Technical Note: Sorry for any recent performance issues. We are working on it.
This is a thread to discuss issues related to the 2011 Arctic sea ice minimum. The following graphs will update every day:
JAXA Sea ice extent:
Cryosphere Today sea ice concentration:
Burgy says: “where are the fulfilled predictions/forecasts that the models have predicted?”
here’s a (partial) list – if you’re sceptical friends are looking for weather forecasts, climate models are not what you want, just pay attention to the news.
Do you have a reference for the “predictions of more and more violent Atlantic hurricanes”? And is that “(more and more) violent”, or “more, and (more violent)”?
Didactylos @ 250, as I recall, that offhand remark of Planck’s did not stand up to an actual study.
If it is the holy duty of every diagram connected with climatology to “prove global warming” and of every such in biology to “prove evolution”, things may start to get boring soon. Even absent, some sort of people seems too dictate the discussion to an extent they should not be entitled to
REPOST: Previous was not properly formatted and difficult to follow. Please post this, instead.
@249 john burgeson says:
28 Jul 2011 at 8:33 AM
understand the chart ok. as I can. Of course, by itself, it does not support the IPCC thesis — at best it is congruent with it. It says only that the ice in the Arctic is slowly changing.
No, it says the ice is changing suddenly, massively and, if you dismiss climate change, without reason. That’s an absurd hypothesis, isn’t it, that the ice would be disappearing without reason? And this is where your argument reaches into absurdity, along with every other denialist out there. It is not enough to say you don’t accept the most logical and reasonable interpretation of a huge array of data, you must provide a reason beyond “i just don’t think so” and, more so, must offer an alternative explanation.
What is your alternative explanation? Too many yellow twinkies absorbing sunlight? Too many farts? We know it isn’t the sun, itself, or volcanism, or the position or inclination of the planet, so what is it? Occam’s Razor applies: if you know adding GHGs to the atmosphere will raise the temperature of the atmosphere, and by roughly how much, and that happens, *and* there is no other explanation, “I just don’t think so” doesn’t cut it.
When presented to an adult, who last saw a science class (if he did) years ago, it is simply not a relevant argument at all.
Do not confuse the quality and vastness of the science with the ignorance of the populace. If that chart does not scare the bejeezus out of you, it is ignorance at play, not a lack of relevancy in the science. What that chart says, if you don’t accept the science, is that the Arctic is rapidly, massively changing without reason. That’s even scarier than attributing it to climate change. The implications are the planet is so vastly variable the chances of maintaining civilization are pretty much slim and none. Or do you not understand the chart to represent very large changes, not small ones?
Mostly, he sees scientists as “those pointy head impractical kooks.”
This is a very recent characterization and is the direct result of propaganda. We are now blaming the science and scientists for the propaganda against them? It is the information that is supposed to cut through perceptions. There’s the data. If the data and implications of it do not cut through the biases, what can? We are left with logic via, as you say, the Precautionary Principle. But the typical American is no more aware of nor impressed by the precautionary principle than they are climate science. No, we must speak the facts and their implications, and do so unambiguously. If there is a problem with the science it is in the disconnect between scientific communication of probability and risk and the colloquial understanding of them. There is nothing in the data or its interpretation that let’s anyone off the hook for their supposed skepticism. No, there is nothing to support skepticism, so it is more properly labeled denial. Given the denial is manufactured, all the more so.
You are the end user. You are responsible for your ignorance, not the science. If you can look at a ratio of 1000′s:0 in terms of scientific papers on the topic and perceive that as significant reason to doubt, the problem lies with you, not the science. In what other field of study is such an absurd ratio accepted as good reason for doubt?
Now the point is that the graph — at best — only says that over a few years span the Arctic ice cap has varied. Sure the trend is down, but this, in itself, is no particular evidence of anything. Everyone knows that “things change.”
False. Calling decades a few years is disingenuous, at best. You are de-contextualizing the data. Does this chart stand alone as the only evidence of climate change? No. Is it ever appropriate to discuss one graph as being conclusive or inconclusive of climate science? No.
This chart is, for one, many thousands of data points, not a single data point. It is a decades-long trend, though that chart only shows a part of it, it is not fair to pretend the prior years do not exist. Additionally, the chart shows massive changes, not small ones. If you are presenting such a chart to people de-contextualized, again, the fault is with you, not the science.
