Scientists find errors in hypothesis linking solar flares to global temperature
From Physorg.com. h/t to Leif Svalgaard who offers this PDF with this diagram that makes it all clear.
In contrast to a previous analysis, a new study has shown that the distributions of (a) the global temperature anomaly by month since 1880 and (b) the solar flare index by day over a few solar cycles are fundamentally different. One feature the detrended data do have in common is self-similarity: the probability density functions are the same on different time scales, which means that neither can be described as Lévy walks. Image credit: Rypdal and Rypdal.
(PhysOrg.com) — The field of climate science is nothing if not complex, where a host of variables interact with each other in intricate ways to produce various changes. Just like any other area of science, climate science is far from being fully understood. As an example, a new study has discredited a previous hypothesis suggesting the existence of a link between solar flares and changes in the earth’s global temperature. The new study points out a few errors in the previous analysis, and concludes that the solar and climate records have very different properties that do not support the hypothesis of a sun-climate complexity linking.
In a handful of studies published in Physical Review Letters between 2003 and 2008, a team from Duke University and the Army Research Office including Nicola Scafetta and Bruce West analyzed data that appeared to show that solar flares have a significant influence on global temperature. Solar flares, which are large explosions in the sun’s atmosphere that are powered by magnetic energy, vary in time from a few per month to several per day. Although solar flares occur near sunspots, their frequency variation occurs on a much shorter time scale than the 11-year sunspot cycle. In their studies, the researchers’ results seemed to show that data from solar flare activity correlates with changes in the global temperature on a short time scale. Specifically, their analysis showed that the two time records can both be characterized by the same Lévy walk process.
However, in the new study, which is also published in Physical Review Letters, Martin Rypdal and Kristoffer Rypdal of the University of Tromso in Norway have reexamined the data and the previous analysis and noticed some shortcomings. One of the biggest causes of concern is that the previous analysis did not account for larger trends in factors that affect solar flares and global temperature. For instance, the solar cycle has its 11-year periodic trend, where periods of lots of sunspots cause larger numbers of solar flares. Likewise, the global temperature anomaly has numerous other factors (a “multi-decadal, polynomial trend”) that impacts global temperature fluctuations. By not detrending this data, the analysis resulted in abnormally high values of certain variables that pointed to Lévy walk processes. By estimating the untrended data, Rypdal and Rypdal hypothesized that the solar flare records might be described by a Lévy flight, while the global temperature anomaly might obey a distribution called persistent fractional Brownian motion.
Read the entire article here at Physorg.com
A preprint of the paper is available here
Practice making your own Levy walks here
I cannot understand why anybody talks about TSI at all, when what is found to be correlated with climate / temperature is various aspects of the entire double cycle, particularly cycle length and magnetic variation.
To use TSI as a proxy for anything interesting is just silly, and the concentration of this paper “solar flares” smacks very heavily of a strawman.
Don B (11:49:45) :
Wolf, Sporer and Maunder were all “stronger” minima, and associated with LIA.
Who makes the ‘association’? And the correspondence is not so good. The Wolf minimum was deep and broad, yet temperatures then were as today: http://www.leif.org/research/Loehle-Temps-and-TSI.png
Same with the unnamed minimum around 600 AD. Bottom line: there is no good evidence for any connection.
Its volcanoes, volcanoes, volcanoes and… location, location, location.
Leif: Agreed on the Iguato river. I’m going to see if I can find out who that guy is and if he ever published and why that hit him on the head like you did me with it. The sun is bloody annoying actually now that I think about it! A sort of Enigma in front of your face! Sending us off down blind alleys with spots and flares and non-barrycenters or not, cycles, etc. Even Oliver thinks it’s a neutron bomb encassed in a Iron core!
Leif Svalgaard (12:12:06) :
BTW in http://www.leif.org/research/Loehle-Temps-and-TSI.png the two bottom graphs show different estimates of solar activity, derived from different cores by different teams and methods. Note that they agree rather well, but not with the temperature reconstruction. Now, you can always claim that the only good temperature reconstructions are the ones that agree. There are people who do that, you are welcome to join their ranks 🙂
I feel like i’ve been rock face climbing for two years and I look down and i’m about 3 feet off the ground!!! : (
Oops, its also a lack of volcanoes sometimes too… and their locations.
