« New NASA videos | Main | PIOMAS October 2014 »

Comments

Feed You can follow this conversation by subscribing to the comment feed for this post.

mark

sorry Neven before I am corrected I meant not present for 800,000 years

Neven

I don't mind genuine skepticism one bit, mark.

Colorado Bob

Arctic sea ice helps remove carbon dioxide from atmosphere, study shows

Only recently scientists have realized that sea ice has an impact on the planet’s CO2 balance.

“We have long known that Earth’s oceans are able to absorb huge amounts of CO2. But we also thought that this did not apply to ocean areas covered by ice, because the ice was considered impenetrable. However, this is not true: New research shows that sea ice in the Arctic draws large amounts of CO2 from the atmosphere into the ocean,” says Dorte Haubjerg Søgaard.

Dorte Haubjerg Søgaard has just completed her studies of sea ice in Greenland. The studies show that sea ice may have a major impact on the global carbon cycle, and that chemical processes have a much greater impact on the sea ice’s ability to remove CO2 than biological processes. The research is published as a series of articles in scientific journals.

“The chemical removal of CO2 in sea ice occurs in two phases. First crystals of calcium carbonate are formed in sea ice in winter. During this formation CO2 splits off and is dissolved in a heavy cold brine, which gets squeezed out of the ice and sinks into the deeper parts of the ocean. Calcium carbonate cannot move as freely as CO2 and therefore it stays in the sea ice. In summer, when the sea ice melts, calcium carbonate dissolves, and CO2 is needed for this process. Thus, CO2 gets drawn from the atmosphere into the ocean — and therefore CO2 gets removed from the atmosphere,” explains Dorte Haubjerg Søgaard.

The biological removal of CO2 is done by algae binding of carbon in organic material.

http://www.sciencedaily.com/releases/2014/09/140922110424.htm

Colorado Bob

These feedback loops we are learning about that are happening in the Arctic make me sick .

Charles Longway

Vsaluki, Mark, and others new to Neven’s ASIB. Welcome, you have come to the right place. I do, however, need to warn you that you are in danger of becoming like me. And yes I am an ‘old white man’. I am also a Christian, Republican, and Texan. After reading this blog for over 3 years I have joined: Neven, 97% of scientist, and 100% of the leaders of the 5 most popular religious faiths in the conviction that we are causing climate change and that, if we do not change our life style, future generations will suffer horribly for our actions.
So here is your danger. If you continue to read the blog you will come to see the shallowness of arguments from the likes of WUWT. You will also likely feel a moral obligation to change your life style as I have. Since I stumbled onto Neven’s blog I have spent over 100K to get my family on to renewable energy: solar panels, 2 Chevy Volts, better insulation, new air conditioner, and new windows. My investments will pay off, perhaps even in 5 years, and after that my family will be better off. So perhaps I have over hyped the danger of the blog - certainly less then the danger of ignorance.
I only comment a few times a year, but do hope that you will continue with us. Perhaps I can give a word of encouragement more often. Looking forward to your thoughts.

wayne

Well done Charles, you will not only recover your investments but get wealthier in the long tun. May you be the envy of the neighborhood! Live long in clear blue wild west air and prosper.

Would like to read more about Wadhams latest data . .8 meter average sea ice contrasts with Piomas. I am not a fan of Piomas, but will not largely discredit its info without strong evidence to the contrary.

Colorado Bob

Charles Longway |

Welcome to the party.

Colorado Bob

John Christensen | September 22, 2014 at 10:50

John I love your work , but you miss the point .
The good doctor measured the sea ice in 1976 , it was over 16 feet thick , They had him on the Oden this year, and I trust his comment that it was about 30 inches.

I trust that a man from the oldest seat of science can measure things.

So when he reports the sea ice when from 16 feet to less than 3 feet , I don't split hairs about the numbers at the bottom.

Jai Mitchell

You know mark, if you spent some actual time reviewing the science you wouldn't sound so uninformed. Saying things like, medieval warming was 1 degree warmer than today is so far away from what the actual science says that you just seem ignorant and/or deceived.

Here, this is a website that you might like to start using http://www.scholar.google.com

Here is the graphic you need to check out

http://www.climatechange2013.org/images/figures/WGI_AR5_Fig5-7.jpg

Here is the working group I paper, http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-12Doc2b_FinalDraft_Chapter05.pdf
look up image 5.7 and start reviewing the papers listed as references to see how much time and effort has been put into reconstructing past temperatures and realize how glibly you repeat falsehoods that are stated to defend an ideological position vs. a scientific one.

Gideon Low

Mark: You are not who you present yourself to be. At the risk of just a bit more diversion from the real topic, I want to make this clear to all readers present and future. Some of your quotes:

"I dont (sic) comment technically as I have no new info, and bow to the greater knowledge of others"

The default position for any scientifically minded person that is a professed amateur and relatively new to a topic of conversation is quite sensibly to accept the overwhelming scientific consensus of acknowledged experts on the topic as their starting point. Here you present yourself as such a person, but then almost immediately contradict yourself. You then even chastise others--in the cause of promoting civility, for using terms like "fake skeptic" and "denier". You even go out of your way to complement the work of this blog. But, when we read-on further, it becomes clear from your language and that this is a ploy to be allowed to present (at best) conjecture as fact.

"there is still a missing link that has scientists hypothesising (sic) in both camps but still unable to prove theory by events"

This is of course a very loaded statement. Here you try to establish a false equivalency with the statement "scientists in both camps". There is only One scientific "camp" on the (historically speaking) incredibly fast shrinking Arctic sea ice. The only place where there are Two "camps" is where politically/financially motivated or otherwise attention seeking charlatans repeat discredited "theories" ad nauseum in order to confuse the public. Scientific hypotheses wrt AGW have absolutely been confirmed by rigorous observation to the point where they are currently accepted as scientific fact.

"I have no idea what is going to happen and I really dont (sic) think anybody else does either"

After first professing modesty and difference to those with "greater knowledge", you now completely contradict yourself, professing enough knowledge to confidently imply that scientific experts have "no idea". This is VERY passive aggressive.

"As the increase in temperature worldwide is generally measured in annual increments of fractions of degrees . . . This has to be weather based rather than climate based."

After claiming to be a person humbly seeking information, all of a sudden you're making bold claims about what "has to be" wrt weather and climate. Worse these bold claims (as others pointed out) actually expose how little you know about the agreed-upon facts on the effects of global warming on different latitudes (or, perhaps you know, but are intentionally ignoring them).

