From the University of Edinburgh , another one-paper syndrome in the making funded by an NGO research council with a political mission to grab a headline. And, another poorly written press release where they don’t even cite the name of paper. Sigh.
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Climate change has not been strongly influenced by variations in heat from the sun, a new scientific study shows
Climate change has not been strongly influenced by variations in heat from the sun, a new scientific study shows.
The findings overturn a widely held scientific view that lengthy periods of warm and cold weather in the past might have been caused by periodic fluctuations in solar activity.
Research examining the causes of climate change in the northern hemisphere over the past 1000 years has shown that until the year 1800, the key driver of periodic changes in climate was volcanic eruptions. These tend to prevent sunlight reaching the Earth, causing cool, drier weather. Since 1900, greenhouse gases have been the primary cause of climate change.
The findings show that periods of low sun activity should not be expected to have a large impact on temperatures on Earth, and are expected to improve scientists’ understanding and help climate forecasting.
Scientists at the University of Edinburgh carried out the study using records of past temperatures constructed with data from tree rings and other historical sources. They compared this data record with computer-based models of past climate, featuring both significant and minor changes in the sun.
They found that their model of weak changes in the sun gave the best correlation with temperature records, indicating that solar activity has had a minimal impact on temperature in the past millennium.
The study, published in Nature GeoScience, was supported by the Natural Environment Research Council.
Dr Andrew Schurer, of the University of Edinburgh’s School of GeoSciences, said: “Until now, the influence of the sun on past climate has been poorly understood. We hope that our new discoveries will help improve our understanding of how temperatures have changed over the past few centuries, and improve predictions for how they might develop in future. Links between the sun and anomalously cold winters in the UK are still being explored.”
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I’m not so sure this fellow is fully versed on climatology. His papers up to 2011 were all about cosmology, then all of the sudden he starts publishing on climatology issues. One wonders if his previous funding dried up to make such a dramatic shift in study. Then there is: “…climatic fingerprints of high and low solar forcing derived from model simulations…”. IPCC Models haven’t been able to reproduce the last ten years; what makes them think they are worth anything 100-200 years ago?
Here is the abstract: http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2040.html
Small influence of solar variability on climate over the past millennium
- Nature Geoscience (2013) doi:10.1038/ngeo2040
- Received 02 August 2013 Accepted 14 November 2013 Published online 22 December 2013
The climate of the past millennium was marked by substantial decadal and centennial scale variability in the Northern Hemisphere1. Low solar activity has been linked to cooling during the Little Ice Age (AD 1450–1850; ref. 1) and there may have been solar forcing of regional warmth during the Medieval Climate Anomaly2, 3, 4, 5 (AD 950–1250; ref. 1). The amplitude of the associated changes is, however, poorly constrained5, 6, with estimates of solar forcing spanning almost an order of magnitude7, 8, 9. Numerical simulations tentatively indicate that a small amplitude best agrees with available temperature reconstructions10, 11, 12, 13. Here we compare the climatic fingerprints of high and low solar forcing derived from model simulations with an ensemble of surface air temperature reconstructions14 for the past millennium. Our methodology15 also accounts for internal climate variability and other external drivers such as volcanic eruptions, as well as uncertainties in the proxy reconstructions and model output. We find that neither a high magnitude of solar forcing nor a strong climate effect of that forcing agree with the temperature reconstructions. We instead conclude that solar forcing probably had a minor effect on Northern Hemisphere climate over the past 1,000 years, while, volcanic eruptions and changes in greenhouse gas concentrations seem to be the most important influence over this period.
Figure 1: Simulations and temperature reconstructions.
a, Simulations with all forcings (red and green) compared with a reconstruction ensemble14 (blue), and instrumental HadCRUT4 (ref. 24) time series (centred on the average reconstruction over time of overlap, black).
The SI is here: http://www.nature.com/ngeo/journal/vaop/ncurrent/extref/ngeo2040-s1.pdf
h/t to Dr. Leif Svalgaard
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How to damn a study without actually examining it using hard science:
‘I’m not so sure this fellow is fully versed on climatology. His papers up to 2011 were all about cosmology, then all of the sudden he starts publishing on climatology issues.’
I imagine that all those ‘…not fully versed in climatology…’ who regularly do guest posts on WUWT will be quaking in their shoes – particularly comsmologists who are ascribing climate change to cosmic rays. But perhaps you are right after all. Perhaps, if we excluded all those without a strong background in peer-reviewed climatology journals, there would be not nearly as much junk commentary confusing the scientific issues.