Also, things are not merely changing, they are changing at rates and amplitudes never seen before – and according to you for no reason, jsut because.
I am simply not a “true believer.”
Who is? Do not attempt to imply this is about belief or religion. That unacceptable.
I support the IPCC because there is, to me, at least a 66% chance they are correct — and the precautionary principle says to not support them is folly.
Where does 66% chance come from? The risk is actually 100%. The planet is warming, it is unambiguous and the only cause we can find is anthropogenic. The risk is 100%. There is zero evidence in support of any other conclusion. (There are negative feedbacks and natural variation, but those are accounted for. They do not explain the massive excursion in GHG concentrations and warming – along with myriad other lines of evidence.) The risk is 100%.
But I remain a skeptic.
Yet, there is absolutely nothing to support that. We typically call it a belief or conclusion that has no support or evidence of any kind a delusion. Your argument does not work against climate science, it decreases our trust in your ability to reason. I do not mean this pejoratively, i am simply stating a fact. If you can look at the ratio of data in support of a dominant anthropogenic climate forcing vs the data contradicting that, 100%:0%, and conclude there is a reasonable doubt, what are we left to conclude? How do you defend this?
Of course, the typical way is as you have above: take a very small part of the total evidence and quibble with it. Denial and “skepticism” as it relates to climate always uses this tactic. I have never seen a denial of climate science that addressed the full range of the science. The reason for this is obvious: it was stated succinctly by those sewing doubt that doubt was their objective. They know full well that if they attempt to address the issue on the merits alone their efforts would fail. So they attack scientists’ credibility and cherry pick data then distort it.
Here is another way of approaching the issue. The IPCC reports are based on 4 primary legs:
1. CO2 is a greenhouse gas.
2. CO2 levels are increasing, as we pour more of it into the air by burning fossil fuels.
3. The planet is getting warmer.
4. Complex (they have to be) models forecast the process is not sustainable.
#1 is established.
#2 is an experimental measure over some span of years and seems to be confirmed for at least one location. Probably more than one.
False. Measurements are taken in more than one location and the atmosphere is well-mixed. Spinning this as doubtful is a bit like going to a swimming pool, dipping you toe in the water and saying, “Well, it’s OK here, but we can’t know for sure till we dip our toes in every square foot of surface area. THEN you can jump in, kids!”
The planet seems to be getting warmer. But the measures of this increase are all over the place, mostly over a few decades at best, and apparently (mostly) at the ragged edge of measurability.
No, the planet *is* getting warmer. This is unambiguous. The measures are widespread and robust. Additionally, they match predicted outcomes from long ago and current scenarios. To claim it is at the “ragged edge” is inaccurate and pejorative.
I’m not sure a few mm of sea level rise is really measurable, for instance.
So? Do you have reason for this beyond your own incredulousness?
We are left then, with a heavy reliance on computer models.
You have set up a rather limp straw man argument:
1. There’s not much data.
2. The data is unreliable.
3. I’m not convinced (and it’s your fault, not mine.)
4. The data is unreliable so only models support climate science.
Simply absurd. The data is not only reliable, it is vast. You have absolutely no way to support this claim.
Models which are incomprehensible to a layman — and indeed to most science-educated people who are not involved with them.
Logical fallacy: I don’t understand it, so it can’t be trusted. Yet, we get in airplanes, drive cars, watch TV, use medicines, buy complex equipment… none of which we understand ourselves.
But all computer models (I have built a few of them) are based on a bunch of assumptions.
That’s why they are called “models” and not “future reality projections.” And yet another straw man: There are assumptions about the future in things designed…. to make assumptions about the future, so they are meaningless.
But let us back up to the core of your claim: climate science = models. We already dealt with your dismissal of the data, which is an untenable position. Your argument rests on that false assumption, so crumbles from that. But, additionally, models are not climate science. They are exactly what they are said to be: guesses about the future based on what we know now. They do not generate the data, they are fed the data.
It is both illogical and foolhardy to say we should have a blank, impassable wall at the immediately present moment and not attempt to look forward. Models offer the only way we have of determining what our future choices might be. It is absurd to imply their inherent uncertainty si a flaw and reason to not use them. They are not predictors, they generate possible scenarios. The decisions still lie at the very human level of planning and decision making.
