperature changes have common cause in the natural variability of the turbulent dynamics of the atmosphere.

Stephen Richards
June 18, 2013 1:22 am

rgbatduke says:
June 17, 2013 at 1:56 pm
I’m with Robert. They simply can’t say NO, I don’t know.
Spence_UK says:
June 18, 2013 at 12:36 am
A common cause in science at the moment. They can never seem to find the source of the change only the symptoms.

DirkH
June 18, 2013 1:29 am

Eli Rabett says:
June 17, 2013 at 8:15 pm
“Jennifer Francis would ask what moved the jet stream.”
That is very nice indeed, rodent; but the point is that climate science has successful hindcasts, never successful forecasts, and if climate science would admit that I guess we were all much happier. Unfortunately climate science insists on giving advice to policymakers in their IPCC reports as if they knew anything about the future, which they demonstrably don’t.

izen
June 18, 2013 1:39 am

@-“The research, published today in the International Journal of Climatology, clearly demonstrates that the record surface melting of the GrIS was mainly caused by highly unusual atmospheric circulation and jet stream changes, which were also responsible for last summer’s unusually wet weather in England.”
Ascribing something to a unusual, but ‘natural’ variation is NOT an explanation, just a description.
It begs the question; Why does this unusual natural variation happen, what are its causes.
The extreme rarity of the Greenland melting event, at least since 6000 years ago when the perihelion was in the N. hemisphere summer, indicates that this natural variation is exceptional and the result of exceptional and extreme events in the climate.
The Greenland total surface melt, and the precipitous drop in summer ice, are just more examples of the increasing variation caused by the accumulating thermal energy in the climate system. The Lance Armstrong climate is exhibiting more variation because of the vast amounts of energy that the oceans have absorbed over the last few decades.

izen
June 18, 2013 1:46 am

@-DirkH
“Unfortunately climate science insists on giving advice to policymakers in their IPCC reports as if they knew anything about the future, which they demonstrably don’t.”
They have a rather better track record since the sixties on predicting the increasing energy which is mainly going into the oceans. The evidence for that is unequivocal and robust and there have been no other explanations for that massive accumulation of energy in the oceans. Attempts to implicate clouds or solar variation altering cosmic ray or UV factors have failed repeatedly to provide a physical explanation for the observed energy changes.
Given that it is vital for any responsible government to get the best information about how things may develop in the future, and the massive agreement among scientists {97%!} in the accuracy of the AGW explanation along with the obvious paucity of any alternative explanation and failure of any other hypothesis to predict the observed changes over the last few decades it is difficult to see who else responsible politicians should consult for accurate information about the future climate.

johnmarshall
June 18, 2013 2:37 am

The good Professor reports that the melt was the largest since satellite records started, 1979, but then failed by claiming that this may not have happened for the past hundred years. There is no basis to make that claim. We know that 1940 was a very low Arctic ice year so it could have happened then but no data means such a claim cannot be made.
Stick to the facts.

Billy Liar
June 18, 2013 3:27 am

johnmarshall says:
June 18, 2013 at 2:37 am
From firn cores at Summit Camp in Greenland so we know that the previous time there were >0C temperatures there was in the late 19th century (1889). When sufficient firn cores have been taken over the rest of the area of Greenland we’ll have some data.
http://dartmouthigert.wordpress.com/2012/07/21/new-summit-melt-layer/

Bruce Cobb
June 18, 2013 4:23 am

izen says:
June 18, 2013 at 1:46 am
The Lance Armstrong climate is exhibiting more variation because of the vast amounts of energy that the oceans have absorbed over the last few decades.
Show your work.

izen
June 18, 2013 4:31 am

@- Billy Liar
“When sufficient firn cores have been taken over the rest of the area of Greenland we’ll have some data.”
We already have a LOT of data on when these melt events occurred, here is a graph of them over the last 6000~ years. Note how rare theyare in the last few centuries, certainly none in the 1930s or 40s.
http://www.gisp2.sr.unh.edu/DATA/alley1.html
Note how they have been related to the increased summer sun in the past with a summer perihelion, but the rising CO2 is causing a similar rise in downwelling energy which, by the indirect means of altering the jet streams, has caused more surface melting.