"I am not in any camp here and I would resent being categorised (sic) in any of them. It continues to surprise me the strength of opinion that so desperately wants to prove that the ice will disappear in the summer and never recover. I personally think it will but then will recover, but thats a personal hypothesis that has no more proof in fact than any one elses (sic)."

Here, again, you imply Two (presumably equal) "camps" when there is no such thing. You then chastise other contributors for their "strength of opinion", and even call them "desperate" and imply a personal crusade motivation of some sort. You're again deliberately confusing political "camps" with scientific ones, when in fact only One (and overwhelming at that) scientific consensus exists.

I find your rhetorical contradictions and only vaguely cloaked attempts to call attention to yourself through provocative statements just as unfortunate, sad, and misplaced as the activities of the more obvious trolls. I'm not fooled, I doubt any of our regular readers are, and I sincerely hope that any new or casual readers also see right through you.

To the moderator: If this goes to far, please do remove it. I would completely understand.

mark

Jai your stance does not actually match the historical record of crops grown (Vines from Italy grown on the scottish border) and clothing worn by romans and other people during this time nor the ability of vikings to explore 'greenland' and further afield. I appreciate your references as I am always an avid reader, but I treat all interpolations of data such as this with a degree of scepticism as anyone should. So I am prepared to accept that there are different views of the Medieval optimum but please have the decency to allow me to express a personal opinion founded on my understanding of the facts even if your opinion and 97% of scientists dont agree - it doesnt necessarily make you right and me wrong - the odds are just not in my favour perhaps. Without scepticism and alternative opinion there is no debate and no science.

I thoroughly resent your use of the words 'ignorant', 'glibly' and 'falsehoods'. Misinformed I may be but that is harsh as well. I dont know why you have selected me for this degree of trolling - I am engaging with a site I enjoy and trust - what harm am I doing to any conversation here.

Neven

Mark, spreading misinformation-myths, whether consciously or not, is doing harm, because you might confuse people on a potentially serious issue. It's especially harmful, and perhaps disingenuous, when people take the time to (mostly) politely show you why your statements are wrong, and you then repeat what you have already said in a slightly different shape (the wine in the UK meme, for instance).

It'd be a shame if Gideon Low is right in his assessment of your posting behaviour so far in this thread. To remove any doubt, I would appreciate it if you refrain from regurgitating debunked fake skeptic disinformation, while excusing yourself that you don't know exactly and your opinion is as good as anyone's on scientific subjects. Thanks.

Neven
(Vines from Italy grown on the scottish border)

Almost 10 (!) years ago this was written on the RealClimate blog:

Since a commenter mentioned the medieval vineyards in England, I’ve been engaged on a quixotic quest to discover the truth about the oft-cited, but seldom thought through, claim that the existence of said vineyards a thousand years ago implies that a ‘Medieval Warm Period‘ was obviously warmer than the current climate (and by implication that human-caused global warming is not occuring). This claim comes up pretty frequently, and examples come from many of the usual suspects e.g. Singer (2005), and Baliunas (in 2003). The basic idea is that i) vineyards are a good proxy for temperature, ii) there were vineyards in England in medieval times, iii) everyone knows you don’t get English wine these days, iv) therefore England was warmer back then, and v) therefore increasing greenhouse gases have no radiative effect. I’ll examine each of these propositions in turn (but I’ll admit the logic of the last step escapes me). I’ll use two principle sources, the excellent (and cheap) “Winelands of Britain” by geologist Richard C. Selley and the website of the English Wine Producers. - See more at: http://www.realclimate.org/index.php/archives/2006/07/medieval-warmth-and-english-wine/#sthash.UBJdLins.dpuf

Anyone interested might want to read the entire blog post.

mark

*snip*

I accept I am in a minority in that i neither accept or reject this *snip* scientific staus quo. I am a scientist - my expertise is in agriculture and amenity horticulture and I have many a debate with my peers about how more natural and environmentally sound practises can be used to grow crops and grass - I would digress further but I am sure I would annoy Neven and I respect him and his site above all others!!

*snip*

As Jai before you I find your trolling attitude insulting in the extreme. If I wish to make a statement then by all means disagree with me and if needs be post your reasons dont be so completely presumptious of my motives which I can tell you are completely benign - I reserve the right to reply as I feel fit and I trust and believe Neven will redact my comments if he thinks I overstep the line, the way I think is not up to you to castigate.

Enough of this - your attitude towards me will be applauded by some on here I am sure. Please Neven do not 'snip' his comments, but I am now completely insulted and bored *snip*

[Redacted a bit; N.]

Neven

Mark, you might be doing it subconsciously because you have just started following the AGW debate, but you are displaying classic troll behaviour: first spread disinformation and then act indignantly when someone makes this clear in not so nice terms (it's the Internet, keep your pants on), interspersed with further classic fake skeptic memes.

Let's leave it at this.

John Christensen

Hi Colorado Bob,

Thank you for your comment.

And yes; I am sure he is very capable of measuring and do not doubt the numbers. We know volume is decreasing faster than area or extent, which affirms his measurements.

It is the generalization and conclusion he makes, which does not appear to be scientifically based - unless he is just stating that the 0.8 meters of ice in his area of measurement could melt away in one to two years, which is certainly possible, agreed.

If he did refer to the Arctic as a whole and state it is possible for the Arctic sea ice to melt away in less than two years, then he needs to substantiate the argument, as this is an extreme standpoint, to say the least.

John Christensen

Hi mark,

Being on the overall skeptical side of matters myself and recognizing the way scientific paradigms limit the perspectives even of scientists, as well as being ever hopeful/optimistic on behalf of the resilience of Arctic sea ice, I need to agree with others here that it is of little value to point to the state of the climate a thousand years ago, or otherwise at the high level to question what is happening.

This blog is focused on Arctic Sea Ice, and being just this, it is extremely valuable from my perspective, to try and understand the nature and weight of the different factors impacting Arctic sea ice. This will increase our knowledge and improve estimations of what will happen in the next 5, 10 and 50 years, both to the ice and the World we live in.

Being further along on the skeptical line, you should have a close look at PIOMAS data, look at the graphs, download the daily volume readings, check interyear changes, etc., and you will realize that it does not matter what weather we had a thousand years ago - or 6,000 years ago where we had an increased and significant warm spell. The Arctic sea ice is disappearing, rather rapidly..

Climate Changes

"I'm not fooled, I doubt any of our regular readers are"

Too right! :D

Climate Changes

"Without scepticism and alternative opinion there is no debate and no science."

When it comes to the scientific method, opinions are irrelevant. Data (observable&byproxy data that is) and findings via studies are what you should be looking at.

mark

Thank you John and Neven, I accept I am not perfect but at least you have manners when telling me so - I shouldnt be so sensitive I suppose.

