From his blog http://www.drroyspencer.com/ which I’m repeating here to help get wide exposure.
A Challenge to the Climate Research Community
I’ve been picking up a lot of chatter in the last few days about the ’settled science’ of global warming. What most people don’t realize is that the vast majority of published research on the topic simply assumes that warming is manmade. It in no way “proves” it.
If the science really is that settled, then this challenge should be easy:
Show me one peer-reviewed paper that has ruled out natural, internal climate cycles as the cause of most of the recent warming in the thermometer record.
Studies that have suggested that an increase in the total output of the sun cannot be blamed, do not count…the sun is an external driver. I’m talking about natural, internal variability.
The fact is that the ‘null hypothesis’ of global warming has never been rejected: That natural climate variability can explain everything we see in the climate system.
@PETER DENIS ROBERTS February 3, 2011 at 8:41 am:
Exactly. The models have never succeeded in replicating recent climate history, telling us that for 1) no, we don’t, for 2) it is not just data but getting the formulas correct and translated into code correctly – including constants, and for 3) I think that is one of the major reasons WUWT even exists, to point out that the model’s predictions are hooey.
If models predict correctly over a reasonable period of time, it would be because the underlying assumptions, data and constants are correct. Those models need to be differentiated from the prototype models such as are ubiquitous in climate science.
I posit the obvious: That the models aren’t predicting correctly because the underlying science is poorly understood, the data is improperly processed and the constants – the “fudge factors” such as used for clouds – are arrived at inductively instead of deductively (meaning they adjust the constants until the output “looks good” and then assume that means the constant has veracity.
Feet2theFire says:
February 3, 2011 at 5:41 pm
Nice work, Sir. I hope you visit often. Our PNS vanguard would benefit enormously. Well, they could benefit.
David Falkner says:
February 3, 2011 at 5:03 pm
It’s all a bit circular, don’t you think?
Indeed, which is why the ‘challenge’ is no good.
KR says: February 3, 2011 at 8:09 am
“Looking at them, the Limsakula paper discusses ENSO influences … I don’t see anything in that paper regarding long term cycles causing the late 20th century warming trend, though.”
The only “late 20th century warming trend” I see was related to the El Nino Southern Oscillation (ENSO):
http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_Jan_2011.gif
If we remove the 98 El Nino there is no “late 20th century warming trend”. And if we remove last year’s El Nino, all I see is a .2 degree increase between 2001 and 2007. Which non-ENSO related “late 20th century warming trend” are you referring to?
Leif Svalgaard says:
February 3, 2011 at 8:31 pm
Indeed, which is why the ‘challenge’ is no good.
The dataset has naturally (to the dataset) occurring boundaries of variance. It has been claimed by those who model the dataset that you cannot produce the data without CO2 forcings, which means that the naturally occurring variations have been eliminated as a cause (says they). Dr. Spencer is asking when this happened.
What causes the data to vary is important for the purpose of this question, but neither side can lay claim to it. That is why the null hypothesis should be that the dataset is varying within its normal boundaries. Since the null hypothesis always contains the equation of equality, the null should reflect a state of no change in this scenario. μ=0 as it were.
KR says: February 3, 2011 at 8:09 am
“Looking at them, the Limsakula paper discusses ENSO influences … I don’t see anything in that paper regarding long term cycles causing the late 20th century warming trend, though.”
Empirical evidence for interannual and longer period variability in Thailand surface air temperatures – Atsamon Limsakul and Joaquim I. Goes
” In addition, the overall warming trends of Tmax, and Tmin in the 1980s and 1990s were consistent with the tendency for more frequent El Niño events and fewer La Niña events since the late 1970s.”
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V95-4PBDPT6-1&_user=10&_coverDate=02%2F29%2F2008&_rdoc=1&_fmt=high&_orig=browse&_origin=browse&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=e197d12b2e643d922e656e7dc35c6eda
“Long term cycles”? For ENSO we have basic index and episode data back to 1950;
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml
Pacific Ocean Equatorial Heat Content back to 1979;
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt
and “Argo deployments began in 2000 and by November 2007 the array is 100% complete. “:
http://www.argo.ucsd.edu/
The longest ENSO cycle we can measure at present is 60 years. Should Limsakul and Goes write on the 90 year cycle that may or may not exist, but we won’t know until we have sufficient historical records to be able to measure it?
