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:
Arctic sea ice discussions
Climate science from climate scientists...
121 Sphaerica (Bob): NRL doesn’t tell me what units they are using. Otherwise, I get the same idea that we had better visit the Arctic while there is still ice to see. What do they mean by 1/12 degrees? The polar web cams make pictures that lack context for me.
110 Bart Levenson: Thanks for that web page of yours.
128 & 130 ccpo and Geoff Beacon vs Jim. Well, sort of. Bart Levenson’s prediction is absolutely terrifying as far as I am concerned, and within science. Why not go with that? We are all quite reasonably frustrated and panicky. What to DO? The Arctic melting ice should be plenty of evidence for anybody. There it is, all that water where ice was before. Any 6 year old should be able to see the difference. The phenomenon of denial is absolutely astounding. Is there a sociology blog as good as RC that covers that sort of thing?
138 Lou Grinzo covers the what to say in the ccpo and Geoff Beacon vs Jim debate. It looks like we all agree. Reality is worse than anything we could imagine or make up. We have to find a way to show the Arctic ice melting to everybody. Arctic ice melting is very easy to see and undeniable. Add some consequences for the rest of the world. It has to be a slick finished production like it came out of Hollywood. The NRL Arctic web cams are not a finished production. It has to be super-easy to understand. It has to be a video with a great sound track. Then put it on Youtube.
Most people have to have a solution to the problem before they will admit that there is a problem. The video has to say that there is a solution. It doesn’t have to say what.
152, Edward Greisch,
In the case of climate change, I firmly believe that the answer is a whole lot of little solutions (behavior changes, like not all commuting at once, or restricting business air travel to what makes sense, more energy efficient buildings, more fuel efficient vehicles, alternative fuel sources, etc., etc.).
I think a whole lot of little changes will add up to what we need, to the extent that people don’t really even notice (or perhaps like) the difference.
Unfortunately, that sort of solution — not a dramatic, sweeping change, but rather a whole lot of little, incremental changes — requires that people first admit to the problem, totally and completely, and address it themselves, on a daily basis, in small, incremental ways rather than sitting back and hoping governments or scientists or engineers will somehow solve the problem for them.
This is what I find most perplexing about deniers, that the very thing that they want to avoid — economic crisis and major lifestyle changes — are almost being forced on us by the unnecessary delay.
Titus: you asked “in a perfect (natural) world what would the ice extent be?”
Well, if your definition of “perfect” doesn’t include humanity, then obviously the planet has seen all extremes from snowball earth to zero ice in the distant past.
But if you think humanity is special, or worth keeping around, then we only know with any certainty of two ice conditions – glacial conditions like the kind you mentioned earlier, for example during the last glacial period, and interglacial conditions, like those we have observed in the modern era (and have been relatively stable for thousands of years). These interglacial conditions are associated with polar ice caps about the size we are used to, before they started to vanish.
We can be fairly confident about this because while sea level has been significantly lower during glacial periods, it has not been noticeably higher than present for the last million years. Sea ice doesn’t contribute to sea level rise, but the entire cryosphere is sensitive to temperature.
Edward, 1/12 degrees is just the grid resolution. http://www7320.nrlssc.navy.mil/hycomARC/prologue.html
ccpo says:
23 Jul 2011 at 6:06 PM
[Response: Oh yeah, that will go over well. And I see you are back to your accusatory ways–Jim]
I have no idea where that is coming from. Who was accused of what? perhaps you feel my suggesting scientists **need** to be more activists is somehow accusatory? If that is your point, I am not attempting to imply any given scientist is not doing what they perceive to be appropriate, but I *am* suggesting this is a time unlike any humanity has faced and that how we handle it will, and must, be different than how we have done things in the past. FYI, it is my opinion this is true of all segments of society, not just scientists.
That people cannot see that any statement deemed less than solid will be quickly jumped on, after all that has happened, is beyond me.–Jim
This line of reasoning is easy to understand and is easy to “see.” Per my above comment, it may not be germane any longer. E.g., Annie Leonard, maker of “The Story of Stuff”, made an excellent observation regarding climate that it was time to simply act regardless of the denialists and essentially ignore them to get onto the business of solving problems.
I think this is a cogent argument. if we simply stop legitimizing denial by not giving it the time of day except to name it and blow past, perhaps that will be more effective than fighting. Of course, this is more true for us lay people. You scientists do need to combat poor science with well-done science to, as you point out, undergird the arguments. But mostly, we need to just blow these people out of the way. Call a lie a lie, bad science bad science, paid hitmen paid hitmen, etc.
