Tamino (aka Grant Foster) will have his knickers in a twist over this one.
Guest post by Marcel Crok (from his blog De staat van het klimaat)
An interesting new paper (behind paywall) has been accepted for publication in the Journal of the Atmospheric Sciences. The paper by Jiansong Zhou and Ka-Kit Tung of the University of Washington, Seattle is titled “Deducing Multi-decadal Anthropogenic Global Warming Trends Using Multiple Regression Analysis”.
This paper will add fuel to the recent discussions about the nature of the global warming trend and whether it recently has stabilized or not. The authors by the way conclude it has not. Their main conclusions however is:
When the AMO is included, in addition to the other explanatory variables such as ENSO, volcano and solar influences commonly included in the multiple linear regression analysis, the recent 50-year and 32-year anthropogenic warming trends are reduced by a factor of at least two. There is no statistical evidence of a recent slow-down of global warming, nor is there evidence of accelerated warming since the mid-20th century.
This study is following the same approach as Foster/Rahmstorf 2011 and Lean/Rind 2008 (trying to correct the global temperature for ENSO, solar and volcanoes) but adds the Atlantic Multidecadal Oscillation to their multiple linear regression analysis. This leads to their figure 1b above. What we see is a longterm trend that has hardly changed during the past century.
Now as always this result can be interpreted in many different ways. The century scale trend is still 0.68 degrees Celsius suggesting little of the total trend of 0.8 degrees C can be attributed to solar, volcanic, ENSO and AMO. That’s what the authors seem to suggest as well when they write (bold mine):
The conclusion that we can draw is that for the past 100 years, the net anthropogenic trend has been steady at approximately 0.08 °C/decade.
So for them anything that’s left after filtering out the natural forcings and natural variability is just ‘anthropogenic’. For me this conclusion is rather premature. But before I explain why let’s focus on the other trend lines that the authors show. Just like Foster/Rahmstorf they conclude that there is no slowdown recently:
There is no statistical evidence of a recent slow-down of global warming
However the trend they find for the recent 32 years (0.07ºC/decade) is far lower than that of Foster/Rahmstorf (0.17ºC/decade). If the approach has any validity at all this would suggest that the AMO alone explains the difference between the Zhou/Tung and Foster/Rahmstorf trend.
The paper by Zhou claims that in the last 32 years, the period in which greenhouse gases are supposed to be the dominant forcings, in fact some 60% (0.1ºC of the total 0.17ºC/decade) of the trend can be ‘explained’ by a combination of ENSO, AMO, solar and volcanic forcing). Ergo, only 40% of the trend could be attributed to other factors among which greenhouse gases are of course a logical candidate.
However there are other candidates as well of course. There is ongoing debate about the influence of siting issues on the temperature measurements on land as well as the Urban Heat Island effect and other socio-economic influences. In a controversial and well known paper Michaels/McKitrick estimated that “Using the regression model to filter the extraneous, nonclimatic effects reduces the estimated 1980–2002 global average temperature trend over land by about half.” If true even less of the remaining trend can be attributed to greenhouse gases.
The Zhou study could therefore have serious implications for our estimates of climate sensitivity. The paper though is completely silent about these potential implications, something that reviewers could have raised.
As said above Zhou and Tung call the remaining century long ‘underlying’ trend ‘anthropogenic’. Whether this is ‘right’ could be questioned with their figure 2 (see below). Here one sees that the anthropogenic forcing (green line) seems to underestimate the adjusted trend in the period (1889-1970) while it seems to overestimate the trend thereafter. This suggests that still not all the relevant factors (either natural or anthropogenic forcings or natural variability) are included in the regression analysis. The residuals in figure 2b still show trends which would not be the case, Zhou and Tung write, if the regression analysis would be perfect.
This leaves enough room for all to bend the paper in one’s preferred direction.
======================================================
Deducing Multi-decadal Anthropogenic Global Warming Trends Using Multiple Regression Analysis
| Abstract |
|---|
In order to unmask the anthropogenic global warming trend imbedded in the climate data, multiple linear regression analysis is often employed to filter out short-term fluctuations caused by El Nino-Southern Oscillation (ENSO), volcano aerosols and solar forcing. These fluctuations are unimportant as far as their impact on the deduced multidecadal anthropogenic trends is concerned: ENSO and volcano aerosols have very little multi-decadal trend. Solar variations do have a secular trend, but it is very small and uncertain. What is important, but is left out of all multiple regression analysis of global warming so far, is a long-perioded oscillation called the Atlantic Multi-decadal Oscillation (AMO). When the AMO Index is included as a regressor (i.e. explanatory variable), the deduced multi-decadal anthropogenic global warming trend is so impacted that previously deduced anthropogenic warming rates need to be substantially revised. The deduced net anthropogenic global warming trend has been remarkably steady and statistically significant for the past 100 years.
Since the AMO trend (or North Atlantic SST record) for 1910-1945 and 1975-2005 is exactly the same, I do not get from where they got those 40 and 60%.
Why do they split the trend at 1970?
A linear trend is a model. If after 1970 a new model is required the only possible reason is the increasing influence of antropogenic greenhouse gases. But then, calling the trend for the previous period an “antropogenic” trend is inexplicable. And all that the added greenhouse gas accumulation would cause is the difference in slope between the two trends, about 0.15 deg C in 40 years or 0.0375 deg C/decade.
The Zhou study could therefore have serious implications for our estimates of climate sensitivity. The paper though is completely silent about these potential implications, something that reviewers could have raised.
==========
The paper is likely silent on purpose. To avoid the firestorm of controversy that would have resulted if they were to questions the orthodoxy. Such an action, to questions scientific beliefs, is to commit scientific heresy. The punishment is to have ones career burned at the stake.
Natural oscillations in the North and the South hemispheres run out of phase. To do a proper job two should be treated separately, and then recombine to observe the global change, but I suggest it would be preferable to present separate graphs first.
This sort of thing reminds me of papers on naturopathy. The herb is first assumed to be therapeutic, the experiment shows an elevated level of some molecule in the bloodstream, and the conclusion of the paper is that the elevated level must cause the therapeutic effect. There is not much difference with saying that the reason our curves don’t overlay perfectly must be AGW.
It starts with HADCRUT4. It doesn’t really matter how much infinitesimal meaning they can squeeze out of that, because they start with HADCRUT4.
This paper appears to make the same blatantly obvious error as Foster and Rahmstorf (2011). It assumes the effects of ENSO can be removed from the instrument temperature record through linear regression. They cannot.
http://bobtisdale.wordpress.com/2012/01/14/revised-post-on-foster-and-rahmstorf-2011/
It also fails to account for the very obvious long-term impact of ENSO on the sea surface temperatures of the North Atlantic. Note how the detrended North Atlantic sea surface temperature anomalies do not cool fully during the La Nina events that follow the El Nino events of 1986/87/88 and 1997/98:
http://i48.tinypic.com/ndldht.jpg
Boooh! No more research funds for you… 😉 Sorry, I couldn’t resist.
How did they account for UHI when determining the anthropogentc warming signal? Land use changes from human activity are not properly taken into account.
The AMO is defined as a linearly detrended North Atlantic sea surface temperature (SST). See the AMO index page at http://www.esrl.noaa.gov/psd/data/timeseries/AMO/
Subtract regional temperature (affected by solar, volcanic, ENSO variations) from global temperature (affected by solar, volcanic, ENSO variations), and amazingly enough your signal goes away. The differences are quite small – http://tamino.wordpress.com/2011/01/30/amo/
It will be very interesting to see what their regression coefficients are like – my suspicion is that the AMO will dominate as highly correlated, as changes in the AMO index are driven by those same solar, volcanic, and ENSO effects, and will encompass them.