Finally — where are the fulfilled predictions/forecasts that the models have predicted? I am reminded of the predictions of more and more violent Atlantic hurricanes. Has’t happed.
False. Your statement as to violence – power – is simply false and your statement about frequency a Red Herring. Hurricanes do show a trend toward more powerful storms. The issue of frequency was abandoned a few years ago. There was some suggestion in the data frequency might be an issue, but ongoing study has largely dispelled that. Why do you raise a non-issue here?
I know — not yet! But a few examples of successful forcasts made by the models (IN ADVANCE — NOT HIND CASTING) woyld certainly go a long way as talking points. But these have to be macro — ones anyone can see and understand. Perhaps I’ve missed these.
You have not missed them, you are pretending they do not exist.
1. Increased temperatures.
2. Arctic Amplification.
3. Warming greater at night than in the day.
4. Warming greater in winter than in summer.
5. Biota moving in response to temps.
6. Increased humidity globally.
7. Heavier rain events.
8. Increasing frequency and magnitude of floods.
9. Increasing frequency and magnitude of droughts.
10. Arctic Sea Ice melt.
11. Antarctic Ice Cap melt.
12. Glaciers melting.
13. Increased flooding due to glaciers melting.
14. Increasing extinctions due to habitat and temperature changes.
15. Increased precipitation at the center of the Greenland and Antarctic Ice Caps.
16. Ocean acidification.
17. Rhythms of biota out of whack resulting in declines in populations and possible extinctions.
18. Diseases moving to areas before not found.
19. Invasive species disrupting ecosystems.
20. Warming of the lower atmosphere.
21. Cooling of the upper atmosphere.
22. Coral bleaching.
23. Shorter winters, longer summers.
24. Methane/CO2 emissions from permafrost/clathrates.
Shall I go on?
It is a credit to the insight of denial organizations that they have never gone after Arctic ice loss other than to claim it is balanced by Antarctic sea ice gain – ignoring that the two regions are completely different in their geographies, mechanics, and interactions with the rest of the planet. It is easy to claim some polar bears are still alive, so climate change can’t be real. It is not so easy to deny the very obvious photos and other images showing the very real, undeniable reductions in sea ice. Denialists never go there because they cannot spin it or make it seem like voodoo. It is interesting that you do not deny the DATA, but claim the presentation of the data means nothing.
Logical Fail: The is ice melting, but a chart of that is meaningless.
Getting OT here, but since the continental drift story is one of the favorite denialist “Galileo-class” arguments …
Yes, it took a long time for the theory of continental drift to be established…But both theories had a problem. Continental drift lacked a mechanism
The fact that the continents fit together more or less like a jigsaw puzzle was obvious to many for a long time.
The problem with continental drift wasn’t that it presented this observation with no proposed mechanism.
The problem with the “theory” (more of a hypothesis, really) was that a mechanism *was* proposed, but that mechanism was physically impossible. It was properly rejected by most geologists (no one rejected the obviously fact that continents appear to fit like jigsaw puzzle pieces).
Plate tectonics didn’t lead to the hypothesis of continental drift to be adopted. Rather, it offered a mechanism by which the continents could, indeed, move around. It’s more proper to state that it *replaced* continental drift – no one accepts any of the mechanisms previously proposed to explain the jigsaw-puzzle fit of continents.
Once sea floor spreading was observed and the implications understood and plate tectonics put forward as a result, adoption was pretty rapid by scientific standards … of course there are geologists today (emeritus almost to a man/woman) who still reject it, but we have geologists who believe the sun is iron and CO2-forced warming a myth, too :)
The “continental drift” bit is really a relatively unimportant consequence of plate tectonics, which explains a bunch of stuff …
Clouds are key and what I’ve seen so far was much weaker ice surviving the onslaught of summer because of cloudier conditions than say 2007. This does not stop the ice from disintegrating faster than 2007, essentially proving ice volume estimates as being spot on. I still look at the over all picture, carefully along Laptev sea, I think that Fram Strait will have a twin ice dumping channel if ice melts further there.
On dhogaza’s OT point: this is widely accepted, but it’s not even a good thumbnail sketch. For one thing, Arthur Holmes proposed something very like the current mechanism (mantle currents) in the ’30s. I suspect that many geologists were queasy about relying on a hypothetico-deductive approach when they had no way to observe the proposed mechanism at work (great emphasis was placed on efforts to directly measure drift; similarly many geologists resisted the ice-age hypothesis and then accepted it after a field-trip introducing them to direct evidence of glaciers at work).