Dr. Svalgaard presents Evans (11:08:41) statement: “While it’s admirable that the scientists are so up-front with their goals and purposes”.
And Dr. Svalgaard (11:35:21) responds: “I think you miss the point. Their statement is not about goal and purpose, but about proper scientific analysis…”
I accept your point that part of the statement goes to proper scientific analysis…which is as you say, “to seperate the wheat from the chaff” and focus on one individual hypothesis at a time.
But I think it’s also fair to say the authors of the paper have an “outcome” oriented agenda, as evinced by this statement: “This has been the strategy of Scafetta and West over the years, and we have no illusion that our paper will put them to silence.”
It would seem that Martin Rypdal, an author of the posted paper, attributes motive to Scafetta and West, but is blind to the motive his statement reveals, “put them to silence”, or maybe Rypdal doesn’t care about whether people knows his agenda — in fact, it would seem from such a statement in the Phys.org article that, in fact, he does want people to know his agenda.
And, as stated above, knowing Rypdal’s agenda should make readers cautious when assessing the his work.
Craig Goodrich (12:09:38) :
To use TSI as a proxy for anything interesting is just silly, and the concentration of this paper “solar flares” smacks very heavily of a strawman.
TSI is a very good proxy for solar activity in itself as it is modulated by magnetic activity. The cycle length etc is just voodoo and has no credence. BTW, the ‘TSI’ I referred to is actually derived from magnetic activity, namely cosmic ray modulation by the Sun’s magnetic field.
johnythelowery (12:15:36) :
Even Oliver thinks it’s a neutron bomb encassed in a Iron core!
Oliver is a special case. Few ascend to his heights. 🙂
steven mosher (11:21:57) :
for those of you commenting on the “brownian motion” aspect, you
need to realize that they detrended the data with a 4th order poly
that represented the decadal variations ( read oceanic cycles) in the
data. S&W missed this step and its fairly well known that to estimate
H ( Hurst ) you need to take care, as these authors did.
Random walks can happen it random environments, with random potentials, this has been rigorously proved eg Yasha Sinai 1982.
That there is no prohibition to random excursions that my happen from time to time is also a legitimate line of enquiry.
The Ruelle conjecture is that random excursions can exhibit historical behaviour without being recurrent is a constraint on the degree of certainty that can be applied to modelling complex systems where the qualities are not known and only a statistical description is available.
The Almighty Chance is a troublesome property.
http://www.worldscibooks.com/physics/0862.html
Referencing the concluding paragraph:
“The theory of anthropogenic global warming consists of a set of logically interconnected and consistent hypotheses,” Martin Rypdal said. “This means that if a cornerstone hypothesis is proven to be false, the entire theory fails. A corresponding theory of global warming of solar origin does not exist. What does exist is a set of disconnected, mutually inconsistent, ad hoc hypotheses. If one of these is proven to be false, the typical proponent of solar warming will pull another ad hoc hypothesis out of the hat. This has been the strategy of Scafetta and West over the years, and we have no illusion that our paper will put them to silence. However, the only scientifically valid strategy to confront these new hypotheses is to shoot down every new missile as they come in, using the most advanced weapons at hand.”
The idea that one should try and shoot down a new hypothesis is, of course, a vital process for the advancement of science. To assume beforehand that all hypothesis regarding the sun and climate change will be shot down is, of course, a bias, and is a clear statement of an agenda.
The question then arises: Why is there no consorted effort to ‘shoot down’ the notion of positive feedbacks to increasing CO2, the ultimate cornerstone to the AGW theory? On the contrary, there has been a large, expensive and consorted effort to FIND evidence of the persistent positive feedbacks, with little success, yet no one is ever applauded for ‘shooting down’ the feedback cornerstone! It is quite obvious that the AGW theory is treated as sacrosanct by a large segment of the atmospheric science community, which explains why so little has been accomplished in the field over the last 20 years.