Matt Skaggs says:
October 17, 2012 at 7:33 am
Pedantic rant:
A molecule is an assemblage of atoms. In this context, for a molecule to be elevated implies a place, e.g. in the head rather than the foot.
An elevated level of some chemical implies a greater number of molecules in one sample versus another.
“Chemical” has been added to the non-politically correct view of the world reserved for horrible pollutants like carbon dioxide. Personally, I like to think I’m full of chemicals, though I confess I have more molecules than chemicals. Chemistry is like that….
Solar, ENSO, AMO and volcanic signals have been removed, dropping the total in half.
The CAGW IPCC narrative says that these other influences are not significant, or less than about 25% (from the leeway I see they give themselves). The paper challenges the assumptions, not the record.
The CAGW enthusiasts would argue that this paper doesn’t change a thing about their stride to reduce fossil fuels. It is the total thermal impact of man and nature that counts. Man can only moderate his part, and with that part moderated or removed, the temperature rise comes to not be “catastrophic”.
So this paper could be used to support the Gore-Hansen-Suzuki screed: take the “known” elements out of his study, and man must be the problem!
According to my findings the AMO (9-10yr) is driven by difference in the phase between solar oscillations and the Earth’s magnetic ripple.
http://www.vukcevic.talktalk.net/EarthNV.htm
A similar process may be driving the ENSO (4.5-5yr) but with near double frequency,
http://www.vukcevic.talktalk.net/ENSO.htm
The AMO is by far more dominant in the N. Hemisphere.
Both oscillations have much longer period component.
Including the AMO as an explanatory variable is a mistake. My own work indicates that global temperature Granger-causes the AMO, not the other way around. Their regression is spurious.
The authors’ conclusion:
If the residual trend has been remarkably steady for the past 100 years that is proof that it is NOT anthropogenic.
Can’t be sure without access to the full paper, but it sure LOOKS as if they did not include GHGs in their regression analysis:
What the hell? That’s not legitimate in the least. Their “regression” does not include the what they are contending is pointed to as the main explanatory variable. As a result, we have no idea from their analysis how much explanatory power GHGs have and how much residual or “unexplained” error there would be.
Crazy. And from the link I see that Forster and Rahmstorf did the same thing. In my field of economics regression analyses are done all the time and I can guarantee that no economist would ever even conceive of the idea of not including their proposed explanatory variable in a regression. That’s the whole point: to get a statistical measure of the explanatory power of the variables one is looking at. Maybe if CO2 data were not available you would try to estimate its explanatory power indirectly by controlling for other variables, but CO2 data IS available.
I think we can be certain that they did run their regression with CO2 included and just aren’t showing us the results. After all, It’s a matter of a few minutes work to pull up a CO2 time series and add it to the regression. Here, I’ll time myself, starting at 10:45AM PDT. Law Dome, 10:46 AM PDT:
http://www.ncdc.noaa.gov/paleo/metadata/noaa-icecore-2455.html
So the authors definitely ran the regression with CO2. They just don’t want to show us how the residual error from their published regression gets divided between unexplained error and an estimate of the explanatory power of CO2, instead pretending that unexplained error IS the estimated explanatory power of CO2.
Can FOIA be used to prove that they did in fact run the regression with CO2? If so, I think this would be a proven case of scientific fraud. These guys are at the University of Washington so maybe it’s doable. But before I go too far with this accusation, maybe post-author Marcel Crok can give us some more detail on what is in the pay-walled paper. Is the impression from the abstract correct? Have they really left GHGs out of their regression? If so, do they offer any rationale?
Yet another regression. An interesting one, but that doesn’t make it right. I don’t think it’s significantly different from many other regressions I have seen so far, including those made to “feed” climate models.
The “anthropogenic forcing” regression is clearly regression to CO2 concentrations, hence the shape. Reduced portion of CO2 influence on climate may be due to last 16 years of warming “stall” because that made the regression to favor natural cycles more than in earlier regressions made for models when this stall wasn’t there.
I don’t wonder they don’t mention implications on climate sensitivity – it would sure make the review process a whole lot more complicated.
Barton Paul Levenson says:
October 17, 2012 at 10:54 am
Including the AMO as an explanatory variable is a mistake. My own work indicates that global that global temperature Granger-causes the AMO, not the other way around. Their regression is spurious.
—————————-
What causes “global temperature” to go in 50 year up and down cycles then?
You’re right back at north Atlantic ocean cycles then.
Don’t think they include the slow rise in temperature due to recovery from Little Ice Age, or the very long-term effects of the deep Thermohaline ocean currents which could be warmer now following the MWP heating event, May also be other omissions?
The paper is weak as it fails to include all climate drivers and its conclusions are, therefore, less than convincing. I can give this one a ‘C’ at best.
Here is my own model of Hadcrut4 on a monthly basis (versus annual that this paper uses I assume).
Too close to be a fluke – and my warming rate is only 0.045C per decade on a linear rate (although 2.0*Ln(CO2) provides a closer fit or 1.3C per CO2 doubling)
http://s19.postimage.org/gg5zqvvrn/Hadcrut4_Model_Aug_2012.png
60% are they kidding, it is just about 100%, co2 having 0% effect on the climate, which wil be proven before this decade ends.
this paper is useless more or less, even though it sides against co2 but it is hedging all over the place and doesnot adress why the climate changes and how, which I do ,which will be on my web-site in the very near future.
This paper like almost evey other single paper wants a silver bullet. Now it is the AMO,tomorrow it will be the PDO, then it will be volcanic eruptions, then it will be the thermohalinec circulation.
No concept as usual, that in order to understand the climate one has to take a major comprehensive approach to the subject, this kind of an approach is a waste of time.
I am done.
This is another typically useles IPCC type paper which ab inito assumes “Solar variations do have a secular trend, but it is very small and uncertain.” There is no reason to read any further than that statement. before safely ignoring the rest.
“regression analysis is often employed to filter out short-term fluctuations” … It would seem to me that most of our weather and climate are made up of short term fluctuations, to discount them is like putting blinders on. If the volcano didn’t happen, if the Ocean fluctuation didn’t exist. .. Instead of figuring out why they exist science picks and chooses what it wants to include. Blinders with a carrot in front . . . that’s what that is.
These kind of studies make me want to scream. I am really to upset to write anything of significance right now. Of course they believe in AGW, that is why the whole thing is ridiculous. Idiots!
Okay, I must have gotten left behind. I thought that the predicted trend from the GCM models was 0.2 deg. C/decade as of now. The actual warming from approximately 1880 to now–the known record–was about 0.8 deg. C. Now this paper’s residual trend from “just” CO2 is 0.08 deg. C./decade; or just about exactly what we have experienced over the last 130 years?
I’m thinking I must be wrong about them Zhou and Tung failing to regress on CO2. I think their “anthropogenic warming” line must be their C02 regression coefficient times the CO2 time series.
Zhou and Tung ,no nothing about climate, and they show that to be the case in their stupid study.
I am going to do just a very breif outline on what runs the climate to show these fools ,how clueless they are.
Zhou and Tung, here is how it works. It starts with the sun, that is the engine that drives the climate. It is like what gasoline is to a car engine. When the sun undergoes variations in solar irradiance ,solar wind speed or UV light emissions, and geomagnetic activity on the earth,those in turn have an impact on the atmosphere,due to the fact that those solar variations modulate ozone, cosmic rays and visible light ,along with having an impact on gelogical activity, through the ap geomagnetic index. Those in turn effect items such as the atmospheric circulations such as the nao/ao/pna/aao , so2 concentrations,oceanic circulations or phases such as the pdo/amo,and ocean heat content. Those in turn effect items such as enso,arctic sea ice,snow cover ,clouds, precip., which in turn effect the overall albedo of the earth, which utimately effects the temperature.
