New paper demonstrates that climate responds to short and long-term changes in solar activity

(Via the Hockey Schtick) A new peer reviewed paper published in The Holocene finds a significant link between solar activity and climate over the past 1000 years. According to the authors:

“Our results suggest that the climate responds to both the 11 yr solar cycle and to long-term changes in solar activity and in particular solar minima.”

The authors also find “a link between the 11 yr solar cycle and summer precipitation variability since around 1960” and that:

“Solar minima are in this period associated with minima in summer precipitation, whereas the amount of summer precipitation increases during periods with higher solar activity.”

IRBSi is the proxy for precipitation/climate change and shows good agreement with solar activity. Figure 12. The comparison between the graphs of the IR-BSi and that of the solar cycles shows good agreement between the percentage of mineral materials of allochthonous and solar cycles reconstructed on the basis of changes in concentrations of 14 C in macrofossils. A good agreement is also evident between the concentrations of 18 O of foraminifera in the Norwegian Sea and the index IR-BSi.

Solar forcing of climate during the last millennium recorded in lake sediments from northern Sweden

U Kokfelt   University of Copenhagen, Denmark

R Muscheler Lund University, Sweden

Abstract

We report on a sediment record from a small lake within the subarctic wetland complex Stordalen in northernmost Sweden covering the last 1000 years. Variations in the content of minerogenic material are found to follow reconstructed variations in the activity of the Sun between the 13th and 18th centuries. Periods of low solar activity are associated with minima in minerogenic material and vice versa. A comparison between the sunspot cycle and a long instrumental series of summer precipitation further reveals a link between the 11 yr solar cycle and summer precipitation variability since around 1960. Solar minima are in this period associated with minima in summer precipitation, whereas the amount of summer precipitation increases during periods with higher solar activity. Our results suggest that the climate responds to both the 11 yr solar cycle and to long-term changes in solar activity and in particular solar minima, causing dry conditions with resulting decreased runoff.

============================================================

Recall that a paper published last year in Astronomy & Astrophysics shows solar activity at end of 20th century was near highest levels of past 11,500 years.

A paper published by a researcher at Max-Planck-Institute in Astronomy & Astrophysics reconstructs solar activity over the Holocene and finds solar activity at the end of the 20th century was near the highest levels of the entire 11,500 year record. The reconstruction spans the past 2,500 years, and the paper shows a ‘hockey stick’ of solar activity, following the end of the Little Ice Age in the 1800’s.

TSI_weighted_Fig11

Fig. 11. TSI weighted reconstruction since approximately 9500 BC. In order to provide a better visualization, the evolution since 1000 BC is displayed in panel (b). The filled gray band represents region limited by the KN08-VADM and KC05-VDM reconstructions.

For reference, the red lines represent the 10-year averaged reconstruction by Krivova et al. (2010a).

Evolution of the solar irradiance during the Holocene

L. E. A. Vieira1,2, S. K. Solanki1,3, N. A. Krivova1 and I. Usoskin4

Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Str. 2, 37191 Katlenburg-Lindau, Germany

Laboratoire de Physique et Chimie de l’Environnement et de l’Espace (LPC2E/CNRS), 3A, Avenue de la Recherche, 45071 Orléans Cedex 2, France

School of Space Research, Kyung Hee University, Yongin, Gyeonggi, 446-701, Korea

Sodankyla Geophysical Observatory (Oulu Unit), POB 3000, Universiy of Oulu, Finland

Abstract

Context. Long-term records of solar radiative output are vital for understanding solar variability and past climate change. Measurements of solar irradiance are available for only the last three decades, which calls for reconstructions of this quantity over longer time scales using suitable models.

Aims.

We present a physically consistent reconstruction of the total solar irradiance for the Holocene.

Methods. 

