Do you agree that from 1995 to the present there has been no statistically-significant global warming
Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significance level. Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods.
MIT Professor Richard Lindzen said something similar in a WUWT guest post:
There has been no warming since 1997 and no
statistically significant warming since 1995.
And, climatologist Pat Michaels said recently in an essay at The GWPF:
“The last ten years of the BEST data indeed show no statistically significant warming trend, no matter how you slice and dice them”. He adds: “Both records are in reasonable agreement about the length of time without a significant warming trend. In the CRU record it is 15.0 years. In the University of Alabama MSU it is 13.9, and in the Remote Sensing Systems version of the MSU it is 15.6 years. “
So with Dr. Ben Santer now solidly defining 17 years as the minimum to determine a climate signal, what happens to the argument when we reach 2013-2014 and there’s still no statistically significant upwards trend?
Separating signal and noise in climate warming
LIVERMORE, Calif. — In order to separate human-caused global warming from the “noise” of purely natural climate fluctuations, temperature records must be at least 17 years long, according to climate scientists.
To address criticism of the reliability of thermometer records of surface warming, Lawrence Livermore National Laboratory scientists analyzed satellite measurements of the temperature of the lower troposphere (the region of the atmosphere from the surface to roughly five miles above) and saw a clear signal of human-induced warming of the planet.
Satellite measurements of atmospheric temperature are made with microwave radiometers, and are completely independent of surface thermometer measurements. The satellite data indicate that the lower troposphere has warmed by roughly 0.9 degrees Fahrenheit since the beginning of satellite temperature records in 1979. This increase is entirely consistent with the warming of Earth’s surface estimated from thermometer records.
Recently, a number of global warming critics have focused attention on the behavior of Earth’s temperature since 1998. They have argued that there has been little or no warming over the last 10 to 12 years, and that computer models of the climate system are not capable of simulating such short “hiatus periods” when models are run with human-caused changes in greenhouse gases.
“Looking at a single, noisy 10-year period is cherry picking, and does not provide reliable information about the presence or absence of human effects on climate,” said Benjamin Santer, a climate scientist and lead author on an article in the Nov. 17 online edition of the Journal of Geophysical Research (Atmospheres).
Many scientific studies have identified a human “fingerprint” in observations of surface and lower tropospheric temperature changes. These detection and attribution studies look at long, multi-decade observational temperature records. Shorter periods generally have small signal to noise ratios, making it difficult to identify an anthropogenic signal with high statistical confidence, Santer said.
“In fingerprinting, we analyze longer, multi-decadal temperature records, and we beat down the large year-to-year temperature variability caused by purely natural phenomena (like El Niños and La Niñas). This makes it easier to identify a slowly-emerging signal arising from gradual, human-caused changes in atmospheric levels of greenhouse gases,” Santer said.
The LLNL-led research shows that climate models can and do simulate short, 10- to 12-year “hiatus periods” with minimal warming, even when the models are run with historical increases in greenhouse gases and sulfate aerosol particles. They find that tropospheric temperature records must be at least 17 years long to discriminate between internal climate noise and the signal of human-caused changes in the chemical composition of the atmosphere.
“One individual short-term trend doesn’t tell you much about long-term climate change,” Santer said. “A single decade of observational temperature data is inadequate for identifying a slowly evolving human-caused warming signal. In both the satellite observations and in computer models, short, 10-year tropospheric temperature trends are strongly influenced by the large noise of year-to-year climate variability.”
The research team is made up of Santer and Livermore colleagues Charles Doutriaux, Peter Caldwell, Peter Gleckler, Detelina Ivanova, and Karl Taylor, and includes collaborators from Remote Sensing Systems, the National Center for Atmospheric Research, the University of Colorado, the Canadian Centre for Climate Modeling and Analysis, the National Oceanic and Atmospheric Administration, the U.K. Meteorology Office Hadley Centre, and Lawrence Berkeley National Laboratory.
###
Source: http://www.llnl.gov/news/newsreleases/2011/Nov/NR-11-11-03.html
Anne M Stark, LLNL, (925) 422-9799, stark8@llnl.gov
1, 2 and 3, all move the goal posts…
What will happen is the new minimum for determining a human influence on climate will be 20 years.
[snip. Read the site Policy. ~dbs, mod.]
I wanna beat the crap out of that man.
BTW, whats exactly that human fingerprint? Failed hotspot?
One way to win is to define the rules. Then redefine them as needed.
That sounds unfair but it may work, which is why it is sometimes done. So if Santer says 17 now he may say 18 or 19 soon. Or he may not.
We know that at some point rule changes won’t work. But a couple of more years – whether warmer or colder – won’t change many minds.
My experience in metrology, acquired in my career as an Analytical Chemist, is that although there are extremely sophisticated techniques for sorting out a weak signal from strong noise, they involve mathematics – and mathematical assumptions about the nature of the signal and the nature of the noise – that is far beyond the ken of most ‘climatologists.’
The mathematics can involve Fourier Transforms and / or Principle Component Analysis. The assumptions involve assigning characteristics to the signal and the noise, based on *known* mathematical properties of both – characteristics which cannot be justifiably applied in the case of climate.
Other than that, your only resort is to acquire *massive* amounts of data so that the statistical variances in all trends are reduced sufficiently to discriminate between periodic and secular trends.
Until the data has been collected, the problem is very like that of determining “mean sea level” from instantaneous wave height measurments – during a storm.
“what happens to the argument when we reach 2013-2014 and there’s still no statistically significant upwards trend?”
IPCC AR6 (2022);
” . . . climate models can and do simulate short-ish, 15- to 17-year “hiatus periods” with minimal warming, even when the models are run with historical increases in greenhouse gases and sulfate aerosol particles. They find that tropospheric temperature records must be at least 25 years long to discriminate between internal climate noise and the signal of human-caused changes”
So with Dr. Ben Santer now solidly defining 17 years as the minimum to determine a climate signal, what happens to the argument when we reach 2013-2014 and there’s still no statistically significant upwards trend?
Then Dr Santer will redefine the period to 19 years, or 23, or whatever prime number takes his fancy at the time…
Why 17 years? Is it because it’s a prime number? . If so we’ve already had 13 years of no warming, but I guess that was the wrong prime number.
Hansen was happy to announce global warming after 10 years of warming.
“To address criticism of the reliability of thermometer records of surface warming, Lawrence Livermore National Laboratory scientists analyzed satellite measurements of the temperature of the lower troposphere (the region of the atmosphere from the surface to roughly five miles above) and saw a clear signal of human-induced warming of the planet.”
Wow-wee! Those satellites are sure sophisticated, being able to tell the difference between human-induced warming and just plain warming.
“The positive trend is quite close to the significance level. ”
Fuzzy isn’t part of mathematics.
Somebody should tell these thermodynamically-challenged profs
that their precious forcing is laughably small,
as per the Wikipedia graph so well known here at WUWT:
http://upload.wikimedia.org/wikipedia/commons/9/9c/ModtranRadiativeForcingDoubleCO2.png
It’s easy to calculate that a climatologically undetectable 0.7 deg K
will lift the 600ppm curve up so it has the same integral as the 300ppm curve.
Doesn’t ‘forcing’ seem too muscular a word for such a tiny effect?
Given that the graph is for 50% humidity and no clouds,
the real effect of CO2 should better be called a ‘SUGGESTION’.
Cloud changes… now that’s a forcing,
as shown by the breezes that spring up at the edge of cloud-shadows.
Why should this undetectable temperature rise get catastrophically amplified
when far larger natural fluctuations do not? Truly, CO2 is a magic molecule.
It looks more like there never will be much of a ‘greenhouse signal’,
just as the WWII planes never came for the pathetic Cargo Cultists.