Oreskes’ The Rejection of Continental Drift gives a very nice account of the debate among U.S. geologists.
“The story of Blondlot is a story of self-deception among scientists. Because many people have the misguided notion that science should be infallible and a fount of absolutely certain truths, they look at the Blondlot episode as a vindication of their excessive skepticism towards science….”
On the subject of the JAXA SEI figures, unless there is an absolutely enormous INCREASE in extent, when the data for the 28th July is posted, 2011 will replace 2007 as having the lowest recorded July average. This will therefore join with the lowest monthly averages recorded in June 2010, November 2010, December 2010 and January 2011 in proving that Arctic Sea Ice is unambiguously recovering. (Or perhaps not!)
If one looks at average annual extent, the 2007 figure (9.966 million sq km) is unsurprisingly lowest by some margin. What may surprise some is that although 2008 is in 2nd place for both the September Minimum and September Average, it has the highest annual average out of the latest 6 years. With an annual average of 10.22 million sq km, 2006 is, at present, second lowest in this respect.
Taking a daily incrementing average from the 1st January each year until today’s date, then 2006 currently has the lowest such figure (11.849 million sq km as of 28th July). By the 24th August, the equivalent 2007 figure converges on and surpasses 2006 – and 2007 then remains lowest until the year end. (NB Until the end of January, 2011 was of course lowest, but the 2006 figures “retook” lowest place from the 1st February onward.)
However, irrespective of the weather over the remainder of the melt season – and indeed till the year end – things will be different this year. Unless I have cocked up the spreadsheet, on the 3rd August (+/- 1 day) the 2011 figure will overtake (perhaps “undertake” is more accurate?) the equivalent 2006 figure.
My crystal ball skills are inadequate to predict how the year-end averages will pan out, but it is difficult to see how 2011 will fail to at least replace 2010 as 3rd lowest annual average, and will probably also replace 2006 in second place.
If the average daily delta over the next 5 weeks is just 37,500 sq km, then the August 2011 average will be the second lowest thus far. (Assuming an evenly distributed drop rate – this projection would obviously fail if the drop profile was back-loaded.)
With an average daily drop rate of 48,700 over the next 5 weeks (irrespective of the profile), 2011 would also have the second lowest end-of-August extent. Intriguingly, with such a delta, this would also see the August month end figure drop below the psychologically important (but otherwise relatively arbitrary) barrier of 5 million sq km for only the second time.
Personally speaking (that has got to be a tautology) I really hope 2011 fails to beat the 2007 minimum. The weather conditions in 2007 were so remarkably conducive to a low minimum – 8 weeks of averaging 91,000 drops, bracketed with two weeks either side averaging 45,000 between them – that we at least seemed to be destined to wait quite a few years before seeing its like again.
If 2011 is already threatening to beat this record, I fear we are running out of time.
@bill the frog.
Nice. Thanks for that.
@State of the Arctic: Northwest Passage OPEN. Appropriate caveats within:
You heard it here first. (Lie if you didn’t.)
Getting hotter and hotter. Yet another feedback…
On the Cryosphere Today image, you can see an island of ice between Canada and Greenland fairly far South. Is that the ice island coming Petermann glacier?
The structure between bering strait and north pole resembles a vortex… can that be, or is this a purely optical illusion?
Juliette @ 262, No that’s not the Petermann Ice Island. It’s just a small amount of residual sea ice sitting in a slow gyre caused by currents in Baffin Bay. It will probably melt out fairly soon.
Petermann Ice Island broke into a couple of large sections which have been slowly shrinking as they shed icebergs. Of the two major parts left, one is currently in the middle of the strait between Devon Island and Baffin Island, and is slowly being pushed towards the Northwest Passage area. This doesn’t appear on the CT maps (if it did it would only be a couple of pixels), but it an be seen on NASA’s MODIS satellite pictures at higher magnifications (eg 250m/pixel).
The other part has been drifting down the coast of Labrador for several months and is currently roughly level with the northernmost point of Newfoundland. Again, this is not shown on the CT map but can be seen on satellite photos. It’s becoming something of a tourist attraction and search engines should link you to recent details of its location.