The reason why temp. have been on a rise since the Dalton Minimum (fools) is because solar activity as measurend by the aa index has been on a dynamic rise throughout that entire period until 2005 unfortunately for you. Since 2005 the sun has gone from a very active phase (1850-2005) to a very quiet phase, which is why the temperature trend has leveled off, and which is why the trend wil be down. The reasons why this is not happening faster are due to ocean heat content lags,which had 150 years of an active sun to gain heat, and the weak max of solar cycle24, both of which will become less of a factor as we move forward through this decade.
The amo,enso and volcanic activity within themselves having nothing at all to do with the temp. rise last century(in the whole big context of things) ,much less co2 which has a negative corrrelation to temperature trends to begin with.
That is , but a very brief rebuttal to your ridiculous study, now that I have calm down some.
S de Prete: co2 having 0% effect on the climate, which wil be proven before this decade ends.
BPL: It doesn’t. Earth is habitable because it has CO2 in its atmosphere. Venus is uninhabitable for the same reason. The difference is the amount.
and geomagnetic activity on earth changes, as a result of solar activity,
Also no should be know. I did this in a slam bang fashion. Sorry .
Tamino (aka Grant Foster) will have his knickers in a twist over this one.
What? Do the men in the USA wear knickers? But it is interesting to see this phrase being used. For more examples of British phrases which, apparently, are being used in the USA see:
30 of your Britishisms used by Americans
http://www.bbc.co.uk/news/magazine-19929249
Coming in at number 15 is Knickers
Barton Paul Levenson:
At October 17, 2012 at 3:01 pm you say
Well, a bit of that is right.
As you say, Earth is habitable because it has CO2 in its atmosphere.
But at present levels of atmospheric CO2 concentration additional CO2 in the atmosphere has no discernible effect on the Earth’s climate.
And the CO2 in the atmosphere of Venus is not relevant to the climate of Venus which is a net emitter of radiation.
Richard
I meant from this level, where all of the effects of co2 as far as absorbing long wave radiation are at or very close to the saturation point, therefore adding additional co2 (from this level)will have very little further effects, on the temperature.
it is like a sponge soaking water, once it reaches saturation ,it has very little further effect in soaking up more water.
There paper in reality supports the global man made warming hoax, it is not, as it is made out to be.
“The deduced net anthropogenic global warming trend has been remarkably steady and statistically significant for the past 100 years.”
—
What caused AGW 100 years ago? And if the deduced net warming trend has been “steady” for the past 100 years, why are we constantly being told that warming trends, sea levels, and CO2 levels are “accelerating.”
Barton Paul Levenson says:
“BPL: It doesn’t. Earth is habitable because it has CO2 in its atmosphere. Venus is uninhabitable for the same reason. The difference is the amount.”
Yes, the “amount”: because the amount makes the Venusian air so dense you could swim in it (if the heat would wait a bit before burning you up). It is definitely the adiabatic lapse rate due to the “amount” – air pressure, not some property of CO2 specifically.
“It is definitely the adiabatic lapse rate due to the “amount” – air pressure, not some property of CO2 specifically.”
It is fairly easy to demonstrate that the temperature difference between Earth and Venus at the same pressure density is solely accounted for by distance from the Sun, not the composition of the atmospheres.
http://theendofthemystery.blogspot.com.au/2010/11/venus-no-greenhouse-effect.html
A similar calculation can be done comparing the Earth’s temperature of -40C at 70,000m where the atmospheric pressure is the same as the Martian surface. The difference between the -40C and the -64C at the surface of Mars is accounted for by the greater distance of Mars. No other variable is required.
Anthony, the ‘snipe’ at Tamino is unworthy of you and your goals.
I’m aware of the history of bad blood between the two of you. I know it’s hard to always be the better man. Especially when it feels like its not being recognised. Yet the civility that you have always insisted upon has contributed to your blog being the most widely read climate blog in the world, and his an also-ran.
I’m no partisan of Tamino’s. You, Anthony, have published my every comment on your blog, whether I agreed or disagreed with the poster. Tamino did not publish my only comment on his site. Amusingly, in the comment he deleted, I was badly mistaken, and he and his supporters could fairly have made much of my error. So I have reason to be pleased he did censor me- but I am affronted by that he did.
Yet as a sincere admirer of yours, I tell you- that line is a mistake.
Augggh! A century-long anthropogenic trend? These two authors have just disqualified themselves from any claim to scientific sentience.
“n a controversial and well known paper Michaels/McKitrick estimated that “Using the regression model to filter the extraneous, nonclimatic effects reduces the estimated 1980–2002 global average temperature trend over land by about half.” If true even less of the remaining trend can be attributed to greenhouse gases.”
1. Thats the LAND 30% of the surface.
2. That well known paper has huge data errors. I’ve alerted Ross to them. For example in his regressions he has the population of alaska set as the same as new york city. And has millions of people living in antarctica. Basically he set the population of every grid cell to be the total population of the country divided by the grid cell area. That leads to silly things like french Islands having huge populations and the gobi desert having the same population as Bejing.
I Talked about this on Judiths. Pretty much devastates the paper.
Ross says via mail that he is looking for better data. opps.
next.
KR says:
October 17, 2012 at 10:06 am
my suspicion is that the AMO will dominate as highly correlated, as changes in the AMO index are driven by those same solar, volcanic, and ENSO effects, and will encompass them.
That certainly matches my findings:
http://tallbloke.wordpress.com/2012/10/17/phil-jones-we-dont-know-what-natural-variability-is-doing/
Dr Norman Page says:
October 17, 2012 at 12:22 pm
This is another typically useles IPCC type paper which ab inito assumes “Solar variations do have a secular trend, but it is very small and uncertain.” There is no reason to read any further than that statement. before safely ignoring the rest.
Quite so. If it is uncertain, how do they know it’s small?
Bill Illis says:
October 17, 2012 at 11:41 am
Here is my own model of Hadcrut4 on a monthly basis (versus annual that this paper uses I assume).
Too close to be a fluke – and my warming rate is only 0.045C per decade on a linear rate (although 2.0*Ln(CO2) provides a closer fit or 1.3C per CO2 doubling)
http://s19.postimage.org/gg5zqvvrn/Hadcrut4_Model_Aug_2012.png
Hi Bill,
I’m getting a correlation for monthly data of R^2 =0.873 for my model against HADsst3 from 1876 (start of AMO and SOI data)
http://tallbloke.files.wordpress.com/2012/10/sst-model1.png
No volcanics or SAMO in my model, and the sensitivity is is 1.6*ln(co2)
Solar forcing is bigger in my model, but I can get around the same correlation by changing co2 and solar forcings. You can make anything out of the data within the bounds of uncertainty.
Now that solar is going down as co2 continues to rise, we should find out in a few years time whether solar or co2 is the bigger driver.
Wow, inflation has been worse than we thought.
With Mosher complaining about the Michaels/McKitrick paper, in his no-links cryptic fashion where his arguments are somewhere over at Judith’s, I went to go Google the paper.
It was published at the end of 2007, and now he’s suddenly discovered all these flaws?
I found a January 2008 mention, with a link to the abstract “…where nonsubscribers can purchase the PDF for $9.00…”
Now they want $25 for it! A 278% markup in just five years!
I blame Obama.
BTW, Dr. Pielke Sr has the links for the pre-print version, the follow-up, and their data.
figure 2b could be the most informative. After removing their estimate of “anthropogenic” the is a marked down turn after 1970 (just about the same time as the anthro signal becomes significant).
Since all we know about climate has been taken out at this stage , such change in direction either means there was a fundamental change in climate around that time that is being missed or that one or more of the factors that is being removed is/are grossly in error.
That’s the objective over view, now let’s apply Occam’s razor.
This discrepancy starts at about the time the “anthro” signal becomes significant. The deviation of the upward red portion in 2a from the blue trend is about half magnitude of the deviation of the downward red portion in 2b.