‘One wonders if his previous funding dried up to make such a dramatic shift in study.’
Well, ‘wondering’ provides a profound insight into the quality of the science in this study, doesn’t it?
‘Then there is: “…climatic fingerprints of high and low solar forcing derived from model simulations…”. IPCC Models haven’t been able to reproduce the last ten years; what makes them think they are worth anything 100-200 years ago?’
Models are used for every single large-scale and complex human activity – from ship building to space craft, to planning commercial airliner flights, to predicting pork belly futures, to predicting seasonal rainfall and temperatures for crop planning.
climateace says:
December 23, 2013 at 3:18 pm
Models are used for every single large-scale and complex human activity – from ship building to space craft, to planning commercial airliner flights, to predicting pork belly futures, to predicting seasonal rainfall and temperatures for crop planning.
____________________________
To claim that climate models are as accurate as mechanical engineering models would be dishonest, because it isn’t true. To allude to similar accuracies in order to give the impression of equivalence of the models also falls under the heading of questionable veracity.
For those who believe humans produced CO2 in the Earth’s atmosphere (an increase of 0.005% over the course of 150 years) has a greater effect on the temperature of our planet than changes in the output of the sun:
http://www.rayfowler.org/blog/wp-content/uploads/size_of_earth_3.jpg
Donald Mitchell says: @ur momisugly December 23, 2013 at 2:52 pm
I think that the disclaimer is in the main claim:
“Climate change has not been strongly influenced by variations in heat from the sun”….
>>>>>>>>>>>>>>>
Nice catch.
No only is there the solar magnetic field/cosmic ray possible link, there is also the fact that although TSI may not vary the composition of the TSI does vary especially in the UV and EUV wavelengths and that effect ozone formation/destruction and the “puffyness’ of the atmosphere.
NASA: Solar Variability and Terrestrial Climate
http://solar.physics.montana.edu/SVECSE2008/pdf/floyd_svecse.pdf
Long-Term Variations in UV and EUV Solar Spectral Irradiance, Slide #4
I think you’re right Anthony about the authors inexperience with climatology. It’s well known within the climate science community that anthropological greenhouse gas quantities are mostly irrelevant before about mid 20th century. When the author suggests that 1800 is the starting point, which coincides with the start of the industrial revolution, it shows that this is not a scientific paper, but rather a political essay.
I’ve seen this mentioned a couple of times but it’s a misleading figure, It does not the earth is receiving 1.5 w/m2 less energy 24/7. Averaged over the whole surface, the earth receives about 240 w/m2. A reduction of 1.5 w/m2 in TSI would translate into an average decrease of just 0.26 w/m2 and a temperature decline of less than 0.1 k.
William Astley says:
December 23, 2013 at 3:10 pm
TSI has dropped roughly 1.5 watts/meter^2. It is odd that there is no discussion of that fact in the media.
Because it didn’t happen.
In the last 70 years, the solar magnetic cycle was at its highest and longest period of high activity in the last 6000 years
And this is also not correct.
The supposedly huge volcanic activity of the LIA should be pretty easy to track to each individual volcano and its location, type of eruption… or would that be too much for those climatowriters?
” Models are used for every single large-scale and complex human activity – from ship building to space craft, to planning commercial airliner flights, to predicting pork belly futures, to predicting seasonal rainfall and temperatures for crop planning.”
– – –
There are a number of different kinds of computer models. Some models consist of algorithms that manipulate data structures. They sort, graph, schedule… They do what humans can do, but much faster. These are not climate models.
Computer models of the mathematical continuum fall under two categories. Those that discretize the math under consideration for numerical analysis (this is the kind Mosher likes to reference). These types are not climate models.
The second category does no use a mathematical model directly, because one does not exist. It is an amalgamation of the other types, a pseudo model of the real world. There doesn’t yet exist a mathematical equation for earths climate, and there isn’t sufficient computer resources yet to faithfully reproduce the earths climate for sufficient periods of time to be useful. The subset, weather models, are only good for up to about 7 to 8 days.
Some of your examples actually confirm what the skeptics have to say about models. What is the range of error for example in planning commercial flights?
There are many things within the human domain that have not yet been modeled sufficiently for predictive purposes. The predictions from Environment Canada for the next quarter temperatures has been shown to be worse than random guess for example.
Thank you Nic Lewis for your frequent, knowledgeable comments.
In reply to:
John Finn says: December 23, 2013 at 4:53 pm William Astley says:
December 23, 2013 at 3:10 pm
TSI has dropped roughly 1.5 watts/meter^2. It is odd that there is no discussion of that fact in the media.
