By Dr. Roy Spencer, PhD (reprinted from his blog with permission)
UPDATE (12:35 p.m. CDT 19 May 2011): revised corrections of CERES data for El Nino/La Nina effects.
While I have been skeptical of Svensmark’s cosmic ray theory up until now, it looks like the evidence is becoming too strong for me to ignore. The following results will surely be controversial, and the reader should remember that what follows is not peer reviewed, and is only a preliminary estimate.
I’ve made calculations based upon satellite observations of how the global radiative energy balance has varied over the last 10 years (between Solar Max and Solar Min) as a result of variations in cosmic ray activity. The results suggest that the total (direct + indirect) solar forcing is at least 3.5 times stronger than that due to changing solar irradiance alone.
If this is anywhere close to being correct, it supports the claim that the sun has a much larger potential role (and therefore humans a smaller role) in climate change than what the “scientific consensus” states.
BACKGROUND
The single most frequently asked question I get after I give my talks is, “Why didn’t you mention the sun?” I usually answer that I’m skeptical of the “cosmic ray gun” theory of cloud changes controlling climate. But I point out that Svensmark’s theory of natural cloud variations causing climate change is actually pretty close to what I preach — only the mechanism causing the cloud change is different.
Then, I found last year’s paper by Laken et al. which was especially interesting since it showed satellite-observed cloud changes following changes in cosmic ray activity. Even though the ISCCP satellite data they used are not exactly state of the art, the study was limited to the mid-latitudes, and the time scales involved were days rather than years, the results gave compelling quantitative evidence of a cosmic ray effect on cloud cover.
With the rapid-fire stream of publications and reports now coming out on the subject, I decided to go back and spend some time analyzing ground-based galactic cosmic ray (GCR) data to see whether there is a connection between GCR variations and variations in the global radiative energy balance between absorbed sunlight and emitted infrared energy, taken from the NASA CERES radiative budget instruments on the Terra satellite, available since March 2000.
After all, that is ultimately what we are interested in: How do various forcings affect the radiative energy budget of the Earth? The results, I must admit, are enough for me to now place at least one foot solidly in the cosmic ray theory camp.
THE DATA
The nice thing about using CERES Earth radiative budget data is that we can get a quantitative estimate in Watts per sq. meter for the radiative forcing due to cosmic ray changes. This is the language the climate modelers speak, since these radiative forcings (externally imposed global energy imbalances) can be used to help calculate global temperature changes in the ocean & atmosphere based upon simple energy conservation. They can then also be compared to the estimates of forcing from increasing carbon dioxide, currently the most fashionable cause of climate change.
From the global radiative budget measurements we also get to see if there is a change in high clouds (inferred from the outgoing infrared measurements) as well as low clouds (inferred from reflected shortwave [visible sunlight] measurements) associated with cosmic ray activity.
I will use only the ground-based cosmic ray data from Moscow, since it is the first station I found which includes a complete monthly archive for the same period we have global radiative energy budget data from CERES (March 2000 through June 2010). I’m sure there are other stations, too…all of this is preliminary anyway. Me sifting through the myriad solar-terrestrial datasets is just as confusing to me as most of you sifting through the various climate datasets that I’m reasonably comfortable with.
THE RESULTS
The following plot (black curve) shows the monthly GCR data from Moscow for this period, as well as a detrended version with 1-2-1 averaging (red curve) to match the smoothing I will use in the CERES measurements to reduce noise.
Detrending the data isolates the month-to-month and year-to-year variability as the signal to match, since trends (or a lack of trends) in the global radiative budget data can be caused by a combination of many things. (Linear trends are worthless for statistically inferring cause-and-effect; but getting a match between wiggles in two datasets is much less likely to be due to random chance.)
The monthly cosmic ray data at Moscow will be compared to global monthly anomalies the NASA Terra satellite CERES (SSF 2.5 dataset) radiative flux data,
which shows the variations in global average reflected sunlight (SW), emitted infrared (LW), and Net (which is the estimated imbalances in total absorbed energy by the climate system, after adjustment for variations in total solar irradiance, TSI). Note I have plotted the variations in the negative of Net, which is approximately equal to variations in (LW+SW)
Then, since the primary source of variability in the CERES data is associated with El Nino and La Nina (ENSO) activity, I subtracted out an estimate of the average ENSO influence using running regressions between running 5-month averages of the Multivariate ENSO Index (MEI) and the CERES fluxes. I used the MEI index along with those regression coefficients in each month to correct the CERES fluxes 4 months later, since that time lag had the strongest correlation.