Phil.
June 18, 2013 4:37 am

David says:
June 17, 2013 at 9:18 pm
Phil. says:
June 17, 2013 at 4:49 pm
“The next five-10 years will reveal whether or not 2012 was a rare event resulting from the natural variability of the NAO or part of an emerging pattern of new extreme high melt years.”
This year is shaping up similarly so it will be interesting to see how it plays out.
===============================================
Is a plus one million sq K of sea ice similar. For how many minutes did some 97 percent of Greenland Ice melt?

Check out the mass balance graph here.
http://beta.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

izen
June 18, 2013 4:47 am

@- Bruce Cobb
“Show your work.”
With pleasure.
http://onlinelibrary.wiley.com/doi/10.1002/grl.50382/abstract
“Here we present the time evolution of the global ocean heat content for 1958 through 2009 from a new observation-based reanalysis of the ocean. Volcanic eruptions and El Niño events are identified as sharp cooling events punctuating a long-term ocean warming trend, while heating continues during the recent upper-ocean-warming hiatus, but the heat is absorbed in the deeper ocean. In the last decade, about 30% of the warming has occurred below 700 m, contributing significantly to an acceleration of the warming trend. ”
http://www.livescience.com/29222-climate-change-extreme-weather-report.html
“Americans are continuing to connect the dots between climate change and extreme weather in the United States,” said Anthony Leiserowitz, director of the Yale Project on Climate Change Communication. “They’re associating climate change with some of the major events that we experienced last year, like the ongoing drought.”
And of course they are right.
http://woods.stanford.edu/news-events/news/global-warming-and-extreme-weather-events
More than two dozen leading scientists convened to evaluate the abundance and quality of available records of heat waves, cold waves, floods and droughts in the United States. They determined there are enough reliable data for each of those four phenomena for researchers to make reliable evaluations of whether the likelihood of those events has changed over time.

KNR
June 18, 2013 5:02 am

No problem , clearly the ‘magic ‘ of AGW, is there anything it cannot control, means its affecting the jet stream in ‘some way, which in turn has lead to melting . See its all CO2 after all.

Gary Pearse
June 18, 2013 6:02 am

“…and probably unlikely to have occurred previously for well over a century….”
Empty, chatty. Surely every statement in a scientific study should be necessary and supported. They are geographers, though, a soft science discipline that studies maps and words and has no need of mathematics. This outmoded field belongs with alchemy. This another Me-too paper.
.

Ian W
June 18, 2013 6:54 am

joerommiswrong says:
June 17, 2013 at 3:57 pm
“…probably unlikely to have occurred previously for well over a century”
Pure supposition.
That’s not science, it’s just b*llsh*t