I started off thinking about the now and I wish I hadnt been provoked into looking back - hey ho cant undo it!

Mark

mark

Perhaps you consider the vineyards as an untruth, I used them as a known example, the bulk of my references (I have been very careful not to say ice free even though the following reference mentions it) are here http://blog.lib.umn.edu/stgeorge/geog5426/Lamb%20Palaeogeography%20Palaeoclimatology%20Palaeoecology%201965.pdf and chinese fruit trees as an example of medieval warming here http://ruby.fgcu.edu/courses/twimberley/EnviroPol/EnviroPhilo/WarmPeriod.pdf .

*snip*

[that's my final snip; N.]

Martin Gisser

Regarding the ridicu-lousy medieval English vineyards: Meanwhile they have vineyards in Norway, above 59°N which is north of Scotland (Orkney Islands). A meanwhile outdated sample list:


  • Eventyrvin and Lerkekåsa Vineyard, Telemark county, Norway. 59°40′N 09°19′E

  • L’Esprit d’Edvard Munch, Vestfold county, Norway. 59°25′N 10°25′E

  • Blaxsta Vineyard, Södermanland County, Sweden. 59°03′N 16°35′E

  • Vinhuset Halls Huk, Gotland Island, Baltic Sea, Sweden. 57°56’N 18°44’E

  • Gute Vingård, Gotland Island, Baltic Sea, Sweden. 57°09′N 18°19′E

So, are we meanwhile way above the MWP?

idunno

http://nsidc.org/arcticseaicenews/2014/09/arctic-minimum-reached/

also

http://www.theguardian.com/environment/blog/live/2014/sep/23/un-climate-change-summit-in-new-york-live-coverage

mark

good grief, the reference above acknowledges that there were vineyards in Norway during this period too but that the seed record has them ascending 200m in the warming period - an estimated increase of 1 to 1.5 degrees C. In Greenland the records kept by Viking settlers had little evidence of pack ice in the 10th century and their shipping routes indicate that Baffin Bay was relatively ice free with strong settlements on Ellesmere Island based on hunting, whaling and fishing. The early viking buried their dead in ground then that now is never unfrozen. And the permafrost has roots contained in it from this period which indicates that it was frost free for a large part of the year, suggesting an increase in temeperature over those believed to be the mean in 1965 of 2-4 degrees C, which puts my 1 degree as well within those parameters and also takes in to account the greater amplitude that tends to be found in the Arctic.

The bibliography on my reference predates by quite a way discussion of GW of any kind. Seeing that this sort of record exists and its more in my sphere of interest, I think it can be reasonably suggested that these periods have occurred before, which was my argument at the start. That would lead me to think that this is possibly cyclical because we have not reached a point that is more ice free apparently than the years 900 - 1200 and perhaps more recently to a lesser extent the period 1750 - 1850.

mark

I notice the references didnt continue down a line -
http://blog.lib.umn.edu/stgeorge/geog5426/Lamb
%20Palaeogeography%20Palaeoclimatology%20Palaeoecology%201965.
pdf

and
http://ruby.fgcu.edu/courses/twimberley/EnviroPol/EnviroPhilo

I have edited these from the preview page as cant get them to 'self' return down a line
/WarmPeriod.pdf

Connie Quirk

"...the medieval Oprtimum as I understand it is N Europe as compared to average temperature since 2000 - its open to a certain amount of variation but most commentators I have read would still say it was warmer by @ 1 degree."

Ah! So we are talking about different things. The North Atlantic region may well have been warmer during the so-called MWP. The globe, not so much. That was the surprise of Mann, Bradley & Hughes (1999.) The basic result that present temps exceed MWP on a global scale has been reinforced by subsequent research, as I think you can find in my previous link to AR5.

Neven
That would lead me to think that this is possibly cyclical because we have not reached a point that is more ice free apparently than the years 900 - 1200 and perhaps more recently to a lesser extent the period 1750 - 1850.

You base this conclusion on a couple of sentences from a 1964 paper, and extrapolate this anecdotal evidence with very little details to all of the Arctic?

Do you have any idea how much the Arctic has changed after 1964, with regards to air temperature and sea ice cover? Can you tell us how much warmer those spots with frozen ground etc have become since then? And what about palaeclimatology after 1964? Have you even looked into that? Where did you get the Lamb paper from?

It looks to me that rather than with an enquiring and open mind you set out with predetermined conclusions, ie that it's all cycles and AGW cannot possibly have anything to do with it.

I've done my share of trolling, which is why I can be somewhat lenient, but I think this charade has now lasted long enough.

mark

ok fair enough I'm trolled out,

*snip*

mark

*snip*

[No more trolling. Please, return to your own echo chamber and leave us silly alarmists be; N.]

mark

pity - will do

[Great, thanks, have a nice day, no hard feelings: N.]

Martin Gisser

(Sorry for beating the dead horse... Just to set things straight.) Here is a working link to Lamb's famous 1965 paper: http://www.climateaudit.info/pdf/others/lamb.ppp.1965.pdf It says nothing about Norwegian vineyards. Fig. 6 shows vineyards only in the southern half of England. Thus, by accepted denialists' standards Lamb's paper proves that we are now warmer than the MWP. No Hockey stick needed :-)

Chris Reynolds

"Wow, over 100 comments, might be something interesting about Arctic sea ice in all that", thought I.

Vinyards?

Back to the forum, nothing interesting going on here.

Neven

Sorry about that, Chris.

Have a glass of wine. :-)

Jai Mitchell

MINUMUM!

Well, what a significant year. This has been a doozy, I am not just talking about the arctic but rather the appreciable real world weather pattern changes I have seen here in California and on the world's settings. A kind of El Nino and massive hurricanes in the Pacific. Not so much in the Atlantic (yet) due primarily to high altitude wind shear. Weather in Europe? just fine for now, will it be another sopping wet spring? What does climate change have in store?

I can only say that we are only 1/2 way to the known LOCKED IN warming that the earth will experience, the vast majority of that warming occurring in the Arctic due to changing albedo.

Destruction of arctic permafrost and the burning of boreal peat. The IPCC AR5 projections are severely, SEVERELY understated.

Lets not forget that we are talking about the survival of the species here (not about regional temperature permutations in north Europe in 1050 AD!

Kevin McKinney

A couple of links of interest. One on inferred wildfire frequency in the Arctic:

http://www.pnas.org/content/110/32/13055.abstract

Interesting indeed, although I wonder about the assumption that these regional records are more widely applicable to the Arctic generally.