Also, Earth’s Thermohaline Circulation;
http://en.wikipedia.org/wiki/Thermohaline_circulation
is caused when “wind-driven surface currents (such as the Gulf Stream) head polewards from the equatorial Atlantic Ocean, cooling all the while and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of around 1600 years) upwell in the North Pacific (Primeau, 2005).”
We have 60 years worth of basic and 4 years of reasonable quality ocean temperature data on a cycle “with a transit time of around 1600 years”. At present, our capacity to predict changes in the Thermohaline Circulation is essentially nil.
As I pointed out earlier, “One of the “pumps” that helps drive the ocean’s global circulation suddenly switched on again last winter for the first time this decade. The finding surprised scientists who had been wondering if global warming was inhibiting the pump and did not foresee any indications that it would turn back on.
The “pump” in question is in the western North Atlantic Ocean, where pools of cold, dense water form in winter and sink beneath less-dense warmer waters. The sinking water feeds into the lower limb of a global system of currents often described as the Great Ocean Conveyor. To replace the down-flowing water, warm surface waters from the tropics are pulled northward along the Conveyor’s upper limb.”
http://www.whoi.edu/page.do?pid=12455&tid=282&cid=54347
http://www.nature.com/ngeo/journal/v2/n1/abs/ngeo382.html
Based on our limited understanding of Earth’s climate system, any predictions about Earth’s climate system and the long term trajectory of its average temperature are, at best, educated guesses. We are still learning how to accurately measure Earth’s temperature, much less accurately predict it 50 – 100 years into the future. Those who claim to be able to accurately predict the long term trajectory and likely future state of Earth’s average temperature, are either deluding themselves, or lying.
Leif Svalgaard says:
You mention that several natural cycles exists. Some would say that they don’t exist [hockey stick people] or are actually man-made [aerosols, CO2, land use, etc], so we are back to square one on that.
Natural cycles have been known to man for millennia before the hockey team started abusing statistic methods. Take the claim that there’s anything “unnatural” about the current Arctic warming: Not only does the thermometer record of the first half of the 20th century prove this claim wrong, Greenland provides evidence in the form of norse settlements. Going further back in time, the current tundra of Hardangervidda in Norway contains 6000 year old trees buried in marshes.
Hockey stick people and their artifacts of severe statistical abuse are no more credible than ufologists or astrologists.
Theo Goodwin said “Both memes are truly desperate and despicable.”
Could some one clue me in as[] to what a memes is?
The problem with Dr Spencer’s challenge is that the null hypothesis, that natural climate variation is responsible for the observed warming, is inherently unfalsifiable, even if it is false. I pointed this out on Dr Spencer’s blog, and challenged him to give an example of an experiment or observation that would potentially falsify that hypothesis. No answer has been forthcoming and my posts now seem to be in some from of moderation limbo, perhaps never to see the light of day. Make of that what you will.
Karl Popper says that a scientific theory should prohibit things, the more it prohibits, the better the theory. The reason for this is that it is fundamentally impossible to prove any proposition regarding the real world, they can only be falsified. A theory that makes prohibitions is a theory that is falsifiable, it can be proven wrong. Unfalsifiable hypotheses are unscientific, if everything that could possibly ocurr is consistent with the theory then it explains everything and yet nothing. It is not unduly surprising that an unfalsifiable theory has not been falsified, or that nobody has attempted to do so.
The challenge also involves several straw men, such as the idea that “The science is settled”. Gavin Schmidt and Phil Jones have gone on record as explicitly saying this is not the case, see here: http://www.realclimate.org/index.php/archives/2009/12/unsettled-science/ and here: http://news.bbc.co.uk/1/hi/8511670.stm (question N)
Dikran Marsupial:
At February 4, 2011 at 9:12 am you assert:
“The problem with Dr Spencer’s challenge is that the null hypothesis, that natural climate variation is responsible for the observed warming, is inherently unfalsifiable, even if it is false. I pointed this out on Dr Spencer’s blog, and challenged him to give an example of an experiment or observation that would potentially falsify that hypothesis.”