See http://www.drroyspencer.com/2013/06/who-dares-to-deny-arctic-warming/

rgbatduke
June 18, 2013 7:12 am

here’s the headline over at ThinkClimate. “Exceptional 2012 Greenland Ice Melt Caused By Jet Stream Changes That May Be Driven By Global Warming”
…And how are you gonna argue with that! After all, it is true! It also may have been caused by jet stream changes caused by a Brazillian Butterfly beating its wings fifteen years earlier. It may have been caused by Global Cooling (since, on average, that is what we are experiencing although it is a marginal effect not really distinguishable from zero within any reasonable estimate of noise). It may have been caused by space alien intervention as they seek to protect their secret bases buried in the icepack in Antarctica and Greenland. It may have been the will of God that Greenland’s surface should briefly melt.
Or it could have been caused by a blocking high that more or less randomly happened, and event that was nucleate out of an absolute sea of pressure fluctuations that happened to encounter conditions favorable for growth and happened to move to a place that diverted the Jet Stream. Blocking highs happen. I’m sure a weather person like Anthony knows how frequently they happen, that is, what the probability is of developing a blocking high in any given year. I do recall that a few years back — not 2012, maybe 2009 or 2010 — there was a blocking high that sat out in the middle atlantic for months. I noticed because I pay attention to atlantic circulation, temperature and pressure in hurricane season, living pretty much on top of one of the pins at the end of the west-africa to southeast-us bowling alley, where tropical waves nucleate, grow, and spin (usually) west by north west until they either decide to arc sharply north and spin out harmlessly over the colder mid-atlantic (the fate of I’d guess over 1/2 of the tropical storms so nucleated) or line up on Cuba, Florida, North Carolina and deliver a punch. Blocking highs significantly alter the probable tracks and nucleation chances.
I once upon a time spent a harmless year or two studying/simulating two dimensional ferromagnets. The statistical mechanics of 2d ferromagnets is really quite interesting because 2d is a critical dimension where certain kinds of interaction permit phase transitions and others do not. It is also interesting because “rotational” structures emerge, the ordering of spins around a defect into a vortex. Spin vortices can actually organize and form quasi-particles that interact — collide, scatter, join together, anihillate — much like eddies or turbulent rolls in fluid systems that have self-organized around a long dimension. I also spent a bit of time learning about spin glasses — systems that break ergodicity and develop very, very long lived local equilibria that are generally not the true equilibrium state (the one that minimizes the free energy). The latter exhibit what one of my mentors, Dr. Richard Palmer, dubbed “frustration” — the inability of the system to reach equilibrium as in lower its free energy because to reach it it had to destroy locally stable spin configurations in such a way that it RAISED the free energy. The phase space for systems like this is “rough” with a nearly fractal distribution of local equilibria and barriers, and one has to go up first in order to go down from nearly anywhere in it.
Lessons learned from this sort of system influenced the development of a variety of computational optimization techniques used in systems that (ultimately) bear little resemblance to actual spin systems except in the sense that they have enormous phase spaces and the function being optimized is “rough”, or “complex”, so that traditional gradient search methods fail badly by going to the nearest mimimum (which might well still take a huge amount of time as that minimum might lie at the end of a tortuous valley, hence the development of conjugate gradient methods that attempt to efficiently follow the valley floor instead of bouncing back and forth across its walls). Simulated annealing, for example, lets such a systems spend a lot of time near the peaks and then slowly causes it to descend, hoping it will get trapped in at least a “good” deep valley if not “the” deep valley that contains the true minimum (where one can optimize either way, but in analogy with free energy I think minimum even when maximizing something:-).
Two other methods used to search such spaces include Monte Carlo — which basically amounts to rolling dice to generate coordinates in the space and then determining their depth to search for a place that is deeper than others (and perhaps finishing with a conjugate gradient search in the best valley MC can turn up) and genetic optimization. Genetic optimization is actually pretty amazing. It is far more efficient at searching high dimensional spaces than pretty much anything except importance sampling MC, which gets to exploit a directed Markov process (and which still experiences complexity issues and the divergences of equilibration times near critical points) and event that works most efficiently when it is possible to formulate global MC moves — cluster moves — in the Markov process that break up non-equilibrium “false” order on all length scales and not just locally.
The point of all of this is: Most of these problems are mirrored in climate dynamics, both at a fine-grained resolution with local interactions and when considering the large scale evolution of collective structures that interact according to quasiparticle rules that are not immediately obviously linked to the microscopic physics in the nonlinear Navier-Stokes PDEs. A blocking high is a perfect example of a macroscopic structure that would likely be “invisible” to a microscopic first-principles model — the model might generate them, but it doesn’t actually use rules for their time evolution as a distinct discrete entity. Similarly, macroscopic models might well do fine at describing the time evolution of high and low pressure systems according to semi-empirical rules, but might well lack the ability to predict the time evolution of the structures themselves from butterfly wingbeats and because they linearize around semi-empirical rules that work now for a collective macroscopic state, they are quite helpless if the system chaotically switches to a different mode/attractor that can do things such as completely change heating/cooling efficiency on arbitrarily large scales. These switchings are actually readily visible in ordinary turbulence — they are the reason golf balls are pebbled instead of smooth, and one of the reasons physicians listen to your arteries with a stethoscope. If anything, the kinds of quasiparticle structures and patterns that can transiently emerge and interact with “rules” that work for a while is staggeringly large in fluid systems compared to what goes on in comparatively simple systems such as 2D ferromagnets or 3D ferromagnets or spin glasses (where spin glasses are complex but still simple compared to turbulent flow in even the easiest toy systems).
There are numerous known/named cases of self-organization of convective structures in the earth’s atmosphere. One of the prettiest is convective rolls, or “cloud streets” — phenomena that frequently occur in a confined fluid heated at the bottom and cooled at the top, but simple thunderstorms are a self-organized convective structure, hurricanes are much larger self-organized convective structures, high and low pressure systems are in the first place self-organized structures that often have convective features.
To claim that any science at all is even capable of suggesting that one such observed feature is — perhaps — caused by GW is absurd. It is a lie. It is an abuse of accepted discourse in science. The observed melt was — perhaps — caused by the farts of invisible pink unicorns that populate the landscape and eat invisible pink beans. Falsify that! Perhaps — Jimmy Hoffa was abducted by space aliens. Prove that it isn’t true!
It is raining outside right now where I live. Rain, of course, happens. It has happened with some probability from the time that water vapor first was cooled to the point where it could nucleate and fall out of the primordial atmosphere to form the oceans. Nevertheless, the fact that it is raining right now, in the particular circulation pattern that is dominant right now, — perhaps is due to global warming. Who can argue with that?
Besides, it is true. Thirty thousand years ago, it might have been snowing outside, not raining. But it got warmer! The snow melted. The icepack that buried the northern half of North America kilometers deep melted. Some fraction of the molecules in every raindrop that falls was bound up as ice, and would not have been able to fall on the just and unjust alike if it were not for the fact that the Earth warmed up in the Holocene and remains warm today. It is also undeniable that the Earth has warmed since the LIA and that this warming, too, at least influenced the probability of rain, and empirically given that the worst proxy and human recorded droughts in recorded history in NC, at least, occurred during the LIA the chances of rain probably increased as the Earth warmed.
Of course, more locally it has cooled. This summer as previously noted has been rather cool (at least here) compared to most of the summers over the last few decades — lots of cool, high pressure days with winds blowing down from Canada. The globe itself is effectively neutral. That makes it more difficult to claim that an event is caused by warming, because you have to specify which warming. The warming from the 1997/1998 El Nino? Is that causing the rain outside? Did that cause the blocking high and hence the ice melt? Really? And you know this how?
rgb