And, no, I don’t understand why we should pretend the heat waves, stronger storms, larger floods, etc., we are experiencing are not affected by climate. As numbers of scientists have pointed out, the overall loading of the system should be noted as impacting events, even if we cannot mathematically or experimentally prove it, because we all know it is true. We have no responsibility to pretend otherwise.
Why would the following be imprudent (Not based on any real event)?
“Yes, the record flood and other extreme weather are affected by the rise in temperatures and water vapor since 1900. As a scientist, I hate to say something like that because I cannot draw a line of absolute proof from a given event to the increased temperatures and water vapor. But this is not about the science. Scientists rarely speak of things in terms of absolute certainty. It’s difficult to explain this, but scientific certainty is not the same as risk assessment and policy-making.
When it comes to climate change, we, as scientists, understand the magnitude of the risk, and it is grave. other issues, in fact virtually all policy decisions, are made without any certainty at all. Climate Change is scientifically understood far more than, say, any discussion of economics or budget, yet, we make budgets all the time. Climate has a far higher chance of very large disruptions to society than, say, the chance your house will burn down or you’ll be severely injured in a car crash. Yet, we protect ourselves from those things.
The fact is, there is no doubt, in the sense that you, the public thinks of and talks of things, that climate is changing, is heating up, and is already having large impacts on our society. Is the recent heatwave part of climate change? Of course it is because the entire planet is now in a different condition than it used to be. That is completely beyond debate. Don’t let anyone try to convince you otherwise. Those who claim otherwise have been shown to base their opinions on non-scientific issues. The small areas of concern that are raised in legitimate science are acted on and studied when they arise. They always have been.”
Perhaps you feel this is already being said by enough scientists, but, imo, the way it is spoken by many, perhaps most, scientists publicly is more equivocal than this.
Again, this is not accusation, it is an appeal to continue to increase the amplitude and frequency of this message.
My apologies, again. I really expected you to move my “rant” over to unforced variations and didn’t expect people to be continuing this here. I have to admit I’m glad it’s still here.
Believe me, Jim, I respect the work of all of you and do not mean to sound accusatory. My studies in all other fields and in my chosen avocations/vocations all lead me to believe what I have always said here: time is short. Shorter than most think. I hope to be wrong, but am very afraid I am not.
Here’s to the long solar minimum actually happening.
@#137 jbowers: “This particular dust storm blotted out the sun over the nations capital, drove grit between the teeth of New Yorkers, and scattered dust on the decks of ships 200 miles out to sea. I suspect that when people along the seaboard of the eastern United States began to taste fresh soil from the plains 2,000 miles away, many of them realized for the first time that somewhere something had gone wrong with the land. It seems to take something like a disaster to awaken people who have been accustomed to great national prosperity, such as ours, to the presence of a national menace. Although we were slowly coming to realize that soil erosion was a major national problem, even before that great dust storm, it took that storm to awaken the nation as a whole to some realization of the menace of erosion.”
This is what I fear, and why I do make the ask: Please, more scientists speak more forcefully on this issue.
@145 John McCormick says: So, Jim, you need to look beyond your own work and see the forest, so to speak, and realize we have compelling evidence all around us that climate change is impacting land, people, ecosystems and our future.
John, an excellent example. And there are so many of them.
And Jim B. says:
And I have a very short fuse with those who say things starting “You need to [do this that or the other]“.
Jim, I sometimes rely on context overmuch and am not a specific as I might be, but it should be fairly clear I at no time meant you personally. perhaps you understand that and actually mean you don’t like it when people tell scientists they “need” to do something. Fair enough.
However, the use of “need” is conversational and was not really intended to convey an absolute. Thinking about it, though, I find it does need to be an absolute. I realize you, as a scientist, likely have a clearer perspective on climate than I do. Very, very likely.
The advantage I may have is that my perspective may be more eclectic than yours. For five years I have studied climate and energy… and population… and water… and oceans… and economics… and sustainability… and energy… and water… all in terms of their interactions.
You may have, too. If so, I have a very hard time understanding why your statements are more circumspect than mine are. I think it would be frightening, indeed, to truly understand what our climate is capable of.
But I have found that it is the interactions of all the issues that is the problem for that is the true system, not the climate. Climate is but one piece of the puzzle. It is a highly complex puzzle, but the complexity when we add all the other issues to solving the climate challenge is magnitudes greater.
It is this that I see in my mind. It is this I see when I look at my son. And it is this that compels me to urge the scientists to speak more forcefully. It’s not just climate science, it’s everything. And, yes, i do think we have to draw this conversation around to the full range of interacting issues being part of the discussion much, if not all, of the time. I.e., discussing what to do about climate outside of discussions about energy, water, economics, etc., no longer is a luxury we have.
