Guest Post by Willis Eschenbach
There’s an old con game that has been played on the suckers for hundreds and hundreds of years. It is done in various forms, with various objects, under various names—three card monty, the shell game, Thimblerig, bottle caps, cups and ball, the game is the same in every one. The essence is, the con man puts a pea under a shell, then switches the shells around and asks which shell is hiding the pea.
Figure 1. The Conjuror, by Hieronymus Bosch, painted 1475-1480. The type of tricks the conjuror is doing are thought to be among the origins of the shell game.
I bring this up because our favorite conjuror, James Hansen, is up to his old tricks again. He has a new paper out, Paleoclimate Implications for Human-Made Climate Change, And as always, you have to figure out which shell is hiding the pea.
Here is his money graph, the one that is getting lots of play around the blogosphere. The main observation I’ve seen people making is that having been bitten by previous failed prognostications, Hansen is taking the well-tested Nostradamus route now, and is predicting sea level rise for when he’ll be 137 years old or so …
Figure 2. Hansen’s Figure 7: ORIGINAL CAPTION: “Five-meter sea level change in 21st century under assumption of linear change and exponential change (Hansen, 2007), the latter with a 10-year doubling time.”
Folks are saying that the bad news is, it looks like we won’t be able to tell until 2040 or so if Hansen’s claim is true. But that’s not the case at all. Those folks are not keeping close enough watch on the pea.
In the paper Hansen says:
Sea level change estimates for 21st century.
IPCC (2007) projected sea level rise by the end of this century of about 29 cm (midrange 20-43 cm, full range 18-59 cm). These projections did not include contributions from ice sheet dynamics, on the grounds that ice sheet physics is not understood well enough.
Rahmstorf (2007) made an important contribution to the sea level discussion by pointing out that even a linear relation between global temperature and the rate of sea level rise, calibrated with 20th century data, implies a 21st [century] sea level rise of about a meter, given expected global warming for BAU greenhouse gas emissions. …
… Hansen (2005, 2007) argues that amplifying feedbacks make ice sheet disintegration necessarily highly non-linear, and that IPCC’s BAU forcing is so huge that it is difficult to see how ice shelves would survive. As warming increases, the number of ice streams contributing to mass loss will increase, contributing to a nonlinear response that should be approximated better by an exponential than by a linear fit. Hansen (2007) suggested that a 10-year doubling time was plausible, and pointed out that such a doubling time, from a 1 mm per year ice sheet contribution to sea level in the decade 2005-2015, would lead to a cumulative 5 m sea level rise by 2095.
The short version of that is:
• The IPCC predicts sea level rise of about a foot (30 cm), but they don’t take ice into account.
• Rahmstorf says a linear projection gives about a metre (3.3 feet) of sea level rise.
• Hansen 2007 says there’s a missing exponential term in Rahmstorf’s work, because the ice will be melting faster and faster every year.
OK, so Hansen 2011 rests on the claims made in Hansen (2007), which turns out to be Scientific reticence and sea level rise. At the end of Section 4 Hansen says that Rahmstorf estimates a 1-metre sea level rise, but that a non-linear ice melting term should be added to the Rahmstorf rise.
Under BAU [“Business As Usual”] forcing in the 21st century, the sea level rise surely will be dominated by a third term: (3) ice sheet disintegration. This third term was small until the past few years, but it is has at least doubled in the past decade and is now close to 1 mm/year, based on the gravity satellite measurements discussed above. … As a quantitative example, let us say that the ice sheet contribution is 1 cm for the decade 2005–15 and that it doubles each decade until the West Antarctic ice sheet is largely depleted. That time constant yields a sea level rise of the order of 5 m this century.
So to get the final Hansen projection, we need to see what is happening in Rahmstorf, A Semi-Empirical Approach to Projecting Future Sea-Level Rise, paywalled, where we find the following graph of projected sea level rise.
Figure 3. The Rahmstorf estimate of sea level rise, to which Hansen says an exponentially growing ice term should be added.