izen
June 18, 2013 7:32 am

Its very odd… Less than twenty posts in is a video in which the leading scientists researching this subject gives a detailed description of what the jet stream is, how it works and why it is now meandering about and causing extreme weather.
And yet several posters have expressed dismay that we do not know what the cause of the Greenland melt or the varience of the jet stream might be.
Are people projecting their own ignorance?! Science seems to know far more than many here givve it credit for. It is always wise to put any terms in a post like this into an acedemic search engine and find out what peer reviewed papers have been written on the subject otherwise the lack of knowledge you decry might actually be your own.

beng
June 18, 2013 7:44 am

Where did all that surface “melt” go last summer? Snow isn’t like rock, so it prb’ly soaked into the snow and — refroze. Ooowww, so scary…..

highflight56433
June 18, 2013 8:28 am

Duh! Is there a weather map that did not show the blocking high described in this come lately paper??? 🙂

Colin
June 18, 2013 8:34 am

And the newspaper articles about this should start any day now. I can just see the headlines – “We TookTheir Word for it but Didn’t Verify It. Silly Us”. Do I need the sarc? Didn’t think so.

Keitho
Editor
June 18, 2013 8:58 am

In the meantime the temperature in the Arctic is the coldest it has been for today in 21 years.
http://ocean.dmi.dk/arctic/meant80n.uk.php . . the last time was in 1992 . .
http://ocean.dmi.dk/arctic/meant80n.uk.php

Kaboom
June 18, 2013 10:21 am

Very little of that meltwater made it to the sea as the episode was very short lived and not penetrating in a meaningful manner. Most of the melt quite likely re-froze within seconds to minutes from the cold of the underlying ice mass.