Finally, I performed regressions at various leads and lags between the GCR time series and the LW, SW, and -Net radiative flux time series, the results of which are shown next.
The yearly average relationships noted in the previous plot come from this relationship in the reflected solar (SW) data,
while the -Net flux (Net is absorbed solar minus emitted infrared, corrected for the change in solar irradiance during the period) results look like this:
It is that last plot that gives us the final estimate of how a change in cosmic ray flux at Moscow is related to changes in Earth’s radiative energy balance.
SUMMARY
What the above three plots show is that for a 1,000 count increase in GCR activity as measured at Moscow (which is somewhat less than the increase between Solar Max and Solar Min), there appears to be:
(1) an increase in reflected sunlight (SW) of 0.64 Watts per sq. meter, probably mostly due to an increase in low cloud cover;
(2) virtually no change in emitted infrared (LW) of +0.02 Watts per sq. meter;
(3) a Net (reflected sunlight plus emitted infrared) effect of 0.55 Watts per sq. meter loss in radiant energy by the global climate system.
WHAT DOES THIS MEAN FOR CLIMATE CHANGE?
Assuming these signatures are anywhere close to being real, what do they mean quantitatively in terms of the potential effect of cosmic ray activity on climate?
Well, just like any other forcing, a resulting temperature change depends not only upon the size of the forcing, but also the sensitivity of the climate system to forcing. But we CAN compare the cosmic ray forcing to OTHER “known” forcings, which could have a huge influence on our understanding of the role of humans in climate change.
For example, if warming observed in the last century is (say) 50% natural and 50% anthropogenic, then this implies the climate system is only one-half as sensitive to our greenhouse gas emissions (or aerosol pollution) than if the warming was 100% anthropogenic in origin (which is pretty close to what we are told the supposed “scientific consensus” is).
First, let’s compare the cosmic ray forcing to the change in total solar irradiance (TSI) during 2000-2010. The orange curve in following plot is the change in direct solar (TSI) forcing between 2000 and 2010, which with the help of Danny Braswell’s analytical skills I backed out from the CERES Net, LW, and SW data. It is the only kind of solar forcing the IPCC (apparently) believes exists, and it is quite weak:
Also shown is the estimated cosmic ray forcing resulting from the month-to-month changes in the original Moscow cosmic ray time series, computed by multiplying those monthly changes by 0.55 Watts per sq. meter per 1,000 cosmic ray counts change.
Finally, I fitted the trend lines to get an estimate of the relative magnitudes of these two sources of forcing: the cosmic ray (indirect) forcing is about 2.8 times that of the solar irradiance (direct) forcing. This means the total (direct + indirect) solar forcing on climate associated with the solar cycle could be 3.8 times that most mainstream climate scientists believe.
One obvious question this begs is whether the lack of recent warming, since about 2004 for the 0-700 meter layer of the ocean, is due to the cosmic ray effect on cloud cover canceling out the warming from increasing carbon dioxide.
If the situation really was that simple (which I doubt it is), this would mean that with Solar Max rapidly approaching, warming should resume in the coming months. Of course, other natural cycles could be in play (my favorite is the Pacific Decadal oscillation), so predicting what will happen next is (in my view) more of an exercise in faith than in science.
In the bigger picture, this is just one more piece of evidence that the IPCC scientists should be investigating, one which suggests a much larger role for Mother Nature in climate change than the IPCC has been willing to admit. And, again I emphasize, the greater the role of Nature in causing past climate change, the smaller the role humans must have had, which could then have a profound impact on future projections of human-caused global warming.
Stephen Wilde says:
May 22, 2011 at 12:09 am
Furthermore I seem to recall Leif previously telling me that the sun was as active in the 1780s as it was in the late 20th Century yet the atmospheric temperatures were not the same.
Now he says that cycle 5 peaking in 1790 was one of the smallest !!
SC 5 didn’t begin until ~1798.
For TonyB.
Data before 1650 are sporadic, difficult to make any definitive conclusions.
However Loehle reconstruction indeed shows that the early years of 17th century (1600-1615) were the coldest on record.
http://www.vukcevic.talktalk.net/LL.htm
Your supposition that the coolest point in the LIA was 1607 appear to be correct.
Clearly ENSO has not been adjusted for sufficiently. 2007-2010 there is no correlation between GCR and reflected SW.
Vuk:
The ocean currents and gyres are the primary energy transportation mechanism for the Terrestrial heat engine. That heat engine is driven by the Sun’s energy, and the amount of solar energy entering the ocean is modulated by changing amounts of cloud cover.