Jim says: When other people have no income and are living out of their truck for many months on end, while still contributing to blogs and trying to write papers in two different fields, then they can advise me of what I “should be” doing OK?
While I don’t write papers, I have spent my savings putting my money where my mouth is; have had my wife run off, kidnapping my son in the process; am about to lose my home; currently have no income, no public assistance, no unemployment insurance and should have the utilities going off soon. I just cut my own hair, believe it or not. (I’m kinda freaked out it looks OK.)
I am not asking you to do anything I have not already done, and am currently doing.
Glad to know I’m qualified, tho.
;-)
Enough on this. My apologies.
Cheers
ccpo, you needn’t offer any apologies. You are speaking for many, if not all those, who believe what the read, hear and see regarding climate change.
Perhaps Jim is taking this all too personally. But, when he says: That people cannot see that any statement deemed less than solid will be quickly jumped on, after all that has happened, is beyond me.: I find that statement beyond me also. What is really solid are the now, visible and verifiable evidences of climate change impact.
Yes, we smell the smoke, but we don’t have to wait for the chemical analysis of that smoke to know it is time to call 911 and get to safer ground.
I was brought around to speaking more forcefully about current weather/climate events after reading an address by Kevin Trenberth to the American Meteorological Society back in January, in honor of Stephen Schneider.
http://ams.confex.com/ams/91Annual/webprogram/Paper180230.html
The main point resonated with me: “Moving towards a form of operational real time attribution of climate and weather events is essential, but needs to recognize the shortcomings of models and understanding (or the uncertainties, as Steve would say). Given that global warming is unequivocal, the null hypothesis should be that all weather events are affected by global warming rather than the inane statements along the lines of “of course we cannot attribute any particular weather event to global warming”. That kind of comment is answering the wrong question.
Didactylos @ 142,
Thanks for the reply. Looks like we’re posting from different time zones (I am in Australia, hence the blogname) so most of my posts will appear late at night US time.
I take your point about being interested in the early part of the record. I am more interested in the last decade, since I personally believe the current trend is strong enough to render any SD calculations moot.
Sphaerica (Bob) @ 150,
YES. That’s exactly what I was trying to describe earlier, but with the last 10 years coloured instead of just 2011. (And having a grey scale for earlier years is a nice touch.) :-)
157, John,
I agree 100% with Jim’s position. Stick to the facts, and to what is proven, not merely suspected.
The problem does not lie with the scientists, it lies with the politicians. It lies with those who believe in climate change (primarily U.S. democrats) that lack the will to actually make an issue of it. I like Obama as a president, but I’m very disappointed by the lip service he’s given to the issue.
The other side (primarily U.S. republicans) who are fighting against the issue are of course the most to blame, but it is not the fault of science that they are either blinded or bought out by their own political interests.
I do hope that I live long enough to (a) know that the problem is being properly addressed and (b) that the people who were on the wrong side of this in the critical years are taken to task for their indefensible position.
But the problem does not lie with the scientists, either in how or what they communicate. Jim’s position is the only one a scientist can take. I applaud Hansen for taking the stance that he does, but not all of them can do so, and even he must maintain his reputation first as a scientist, and second as an advocate. He does battle, but he does so only with science and what is provable. And certainly, they cannot all take that road, and be as outspoken as he is.
The day may come when a scientist abandons his profession to play foil to the Moncktons of the world, but I hope it doesn’t come to that. And if it is not going to come to that, pressure should be put not on the scientists but on the politicians, for those who understand the danger to act more aggressively and for those who don’t understand to wake up and admit to the truth of the matter.
Beating up on the scientists isn’t the answer, and it’s totally undeserved.
Didactylos @153. Thank you again for reply.
From what you say; do I understand that we do not have a measure of what the Arctic extent is supposed to be in our current environment?
I grew up in the 50’s and 60’s and remember that Arctic extent increased quite significantly around the middle of that century. We were also taught that wind and currents had a significant effect. I guess when my generation leaves you will have an easier time getting folks to adopt the current thinking.
Sea Ice Volume
http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2_CY.png?%3C?php%20echo%20time()?
152 Sphaerica (Bob): “I firmly believe that the answer is a whole lot of little solutions (behavior changes, like not all commuting at once, or restricting business air travel to what makes sense, more energy efficient buildings, more fuel efficient vehicles, alternative fuel sources, etc., etc.).”