We extend the SATIRE (Spectral And Total Irradiance REconstruction) models to estimate the evolution of the total (and partly spectral) solar irradiance over the Holocene. The basic assumption is that the variations of the solar irradiance are due to the evolution of the dark and bright magnetic features on the solar surface. The evolution of the decadally averaged magnetic flux is computed from decadal values of cosmogenic isotope concentrations recorded in natural archives employing a series of physics-based models connecting the processes from the modulation of the cosmic ray flux in the heliosphere to their record in natural archives. We then compute the total solar irradiance (TSI) as a linear combination of the jth and jth + 1 decadal values of the open magnetic flux. In order to evaluate the uncertainties due to the evolution of the Earth’s magnetic dipole moment, we employ four reconstructions of the open flux which are based on conceptually different paleomagnetic models.

Results. 

Reconstructions of the TSI over the Holocene, each valid for a different paleomagnetic time series, are presented. Our analysis suggests that major sources of uncertainty in the TSI in this model are the heritage of the uncertainty of the TSI since 1610 reconstructed from sunspot data and the uncertainty of the evolution of the Earth’s magnetic dipole moment. The analysis of the distribution functions of the reconstructed irradiance for the last 3000 years, which is the period that the reconstructions overlap, indicates that the estimates based on the virtual axial dipole moment are significantly lower at earlier times than the reconstructions based on the virtual dipole moment. We also present a combined reconstruction, which represents our best estimate of total solar irradiance for any given time during the Holocene.

Conclusions. 

We present the first physics-based reconstruction of the total solar irradiance over the Holocene, which will be of interest for studies of climate change over the last 11 500 years. The reconstruction indicates that the decadally averaged total solar irradiance ranges over approximately 1.5 W/m2 from grand maxima to grand minima.

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What I find interesting is that the 1.5 W/m2 isn’t far from the value for CO2 forcing reported by CDIAC here:

http://cdiac.ornl.gov/pns/current_ghg.html

CDIAC_CO2_forcigs_table

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Stevo

The case against AGW just gets stronger and stronger. Love it.

Doug Proctor

An article of great interest, but not useful in the CAGW debate, unfortunately.
Variations in TSI as noted are sufficient but not necessary for the late 20th century warming: this is the problem of combating CAGW. It’s the “many roads to Mecca” problem. CO2 by IPCC narrative is sufficient to account for modern warming. Other possible means of warming, even if of historical importance, once discounted for the present, are not considerations in the argument.
So far the unique attributes of CO2 warming, the mid-tropospheric “hotspot”, the temperature rise in conjunction with CO2, are staggering around in the minimal range, allowing the warmist to believe that, with time, the comparison of expectations to observations will improve. To date, there are no unique TSI or (as I suspect) heat redistribution or other, non-CO2 signs we can point to for the skeptical defense.
We need something in this line.

RHS

Wasn’t the CO2 lifetime in the atmosphere at 100 years dropped/debunked to something closer 5, maybe 10?

rgbatduke

Counting down for Lief to come in and comment … 3, 2, 1…
The question as to whether or not the 20th century is really a grand solar maximum as indicated by at least sunspot count is (apparently) open and debatable, given that Ushokin and colleagues steadfastly seem to disagree with Lief in this regard. The paper above seems to be quite recent and appears to (again) rely on radioactive proxies, with some control for our lack of certainty concerning the relative contribution from solar magnetic and geomagnetic screenings.
The other interesting thing to do would be to plot Ushokin’s result above against global temperature estimates over the Holocene, and then look at multivariate linear models (at least) including at least a few computable functions, such as the precession of the axis of rotation over that same timescale.
Anybody got any popcorn?
rgb

As usual, people are willing to paper over the obvious discrepancies to support whatever cause they adhere to. Overlaying the two reconstructions of solar activity shown in this post shows the problem:
http://www.leif.org/research/Last-1000-Years-Solar-Modulation.png
The brown curve [Muscheler] shows no long-term trend since 1700 consistent with sunspot and geomagnetic data. The 18th century was as active [or even more] as the 20th. The red curve [Solanki] shows the ‘most active in 10,000 years’ myth. Clearly both curves cannot be correct, yet both are taken as support. Go figure.
There is substantial evidence that some of the ‘dips’ in solar activity measured with radionuclides are not representative of solar modulation but:
“This is a particular problem for historical projections of solar activity based on ice core measurements which assume a 1:1 correspondence. We have made other tests of the correspondence between the 10Be predictions and the ice core measurements which lead to the same conclusion, namely that other influences on the ice core measurements, as large as or larger than the production changes themselves, are occurring. These influences could be climatic or instrumentally based.”
http://arxiv.org/ftp/arxiv/papers/1004/1004.2675.pdf