Theo Goodwin
June 18, 2013 10:43 am

izen says:
June 18, 2013 at 7:32 am
“And yet several posters have expressed dismay that we do not know what the cause of the Greenland melt or the varience of the jet stream might be. Are people projecting their own ignorance?!”
My post might have been a bit brief. But rgbatduke set forth the problem of attribution in great detail. I await your response to him.

Theo Goodwin
June 18, 2013 10:51 am

izen says:
June 18, 2013 at 1:39 am
“Ascribing something to a unusual, but ‘natural’ variation is NOT an explanation, just a description. It begs the question; Why does this unusual natural variation happen, what are its causes.”
You commit what all oxford graduates know as a “Category Mistake.” Natural Variation is not a cause or a set of causes but an entirely different sort of thing. It is the range of our data from lowest to highest. For example, Mann’s attempt to “eliminate” the Medieval Warm Period was an attempt to erase an important high point in our temperature data. Mann’s attempt did not address putative causes of MWP.

Theo Goodwin
June 18, 2013 10:54 am

Forgive me. Oxford.

george e. smith
June 18, 2013 11:35 am

“””””…..izen says:
June 18, 2013 at 4:31 am
@- Billy Liar
“When sufficient firn cores have been taken over the rest of the area of Greenland we’ll have some data.”
We already have a LOT of data on when these melt events occurred, here is a graph of them over the last 6000~ years. Note how rare they are in the last few centuries, certainly none in the 1930s or 40s.
http://www.gisp2.sr.unh.edu/DATA/alley1.html
Note how they have been related to the increased summer sun in the past with a summer perihelion, but the rising CO2 is causing a similar rise in down welling energy which, by the indirect means of altering the jet streams, has caused more surface melting……”””””
As far as I know, the melting of ice, has been directly linked to one physical phenomenon. That is the raising of the Temperature of that ice to around 273.15 Kelvins, give or take some small adjustments due to the ambient pressure, which for the ice surface, would be the atmospheric pressure, no doubt reduced from standard by the typical altitude of Greenland ice surfaces; accompanied by the input to that ice surface of a supply of energy, perhaps as “heat energy” which must (second law) come from some HOTTER material source above (or below) the ice surface. Well in the case of ice, the below surface must necessarily be COLDER, so nyet on that supplying latent heat of melting (80 calories per gram of ice). So that leaves a warmer atmosphere above for that source of “heat energy”; or that energy required for the phase change, could be supplied by EM radiation from some overhead atmospheric source.
Since photons know nothing of Temperature, then the source of that downward radiation from the atmosphere, could be either hotter or colder than the ice surface.
Now the ice surface itself is a source of thermal (black body like) EM radiation, and since we are postulating that the surface is melting, then we can presume that the effective BB Temperature of that radiation, is about 273 Kelvins, about 15 deg. C lower than the global mean Temperature of about 288 Kelvins, so the thermal emission must be less than about 315 W/m^2, appropriate for a 273 K BB radiator, and the spectral peak would be about 10.65 microns wavelength, from Wien’s law.
Now if the overlying atmosphere is HOTTER than the ice surface near 273K which it must be to supply “heat energy”, then it would be emitting a thermal radiation spectrum, but it would be far less intense than the 10.65 micron peak spectrum from the ice surface, since the atmosphere molecular density, is a tiny fraction of that of ice. So very little melting could be due to LWIR thermal radiation from the atmosphere. Then there is the re-emitted greenhouse effect radiation from the CO2, and also from atmospheric water vapor, which is likely to still be more abundant, than the CO2. But that re-emitted greenhouse radiation, originally came from the thermal emissions from the ice itself, and it would be only of the order of half of the surface emission, that is in the CO2 band (or water), since the GHG emission, is necessarily isotropic, so only half can be coming back down to the ice.
So that leaves the ice as necessarily, a net EMITTER of LWIR EM radiation, only a fraction of which is CO2 active, and only half of that can come back down.
Hence, there simply is no way that the atmosphere, and GHG effects can be supplying “latent heat energy” to the ice, to melt it; in excess of the thermal emission of LWIR EM radiation by the ice.
Now Greenland ice is quite thick and at some altitude, but I don’t see how it could possibly be in contact with jet stream air flows.
The only other possible source to provide “latent heat energy” to the ice, in order to melt it at about 273 Kelvins, is the sun itself, in the form of shorter wave solar spectrum radiation, which contains near IR wavelengths that are absorbed in H2O. H2O is most strongly absorbing at 3.0 microns, and only 1% of solar spectrum radiant energy remains at longer than 4.0 microns.
I’m left with an inescapable conclusion that only the sun can melt the Greenland ice surface, and I don’t see where jet streams come into play, unless to move cloud into or out of the picture.
Well maybe I’m missing something; my computer is far too slow to do terra-flop modeling.

