Inconsistencies may undermine model’s reliability for projecting decade-to-decade warming and lead to misinterpretation of data
DURHAM, N.C. — A new Duke University-led study finds that most climate models likely underestimate the degree of decade-to-decade variability occurring in mean surface temperatures as Earth’s atmosphere warms. The models also provide inconsistent explanations of why this variability occurs in the first place.
These discrepancies may undermine the models’ reliability for projecting the short-term pace as well as the extent of future warming, the study’s authors warn. As such, we shouldn’t over-interpret recent temperature trends.
“The inconsistencies we found among the models are a reality check showing we may not know as much as we thought we did,” said lead author Patrick T. Brown, a Ph.D. student in climatology at Duke’s Nicholas School of the Environment.
“This doesn’t mean greenhouse gases aren’t causing Earth’s atmosphere to warm up in the long run,” Brown emphasized. “It just means the road to a warmer world may be bumpier and less predictable, with more decade-to-decade temperature wiggles than expected. If you’re worried about climate change in 2100, don’t over-interpret short-term trends. Don’t assume that the reduced rate of global warming over the last 10 years foreshadows what the climate will be like in 50 or 100 years.”
Brown and his colleagues published their findings this month in the peer-reviewed Journal of Geophysical Research, at http://onlinelibrary.wiley.com/enhanced/doi/10.1002/2014JD022576/.
To conduct their study, they analyzed 34 climate models used by the Intergovernmental Panel on Climate Change (IPCC) in its fifth and most recent assessment report, finalized last November.
The analysis found good consistency among the 34 models explaining the causes of year-to-year temperature wiggles, Brown noted. The inconsistencies existed only in terms of the model’s ability to explain decade-to-decade variability, such as why global mean surface temperatures warmed quickly during the 1980s and 1990s, but have remained relatively stable since then.
“When you look at the 34 models used in the IPCC report, many give different answers about what is causing this decade-to-decade variability,” he said. “Some models point to the Pacific Decadal Oscillation as the cause. Other models point to other causes. It’s hard to know which is right and which is wrong.”
Hopefully, as the models become more sophisticated, they will coalesce around one answer, Brown said.
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There are three logical partitions of reality: scientific, philosophical, and faith. The scientific method was conceived to restrict runaway speculation into the latter two domains. Today, scientists routinely conflate not only the first and second, but also the third domains. The scientific domain is actually very limited in time and space. The accuracy of natural and enhanced perception is inversely proportionate to the product of time and space offsets from an established reference. The system is chaotic by virtue that is incompletely or insufficiently characterized and unwieldy. The scientific domain does not even include all of planet Earth, let alone all of the solar system, and certainly nothing beyond, where we have liberally indulged in inference justified by unscientific assumptions of independence (or weak correlation) and uniformity. The scientific method was designed to dissuade us from prediction and inference, and limit ourselves to forecasts and deduction, over an indefinitely short span of time and space. The scientific domain is characteristically utilitarian with a small overlap into the philosophical domain that guides development as we improve our skill and knowledge of the physical realm.
This is an analysis I like. One of the causes of science going bad is the general misconception of the importance and the applicability of science by the general public and probably also by many scientists. To do science the right way, you have to adhere to strict rules. These restrictions do limit what you can investigate, how you can investigate and if and how you can apply the results.
It may be that science brought about profound changes in our way of living, nevertheless the phenomena and processes suitable for scientific investigation are mainly limited to the physical realm, and even so within this realm you can only do good science by again limiting your scope. Many areas in life are beyond scientific investigation. Science can be a wonderful thing, as long as you have a healthy perspective on its limits.
Not really. Newton, Galileo, Francis Bacon, Lord Kelvin and ever so many scientists called themselves natural philosophers on the quite understandable grounds they were philosophers. As well as natural philosophy (what we call science), philosophy encompasses logic. The discipline that determines how mathematics works and computers. The world’s first science journal is called, oddly enough, Philosophical Transactions.