The null hypothesis is NOT unfalsifiable. It would be disproved if AGW – or anything else – were seen to have induced a change to climate not observed (in the geological record) to have happened previously in the holocene.
And if the null hypothesis is not disproved then there is no reason to suppose that AGW – or anything else – is significantly changing climate.
That is NOT a “problem” to anybody except true believers in the – AGW-hypothesis.
Richard
Richard Courtney, You cannot falsify the null hypothesis by showing that AGW is responsible for some of the warming as that would require a circular reasonong; you yourself said (words to the effect) that there is no reason to suppose the warming is due to AGW if you have not disproved the null hypothesis!
If you want to show the natural variability hypothesis is falsifiable, it is straightforward. Specify an experimental result or observation that would not be consistent with natural variability being the cause of the rise. It appears Dr Spencer could not, can you?
By the way, David Hume said that you should apportion your belief to the evidence. That is exactly what scientists still do today. Neither hypothesis has been falsified, so both are plausible; the reason that mainstream scientists apportion more of their belief [in the sense of a Bayesian probability rather than religious faith before anyone gets in the obvious one-liner] to AGW is that there is more evidence to support it than there is the hypothesis that it is due to “natural variation” (for which no mechansim has been specified and which apparently makes no quantitative predictions that could be proven wrong and hence allow the falsification of the theory).
An Inquirer References on increasing specific (absolute) humidity can be found at:
Dai 2006, Recent Climatology, Variability, and Trends in Global Surface Humidity, J. Climate, 19, 3589-3606, Willett et al. 2008, Recent changes in surface humidity: development of the HadCRUH dataset, J. Clim..21, 5364:5383, Berry & Kent, 2009, A New Air-Sea Interaction Gridded Dataset from ICOADS with Uncertainty Estimates, Bulletin of the American Meteorological Society, 90(5), 645-656 (DOI: 10.1175/2008BAMS2639.1). The last is ocean only, but since that’s the majority of the Earths surface it’s relevant.
These are discussed at Tamino’s blog (http://tamino.wordpress.com/2010/08/08/urban-wet-island/) where he shows the agreement between these data sets and rather astounding consistency with GISS temperatures.
With regards to natural cycles (such as ENSO), Tamino has a post (http://tamino.wordpress.com/2011/01/06/sharper-focus/) regarding what the trends look like when accounting for ENSO cycles, volcanic forcings, etc.
Note that a serious issue with “natural cycles” causing recent heating is that atmospheric outgoing long wave radiation has decreased since 1970. If an ENSO or other oceanic cycle was redistributing heat in a temporary cycle, we would expect OLR to increase as the world warmed, not decrease.
The only way we can see warming with decreasing OLR is if less OLR is getting out of the atmosphere – an atmospheric effect. Clouds? Clouds respond quickly to temperature and humidity. Aerosols are fairly well understood (not perfectly), but mostly seem to have a cooling effect.
And any claims that natural cycles are causing recent heating need to explain why measured CO2 increases are not causing it, in defiance of all known physics. Two arguments, not one.
Dikran Marsupial,
You don’t understand the concept of the null hypothesis, which is the statistical hypothesis that states that there are no differences between observed and expected data. Try to follow what this means.
It means that any alternative hypothesis must be tested against the long-held null hypothesis of natural climate variability within the parameters of the Holocene climate. The alternative CO2=CAGW hypothesis expects catastrophic AGW from an increase in CO2. That has not happened, and every attempt to show a global effect has been debunked in turn: sea level rise, glacier retreat, ocean acidification, sea ice, ocean pH, coral bleaching, migration, species extinction, etc. The claim that CO2 is the cause has been debunked in every instance; no exceptions.
If an alternative hypothesis, such as CO2=CAGW, when compared with the past climate cannot show any measurable difference from past episodes of temperature trends, global temperatures or other climate variables, then the alternative hypothesis fails. Only if the alternative hypothesis shows that there are measurable differences between observed and expected data would the alternatie hypothesis show that CO2 has made a quantifiable difference.
But we find that, in fact, there are no differences between the climate during the Holocene and the current climate. What is happening now has happened repeatedly in the past. It is the same now as then. In fact, the current climate is especially benign compared with the extremes of the Holocene – when CO2 was quite low.