Now if we calculate the anthro signal with a climate sensitivity of unity (as would require the physics at the exclusion of hypothetical positive feedbacks that have no observational basis) that up tick would have one third the slope shown in 2a.
The net result would be something very similar to the blue trend continuing undeterred through out the record. In which case, all the sub-century variations have been accounted for.
This paper is probably the clearest indication I have seen so far that demonstrates from global data that the hypothetical GHG _amplification_ is an error.
This paper seems to present strong evidence that climate sensitivity is near unity.
A corollary of the above is that the warming injected by the ENSO signal is cancelling volcanic cooling. I have proposed elsewhere on this blog that ENSO is acting as a negative feedback and correcting the heat loss of volcanic cooling within ten years.
I observed this in the rate of change of OHC, the present paper seems corroborate the idea starting from surface data.
The recovery can be seen in the residual from detecting cyclic variation and removing them
http://i49.tinypic.com/2vjqvpl.png
Alex Rawl says:
>>
Can’t be sure without access to the full paper, but it sure LOOKS as if they did not include GHGs in their regression analysis:
When the AMO is included, in addition to the other explanatory variables such as ENSO, volcano and solar influences commonly included in the multiple linear regression analysis…
What the hell? That’s not legitimate in the least. Their “regression” does not include the what they are contending is pointed to as the main explanatory variable. As a result, we have no idea from their analysis how much explanatory power GHGs have and how much residual or “unexplained” error there would be.
Crazy. And from the link I see that Forster and Rahmstorf did the same thing. In my field of economics regression analyses are done all the time and I can guarantee that no economist would ever even conceive of the idea of not including their proposed explanatory variable in a regression. That’s the whole point: to get a statistical measure of the explanatory power of the variables one is looking at.
>>
That’s a very good point. If they included the anthropological signal in the regression it would probably get weighted by about 1/3, in line with what I pointed out above.
Tenuk says:
October 17, 2012 at 11:36 am
Don’t think they include the slow rise in temperature due to recovery from Little Ice Age, or the very long-term effects of the deep Thermohaline ocean currents which could be warmer now following the MWP heating event, May also be other omissions?
That is very likely what the remaining blue trend in figures 2a and 2b represents. The do not seem to have modelled it explicitly but it is what is left after accounting for all the sub-century variation.
ferd berple says:
October 17, 2012 at 7:11 am
The Zhou study could therefore have serious implications for our estimates of climate sensitivity. The paper though is completely silent about these potential implications, something that reviewers could have raised.
==========
The paper is likely silent on purpose. To avoid the firestorm of controversy that would have resulted if they were to questions the orthodoxy. Such an action, to questions scientific beliefs, is to commit scientific heresy. The punishment is to have ones career burned at the stake.
Yes, I also got the impression they were saying as much as they dared without ensuring the paper got refused. I think there is some important results in there and they did not want t jeopardise the paper by being too clear about what the implications were.
Calling the century scale trend anthropogenic seems more than odd.
“The conclusion that we can draw is that for the past 100 years, the net anthropogenic trend has been steady at approximately 0.08 °C/decade.”
This seems contradictory to labelling the green line which is not constant anthropogenic.
Overall I think the paper could have significant implications for climate sensitivity as it seems to present the blatant deviation caused by current assumptions of amplification in figure 2b.
2a and 2b really invite the reader to notice that there is NO amplification.
Richard: at present levels of atmospheric CO2 concentration additional CO2 in the atmosphere has no discernible effect on the Earth’s climate.
BPL: No. It’s up 40% since the industrial revolution began. It’s the absolute amount that matters, not the concentration. The nitrogen, oxygen and argon that make up more than 99% of Earth’s atmosphere is not radiatively active.
R: And the CO2 in the atmosphere of Venus is not relevant to the climate of Venus which is a net emitter of radiation.
BPL: No, Venus is in thermal balance. You may be thinking of a report a few years ago that Venus radiates 40 times what it receives in the infrared. But that’s not true for the whole electromagnetic spectrum.
Wrong approach, the correct approach is looking at the correaltion between the aa geomagnetic index and the temperature response on earth. Let’s base it on a 1910 value.
time period avg aa index temp value
1900-1920 14 1910 value
1980-1996 27 +.6c
Maunder Minimum 0 to 12 -.6c
That is the correct approach, all this other talk is garbage.
time period – 1900-1920 ap average index 14 temp 1910 value
time period – 1980-1996 ap average index 27 temp. value +.6c
maunder minimum ap average value 0-12 temp. value -.6c
Barton Paul Levenson:
I am ignoring the invitation to debate the climate of Venus although that would be interesting. WUWT has a severe troll infestation today and discussion of Venus would be a disruption to this thread which is about the Earth’s climate.
I am replying to the statement in your post at October 18, 2012 at 7:15 am which says
It seems you are unaware that the IR absorbtion of CO2 in the atmosphere is constrained to only two narrow bands with almost all being in the 15 micron band. These bands are so near to saturation that they only increase their absorbtion by band broadening.
Think of light (i.e. visible radiation) entering a room through a window. If you put a layer of dark paint over the window then much light is absorbed by the paint and, therefore, does not enter the room. Add another layer of paint and more light is absorbed by that layer, but not as much as by the first layer. Similarly for each additional layer of paint.
The IR emitted from the Earth’s surface is trying to pass the ‘window’ of the atmosphere to enter space. Adding more CO2 to the air is like adding more paint on the window that has seven layers of the paint. Each unit addition of CO2 has less absorbtion than the previous unit addition: this reducing effect is logarithmic.
Empirical – n.b. not model-derived – determinations indicate climate sensitivity is less than 1.0deg.C for a doubling of atmospheric CO2 equivalent. This is indicated by the studies of Idso from surface measurements
http://www.warwickhughes.com/papers/Idso_CR_1998.pdf
and Lindzen & Choi from ERBE satelite data
http://www.drroyspencer.com/Lindzen-and-Choi-GRL-2009.pdf
and Gregory from balloon radiosonde data
http://www.friendsofscience.org/assets/documents/OLR&NGF_June2011.pdf
If climate sensitivity is less than 1 deg.C for a doubling of CO2 equivalent, then it is physically impossible for the man-made global warming to be large enough to be detected because natural variability is much, much larger. If something exists but is too small to be detected then it only has an abstract existence; it does not have a discernible existence that has effects (observation of the effects would be its detection).
As you say, the concentration of CO2 in the air has increased by ~40% since the industrial revolution (i.e. from ~280 ppmv to ~390 ppmv). This takes the degree of absorbtion of CO2 to ~80% of a doubling of CO2 in the atmosphere because of the logarithmic effect. And the globe has only warmed about 0.8deg.C since the industrial revolution. Most – if not all – of this rise is certainly recovery from the Little Ice Age (LIA), but if it is assumed the entire temperature rise is from the CO2 increase then a further increase to reach double pre-industrial concentration (i.e. to ~560 ppmv) would only provide a further increase to global temperature of about 0.2 deg.C. And a further doubling of atmospheric CO2 (to 1,120 ppmv) would only raise global temperature by an additional 1.0 deg,C.
In summation, as I said, at present levels of atmospheric CO2 concentration additional CO2 in the atmosphere has no discernible effect on the Earth’s climate.
Richard
One can see the strong correlation, and once the aa index falls below sub 5 ,which it will, once this maximum of solar cycle 24 passes by, because we are in a prolong solar minimum period, the temp. will show a more definitve down trend.
Ocean Heat Content lag holding back things ,but the accumulation of sub-solar years is increasing up to 7 ,and the ohc should become less of a factor going forward, since it is visible light which contributes to the ocean heat content ,not infra-red light. Co2 absorbs infra-red light(15 microns) it does NOT absorb visible light.(.5 microns). Infra-red light having ZERO effects on OHC.