Consider the significance of hard partitions. As natural philosophy became rigorous and structured with the adoption of the scientific method, it, ironically, forced a natural partition of science and other philosophies. With the constrained frame of reference direct by the limited scope of the scientific method, improved knowledge and skill, science, for the first time, became utilitarian, not philosophical. Scientists use deduction to characterize and exploit phenomenon that are observable and reproducible. Still, we have philosophy (e.g. a-tom) to guide our investigation, and faith in knowledge and skill imperceptible to mortal senses (e.g. origin or pre-conception and post-mortem disposition).
Several scientists have assured me that deduction has no role to play in science since they claim deduction cannot generate new knowledge. That said, the philosophy of biology class I took had several graduate biology students who took to logic like ducks to water. Very handy to have them around as the lecturer was a physicist by training and needed some assistance to come up to speed with biology. The Git was a tad out of date also since his biology dated back to the late 60s. It was a great experience. The Git’s first lecturer in philosophy was also a physicist specialising in the study of causality.
The utilitarian use of philiosophers goes back a long way. Archimedes was renowned as a designer of war machines for example. You might wish there to be a hard demarcation line between philosophy and science, but many philosophers find it very blurry.
You speak of “the scientific method”. There isn’t a single method, just as there isn’t a single science. Jim Steele for example is a field biologist. It would be strange indeed if he used methods identical to Richard Feynman.
There is not the slightest bit of evidence that models can predict the future from first principles, except in the most trivial of cases.
The n-body problem crops up repeatedly in all branches of science, with different names. From quantum mechanics, to chaos theory, to stock market forecasting. The fundamental problem is this non-linear response whyen there is more than 1 attractor. For example.
Prior to 1 million years ago the ice ages had a cycle of 41 thousand years, as climate orbited the earths orbital obliquity attractor. Now for the past 1 million years the ice ages have a cycle of 100,000 years as climate orbits the earth’s orbital eccentricity attractor.
And none of this is linear. This wasn’t gradual change. The climate shifted from 1 state to the other, as it stopped orbiting the 41k attractor and started orbiting the 100k attractor. And it is beyond the power of current mathematics to solve the future state, beyond a matter of probabilities.
Like the weather. There is a X% chance ice ages will continue to have a 100k cycle, and a Y% chance they will shift back to a 41k cycle; and a 1-(X+Y)% chance something else will happen. But we don’t know when.
As always, I’m a member of the Fred Berple fan club, and would only add: We don’t know what X is, or Y is, and we cannot explain at all the gradual deepening of the orbital minima for each attractor…
Count me as a fan, too 🙂
“The northeast can expect up to three feet of dollars today…”
Each climate model is cr@p when held up to scrutiny. The ‘climate scientists’ think if they average all the cr@p models together, that they average themselves into something useful. That is the problem.
This is like mixing 1/2 gallon of the world’s best ice cream and 1/2 gallon of horse poop, and expecting 1 gallon of 50% ice cream.
… and the mixer is blind to which bucket is poop and which is ice cream before tasting the recipe output.
Hear hear Go Home.
Meanwhile, I am still stuck trying to figure out what the heck “average temperature” means. (Don’t even get me started on “average temperature” for a non-equilibrium system!)
Max Photon, its really quite simple. Done just like the CMIP5 model ensembles by brilliant IPCC climate scientists. Surely you trust them.
Add up N thingy anomalies. Why anomalies? Cause else you cannot add up thingies. Divide by N. That always gives the numerical anomaly thingy average to as many decimal places as you please. NASA GISS likes x.xx in thingies like 2014 warmest ever temperature PR, even though their accuracy is only x.x. See, easy peasy.
But if you want the resulting thingy anomaly average to actually mean something useful regionally, sorry you are out ot luck. Like CMIP5 models don’t downscale. Essay Last Cup of Coffee in ebook Blowing Smoke.
Which was perhaps your point, which perhaps I am sarcasticly reinforcing.
“Hopefully”! Hopefully, the fools keep throwing money at us (sarc).
If models rely, first and foremost, on gauging historic temperatures, they have not got a cat in hell’s chance.
Not when the entire record is mosherised!
Paul, you are up lateish for the UK.
For how badly, see my comments over at your place on your new ‘All of Paraguay has been diddled’ post. Well done! Booker has another column to write. Gavin more explaining to do. Not to mention the BEST ‘Mosherised’ buggyness you motivated Shub and I to discover over at JoNova’s yesterday that will drive Mosher battier than the BEST station 166900 discovery did over at Judith Curry’s. Explained high level over at your place in my last comment today. Regards
[Snip; D. Cotton. ~mod]
Well this group of Physicists with a population of one, says that Electromagnetic Radiation Energy is NOT “heat” (noun); and it can go in any direction it pleases.