ORIGINAL CAPTION: Past sea level and sea-level projections from 1990 to 2100 based on global mean temperature projections of the IPCC TAR. The gray uncertainty range spans the range of temperature rise of 1.4° to 5.8° C, having been combined with the best statistical fit shown in Fig. 2. The dashed gray lines show the added uncertainty due to the statistical error of the fit of Fig. 2. Colored dashed lines are the individual scenarios as shown in (1) [Ref. 1 is the IPCC TAR Bible, no page given]; the light blue line is the A1FI scenario, and the yellow line is the B1 scenario.
(In passing, let me again protest the use of the entire IPCC Third Annual Report, thousands of pages, as a reference without giving us chapter and verse in the way of page numbers. My high school science teacher would have slapped my hand for that, it’s a joke.)
The upper blue line is the one that gives us about a meter of sea level rise. So I took that as Rahmstorf’s 1 metre rise. To that I added, as Hansen claims we should, an amount that starts at 0.5 cm in 2000 and doubles every ten years. This is following Hansen’s claim that the non-linear ice disintegration is a separate term that starts small but will “come to dominate” the sea level rise over the century. The result is shown in Figure 4.
Figure 4. Rahmstorfs predicted rise (blue), Hansen’s projected additional rise from “non-linear ice disintegration” (dark red), and total sea level rise (green) predicted in H2011. I have included the last century’s rise of 16 cm, as calculated by Rahmstorf, in the lower right corner for comparison purposes. IMAGE SOURCE
OK, so what Hansen is actually predicting is the green line. However, his real forecast is actually much worse than that. Hansen again, emphasis mine:
The eventual sea level rise due to expected global warming under BAU GHG [greenhouse gas] scenarios is several tens of meters, as discussed at the beginning of this section.
I’m going with “several tens” to mean more than two, so he’s predicting a 30 metre sea level rise!!! … I guess he figured nobody paid any attention when Al Gore threatened us with a 20 metre sea level rise, so he’d better pull out all the stops and give us a real scare, something to make us shake in our panties.
There is a bit of good news, however. Both the Rahmstorf and the Hansen projections are already way above the reality. Since 1993, when the satellites started measuring sea level, we’ve gone up about 4.6 cm (1993-2011). Rahmstorf’s projection is 6.4 cm for that time period, about 40% too high already. Hansen’s larger projection is 7.2 centimetres rise over that time, or 55% too high.
The annual rise is also entertaining. According to the satellites, the trend 1993-2011 was 3.2 mm/yr, and has been declining recently. The change 2009-2010 was under a mm, at 0.9 mm/yr. And 2010-2011 was just about flat.
In 2010-2011, Rahmstorf’s projected rise is already 4.5 mm/yr, about fifty percent larger than the actual rate of the last 18 years. And Hansen’s annual rise is even worse, at 5.3 mm per year.
So both in terms of 1993-2011 rise, as well as current annual rise, both Rahmstorf and Hansen are already way above observations. But wait, there’s more.
Hansen’s rate of sea level rise is supposed to be accelerating, as is Rahmstorf’s rate. By 2020 Hansen says it should be rising at 6.3 mm per year, and everlastingly upwards after that. But in fact we’re already way under their supposed rates of annual increase, and the observed rate of rise is declining …
How does Hansen get these nonsensical numbers? Well, he noticed something in the observations.
This third term [melting ice] was small until the past few years, but it is has at least doubled in the past decade …
My high school science teacher, Mrs. Henniger, bless her, thought extending a linear trend into the future was a crime against nature, and I would hesitate to express her opinion on Hansen blithely extending a ~ 7% annual increase for a hundred years. That kind of compound interest turns a centimeter (3/8″) into 5 metres (16 feet). If Dr. Hansen had submitted this nonsense to her, you would not have been able to read it when it came back for the red pencil scribbles.
You can’t do that, folks. You can’t just observe that something has doubled in the last decade, and then extend that exponential growth out for a century. That’s beyond wishful thinking. That’s magical thinking.
Two final points. First, the pea under the walnut shells. Note carefully what Hansen has done. He has claimed that the sea level rise will be “several tens of metres”. This is at least thirty metres, or a hundred feet, of sea level rise.