@ John Burgeson – various
Very few people with a genuine interest in science would have a bad word to say about anyone demonstrating GENUINE scepticism (or skepticism, if you were taught to spell it that way in skool). However, when this word (irrespective of its spelling) is prefixed by the modifiers “climate change”, it invariably becomes an oxymoron of truly singular status.
In the deniosphere, claims are rife about “Arctic sea ice was as low in the ’40s as it is now, and it was just coincidence that satellite telemetry began in 1979 when, by mere coincidence, the Arctic ice was at the maximum in a 60 (or insert number of your choice) year cycle.”
However, there are a few weaknesses with that story. Let’s start with the satellite chestnut. It is of course true that many sites show data from 1979 – that was indeed the start of the multi-channel microwave systems, such as SMMR and progressing to SSM/I, SSMIS and AMSR-E.
However, take a closer look at the University of Bremen site. In particular, have a quick decko at the baseline dates. In the Arctic, this runs from ’72 – ’08 and ’73 – ’08 for the Antarctic. Is this a typing error, or, just possibly, might there be some data to back this up? Could it perhaps have something to do with the fact that there were single channel ESMR devices on the Nimbus satellites? The ESMR dataset is available from NSIDC at … ftp://sidads.colorado.edu/pub/DATASETS/nsidc0192_seaice_trends_climo/esmr-smmr-ssmi-merged/gsfc.nasateam.extent.1972-2002.n
Anyone looking at this dataset will see that, from 1972 – 1978, the average September extent for the Arctic ranged between 7.13 – 7.50 million sq km. As for the 1979 figure – how about 7.07? In other words LOWER than the previous 6 years, and NOT at a transient maxima as claimed in many quarters. (It’s getting to be squeaky bottom time for that 60 year cycle conjecture, isn’t it?)
The September extent figure for the Arctic is currently declining at ~11%/decade, or about 35% since the putative ’79 start date. Therefore, if the extent was as low in the ’40s (or whenever) as now, it must have grown by over 50% from this supposed minima sometime during the interregnum. Now surely somebody would have noticed this by the ’60s or ’70s and produced a scientific paper remarking on the fact?
Unfortunately, and I am sure it must just be my limitations, I have yet to find such a paper. On the other hand, what I have seen is a study available on Cryosphere Today. This is by Chapman and Johnson entitled “Analysis of Arctic sea ice fluctuations 1953-77″, and it was published in the Journal of Physical Oceanography. Chapman & Johnson do record a less than earth shattering increase of, if memory serves, around 80,000 sq km over the 25 year period of the study.
This, as others have observed, does not tie in well with your memory of hearing about some whole scale increase in Arctic sea ice during the ’50s & ’60s.
It’s your call which ever you think might be the more reliable.
A lesson for those who don’t worry about current Arctic ice conditions, where there is no ice, Canadian Archipelago, its very hot, yes hot, often 10 degrees above average.
Where the ice still lies, its much cooler:
A world without Arctic sea ice would be extremely different.
Pituffik, Greenland (Thule Air Base)surpassed record high temp by 11 degrees today. 62F for a high.
What strikes me, looking at the Nunavut temps (ie., the Canadian Eastern Arctic) is not so much the maxima, though there are a few splashy examples of high maxima. It’s the amazingly consistent way in which the daily minima are running about 3 C above norms–there are only a very few exceptions to that pattern. And if I recall correctly, the same was true throughout much of last summer, too.
Most Nunavut stations have normal max/min and a 7-day forecast available here:
#268 Kevin, that is in part because of the lack of sea ice. Now the flow for the main pack over the Arctic Ocean is key, I dont think the low pressure north of Alaska will last the same way as last year.
To Bill the frog:
You must have me confused with some other poster.
To John Burgeson (@270)
“you must have me confused with some other poster”
John, profuse apologies. My only defence is rapidly encroaching senility. I had 3 blog responses buzzing around in my head and managed to mangle them. (2 for RC and one for that stalwart champion of logical thought – the UK’s Sunday Mail)
My comment (265) was meant for Titus, and related to his putative memories of Arctic Sea Ice growth during the ’50s and ’60s.
One of the responses I had in mind was to your comment number 245, and that is why your name was floating around in what is left of my grey matter. The rather delayed point I was trying to make to you was as follows…
You may wish to reconsider the validity of the analogy you are hoping to draw between AGW consensus and the approach of the scientific establishment to the various discoveries that you enumerated.