The diagram looks like Brownian motion as generated, of course, by a nice hot cup of tea, much like the Infinity Improbability Drive from The Hitchhiker’s Guide to the Galaxy. (h/t the late Douglas Adams)
Paul 🙂
Leif: Okay. Agree about my daft River stuff. But, let’s hear Pablo Mauas out…
PABLO MAUAS and RIVER FLOW CORRELATIONS WITH SUN ACNE
‘……………………..
Flowrate of World’s 4th Largest River Linked to Solar Cycle
Monday, 05 April 2010 22:11 Dr. David Whitehouse .A new study has postulated a link between solar activity and the flowrate of one of the largest rivers in the world, and suggests that it will lose water as the current low solar activity continues.
The quantity of water flowing down a river is a good climatic indicator since it integrates rainfall over large areas. In a paper submitted to the Journal of Atmospheric and Solar-Terrestrial Physics, Pablo Mauas and Andrea Buccino of the Institute of Astrophysics, and Eduardo Flamenco of the National Institute of Agricultural Technology, Argentina, follow-up a previous study of the influence of solar activity on the flow of the Paraná River – the fourth largest river in the world by outflow – and second only to the Amazon in South America.
They find that the unusual minimum of solar activity observed in recent years has a correlation with very low water levels seen in the Paraná’s flowrate. Additionally they report historical evidence of low water levels during the Little Ice Age.
They also consider flowrates for three other rivers (Colorado, San Juan and Atuel), as well as snow levels in the Andes. They conclude, after eliminating secular trends and smoothing out the solar cycle, there is a strong positive correlation between the residuals of both the Sunspot Number and the flowrates of these rivers as well.
Looking more closely at the data they say that the correlation between Sunspot Number and low water flow rates is stronger than that between flow rates and the incidence of Galacric Cosmic Rays suggesting that the chief influence on climate here is probably changes in solar irradiance and not changes in cosmic rays affecting levels of cloudiness over the region studied.
Both results imply that higher solar activity corresponds to more intense precipitation, in summer and in winter, in the large river basins of South America that have been studied.
The correlation between sunspot number and the rivers’ behavior has been tracked over more than one solar cycle suggests to the researchers that the low levels of activity expected for Solar Cycle 24 will result in a dry period for the river Parana in particular over the next decade.
Usually studies that investigate the effect of solar activity levels on climate have been carried out in the northern hemisphere and have been limited to studying Northern Hemisphere temperatures or sea surface temperatures. In recent years however some correlation has been postulated between solar activity and the Asian monsoon. This study is among the first to link the sun’s prolonged solar minimum at the end of cycle 23 to decadal variations in the weather.
Feedback: david.whitehouse@thegwpf.org This e-mail address is being protected from spambots. You need JavaScript enabled to view it
…………………………………………………………………………………………………’
Leif Svalgaard (10:07:02) :
John F. Hultquist (09:51:42) :
This seems to be false logic of the “it does not follow” type (non sequitur).
If we are not distracted by that nonsense [likely injected by the journalist] the paper by R&R ends much more reasonably: “The results provide strong evidence that the stochastic properties of the temperature record are generated by the long-term memory internal dynamics of the climate system and are not linked to the short-memory intermittent fluctuations which characterize the solar output”.
I thought that there are several solar cycles over and above the 11/22 year sunspot cycles. Are there and how do they fit in with this theory.
For those asking about Levy Flights and fractals.
Persistent brownian motion is just a random walk in which the size of each step is described by a gaussian (normal) distribution.
A Levy flight (a motion often found in such things as the flight of an Albatross and animal foraging behavior) is just a random walk in which the size of each step is described by a power-law distribution (i.e. many small steps, fewer and fewer long steps).
That is, brownian motion has a definable scale (defined by the mean of that normal distribution), whereas a Levy flight does not (and is therefore a type of fractal).
James F. Evans (12:21:25) :
It would seem that Martin Rypdal, an author of the posted paper, attributes motive to Scafetta and West, but is blind to the motive his statement reveals, “put them to silence”
It is S&W that have an agenda, putting an agenda to silence is what climate skeptics are trying to do, no?
And, as stated above, knowing Rypdal’s agenda should make readers cautious when assessing the his work.
