There is a new paper in Environmental Research Letters that give additional support to Henrik Svensmark’s cosmic ray hypothesis of climate change on Earth. The idea is basically this: the suns changing magnetic field has an influence on galactic cosmic rays, with a stronger magnetic field deflecting more cosmic rays and a weaker one allowing more into the solar system. The cosmic rays affect cloud formation on Earth by creating condensation nuclei. Here is a simplified block flowchart diagram of the process:
The authors of the the new paper have a similar but more detailed flowchart:
The new paper suggest that changes in the quantity of cloud condensation nuclei (CCN) are caused by changes in the cosmic ray flux:
The impact of solar variations on particle formation and cloud condensation nuclei (CCN), a critical step for one of the possible solar indirect climate forcing pathways, is studied here with a global aerosol model optimized for simulating detailed particle formation and growth processes. The effect of temperature change in enhancing the solar cycle CCN signal is investigated for the first time. Our global simulations indicate that a decrease in ionization rate associated with galactic cosmic ray flux change from solar minimum to solar maximum reduces annual mean nucleation rates, number concentration of condensation nuclei larger than 10 nm (CN10), and number concentrations of CCN at water supersaturation ratio of 0.8% (CCN0.8) and 0.2% (CCN0.2) in the lower troposphere by 6.8%, 1.36%, 0.74%, and 0.43%, respectively. The inclusion of 0.2C temperature increase enhances the CCN solar cycle signals by around 50%. The annual mean solar cycle CCN signals have large spatial and seasonal variations: (1) stronger in the lower troposphere where warm clouds are formed, (2) about 50% larger in the northern hemisphere than in the southern hemisphere, and (3) about a factor of two larger during the corresponding hemispheric summer seasons. The effect of solar cycle perturbation on CCN0.2 based on present study is generally higher than those reported in several previous studies, up to around one order of magnitude.
The wider variation in CCNs makes the Svenmark’s hypothesis more plausible since the effect on clouds would also be proportionately larger.
They conclude:
The measured 0.1% level of the longterm TSI variations on Earth’s climate (i.e., solar direct climatic effect) is too small to account for the apparent correlation between observed historical solar variations and climate changes, and several mechanisms amplifying the solar variation impacts have been proposed in the literature.
Here we seek to assess how much solar variation may affect CCN abundance through the impacts of GCR and temperature changes on new particle formation, using a global aerosol model (GEOSChem/APM) optimized for simulating detailed particle formation and growth processes. Based on the GEOSChem/ APM simulations, a decrease in ionization rate associated with GCR flux change from solar minimum to solar maximum reduces global mean nucleation rates CN3, CN10, CCN0.8, CCN0.4, and CCN0.2 in the lower troposphere (0–3 km) by 6.8%, 1.91%, 1.36%, 0.74%, 0.54%, and 0.43%, respectively. The inclusion of the impact of 0.2 C temperature increase enhances the CCN solar cycle signals by around 50%.
The annual mean solar cycle CCN signals have large spatial and seasonal variations, about 50% larger than in the northern hemisphere than in the southern hemisphere and about a factor of two larger during the corresponding summer seasons. The average solar cycle signals are stronger in the lower troposphere where warm clouds are formed. The regions and seasons of stronger solar signals are associated with the higher concentrations of precursor gases which increase the growth rate of nucleated particles and the probability of these nucleated particles to become CCN. The effect of solar cycle perturbation on CCN0.2 based on the present study is generally higher than those reported in several previous studies, up to one order of magnitude. Clouds play a key role in the energy budget of Earth’s surface and lower atmosphere.
Small modifications of the amount, distribution, or radiative properties of clouds can have significant impacts on the climate. To study the impacts of a 0.5%–1% change in CCN during a solar cycle on cloud albedo, precipitation, cloud lifetime, and cloud cover, a global climate model considering robust aerosol–cloud interaction processes is needed. It should be noted that 0.5%–1% change in CCN during a solar cycle shown here only considers the effect of ionization rate and temperature change on new particle formation. During a solar cycle, changes of other parameters such as UV and TSI flux may also impact chemistry and microphysics, which may influence the magnitude of the solar indirect forcing. Further research is needed to better quantify the impact of solar activities on Earth’s climate.