If you are not already aware of its existence, I would strongly recommend reading Spencer Weart’s excellent “the Discovery of Global Warming” on the AIP website. In particular, have a look at the section called “the Carbon Dioxide Greenhouse Effect”. This, as you work through it, provides a very illuminating timeline and relates how, until the ’70s & ’80s, the scientific consensus was that anthropogenic CO2 emissions were largely insignificant in terms of climate change. (It’s also well worth perusing the bit about Roger Revelle.) In other words, the view of mainstream science has already performed a 180. You don’t often here that being talked about in the deniosphere – it causes too much of a cognitive dissonance.
Most people on this site are well aware of how scientific orthodoxy is portrayed as an inflexible barrier to new ideas; a better perspective perhaps is to view scientific consensus as a sort of garbage collector designed to stop us from getting smothered in trash.
Sorry again about getting my knickers in a twist. btf
Titus (@161, 212 & 229)
A couple of days ago, I tried to respond to your various posts about supposed Arctic Sea Ice growth in the ’50s & ’60s, but managed to wrongly address this to John Burgeson. (See his comment 270 and my subsequent response.)
My comment (265) should have been addressed to your good self, and was intended as a more general supplement to the detailed responses already made by Chris R
Sorry about the rank incompetence btf
Interesting developments over the last few days. Looks like an unprecedented Summer inswinger. Any clues on what might be driving this?
Paul S @273
Depending upon one’s proclivities, this could be ascribed to …
a) natural cycles
b) divine intervention (Sorry, that should, of course, have been Divine intervention)
c) thin, fractured ice being spread out over a larger “area”, or more properly, “extent”, by wind/wave action. (Slight problem with nomenclature there – but I think it’s reasonable to expect that nearly everyone on this site understands the difference between the terms.)
Think of spreading jam over just part of a slice of bread. Now spread it over the rest of the slice. You have increased the area (extent) but you ain’t got more jam.
There was a vaguely analogous slow down last year between about the 5th – 15th July, but not as extreme as being witnessed at the present. It will be interesting to see what the average delta for August has reached by about the middle of the month.
I’m going with spreading jam. I just finished my predictions for sea ice.
It seems the normal Arctic Gyre is returning:
this greatly contrasts with 2010. And favors a great pack ice loss.. Clouds again played a significant role, but in this case the returning beaufort Gyre will accelerate flushing of very weak ice. Again small Russian Islands play a role in adverting an even greater loss. Remains to be seen wheter there is an ice bridge north of Laptev sea, or rotten loose ice.
Am I right in thinking that the eggshell ice we are mostly seeing these days is *less* prone to being moved by winds and currents (especially winds)?
The reasoning is that the ice has few (if any) pressure ridges, and the freeboard is less, leaving the wind with little to push against.
Arctic sea ice extent isn’t everything. In particular it isn’t sea ice volume, which is low.
Is the not so thick ice harder to blow around? It doesn’t stick up so much, or down so much. This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.
Didactylos @278 : That’ll be one of those negative feedbacks I keep hearing about.
This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.
When conditions have been right this year, a lot has been blown out through the Fram Straight, the result being that the Greenland Sea has had higher than recently normal extent at times for the date. It all melts, of course …
“When conditions have been right….” – tautology. ;)
North Pole to Laptev sea ice bridge seems to be collapsing, and there appears new ice flowing out between Severnaya Zemlya and Franz Josef islands. There is a near consistent Low pressure modeled for that area. For this reason 2007 ice extent minima is poised to be severely exceeded.
Let’s have a look on the today’s MIT spotlight:
[Response: The actual story is here. Some statements are a little weird though - all the AR4 models had sea ice dynamics affected by the winds and currents for instance - but one should probably wait until the actual paper comes out to see what is really being claimed. - gavin]
Refutation. You’ve claimed that under such conditions, ice hasn’t been flowing out of the Fram Straight, possibly because being thinner it doesn’t “stick up so much”.
You’re wrong. When conditions have been right, substantial amounts of ice have been flowing out of the Fram Straight, regardless of how high it “sticks up”. The last several days happen to have seen the conditions be … tautological, so to speak … and yes, the ice is on the move.
# 285 dhogaza tells me “You’ve claimed that under such conditions, ice hasn’t been flowing out of the Fram Straight, ….”
actually, I didn’t. We must be misunderstanding each other.