He seems to be at least somewhat supporting this claim with his Figure 7 (my figure 2). But if you look at the caption, this is not a forecast, a projection, or a scenario of any kind. Instead, this is merely an “approximation” of what a linear sea level rise might look like and what an exponential rise might look like. You know, in case you didn’t understand “linear” and “exponential”. His actual forecast is under another walnut shell somewhere. We know his “Approximation” can’t be a real projection because it shows almost no rise occurring currently, or for some years.
Second, even this doesn’t begin to unravel the errors, deceptions, alarmism, and con games in Hansen’s work. Do you see the guy in the dark vest and the white pants and shirt at the left of Hieronymus’s painting at the top? See what he has in his hand while he’s looking all innocent at the sky? See who it’s chained to? Hansen’s not really the shell game conjurer, that guy’s a piker, he’s not making much money on the game.
Hansen’s the guy in the dark vest with his hand on your pocketbook …
w.
[UPDATE]
Joel Shore observed correctly that Hansen was basing his estimate of a huge sea level rise on paleoclimate date. Joel is right that Hansen claimed the paleoclimate data shows a rise of 20 metres for every 1°C temperature rise. Because of this, Hansen says that a 2°C future temperature rise will give a 40 metre sea level rise.
Let’s take a bit calmer look at what we know. We know that when there is an ice age, a lot of the water in the ocean behaves badly. It goes up on the land as mainly northern hemisphere ice and snow and glaciers. As a result, the sea level drops by a hundred metres or so. The glaciers stay there until the ice age ends, at which point they melt, and the sea level rises again. Since we’re in an interglacial, right now the glaciers are mostly melted.
So I would certainly not expect further warming to have much effect on melting or sea level. The easy ice is all melted, the giant miles-thick Northern Hemisphere glaciers are almost all melted back into the ocean. The rest are hiding mostly on north slopes in northern climes. So where is the meltwater going to come from?
And curiously, what I found out from Joel’s question is that if you know where to look, we can see that the graphs in Hansen’s own paper bear me out. They say the oceans won’t rise. I don’t particularly believe Hansen’s results, but presuming that they are correct for the sake of discussion, then let’s look at his graphs.
Look first at the sea level during the past four interglacial periods. I stuck a ruler on it so you can see what I mean.
As you can see, at the level of detail of their graph the sea level has never been higher than it than it is now.
Now look at their temperature observations and reconstruction:
According to Hansen, temperatures have been as much as 2.5°C higher than at present … but the sea level hasn’t ever been higher than at present.
If Hansen’s claim were true, that a 1°C temperature rise leads to a 20 m sea level rise, we should see sea levels forty metres or more above present levels in Hansen’s graph (b). Look at the scale on the left of graph (b), that’s off the top of the chart.
Instead, we see nothing of the sort. We see much warmer periods in the past, but the sea levels are indistinguishable from present levels. Hansen’s own graphs show that he is wrong. So it appears that Hansen is doing the same thing, he’s extrapolating a linear trend out well beyond the end.
He’s noticed that when warming temperatures were melting the huge glaciers over Chicago, the sea level rose quickly. Unfortunately, he has then extended that trend well past the time when there are no glaciers in Chicago left to melt …
w.
Being a cynic and having a healthy contempt for the intentions of our so called ‘political elite’, I am inclined to think Hansen was told by some lefty/greenie politician: “You have got to be more scary, or you’re toast. Don’t worry about the facts, or logic, just remember it’s all for The Cause.”
Willis has quite correctly and simply shredded Hansen’s logic, which now begs the question:
Hansen – fraud, or incompetent?
Either way, he is a serious waste of tax dollars.
Maybe it ‘s because it’s Monday morning and I’m being a bit slow, but this simple extrapolation of the data, by whatever means can’t be right, can it?
At some point the *physical mechanism* for melting ice will change, when all the sea ice has melted and there only remains the ice sitting on Greenland or Antarctica … This is ice which is not in contact with warming water. …
Hansen would need some new function to describe what happens after that, not just a simple continuation of what happened up until then.