June 18, 2013 12:30 pm

Ian W
Thanks for the link. Superb stuff!
I can roll it out whenever some rabid warmist tries to tell me today’s melt is “unprecedented!” (wail, gnash teeth)
BTW I think you may be in danger of making izen rather hot-tempered 😉

June 18, 2013 12:36 pm

Izen,
When I was scuba-diving off the coast of Western Scotland this Easter, I went looking for your ‘hidden ocean heat’ as I could have done with a bit of it. Couldn’t seem to find it though. Brrr!
(yes, I know my comment is rather fatuous, but I can’t help but laugh at rabid warmists like ol’ izen)

Tim Clark
June 18, 2013 2:13 pm

{ izen says:
“Americans are continuing to connect the dots between climate change and extreme weather in the United States,” said Anthony Leiserowitz, director of the Yale Project on Climate Change Communication. “They’re associating climate change with some of the major events that we experienced last year, like the ongoing drought.”
And of course they are right. }
Yeah, those Obama supporters are one intelligent bunch.

Janice Moore
June 18, 2013 2:26 pm

“CO2 is causing… ” [Izen at 4:31AM today]
Prove it.
No, Izen, I didn’t ask you to jump up, grab three tennis balls, and start juggling and telling jokes. Waving your hands wildly while you flounce from one side of the stage to the other won’t work, either. What do you think this place is, A CIRCUS?
Now, if you choose to throw one of your famous fits — THAT would be entertaining.
Can’t seem to work one up? Okay. I’ll help you. What is the matter with you, Izen? Are you crazy? You must be. No sane person would tell lies that made her or him look as RIDICULOUS as you are making yourself appear. Oh, I beg your pardon, you aren’t lying or insane, you’re just stupid and prideful? Well, in that case, I’m sorry — NOT! If you know that you are stupid, then you know enough to NOT POST AS IF YOU KNOW SOMETHING WORTH SAYING.
Bwah, ha, ha, ha, ha, ha, ha, haaaaaaaaaaa!
[Okay, okay, qualification — IF Izen is insane, then his or her spending his or her psychotic breaks posting on WUWT is not a laughing matter. Get help, Izen. You don’t need to do this to yourself.]
**********************************
Izen [1:46AM today]: “increasing energy which is mainly going into the oceans. The evidence for that is unequivocal and robust”
Bruce Cobb [4:23AM today]: Show your work.
Izen [4:47AM today – Izen’s “proof” for Cobb]:
1) “observation-based reanalysis of the ocean” [i.e., recycled model output “data,” a.k.a. “JUNK”];
2) “Americans are continuing to connect the dots” [whoo, hoo, that’s “robust” proof]
3) “two dozen leading scientists convened to evaluate the abundance and quality of available records of heat waves, cold waves, floods and droughts in the United States.” [no CAUSATION mechanism mentioned at all]
JM: So, Izen, you just ran really fast in the hamster wheel for — NOTHING.