Co2 is a non player. We have the perfect set-up for global cooling. We want a warm amo, we want less arctic sea ice, because these two factors will aid in driving the atmospheric circulation toward a more meridional circulation(-ao/-nao),with the main factor being prolong minimum solar activity(due to ozone distribution changes between high latitudes versus lower lat. in the uppe rtrop/lower stratosphere) but those two factors will aid in accomplishing this.
A meridional atmospheric circualtion is going to drive down the N.H. temp. or at least distribute the temp. profile in such a way that the latitudes 30n-65n are going to be colder, and probably the whole hemisphere colder as a whole, although latitudes above 65n could be more or less the same.
This is the correct path, all this other talk about amo temp correlation,co2 ,volcanic activity ,enso,pdo, apart from eveything else as if THEY are the ONLY factors is a waste of time.
All those except for co2 do play a part, an important part, but it has to be evaluated in the contex of the overall picutre. You can’t isolate them,everyting is interconnected and it starts and is driven by the sun.
Again the sun is to the climate, like what gasoline is to a car, it drives the climate, and influences all the parts that make up the climate, to give an end result.
This paper is just ridiculous, written by these two, and the IPCC is a joke.
should be aa average, although ap and aa are almost the same. I meant to use aa
nah?, what did I tell you. It is just going to get colder and colder.
It will take another 4 years before we have “bottomed out”.
http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures/
stop worrying about the carbon. Start getting worried about the cold.
Can you remove ENSO and AMO by linear regression? Is this a valid approach?
S del Prete: I meant from this level, where all of the effects of co2 as far as absorbing long wave radiation are at or very close to the saturation point, therefore adding additional co2 (from this level)will have very little further effects, on the temperature.
BPL: It’s not saturated at the upper levels, and warming anywhere there will propagate down to the surface. It’s easy to demonstrate if you want the math.
RH: Yes, the “amount”: because the amount makes the Venusian air so dense you could swim in it (if the heat would wait a bit before burning you up). It is definitely the adiabatic lapse rate due to the “amount” – air pressure, not some property of CO2 specifically.
BPL: No. You would have the same lapse rate whatever the surface temperature, because the adiabatic (“dry”) lapse rate is solely a function of the local gravity and the specific heat of the air (cp rather than cv). With less CO2 in the air, Venus would be cooler, its atmosphere would not reach as high for the same pressures, but the lapse rate would stay the same.
By using the AMO index, this paper essentially adds the 60-year oscillation observed in the climate system to previous regression models that did not contained it.
Too bad that the authors did not references any of the previous works that essentialy did the same and arrived to a similar conclusion that recent anthropogenic warming trend (since 1970) needs to be cut about by half.
Just my works are here:
Scafetta N., 2010. Empirical evidence for a celestial origin of the climate oscillations and its implications. Journal of Atmospheric and Solar-Terrestrial Physics 72, 951-970.
Loehle C. and N. Scafetta, 2011. Climate Change Attribution Using Empirical Decomposition of Climatic Data. The Open Atmospheric Science Journal 5, 74-86.
Mazzarella A. and N. Scafetta, 2012. Evidences for a quasi 60-year North Atlantic Oscillation since 1700 and its meaning for global climate change. Theoretical Applied Climatology 107, 599-609.
Scafetta N., 2012. A shared frequency set between the historical mid-latitude aurora records and the global surface temperature. Journal of Atmospheric and Solar-Terrestrial Physics 74, 145-163.
Scafetta N., 2012. Testing an astronomically based decadal-scale empirical harmonic climate model versus the IPCC (2007) general circulation climate models. Journal of Atmospheric and Solar-Terrestrial Physics 80, 124-137.
Scafetta N., 2012. Multi-scale harmonic model for solar and climate cyclical variation throughout the Holocene based on Jupiter-Saturn tidal frequencies plus the 11-year solar dynamo cycle. Journal of Atmospheric and Solar-Terrestrial Physics 80, 296-311.
Scafetta N., 2012. Does the Sun work as a nuclear fusion amplifier of planetary tidal forcing? A proposal for a physical mechanism based on the mass-luminosity relation. Journal of Atmospheric and Solar-Terrestrial Physics 81-82, 27-40.
Look at my web-site or details.
http://www.duke.edu/~ns2002/#astronomical_model
Of couse the present paper does not explain what it the physical cause of the 60-year AMO oscillation. This issue is also addressed in my papers by finding it among the natural oscillations of the solar system.
Will: It is fairly easy to demonstrate that the temperature difference between Earth and Venus at the same pressure density is solely accounted for by distance from the Sun, not the composition of the atmospheres.
BPL: Then why is Mercury, which is much closer to the Sun, cooler than Venus by almost 300 degrees?
Nicholas Scafetta, is on the basic correct path. I agree with his basic assumpitons.
The problem with Nicholas Scafetta, is he is under estimating the natural forces that will be at work on the climate system, and falling for the AGW hoax to a degree. So his temperature projections wiLl be way to high going forward.
Another problem with Mr. Scafetta, although I agree with his basic assumptions ,is he does not seem to have a grasp on all the secondary effects which will come into play if solar conditions should meet certain critical threshold values, for a long enough sustained period of time, following years of sub-solar activity prior to these values being attained, and years of prior very active solar actiivty (1850-2005) before the sub-solar activity which started in year 2005. This all comes into play. It is all part of the puzzle.
Also the earth’s magnetic field strength will have a role in this.
Barton Paul Levenson:
I began my post addressed to you at October 18, 2012 at 8:04 am by saying
Reviewing your subsequent posts in the thread I can only conclude that sometimes it is hard to put a good troll down.
Richard
PS It does not matter what your “calculations” say because empiricism trumps theory: read my post which I cite in this post.
Barton,it is not happening as evidence by the amount of outgoing long wave radiation being emitted from the earth out to space. It is NOT decreasing.
Also if this was happening we would have seen evidence of stratospheric cooling,again this is NOT happening.
Warming will propogate to the surface, I don’t think so. Don’t work that way.
From Scafetta, to these two that wrote this paper, just about everyone does not approach the climate situation in a comprehensive enough manner. I have 17 categories for the climate and I keep them all updated with data, and how it applies or does not apply to a possible change.
The only persons I have come across that really has this situation down our Joe D’Aleo ,and Joe Bastardi both of weatherbell..
SdP: Warming will propogate to the surface, I don’t think so. Don’t work that way.
BPL: Sure it does. Warm objects radiate. A warmer high level of air radiates in all directions, including down to lower levels. Why wouldn’t it?
R: It does not matter what your “calculations” say because empiricism trumps theory
BPL: Which physical law, based on empirical observation, do you disagree with? Stefan-Boltzmann? Wien? Kirchhoff? The ERT? What empiricism, in particular, trumps calculations of mine you haven’t even seen yet?
Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object. This precludes a perfect refrigerator. The statements about refrigerators apply to air conditioners and heat pumps, which embody the same principles.
This is the “second form” or Clausius statement of the second law.
Alternative statements: Second Law of Thermodynamics
Index
Second law concepts
Heat engine concepts
HyperPhysics***** Thermodynamics R Nave
Go Back
Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object. This precludes a perfect refrigerator. The statements about refrigerators apply to air conditioners and heat pumps, which embody the same principles.
This is the “second form” or Clausius statement of the second law.
Alternative statements: Second Law of Thermodynamics
Index
Second law concepts
Heat engine concepts
HyperPhysics***** Thermodynamics R Nave
Go Back
My point ,co2 does not create energy or better is not a source of energy, so how could heat flow down from a colder body the atmosphere to a warmer body the earth’s surface???.
Barton , I bet you could kill me in math any day of the week, but I hope you will look over what I had to say today in my many post about the climate and why so many of the articles don’t do it any justice.