And a succinct piece on the Dark Snow project:

http://www.cbc.ca/player/News/ID/2529486281/

(Cross posted from RC.)

Leslie Graham

"...we are not yet as warm as it was in medieval times. I am just trying to say that the present amount of warming is not without precedent..."

Hi Neven and all.
Been lurking here for two years and never posted before. However, I would just like to say that one reason this blog is one of my favourites is that tiresome concern trolls are not generaly permitted to disrupt informed discussion. So I am confused as to why you seem to have realaxed this policy with regard to the obvious concern troll above?
Are we now expected to tolerate this level of myth-parroting from now on?
I sincerely hope not.
Thanks for all your efforts and thanks to (almost) everyone who contributes to the BTL comments to make this the most informative source on Arctic Ice on the web.
Please don't feel the need to suffer fools. There are hundreds of denialist blogs where they can go to spout nonsense - just not here please.

Neven

Thanks for the links, Kevin.

And Leslie, sorry about that. I wasn't 100% if mark was genuine or not, and I try to give people the benefit of the doubt. I felt I could do this because there's less traffic to the blog.

I also never have had to deal a lot with fake skeptics coming to crow victory when the Arctic sea ice minimum is the 6th lowest on record. There were a couple, and I wanted to show a minimum of hospitality.

But, of course, I won't let the blog's comment section go to the Philistines, as we say in Dutch.

John Christensen

On Atlantic moisture, NAO and the Arctic.

As you see from DMI's 60N weather image there is currently a massive low covering nearly the entire Norwegian Sea, or about 5,000,000KM^2:

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

Now, if the NAO had currently been strongly negative, this low would move straight North, bringing a tremendous amount of moisture into the center of the Arctic region, which would delay/slow down sea ice accumulation there.

While the low is still at a distance, pressure gradients in the central Arctic are low, so the weather is relatively quiet, dominated by a much weaker low centered in the Laptev Sea (also not surprising given the open water there). The low pressure gradients have allowed surface temperatures on the DMI 60N image (above link) to move below -15C for the first time this season in a small area between the Pole and Beaufort.

The NAO is right now positive, but not strongly:

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao_index.html

However, this should be sufficient in ensuring that the massive low moves North-East skirmishing the Norwegian mountain ranges, dumping loads of snow there/releasing heat, before the low probably enters the Barents Sea near the Russian North coast. The current jet stream then would push the low south due to a blocking high in Siberia, but IMO it might as well cut its own path towards Kara and then Laptev causing still massive precipitation, but with a considerably colder core temperature when reaching central Arctic areas than we would have seen under strongly negative NAO.

It will be interesting to watch how this plays out the next two-three days, as it should be a classic example of how the NAO steers the North-Atlantic lows.


John Christensen

For those who can read Norwegian, an update on this storm:

http://www.yr.no/nyheter/1.11953411

As is stated there, they expect precipitation as rain and not snow, but in Northern parts of the country up to 140mm in two days, which is a lot.

iceman

@ Leslie Graham

I don't think Neven was necessarily mistaken in trying to engage earlier in the thread - despite the outcome. If someone appears genuinely open-minded, and happens upon some of the abundant misleading information or discredited views available, it could be worthwhile to show them the basis of mainstream scientific thinking.

Note that one of the major contributors on ASIF admits to being a former climate sceptic.

John Bilsky

Good and proper science takes time. A good scientist must be completely above "ego". EXPLAINING good and proper science to those with little understanding takes even more time. Deniers are a hard lot to teach. Explaining good and proper science to those who DO have some understanding but who, for whatever reasons, (ego???) cherry pick information to obtain results they prefer to have is practically impossible. It IS however highly entertaining to watch the process unfold.

I wish I was still in the classroom teaching. This entire thread would be mandatory reading as an exemplary example of the scientific method in action.

Thank you Neven for this incredible resource you have created.
Now it's back to lurking and my coffee which, BTW, was not grown in Greenland.

Leslie Graham

"...I try to give people the benefit of the doubt...."

I spotted him in 5 seconds flat - but then, after 15 years of debunking climate concern trolls every day, I've developed a keen eye for them.
Also I'm not such a nice guy as you.
They are a complete waste of time every time in my experience.
Thanks for taking the trouble to reply however.
I'll go back to lurking now. : )

John Christensen

Last comment on the North Atlantic low, which has now become an Arctic low:

What I did not spot a couple of days ago was the high developing over the CAA, which attracts the North Atlantic low, breaking it into two, where the majority of energy now moves straight North from the northern-most point of Norway and across Franz Josef Lands towards the Pole. A minor fraction will follow the jet stream moving south-east towards the Ural mountain range:

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

You can see this play out on the CT forecast:

http://globalweatherlogistics.com/seaiceforecasting/gfs.850mb.height.vort.arctic.html

John Christensen

Sorry, let me retract my last comment:

The jet stream apparently moved a bit south over the weekend, so that by Sunday it was crossing Norway rather than going around the Scandinavian peninsula on the north and then going south:

http://www.wunderground.com/global/Region/EU/2xJetStream.html

Due to the new position and probably the strong blocking high over Siberia, the jet stream had a less pronounced northern direction just east of the Scandinavian peninsula.
The low therefore seemed to follow the road of least resistance moving straight North.

This event has now played out with the center of the low placed between Franz Josef Lands and the Pole by Monday morning, European time:

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

Regarding the question of the impact of NAO on Arctic sea ice, let me summarize from this event:

- NAO index was medium strong and positive (1.5), increasing westerlies across Northern Atlantic
- This caused the cyclone to move to Norway from its prior position just north of Iceland, which is an ENE direction
- The cyclone then entered the Barents Sea, now in a NE direction
- Finally, it got redirected going straight North, where it seems it will dump its final load of moisture across the central area of the ice pack
- The positive NAO therefore did not prevent the low from entering the Arctic - but it significantly extended the distance for the low to reach the Arctic from Iceland, in which time the system is reduced from a heat/energy perspective


Jai Mitchell

Re: wadham's .8 meters

couldn't find much but I did find this:

Tweets from the Royal Society Meeting on Arctic Sea Ice Reduction: the evidence, models and global impacts

found under #RSArctic14

Informal survey of when #RSArctic14 delegates think Arctic will be ice free: most think 10-30 years from now

— Steve Smith (@stv_smth) September 23, 2014

Zhang: 2025 arctic sea ice volume will be 1/6th of the 1979-2012 average

Marika Holland shows variability can add 20 years to uncertainty in Arctic ice-free timing. Decades with no trend not uncommon. #RSArctic14