The verifiable fact that there is no identifiable global harm attributable to CO2, and the fact that computer climate models have an abysmal prediction record, and the fact that one by one, all alarmist predictions of global doom have failed to materialize, supports the null hypothesis – which has never been falsified.
The *very mild* natural warming cycle of 0.7°C over the past century is not only nothing unusual, it has been beneficial to the biosphere. Temperatures have risen as much as 27°F in only a decade prior to the industrial revolution, and have fallen almost as fast – at a time when CO2 was very low. The current climate is excellent, and shows no signs of runaway global warming or other planetary climate catastrophes. Thus, the alternative hypothesis has been tested against the null hypothesis, and it has failed.
When you understand the function of the null hypothesis, you will see why it is such a powerful concept. It allows us to separate wild-eyed hand waving over an evidence-free belief in climate catastrophe from entirely normal and natural climate fluctuations, which have been repeated over the past ten millennia, and which continue unchanged in either duration or extent.
Nothing unusual is happening, and the addition of harmless and beneficial CO2 has been a net benefit with no downside, as there is zero verifiable evidence of global harm due to the rise in that minor trace gas, and with substantially increased agricultural production resulting from the addition of beneficial carbon dioxide.
One last thing, then I’ll likely need to hide in a cave for a while and get some work done…
From all the paleoclimate research, records of solar activity, knowledge of orbital precessions, etc., CO2 in the past amplified the glacial cycles – we wouldn’t have had such temperature swings in the past without some amplification, as the forcing changes from sunlight were actually pretty small in the glacial cycles. That’s where a lot (not all, though) of our “climate sensitivity” numbers come from – glacial cycles establishing a minimum value on long term sensitivity to forcings.
We’ve got really good records of forcing over the last couple of hundred years; the last half million including ice cores – solar inputs, aerosols, CO2 levels, orbital dynamics, etc. Nothing over that period reaches the rate of change we’re seeing now, by an order of magnitude.
The forcing (imbalance between incoming and outgoing radiation) from our current CO2 levels is a level that has not been seen in the last half million years – it hasn’t exceeded 295, and here we are at 395ppm and rising. Everything we know about physics indicates that it’s going to warm up! We seem headed for a 2C temperature rise by 2100; the last time temps were 2C higher globally we had essentially no ice caps and 6 meters higher oceans. I don’t expect that for centuries (takes a while to melt ice caps), but it’s something to think about.
If you think it’s a natural cycle, rather than the (well understood) CO2 forcing, then find the cycle and identify it! If you cannot identify a cycle, then you might as well be claiming that the temperature increases are due to leprechauns, invisible pink unicorns, or (as I suggested earlier) the lawn gnome Illuminati. It’s handwaving, not science, if you can’t look at it and poke it with a stick. Undefined “natural cycles” is a cop-out.
KR said; “If you think it’s a natural cycle, rather than the (well understood) CO2 forcing, then find the cycle and identify it! If you cannot identify a cycle, then you might as well be claiming . . . . .”
Hey, “HUCK” long time no see . . . . paint your own fence . . . . If you don’t think there is a cycle, so be it . . . . Just quite playin’ that old BS confidence game . . . .
People, get paid good money to find out stuff . . . make your own projections based on what you think the cause is . . . and may you live long and prosper. . .
Have a nice life!!!!!
Leif Svalgaard says:
February 3, 2011 at 11:02 am
don penman says:
February 3, 2011 at 9:09 am
About ‘existence’:
There is a circular argument here. The ‘natural cycles’ are deduced from the data, so it is circular to discuss whether the cycles explain or do not explain the data.
The natural cycles are patterns produced by some from the data,they either exist or don’t exist according to the data.I would have thought that if the null hypothesis that all temperature change happening is natural is disproved it would be manifestly obvious, there would be no disagreement if we were experiencing heatwaves every year max temps constantly going up (it would be like having inflation in our temp records) every decade world temps would be going up half a degree or so .
KR says Note that a serious issue with “natural cycles” causing recent heating is that atmospheric outgoing long wave readiation has decreased since 1970. If an ENSO or other oceanic cycle was redistributing heat in a temporary cycle, we would expect OLR to increase as the world warmed, not decrease.