Note the bold in the last paragraph.
WUWT readers may recall that Dr. Roy Spencer pointed out the issue of a slight change in cloud cover in his 2010 book intro of The Great Global Warming Blunder: How Mother Nature Fooled the World’s Top Climate Scientists. He writes:
“The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.”
The paper at ERL:
Effect of solar variations on particle formation and cloud condensation nuclei
Fangqun Yu and Gan Luo
The impact of solar variations on particle formation and cloud condensation nuclei (CCN), a critical step for one of the possible solar indirect climate forcing pathways, is studied here with a global aerosol model optimized for simulating detailed particle formation and growth processes. The effect of temperature change in enhancing the solar cycle CCN signal is investigated for the first time. Our global simulations indicate that a decrease in ionization rate associated with galactic cosmic ray flux change from solar minimum to solar maximum reduces annual mean nucleation rates, number concentration of condensation nuclei larger than 10 nm (CN10), and number concentrations of CCN at water supersaturation ratio of 0.8% (CCN0.8) and 0.2% (CCN0.2) in the lower troposphere by 6.8%, 1.36%, 0.74%, and 0.43%, respectively. The inclusion of 0.2 °C temperature increase enhances the CCN [cloud condensation nuclei] solar cycle signals by around 50%. The annual mean solar cycle CCN signals have large spatial and seasonal variations: (1) stronger in the lower troposphere where warm clouds are formed, (2) about 50% larger in the northern hemisphere than in the southern hemisphere, and (3) about a factor of two larger during the corresponding hemispheric summer seasons. The effect of solar cycle perturbation on CCN0.2 [cloud condensation nuclei] based on present study is generally higher than those reported in several previous studies, up to around one order of magnitude.
The paper is open access and can be downloaded here: http://iopscience.iop.org/1748-9326/9/4/045004/pdf/1748-9326_9_4_045004.pdf
h/t to The Hockey Schtick and Bishop Hill
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The clear test for this theory would be actual observations of changes in global cloud cover dependent on solar variations. Is there anyway to make such observations say through satellites?
Bob Clark
Goes hand-in-hand with Kirby’s work. seehttp://notrickszone.com/2013/05/19/cerns-jasper-kirkby-on-the-newest-unpublished-results-of-cloud-the-results-are-very-interesting/
There are obvious gross ways in which mainstream AGW thinking has (in my opinion) muddied the waters with respect to understanding climate.
One of the more subtle damages however, has been IMO to get us in the habit of thinking of simple explanations. CO2 is the control knob. How many times have we heard that?
I don’t think our climate is anywhere near that simple. I expect people will start popping up with arguments to demonstrate that cosmic rays cannot be the ‘control knob’, and that therefore Svensmark is wrong. To which I reply, there probably isn’t a single ‘control knob’ to this complicated system. This doesn’t mean cosmic rays necessarily have nothing to do with it.
As the paper concludes: ” Further research is needed to better quantify the impact of solar activities on Earth’s climate.” = please give me more money.
The problem with this kind of papers is that they ignore that solar activity and cosmic ray flux have not varied much [apart form the obvious 11- and 100-yr cycles] the past 300 years, while the climate has. For example, we are currently down to the same level of solar activity as a century ago, but the climate now is not what it was back then.
Understandably, the authors did not show a plot of solar [cosmic ray] activity.
So it fails for the last cycle – Temperature stable for 17+ years according to Monkton.
So if AGW is destroyed by this lack of temperature increase, then surely this theory is also destroyed?
Observations on Earth is key. How long before we see cooling?
Unlike lsvalgaard
(we are usually on opposite sides)
I think this makes some sense to me.