— Ed Hawkins (@ed_hawkins) September 22, 2014

Maslowski: Ocean Eddies bring Pacific water into the Chukchi Sea under the ice cover. Max Temp is 40m below surface #RSArctic14

— Mark Brandon (@icey_mark) September 24, 2014

.@BBCAmos on research discussed at #RSArctic14 meeting: ‘Melt ponds successfully forecast Arctic sea-ice extent’ http://t.co/IBRciIWnFY

— The Royal Society (@royalsociety) September 24, 2014

Nicolaus: showing that transmittance of light much greater through melt ponds. they are "Windows to the ocean" #RSArctic14

— Mark Brandon (@icey_mark) September 24, 2014


Schmidt: methane could be seen in ice cores but smeared out. Should expect to see pulse of up to 400 ppb methane #RSArctic14

— Mark Brandon (@icey_mark) September 23, 2014

Rebuttal: What if the 50GT of methane was released slowly during the last 500 years prior to the late Eemian maximum? Would the ice core smoothing effect show more than a trace anomaly increase? Since there is no paleoclimate scenario within the ice-core record that approximates the RCP 8.5 scenario, the assertion that this provides any assurances is false and should be considered "magical thinking".

[fixed html; N.]

John Christensen

One more update on the Arctic low:

DMI has a great graphic showing that as of yesterday the cyclone seems to have put the ice into significant motion with a current speed similar to what you see in ice-free waters (Select surface current and Arctic Sea):

http://ocean.dmi.dk/anim/index.uk.php

This seems to be possible, as the strongest winds of the cyclone follows the same area, where we saw what appeared to be an undercurrent of warm waters leaving the Laptev Sea in a counterclockwise movement towards the Pole and then south into Barents Sea between Svalbard and Franz Josef Lands from late July into September. No doubt that this movement of ice and mixing with top water layers will delay freeze in the area, helped by the temperature increase caused by the cyclone, as is clearly visible on the DMI 60N weather graphic.

The next strong Atlantic fall cyclone is shaping up between Greenland and Iceland, and with NAO moving towards neutral state the cyclone may take a more direct path to the central Arctic Basin.

Ghoti Of Lod

I'm struggling with the notion that the NAO or AO is a causal agent. To me they are more a means of describing large scale weather patterns than the cause of that weather. I suppose it is a chicken and egg sort of situation.

We've read how the extremely persistent ridge was a prediction of models testing reduced Arctic ice conditions.

We know how the ENSO ocean temperatures affect pressure patterns and the resulting weather.

I also thought that a reason for the 3 month running mean being used for describing the state of the NAO was also an indication it is used as a more general description of large scale weather conditions rather than a short term driver of them.

In any case it is interesting to read about the NAO being used to "predict" short term weather patterns.

John Christensen

Hi Ghoti Of Lod,

Thank you for the interest!

The 3 month running mean of the NAO has been used primarily to perform causal analysis of NAO impact during winter months, while there has been little focus on NAO during summer months.

You see the impact of the current cyclone very clearly on the DMI graphs, such as in the latest image, where temperatures have increased significantly in the cyclone impacted area near the Pole:

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

If strong westerlies (positive NAO) caused this North Atlantic low to travel further, before it reached the central Arctic Basin, then the low could have lost 15-20% of its energy, compared to a negative NAO situation, where the low could would have followed a more direct route to the Arctic Basin.

I will check if DMI has done more analysis on this.

John Christensen

Again on AO vs. NAO:

One might ask; if the current cyclone is harmful to the ice, how could the high frequency of cyclones during the summer of 2013 be preserving the ice cover?

Two reasons for this:

1) There are lows and then there are very destructive lows: Last summer we had the combination of positive AO (indicating prevalent Arctic low pressure), but also positive NAO, which means that stronger North Atlantic lows were steered east/north-east rather than moving straight north in the Atlantic. Consequently, the Arctic cyclones last summer did not contain a high amount of energy and further, as Neven included in the great entry on cyclones last year, the difference in temperature between warmed continents and cold Arctic Ocean in itself helped to sustain the cyclones, so that these were to a certain degree separated from strong inflow of ocean heat - at least from the Atlantic.

2) The timing: A cyclone in June or July will increase cloud cover, limitation sun radiation, which in that period happens 24 hours a day. Now by late September, the Arctic is cooling, so a cyclone would necessarily be driven by oceanic heat/moisture, which increases the temperature in the areas of the Arctic impacted by the central low pressure area.

jdallen_wa

John Christensen - thank you for the succinct summary. It laid out what I was thinking far more clearly and completely than I would have.

mark

Surely timing and strength is everything, at an ice forming time especially a little later than this cyclones will open up more areas of water - that leads to greater freezing and thickening of the ice. During summer and around now cyclones are much more destructive as they break the ice up and contribute to thawing.

I would have thought that the strength of the subpolar and subtropical gyres would have a great effect on the effect of the NAO and to a smaller extent vice versa.

What is the delay of ENSO activity to weather patterns in the N Atlantic - is it immediate or does it have to travel with the Global Overturning Circulation before it has a direct effect. Or if not El Nino, would the recent extensive ice cover in Antartica have a weakening effect on the N Atlantic Gyre and make strong NAO differences mor effective.

jdallen_wa

Surely timing and strength is everything, at an ice forming time especially a little later than this cyclones will open up more areas of water - that leads to greater freezing and thickening of the ice. During summer and around now cyclones are much more destructive as they break the ice up and contribute to thawing.

Wishful thinking. Those self-same cyclones are drawing more heat into the arctic which is slowing the refreeze. In addition, the rate at which heat can leave the system via re-radiation is a fixed function of temperature. More heat into the arctic to offset the loss means that much less which can be shed later to thicken the ice.

The cyclones simply are not good for the refreeze energy budget.


I would have thought that the strength of the subpolar and subtropical gyres would have a great effect on the effect of the NAO and to a smaller extent vice versa.

This I'm not so certain of and will leave others to respond to.

What is the delay of ENSO activity to weather patterns in the N Atlantic - is it immediate or does it have to travel with the Global Overturning Circulation before it has a direct effect. Or if not El Nino, would the recent extensive ice cover in Antartica have a weakening effect on the N Atlantic Gyre and make strong NAO differences mor effective.

What effect the delay the ENSO will have, again, I'm not certain.