Only this time the Cultists are forcing us to build giant bird-slicers
that cost us far more steel, concrete, rare-earths, and worker deaths
per actual power output than those Eeeville nuclear reactors.
As for any of those stupid obscenities running for 40 years…
What a load of crap. We’ve had thirty plus years of their rorting taxpayers moneys around the world for this scam. Now people are starting to wake up to them they’re bleating for more time(taxpayersmoney)
Has any one ever noticed that every time there is a new shampoo add on the box there is a new wonder ingredient that’s just been discovered that will change your hair forever?
These snake oil salesmen are no different.
What is sulfate aerosol particles?
And is this the reason I’m going to be paying a C/2 tax?
Or are there other reasons that the likes of Flannery and co will tell me? I’ve had enough.
I’m all fructosed out.
Give me a day, Anthony, and I’ll have a post comparing 17-year and 30-year trends (running) of models versus observations. The graphs are done. It’ll take a little bit of time to write it up with a introductory-level discussion of what the graphs are showing. As one would expect the models don’t do so good. This Santer post will make a nice lead in.
“The positive trend is quite close to the significance level. ”
Translation: The positive trend is not significant.
See William M. Briggs, Statistician, on how his Sample Size Extender™ will provide you a small p-value for any dataset you have: http://wmbriggs.com/blog/?p=4687.
There seems to be some confusion by some about looking for the anthropogenic fingerprint among the natural forcings. This is all about separating the human “signal” from the noise of natural forcings such as from ENSO, solar cycles (long and short), volcanoes, etc. Furthermore, some of that human “fingerprint” runs in opposition to itself (i.e. aerosols versus greenhouse gases, etc.). Finally, the 17 year period is a mininum time required to see the anthropogenic warming signal among the shorter-term noise, but it does not mean that even in that period, it would necessary show net warming. You could very well get a combination of shorter-term “noise” that still masks or counters the warming, but mathematically, 17 years is the minimum to be able to statisically be able to see the anthropogenic warming signal among the noise (even if there was no net warming during that period because the natural factors cancelled out any warming). Here’s an example of how this works: suppose you come home from vacation, and before you left you had turned you thermostat off. Before you left, it had been in the 70’s, but a cold front moved through just before you came home, and the temperature outside now is in the 40’s, and the temperature in your home is in the 50’s. You come home and turn your heater back on and set the thermostat to 70 degrees, and then head out to the store to pick up some groceries. You come back from the store an hour later, expecting to find a nice warm house, but it is still 50 degrees in your home. WUWT you ask yourself. You check your thermostat, and sure enough it is set at 70 degrees. You go downstairs and check your heater and it is running like crazy. Again, WUWT! Then you go upstairs to the top floor of your house and realize while you were gone, your teenager had opened all the windows in to “air out the stuffy house”. How would you have any “proof” that your home heater was working, other than to look at it running if the temperature in the home had stayed the same while you were gone? Only in looking at all the factors going in to the temperature in your house (open windows, temperature outside, heater running), could you come to any conclusioin as to why the temperature of the house is staying at 50 degrees. Related to increases in CO2 and the 17 year period to see the anthropogenic signal, it doesn’t really matter what the temperature does in the 17 year period (the probability is that it would go up, but it could go down as well, depending on other factors), but this is how long it takes to see the signal that the anthropogenic “heater is running”.
Tamino explains it all very well here…
If you remove all of the annoying bits (exogenous factors), the warming since 1995 magically becomes statistically significant and the cooling since 2001 becomes warming.
The HadCRUT3 cooling trend since 2001 will never become statistically significant. It will be massaged out of the data until we’ve clearly returned to Little Ice Age conditions by the end of this century. By then, the Warmists will have figured out a way to blame capitalism for the even worse climate disruption of global cooling… ;))
God (WMO) says 30 years. So there, Santer.
I say 300 years.
“the large noise of year-to-year climate variability”
Why not create a model capable of reproducing year to year variability. It would be interesting to see if the heat involved in El Nino and La Nina is great enough or whether other things must play a part such as average cloud cover or other shifting ocean pools and currents need to be called on to perfect the model.
Santer is pretty proud of “his” fingerprints being all over the IPCC reports and his “signature” work. The warming observed in the “results” does have a human element. This much is true. How much of it is Santer’s remains to be seen. Might be time to have a deeper look into Santer’s stuff.
The correct number is of course 42.
Maybe misreading this but isn’t Santer just assuming as a given that any long term (17 yrs (!)) upward signal is human induced ? i.e., no other cause contemplated or allowed? Surely there are longer timescale cyclic events and also the slow uplift post LIA, tho’ no mechanism seems to be posited for that (?)
I read the press release. It does not specify how they measured the human signal. I read implications that known, natural sources were filtered out, so whatever was left must be human.
The satellite data shows global temp dropping this year. When this data is folded in to their regressions, the warming won’t be quite so “close” to being significant.
Lets not get lost in all this statistics . If the puropose of collecting all this climate data is to make better weather forecasts for the near term first, then waiting for 1 7 years or 30 years to tell the public that the climate cooled or warmed has little value . I see much greater value to the public in more accurately recording and predicting better shorter term and better regional forecats , like seasonal numbers , annual numbers and decadal numbers. Kowledge about short term trends is more imprtant in our daily lives than knowing what the climate will be when none of us will be around . The fact that US has not warmed for 10-15 years is important and we should not wait another 15 [to reachl 30 years ] before we comment publically.It has taken nearly 15 years for the AGW climate scientists to tell the public what is happening and then they cannot even agree what happened , but they claim accuarcy 100 years and some have even tried 1000 years
Think beyond trend lines and other polynomial curve fitting with no predictive ability.
A simple equation based on the physical phenomena involved, with inputs of only sunspot number and ppmv CO2, calculates the average global temperatures (agt) since 1895 (that’s 115 years and counting) with 88.4% accuracy (an insignificantly lower 87.9% if CO2 is assumed to have no influence).
The equation, links to the source data, an eye-opening graph of the results and how they are derived are in the pdfs at http://climaterealists.com/index.php?tid=145&linkbox=true (see especially the pdfs made public on 4/10/10, 3/10/11 and 9/24/11).
As shown in the 9/24/11 pdf, the equation accurately predicted the temperature trends for the last 20 years.
The future average global temperature trend that this equation calculates is down. The huge effective thermal capacitance of the oceans (about 30 times everything else) will cause the decline to be only about 0.13°C per decade. The decline may be as much as 0.22°C per decade if the sun goes really quiet.
R Gates,
“but mathematically, 17 years is the minimum to be able to statisically be able to see the anthropogenic warming signal among the noise”
Oh come on. This 17 years is just a made up number to buy a few years more time. “Mathematically” indeed!
Given that even warmists concede that an anthropomorphic climate signal is so weak that it takes decades to be identified and quantified, doesn’t this rather undermine the catastrophic tipping point thesis?
“This makes it easier to identify a slowly-emerging signal arising from gradual, human-caused changes in atmospheric levels of greenhouse gases,” Santer said.”
It’s a slowly-emerging signal now is it, this AGW? Only last week they were shouting about unprecedented rates of warming. It’s funny, this AGW theory. It’s the only theory in science that morphs into a different shape every time it conflicts with real data.
Ben Santer eh? I think this is an opportune time to remind WUWT readers who this Ben Santer is.
The notorious chapter 8 of the 1995 IPCC report included the claim that there was “A discernable human influence on climate.” This claim was added to the report AFTER the meeting of the drafting scientists in Madrid Spain.
Who added the claim? Ben santer.
Where did he get the notion of a discernable human influence? From his own paper which wasn’t even published yet. And in that paper he profoundly cherry picked a time frame of data from sonde balloons.
The full explanation and graphs are at the below link.
http://www.john-daly.com/sonde.htm
This man has the cheek to claim sceptics cherry pick.