I think it explains my own results
http://blogs.24.com/henryp/2013/02/21/henrys-pool-tables-on-global-warmingcooling/
which show it is globally cooling
and it explains why the other major global data sets also show it is globally cooling
http://www.woodfortrees.org/plot/hadcrut4gl/from:1987/to:2014/plot/hadcrut4gl/from:2002/to:2014/trend/plot/hadcrut3gl/from:1987/to:2014/plot/hadcrut3gl/from:2002/to:2014/trend/plot/rss/from:1987/to:2013/plot/rss/from:2002/to:2013/trend/plot/hadsst2gl/from:1987/to:2014/plot/hadsst2gl/from:2002/to:2014/trend/plot/hadcrut4gl/from:1987/to:2002/trend/plot/hadcrut3gl/from:1987/to:2002/trend/plot/hadsst2gl/from:1987/to:2002/trend/plot/rss/from:1987/to:2002/trend
Clearly, there must be some reason as to why we are globally cooling?
HenryP says:
April 10, 2014 at 9:29 am
I think it explains my own results
This is called Confirmation Bias. Lots of that going around.
“The problem with this kind of papers is that they ignore that solar activity and cosmic ray flux have not varied much [apart form the obvious 11- and 100-yr cycles] the past 300 years, while the climate has. For example, we are currently down to the same level of solar activity as a century ago, but the climate now is not what it was back then.”
I’m anything but knowledgeable about solar activity but I doubt that we have accurate data of solar emissions for the past century. Nor is there any reason to doubt that solar emissions can have an affect simply because other factors have affected the climate over tthe past century.
The most you can say is that, IF the solar activity levels are validated as non-changing, then solar levels do not account for all climate change, which I don’t think is was ever an issue in doubt.
The effect of GCR/solar changes to CCN will only be seen in cloud data sets for areas where CCN number is the limiting factor on cloud formation. Where there are already abundant CCN and moisture is the limiting factor, GCR/solar increases in CCN production will not manifest as increased cloud cover. I am waiting for a study to look theoretically at the areas where CCN number is the limiting factor and then show us cloud data just for that region that supports the connection. I believe the data will show the connection clearly if or when that is done…until then, using large scale cloud sets with larger variabilities built in will make it difficult to distinguish the relatively small changes that might be occurring due to GCR influences.
“There are obvious gross ways in which mainstream AGW thinking has (in my opinion) muddied the waters with respect to understanding climate.One of the more subtle damages however, has been IMO to get us in the habit of thinking of simple explanations. CO2 is the control knob. How many times have we heard that? I don’t think our climate is anywhere near that simple. ”
Obviously that CO2 control knob ain’t been working lately. Another muddied water is when
the issue is overly simplified to one of “Change/No change”
Making a climate model prediction is like rolling 100 bowling balls downhill on a gravel road for a mile and predicting the exact spot where each will stop. Cosmic rays might just be one rock in that road and it could be a big one or a little one. Once you get that model up and running, lets add in doing the same run during a earthquake.
Climate science needs more work like this, investigating things other than CO2, but what a shame that some things must not be stated in papers like this, such as “this work may lessen the estimates of climate sensitivity to CO2”. Since govt funds most research it should have a vigorous policy for journals of no censorship for political reasons.
These theories based on solar observations, were used by long range weather forecaster Inigo Owen Jones and heirs Lennox and Hayden Walker who were greatly admired by Australian farmers since their long-range weather forecasting was considered to be an invaluable tool for effective farm management..
Here’s the key phrase: “the apparent correlation between observed historical solar variations and climate changes.” Literature shows correlations between berillium-10 and climate swings represented by Ice-rafting debris in the north Atlantic. See Bond, et al., here “Persistent Solar Influence on North Atlantic Climate During the Holocene.”
They write, “Our correlations are evidence, therefore, that over the last 12,000 years virtually every centennial time scale increase in drift ice documented in our North Atlantic records was tied to a distinct interval of variable and, overall, reduced solar output.