You would have to work very, very hard to find any direct effect of Antarctic icecover on the N Atlantic Gyre. In short, your supposition is pretty difficult to find any support for. I know of none. The Antarctic is far more isolated by circumpolar circulation than the Arctic is, and is further isolated by the tropics. There's precious little which crosses those barriers with any sort of haste.

mark

Iwas reading a very long extract of 'Ocean Circulation , mechanisms and impacts' by Scmittner, Chiang and Hemming (2007)(I'm having trouble getting the references to behave when I try to include them)!)when you posted. This assimmilates various studies and concludes that the volume of the currents involved in the GOC is greater than first thought. As one of these streams draws heat directly from the Indian Ocean and from the Antarctic Circumpolar Current, it wouldnt be unreasonable to expect extra cooling in the Southern Oceans to have a delayed action on the N Atlantic meteorology and oceanography and as El Nino starts in the E Pacific and transfers west it could also be reasonable to think that that would ultimately impact on the Atlantic as this heat transfers through the Indian Ocean via Indonesia.

mark

Sorry should read 'Schmittner'

philiponfire

mark the thing you need to know about the Antarctic is that it is melting rapidly and that is a bad thing. As a trivial side effect massive land ice loss is contributing to a significant but trivial increase in sea ice area.

mark

Philip - I am just trying to make sense of the 'heat conveyor' structure. I wouldnt dare come on here and pass a personal view again. @ 50 years ago the equatorial part of the meridonal overturning flow, if this report is correct, was estimated at @ 6-8sv but now is generally accepted as 2 -3 times that and if Wikipaedia is to be believed (in this case its very doubtful) several times greater still. That being the case it would mean that there is an increased potential to affect the temperatures and flow of the many aspects of atlantic and polar gyres. As the main component of the S Atlantic MOC comes from the western Pacific through the Indian Ocean and around S Africa it wouldnt be too far fetched to think that El Nino years in the Pacific would have a measurable effect on Atlantic flow a year or so later when the current has progressed that far. The report I read suggested that this was the case but didnt appear to be supported (I dont have the entire book). I wonder if there are any other studies on this possibility as I am currently looking.

jdallen_wa

"...a measure able effect on Atlantic flow a year or two later..."

I think here you have the crux of what I was chafing at earlier - time frame.

Blindingly fast changes on a geological scale still take years, and that is the timeframe required for the effects of the current El Niño to be felt elsewhere globally. QED the effect of El Niño won't reach either polar region until next year, and forcings felt from that in the Antarctic likely would not be felt in the North Atlantic until 2 or more years beyond *that*.

I think the key is the increase in heat. More available energy will make the entire system more volatile. This is especially so as they change the relationship of various heat sinks with three key physical limits, one fixed, two variable - the freezing point of water, the moisture carrying capacity of the atmosphere, and changes in volume both of ocean and atmosphere brought about by increases in temperature.

The more energy becomes available, the greater the gradients we will see between components of the system. The greater those differences, the more energetic will be the mechanisms the system will use to balance them.

mark

This current flow of cyclones has become more meridional than zonal and these cyclones are coming straight up from the Western Subtropical Atlantic and then moving up over Greenland rather than over the UK and have done so for quite an extended period now. Here in S England the weather has been mostly Anticyclonic for well over a month which is unusual so the NAO appears to me to be more E - W rather than N - S. Is this a feature of weak subpolar gyres or strong ones, as again the scripts I have been reading suggest that we have been in a generally weak period for N Atlantic circulation that may now be strengthening again.

John Christensen

Hi mark,

I think the point is that the atmospheric circulation is complex..

In my comments above, I have tried to simplify matters by focusing on the NAO, but as also explained, the NAO is just one typical blocking high in the NH out of few key ones: North-East Pacific/Rocky Mountains, Greenland, and the Central Siberian Plateau. Right now, the jet stream across the eastern North America is further to the North than usual, and moves south around Greenland:

http://www.wunderground.com/global/Region/CN/2xJetStream.html?

It then bulges towards the North and near Svalbard, after which it bulges to go south of the Siberian high:

http://www.wunderground.com/global/Region/EU/2xJetStream.html

Consequently, you have very cold air from this jet stream meeting warm waters south of Greenland:

http://ocean.dmi.dk/satellite/index.uk.php

Which in turn causes these strong lows to build up on the north side of the jet stream, where they are out of reach so to speak for the jet stream, and are free to move north, as you see happening right now:

http://ocean.dmi.dk/arctic/weather/arcticweather.uk.php

To interpret this situation, it seems that the high across the US Midwest is causing the jet stream to stay further north and therefore to create the jet stream bulge, which allows these strong lows to develop and move north in the Norwegian Sea rather than the typical setup, where the jet stream leaves Newfoundland and crosses the Atlantic more directly towards the British Islands and Northern Europe (which then carries the lows in a more East-bound direction).

mark

Thanks John - thats very helpful

John Christensen

And then the Atlantic forecast for the next few days:

http://globalweatherlogistics.com/seaiceforecasting/gfs.850mb.height.vort.arctic.html

As you see, the high across central Europe will move up across Scandinavia and then merge into a high across the Arctic.

You can see this also on the AO turning strongly negative (Same as high pressure across the Arctic):

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.shtml

If the NAO had been negative right now, there should have been a ridge in the mid-Atlantic to assist pushing the low east of Greenland to the north, but it seems the lack of negative NAO will cause other factors to prevent this low from having any major impact on Arctic sea ice.

And an interesting article on the melt of 2012 and NAO:

http://thinkprogress.org/climate/2013/06/17/2169321/exceptional-2012-greenland-ice-melt-caused-by-jet-stream-changes-that-may-be-driven-by-global-warming/

From this article:

"Professor Edward Hanna from the University of Sheffield’s Department of Geography explains:


“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."

Blaine

Ghoti: The low frequency (3 month average is low frequency) NAO is mostly forced by North Atlantic SSTs. The low frequency AO is still mostly atmospheric noise, with a smaller global warming signal. Consequently the NAO and AO have different primary causality directions, although for both causality partially runs the other way as well. That is the NAO is partially forced by atmospheric noise, and the AO is partially forced by Arctic and North Atlantic SSTs. Even where we are talking about a "noise" signal, they still give a useful summary of the average state of the atmospheric noise for the season.

Mark: My general impression was that North Atlantic correlation with ENSO was only moderate, and was strongest with a NEGATIVE lag of roughly 6 months, that is that the largest effect occurs BEFORE the ENSO occurs, with both being forced by Northeast Pacific ENSO precursor patterns. There also appears to be a significant correlation after ENSO is gone, but coincident correlation is near zero. I've been meaning to check this numerically, which should provide a more convincing answer.