Flinn: I’ve seen this mentioned a couple of times but it’s a misleading figure, It does not the earth is receiving 1.5 w/m2 less energy 24/7. Averaged over the whole surface, the earth receives about 240 w/m2. A reduction of 1.5 w/m2 in TSI would translate into an average decrease of just 0.26 w/m2 and a temperature decline of less than 0.1 k.
William: You miss the point. The abrupt reduction in TSI supports the assertion that solar magnetic cycle 24 is an abrupt change to the solar magnetic cycle. The sudden reduction of TSI of 1.5 watts/meter^2 or 0.26 watts/meter^2 averaged over night and daytime and making allowance for a sphere is significant.
The massive increase in GCR is also an abrupt change. http://www.woodfortrees.org/plot/pmod/from:1971
GCR at solar magnetic cycle 24 maximum is as high as past cycle averages. http://cosmicrays.oulu.fi/
The highest multiple month sea ice around Antarctic in 40 years is an abrupt change.
http://nsidc.org/data/seaice_index/images/daily_images/S_stddev_timeseries.png
The largest increase in Arctic sea ice in record is an abrupt change.
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png
Abrupt changes require a physical explanation. The planet was started to cool, the reason for the sudden cooling is the solar magnetic cycle 24 change. The gig is up.
I read as far as this;
“Climate change has not been strongly influenced by variations in heat from the sun, a new scientific study shows.”
…and promptly started reading the comments.
Peter Miller says:
No…You are presumably using solar irradiance data that is measured in terms of W/m^2. That is per m^2 where the Earth intercepts an amount equal to pi*R^2. The W/m^2 forcing that CO2 causes is per m^2 of the Earth’s surface, which has 4*pi*R^2 of surface area. Hence, you have to divide the change in solar irradiance by 4 to get the amount per m^2 of the Earth’s surface.
Furthermore, not all of the incident radiation from the sun is absorbed by the Earth…About 30% gets reflected…So, you have to then multiply by a factor of 0.7. So, in fact, the forcing from the solar cycle is a lot smaller. It is also worth noting that its effect is further reduced by thermal inertia effects…I.e., the 11-year cycle is fast enough that the Earth is not able to equilibrate with the current solar forcing and this causes a further dampening of the solar effect. (You see this even more dramatically for the diurnal cycle: After all, on a local scale, the solar irradiance goes to zero every night but the temperatures don’t plummet accordingly. Part of this is attributable to the transport of heat around the surface but a lot (probably most) is due to thermal inertia effects.
[I now see that John Finn has recently made essentially the same point as I.]
A couple of posters have responded to my comment on models.They made points about models and general and some models in particular. These points may, or may not, be reasonable.
But these comments miss my point: if you want to diss a particular model, for whatever set of reasons, you have to diss the model being questioned… not some other model(s).
The next step along this slippery slope – dissing all models simply because they are models – is simply unsustainable. Our civilization would grind to a very rapid and messy halt without the constant application of myriad models.
“Here we compare the climatic fingerprints of high and low solar forcing derived from model simulations with an ensemble of surface air temperature reconstructions14 for the past millennium.”
Meanwhile, back in the real world …..
Nic Lewis says:
December 23, 2013 at 2:46 pm
1. Nicola Scafetta wrote:
“If hockey-stick like temperature reconstructions are used, then the solar signature is very small.”
I’m not sure that applies here – their detection and attribution analysis, according to Tables S2 and S3, was based on regressions over 1000-1900 and 1450-1900, before the blade of the hockey stick takes off.
*********************
No, Nic, That is irrelevant.
The hockey-stick like temperature reconstructions claim that the temperature before 1900 varied very little, about 0.2-0.3 C. If the temperature varied so little from the MWP and the LIA then solar changes could only effect climate little, by 0.1-0.2 C, the vocanos get another ~0.1-0.2 C. This is independent of what happens after 1900.
The new temperature reconstructions present a much larger preindustrial variability from MWP to LIA (0.6 C and above). In this situation the solar effects must be increased to about 0.5 C (and above), while the volcano cannot be increased because the volcano cooling spikes provide an upper limit.
Read my recent papers, for example.
Scafetta N., 2013. Discussion on common errors in analyzing sea level accelerations, solar trends and global warming. Pattern Recognition in Physics, 1, 37–57. (open access)
http://www.pattern-recogn-phys.net/1/37/2013/prp-1-37-2013.html
Scafetta, N. 2013. Discussion on climate oscillations: CMIP5 general circulation models versus a semi-empirical harmonic model based on astronomical cycles. Earth-Science Reviews 126, 321-357.
http://www.sciencedirect.com/science/article/pii/S0012825213001402
@climateace
“The next step along this slippery slope – dissing all models simply because they are models – is simply unsustainable. Our civilization would grind to a very rapid and messy halt without the constant application of myriad models.”