A couple of qualifications on what scepticism actually means, to clarify a confusion A Physicist introduced. Yes, it’s important to have an open mind as a sceptic but not so open that your brain falls out (so the saying goes). The other principle to note is that extraordinary claims require extraordinary evidence.
Willis, you need to be careful.
That’s two papers recently with gambling analogies.
Next thing, The Team will be accusing you of being a compulsive gambler.
Hansen really has hit upon a winner: since it ‘is’ exponential:
1) It follows that only a tiny portion of that which WILL come is visible in here and now;
2) and ONLY the experts are capable of separating the signal(s) from the noise. Only they have the experience and expertise: bravely mixing model and measurement.
3) We MUST act NOW; once the exponential starts taking off, we is all are going to be a DOOMED peoples!!!
Strangely enough, the above makes a macabre kind of sense… 😉
…but perhaps that is always true when cherry-picking what to exclude from consideration.
RealPhysicist says:
January 29, 2012 at 11:39 pm
Actually, I was pretty unaware of it. I generally avoid anything by Rahmstorf, he is no respecter of facts. Thanks for the info, good stuff.
w.
“Who, I wonder, will go to jail over this massive multi-billion dollar fraud of the taxpayer?”
Of more significance is that the bastards are driving anti-development in the 3rd world. Poverty kills.
The question is rather if the hippies will EVER be made to pay for the evil they have wrought in this world: the total-ban on DDT (versus the partial) is always good to point out, since it is ongoing: the hippies dare not admit that that their (sorry, ‘the’) ‘science’ was both corrupted then AND now – it would cost them credibility. Credibility which they need to ‘save’ the Earth…
How many of you are willing to do that one little simple thing which the facts demand: alter the way you look at them, and then act accordingly, generally. Anyone?
What about partial-birth abortion? Or the more amusing live-birth abortion that Obama was so… bored with.
It is one thing to say that for evil to prosper, good men must do nothing; but when nobody even wants to use the word ‘evil’, because it would ‘hamper dialogue’…
Bleh. Too much d@mned moralizing, too little cognizance.
Personally, I can’t hardly wait for doomsday, and an end to all this: humanity has shown that it is worth nothing.
Whereas nowadays ordinary folks are making the NW Passage in rowboats, kayaks, and inflatable rafts.
And the aid of accurate charts, weather information etc.
Just for the record, it is easier make the NW passage in a rowboat or inflatable than a sailing ship, rather than harder. They have a much shallower draft and will rise above ice, rather than be crushed. Distance is not an issue – the Atlantic is no smaller than it ever was, and they row across that these days.
Sailing it blind (no GPS, no radio) like they did in the old days would still be tantamount to a suicide wish.
When the NW passage opens for commercial shipping, without ice breakers, then it is an open passage.
Willis Eschenbach:
You, Won.
Willis, back in May 2011 WUWT posted on the 0.3mm yr sea level adjustment. Whether this affected the trend was a matter of discussion in the comments but as far as I could see, never fully resolved.
These two comments from the original WUWT post seem like a reasonable summary of both positions. Any chance you could make a ruling on this one?
OldOne says:
May 6, 2011 at 6:38 am
Buzz Belleville says:
May 6, 2011 at 5:32 am
You do understand, fellow posters, that the Colorado page is not just adding 0.3 mm to the current year to show a greater rise in sea levels. It’s adding 0.3 mm to all plotted points. It has no effect on the rate of rise.
Buzz, per their website, the GIA adjustment was “-0.3 mm/yr. That’s per year.
The most recent ‘pre-adjusted’ data point for 2010.7415 was 28.119 mm.
This ‘post-adjusted’ data point for 2010.7415 is now 36.996 mm.
So you’re correct that they didn’t just add 0.3 mm to the current year, they added 8.877 mm to the most recent common data point
It does affect the rate of rise!
Hansen is saying that the rate of rise of sea level (i.e. the rate of volume increase increase of the oceans) has a linear component, due to thermal expansion of the oceans(?) and an exponential component due to ice sheet melting. He then goes on to claim that the latter cannot be verified because there’s insufficient data on the melting of the ice sheets, which he takes from mass gravity neasurements. But the hypothesis can also be tested by simply ploting logarithm sea level versus time. Why hasn’t he presented us with such a graph?