OK – let’s look at the past 17 years. (using the satellite figures as it covers the whole planet not just the land)
http://www.woodfortrees.org/plot/uah/from:1994/plot/uah/from:1994/trend
A warming trend of 0.14 per decade or 1.4C over the Century. Nothing significant and not even close to the computer predictions.
R. Gates says:
November 17, 2011 at 12:53 pm
Gates do you actually believe what you wrote? Do you? really do you?
Ben Santer’s trying to delay that Senate inquiry freight train as long as he possibly can.
R. Gates…is it difficult trying to justify a lack of warming with a cartload of technogarbage? How’s that consensus holding up?
Vince Causey says:
November 17, 2011 at 1:59 pm
R Gates,
“but mathematically, 17 years is the minimum to be able to statisically be able to see the anthropogenic warming signal among the noise”
Oh come on. This 17 years is just a made up number to buy a few years more time. “Mathematically” indeed!
———–
Wrong. Read the study before mouthing off.
Baa Humbug says:
November 17, 2011 at 2:12 pm
R. Gates says:
November 17, 2011 at 12:53 pm
Gates do you actually believe what you wrote? Do you? really do you?
———-
Tell me where I am in error, and why I shouldn’t.
The most important aspect of this press release is to identify at least six people to arrest and prosecute for fraud and theft of taxpayer funding immediately, and a whole host of others to begin to investigate for prosecutorial purposes in the long run. It will require that the statutes of limitation be extended to 17 years to bag them all. There’s an entirely new career path for aspiring tort lawyers.
“A single decade of observational temperature data is inadequate for identifying a slowly evolving human-caused warming signal”
“by roughly 0.9 degrees Fahrenheit since the beginning of satellite temperature records in 1979”
=============================================================
A full 1/3 of the record shows cooling…..
……and for the math challenged, 17 years is a little more than 1/2 the record, and almost all of that neutral or cooling
Obviously, 30 years is not what they want to see either……….
Climate scientists have argued that satellites have confirmed that the radiation spectrum is showing an increase in energy absorption in the CO2 bands over this period, and that the atmosphere is therefore “trapping” more energy, can they explain where the energy is being diverted to, since it isn’t warming the atmosphere. Claiming that a natural cycle is at play is fine, but the energy is either being held in a large reservoir (which noone has detected or measured any changes in) or it is being expelled from the Earth (and again it appears noone has detected any change). So where is the energy being held since it isn’t showing up in the atmosphere?
I’d argue that the “missing heat” needs to be found or the basic assumption that more energy is being trapped needs to be revisited.
A year or two ago the Skeptic commentary on WUWT and other skeptical orientated blogs were very defensive of the skeptical arguments regarding the source of the so called AGW and the skepticism that increasing anthropogenic CO2 was the cause of any significant global warming.
In the last year or so and particularly when i read the comments above, the Skeptic commentary has become increasingly derisory of the ever shriller and ever more desperate fear mongering claims of, and to use Richard Bett of the UKMet’s definition, the “climate change scientists” and the self promoting green climate change activists.
Skeptics have recently become increasingly cynical about the suspected and gross ulterior motives driving the claims of so many of the “climate change scientists”, and the shrill howls of outrage from the green lobby as their lavishly funded pet climate projects fall away as a jaded public turn their backs onto their increasingly desperate attempts to install a permanent “climate fear” psychology into the public psyche.
Within the last year the Skeptics have seen an increasing volume of evidence, including much more science based evidence plus ever more extreme quotes from warmists and the green climate activists plus an increasing volume of anti warmist anecdotal evidence from numerous sources to back up and reinforce their skeptiscm.
What a difference a year makes!
And Consensus!
What consensus??
Haven’t heard that word for quite a while now.
Baa Humbug says:
November 17, 2011 at 2:12 pm
R. Gates says:
November 17, 2011 at 12:53 pm
Gates do you actually believe what you wrote? Do you? really do you?
==========================================
Of course he does….
He believes that it would have been a lot colder, if it weren’t for “A” global warming….
…so cold, it would have erased all traces of “A” global warming
…and the temperature would be below where it was when we started
😉
“See phil Jones’ interview:
http://news.bbc.co.uk/2/hi/science/nature/8511670.stm
A – Do you agree that according to the global temperature record used by the IPCC, the rates of global warming from 1860-1880, 1910-1940 and 1975-1998 were identical?
So, in answer to the question, the warming rates for all 4 periods are similar and not statistically significantly different from each other.
Here are the trends and significances for each period:
Period Length Trend
(Degrees C per decade) Significance
1860-1880 21 0.163 Yes
1910-1940 31 0.15 Yes”
It is generally assumed that CO2 was not a major factor before 1945. So it seems as if nature was quite capable of producing warming trends of 21 and 31 years without any human influence. What am I missing here with regards to Dr. Ben Santer’s 17 years? It seems as if 31 years is not enough. I would suggest we wait 31 years to see if we get a definite signal and not spend a penny in the meantime on things that may not be necessary.
The lack of warming for 15 years followed by cooling for the last 7 years supports the assertion that the planet resists climate forcing changes (warming or cooling forcing changes) by increasing or decreasing clouds in the tropical region.
It should be noted that the so called “deniers” quote peer reviewed published paper that support the assertion that the planet’s response to any forcing change is to resist the change (negative feedback) rather than to amplify the forcing change (positive feedback).
The extreme AGW paradigm promoted by the IPCC requires that the planet amplify the CO2 warming forcing. Whether the planet’s response is to resist or amplify the CO2 greenhouse warming is the key fundamental issue.
No one disputes increases in atmospheric CO2 cause some warming.
It is curious that those promoting the extreme AGW do not discuss or acknowledge is a key fundamental scientific issue.
Seventeen years is just used to delay the obvious that many of us have known for ages. The goal post keeps changing because a number of alarmists won’t admit defeat, when it is staring them in the face. It is now 17 years because this is the longest period that the scare came about from. The world has only warmed for 17 years over the last 77 years and this cherry picked period is used to predict CAGW alarmist nonsense. When the minimum to determine a climate signal becomes longer than 17 years, no period with a greater length has any credibility because it becomes longer than the scare in the first place. Remember folks the scare first started in the 1980’s after a period of less than a decade of global warming.
Natural variation has currently dwarfed the climate changing CO2 signal. We have seen it before and we are seeing it now. The only problem with this theoretical approach, i.e.. we have had pauses in global warming before, does not address the unprecedented rise in CO2 we humans are causing, especially over the last 10 years. The Earth’s reported fever could be related to just bad surface temperature data; or, that the connection between CO2 and temperature via the trace gas radiative transfer model is…ah…imperfect. Or, and this is my thinking, that what is observed in the wet bench physics lab of CO2 and temperature is irrelevant to global atmosphere and its modulation between air and oceans. Maybe CO2 and temperature just aren’t important; other phenomena play a far larger role. Capricious connected oscillators may rule the day/night/seasons we observe.
17 years….The goldilocks number.
“In order to separate human-caused global warming from the “noise” of purely natural climate fluctuations, temperature records must be at least 17 years long, according to climate scientists.”
This is simply backward. Natural fluctuations are not noise, it is what it is. The man made signal, if any is the damn noise here. That is why it is so difficult to find. The operative is “if any”.
Gates’ post @12:53 pm is just Gates being Santer’s water boy. And of course, Santer is full of crap. Sixteen years, nine months is too short a time frame, but 17 years is OK?
Ri-i-i-i-i-ght.
Mr Gates, you are making an assumption that “it”, the anthropogenic signal, is there in the first place. If you cannot see “it” over the last few years you then assume that you need more time to see “it”. Either way AGW as a theory has been falsified. Either “It” is not powerful enough to counteract natural variation, or there are other natural factors now operating that were either ignored or were or are unknown or there are so many unkowns, including “it” that we cannot model climate. Your analogy is amusing but simplistic. Reality is complex and inconveniently unknowable. 2 more years of looking for “it” won’t help IMHO. 2 more years of payroll for Ben, Michael, Phil and Kev however is not amusing.