Roy Spencer and Nir Shaviv find from empirical observation that the Sun’s TSI variation is amplified at Earth’s surface. The ISCCP and earthshine folks find from empirical observation that cloud cover was lower in the warming period, and increased after the 1998 el nino, since which event, warming has been negligible.
Leif Svalgaard can twitter about GCM’s and aerosol theory if that is what floats his boat, but I’ll go with observed reality every time.
Correction:
It should be Loehle reconstruction
tallbloke says: May 22, 2011 at 2:48 am
…………………
Ocean conveyor belt has large thermal inertia and hysteresis.
In a system with hysteresis, is not possible to predict the system’s output at an instant in time given only its input at that instant in time.
The output depends in part on the internal state of system and not only on its input. There is no way to predict the system’s output without looking at the history of the input, i.e. to determine the path that the input followed before it reached its current state or knowing accurately the internal state of the system.
Hence TSI and cloud variability which should produce an immediate heating/cooling effect, are averaged during long periods. Ocean conveyor belt collects heat for decades and even centuries in the equatorial areas before it reaches Nordic seas; it takes more than 1500 years to complete a single cycle, for that purpose, the short term variability of the solar output is smoothed out to a degree where idea of constancy is a plausible starting point.
David L. Hagen says:
May 21, 2011 at 1:39 pm (Edit)
Shaviv comes to similar conclusions:
Subject to the above caveats and those described in the text, the
CRF/climate link therefore implies that the increased solar luminosity and reduced
CRF over the previous century should have contributed a warming of 0.47 ± 0.19 K, while the rest should be mainly attributed to anthropogenic causes. Without any effect of cosmic rays, the increase in solar luminosity would correspond to an increased temperature of 0.16 ± 0.04 K.
Shaviv, N. J. (2005), On climate response to changes in the cosmic ray flux and radiative budget, J. Geophys. Res., 110, A08105, doi:10.1029/2004JA010866.
Note the ratio total to luminosity alone is about 2.9, similar to Spencer’s 3.5 above.
Thanks David. That paper is an interesting read. Particularly for the clear laying out of uncertainties and assumptions involved in estimating climate sensitivity.
vukcevic says:
May 22, 2011 at 3:16 am
Ocean conveyor belt collects heat for decades and even centuries in the equatorial areas before it reaches Nordic seas; it takes more than 1500 years to complete a single cycle, for that purpose, the short term variability of the solar output is smoothed out to a degree where idea of constancy is a plausible starting point.
It is the short term variability which introduces the hiccups and lumps in the long term flows and cycles, e.g. the changes in the sub-polar gyre you mentioned.
Oceanic heat retention and release is happening at all timescales from days to geological timescales. Within that spread of timescales it is possible to identify and postulate causes (or at least the underlying cause of several confounded mechanisms) through correlated periodicities because of the long timescales on which the ocean maintains thermal boundaries in layers and flows.
lgl says:
May 22, 2011 at 2:39 am (Edit)
Clearly ENSO has not been adjusted for sufficiently. 2007-2010 there is no correlation between GCR and reflected SW.
Correct. Nir Shaviv explicitly states in the paper David Hagen linked that ENSO is assumed to average out. Given what Bob Tisdale has discovered, this means we shouldn’t expect good correlations on periods less than 60 years or so.
John Finn says:
May 22, 2011 at 2:27 am
SC 5 didn’t begin until ~1798.
Yet you asserted that the Dalton Minimum started in 1790, at the peak of a high cycle?
BTW Stephen, a small confusion has arisen because the cycle ending in 1755 is numbered zero not one.
tallbloke says: May 22, 2011 at 5:11 am
It is the short term variability which introduces the hiccups and lumps in the long term flows and cycles, e.g. the changes in the sub-polar gyre you mentioned.
Wouldn’t think so, subpolar gyre is far too strong for any of those, btw. it takes more than 20 years to complete one cycle. It controls atmospheric low above it, which in turn diverts polar jet-stream, controlling short and long term weather patterns in the north Atlantic. Similar with Aleutian low in North Pacific. All recent talk of Atlantic-Pacific teleconnection is another climate change blind alley.
Anyone using a decade or so to determine long term change in the climate patters is starting from a wrong premise, there were number of those 1750-1900, 150 years of decadal oscillations, but no long term change on the century scale.
Nigel Calder takes an upbeat view on Spencers article:
http://calderup.wordpress.com/2011/05/21/roll-up-roll-up-for-the-paradigm-shift/
vukcevic says:
May 22, 2011 at 5:51 am
Wouldn’t think so, subpolar gyre is far too strong for any of those, btw. it takes more than 20 years to complete one cycle.