We must be misunderstanding each other.
Seems clear to me, along with your guess that it’s not due to different wind conditions, but rather the ice “not sticking up” high enough to be pushed along by it.
@ 284: http://web.mit.edu/newsoffice/2011/arctic-ice-melt-0810.html
“The Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, released in 2007, forecasts an ice-free Arctic summer by the year 2100, among other predictions. But Pierre Rampal, a postdoc in the Department of Earth, Atmosphere, and Planetary Sciences (EAPS), and colleagues say it may happen several decades earlier.”
That’s automatic. If there is a good chance of an ice free Arctic summer by 2100, then of course it “may” happen in 2100 plus or minus a few decades.
So I think the new study says “probably sooner rather than later.” But this is hardly news. Isn’t that already published?
I mean, even besides by the Navy. As we know, Maslowski of the Naval Postgraduate School has an Arctic regional supercomputer model and finds that the summer sea ice is going down within this decade.
Why isn’t this given more credit? After all, sea ice is vanishing quite a bit faster than the global models forecast, isn’t it?
Anyway, the new thing about the new study (as usual ignore the press release) is I think a new model of Arctic processes. Evidently this new model partly catches up with actual Arctic events.
dhogaza @ 287, “You are misunderstanding me. I am trying to connect to Connecticut but you cut my connection.” Go back to 278 and start over.
Then observe that I replied  “[the thinner ice] It doesn’t stick up so much, or down so much. This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.”
The thinner ice does not stick so much or down so much = the question of whether it is easier to move by wind is not directly settled by the previous observation that it doesn’t stick up so much.
This summer’s winds have not been all in one direction by a long shot. Instead the ice has been blown around rather than in a line, including rather than in a line out the Fram Straight.
Am I right in thinking that the eggshell ice we are mostly seeing these days is *less* prone to being moved by winds and currents (especially winds)?
The reasoning is that the ice has few (if any) pressure ridges, and the freeboard is less, leaving the wind with little to push against.
I’ve no scientific support for this, but my reasoning leads to the opposite conclusion: since, as we know, only about 10% of the ice is above water, and since wind directly operates only above the waterline (obviously), the ice below exerts more drag relative to the force of the wind for larger floes, than for smaller ones. Basically, bigger floes need to move water out of the way.
Forces such as tides and currents are, of course, another story.
FWIW, I’m quite convinced that we’ll see a seasonally ice-free Arctic (by Dr. Maslowski’s definition) long before mid-century. The declining trend in volume, compared with advection of warm Pacific water–presumably relatively constant–(and figuring a modest boost from albedo and water vapor feedbacks) leaves little room for any other conclusion in my (rather simplistic) mind.
Sea ice is becoming more mobile as it gets thinner:
The wind drags on the rough surface of the ice, protrusions from ridging are not a major factor. Thinner ice having less mass and less mechanical strength is more easily moved.
Re the Fram Strait,
Fram Strait export was high during 2007-2008 (exceptionally so), but most of the studies I’ve read find no trend. e.g. Spreen et al 2009. I have recently read a paper that referred to a personal communication from Ron Kwok confirming no recent trend in Fram Strait flux (but I can’t put my hands on the paper, lost in a pile, and can’t recall if that was area/volume flux – sorry – a bit useless I know).
The sea ice is moving more quickly according to one recent study:
The thinner ice is actually more prone to movement due to less mass, less mechanical strength and in summer more cracks.
Fram Strait export shows no trend, e.g. Spreen at al 2009 “Fram Strait Sea Ice Volume Export Estimated Between 2003 and 2008 From Satellite Data.” I have read a paper recently that includes reference to a personal communication from Ron Kwok stating no recent trend – but I can’t recall which paper (I’ve read a lot in the last few weeks).
If anyone can cite papers showing a trend in Fram Strait flux (excluding the exceptional flux of 2007/08), I’d be interested.
This summer’s winds have not been all in one direction by a long shot.
True. Why would they be, and during which summer has it been (depends on how you precisely define “a long shot”, presumably).
Instead the ice has been blown around rather than in a line, including rather than in a line out the Fram Straight.
Instead the ice has been blown around rather than in a line, including rather than in a line out the Fram Straight.
Nope, as I’ve said several times, a considerable quantity of ice has been blown out of the Fram Straight into the Greenland Sea, with the result that for some periods of time this summer the extent anomaly for that area has been high due to all the ice blown into it (which then has melted).