Sorry, but that isn’t working so far. It is only creating irritation and a negative attitude toward environmentalism. If you get them angry enough, they will retaliate. Besides that, it is accomplishing nothing. It IS making people think that they are doing their fair share when nothing is being accomplished, another negative. “Believe” is an unscientific word. We have confidence levels, not beliefs.
The first wedge has to be a big one that the average person never notices, like outlawing power plants that add CO2 to the air.
“This is what I find most perplexing about deniers, that the very thing that they want to avoid — economic crisis and major lifestyle changes — are almost being forced on us by the unnecessary delay.”
You are assuming that they are being truthful about their motives. They are not being truthful about anything. Read “The sociopath next door : the ruthless versus the rest of us” by Martha Stout. New York : Broadway Books, 2005. Actually, chaos would be exciting, and they crave excitement in any form, because they care about nothing and nobody.
We need to make a new semi-political web site and blog, maybe a new political party, because RC wants to stay pure science.
Didactylos & Titus: The ice extent should be what it was in 1950. Why? Because the 1950s were years of plenty.
Hmmm. I’m with Jim on not saying stuff which we don’t have very strong reason to believe to be true. There are a significant number of “greenies” who are ready to believe any old tripe that fits in with their world view. There are an awful lot of “fake” skeptics who are the same with climate science – they will believe any rubbish which they believe disproves AGW.
Good solid arguments are diminished if followed by unsubstantiated assertions (except in the case of this sentence, despite it being an unsubstantiated assertion).
Barton 110.
I really liked your link and it is very interesting recap.
My comments were more related to Artic Ice estimation.
As you may know the NSIDC is production a competition between models, statistics and Heuristics to predict summer ice extent.
In the context of the predictions done by these experts I would like to know:
Who is the most/least (or order is even better) accurate at the first prediction?
As they go on doing many prediction, which is the improving in accuracy as time evolves?
Point is competition is great at first to stimulate all these guys to look fro alternative.
Now they would probably love to see some statistical measurements of their evolution.
After the goal is that the team of them is as perfect as possible.
I have a few concerns with the actual models…
Which ones has in it a good accuracy fro methane emitted from oceans?
Methane from pergelisol?
If we focus on CO2, we can easily measure the impact.
It is the domino effect that is tough to measure.
Decomposing all ingredients into separate impacts then rebuild the synergy with modeling seems to be the avenue some must have taken.
Again, here, I am just a newbie… (may be three posts in here).
I have some fundamental questions like:
Is there a model that predict an abrupt climate change?
Do we have models that can predict the number of cat 3+ hurricanes with 90% degree of certitude?
Someone must have think about this way before me so it must have been studied.
My post was too long… So it was identified as Spam.
I will try to post it in many parts: decompose and rule.
Sphaerica (Bob) @160
Is it proven that the models used for the current round of the IPCC negotiations underestimate climate change because they don’t include important feedback mechanisms? I’d say it is.
What would you say?
P.S.
My MP seems to have accepted DECC’s refusal to answer letters. The main question is “Why didn’t the Secretary of State know?” I can’t ask Huhne in person for a month or two. Anyone in the UK got an MP that might help?
P.P.S
I’m glad Jim’s closer to the sharp end of this struggle than I am.
Post 162 seems also to point to information about sea ice volume.
Intuitively, I do see that the ice cube in my glass is slow to melt at first but the volume seems to follow a kind of logarithmic (exponential or similar) spped of melting.
Just me looking at the ice cube in my glass… No real science here.
But if I use this intuition, I would expect that the same could happen in Artic, Groenland and Antartica.
As we are looking at great volumes, it must take longer to show that the preogression is not linear.
Now that I have put my questions in context, it is time to ask them:
– Is the melting of ice following a linear or a logarithmic function?
– When we had prediction of summer free artic sea in 2050, was it based on a linear progression?
– Are we starting to see logarithmic (or exponential cqn tell which is the good word but you get the feeling) melting?
– If such a function exists, what is the prediction for ice free summer: 2020? 2030?
(I read 2030 but again, I am skeptical, seems all study are underevaluating the progression of this…).
To me Artic ice is the canary in the mine shaft: really shows the pace we should expect.
Looking at winter ice is even more interesting.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.recent.arctic.png was previously posted.
What is the trend?
Between 2010 and 2011, we seemed to have lost about .7MKM2
How much time should it take to go from 13MKM2 to zero?
Any estimates? what is the pace since 2007 (after 2007)?
What is the pace since 1969?
Titus, that’s not what I said, and your memory is not reflected by the long-term records we have.
We have direct measurements of ice extent going back a century, and reconstructions going back thousands of years. As I have said repeatedly, all this data shows a relatively stable ice pack (until global warming intervened).