Maybe were talking at cross purposes. As I understand it, gyres are a product of the coriolis effect acting on the poleward motion of ocean currents. The principle forces involved are planetary rotation and solar radiation absorbed mostly in the equatorial region.
Do we agree so far?
Partially. The spg is specific, its strength is determined by ratio of cold currents across the Greenland-Scotland ridge, and the branch of the NA drift current.
http://www.aoml.noaa.gov/phod/accp/ma97/fig1_mike.jpg
I’m off line now.
tallbloke says:
May 21, 2011 at 11:46 pm
Very deceptive. The sun’s activity has suddenly dropped in the last few years from very high to very low levels.
See my reply to Corcoran:
David Corcoran says:
May 21, 2011 at 2:04 pm
“I’d love to read your peer-reviewed publications regarding the relationship (or lack of it) between charged particles and clouds. ”
Solar activity [as measured by the sun’s magnetic field in the heliosphere, which most people think controls the entry of cosmic rays into the solar system] in the past 50 years has not been markedly higher than 150-years ago, e.g. Figure 10 of http://www.leif.org/research/2009JA015069.pdf The climate has been rather different though. This is to me a simple refutation that the GCR flux cannot be a major player in the climate debate.
To pretend that it is already sufficiently well understood to be used as a disproof of the Svensmark effect on the basis of a GCM and inadequate aerosol microphysics theory is laughable.
It is not about aerosol microphysics, but about how cloud microphysics. http://adsabs.harvard.edu/abs/2010AGUFM.A11H..02L
Graybill tree rings?
Carbon 14 is used to assess the cosmic ray intensity in the past. Here is how it works: http://c14.arch.ox.ac.uk/embed.php?File=calibration.html
Go educate yourself
Stephen Wilde says:
May 22, 2011 at 12:09 am
Now he says that cycle 5 peaking in 1790 was one of the smallest !!!
Solar cycle 5 started in June 1798 and ended in July 1810 having a maximum of SSN=52.5, the second smallest on record.
HenryP says:
May 21, 2011 at 11:22 pm
So do you agree with me that global warming is due to natural causes rather than human influences?
You are very likely correct. Climate changes all the time. There is no single cause on short time scales. Over thousands of year orbital changes, over millions of years distribution of land and sea, and over billions of years solar luminosity become dominant causes.
vukcevic says:
May 22, 2011 at 1:29 am
Here are some quotes from my article, now half finished.
None of this has any bearing on solar activity
Leif Svalgaard says:
May 22, 2011 at 7:08 am
Solar activity [as measured by the sun’s magnetic field in the heliosphere, which most people think controls the entry of cosmic rays into the solar system] in the past 50 years has not been markedly higher than 150-years ago, e.g. Figure 10 of http://www.leif.org/research/2009JA015069.pdf The climate has been rather different though.
I don’t think we have sufficiently good data to say much about global climate in 1860, apart from to say it was near the peak of a upswing (like now), along the course of a general recovery from the little ice age (a function of OHC accumulation).
David Hagen linked a good paper by Nir Shaviv which quantifies possible GCR effects at different time periods and time scales :
http://www.phys.huji.ac.il/~shaviv/articles/2004JA010866.pdf
“Go educate yourself”, yourself.
The GHG models all predict a tropical hot spot. This has never been observed. In any other branch of science this would constitute falsification of the greenhouse theory.
People want to believe that humans are responsible for climate change, because then something can be done. Sacrifices can be made. Dances can be danced.
The idea that climate change is natural and there is nothing we can do about it. That is something that people don’t want to believe. It means there is nothing we can do.
Someone comes along and say “do as I say and I will fix the weather”. People WANT to believe and there are plenty of people that will take advantage of this.
Convince a healthy person they have cancer and they will pay you every penny they have to “cure” them. Give us your money and you will be saved. Sound familiar?
IPCC = snake oil salesman to the world.
tallbloke says:
May 22, 2011 at 7:28 am
I don’t think we have sufficiently good data to say much about global climate in 1860
If the data doesn’t fit, you declare the data no good. Fair enough, one can always do that.
http://www.leif.org/research/Loehle-Temps-and-TSI.png shows Loehle’s reconstruction of temperatures.
The Nir Shaviv paper which quantifies possible GCR […] is based on obsolete data such as Solanki and Fligge [1998], Hoyt and Schatten [1993], and Lean et al. [1995].