But it is possible to subsequently convert some or all of that EM energy to waste “heat” whereupon it does then conform to the principles of thermodynamics.
While it is in the form of EM radiation, it does obey the conservation of etendue, ($3 French word for “throughput”) and indeed its redistribution IS bound by the second law of thermodynamics.
In fact famed thermodynamicist Rudolph Clausius was perhaps the first to derive “The Optical Sine Theorem” from the second law. That says basically that no optical system can for an image that is “brighter” than the source, nor can ANY optical system form an image that is “brighter” than an “Aplanatic” optical system can.
Brighter, in this case means higher radiance.
Also, if you drive your car from point (A) to some other point (B) carrying with you four gallons of “Radiator fluid”, does that qualify as “Convection” as far as “Heat” (noun) is concerned ??
[snip]
Well this physicist holds that since EM energy is NOT “heat”, and in fact it knows nothing of Temperature which is a thermal property of macro systems, that EM radiation does not, and cannot transfer “heat” anywhere. It transfers high quality energy which can in principle be 100% converted to “heat” at the receiving end; but “heat” (noun) does not make the journey. The converse is not true and “heat” cannot be 100% converted to any other form of energy.
Seems to have something to do with the fact that the kinetic motions of “hot” (adj) molecules are random in direction and it is not possible to marshal them all to move in the same direction.
But EM radiant energy can be converted into other things besides “heat”, such as electricity for example, which is another form of energy that is NOT heat, but can be converted into heat 100%, but again irreversibly. And some of that electricity can be converted (non thermally) into EM radiation, and at completely different frequencies from what form of radiant energy may have originally been converted to electricity.
But thermal radiant energy that is a consequence of the Temperature of a body (Planck radiation) can participate in bi-directional transport from one body to another regardless of their Temperatures; but as you point out the net flow of energy (as thermal EM radiation) is always from the hotter body to the colder body. The radiation making the journey (in either direction) still knows nothing whatsoever of Temperature.
Of course the radiant energy involved in the so-called “greenhouse effect” is a consequence of a single atom or molecule, not a large assemblage of molecules like thermal radiation. And that radiation also knows nothing of Temperature; but it knows a lot about atomic or molecular electron structure.
It’s time we stopped teaching new Physics students that “heat” (noun) is transported by conduction, convection, and radiation. Might just as well teach them that heat is transported by coal.
The means of producing heat is transportable and is transported by coal; and the means of producing heat is also transportable and is transported by EM radiation; but “heat” itself is not transported by coal or by EM radiation. Yes the lump of coal does have a Temperature, but don’t try keeping warm by just going to bed with a lump of coal under the sheets. It’s coal; it’s NOT “heat.” (noun).
[snip. Cotton again. ~ mod.]]
Doug Cotton alert!
I didn’t really want to pursue this issue further, but in the interest of even one person coming to understand it, it is worth another try.
Consider the Temperature range on earth (surface) on any ordinary northern summer day. When they say that the mean global Temperature is 288 K (+15 deg. C).
We know that at Vostok, which will be in the dead of winter night, the extreme of Temperature can get down to -94 deg. C (-137 F). And -100 F is fairly common.
At the other end, in the summer North African deserts in daylight, the in shade air Temp can be 136 deg. F about 57 deg C, and the hard surface rock or sand can get over +60 deg C and blacktop, maybe as much as 90 deg C.
So ignoring volcanic Temperatures, we can say that earth has an extreme Temperature range of about 150 deg. C. By that we mean simultaneously on the same day at the same time, and 110 deg C range is common as dirt.
So let’s say we make ourselves a laser tweezer machine which can hold a single atom or molecule stationary in a ultra high vacuum immune from collisions with anything else (well they can also hold living organisms for examination.)
So we are going to hold a single CO2 molecule in our field of view.
A plain common garden variety 16O-12C-16O CO2 molecule.