@ R Gates:
“How would you have any “proof” that your home heater was working, other than to look at it running if the temperature in the home had stayed the same while you were gone? ”
Well, R Gates. You could stick your hand out and check an air vent or radiator – a signal.
Plonk.
Where is your signal ?
Matt G; I think you have it spot on. They cannot go longer than 17 years or logic will fundamentally undo them – Check Mate!
I find the debate on this topic odd . I mentioned earlier that in my opinion we don’t have to wait 17 years or 30 years to find out where our climate is going . It is not a statistical issue. In my opinion man generated Co2 plays a very minor role here.What is significant is the 10-15 years of flat and cooling temperatures in US that Anthony pointed out. It is not insignificant as some are trying to suggest . It may be so statistically but in reality it is a very vital clue. Just look at the NCDC Contiguous US Annual temperatures graph 1895-2011 which shows that Contiguous US is about where it was 10 years after the 1934 warming peak . There followed about 10-12 years of declining or flat temperatures[ like we just had ] which in turn was followed by 30 years of much colder temperatures from 1950 to 1980 [which is what may lie ahead for US for the next 30 years .] The natural ocean cycles are about the same as then[temperatures are starting to decline ] In my opinion we need to pay more attention to shorter climate trends and shorter than 17 years or 30 years that the statisticians may want . Ten years of flat and cooling tempertures are very significant in my judgement.
Nick in Vancouver said:
“Reality is complex and inconveniently unknowable.”
———
? Reality is unknowable ?
Let’s not get too far into Plato’s shadows on the cave wall analogies here, but we can know “reality” well enough to create very precise and complex machines that manipulate matter at the quantum levels, even recently teasing out photons from nothing in the fluctuations of space-time itself. Our standard model of particle physics may not be complete, and is, by definition, never going to be, but works well and proves every day that our model for the “reailty” that is behind this world we perceive is accurate enough a map to be powerful and useful.
Kaboom says:
November 17, 2011 at 12:20 pm
“The positive trend is quite close to the significance level. ”
Fuzzy isn’t part of mathematics.
######
you do a test for trend.
the trend is .2C
the 95% CI is .2C +- .21C
the positive trend is quite close to the 95% significance level.
Fuzzy is a part of statistics. statistics is a part of math.
figure out what that means logically.
And then we can talk about how incompleteness, randomness,and undecideability are at the heart of math.
“what happens to the argument when we reach 2013-2014 and there’s still no statistically significant upwards trend?”
We can know that from Prof. Will Steffan’s reply to Andrew Bolt last Sunday: they will say that surface temperature is not important – all the heat is being stored up in the oceans. Of course there is no direct measure of the heat stored in the oceans but, they no doubt will argue, where else could all that heat trapped by anthropogenic CO2 be going?
You can’t beat this logic!
RiHo08 says:
November 17, 2011 at 3:32 pm
Natural variation has currently dwarfed the climate changing CO2 signal.
_______
You are hugely missing the point and understanding what “natural variation” means in terms of climate, and the related issue of signal versus noise. Climate is not a random walk. There are always forcings that cause the climate to warm or cool. Why do you think so much time has been spent by climate scientists trying to pin down why there was a flattening of global temps over the past decade? If it was just “natural variation”, or random noise, why bother looking at all? Just throw up your hands and say it was random noise in the climate! ENSO cycles, solar variation, volcanoes, human aerosols, all represent elements in what some would simply lump together as “natural variation”. And in claiming that “natural variation” having “dwarfed” the CO2 signal, you are assuming you know the total sum and level of those other forcings, down to what they mean in terms of negative watts/meter squared of cooling (plus positive feedbacks)on a global scale and compare that total to the warming effect in watts/meter squared (plus feedbacks) of 390 ppm of CO2. It could be (and I even suspect it) that we’d be looking at a Dalton minimum cooling period over the next few decades were it not for the additional CO2, as that rather cool time frame (early 1800’s) saw a similar quiet sun a period of high atmospheric aersols from volcanic activity. Instead, we may get a period of flat global temps, as CO2 is simply masking those cooling effects.
Nick in Vancouver says:
November 17, 2011 at 4:13 pm
Mr Gates, you are making an assumption that “it”, the anthropogenic signal, is there in the first place. If you cannot see “it” over the last few years you then assume that you need more time to see “it”. Either way AGW as a theory has been falsified.
____
If your house is staying at 50 degrees, even though your heater is on, it doesn’t falsify the theory that the heat ought to be heating your house. It simply means that something else is negating the effect of the heater. Might want to check and see if the there are a few windows open somewhere…
See:
http://wattsupwiththat.com/2011/01/05/on-%E2%80%9Ctrap-speed-acc-and-the-snr/#more-30992
Gates ignores the fact that CO2 has been extremely low at times when the earth was considerably warmer, and CO2 has been extremely high during times of global glaciation. The only evidence of correlation between CO2 and temperature shows that rises in CO2 follow rises in temperature, on time scales of months to hundreds of millennia.
It is apparent that CO2 isn’t “masking” anything. That is just a convenient excuse to avoid the fact that the temperature has not been rising, as had been universally predicted by the alarmist crowd, from Hansen to Mann to Santer to Trenberth, and everyone else on that side of the AGW fence. The more evidence that comes in, the clearer it becomes that CO2 is a minor bit player; CO2 isn’t masking anything, the minuscule effect of CO2 is what is being masked by other much stronger forcings and feedbacks.
Who should we believe, planet earth, or R. Gates?
R. Gates says:
November 17, 2011 at 5:17 pm
It could be (and I even suspect it) that we’d be looking at a Dalton minimum cooling period over the next few decades were it not for the additional CO2, as that rather cool time frame (early 1800′s) saw a similar quiet sun a period of high atmospheric aersols from volcanic activity. Instead, we may get a period of flat global temps, as CO2 is simply masking those cooling effects.
Oh really? I thought fluctuations in solar activity were too small to cause discernible differences (circa IPCC)? Or is that except when convenient?
good grief….we’re talking 1/2 a degree
Heater on, open windows….my hootie
No one would even notice if it weren’t for all the hysterical bedwetting going on……………..
R. Gates says:
If your house is staying at 50 degrees, even though your heater is on, it doesn’t falsify the theory that the heat ought to be heating your house. It simply means that something else is negating the effect of the heater. Might want to check and see if the there are a few windows open somewhere…
In the “CAGW” concept then, wouldn’t the onus be on the CAGW supporters to show why the house isn’t getting any warmer?
Wouldn’t a complete understanding of what both warms and cools the house be required?
Just wondering.
R. Gates.
The question is “how much” is CO2 influencing temperatures. I am not aware there is any answer, speculative or otherwise. The CO2 signal has not been separated from the noise. You may have proof in your own mind, I just can’t find it in the scientific literature. I would be happy if you would provide a citation. I am happy to reject any statement that the current hiatus is like prior hiatus simply because the current levels of CO2 are claimed to be unprecedented and elevated. If the CO2 temperature connection were real, for the global atmosphere, then the CO2 signal could be identifiable; which to my knowledge has not been so identified. Observations trump speculative climate models. No way around it. I am happy to await the sudden CO2 related jump in global temperatures after all the natural influences dissipate. Are you willing to wait?
From R. Gates on November 17, 2011 at 5:17 pm:
Well now, isn’t that a creative way of flipping the issue onto its head. ‘The proof of human-caused global warming will be that the global cooling could be much worse.’