The last century
Two thousand years of polar temperatures
900 year Arctic ice reconstruction
Memory is an unreliable thing.
If you are interested in the environmental impact of slash and burn agriculture, such as global warming and deforestation, The Frontline Club is holding a screening tonight in Paddington of “Up In Smoke.”
Filmed over a period of three years across the globe, Up in Smoke follows pioneering scientist Mike Hands as he attempts to change one of the most carbon-emitting practices in the world: slashing and burning rainforests for subsistence agriculture.
Combining Hands’ scientific research with the lives of the impoverished farmers who depend on slash and burn agriculture for their livelihood, the film examines the real cost of carbon and the attempts to change environmentally damaging practices.
The core of the film is Hands’ attempts to put slash and burn agricultural practices on the agenda at the 2009 Copenhagen Summit and draw global attention to the issue. Up in Smoke shows the desperate working conditions of the farmers in South America and addresses the complex moral questions about the demands of saving the planet for the future and protecting the livelihoods of people living today.
The film is followed by a Q&A with the director, Adam Wakeling, and revolutionary ecologist Mike Hands, which should lead to a productive, informative, and essential discussion for any of those passionately interested in issues related to climate change.
For more information, please visit: http://www.frontlineclub.com/events/2011/07/screening—up-in-smoke.html
PAM, my crude understanding of what happens to an icecube is this:
It starts off at -18°C, straight out of the freezer or icemaker. If you drop it into a cold drink, then it won’t start melting much – the drink is already close to 0°C. Over time, the icecube will melt a little at the edges, keeping your glass cold. But also, the entire icecube will gradually warm up. When it reaches close to 0°C, the rest of the cube will melt fairly quickly.
I’m not sure quite how much of this transfers to Arctic sea ice. There are a lot of different melting processes going on.
Geoff Beacon:
I’m as concerned as you about the possibility of a clathrate gun effect or rapidly melting permafrost. However, climate models can’t incorporate detailed feedbacks until they are understood reasonably well.
Current observations show that a) clathrates are melting, and methane is bubbling already, and b) a lot of the methane is dissolving in the water, and c) it’s not yet a catastrophic event – the margin of bubbling is closely tied to ocean temperature and is moving slowly.
So, since all this ultimately leads to more CO2 and methane in the air, any potential short term effect is very likely to already be covered by the envelope of IPCC emissions scenarios.
John Pollack quoted Kevin Trenberth in comment #158 above:
Would all climate scientists who EVER speak to the public and/or the media about global warming please memorize that passage and repeat it at every opportunity?
Thank you.
We live on an anthropogenically warmed planet now. If you want to experience weather that is unaffected by anthropogenic global warming, you will have to go to another planet. Because there is no such thing any more on Earth.
WRT Didactylos’ graph at 115,
I have been thinking for some time that I wish NSIDC or whoever uses their data (or the ice-volume data as opposed to ice extent) would limit their multi-year graphs to a two-color scheme. A graph is inherently a visual tool; limiting the graph to gradients from one color to the other allows the reader to ‘see’ the overall pattern over time much more easily. (Unless they suffer reduced color vision, of course.)
Personally, I don’t care if it is yellow-orange or red-blue. Though, higher contrast might be desirable. Highest contrast would be between complementary colors, like green-red or blue-orange. Though, you might end up with some blah browns in the middle if you do that. On the other hand, the browns in the middle of the color change, but not in the middle of the progression of lines might be a good clue as to how the trend is accelerating. It would take some playing with to sort out the combination that pops the information in an instant.
It might even be enough to have one or more of the color pixels (red, green, or blue) vary from between min and max illuminations based on + * ( – )/. That would change the color as well as the brightness, which would make it work in greyscale as well. Mmm, an example:
Five years of data with only red changing, from 10% red to 90% red:
(Hex values of RGB in the form #RRGGBB)
#197F7F
#4C7F7F
#7F7F7F (mmm, that would be grey; not sure that is what we want)
#B27F7F
#E57F7F
Well, I can tell you’ve given it some thought, but maybe this will give you something to try if you haven’t already.
The only other way of avoiding the spaghetti look that I can think of offhand is to add a time axis and project the plot in 3-D.
167, Didactylos: 900 year Arctic ice reconstruction
Is it known why the Arctic ice extent was greater during the Medieval Climate Optimum than it is now?
PAM,
Mmm, I don’t know that a glass of ice is a good analogy for large ice masses, but…
If you stick a thermometer into a completely frozen block of ice in a glass, and set it out in an above freezing environment, what you will see is this:
There will be a relatively rapid rise, though nonlinear, up to the melting point.