Jdallen: Those storms are dropping enormous amounts of snow into the water. The immediate net heat transfer effect has to be strongly negative. I'm less clear on the ultimate end-of-winter effect, because snow on ice can insulate it and greatly slow ice growth. The storm also took a lot of the relatively small remaining amount extremely thick multi-year ice north of Greenland (yes, that's about the only place there still is extremely thick multi-year ice) and shoved it into the Fram, where it will melt.

John: I think you have that pretty much correct. Very warm water north and west of Iceland has been dominating the North Atlantic weather patterns recently. There've been quite a lot of low pressure systems around there, which is normal for over very warm water.

John Christensen

See contrast in NAO index between 2012 and 2013

Month 2012 2013:
J: 1.17 0.35
F: 0.42 -0.45
M: 1.27 -1.61
A: 0.47 0.69
M: -0.91 0.57
J: -2.53 0.52
J: -1.32 0.67
A: -0.98 0.97
S: -0.59 0.24
O: -2.06 -1.28
N: -0.58 0.90
D: 0.17 0.95

John Christensen

To put the anomaly of -2.53 into perspective, of 192 summer months (JJA) since 1950, we have had just six with a negative NAO anomaly above 2:

July 1993: -3.18
June 1998: -2.72
June 2012: -2.53
July 1962: -2.47
Aug. 1980: -2.24
July 2009: -2.15

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table

However, if you combine the NAO values for JJA, 2012 has the highest negative number..

John Christensen

Another trivia on negative NAO (NAO-): The longest period of NAO- since 1950 was Oct. 2009 - January 2011.

I saw somewhere (failed to mark the page) that there was a negative correlation between NAO- and NH average temperature, which intuitively makes sense, since NAO- enhances the polar heat sink effect by increasing the transport of Atlantic moisture to the polar region.
Interesting question: Could the predominance of NAO- since 2008 have assisted in the much discussed 'break' in global temperature increase?
Just with the side-effect that Arctic sea ice is melting away under NAO- in the last few years, because it cannot withstand the increase in Atlantic moisture inflow as well as it could back in the 60's and 70's..

jdallen_wa

Blaine - lots of snow is falling on water yes, but in fact, the actual effect of that snow on heat transfer via phase change is small.

Consider, even 40 CM of wet snow will not be more than the equivalent of 4 or so CM of rain, so the heat transfer would be similar to that required to melt 4CM of ice. In net, if we compare radiative loss under clear skies, I suspect snow melt over similar periods would cause a lower net loss.

Consider also, the effect of imported heat (via moisture), higher humidity and cloud cover. All of those point to higher heat retention and decreased ice formation. The radiative loss through cloud cover and "damp" air should be much lower. The tendency systemically will be to lock temperatures at around freezing, which won't be good for making ice.

John Christensen

Exactly jdallen.

wayne

Yes I notice a recent warming throughout the entire Arctic like "presto"
it gets warmer. Seen here on this ASIG:

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

The entire North atmosphere warmed when North Atlantic air got transported upwards over Greenland it seemed. This gave interesting effects, namely the sunset of this evening shifted Southwards of yesterdays position. The warming is not only surface based but on the entire upper air profile. A sudden shift in warming like his causes havoc everywhere else southwards, especially from the wandering jet stream. Look back on the same graph and notice more enormous variations above the average trend this past spring.

wayne

Shifted Southwards not by very much. .........

Blaine

Don't forget that the heat of vaporization is around 7 times this, or to use your example around 28 cm of ice, which is not that inconsequential this early in the season, with the sun still significant in much of the Arctic. There is some moisture brought in from elsewhere, but the evaporation is still mostly fairly local. There is strong cooling from evaporation of snow at lower altitudes near the surface, from sublimation of snow which never even reaches the surface. The direct deposition of snow comes on top of cooler air temperatures.

Overall, storms like this powerfully transfer heat up away from the surface into mid levels of the atmosphere. If you're talking about total top of atmosphere radiative effect, yes, there's a net warming, but it doesn't occur during the low pressure system itself but around it. Watch the Greenland Sea SSTs rapidly drop over the past couple weeks.

The heat transfer effect will diminish more rapidly than the radiative effect as the surface cools and water vapor pressures fall.

Storms also cause advective warming to the east and north, and advective cooling to the west and south (in this case northwestern Canada).

We've had stormy conditions over the Beaufort Sea, Baffin Bay, extreme northerly Greenland Sea, north and west of Iceland, and also at the typical NAO- southerly low pressure area near Europe. The last is rather odd since it's been generally a NAO+ pressure map.

The corresponding warm areas of the current weather systems have been north of the Russian coast and near the pole (as has been linked in the DMI 80N graph). I don't tend to worry much about the pole not freezing solid, but I suppose worries about not enough ice on the Russian side due to this type of weather pattern are valid.

mark

Thanks John for the NAO index chart - I had a good look at that right back to 1950 and although there could possibly be some correlation to the 1998 El Nino and the 2012 extreme melt season there doesnt seem to be any direct link to extreme weather/ice events other than the effect of a high index. I of course may be wrong but the high index often results in a more extreme event but other times when extreme events like El Ninos in the 70s or the 2007 melt season as an example didnt seem to produce a noticeably positive or negative monthly index in fact often the NAO seems to be broadly neutral. Can it then be concluded that high NAOs are probably a result of chaos theory and therefore unpredictable in timing and strength.....the high indexes being a combination of weather events that result in extreme conditions.

jdallen_wa

A simple model for meditation on said topic (weather and chaos)

https://math.uwaterloo.ca/applied-mathematics/sites/ca.applied-mathematics/files/uploads/images/dpend.gif

Consider our "complex pendulum" has many more articulations, and that the lengths of legs and weights at junctures are changing over time.

John Christensen

Hi mark,

There is a lot of speculation around what impacts the NAO. From what I have seen, it seems most likely that events in the tropics are shifting the ridges across the Atlantic, thereby impacting the NAO.

I am not arguing that the NAO would be the sole contributor for any event, and for extreme events such as e.g. the melts of 2007 and 2012, you need multiple factors to coincide, creating the perfect storm.