Janice Moore
June 18, 2013 2:36 pm

Okay, okay, O Wonderful WUWT Scientists, I realize this is a science forum. LOL, you probably wonder if I am sane! Hmm. Not sure. #[%)] I’ll try to stop harassing the Izen…………. for now (heh, heh, heh).
…… but, provoking the Izens of the world is SO MUCH FUN!!!
Love this site.

Spence_UK
June 18, 2013 3:35 pm

Izen says:
“Its very odd… Less than twenty posts in is a video in which the leading scientists researching this subject gives a detailed description of what the jet stream is, how it works and why it is now meandering about and causing extreme weather.”
No, it’s not odd, and we know what the jet stream is. I’m not sure you do though, because if you did you would never say: “why it is now meandering about…” – it has always meandered izen, this isn’t a new phenomenon. The jet stream is a product of atmospheric turbulent dynamics. Turbulent dynamics, as described by Andrey Kolmogorov some seventy years ago, exhibits behaviour that results in low frequency variations dominating the behaviour of the process at all scales. This low frequency characteristic is often misinterpreted as some kind of causal behaviour, but such analysis amounts to the same kind of post hoc ergo propter hoc error that water diviners use to explain their “successes”.
The video showing an individual playing “pin the extreme weather tail on the climate change donkey” is amusing, but that “causal relationship” will break down in years to come, by which time the climate alarmists will have some other hand-waving explanation for why their previous prediction failed.
“And yet several posters have expressed dismay that we do not know what the cause of the Greenland melt or the varience of the jet stream might be.”
I know exactly what the *variance* is caused by, and have explained it simply and clearly. And given the importance of *variance* (as the square of the standard deviation) I don’t think I’ve ever come across a scientist who didn’t know how to spell it. But for now, I will give you the benefit of the doubt – English may not be your first language – but I suggest you read up a little on Kolmogorov’s work, you cannot understand the nature of the jet stream without it.

milodonharlani
June 18, 2013 5:56 pm

jai mitchell says:
June 17, 2013 at 4:09 pm
Myron Mesecke
Yes, that is basically what they are saying. A blocking pattern left a dome of high pressure over Greenland causing unprecedented melt. In the summary of the article it says, ”
————————
It was not unprecedented. It happens with regular frequency.

Phil.
June 18, 2013 6:06 pm

beng says:
June 18, 2013 at 7:44 am
Where did all that surface “melt” go last summer? Snow isn’t like rock, so it prb’ly soaked into the snow and — refroze. Ooowww, so scary…..

Yes it soaked into the snow but didn’t completely refreeze.
http://nsidc.org/greenland-today/2013/03/an-early-spring-calibration-for-melt-detection/

izen
June 19, 2013 1:29 am

@- Janice Moore
“Now, if you choose to throw one of your famous fits — THAT would be entertaining.
Can’t seem to work one up? Okay. I’ll help you. What is the matter with you, Izen? Are you crazy? You must be. No sane person would tell lies that made her or him look as RIDICULOUS as you are making yourself appear. Oh, I beg your pardon, you aren’t lying or insane, you’re just stupid and prideful? Well, in that case, I’m sorry — NOT! If you know that you are stupid, then you know enough to NOT POST AS IF YOU KNOW SOMETHING WORTH SAYING.”
I am quite used to being told what I think about a subject by people convinced I ‘believe’ in Cagw and am anti nuclear power, which is always gratifying as it enables me to avoid all that hard work and deciding what I think myself.
However it is a new experience to be told how I should behave, based apparently on past actions which I must admit I cannot remember ever having done.
I did not realise that I am ‘famous’ for my ‘fits’, I thought the most egregious thing I have done at WUWT was being impolite to Richard Courtney by suggesting I would always think of him by his diminutive after he ridiculed my name.
However your accusation that I lack the knowledge to contribute meaningfully to this debate and I am merely exhibiting an example of the Dunning-Kruger effect may be better founded. Very few posters here are published Earth system scientists and the tendency to opine about matter far above our pay grade seems to be the sine qua non of WUWT.
Obviously I accept the science that is also endorsed by 97% of the literature, many here do not. May I ask what evidence would convince you to at least consider that the mainstream human understanding of the climate is largely accurate?
I am happy to explain what data or findings would cause be to have serious doubts about the current explanations of the observed warming, melting ice and ocean heat content rise.