The temperature will barely move (not at all in theory) as the ice goes through a phase state change to water. There is a lot more energy in water at 0 C than there is in ice at 0 C, and the increase in energy is reflected in the lower ice volume rather than a change in temperature. (Which is why in a survival situation, you should melt snow before drinking it if at all possible.)
Once all the ice is melted, there will again be a rapid rise in temperature.
So, I surmise that once the summer extent drops to zero, or near enough, we will see more rapid changes in the weather patterns than we have so far.
Bother, my pseudo-code at 171 must have gotten interpreted as HTML tags:
min + number_of_years_since_start * (max_illumination – min_illumination)/total_number_of_years
170, Secular Animist, and others before: “Given that global warming is unequivocal, the null hypothesis should be that all weather events are affected by global warming rather than the inane statements along the lines of ‘of course we cannot attribute any particular weather event to global warming’. That kind of comment is answering the wrong question.”
What is the value of the new null hypothesis (or a reasonable range)? The global temperature record shows one of the following:
a. steady rise of temperature at a constant rate, with an independent autocorrelated residual process;
b. alternations of warming and non-warming, with the warming epochs all displaying the same rate of warming.
An analysis published in Nature earlier this year, and featured on Real Climate, showed an increase in rainfall maxima in a large region of the U.S. of about 7% over about 50 years, or about 0.15% per year. Would you accept or propose that as a reasonable null hypothesis for future work (or a reasonable basis for formulating a prior for future Bayesian analysis)?
Worldwide, there is a slight increasing trend in total rainfall; would you propose or accept that trend line as a null hypothesis (or a basis for a prior)?
Trenberth’s comment is not inherently unreasonable, as to the phenomena of climate change, but it is vague.
Other long trends have been empirically revealed: decline in Arctic Ice, increase in Antarctic Ice, decline in total American tornado intensity, decline in global hurricane energy. Should we take the estimated trend lines for all of these measurements as null hypotheses?
It isn’t a bad idea, but it needs explication.
Septic Matthew,
What are you talking about?
a) the rise is more than linear
b) regardless of the warming rates, you are leaving off the periods of cooling, which are decreasing in rate and duration
Them there are a lot of fancy words, but your founding premises are simply wrong.
Septic Matthew: “Is it known why the Arctic ice extent was greater during the Medieval Climate Optimum than it is now?”
Global warming. Duh.
Didactylos @169
The clathrate gun may be another missing feedback but as you say, “climate models can’t incorporate detailed feedbacks until they are understood reasonably well” – but more prominence should be given to what is omitted.
However, my main comment was not on missing methane feedbacks but the carbon dioxide that is being released by melting tundra as discussed by Schaefer et. al.
I think that is a feedback that is much better understood. Do look at the Open Letter to Chris Hunhe mentioned earlier for Kevin Schaefer’s comments.
Yeah personally, I’d rather prefer to have it proven to me unequivocally how a given weather event can’t be affected by AGW.
Scientists have to be careful about how they advocate or engage politically, but that shouldn’t stop them from complaining strongly about dilly-dallying, or even what amounts to criminal neglect of the problem.
Edward Greisch @ 151
Reminds me of the Old English poem “The Wanderer” (there are lots of better translations on the net than I can devise):
64-77
Forþon ne mæg weorþan wis wer, ær he age
wintra dæl in woruldrice. Wita sceal geþyldig,
ne sceal no to hatheort ne to hrædwyrde,
ne to wac wiga ne to wanhydig,
ne to forht ne to fægen, ne to feohgifre
ne næfre gielpes to georn, ær he geare cunne.
Beorn sceal gebidan, þonne he beot spriceð,
oþþæt collenferð cunne gearwe
hwider hreþra gehygd hweorfan wille.
Ongietan sceal gleaw hæle hu gæstlic bið,
þonne ealre þisse worulde wela weste stondeð,
swa nu missenlice geond þisne middangeard
winde biwaune weallas stondaþ,
hrime bihrorene, hryðge þa ederas.
112b-114a
ne sceal næfre his torn to rycene
beorn of his breostum acyþan, nemþe he ær þa bote cunne,
eorl mid elne gefremman.
Chris G: Complementary colours actually often result in lower contrast, because even if the hue separation is greater, the separation in brightness can be far, far lower.
I try not to over-think things in terms of making allowances for various forms of colour-blindness, but I try to make sure there is always reasonable brightness contrast so that the hues don’t matter.