We will take it to Vostok, and the Sahara, and open the outside light shutters so as to allow light and LWIR photons to enter the chamber where our trapped CO2 is being watched by our microscope.
No matter where on earth we take it, or what the local Temperature is, we will find that sooner or later, our CO2 molecule will start doing the elbow bend dance, when a 15 micron or thereabouts LWIR photon wanders into the chamber, and excites that particular molecular resonance of the normally straight CO2 molecule. And the frequency of the oscillation will be pretty much the same wandering over the usual line width range.
So now we have a dilemma. The surrounding surface Temperature is between -90 and + 60 deg. C, and everywhere in between somewhere on earth, and yet we can still find 15 micron photons that excite the degenerate bending mode oscillation of the CO2 molecule. Evidently the wavelength of a photon is not dependent on the Temperature of the source.
Well actually we could take our gizmo into outer space where there is maybe a 2.7 K Temperature, or even close to the sun to get near that 6,000 K Temperature photon source. Well we’d have to stay a way off to not fry our machine.
We will find 15 micron photons in all of those places no matter what the Temperature is so long as it isn’t zero K.
So clearly the local Temperature is having no effect on the presence or behavior of 15 micron photons. They all have the same photon energy of about 130 meV and they exhibit no knowledge of the surface Temperature that gave rise to them (thermally).
Ah but you say; you have to look at the whole spectrum.
Well no, a photon has a unique frequency and energy = h(nu); it doesn’t have a spectrum (other than the line width).
But to humor you we will look at the spectrum anyhow.
So photons coming from the sun, exhibit a spectrum peaking at about 500 nm with 98% of its black body like energy between about 250 nm and 4.0 microns. That is 0.5 to 8.0 times the peak wavelength and is characteristic of a black body Temperature of 6,000 K which is almost right for the sun.
Ok, so now we have a broad spectrum of EM radiation with a peak at 500 nm, corresponding to a 6,000 K Temperature.
So being daring, we go out in our birthday suit and bathe in that 6,000 K spectrum of EM radiation.
Well I would expect to be instantly vaporized by that 6,000 K blow torch, but nothing of the sort happens.
Our broad spectrum of radiation doesn’t seem to know that it is supposed to have a Temperature of 6,000 K, corresponding to its spectrum.
Well sorry ! not one of those broad spectrum of energy photons has any notion that it is supposed to exhibit 6,000 K Temperature, corresponding to the spectrum of the whole gamut of photons arriving from the sun.
No photon knows anything about the Temperature of the surface or object that spawned it, and it can and will land on and get absorbed (maybe) by any surface, no matter what the temperature of that surface is.
G But remember this is just my opinion. If you use it in your PhD thesis, you might get expelled from school. But you will have learned something, even without your shingle.
As soon as I read ” Second Law of Thermodynamics” and “gravitational field” tossed into a comment I safely assume Doug Cotton is deploying yet another sock puppet.
[Thanx, deleted. ~ mod.]
These GCMs produce, at enormous cost, all sorts of different warming scenarios. Most of them are way up there in the really hot zone.
They disagree on slope, intensity and timing. But, taken together, are good enough for policy-making?
I think there’s a good chance they are all not even wrong.
Andrea see essays Models all the way Down, An Awkward Pause, Humidity is still Wet, and Cloudy Clouds in my ebook with the Judith Curry forward. You correctly paraphrase Dirac: so bas, not ever wrong.
Andres, and bad. Darned tablet touch screen.
the baby polar bear says to the mother polar bear.
” Mummy ? are you sure that I am a polar bear ? ”
” yes of course , don’t be silly you are a polar bear ”
” but are you really sure that I am a polar bear ? ”
” Look your mummy is a polar bear, your daddy is a polar bear ! Why do you keep asking if you are a polar bear ? ”
” because I am bloody freezing “
How to catch a polar bear:
First, take an ax and chop a hole in the ice
Next, get some peas & sprinkle them around the edge of the hole
(punchline—>) When the bear comes to take a pea, you kick him in the ice hole.
The IPCC spent years saying that natural variability (not including volcanoes) was just a tiny +/-0.1C.
So the warming observed to date could only be from GHGs.