This applies only to people that do not understand the paper or the issue. If I claim that 2+2=5 because my agenda says that modern science is all wrong and is one big conspiracy against the good people who only believe in observation and measurement [e.g. what they can see with their own lying eyes] and all the rest is theory and assumptions built on mathematical models [using the false assertion that 2+2=4] who no-one understands, then that claim can be refuted regardless of what my agenda is.
Does this make sense?
The polar regions do not get much direct heating from solar radiation, far less than the tropical regions. Thus if you were trying to match up “pulses” from the Sun with temperatures, you certainly would not want to use the GTA which smears together all the regions. You should concentrate on tropical temperatures, as there you would find the strongest signal of heating influenced by solar variances.
Does that sound reasonable? Has anyone tried it?
Leif Svalgaard (11:14:37) :
“”Hmm, I wasn’t appealing to ignorance to dispute the paper, but instead asking a question. ”
I was not referring specifically to ignorance on your part, but to the general fallacy behind “what else can it be?”. just because we don’t know another explanation, does not make the one we have correct.”
But that is the summation of the entire IPCC argument for accepting the AGW theory and making life more difficult for every man, woman and child on the planet. “Our models don’t work if we do not include greenhouse gases as the main driver of late 20th century warming, so CO2 must be the reason!” Why is the IPCC argument not immediately recognized as a fallacy by all reasoning people?
(I remember almost falling off my chair when I first read it in the Executive Summary, then sat dumbfounded for months as the mainstream scientific community nodded in unison as if the argument was iron clad!)
That Levy walk resembles the route I take home when returning from the pub on a Saturday evening.
Somewhat OT, but given the recent interest in stats, and Bayes in particular, I thought this was interesting as an example of a practical application of Bayes Theorem. These kinds of things are common in many applications, including the “Help” function in MS Office. It also illustrates a weakness – so draw whatever conclusions you’d like from that. 🙂
To me it illustrates the danger of not taking proper care in selecting a statistical/probability approach for the task, and ignoring the logic/common sense required to address adequately the issue. I think far too many people are very mechanical in their approach to the use of statistical analysis, when they should not be. Statistics merely inform our opinion and actions, they should never decide.
From: Risks Digest – http://catless.ncl.ac.uk/Risks/26.01.html#subj22
The next escalation in the spam war: circumventing Bayesian filters
Jonathan Kamens
Thu, 01 Apr 2010 01:58:51 -0400
I’ve been using bogofilter , a Bayesian
spam filter, to filter
email coming into my inbox for over seven years; I even wrote and maintain
the Milter that integrates bogofilter with
sendmail . Until quite recently, it has
been remarkably effective. For example, in the past year, an average of 935
spam messages per day have passed through my bogofilter, and it successfully
identified over 98% of them as spam, with very, very few false positives.
All that changed on 10 Mar. Since then, the success rate of bogofilter has
plummeted from over 98% to less than 85%. In real terms, this means I’m
being forced to at least briefly eyeball well over 100 spam messages per day
to confirm that they’re spam so I can tell bogofilter to retrain them,
whereas before I was seeing less than 20. Yowza! (You can see a 60-day
history of my bogofilter stats showing this dramatic drop on my home page
.)
The cause of the success rate plunge appears to messages such as this one
, each of which
contains, below the actual spam payload, a sequence of random text snippets
on many different topics.
These messages are coming from many different IP addresses, so it would seem
that they’re being generated by a botnet.
I did a quick statistical analysis of a small subset of these messages that
I’ve received, 35 of them, and discovered that these 35 messages contained
10,860 unique words, of which over 68% appeared in only one of the messages,
81% appeared in one or two messages, 87% appeared in 1-3 messages, 90%
appeared in 1-4 messages, and 98% appeared in less than half of the
messages. This would seem to indicate that the text snippets being used by
the spam generator vary widely and are thus likely to hit upon keywords that
previously occurred in legitimate email.
It would seem that somebody has figured out how to do a pretty good job of
outsmarting Bayesian filters. Frankly, I’m rather surprised that it’s taken
this long.
I’ve started a discussion about this on the bogofilter mailing list, which
those of you who are curious can follow at
http://thread.gmane.org/gmane.mail.bogofilter.general/11492.