But, of course, if the [obsolete] data fits, you declare the data good.
“Solar activity [as measured by the sun’s magnetic field in the heliosphere, which most people think controls the entry of cosmic rays into the solar system] ”
the conclusion I read is:
proxy (GCR) climate
proxy(magnetic fields) climate
therefore
proxy(magnetic fields) proxy(GCR)
this would not be the first time that “which most people think” turns out to be wrong.
aargh. html
proxy (GCR) –correlate– climate
proxy(magnetic fields) –not correlate– climate
therefore
proxy(magnetic fields) –not– proxy(GCR)
“is based on obsolete data”
the age of the data is irrelevant. the question is:
1. Was the data collected using appropriate controls to prevent experimenter contamination?
2. Has the data been independently recreated and validated?
By that criteria a lot of recent climate data is worthless. It was collected in such a fashion that the experimenter was in a position to influence the results and the results have not been independently confirmed.
Leif Svalgaard says:
May 22, 2011 at 7:44 am
The Nir Shaviv paper which quantifies possible GCR […] is based on obsolete data such as Solanki and Fligge [1998], Hoyt and Schatten [1993], and Lean et al. [1995].
But, of course, if the [obsolete] data fits, you declare the data good.
I know those values are bracketed by estimates which are higher and lower, such as those from Shapiro and yourself. As such, I regard them as averagely plausible, though as always, I keep an eye on developments, and maintain a healthy skepticism regarding those who stridently claim they are right and everyone else is wrong.
Tall bloke says:
HenryP says:
May 21, 2011 at 11:22 pm
It appears from my own statistical analyses that it is the increasing maximum temperature that drove up the mean temperature on earth. (over the past 35 years)
http://www.letterdash.com/HenryP/henrys-pool-table-on-global-warming
So do you agree with me that global warming is due to natural causes rather than human influences?
Nice work and a fair question.
HenryP
thanks
Leif Svalgaard says:
HenryP says:
May 21, 2011 at 11:22 pm
So do you agree with me that global warming is due to natural causes rather than human influences?
You are very likely correct. Climate changes all the time. There is no single cause on short time scales. Over thousands of year orbital changes, over millions of years distribution of land and sea, and over billions of years solar luminosity become dominant causes.
HenryP
Thanks Leif. I could not look at longer timescales going back because I don’t trust the data. In fact I suspect that even since the time that I peeked (from 1974), equipment could have already improved which may have had an affect on the results. Never mind all of that, even if a large % of the observed increases is simply due to error (which would probably affect higher temps. more than lower temps.), the fact would then still remain that it is maximum temperatures that have driven up the average global temperatures during the past 35 years…
The work I did was relatively simple. Anyone who did Statistics 1 can do it. And he/she should be able to repeat it, if you take your samples randomly. The point I want to make is that the largest increase in CO2 was exactlty during these past 35 years. So should we not be reading in the newspapers soon that modern warming was and is not caused by an increase in GHG’s?
You tall guys have to fight it out between you as to what did cause warming or what is still causing it. All I am saying that it was not the increase in carbon dioxide that did it.
Are you with me?
tallbloke says:
May 22, 2011 at 8:17 am
I keep an eye on developments, and maintain a healthy skepticism regarding those who stridently claim they are right and everyone else is wrong.
then you should welcome a development where everyone now begin to agree:
http://adsabs.harvard.edu/abs/2011JGRA..11604109L
“Svalgaard and Cliver (2010) recently reported a consensus between the various reconstructions of the heliospheric field over recent centuries. This is a significant development because, individually, each has uncertainties introduced by instrument calibration drifts, limited numbers of observatories, and the strength of the correlations employed. However, taken collectively, a consistent picture is emerging. We here show that this consensus extends to more data sets and methods than reported by Svalgaard and Cliver, including that used by Lockwood et al. (1999), when their algorithm is used to predict the heliospheric field rather than the open solar flux…”
Leif Svalgaard says:
May 22, 2011 at 8:24 am
then you should welcome a development where everyone now begin to agree:
http://adsabs.harvard.edu/abs/2011JGRA..11604109L
Everyone?
Everyone you think matters obviously. 😉
Being the sceptic I am, I’m not convinced by a consensus of the limited subset of funded scientists who agree. Especially when they are funded by an establishment hell bent on removing the sun from the playing field of significant climate drivers for non scientific reasons. But in any case, my methodology can cope with pretty much any reconstruction no matter how much it squashes solar variability, just so long as you don’t manage to build a consensus which reduces it to zero.