That ranks up there with the current sulfates/aerosols debate: ‘The sulfate-based anthropogenic global cooling signal is masking the anthropogenic global warming signal!’ Excuse me, but doesn’t all that stuff add up to a total anthropogenic signal?
Meanwhile, in regards to Phil Jones’ ‘not statistically-significant’ 1995 to present line, just at the beginning of this year there was debate here on WUWT that with 2010 on the books, the global warming is now statistically-significant, just needed that extra year. So, what happened with that?
R. Gates;
Tell me where I am in error>>>
Thanks for opening the door on that. Before I start the list, interesting to see, yet again, that you only seem to show up on threads where the work of one of “the Team” is being questioned. All sorts of highly technical threads, and nothing from R. Gates. But poke at Trenberth’s work, or Mann’s, or Santer’s and…PRESTO! there’s R. Gates to defend them. One can only wonder why that is… but I digress, you wanted to know where you have been in error. Glad to oblige.
1. You agreed to wager regarding Al Gore’s on air experiment in that if it was replicated as illustrated, whether or not it would show the results illustrated. You bet it would, and I bet it wouldn’t. Anthony replicated the experiment, and you were proven wrong. Then you tried to change what the bet was about. Then you claimed that all the experiment showed was that the glass in the jars absorbs infrared. In short, you lost the bet and won’t admit it.
2. During our discussion of the experiment, you suggested that the globes be taken out of the glass jars as they were superflous to the experiment. I have pointed out to you repeatedly that with no globes in the jars, there would be nothing to absorb short wave radiation and re-radiate as long wave radiation. Your suggestion that the globes were superflous demonstrates that you do not undestand the first thing about the physics of the so called greenhouse effect.
3. You claimed in another thread that the “models” have always shown the possibility of warming taking a hiatus. I’ve repeatedly asked you which of the 23 models cited in the IPCC AR4 report made this claim. I’ve asked you where in the IPCC reports this suggestion was ever made. You’ve not responded.
Oh, I’m sorry, you meant where you were in error in THIS thread. My mistake. OK, let’s tackle that.
1. You’re example of the house and the heater and the thermostat and the windows is all fine and good, seems like you understand what a propogation delay is and you are trying to articulate it. Unfortunately, that has absolutely nothing to do with determining what period of time is required for climate data to be statisticaly valid.
2. You said, and I quote:
“but mathematically, 17 years is the minimum to be able to statisically be able to see the anthropogenic warming signal among the noise”
This is simply a statement, it is neither evidence nor proof. In order for your statement to have merit, you would have to provide the mathematical analysis to show this to be the case. You have not done so anywhere in your rambling remark. A statement that cannot be substantiated is at best misleading, and most likely contrived. If you cannot produce the mathematical analysis to back your claim up, then you cannot assert that the mathematics says anything one way or the other.
4. One cannot help but miss the desperation in your comment to find some plausible explanation for the hiatus in warming that is consistent with the alarmism around CO2. Suddenly, after years of insisting that the temperature was increasing and that natural variability had nothing to do with it, apologists for the misrepresentation of science by “the Team” such as yourself are suddenly blaming the lack of warming on… natural variability. Well OK, you mentioned man made aerosols as well. I was watching an old re-run of the sit com “Barney Miller” recently, which was what, late 70’s? The character “Fish” comes walking through the door wheezing like he’s about to die. Asked if he is OK, he quipped “its the smog. I swallowed a piece”. Much of the rest of the show features the cops wrestling with the fall out from yet another “smog warning” in New York.
tell me please R. Gates, when was the last time that joke would have been relevant? How often does New York have smog warnings like they did in the 70’s? How about Los Angeles? Any major European city? The fact is R. Gates that what China is ramping up isn’t a fraction of what the west has cleaned up.
you’ve no excuses to explain the warming hiatus that don’t also explain the warming that came previously. In other words, your whole explanation is wrong. Again.
“…10-year tropospheric temperature trends are strongly influenced by the large noise of year-to-year climate variability.”
I had the impression that, according to warmists, there was not “natural variability” as warming was trending steadily upwards. Sometimes theses guys forget what other colleagues said…
Why stop at 17 years? Let’s go back 1000 and we see there hasn’t been any warming, we’re close to the same as then. Let’s go back 2000, oops, most likely warmer then than now. So what’s the emergency again?
“…we reach 2013-2014 and there’s still no statistically significant upwards trend?”
How do you know what 2013-14 temperatures will be?
R. Gates says:
November 17, 2011 at 5:17 pm
“Instead, we may get a period of flat global temps, as CO2 is simply masking those cooling effects.”
You had better be right. A Dalton Minimum occurring at the possible end of the Holocene? It is, after all, half a precession cycle old now. Five of the last 6 interglacials have each lasted about half a precession cycle……..
“Therefore in constructing the antithesis, and taking into consideration the precautionary principle, we are left to ponder if reducing CO2’s concentration in the late Holocene atmosphere might actually be the wrong thing to do.”
The Antithesis
http://wattsupwiththat.com/2010/12/30/the-antithesis/
@Kaboom November 17, 2011 at 12:20 pm:
There are plenty of people here that know a lot more about this than I do, but at the least I would say the following:
Actually, quantum physics is all about mathematics and fuzzy. They’ve turned physics into a statistical exercise, due somewhat to Heisenberg’s Uncertainty Principle.
And from what I know of cosmology and astronomy, there is a whole lot of whoop-ass fuzziness going on there. And math is what is telling them that there is, for example, dark matter and dark energy – about as fuzzy as you’re going to get.
If we go around thinking that math is all about non-fuzzy, yeah, in high school.
And ALL linear regression is about uncertainty. Look at any properly done graph of historical data, and the farther back in time you look, the uncertainty bands get wider and wider – as in fuzzier and fuzzier. Almost no linear regression can give anything more than a probability that a future value will be within some minimum and some maximum. That is pretty much a clear picture of fuzziness, if you ask me. No pun intended…
David Middleton says: November 17, 2011 at 12:57 pm
Tamino explains it all very well here…
http://tamino.wordpress.com/2011/01/21/phil-jones-was-wrong/
http://tamino.wordpress.com/2011/01/20/how-fast-is-earth-warming/
David provides two excellent links with respect to temperature trend measurement where an attempt is made to back out the effect of ENSO, volcanic eruptions etc. Both are well worth reading. Executive Summary: temperature continues to trend upward.
“In fingerprinting, we analyze longer, multi-decadal temperature records, and we beat down the large year-to-year temperature variability caused by purely natural phenomena…”
Ahhh…you gotta love Ben’s way of expressing himself…”we beat down” LOL!!
I wouldn’t give this guy the time of day…
William McClenney says:
November 17, 2011 at 7:37 pm
“Therefore in constructing the antithesis, and taking into consideration the precautionary principle, we are left to ponder if reducing CO2’s concentration in the late Holocene atmosphere might actually be the wrong thing to do.”
———
Not at all an unreasonable question. As I am not currently a believer in catastrophic AGW, it is certainly a question I’ve pondered. Additionally, as many WUWT readers have pointed out, even if AGW is happening (as I believe it is), there may be more significant environmental issues that need addressing that have nothing to do with how much carbon we are putting into the atmosphere.
“kadaka (KD Knoebel) says:
November 17, 2011 at 6:27 pm
Meanwhile, in regards to Phil Jones’ ‘not statistically-significant’ 1995 to present line, just at the beginning of this year there was debate here on WUWT that with 2010 on the books, the global warming is now statistically-significant, just needed that extra year. So, what happened with that?”