From the IPCC AR4 2007 Report.
http://www.edf.org/sites/default/files/climate/ipcc-global-and-continental-temperature-change_0.jpg
Bill, the bigger message in the bottom three panels is that there is no distinquishable anthropogenic signal prior to circa 1950. The whole IPCC anthropogenic case falls apart immediately, since as Lindzen first pointed out, take 1920 to 1945 and 1975 to 2000. Set them side by side without the anomaly number. They are indistinguishable. See essay cAGw for the exact juxtapositions including the bottom three panels.
Graphical proofs are always fun. Juries of laypersons get them immediately. Regards.
Right… because ALL of the temperature charts I’ve look at start at 0,0 and end and 1,1.
(/sarc)
Straight lines would be boring.
High winds blowing the pine trees, the limbs flop, that makes the tree rings wiggle thus the wiggle in the graphs. Just ask the PHD’s.
But, but …haven’t we been told many times that THE SCIENCE IS SETTLED? CO2 is causing catastrophic global warming/climate change. We can’t predict 2016 or 2020 but we are absolutely sure that 2100 will be HOT and BAD.
The dog ate the climate models. More back-pedaling and excuses.
http://news.yahoo.com/severe-la-nina-weather-events-pacific-may-double-161250881.html
sorry to thread bomb. ..Its just to outrageous.
michael
I can’t argue with that 😉
The warmest CSIRO in Australia are proudly trumpeting today that Global Temperatures will rise by 5 degrees C by the end of the century. When will the insanity stop ?
I wouldn’t worry too much, Bunyip. According to Paul Brown, author of iGlobal Warming Blandford (1996)
So temperatures have already risen by 323–326°F since the nineteenth century. Did you notice? Neither did I…
did not have to wait long!
http://www.huffingtonpost.com/2015/01/26/climate-change-northeast-snow_n_6549996.html
A study of climate models is pointless for the simple reason that one of their assumptions is that increasing CO2 concentration causes an increase in temperature which is clearly discredited by empirical data. There are 368 locations listed on the World Data Centre for Greenhouse Gases and most locations contain multiple data files. I have yet to find a file of historic CO2 concentration data that shows a statistically significant correlation between monthly increments in CO2 concentration versus temperature increments be they ground station or satellite measurements. The correlation is usually a small positive or negative number with very high probability that the value is zero.
While the IPCC obviously does not investigate such data, preferring instead to play computer games, there is value to be gained by study the data. My work to date has shown the following correlations between the annual increment in the CO2 concentration and the average of the relevant satellite temperature over each 13 month period. Provisional results for the correlation coefficient are :
Mauna Loa 0.69
NOAA Pacific Ocean(00N) 0.62
Cape Grim vs satellite temperatures 0.64
Macquarie Island 0.73
Izana – Tenerife 0.54
Barrow 0.36
South Pole 0.22
Cape Kumukahi 0.67
In all cases the probability of zero correlation is insignificant.
My conclusion to date is that the global temperature has controlled the rate of change of atmospheric CO2 concentration with the temperature increase being the natural consequence of the last ice age and mini-ice ages. The source of the CO2 may be effervescence from the oceans or biogenic CO2 due to the proliferation of life forms as temperature increases. This is reflected in the coefficients being less in the polar regions where there is less biological activity.
[Snip.]
I given up!
[Snip. PNG. Cotton again. ~ mod.]
It’s understandable that Anthony deletes comments…
[SNIP. Very understandable, after seeing your scurrilous comments about him on your own blog. But in this case a moderator deleted your comments, not Anthony. You are persona non grata here. Why can’t you get the message? ~mod.]
[…and, since Doug Cotton can’t seem to get it into his head that his bizarre off-topic comments are not welcome here (or at almost every other climate blog), no matter what sock puppet persona he tries, his comments WILL BE summarily deleted. Even PSI/Slayers have rejected you, get a clue.] – Anthony
[PNG D. Cotton. ~mod.]
And yet the global warming climate change climate disruption machine rolls on in the media and blogs, Kind of like Jason in the Halloween movies, no matter how many times you kill him, he comes back to life to murder more innocents.
Maybe it is inertia, once the boulder starts down the mountain it is difficult to stop. Eventually at the bottom the boulder will stop, the question is how much damage it will cause on the way down.
Michael Myers is the Halloween monster. Jason is from Friday the 13th.