I hate to keep picking on Nicolas Scafetta, but he ignores abrupt climate change completly, because that does not fit into his cycles. I can’t take anyone to seriously that does not address abrupt climate change. Abrupt climate change being ever present (many many times in the past) and happening as quickly as a decade,or less sometimes.
I address this issue in detail. Infact absolutely none of the papers visit this vital topic, especially the one done by these two so called experts.
Barton Paul Levenson:
At October 18, 2012 at 3:23 pmyou say to me
The “calculations” are those which you mentioned at October 18, 2012 at 10:42 am where you wrote
“The math” must be wrong because the ‘Hot Spot’ is missing.
I agree with all the physical laws. But I am not an idiot so I know that attempting to apply physical laws to a complex and partially understood system usually provides wrong answers. And the empirical evidence clearly shows your assertion is wrong. Simply you have done some sums to assess what you think is how the climate system works but reality demonstrates the system is nothing like you think it is.
Try applying physical laws to calculate the behaviour of the human brain and see what you get: the climate system is more complex than the human brain. (And don’t try to use that illustration as an excuse to troll the thread about brain structure).
Richard
The hotspot in the lower trop. near the equator no where to be found another big blunder. I am glad you mentioned that. Where is the so called positive feedback between co2 and water vapor. Answer missing in action.
Here is another big blunder. They, the models said the atmospheric circulation index would become more positive with time, guess what it is becoming more negative with time.
I have over 30 blunders they ,the models have made. They are in a word ,useless.
Salvatore del prete says:
October 18, 2012 at 4:01 pm
I hate to keep picking on Nicolas Scafetta, but he ignores abrupt climate change completly, because that does not fit into his cycles.
*************
See dear Salvatore, for taking into account “abrupt climate change” dynamics one needs first to find an event that can be interpreted as such. Excactly, in the last 160 year since 1850 where and when do you see “abrupt climate change” dynamics that needs to be taken into account with appropriate non linear models?
I don’t understand why you just go back only 160 years?
I will say this, we know abrupt climate change has happened many times in the past ,it is the norm not the exception. If anything the last 160 years are the exception, in that the climate has been in more or less one particular regime, with variations in the climate in that particular regime due to the cycles you suggest. They work fine when the climate is more or less in a particular regime, but will not hold up when an abrupt climatic event takes place, which is when, not if.
I think in order to really have a really complete understanding of earth’s climatic system this abrupt climate change issue has to be addressed.
Going back 160 years to 1850 ,I would say ther were zero events or sequences of events were present during that time period ,which would promote an abrupt climate change, hence we had no abrupt climate changes post 1850.
We had a steady active sun, with a more or less rhythmic 11 year sunspot cycle in place, we had no exceptional geological activity, earth’s magnetic field showing no unusal weakness(although it is weakening),we had an average more or less atmospheric circulation, which more or less resulted in cloud cover,snow cover and precipitation to be ranged bound. Variations yes but within a range, which were governed by the cycles you suggest which were also range bound during this time period.
Then when the beginning state of the climate is applied to the solar ,geological ,atmospheric circulatioin, ocean cycle variation, parameters, we had at that time up to year 2005, one can see why the climate was so steady ,or I should say within a particular regime.
However post 2005, this in my opinion is no longer the situation. The potential now for the first time since 1850 exist for a more rapid climate shift or change, due to this prolong solar minimum ,that commenced in year 2005.
We have had so far 7 years of sub -solar activity ,and prior to that we had 150 years of more or less very very active solar activity. Just look at the aa index, how it increased during the last century, which can be correlated to the the temperature rise.
Now we have a prolong solar minimum which is going to cause sigificant changes in solar wind speeds, uv light emissions, and geomagnetic activity on earth. These solar changes if strong enough in degree of magnitude and duration of time ,and if following enough years of prior sub-solar activity, could cause the climate system of earth to reach critical threshold values which could for lack of a better word flip it into another climate regime, or at the very least bring a significant change to the current state, the climate has been in for the past 150 years.
One must appreciate all the secondary effects that come from changes in solar parameters,(solar wind,uv emissions,solar irradiance) ranging from changes in ozone, cosmic rays, geological activity, ocean circulation patterns,ocean heat content, etc etc, which in turn have effects on the atmospheric circulation,so2 concentrations, clouds, precipitation,snow cover etc. etc,, which in turn will effect the albedo of the earth,(especially the n.h) and if not the temperature dropping per say, at least a different distribution of temp. in the N.H.,due to an atmospheric circulation which is set up to be more meridional then it has ever been ,probably since the Dalton Minimum. The set-up is in due to the abrupt change from a very active sun to what we have now, and the low amounts of Arctic Ice, the warmish Arctic in general ,the warm AMO, which are a compliment to the the sun’s role in promoting a more meridioanl atmospheric circulation due to changes in ozone distributions.Not to forget a substancial increase in high latitude geological activity (volcanic activity)which will further promote a more meridional atm. circualtion ,while increasing (causing cooling)so2 concentrations. Increase geological activity beng correalted to weak solar and weak earth magnetic fields.
I maintain a meridional atmospheric cirulation if maintained long eough, and to a degree strong enough wil have profound climatic impacts,especially for the N.H.
That is all I want to say,I could go on much longer but don”t have the time, but I think you can get the jest of where I am coming from,from what I did say.
Your work is good, but it upsets me to no end when you think the AGW cause ,is going to almost balance out the natural causes that will be impacting the climate going forward. It almost cancells out all your great work. Co2 has zero effect on the climate at these levels.
Also you yourself said an albedo change of 1 to 3% could occur, if that is the case, you would be suggesting a much greater fall in the overal temp. of the earth then what you actually forecast,never mind distribution changes in the temperature of the earth, especially in the N.H.
Your work in the solar areas is sensational, I have to say among the best I have ever seen, you know way more then I could ever hope to know in that paricular area. The best.
BPL 10/18 12:07pm: “Then why is Mercury, which is much closer to the Sun, cooler than Venus by almost 300 degrees?”
Because Mercury has only a trace GHE. Venus GHE acts on heat flow due to its huge atm. emissivity. Absent GHEs effect on heat flow, find Mercury surface hotter than Venus surface.
No GHE, 0 emissivity: Venus surface Teq. = 232K
No GHE, 0 emissivity: Mercury surface Teq. = 456K
———————————————
The math: w/basic, idealized radiation 1st principles where e=emissivity of atm.
Compute planet net solar irradiance S from total solar radiant energy So: S = So*(1-albedo)/4
Find Teq at surface spread over entire planet from: Teq ^4 = S/(c*(1-e/2))
Mercury avg. So ~10,404 W/m^2, albedo = 0.068, find S = 2,424 W/m^2
Mercury avg. Teq. = 456K for 0 emissivity of trace atm. (actual Tmin. ~100K, Tmax. ~700K)
Use same eqn.s w/Venus data find Teq. = 232K for 0 emissivity (non-GHE) theoretical atm.
QED: Mercury Teq. hotter than Venus Teq. w/no GHE.
Add in Venus actual atm. emissivity GHE +500K find Venus hotter mean Tavg. = 732K.
—————————————–
Compare Earth avg. orbit radius So ~ 1369 W per m^2, albedo ~ 0.30, find S ~ 240 W per m^2.
Using eqn.s in paragraph above & no warranty for typo.s:
c = Stefan-Boltzmann constant
e = radiative emissivity of planetary atmosphere averaged over emission spectrum;
set e = 0 for no infrared-active gases (commonly non-GHG), compute Teq for Earth = 255K,
reset e = 0.8 for actual infrared-active gases ppm in Earth atm. to get Teq = 288K
So BPL can see math for where the Earth GHE comes from (288K – 255K = 33K GHE)
Venus closer sun orbit, albedo ~0.75, e=0 non-GHG shows 232K (~732K – 232K = 500K GHE).