“A solar influence on climate of the magnitude and consistency implied by our evidence could not have been confined to the North Atlantic. Indeed, previous studies have tied increases in the Δ14C of tree rings, and hence, reduced solar irradiance, to Holocene glacial advances in Scandinavia (15); expansions of the Holocene Polar atmospheric circulation above Greenland (16); an abrupt cooling in the Netherlands about 2700 years ago (17); and lacustrine records from the Faroe Islands (18). All of these events closely match prominent increases in North Atlantic drift ice (Fig. 3, A and B).”
The observations are key. They provide direct evidence of a strong solar-climate link.
Protests against this conclusion referencing the small changes in TSI do not dismiss the evidence. Such protests just admit of a lack of understanding in the solar-climate effect. I.e., the theory of the solar-climate connection is inadequate to explain the observations.
Lack of a solar-climate theory does not refute the solar-climate evidence. The meaning of the isotopic solar-climate signature, after all, is grounded in nuclear physics not in solar climatology.
Lief: “For example, we are currently down to the same level of solar activity as a century ago,”
This ignores a buffered or delayed effect. I would say that the prior five cycles have been larger than average. You need to warm and cool the oceans in order to see much movement. And you need to include ocean cycles in your analysis. Just doing a single cycle single element analysis is not science.
I fear I have to agree with Leif Svalgaard (lsvalgaard above). The authors are are a long ways from meeting their burden of proof.
This paper is about how much the sun’s variation affects the temperature.
It seems to me that the very first thing that one would need to do is to show that there IS a solar influence on climate, then we could talk about how much influence there is. They say, for example:
But what they never do is show us the “apparent correlation between observed historical solar variations and climate changes” … heck, as Leif points out, they never even show us a plot of the variations in what they claim is the main variable, cosmic ray activity.
Look, I’ve spent a good chunk of my work on climate searching fruitlessly for some relationship, any relationship, between solar variations and climate. But like the study involving sunspots and the Parana River or the study about sunspots and sea level, as soon as I’ve looked at the claimed “apparent correlation between observed historical solar variations and climate changes” they’ve evaporated into thin air.
And these authors don’t help us in that regard. They make the following statement:
Scafetta? Really? Look, folks, anyone citing Scafetta might as well just wear a sign ,,,
I also looked at the Douglass and Clader study and wasn’t impressed. They claim a correlation between TSI and lower troposphere temperatures. I looked and couldn’t find it. Well, not exactly. A cross-correlation analysis finds a weak negative correlation with a lag of about 2 years, but when I divide the data in half, I find that the correlation disappears entirely. In addition … why would the correlation be negative, with temperatures decreasing as solar levels increase? That makes no sense, and increases the odds that the correlation is spurious.
And this is consistent with everything else that I’ve found regarding sun-temperature correlation. IF the ~11 variations in solar irradiance are affecting the temperature, the signal is vanishingly small. If it weren’t, we’d have isolated and analyzed it long ago. This aspect of climate has been studied since the 1800s, and to date, nobody I know of has ever shown any kind of strong correlation between the 11-year solar cycles and the weather.
Finally, the authors detail their method for doing the study, viz:
So once again, it’s models all the way down. No data were harmed (or even used) in the analysis.
Me, I’d place absolutely no credence in this study at all. They haven’t shown the simplest evidence that their claimed correlation between the sun and the weather even exists, much less that it shows what they are claiming.
w.
For the connection between cosmic ray flux and climate see Fig8 at
http://climatesense-norpag.blogspot.com/2013/10/commonsense-climate-science-and.html
I say here
“NOTE !! the connection between solar “activity” and climate is poorly understood and highly controversial. Solar ” activity” encompasses changes in solar magnetic field strength, IMF, CRF, TSI ,EUV, solar wind density and velocity, CMEs, proton events etc. The idea of using the neutron count as a useful proxy for changing solar activity and temperature forecasting is agnostic as to the physical mechanisms involved.”