Quoting from Rypdal & Rypdal’s preprint” “….These results provide strong evidence that the stochastic properties of the temperature record are governed by the long-memory internal dynamics of the climate system and are not linked to the short-memory intermittent fluctuations which characterize the the solar output.” One is hard pressed to understand where L. Zyga came up with his or her conclusions. I suggest they be ignored. I see no problem with the math and must accept R&R’s work, until someone more qualified can show it to be in error. I do have many of the same concerns, already stated by others in this thread. I am not comfortable with any attempt to extrapolate their conclusions further then the authors have stated in their paper.
Sorry if this is OT. I know other people have implied this, my apologies for not giving proper reference credit but I think we might have the beginning of a counter hypothesis to CO2 based AGW – or significant AGW in general – to explain the temperature increases for last 30 years. In particular this hits off some of the mechanisms described in Wilde’s (I think it was Wilde) in the recent post on a new model for climate a few days back.
In summary, we know that insolation levels do not seem to correlate well (if at all) with global temps… but we know that virtually all energy (with the exception of energy coming from the earth’s core) comes from the sun. We know, as is well demonstrated by every El Nino, that the oceans can have massive impacts on global temps. After all, they store 1000x more energy than the atmsphere. Note as well recent work on the faint sun paradox which does not show the “expected” CO2 levels – which leaves the oceans, water vapor and clouds to explain (anything else I’m missing)?
If insolation did match temps we would see measurable fluctuations every 11-or-so years, and on longer cycles, that correlate with solar input. If CO2 and atmospheric water vapor were the cause (as implied by Hansen and the “consensus”) then we should have seen continued increases in temp over the last few years which we haven’t.
This could be the big chicken and the egg. Currently the thinking seems to be that the atmosphere drives OHC… but the oceans have shown us (through El Nino) that they can collect and expell energy quite effectively on somewhat random timeframes. To quote Henry chance (I think that’s the poster’s name) from a recent discussion, perhaps atmospheric temps are really a “lagging indicator” of changes in solar input via the ocean?
Don’t get me wrong, clouds are hugely important in controlling input into the system, UHI/LULC is important to understanding the behavior of the other 29-or-so-% of the earth’s surface, and Greenhouse Effect is important to keeping us insulated from outer space… but the idea that GHG control it all seems somewhat backwards. In particular, the notion that CO2 drove atmspheric water increase, and that between them they drove all the temperature increases measured since 1980 seems patently ridiculous. How can the portion of the system (atmosphere) that contains 1/1000 of another (oceans) – note: that’s without even including net energy stored in the land surface – control all of it?
Dr. Svalgaard
Where am I wrong here?
bubbagyro (12:04:37) wrote: “As to the shooting of missiles as they appear, this is the ABSOLUTE goal of science. Mr. Evans may not be a scientist, but our goal as scientists is to attack (nullify) every new hypothesis. Withstanding such attacks over time leads to theory. We expect our own hypotheses to be nullified; this we not ony deserve, but expect and embrace.”
Yes, I’ll stand corrected.
Perhaps, also, the goal should be to not assume prior theories are infalable and be open to challenges to those older theories. Sometimes, it seems such is not the case.
So, it depends on the quality and quantity of data, observations & measurements, methodology, and analysis & interpretation.
Close scrutiny with reasonable skepticism and an open-mind should be applied to all scientific papers.
Sometimes there is a thin line between proper scientific falsification and personal agendas.
johnythelowery (12:43:13) :
that the chief influence on climate here is probably changes in solar irradiance and not changes in cosmic rays affecting levels of cloudiness
go tell that to the Svensmark enthusiasts. This precisely illustrates the point, that the new hypotheses [actually an old one, the Nile is also rumored to follow the sun, e.g. in this marvelous piece: http://www.cyclesresearchinstitute.org/astronomy/arnold_theory_order.pdf ] are disconnected to some older ones and the whole thing is a mess.
SandyInDerby (12:45:30) :
I thought that there are several solar cycles over and above the 11/22 year sunspot cycles. Are there and how do they fit in with this
There seems to be a ~100 year cycle, but it is not clear if this is a REAL cycle or just coincidence or some natural slow variation of solar parameters.