Mars further from sun orbit, albedo 0.25, e=0 non- GHG shows 210K (~215 – 210 = 5K GHE).
I believe Salvatore may well be right in suggesting the sharp drop in solar magnetic field strength in 2005 as a possible sign of coming abrupt climatic change. The resulting secular increase in incoming cosmic rays is well illustrated in the Oulu neutron data. Go to http://cosmicrays.oulu.fi/#database and generate a plot beginning Feb 15th 1998 – present.
It starts at the 22/23 minimum which is the maximum for incoming GCRs. Compare this with the 23/24 minimum (GCR maximum) in Dec 2009. Also look at the levels of GCR near the 23 solar cycle peak (GCR minimum) cf the curent levels which are close to or at least about 1 year short of the 24 maximum (GCR minimum). The 23/24 Dec 2009 GCR max is beyond anything seen in the modern era and in line with the Livingston and Penn data suggests a possible sudden plunge into a Maunder type minimum possibly via an increase in cloud cover and increased albedo.
richardscourtney says:
October 17, 2012 at 3:33 pm
And the CO2 in the atmosphere of Venus is not relevant to the climate of Venus which is a net emitter of radiation.
I’m afraid you’ve been misinformed Richard, for reference the cloud tops on Venus have an IR brightness temperature of ~237K.
GCR, just beng one of the many impacts to the climate system from a prolong solar minimum condition. There are many .
It is a new ball game post 2005. Why someone like Nicholas Scafetta, who knows his solar so well,reaches the temperature forecast he does, does not add up given what he knows.
Here is something that might help. Go to this web-site ICECAP.COM, then click, about climate change, then look under topic historical perspective. You will see something titled the Greenhouse Score Card. This essentially takes a look at over 30 predictions the models made on the climate in regards to co2 and the resulting effect expected, and scores each of the predictions based on the data since the model prediction was made.
Almost (98%) all the model predictions have been proven to be wrong.
His temperature projection (nicholas) does not make sense, especially given the fact he admits albedo changes of up to 3% could result from solar changes. A 3% increase in albedo equals about a 1.3 drop in temperature. It does not add up.
1.3 centigrade drop in temp
One last item, is one has to appreciate the rise ocean heat content underwent from around 1960-2005, due to the strong solar activity ,again look at the aa index. Ocean Heat Content takes a long time to wind down, and this is what is currently keeping the temperatures higher then they would be otherwise,( along to solar cycle 24 max. to a lesser degree) both ocean heat content and solar 24 max .wil become less and less factors as this decade proceeds.
If this prolong solar minimum condition as Nicholas Scafetta says is going to go on to the 2030’s , I just don’t see how the temperature will hold up to his projected levesl which in my opinion are much to high. I think the average temp. drop for the N.H. by decade end will be around -1.2 C, with the biggest drops over land areas between 30n -65 n., and drops less then -1.2 c elsewhere. Polar areas may for example remain unchanged.
salvatore del prete says:
However post 2005, this in my opinion is no longer the situation. etc….
****************************
Ok, we will see what will happen. However, from 2005 to now my prediction is holding well.
See my figure here:
http://www.duke.edu/~ns2002/#astronomical_model_1
http://www.duke.edu/~ns2002/scafetta-forecast.png
I agree with your prediction up to 2005. I don’t expect much of a temp. decline until the maximum of solar cycle 24 passes on by. As weak as it is, it is still generating moderate solar activity, way to high for the low solar values I am looking for to have a climate impact. That should pass however once this maximum is over and done with. I say post 2014 or 2015.
Surprisingly some of “the team” have made some quasi empirical calculations of the Maunder effect on climate
“Shindell et al. 2001
Shindell, D.T., G.A. Schmidt, M.E. Mann, D. Rind, and A. Waple, 2001: Solar forcing of regional climate change during the Maunder Minimum. Science, 294, 2149-2152, doi:10.1126/science.1064363.
We examine the climate response to solar irradiance changes between the late 17th century Maunder Minimum and the late 18th century. Global average temperature changes are small (about 0.3° to 0.4°C) in both a climate model and empirical reconstructions. However, regional temperature changes are quite large. In the model, these occur primarily through a forced shift towards the low index state of the Arctic Oscillation/North Atlantic Oscillation as solar irradiation decreases. This leads to colder temperatures over the Northern Hemisphere continents, especially in winter (1-2°C), in agreement with historical records and proxy data for surface temperatures.”
These numbers would fit quite well with the paper recently discussed on WUWT
http://www.academia.edu/1515229/The_extra-tropical_Northern_Hemisphere_temperature_in_the_last_two_millennia_reconstructions_of_low-frequency_variability
Salvatore — looks like you and I are on the same page – I agree completely with your 12.26 post.
No doubt – great minds think alike.
Phil:
re your post addressed to me at October 19, 2012 at 10:56 am, I refer you to the body of my much earlier post at October 18, 2012 at 12:38 pm.
Richard
R: “The math” must be wrong because the ‘Hot Spot’ is missing.
BPL: I think you’ve conflated two different issues here. The question is whether a warmer upper layer of atmosphere would in turn warm a lower layer. It would. Again–want the math?
Trick, what’s “GHE?”
S de Prete,
My information is that the models have made seventeen correct predictions. I have a list of them, with references for each prediction and each later confirmation:
http://bartonpaullevenson.com/ModelsReliable.html
richardscourtney says:
October 19, 2012 at 2:12 pm
Phil:
re your post addressed to me at October 19, 2012 at 10:56 am, I refer you to the body of my much earlier post at October 18, 2012 at 12:38 pm.
Fine, at least you know that you were misinformed and won’t repeat the same error again.
BPL 2:57pm => GHE = commonally the so called green house effect. Really is the atm. emissivity effect. Composition of an atmosphere does matter to determine the emissivity e.
Phil.:
Thanks for your post at October 19, 2012 at 4:41 pm.
I love the sight of a troll desperately floundering in the morning. 😉
Richard
I suggest one should look at the greenhouse scorecard to see how the models are doing. I have yet to see one model prediction turn out correct, which is not surprising since they have incomplete data, data that is not accurate ,or comprehensive enough to begin with. Plus the beginning state of the climate can’t be put into the models properly.
The FACT that the hot spot is missing, the stratosphere has not cooled ,along with no decrease in olr , puts the nail in the coffin, for the AGW theory. I say it has been proven wrong.
An upper warmer level of air , will not warm a lower level. Unless you want to change the second law of thermodynamics, which won’t surprise me since the AGW side will do anything to prove there obsolete points.
All those 17 predictions are wrong, look at the data. Again look at the greenhouse scorecard it gives the data versus the model predictions. All of them are flat out wrong.
Example: the stratosphere has NOT cooled,as you claim that is one of the 17 model predictions that is correct.
The atmospheric circulation is becoming more MERIDIONAL with an equatorward shift in the jet stream, not toward the poles. Just look at the ao/nao index since 2008 or so.
There is no sign of any positive feeback between co2 and water vapor (the missing hot spot, it is NOT there,look at rhe data),enso is tending toward more La Ninas, which COOL the tropics. We can go on and on.
The models are completly wrong, and the data confirms this on every single level without exception.
I made a copy of those 17 predictions. Also if you would plot the aa index versus the temperatures you will(over the last 120 years or so) see a much stronger correlation between that index and temp. versus co2 changes and temp. That is a fact. That is what the data shows, I am going by the data.
A Tale of Two Altitudes: how stratospheric temperature is de …
wattsupwiththat.com/…/a-tale-of-two-altitudes-how-stratospheric-tem…
Apr 30, 2012 – The stratosphere has been warming since at least 1995 or so, exactly …. sou
I can back up everything here.
On another note,The outgoing long wave radiation failing to decrease as a result of an increase in co2 is very damming to the AGW argument.
You can’t argue with the data.