Professor Jones should never have said this because almost as soon as he said it, it was already irrelevant. The anomaly for 2009 was 0.443. The anomaly for 2010 was 0.477. However the anomaly for the first 9 months of 2011 so far is only 0.358. So it is simple to do the math for the average for the last 21 months, namely 12(0.477) + 9(0.358) all divided by 21 gives 0.426. This is LESS than the 2009 value of 0.443. So in other words, the warming for the last 16 years and 9 months is NOT significant at the 95% level. And when the figures are in for all of 2011, we will have 17 years of warming that is NOT significant at the 95% level. If you do not believe me, see the graphics at:
http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/
Focus on the top 95% error bar for 1995 and note that it is way above the bottom error bar for the presently green 2011 line. It is so much higher that the green line cannot catch up any more for the remainder of the year.
“davidmhoffer says:
November 17, 2011 at 6:46 pm
1. You agreed to wager regarding Al Gore’s on air experiment in that if it was replicated as illustrated, whether or not it would show the results illustrated.”
You and R. Gates may be interested in the part below.
On a different post, this appeared. Very interesting!
BobM says:
November 17, 2011 at 9:02 am
Anthony, WUWT is also on my daily list. I’ve not posted any comments before but thought you might want to look at this: http://www.nyelabs.com/
Bill Nye admits “The Climate Project people created their own version, but apparently they didn’t test it very well. One of our strident climate change deniers seized on their corner cutting and showed their demonstration didn’t demonstrate anything.”
Most posts have missed an important concession by the Warmist authors: They admit the possibility of their models being wrong.
Prior to this, the Warmists and the IPCC have steadfastly clung to the (tenuous) claim that their plethora of models are infallible.
They just agreed to have the veracity of their models evaluated in about 4 years. Before, any attempt to examine or test their models were rebuked.
This is a very good sign that they are (subconsciously) admitting that they have lost any “high ground” they may have had, and are consenting to testing.
This implies that, deep down, they know that they have lost, and are hoping to stave-off the end-game for a few years, while they try to invent a new angle (spin) to again feed on Green Party largesse.
To delay the inevitable, they are doubling-down on their stupid bet lat CO2 is the climate’s forcing function.
Newt Love
Aerospace Technical Fellow of Modeling, Simulation, and Analysis
Great blog post and timely too. RSS data for 1996-2012 (17 years) shows no trend if one assumes a cold 2012. I’m sure Santer will rely on giss or some other dataset that gives him 5 more years, but this time next year will likely provide 17 years of no warming.
Santer (and R.Gates)…..the gift that keeps giving!
davidmhoffer says:
November 17, 2011 at 6:46 pm
David, I am not into basket ball but it is my understanding that your post would be referred to as a Slam Dunk? It is notable that he (R.Gates) is ignoring you again!
Be ever thoughtful of both facts and predictions before leaping to a conclusion. It was in fact a LEAP that terminated the last interglacial, the cold Late Eemian Aridity Pulse which lasted 468 years and ended with a precipitous drop into the Wisconsin ice age. And yes, we were indeed there. We had been on the stage as our stone-age selves about the same length of time during that interglacial that our civilizations have been during this one.
http://www.particle-analysis.info/LEAP_Nature__Sirocko+Seelos.pdf
So Santer has a 17 year itch … anybody know if he’s been to see a doctor?
In case you decide not to read it, here’s how it ends:
“The onset of the LEAP occurred within less than two decades (see the core photograph in Fig. 4), demonstrating the existence of a sharp threshold, which must be near 416Wm22, which is the 658N July insolation for 118 kyr BP (ref. 9). This value is only slightly below today’s value of 428Wm22. Insolation will remain at this level slightly above the inception for the next 4,000 years before it then increases again. Accordingly the model results predict a continuation of our present interglacial for the next 55 kyr (ref. 5), when insolation will decrease for the first time again to the LGI level. However, the Earthwill be in a fragile state for the whole of the next 4000 years, and one can only hope that the expected climate extremes of the Anthropocene will not lead to conditions that cross the threshold to glaciation.”
So, who can identify the human fingerprint in the latter curve? (except Dr. Santer)
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1945/plot/hadcrut3vgl/from:1975/to:2003
2011 is shaping up to be a cool year, at the bottom of the recent plateau, and 2012 looks to be even cooler. Once these two years are in the books, things will be more awkward for the warmists.
I read just yesterday, in the Guardian I think, some eejit saying that the idea of a pause in warming was nonsense – as proved by the fact that 2011 is looking to be one of the hottest 10 years on record!
Duh! If temps are flat for ten years after the hottest on record, isn’t it likely to be still somewhere close to the hottest year on record? Why is this so hard to grasp by the warmista?
Juraj V. says:
November 17, 2011 at 11:45 pm
So, who can identify the human fingerprint in the latter curve? (except Dr. Santer)
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1945/plot/hadcrut3vgl/from:1975/to:2003
Please Mr Gates, take up Juraj V on his request. While doing so be so kind as to further identify the period of 1948 to 1978, and show the human fingerprint there. Mr Gates, a keen but biased intellect can more readily assume an unbalanced position. The acronym for this is B.W.B.S. Your comments on this post are indeed more manure for the compost pile if you fail to respond to this query.
Can you find a mistake?
Simple equation calculates average global temperatures since 1895 (including the last 17 years) with accuracy of 88%. See it in the pdf made public 9/24/11 at http://climaterealists.com/index.php?tid=145&linkbox=true
R Gates,
“Wrong. Read the study before mouthing off.”
Forgive me for mouthing off – I mistakenly thought Anthony allowed freedom of speech on his blog, but obviously he must defer to a higher authority. Anyway, now that I’ve read the study, it all becomes clear – it was the model wot dunnit.
I can just picture old Ben with his screwdriver, tweaking the screw marked “time delay” until out pops a hiatus – of 17 years. “That’ll do” says Ben, and they all lived happily ever after. Any more fairy tales Gates?
From Santer’s paper, the climate models have the Satellite Lower Troposphere increasing at 0.23C per decade over the last 32 years.
The actual trend is 0.14C per decade (which would be closer to 0.10C per decade if one takes into account that two volcanoes early in the record made the trend higher than it would have been).
Santer 11 also says that once the Satellite trend gets below about 0.11C per decade, this will be a significant divergence. This could happen in a year or two if temperatures continue declining due to the La Nina (the La Nina might have to continue into 2012 to reach these numbers).
The 17 years, however, is really misdirection because the length of time required to prove significance is related to how far off the trends are to start with. 10 years would be more than enough if the satellites and real temperatures were showing -1.0C per decade for example.
Santer’s paper (below) is just a fine example of how just making up statistical formulae works perfectly well in climate science.
http://muenchow.cms.udel.edu/classes/MAST811/Santer2011.pdf
Hasn’t the stratosphere cooling been stopped for 17 years? What’s up with that, anyway?
Why, it has…
http://www.ncdc.noaa.gov/bams-state-of-the-climate/2009-time-series/stratosphere?del%5B%5D=hadat&del%5B%5D=iuk&del%5B%5D=raobcore&del%5B%5D=ratpac&del%5B%5D=rich
I only included satellite data, because the radiosonde data is shiesc, I think the word is.
Pete H;
It is notable that he (R.Gates) is ignoring you again!>>>
Well he’s kinda stuck now isn’t he? He’d look like a complete and total fool if he continues to argue his various positions, nor does he seem capable of simply admitting that he was flat out wrong. That leaves him with just one option which is to ignore me. I’m OK with that. It means I’m scoring points into an empty net.
And best of all, he hasn’t said boo about my observation that he only shows up in threads where people like Mann and Santer and Trenberth (especially Trenberth!) are being exposed or questioned in any way. Its almost like he’s got a job to do, so he grits his teeth and does the best he can with his limited tool set and hopes to collect whatever compensation it is that keeps him doing what he’s doing.
BWAHAHAHAHAHAHAHA!!!
It was natural variability in 1990.Then in 1995 it was a trace gas causing the warming.Then in 2001.It was a trace gas causing a developing catastrophic warming.Then in 2007 it was highly likely that it was us who is causing ALL the warming.