However, when you look at monthly NAO values combined for June, July, August and rank the years, you get very prominent rankings for post-2007 years, even to some degree for 2014, while 2013 is near the bottom of the list:

Year JJA
2012 -4.83
1958 -4.67
2011 -4.14
2008 -3.82
1993 -3.65
2009 -3.55
1998 -3.22
1980 -3.03
1954 -2.75
2014 -2.47
2010 -2.46
1957 -2.46
1962 -2.17
1987 -2.13
2007 -2.03
1956 -2.02
1963 -1.84
1974 -1.54
1950 -1.37
2000 -1.35
1977 -1.30
1960 -1.26
1968 -1.13
1952 -0.77
2001 -0.52
1951 -0.49
1966 -0.39
1969 -0.33
1997 -0.30
2004 -0.24
1982 -0.22
2005 -0.19
1991 -0.08
1985 -0.06
1981 -0.01
2003 -0.01
2006 0.01
1971 0.22
1986 0.25
1975 0.45
1988 0.57
1995 0.60
1999 0.61
1984 0.66
1989 0.71
1953 0.78
1978 0.88
1973 0.90
1965 1.06
1959 1.20
1992 1.21
1961 1.37
2002 1.38
1964 1.42
1990 1.48
1955 1.73
1970 1.75
2013 2.16
1996 2.25
1972 2.38
1976 2.40
1994 3.21
1967 3.25
1979 3.39
1983 3.79

Total NAO for JJA is: -20.73 with an average value of: -0.3189

Regarding the 2007 event:

- From the monthly NAO values you see that Aug-Sep-Oct of 2006 had a combined NAO index of -5.59, the most extreme negative NAO index for any three consecutive months in the entire NAO record:

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table

- On CT Area data you notice that late fall/early winter of 2006 set a new negative area anomaly record of -1.5M KM^2, and that the CT area for the first week of February 2007 is still the lowest on the record:

http://arctic.atmos.uiuc.edu/cryosphere/arctic.sea.ice.interactive.html

So IMO 2007 happened because of extensive ice export via Fram during the summer of 2007 and unfavorable high pressure areas, but also because of the very low ice cover/late freeze during the winter of 2006/2007, where negative NAO was a factor in delaying/reducing the freeze.

mark

your reading of that data is a work of art John! (or should I say a work of science). I had a look with a view to highs and lows and runs of positive and negative NAO and couldnt see a pattern. It would be so convenient to be able to link it with flows and temperatures in the ocean as then you could start to find causal factors - far to complex I reckon. It is interesting though that warming and more negative NAO states seem to be a feature of a weakening subpolar circulation. Maybe a reason for the rebound - a balancing action, but more short term. For the long term changes I would think the deep slower denser currents would come in to play

mark

Its very interesting to see how many of the recent years are at the negative end (theres always at least 1 that bucks the trend) when looking at the JJA main melting season totals. It sort of supports the general consensus on the weakening circulation IMO.

John Christensen

NAO and high pressure across Scandinavia:

Fascinating: It seems from the forecast

http://globalweatherlogistics.com/seaiceforecasting/gfs.850mb.height.vort.arctic.html

that the high across Scandinavia does not make it to the Arctic in time to cut off the low north of Iceland, which means this low will enter the Arctic and become another cyclone.

This is what the NAO forecast is showing as the NAO turns sharply negative for a short period:

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/new.nao_index_ensm.html


Also when you see the bulging jet stream, you see how we continue to be bordering a negative NAO situation, with a north-bound jet stream in the Norwegian Sea:

http://www.wunderground.com/global/Region/EU/2xJetStream.html

This bulging jet stream has been with us for a few months, and while we have just entered October, and the Siberian cold is not strong yet, the question will be if the high across the Central Siberian Plateau will arrive early and strongly enough to push west in which case the jet stream is likely to keep bulging and we could easily have a winter with primarily NAO- and reduced sea ice buildup.

I have no idea, if the bulging of the jet stream caused by the Siberian blocking high is a "true" NAO-, or if the blocking high just creates a situation, which resembles NAO-. However, the consequences would probably be the same: North-bound jet stream in the Norwegian Sea, enhanced snow cover in the Arctic region, but reduced ice volume increase.

NH Snow cover and NAO:

If NAO- really transports extra moisture into the Arctic region, then there should be a positive correlation between NAO- and NH snow cover.

While I did not perform any quantitative analysis, it is interesting that for the month of December, the three years with highest NH snow cover are:

1. 2012
2. 2010
3. 2009

http://www.ncdc.noaa.gov/snow-and-ice/extent/snow-cover/nhland/12

If I had done more analysis, I would have had challenges: In the 60's - 80's, it seems like strong negative NAO during fall months, did not result in extra snow cover. What does that mean? My uneducated guess is that the increase in ocean heat energy in the past 30 years has caused NAO- to transport much more moisture and energy into the Arctic than happened with a similar NAO- fourty years ago.

Therefore, AGW may be enhancing the impact of a natural phenomena such as the NAO..

mark

That globalweatherlogistics graphic is the best Ive seen. That is interesting with the lows breaking into the N Pole over the next few days but reading what is going on with the jetstream is beyond me with stationary lows over the Irish Sea and Canada and large lows in the Pacific running into a brick wall over Alaska. Weird but volatile I think youre a brave man to take on a prediction!

P-maker

Yolo - ” If the tar sands are fully exploited it's game over.
Terry”

c.f. http://forum.arctic-sea-ice.net/index.php/topic,861.msg37848.html#msg37848


Dear Terry

No it’s not!

The tar sands may eventually become our rescue. Think of a scenario, where the Arctic tundra starts to disintegrate in earnest -full scale - across the Northern Hemisphere. Under those circumstances, it would be wonderful to have a close-by reserve of asphalt at hand. Think about a situation, where greenhouse gases (CO2 in a dry disintegration process and CH4 in a wet disintegrating scenario) are threatening our common survival. Having the World’s largest reserve of asphalt readily at hand would soon become a nice and easy way to cover the surface of the melting tundra before complete destruction takes place. To help refreeze the tundra big scale, we would most likely need a cheap white surface dressing to recover albedo losses (due to vanishing snow cover), In this case, we have a small producer of white stripes in Denmark, who may come in handy at one time (see http://www.luxol.dk/index.php?lang=en).

It would be outright stupid, if the Canadians chose to convert their tar sands into liquids and pipe them to the Atlantic coast. The market for fossil oil products would most likely be gone by the time they reach the coast, and they would have lost their biggest opportunity to contribute meaningfully to a “soft landing”. Actually, I think the Canadians have a moral obligation to conserve the tar sands for later use to the benefit of the World’s more vulnerable populations.

So, with XL keystone decision just around the corner, and with the minimum of intelligence displayed by our Canadian friends, I think I’m still barely within the limits of this thread…

P-maker

We have now passed the minimum and some important players have passed a sharp corner.

Today, it was announced that the World's largest toy producer has decided to end commercial activities with Shell -mainly after a public (6 million people signed up!) manifestation.

Read the full story here: http://www.thelocal.dk/20141009/lego-drops-shell-after-greenpeace-campaign

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Your Information

(Name is required. Email address will not be displayed with the comment.)