So, the world has been cooling since 1970.
The world has been cooling since the beginning of the global warming of the Holocene. What you think of as warming is only the ever decreasing high spurts into warmth and low dips into cold in the general hiccupy slide down back into cold. I think you’re failing to appreciate that we are actually in an ICE AGE. When we actually reach that tipping point back into a mile or two of ice over the countries affected by this is debatable, could be tomorrow.
And any claims that natural cycles are causing recent heating need to explain why measured CO2 increases are not causing it, in defiance of all known physics.
The natural cycles for hundreds of thousands of years have shown that CO2 had nothing to do with immense global climate changes. You have to prove a) these have stopped, b) that CO2 by itself is causing these now.
So, please, let’s have this “all known physics”. We’re still waiting for an explanation of CO2 causing global runaway warming in AGW. Explain it. Give us the science. Take us through it step by step. Provide the evidence.
KR says:
“If you think it’s a natural cycle, rather than the (well understood) CO2 forcing… & blah, blah, etc.”
KR, like all alarmists you have the scientific method exactly backward. It is the purveyors of the CO2=CAGW conjecture who have the burden of showing causation. Since they have failed, like Trenberth they try to turn the sccientific method upside down, and put the burden on scientific skeptics. That is a cop out.
In the scientific method one posits assumptions, uses mathematics and logic to predictive/descriptive conclusions, and checks results against reality [empirical evidence]. If the reality says no, then the assumptions are changed and the process is repeated.
The problem with the CAGW crowd is that they do not follow the scientific method. Reality invalidates their assumptions, but they do not change them, thus turning them into beliefs.
The onus is not on skeptics to either disprove or explain natural climate cycles, which have occurred since the planet first had an atmosphere: ei incumbit probatio, qui dicit, non qui negat; cum per rerum naturam factum negantis probatio nulla sit: “the proof lies upon him who affirms, not upon him who denies; since, by the nature of things, he who denies a fact cannot produce any proof.”
As to the hypothesis that C02 produced by human combustion of fossil fuels is causing “unprecedented” global warming that will lead to climate catastrophe: the onus lies on those who say so.
As to the proposition that there has been an alarming late 20th century spike in global temperatures that goes beyond past natural variability: the onus lies on those who say so.
Blaming skeptical realists for your inability to show any global harm as a result of the increase in a minor trace gas brings about the pseudo-scientific demand that skeptics must essentially prove a negative. It is all based on the argumentum ad ignorantium: “Since we cannot explain natural variability, then CO2 must be the primary cause.” Ridiculous.
No wonder alarmists get their heads handed to them in debates. They pervert the scientific method, and self-reinforce their anti-science in their echo chamber blogs like realclimate. But here on WUWT, which doesn’t censor contrary viewpoints, the truth comes out.
Of course it will make no difference with you; your mind is made up and shut tight. But the majority in the undecided camp read these comments and make up their own minds. That’s why the tide is turning. And there is nothing you can do about it.☺
KR says: February 4, 2011 at 12:15 pm
“With regards to natural cycles (such as ENSO), Tamino has a post (http://tamino.wordpress.com/2011/01/06/sharper-focus/) regarding what the trends look like when accounting for ENSO cycles, volcanic forcings, etc.”
I tried to have a logical discussion with Tamino, but he was threatened by the facts and had to censor my comments. If Tamino’s writing can’t withstand reasoned criticism, then it’s not worth reading…
“Note that a serious issue with “natural cycles” causing recent heating is that atmospheric outgoing long wave radiation has decreased since 1970. If an ENSO or other oceanic cycle was redistributing heat in a temporary cycle, we would expect OLR to increase as the world warmed, not decrease.”
This is gibberish, I see nothing of value. Show us links to support your unintelligible assertions.
“And any claims that natural cycles are causing recent heating need to explain why measured CO2 increases are not causing it, in defiance of all known physics.”