Throw in the numerous cherrypicking temperature trend complaints made by the warmists.The ones that might be 10 + years in length.But at the same time they and their common deceptive friend.The Media crow over a SINGLE weather even as proof of global warming (which never happened since 1979).
Now we have a man who may have started the corruption process in the IPCC.Comes up with a 17 year number.Since this will come back to haunt them and help further destroy their long dead AGW hypothesis.
Why bother continuing to make it so easy for rational people to laugh at you?
I didn’t see anyone mention this, so I will. Ben wants to establish the goal posts at 17 years? That’s fine. According to RSS…. in March of 2012 it will have been 15 years without any warming! http://www.woodfortrees.org/plot/rss/from:1997.25/plot/rss/from:1997.25/trend So, two more years? No problem. We’ve been at this game much longer than that. The clock is ticking. So, to the alarmists out there……. tick… tock….tick…….
I can certainly see why 17 years is the magic number needed to build a trend regarding the series of data used in the analysis. It is a statistical necessity in order to say that the trend is significant (IE outside the error bars). But a magic number says nothing about what is causing the trend. The trend is simply an average of weather pattern variations over the data series. It is not made up of “different” weather than the every day weather that is represented in the data. Weather data is a soup. Once it’s made, you can’t adequately remove and separate the stuff that made the soup, at least not in the data string discussed here. And the artificial trend line is even more “soup-like”.
The argument must stay focused on what causes changes in weather pattern variations. For that, the weather affects of natural short and long oscillations (which can be as short as two years and as long as 60+ years), and teleconnections between oscillations must be removed from the weather patterns observed. To do that we need a gold standard control period that is long enough to encompass these various oscillation patterns and that does not lay within the current CO2 rise. The long term recovery from the last ice age must be removed. And the even longer term axial tilt issue must be removed. I’m not worried about the Sun because that oscillation affects our ground temp very little (it is hard to get solar temperature affecting drivers through our atmospheric soup to any degree that could overtake the much stronger intrinsic drivers here on terra firma).
These important variables have not been presented strongly enough by AGW climate scientists. This glaring absence calls into question their hypothesis more than any other mistake they have made.
I should have also mentioned, if we were to use HadCrut……..we’ll have 15 years of cooling in June of next year. http://www.woodfortrees.org/plot/hadcrut3vgl/from:1997.5/plot/hadcrut3vgl/from:1997.5/trend ……. tick……..tock….
*****
William McClenney says:
November 17, 2011 at 10:53 pm
http://www.particle-analysis.info/LEAP_Nature__Sirocko+Seelos.pdf
*****
Thanks for the pdf — very interesting. Recommend it to everyone. Climate can & does change in mere decades. Makes our current warm, benign climate seem like paradise.
Ooh, he’s going to regret that – no later than 2015 I await a wuwt article with the title “Santer’s 17 years of cooling are here” 🙂
“Carl Chapman says:
November 17, 2011 at 12:12 pm
Why 17 years?”
My guess? Because the warming of the 80’s & 90’s was only significant over a 17 year period.
2013 News flash from AGW network.
Noise from 17 year Cicadian rythm drowns out statistically significant cooling trend. Scientists determine that 30 year trend required for statistically significant cooling, 5 years for warming.
Film at 11:00.
/sarc
The length of time needed to declare any cooling trend to be significant, will always be 2 to 3 years longer than the current cooling trend.
R. Gates says:
November 17, 2011 at 12:53 pm
—
The problem is that we don’t know what all the natural signals are.
So your claim that the human signal can be detected by subtracting the natural signals is nonsense.
Santer et al base their conclusions upon a psychological theory of how people make decisions under uncertainty; this theory is called “signal detection theory.” As a guide to making policy decisions, signal detection theory suffers from the shortcoming that people are prone to making decisions illogically. Interestingly, logic and Santer et al reach opposing conclusions about the merits of waiting until a period of 17 years has elapsed without significant global warming before concluding that the anthopogenic global warming hypothesis must be rejected.
In logic ( http://judithcurry.com/2011/02/15/the-principles-of-reasoning-part-iii-logic-and-climatology/ ) , a theory is a procedure for making inferences. The task of the theoretician is to build an optimal decoder of a message consisting of the outcomes from a specified sequence of statistically independent statistical events. Each of these events has a duration in time that is identical to the period of waiting. As this period increases, the number of observed statistical events that are available for training the decoder decreases toward 0 and the lack of information provided by the optimal decoder increases toward a maximum. At the maximum, determination of the current state of nature provides no information about the future outcome. For example, determination of the current CO2 level provides no information about the future global surface temperature.
The Hadcrut3 global temperature time series provides us with no more than about 12 observed statistically independent statistical events of 17 year duration but 12 events is by a factor of 10 or more too few for the training and statistical validation of an optimal decoder that provides any information at all about the outcome. The conclusion of Santer et al that there is merit in waiting for a period of 17 years is illogical for if we wait this long we will have no information about the outcomes of our policy decisions.
Pamela Gray,you said
“But a magic number says nothing about what is causing the trend.” You are quite correct . This what I tried to say earlier too. One of the key variables or causes of for the colder climate is the pattern of the amount of colder water in the Northern and eastern Pacific as indicated by PDO. The global cooling of temperatures seems to coincide with the declining PDO levels from peak to trough . The post 1934 , 10-15 cooling period started with dropping PDO levels which went negative by 1944. This was followed by a 30 year global cool period. Currently the post 1998, 10-15 year cooling period coincides also with a declining PDO readings which started its decline in 2003 and went negative in 2007 . Long term cooling of 20 to-30 years may again be indicated .People can wait for 17 years or even 30. To me statistical significance has very little to do with why a cooling trend is most likely indicated as a the key cause or variable better confirms what is probably ahead and there is historical patterns to support this.
A google image search for “Ben Santer” now contains the promo pic for Marilyn Monroe’s “The Seven Year Itch” and a link to this posting.
Congratulations!
It’s on page 2 and isn’t nearly as entertaining as the top line image of a cartoon baby crying its eyes out but still.
http://www.google.com/search?hl=&q=%22ben+santer%22&sourceid=navclient-ff&rlz=1B3GGHP_en___US455&ie=UTF-8&biw=1280&bih=615&sei=LqfGToKBJqOesQKjqvkj&tbm=isch
Santer says:
—–“Looking at a single, noisy 10-year period is cherry picking, and does not provide reliable information about the presence or absence of human effects on climate,” said Benjamin Santer, a climate scientist……
….. Think of 40 institutes with their Millenium forecast 2001 (TAR +SRES) on rapid global warming of 0.2 C per decade………they included everything in their models, they say….?
Now the newest SREX of Nov 2011, no more global warming for 30 years…..? This is the IPCC latest……what now, yes or no, warming no warming ……
Our models, our wonderful models, believe in the models and in CO2, not in nature, not in reality…..the models are the one and only truth. The AGW alarmists are the true scientists….
the sceptics are the the “anti-science people”…..
matt v. November 17 at 1:44pm
matt v. November 17 at 4:20 pm
matt v. November 18 at 11:00 am
Excellent comments matt. Easy to understand, and esy to remember the main points – in case I decide to honorably steal your comments; with the due credit, of course.
The first warmist commandment remains “Thou shall’t not doubt AGW …..ever”. (Despite any evidence to the contrary by evil AGW deniers) , So it wouldn’t matter if we had 20 years without warming ,these warmists would still be wetting their pants.
Why talk about only 17 years? It is demonstrated that change to the level of atmospheric carbon dioxide has had no significant influence on temperature for at least the last 115 years in the pdf made public 9/24/11 at http://climaterealists.com/index.php?tid=145&linkbox=true
davidmhoffer says:
November 18, 2011 at 5:24 am
“And best of all, he hasn’t said boo about my observation that he only shows up in threads where people like Mann and Santer and Trenberth (especially Trenberth!) are being exposed or questioned in any way.”