It might be of some interest to see if Hansen’s prophecies are actually physically possible.
The total amount of water in icecaps is equal to about a 70 meter increase in sea.level. Of this about 5-7 meters are each in the Greenland Ice Sheet (GIS) and the West Antarctic Ice Sheet (WAIS). The rest is in the East Antarctic Ice Sheet (EAIS). All others can be safely ignored, since together they are far less than the uncertainty of the three main ice-sheets.
Of the three main sheets only the WAIS is amenable to the famous “dynamic effects”.
The GIS is in a shallow bowl surrounded by mountains and only reaches the sea at the head of a number of fiords and along three or four short stretches of coast in the far north. Once it has retreated inland from these coasts, it can only sit still and melt in place which is a slow process, even in a warm climate (proven by the Scandinavian Ice Sheet, which took 2000 years to melt during the warmest part of the Holocene, when climate was appreciably warmer than it is today in Scandinavia). Incidentally not even the southern dome of the GIS did melt completely during the previous interglacial when temperatures were c. 5 degrees warmer than now in the area.
The WAIS is mostly based below sea level and can theoretically “calve out” if sea-levels and/or temperatures rise enough to raise the edges of the ice-sheet so that sea-water can flow in underneath the ice. Indeed this process has probably been going on (slowly) in the Ross Sea area ever since the end of the last glaciation.. The “WAIS collapse scenario” is very popular in CAGW circles, and is frequently referred to as an incontrovertible fact during previous interglacials, especially MIS 5e and MIS 11. However there is essentially no empirical support for this. There is definitely ice older than MIS 5e in West Antarctica and the AND-1B drill-core in the Ross Sea shows conclusively that the last time the WAIS may have collapsed was during the “double interglacial” MIS 31/33 about a million years ago. Such a collapse can by the way only be partial, since there are extensive mountain ranges (up to 17,000 feet high) in West Antarctica, and ice-caps would certainly survive on these.
The EAIS lies on a large Precambrian shield, either above or just below sea-level. It is not amenable to “dynamic effects” except perhaps locally in the Prydz Bay area, since the sea is nowhere else deep enough to raise the ice-sheet (since sea-water is only about 10% denser than glacier ice, the sea at the ice-front must be deeper than 90% of the ice thickness for this to be possible). The EAIS in short can only melt in place, from the top down, which would require extreme warming (several tens of degrees) and many millennia.
So what is the extreme physical limits of “dynamic effects”? I would say less than 10 meters of sea-level, counting part of the GIS, most of the WAIS and some minor effect on the EAIS. To judge from ice-core data this would at a minimum require temperatures >5 degrees centigrade warmer than at present on Greenland, and >10 degrees in Antarctica, and to judge from similar occurrences in the past (e. g. Heinrich events) it would happen on a millennial to multi-millenial time-scale.
Please have a look at the measurement data:
http://www.aviso.oceanobs.com/en/news/ocean-indicators/mean-sea-level/products-images/index.html
How to explain the last 2 years? Exceptions to a valid rule or unvalidation of a rule?
A physicist,
If you are indeed a real physicist I would ask you to resolve some of the real mysteries of physics. Personally I have been waiting for more than half a century for the concensus science of physics set in concrete around 1920 to tell me and the world the nature of magnetism, electricity and gravity, to name just a few.
Clever practical engineers have given us our modern world based on the manipulation of the properties of these things. Physicists invent theories and every one must follow, when it fails they invent more particles or as I would call them imaginary friends, to make the theory work.
Of recent times it was discovered that the universal model was missing almost everything, so they invented dark matter, this was not enough so they invented dark energy. This is the way of concensus science as it is prohibited to disbelieve the concensus.
In the same way that billions of dollars have been wasted, smashing a ball of energy into another ball of energy and analysing the debris and calling them particles with charm and spin and up and down looking for a god particle is as much madness as throwing billions at AGW.
I therefore request that you as a physicist explain to us what magnetism is, and why it has such magical properties that seem to extend through our solar system, and, probably the entire universe.