The last few days, as I’ve said several times, has seen quite a bit of movement out of the Fram Straight.
What’s so hard to understand about that?
> volume, which is low
Has anyone shown the correlation over time for these different measures — area, extent, and volume? Seems to me intuitively they ought to end up at zero all about the same time.
Here’s the volume:
Neven’s blog has the color-by-number version:
Neven also has on the same page the exponential-trend with color-by-number. Joe Romm has picked that up; it’s the most dramatic image.
Those needs to be explained — maybe with a pointer to some definitions page I don’t know about. Something like:
JAXA Extent and Area:
“The sea-ice extent is calculated as the areal sum of sea ice covering the ocean where sea-ice concentration (SIC) exceeds 15%…. SIC data could have errors of 10% at most ….
… The area of sea-ice cover is often defined in two ways, i.e., sea-ice “extent” and sea-ice “area.” These multiple definitions of sea-ice cover may sometimes confuse data users. The former is defined as the areal sum of sea ice covering the ocean (sea ice + open ocean), whereas the latter “area” definition counts only sea ice covering a fraction of the ocean (sea ice only). Thus, the sea-ice extent is always larger than the sea-ice area.”
“… For the ice volume simulations shown here, sea ice concentration information from the NSIDC near-real time product are assimilated into the model to improve ice thickness estimates ….”
For your info, I found this on the web page of the lead author of http://web.mit.edu/newsoffice/2011/arctic-ice-melt-0810.html
According to those papers, sea ice not only accelerates, but also deforms and breaks up much more than before
what do you think?
@ Fram Strait I tried tracking this on my blog, but cloudiness and ice breaking up make this really hard for days at a time and you end up just picking new ice to track not sure whether it’s what you were tracking or not, ofttimes.
But this also tells you something. 1. The ice breaks up rather quickly at times. 2. The ice moves quickly enough to make it hard to track as it deforms.
However, I also found floes moving northward closer to the Greenland coast and southward away from it.
Another point is, with all the space north of the islands (Spitzbergen, Franz Joseph, etc.) it is obvious the flow of ice toward the Fram is not significantly large compared to other years when the flow was heavier. part of the issue is also related to the time of the season. Earlier it was easier to track, but as summer wore on, the ice seemed to lose its form much more quickly. I think it is simply melting sooner. However, the flow out of the Fram seemed to move much more consistently and quickly before the pause we had in July. Perhaps it is picking up again, but it doesn’t seem so.
However, there was and is significant disintegration of the ice at the northeast corner of Greenland which is probably at least partly what was flowing out of the Fram before.
As for the direction of flow overall, let’s do keep in mind the obvious: the gyre and the current that skirts Russia are part of the reason the ice piles up north of Canada and Greenland and not Siberia. it is obvious – and you can check the buoy movements to confirm, that the primary flow of ice should be from the Siberian side, and is, unless the winds are enough to overcome the currents (which they often are.)
The buoys along the Canadian and US coasts have been moving with the gyre clockwise, so towards the Bering Strait, essentially, while those that were originally at or near that general location are moving either toward Siberia or down into the main pack.
All this indicates to me the winds are not much overcoming the water movement, although the cyclonic activity has often seemed to be supporting this movement.
That said, the ice spread along the entire western end of the basin indicates winds have either been neutral or supportive of a western/eastern flow. Given the gyre and the primary flow in from the Pacific, the ice would be expected to be hugging the Siberian coast a bit more, but it isn’t, it’s just spreading out. or, just melting where it is. Both, in my opinion. Essentially, there is no really strong bias to the wind and everything seems to largely be moving about as basic dynamics would lead us to expect.
UPDATES at http://aperfectstormcometh.blogspot.com/
dhogaza @ 294, I’m sorry that you misunderstood a comment of mine earlier in this thread. Or didn’t appreciate my #282.
(recall 278 -270 – 280 – 281 282 285 286 289)
You inform me “Nope, as I’ve said several times, a considerable quantity of ice has been blown out of the Fram Straight into the Greenland Sea,….” Yes, I have followed the melt and the changes in ice extent and more this summer. That you misunderstood me earlier is a separate fact. If you somehow read into my comments a claim that an unquantified “considerable” quantity was not blown through, please check and discover no such statement by me.
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