_____
I’ve commented more than enough on the points you continually want to bring up. Seems like you’re rather like a broken record. In terms of me “showing up”, I comment when something strikes my interest, but you’d like to read something more into it– which indicates even more to me that you are clearly rather good at fictionalizing reality.
MarkW says:
November 18, 2011 at 9:22 am
The problem is that we don’t know what all the natural signals are.
So your claim that the human signal can be detected by subtracting the natural signals is nonsense.
_____
No, not really. I suggest you read a bit more about global climate models before making such a overly broad statement. These are very sophisticated, and involve extremely detailed knowledge of atmospheric and ocean physics and dynamics. It is true that we don’t know the full details and feedbacks of the natural and anthropogenic signals, and with a dynamical chaotic system, we never will. But we certainly know the major forcing agents. But finding a the human fingerprint on the climate is not simply about subtracting the natural signals and finding out what’s left, but plugging into the models the dynamics and physics of what the human forcings ought to do, and seeing what the fingerprint ought to look like over a given period of time. The “subtracting” that you talk about is really about short-term and medium-term noise filtering (removing the effects of ENSO for example) so that you can see if the pattern the models tell you should be there is actually there.
R. Gates;
Just an observation my friend. If you could point out some threads that you’ve commented on that show otherwise, I’ll be glad to check them out and see if I am wrong or not.
As for commenting “more than enough”, well actually you haven’t. Oh you’ve commented all right, lots and lots of meaningless comments. But it doesn’t matter how much you say if you don’t answer the questions asked of you, or admit when your are wrong. You instead avoid, distract, come up with excuses, post links to immaterial articles, but answer the questions? Nope. Man up to the bet you made? Nope. Admit your errors? Nope.
And this comment is yet another fine example. If you had actually answered the charges I made, you could just cut and paste, or post a link. Instead you imply that you’ve answered when you have not.
Is that not rather disingenuous?
R. Gates says:
November 18, 2011 at 6:27 pm
…plugging into the models the dynamics and physics of what the human forcings ought to do, and seeing what the fingerprint ought to look like over a given period of time.
Ought to do in what environment? And how is that confirmed? Avoid the travesty.
R. Gates:
You talk of models, GCM’s. I can only adivse you to read section of of AR4. Carefully read each subsection, notice the certainty, and then add in the totals to the end product.
With the levels of uncertainty, the end product is really quite worthless.
A glariing example of models uncertainty is the stratosphere. It is not cooling, which indicates something wrong with the calculations of the models.
http://adsabs.harvard.edu/abs/2008AGUFM.A12B..01S
I can only encourage you to read the last line and think about the implications. Some would have you believe that the strat is still cooling. They are in la la land and deny the science.
“The phaseout of chlorofluorocarbons after the 1987 International Montreal Protocol now shows positive effects on ozone in the upper stratosphere. However, due to increasing CO2, the CCMs simulate a continuous linear cooling by 1~K per decade over the entire 1979 to 2010 period. This is not consistent with the near-constant temperatures observed since the late 1980s.”
“
R. Gates,
That is section 8 of AF4.
I wouldn’t want you to miss the opportunity to increase your knowledge.
R. Gates:
One more time I will try and type this correctly:
Section 8 AR4.
I think I got it this time.
R. Gates:
I would also have you note that the time frame of the observations exceeds 17 years. With that in mind, the GCM need to be revised to show the proper responses to the strat concerning the radiative powers of co2. Something is wrong here.
Strat not cooling, longer than 17 years. What else is wrong with the models that is concerning to all?
Camburn,
The pdf made public 8/11/10 at http://climaterealists.com/index.php?tid=145&linkbox=true shows some of what is wrong with the models.
The above seems somewhat related to the following (2009)
http://www.nytimes.com/2009/09/23/science/earth/23cool.html?_r=2
”
Underscoring just how little clarity there is on short-term temperature fluctuations, researchers from Britain’s climate change office, in a paper published in August, projected “an end to this period of relative stability,” with half the years between now and 2015 exceeding the record-setting global temperatures of 1998.
”
[I have not seen the paper itself.]
If we use HadCru3
http://www.cru.uea.ac.uk/cru/data/temperature/hadcrut3gl.txt
then I guess the correct number to use is the last column—annual anomaly-{I think—please correct me if I am wrong}.
For 1998 it is ..548. No number below it is even close (2005 is .482) and it is clear that 2011 will also not be close.
This leaves 4 years 2012-2015 to beat .548 three times. It seems unlikely.
I guess if it does not happen the Hadley center will close its model and announce that all papers based on it are now meaningless :>).
All this fuss about warming is based on SURFACE temperatures (ie: those usually measured about 54 inches above concrete, asphalt, and maybe grass). What about the remaining 99+% of the atmosphere that resides more than 4-1/2 feet above grade? Is it not obvious where the bulk of temperature measurement must be made to get a more representative sampling of the atmosphere’s condition?
In the absence of a quest for such knowledge in this area, one can only conclude that temperatures above the surface DO NOT support global warming theory. If they did, we would not be hearing the end of it.
“rdr200 says:
November 19, 2011 at 10:30 am
This leaves 4 years 2012-2015 to beat .548 three times.”
And if you check the NINO 3.4 Ensemble Forecast on WUWT, it goes to August and the highest one does not even reach 0 in all this time, so if the La Nina persists until then, there is no hope that 2012 will set any record.
Thank you very much for that link where it says:
“the odds of a 15-year pause, they wrote, are only 5 in 100”
If there are no drastic changes, and I do not expect any with the present La Nina forecasts, that point will be reached on HadCrut3 next May.
I wonder if this then means they will be only 5% sure that CO2 causes any warming?
I think some people are missing the point here: If there’s lots of year-to-year variation, as there is with the global average surface temperature (due to El Nino, the solar cycle, volcanic activity etc) then short time series are very unlikely to show statistically significant upward trends in global temperature. That doesn’t mean there isn’t a long-term upward trend, just that the sample size is too small to yield statistical significance. If you include more years in the analysis, the trend becomes statistically significant.
Those who don’t believe that anthrogenic CO2 emissions are causing a rise in global temperatures need to explain what other mechanism has caused the clear rise in global temperature over the last 150 years, and need to put forward sophisticated models with a high degree of predictive skill to back up their arguments. However, they have so far clearly been unable to do either of these things. In contrast, the evidence for anthropogenic global warming is compelling, if you care to read it with an open mind.
Rob Nicholls (Dec. 2, 2011 at 2:22 pm):
One thing we don’t have from the proponents of AGW is “models with a high degree of predictive skill.” The IPCC’s climate models make projections of global temperatures and not predictions. While often confused, projections and predictions are different concepts.
Hi, it has already been done: Transparent calculations for everyone to follow, easy to understand,
never refuted or rebutted, just correct to the last number….. please see booklet ISBN 978-3-86805-604-4, available for 12 EU at the German Amazon. de…… Therefore,
no more ridiculous assumptions please, that skeptics cannot figure out global warming/cooling mechanism. My book even shows how to meticulously calculate the mechanism of “Dansgaard-Oeschger events”,
which is exactly the same warming/cooling mechanism as of today. None of the Warmist bunch with all their recent collutions (Climategate 2) is able to do this…..
The author JS.
As for the “significance level” of any flat or warming or cooling period, the Team keeps (apparently successfully) trying to convince the world that 95%, or in a pinch 90%, confidence levels constitute “statistical significance”. Given the huge zoo of potential biases and contamination of data and analyses, this is outrageous. And given the cornucopia of free (fudgable) parameters in the models, almost certainly also mendacious.