I am amused by your statement. I’ve presented multiple citations above that support the possibility that natural cycles are the predominate force behind climate change. So far no one has been able to refute, dispute or discount any of them. Your bluster does not change this fact…
GAAAAH! Spent 45 minutes on a reply, and it appears to have not registered…
Trying again. If this doesn’t work, I’m going for a stiff drink…
—
Myrrh – “Take us through it step by step. Provide the evidence.” You don’t ask for much, do you? Wikipedia should provide pretty much everything I could contribute.
GHG’s (tri-atomic and above molecules with appropriate dipoles, such as CO2, H2O, methane, ozone) absorb and emit IR based on temperature.
Half the energy emitted by GHG’s goes downward (backradiation, well measured since mid-1950’s). That means less surface radiation goes to space, and the surface is ~33C warmer than it would be without GHG’s (ignoring albedo changes such as global ice sheets, as it’s sufficient to show that conditions would be different without GHG’s).
Less surface radiation to space means lower emissivity of the planet. Energy out to space is a function of effective emissivity and temperature (http://en.wikipedia.org/wiki/Thermal_radiation, Stefan-Boltzmann relationship, _very_ well established).
If incoming visible light energy is > outgoing IR, energy will accumulate in the climate. Satellite data since the 1970s (Hansen 2005, http://meteora.ucsd.edu/cap/pdffiles/Hansen-04-29-05.pdf, and others) indicates that IR has been decreasing. That’s an imbalance.
Given general conservation of energy, we’re going to see increasing temps until overall IR matches incoming solar energy. That means it’s going to get warmer, which all data (conspiracy theories http://www.youtube.com/watch?v=e_mPrhwpZ-8 aside) indicate is happening.
So – everything we know about spectroscopy, molecular dynamics, and emissions – versus undefined natural cycles. Hmmm…
—
Smokey – We’ve got lots of data and observations about CO2 effects. The burden of evidence (http://en.wikipedia.org/wiki/Philosophic_burden_of_proof) is on you to disprove the last 150 years of science, not the people working from accepted evidence.
CO2 levels are higher than they have been in half a million years.
CO2 rising at 100ppm over 120 years? In all historic contexts that’s taken 5,000-20,000 years.
Temp changes are an order of magnitude larger than anything we’ve seen in the historic record aside from (possibly) the PETM shifts – and I really hope we’re not seeing a massive clathrate explosion.
Finally – if you assert an undefined natural cycle, as opposed to everything we know about CO2 and radiative physics, the burden is on you to prove (1) that the natural cycle is causing warming, and (2) the well understood CO2 increases are not. Go for it…
Ack!!! Another 45 minutes wasted. Watts, your web-site sucks.
If there are limits on content, size, length, phase of the moon, on your postings, PLEASE DESCRIBE THEM AND INCORPORATE SUCH LIMITS INTO YOUR EDITOR!!!
REPLY: Then don’t visit
I give up. I’ve spent an hour and a half attempting to answer comments directed to me, and my posts have not registered.
Myrrh, look at http://en.wikipedia.org/wiki/Greenhouse_effect. I think that covers your“evidence”. Five minutes with Google should answer all the questions you’ve posed.
Smokey – the burden of proof is on those who deny CO2 spectroscopy, measurements of temperature increase, and who claim conspiracies among thousands of independent researchers (http://www.youtube.com/watch?v=iJPFSNu_QNs). Not on everyone working from the evidence.
This web site is painful to use. I have better things to do with my time – such as a decent beer that is calling me.
Watts – A very serious question for you, if it’s possible to get an answer. I’ve tried to post a couple of extended answers to really reasonable questions, only to have my postings vanish into the Ethernet. I hate leaving a reasonable question (or even some I consider unreasonable) unanswered.
Are there length limits to postings here? I will gladly comply if I know what they are!
REPLY: My goodness you are brusque. First you tell me my website “sucks” then you demand answers by addressing me by my last name in bold. Perhaps asking nicely might be a better tactic? So far you aren’t making any friends. I rescued one of your posts from the spam filter, see it above. There’s no limit on length, but the spam filter run by wordpress.com interprets comments with many links as spam, and holds them for moderators to inspect, and it will wholesale delete any comments that might have embedded code (from say cut and paste from other websites) that is outside basic HTML as a protection measure.
So before you start blaming me or my website, please consider other options first. – Anthony