I tried the 3D thing a while back, and was disappointed. It’s hard to communicate relative height in 3D, and the trend is subtle enough that the whole thing was just a mess. Maybe I just didn’t find the best way to present it.
I’m happy to share my code if anyone wants to try their favourite colours.
Didactylos, Septic,
I was going to say that might be an indication that either, or both, the MWP was not as warm as it is now, or it was not global in nature.
You shouldn’t put too much weight into any one study. You kind of have to survey the field and proceed as though the truth were somewhere within the majority that are consistent with each other. The finding that ice extent was higher during the WMP is consistent with the majority of findings that it was neither as warm globally nor at the same time in different parts of the world, as it is today. It is inconsistent with the minority which hold that it was global and warmer. There is some danger of confirmation bias in this method, but as long as you are willing to re-assess your viewpoint in light of new information, that danger is minimal.
So, you should take the paper’s finding that sea ice extent was greater during the MWP to be in support of that period not being warmer than today rather than take it to mean that there must be something wrong with the paper because it is inconsistent with the minority position that the period was global and warmer.
Minorities are sometimes correct, but it isn’t the way to bet.
Didactylos @ 180
The image isn’t coming up for me, but FWIW and if it’s really an issue, a starving artist might be able to subtly and effectively tweak additional visual variables in combination for you (hue, saturation, value, line weight, line texture, and perhaps transparency) using other software, and do it in ways that aren’t obstructive to meaning — within limits of course.
Chris G, the study doesn’t say that “ice extent was higher during the WMP” – it says the opposite.
Is there some other study that says otherwise?
Didactylos,
All true.
What about a dark, say red, to a bright yellow? Color-wise, that would be stepping red down while stepping blue and green up, something like
#0A0000
…
#00FFFF
Just thinking. I wonder if a human factors expert could offer some suggestions. Or, better, if some climate researcher at a university could get together with some human factors person in the cognitive psych department. If they come up with something good, then others will emulate. That would be a neat ‘trick’.
I found this, which looks like some good starter material, but limited.
http://www.visualexpert.com/FAQ/Part5/cfaqPart5.html#p5.11
Quite a clear view of the ice on the Siberian side of things today. Nick Barnes, if you’re reading: the holes you were looking for are starting to show up.
The (multiyear) ice in the Beaufort is taking a beating, the ice in the East Siberian Sea is brown and grey, the ice in the Laptev Sea is being torn apart by that low-pressure system, the ice in the Northwest Passage AND the channels in the Canadian Archipelago is disintegrating (multiyear ice from the Arctic Basin is going to board the train soon), while ice in the Greenland Sea is slowly being pushed towards Fram and Olga Strait (and then lower latitudes).
Man, this is exciting! What a melting season!
Didactylos #183,
I missed a ‘not’, as in, ‘_not_ greater’, at comment #181.
It’s only an apparent disagreement, not a real one.
OK, I’m over-thinking the graph problem, but here goes…
The physical material that is being represented is ice and water. That naturally lends itself to using a white-blue color scheme, but white would only work on a black background. Plus, different colors represent different years, not varying amount of ice versus water. While using this combination would amplify the perception of the existing trend, it could be construed to be a ‘trick’ of the deceptive kind rather than a ‘trick’ of the clever kind. Plus, a darker blue will perceptually appear to be ‘further away’ than a lighter blue; so, if one uses lighter colors when there is more ice, there will be a dissonance between perceived distance in space and actual distance in time. Further away in time will appear closer in space.
Any major hue change crosses a grey area. This could be good or bad. It would convey a midpoint in time, but could also convey a meaning of a neutral time, which might be confused with a baseline average, which it would not be.
The fact that light colors tend to appear closer than dark colors could still be used to as a time analogy. But, the darker colors should represent years farthest back in time.
We are still talking about ice and water; so, personally, I’d go with blues and/or greens.
OK, my two cents, if it were me, I’d go with something like a navy blue transitioning to a cyan:
#000080
…
#00FFFF
http://www.tayloredmktg.com/rgb/
(Yeah, I goofed; 00ffff (above) is cyan; yellow is ffff00.)
ach, #186, errata,
“Our results suggest that as of 1985, Arctic summer sea ice cover extent dropped below the lower bound of the reconstructed minimum for the Medieval Warm Optimum (ca AD 1150). ”
If it is now below the lower bound minimum of the reconstruction, then it was greater during the MWO reconstruction than it is now. I think one of us is misreading the other.
I have updated the East Siberian Sea animation. Finally a relatively clear picture. The difference is absolutely stunning.
181, Chris G.: So, you should take the paper’s finding that sea ice extent was greater during the MWP to be in support of that period not being warmer than today rather than take it to mean that there must be something wrong with the paper because it is inconsistent with the minority position that the period was global and warmer.