I expect Prof. Nils Axil Morner is laughing himself onto the floor. So much alarmist rubbish from a non expert in sea levels.
The latest sea level measurement gives a 5mm drop, due most probably to ocean cooling, and polar ice continues to build. I think James H should go away and revise his estimates.
One of the stocks in my portfolio doubled in value this week.
By this time next year, therefore, I will be richer than George Soros, Bill Gates and the Sultan of Brunei combined.
Those bastards at Boeing are being a bit funny about taking the order for my personalised 747 though.
Would any one care to give me what the expected trend is for this graph. http://www.aviso.oceanobs.com/en/news/ocean-indicators/mean-sea-level/products-images/index.html
Just for next year/six months even!
Sorry should have added, Time series, Global, Reference, Not Removed, Not Applied as the options on the graph just to get the raw underlying data.
tty, thanks for the extra information. Very interesting and educational. Pity Hansen will not read it.
Arguing with some alarmists is like arguing with the cartoon man who thinks he is Napoleon. Nothing can divert him from his conviction. He has been driven to distraction by it: ‘Why can’t people see the truth?’ ‘Why do they keep telling me I am someone else?’ ‘What are they up to?’ ‘Perhaps I have not yet made it clear enough who I really am?’.
Yet add to the cartoon another few panels showing that a great many people in positions of power are behaving as if they really do believe the man is Napoleon, and are making policies based around it. Here is where the arguments might be better addressed. Cool reason and insightful data analysis will not deflect our man, but they may yet unsettle those in power.
Thank you for another good piece of work.
lateintheday says:
January 30, 2012 at 1:27 am
No ruling, but some comments. First, my understanding is like yours. They did not just add 0.3 mm to all records, it wouldn’t make sense. That’s identical to just resetting the anomaly level. They added a trend of 0.3 mm yr-1. It did change the trend.
Second, I didn’t like the adjustment. It is sketchy enough already comparing tidal records with satellite records. Changing the satellite records alone seems very odd. I have also never heard a reasonable explanation why you would only adjust one and not the other. I mean, if the bottom of the ocean floors are sinking, which is the reason they give for adjusting the satellite records, why not the make the same adjustment for the tide gauge records?
But if you are making the adjustment to both, it hardly seems worth it. I mean, it distorts the actual measurements. So you have to subtract it back out if you want to see how much it will rise on a seawall or something. Overall, it just smells wrong to me. I don’t see the justification.
Third, the story is far from complete. Yes, we have 19 years of records, which at least is one lunar cycle. But really you need fifty years of records to decipher sea level. One of the surprising findings of the satellite sea level records for me is that sea level of large areas of the ocean can be rising over a decade while another large area is falling over the decade. This decadally slow sloshing back and forth of the water in the ocean basins distorts the sea level situation.
Best to you,
w.
No need for complexity. Plain fact: NOTHING in the real world is purely exponential. Some patterns have an exponential-looking part during the short time when we’ve been observing, but they later bump into a saturating ceiling and look like a tanh. Others may look exp’y for a while, but turn out to be a sine.
Anyone who claims that a real process runs linearly to infinity or exp’ly to infinity is a-priori wrong.
If these guys were real sceintists — without superhuman agendas — the interesting question to ask would be why such a small temperature rise in the latest cycle has resulted in a historically maximal sea level change. BUt seems focussing on that would have to explain unprecedented higher sea levels. IMO that is the pea that is being hidden.
thanks for that Willis – it’s been bugging me all year.
From Velicogna 2009, the paper cited by Hansen as evidence of an accelerating melt rate for the ice caps:
“The best fitting estimate for the acceleration in ice sheet mass loss for the observed period is -30 ± 11 Gt/yr2 for Greenland and -26 ± 14 Gt/yr2 for Antarctica. This corresponds to 0.09 ± 0.03 mm/yr2 of sea level rise from Greenland and 0.08 ± 0.04 mm/yr2 from Antarctica.”
So the total ice cap melting should be accelerating rate of sea level rise by 0.17 mm/yr2. Has anyone looked at the sea level data to provide some check on the Velicogna findings?