Dr. Norman Page, good paper. It shows the temp. has been variable long before the co2 issue came into play. More variable infact then as oppossed to now.
As I had said it is as much about the distribution of temp. changes as it is about the actual decline in temperature, because I think the globe as a whole may cool by.8c by the end of the decade,and latitudes 65n-90n may be the same, while n.h. latitudes 30n-65 n may show a -1.2 c decline in temp., and this is where it matters the most.
The thing is there are thresholds out there , and I don’t know exactly what they are but if solar reaches xxx values for xxx years they will come about.
On the other side this ocean heat content build up late last century is gong to have a lag effect on the temperature decline, but I think as I have said this will become less of a factor as sub-solar activity years accumulate, and if we go into deep solar minimum values once this weak max. of solar cycle 24 passes by.
One thing I am 100% sure of is the temperature rise is over.It is just a matter of how low we go from there and where the effects are felt the most, and how fast or slow it occurs..
Thank You Dr. Page.
Nicola Scafetta, I think we are on the same page as far as solar effects go on the climate, where the difference lies is you think AGW effects are present and I don’t, which gives the different temperature outlook.
That is what it is, as far as I can determine.
Also you are not accounting fro possible thresholds which could come about,(i am not saying they will ,but they could) which would change everything.
Salvatore — Talking about thresholds see http://www.sciencemag.org/content/337/6095/704.figures-only
note especially fig one.
Here is link to abstract
http://www.sciencemag.org/content/337/6095/704.abstract
Here is abstract
Earth’s climate underwent a fundamental change between 1250 and 700 thousand years ago, the mid-Pleistocene transition (MPT), when the dominant periodicity of climate cycles changed from 41 thousand to 100 thousand years in the absence of substantial change in orbital forcing. Over this time, an increase occurred in the amplitude of change of deep-ocean foraminiferal oxygen isotopic ratios, traditionally interpreted as defining the main rhythm of ice ages although containing large effects of changes in deep-ocean temperature. We have separated the effects of decreasing temperature and increasing global ice volume on oxygen isotope ratios. Our results suggest that the MPT was initiated by an abrupt increase in Antarctic ice volume 900 thousand years ago. We see no evidence of a pattern of gradual cooling, but near-freezing temperatures occur at every glacial maximum.
Another great paper relating to solar change.
http://icecap.us/images/uploads/abduss_APR.pdf
Abstract
Temporal changes in the power of the longwave radiation of the system Earth-atmosphere emitted to space
always lag behind changes in the power of absorbed solar radiation due to slow change of its enthalpy. That is
why the debit and credit parts of the average annual energy budget of the terrestrial globe with its air and water
envelope are practically always in an unbalanced state. Average annual balance of the thermal budget of the
system Earth-atmosphere during long time period will reliably determine the course and value of both an energy
excess accumulated by the Earth or the energy deficit in the thermal budget which, with account for data of the
TSI forecast, can define and predict well in advance the direction and amplitude of the forthcoming climate
changes. From early 90s we observe bicentennial decrease in both the TSI and the portion of its energy absorbed
by the Earth. The Earth as a planet will henceforward have negative balance in the energy budget which will
result in the temperature drop in approximately 2014. Due to increase of albedo and decrease of the greenhouse
gases atmospheric concentration the absorbed portion of solar energy and the influence of the greenhouse effect
will additionally decline. The influence of the consecutive chain of feedback effects which can lead to additional
drop of temperature will surpass the influence of the TSI decrease. The onset of the deep bicentennial minimum
of TSI is expected in 2042±11, that of the 19th Little Ice Age in the past 7500 years – in 2055
Dr. Abdossamatov, is also correct. I am thinking 2014 or so.
The question is will any thresholds be met, I mean actual thresholds? I don’t know if I can answer my own question, but I do know they are out there for some given values of solar activity changes,along with earth magnetic field changes. They are out there.
But no two situations will always be the same ,so that different outcomes will be the rule even if various forcings are the same because the climate system is non linear, that is what makes it 1000x harder.
One thing I do know is that the chances of something major have not been this high since the Dalton Minimum.High being relative to years prior to 2005, which presented a zero chance of something major, I say we have a 5% chance now.
I think its more than that – at least 50% go to
http://solarcycle24com.proboards.com/index.cgi?board=general&action=display&thread=855&page=47
and read through the Livingston and Penn thread
You may be correct.
S de P: An upper warmer level of air , will not warm a lower level. Unless you want to change the second law of thermodynamics, which won’t surprise me since the AGW side will do anything to prove there obsolete points.
BPL: Sure it will. There’s no violation of the laws of thermodynamics. What makes you think there is?
Not sure WHO will have his knickers in a twist on this paper, but certainly not Tamino.
This paper by Zhou and Tung is classic case of ‘extreme’ “contamination” in regression analysis.
When you want to remove a known variation in a climate forcing from the global temperature record, you always have to be very careful not to mix cause and effect. After all, if your ‘forcing’ contains a global warming signal, then that too will be eliminated from the global warming record !
In extreme cases, if your ‘forcing’ (cause) mainly consists of the global warming signal itself (effect), then you end up with a flat line. If you subtract a trend line from your forcing, you end up with a trend line. And that is exactly what happened in the case of Zhou and Tung.
The global temperature signal is VERY strong in the AMO index they used :
Check the Northern Atlantic SST record against the global temperature record here :
http://tamino.files.wordpress.com/2011/01/sst_giss.jpg
These two records are clearly highly correlated (anyone want to determine the R^2 on this?).
So, when Zhou and Tung ran their regressions to eliminate their AMO index, they eliminated not just some minor Atlantic SST anomalies, but also most of the global temperature record from the global temperature record. So, they were left over with mostly the trend line in the Northern Atlantic SST record. And remember that that is the trend line was removed BY DEFINITION to obtain their AMO index.
Also it is not as if the trap (of contamination due to mixing up cause and effect) that Zhou and Tung fell right into is new or unknown in the field of climate science.
In fact, there have been dozens of papers pointing out the problems with contamination in multi-regression analysis, and specifically to the AMO, attempt to avoid the problems, and including methods to avoid it date way back :
For example, Mann and Park, 1994 discuss the issue and propose a multivariate signal detection procedures to tease oscillatory patterns apart from long-term (potentially non-linear) trends. Or Schlesinger and Ramankutty, 1994 who use climate model-based estimates of forced trends to estimate a possible residual oscillatory component instead of linear trends.
And then Meehl et al., 2004; Barnett et al., 2005; Hansen et al., 2005 all mention that to properly deal with purely Atlantic variability, it is highly desirable to remove the larger-scale global signal that is associated with global processes, and is thus related to global warming in recent decades, from the AMO.
Also, Trenberth and Shea, 2006 clearly explains the problem of global warming signal being present in the NA SSTs, and suggests a “alternative AMO” definition that at the very least subtracts the global SSTs from the Northern Atlantic SST record (similar to my Tamino’s suggestion to subtract GISS, but probably global SST is better, since it deals with ocean temperatures).
Needless to say that Zhou and Tung’s conclusions that “There is no statistical evidence of a recent slow-down of global warming, nor is there evidence of accelerated warming since the mid-20th century.” as well as “the net anthropogenic trend has been steady at approximately 0.08 °C/decade”, as well as Marcel’s title of this post are incorrect and artificially created by Zhou and Tung defining the AMO as “linearly detrended”.
You are simply looking at the 100 year linear trend line in the global temperature record, which is indeed something like 0.08 C/decade.
Now, if I (as an amateur) can see that there is a problem with this paper in 10 minutes, and an hour to recognize what the problem is, and a couple of hours to find out the background and prior work on this issue, I wonder why was Dr. Tung, with 30 years of experience in this field, not able to do so ?
Oh.And did I forget to mention that Dr. Tung is a student of Dr. Lindzen, and the Chief editor of the journal in which this paper was published ?