Problem is that all models are merely the figment of the modeler’s imagination (or his/her very limited understanding of stuff).
The Sun is currently in its lowest solar cycle since 1906 and it peaked this year, so it only weakens from here.
Over the past 20 years, solar activity has been falling at its fastest pace in 10,000 years, which seems to explain the lack of a warming trend since November 1996. Combine this with the collapsing Umbral Magnetic Field, an excellent case can be made that the next solar cycle will be even lower than the current one, and could well be the lowest since the end of the Maunder Minimum in 1715.
If global temps continue to decline (HADCRUT4= -0.02C/decade since 2001), while record yearly amounts of CO2 emissions are observed, the CAGW hypothesis cannot survive the validation parameters of the Scientific Method.
It just seems a matter of time before CAGW won’t pass the giggle test and is finally thrown on the trash heap of failed ideas.
In reply to:
William:
Yes it is.
[Check the nested blockquotes: You’re quoting lsvalgaard quoting you, right? Twice, right? Mod]
climateace says:
December 23, 2013 at 5:59 pm
But these comments miss my point: if you want to diss a particular model, for whatever set of reasons, you have to diss the model being questioned… not some other model(s).
The next step along this slippery slope – dissing all models simply because they are models – is simply unsustainable.
_________
I only diss models that have been, without fail, complete and utter failures for over twenty years — which means I only diss climate models.
Imagine if jets were crashing every time they took off for twenty years and running, and the aeronautical engineers defended their models by looking for “the missing lift”.
It’s laughable and beyond defense.
Your straw man argument is as weak as the models you defend.
‘Research examining the causes of climate change in the northern hemisphere over the past 1000 years has shown that until the year 1800, the key driver of periodic changes in climate was volcanic eruptions.’
http://www.longrangeweather.com/global_temperatures.htm
Then this graph is all wrong. It show volcanic eruption as the climate climbed out of the little ice age not too much activity coming out of the MWP.
Another recent paper worth debunking was reported by the Guardian and Wired UK:
Billion-dollar climate denial network exposed: http://www.wired.co.uk/news/archive/2013-12/21/denial
Author Robert Brulle teaches Critical Theory, related to Marxism and Postmodernism. Basically an social pseudo-science activist.
climateace says:
December 23, 2013 at 5:59 pm
A couple of posters have responded to my comment on models.They made points about models and general and some models in particular. These points may, or may not, be reasonable.
But these comments miss my point: if you want to diss a particular model, for whatever set of reasons, you have to diss the model being questioned… not some other model(s).
The next step along this slippery slope – dissing all models simply because they are models – is simply unsustainable. Our civilization would grind to a very rapid and messy halt without the constant application of myriad models.
———————-
Climateace,
Nobody disses all models simply because they are models. This is known as a ‘knocking down a strawman’. I personally lump climate models together in general because the IPCC is fond of using ensembles of climate models, apparently to poor effect in projecting future temperatures.
It has been suggested many times, at least some of which I believe I’ve seen in the comments here on WUWT (although I may be mistaken and have no intention of digging around to verify) that perhaps it would make more sense to exert some effort to separate the ‘better’ models from the ‘poorer’ ones (skipping a lot of interesting detail), although it still doesn’t seem to have occurred to the IPCC that it would be beneficial to do so.
In short, perhaps your time would be better spent heckling them about how all models are not equal.
Merry Christmas, in case we don’t speak again. If I can be of any further assistance, please don’t hesitate to ask.
climateace says:
December 23, 2013 at 5:59 pm
…The next step along this slippery slope – dissing all models simply because they are models – is simply unsustainable. Our civilization would grind to a very rapid and messy halt without the constant application of myriad models.
>>>>>>>>>>>>>>>>>>>>>.
Models are only as good as the data and formula used to build them and they are completely worthless if they are not validated by actual real life experimental data.
As a chemist in manufacturing I have generated that experimental data to validate the computer models I helped designed.
We tossed out a heck of a lot of models because experimental data showed they were complete garbage. This is the critical step missing in IPCC climate science. The last assessment report show the climate models need to be tossed on the scrap heap but that is not what is happening. Instead they get renamed ‘projections’ and used to determine the economic policies of whole countries.