Isn’t it accepted that the MWP applied to the Northern Hemisphere generally? The reconstructions mostly put the MWP warmer than now, but they are merely reconstructions, and as you say, they may be in error.
OK, still over-thinking…
Probably been thought of before, but aggregating over 4-6 years might smooth out the inter-annual variability enough to make the trend easier to see, both for a color graph and a 3-D graph. That would obviously loose some detail, but I’ve learned that messages, especially to pointy-hair boss types, are more persuasive when they are less obscured by details; so, it depends on the target audience.
Santa.
If we reach another ice minimum this year, or whenever, and the ice-free North Pole is real, even if only for a short time in summer, Santa will be the new ambassador of Climate Change. He’ll start as a summer joke meme – where does his house go? Are the elves Mer-men? – but he’ll be remembered a few months later at the holidays. And the culture will shift…
I have made an animation of the Canadian Archipelago.
Quote from the post:
“Up till now that multiyear ice that was pressed against the Canadian Archipelago had something to press up to. But as we saw in the first half of August last year all of the ice in those channels started breaking up and multiyear ice was transported from the Arctic Basin to lower latitudes where a lot of it melted out. Some of it froze up in the Northwest Passage, which could be a reason the passage is a bit slower in breaking up than it was last year.”
Needless to say, this is a very important area to keep an eye on.
> Isn’t it accepted that the MWP applied to the Northern Hemisphere generally?
Why would you think that?
http://www.google.com/search?q=site%3Aipcc.ch+medieval+warm
Just reading this thread shows the difficulty inherent in trying to disseminate accurate scientific findings. Titus, in #161 says:
Didactylos in #170 ‘corrects’ Titus:
And Didactylos even provides a link to a graph of the previous century’s Sea Ice Extent. But the graph DOES show a peak in sea ice extent in 1953. So Titus’ memory isn’t all that bad. Of course the peak in extent correlates to a regional and global drop in temperature. That SIE increased briefly is hardly a surprise.
While it did increase in the early 1950’s, I’m not sure we could categorize it as ‘significantly’ – the data has plenty of uncertainties given the reanalysis methods. On the other hand, many skeptic sites have photos of submarines surfacing at the North Pole in the 1950s … to their minds ‘proving’ there was LESS ice in the Arctic as recently as the late 1950s. There is NO support for that view.
Titus goes on to say:
I’m a bit skeptical here myself. I’m only a few years younger than Titus and the only time I even remember the Arctic being mentioned is when the Manhattan sailed across it. Unless you were an oceanographer specializing in the Arctic Ocean it was not a topic of conversation. The gratuitous jab at ‘kids these days’ is misplaced. We know far more about the effects of wind, currents, and a whole host of other weather and climate-related variables and how they effect sea ice transport, extent, area and volume than at any time in human history. Climate scientists today not only consider all these variables (including wind and currents) they are able to quantify them. To believe that somehow more was known about the Arctic 60 years ago is nonsense.
Northern Hemisphere only – I don’t have a firm belief one way or the other. My understanding is that evidence in the south is harder to find than evidence in the north.
Broeker says global – http://www.sciencemag.org/content/291/5508/1497.short
Villalba says also in SH, but the timing is odd; there is a cool spell there when there is a warm spell in the NH, according to some others – http://www.springerlink.com/content/x0214563n1n44731/
Mann (2008) seems to find something happening in the SH, but not clear to me that it coincides with what was happening in the NH –
http://www.pnas.org/content/suppl/2008/09/02/0805721105.DCSupplemental/0805721105SI.pdf
Timing and location – If memory serves, timing of the peak is an issue; from as early as ~850 AD to as late as ~1150 AD. That’s quite a bit of variance for a period only 3-4 hundred years long to begin with. It’s there in most records, just not everywhere at the same time. I have no real idea why that would be; maybe shifts in ocean currents? A little more heat here, a little less there. Currents can do that.
Generally warmer than today – not according to the majority of papers I’ve had a chance to look at. Then there are also the sea ice reconstructions which show extents lower in recent decades and the algae that disappeared from the Atlantic 800,000 years ago and have only recently been found again in the North Atlantic. Best guess is they came across the Arctic ocean from the Pacific.
Here is, not an actual paper, but a summary of several:
http://skepticalscience.com/print.php?n=394
Santa will be the new ambassador of Climate Change.
Santa. Right. Sure. You could try reality. It works for me.
Chris G at # 173:
Lower ice volume? This seems to contradict that water is denser then ice.