Spence_UK
June 19, 2013 6:01 am

Izen, I take it you have not yet read Kolmogorov’s work? Your words are scientifically meaningless. Take this for instance:
“Obviously I accept the science that is also endorsed by 97% of the literature”
What does this even mean? What is “the science”? Kolmogorov’s work is clearly part of “the science” yet you seem unwilling to accept that. And what is “the literature”? You mean the scientific literature? Which covers a massive range of subjects – I can assure you 99.9999% of the totality of scientific literature makes no reference whatsoever to what you are talking about, so clearly 97% cannot endorse it.
Furthermore consensus has never been a cornerstone of science – Lysenko managed to get far better than 97% of the Russian scientific literature supporting his view and rejecting the entire field of genetics. So what?
Your commentary here is vague, incoherent, flawed and, most importantly, unscientific. Was that your goal?

izen
June 20, 2013 3:02 am

@- .Spence_UK
Izen, I take it you have not yet read Kolmogorov’s work?
No. Do you have a link? The only reference I can find is to a couple of books by a A N Kolmogorov on minimum energy solutions in computer vision systems.
@- “What does this even mean? What is “the science”? Kolmogorov’s work is clearly part of “the science” yet you seem unwilling to accept that. And what is “the literature”? You mean the scientific literature? ”
I think it is obvious from the context, I mention Earth systems science, that the scientific literature I am referencing is that on the physics of the surface conditions of planetary bodies. So the science of how we understand the various conditions on Venus, Mars, the moon and of course the Earth. The fact that no published paper on this subject appears on a search for Kolmogorov makes me doubt he is exactly mainstream….
@-“Your commentary here is vague, incoherent, flawed and, most importantly, unscientific. Was that your goal?”
Perhaps I was shaping my posts to be consistent with the common form here…{grin}
But I am happy to be more precise and give links to the published research if you ask.
By the way can you answer the question I put previously, can you detail what evidence would cause you to doubt your present POV and consider the mainstream scientific explanation of the present observed climate changes as correct?
I agree that the consensus does not validate the science, but the consensus is a measure of the strength and consilience of the present science.

Spence_UK
June 20, 2013 6:40 am

“No. Do you have a link? The only reference I can find is to a couple of books by a A N Kolmogorov on minimum energy solutions in computer vision systems.”
Well, it’s the same guy, but he is a little better known for his earlier work, such as defining the axioms upon which the modern formalisation of probability theory is based, and developed theories of turbulent flow which still underpin analysis of turbulence in fluids today. He is perhaps one of the top 20 most influential scientists of the 20th century… and you’ve never heard of him. Wow.
“I think it is obvious from the context, I mention Earth systems science”
Firstly, if you mean Earth systems science, say so, do not refer to it as “the science”, it is vague and inaccurate. Secondly, even within earth systems science, the vast majority of the literature takes no position on this topic.
“The fact that no published paper on this subject appears on a search for Kolmogorov makes me doubt he is exactly mainstream….”
You want to study a system involving turbulent dynamic fluids and you don’t think Kolmogorov is “mainstream” enough. Ummm… okay.
“By the way can you answer the question I put previously, can you detail what evidence would cause you to doubt your present POV and consider the mainstream scientific explanation of the present observed climate changes as correct?”
I can’t answer this question scientifically because it is not posed as a scientific question. Which points of view? Which bits of mainstream climate science? Some published literature in climate science is very good. Some of it is terrible.
We can talk about specifics, and we have already done so. The jet stream is a great example. The analysis above fails to account for the stochastics in the jet stream that arise from the turbulent dynamics of the atmosphere. These define the bounds of natural variability of the jet stream. It is immediately obvious that they have not been accounted for correctly in the analysis, for example, in the video above.
This is really basic stuff. In science, your measurements and analysis are always limited by something. If you have not understood and accounted for these limits, then your analysis is scientifically worthless.