However as the Watts piece shows it appears increasingly likely that the cosmic ray flux via the Svensmark mechanism may be the principal driver.
See several other posts at
http://climatesense-norpag.blogspot .com
for a forecast of the timing and amount of the possible coming cooling based on the natural 60 and 1000 year quasi periodicities in the temperature data and the neutron count and 10Be as the most useful proxy for solar activity.
lsvalgaard
http://wattsupwiththat.com/2014/04/10/more-support-for-svensmarks-cosmic-ray-modulation-of-earths-climate-hypothesis/#comment-1609873
henry says
you have proven my point
(of habitually not being on my side)
but clearly you have not explained why all major data sets show we are globally cooling?
http://www.woodfortrees.org/plot/hadcrut4gl/from:1987/to:2014/plot/hadcrut4gl/from:2002/to:2014/trend/plot/hadcrut3gl/from:1987/to:2014/plot/hadcrut3gl/from:2002/to:2014/trend/plot/rss/from:1987/to:2013/plot/rss/from:2002/to:2013/trend/plot/hadsst2gl/from:1987/to:2014/plot/hadsst2gl/from:2002/to:2014/trend/plot/hadcrut4gl/from:1987/to:2002/trend/plot/hadcrut3gl/from:1987/to:2002/trend/plot/hadsst2gl/from:1987/to:2002/trend/plot/rss/from:1987/to:2002/trend
We have two problems:
1) Why is the global temperature so stable over time and
2) Why does it change, when it does, from time to time.
A) IMHO water, covering most of the earth’s surface, having a maximum density at 4 degrees C, would cause all manner of self regulatory behaviour wrt temperature.
B) External influences such as cosmic rays, described above fit the bill.
Sadly the actual observations of low cloud percentages.. clouds at 1018hPa, 991hpa, 887 hpa, 771hpa, 648 hpa,548hpa. and 447hPa show NO RELATIONSHIP between changes in GCR and changes in clouds. None. Zip. zero.
That no changes at all low altitudes however you want to define that.
No changes by season
No changes by latitude
No changes by season*latitude
I first encountered this theory several years ago in a series of articles in the Canadian National Post. There are fairly complete records of sunspot activity since Galileo discovered them.
What I would like to find out is if there are satellite records of the changes in Earth’s albedo, and how does that match up with the recent sunspot record? Might tell us a lot…
http://fullcomment.nationalpost.com/2011/06/16/lorne-gunter-global-warming-try-global-cooling/
The anti-solar crowd are never biased, or have money or other personal motivations other than pure science. Yessiree Bob.
Tilo says:
April 10, 2014 at 10:07 am
This ignores a buffered or delayed effect.
Svensmark in his various papers claim a direct effect with no delay….
Bruce Cobb says:
April 10, 2014 at 10:14 am
The anti-solar crowd are never biased, or have money or other personal motivations other than pure science
Very perceptive. It is time that such a view is supported by more than just you.
Whats needed, as others point out, is a detailed statistical study of what has actually happened to cloud in the era in which we have data (from about 1983) via the International Satellite Cloud Climatology Project – at different levels, optical thickness, and spatial distribution, and the correlated (or not) with cosmic ray flux – as per Svensmark’s original paper covering solar cycle 22. Svensmark himself extrapolated to cycle 23, but his methods were criticised in the science literature – that does not mean he was wrong, but as far as I am aware, he only responded on the website of the Danish Space Agency – and that is not an adequate peer-reviewed response, at least not in this polarised arena. So where are the studies for cycle 24? Or the period through 2008 when global temperatures dropped so precipitously – what was happening with clouds and cosmic rays then? Instead – Svensmark disappears to a well-funded lab to do chemistry experiments which will never be acceptable for a real-world atmosphere. Why is no-one doing the detailed cloud assessments. This is the real key to natural variability.