Johanus

Anthony Watts:
“… the paper shows a ‘hockey stick’ of solar activity, following the end of the Little Ice Age in the 1800′s.”
I see an equally large ‘hockey-stick’ jump at 9000BC. Also smaller ones around 8000BC, 7000BC, 3500BC, 700BC and 350BC etc. I think these multiple occurrences, if valid, dismantle all of the AGW/CAGW “what-else-could-it-be?” arguments, because it would no longer be possible to characterize any modern hockey-stick as “unprecedented”.

rgbatduke

Wasn’t the CO2 lifetime in the atmosphere at 100 years dropped/debunked to something closer 5, maybe 10?
According to who? There are many models that can fit the data (including the Bern model with its long lifetime). The problem is once again the difficulty of resolving the models. Fluctuation-dissipation is really the only possible way to do so, and sadly global CO_2 increases like a very nearly smooth function with a small annual/seasonal sawtooth. To get good measurements one would have to do something like inject a huge bolus of CO_2 into the atmosphere all at once and then watch how long it takes to decay back to quasi-equilibrium, or introduce in some other way a large enough fluctuation that the dissipation information would tell you something about timescales of the underlying equilibration ODEs.
Bart and Richard have done something of that (and I dabbled with it too, using octave to generate simple model fits) on another thread a year or so ago. I’d say that it is fair(er) to say that the Bern model is neither verified by any particular set of observations nor falsified by others; it remains a candidate, but there are indeed other models that make a fair bit of physical sense that would produces a much shorter equilibration time and indicate a much shorter effective lifetime.
Part of the difficulty is knowing exactly how to set the parameters that indicate what the ocean is doing. as it is the great CO_2 source/sink that keeps CO_2 levels roughly stable. It is assumed that it takes a very long time for CO_2 absorbed in the warmer surface waters to be transported to the colder waters underneath and/or biologically or chemically sequestered, but I’m not sure how much experimental evidence there is for the rates that they assign. It is a problem of the same sort as plagues the GCMs (and indeed, is an implicit plaguey component of the GCMs). If you assume that you know what is going on, you can probably find a model that works decently because CO_2 is monotonically and smoothly increasing, so that many systems of ODEs describing CO_2 uptake and release can reproduce the base shape of the increase within reasonable ranges of their parameters. But the lack of uniqueness or even similarity of the models that can reproduce the observations, and the very different interpretations of the important physics and chemistry of those models, complicate the confirmation or rejection of any of them.
rgb

This is a little O/T, but every time I have asked an AGW believer what they think the optimum range for CO2 in the atmosphere is they have ducked it. They want to reduce CO2 levels, but they have no idea to what.
My understanding (as an ecologist) is that below 220ppm a slow-down in plant growth is significantly noticeable and below 150ppm most plants stop growing.

John Finn

RHS says:
January 2, 2013 at 11:39 am
Wasn’t the CO2 lifetime in the atmosphere at 100 years dropped/debunked to something closer 5, maybe 10?

No. There is, however, a great deal of confusion on this issue. It is true that the average lifetime of an individual molecule of CO2 in the atmosphere is about 5 or so years but that is not is not really the point of interest. The key statistic is the time taken for the atmospheric CO2 concentration to return to a previous level following a ‘pulse’ of increased CO2 such as that we have seen over the past 100 years or so. The basic relevant question is: how long would it take for CO2 concentrations to return to pre-industrial levels (280 ppm) if human contributions ceased.
Peter Dietze provides a reasonable estimate on the John Daly site. He finds the half lifetime of the pulse is ~38 years and that around 37% would remain in the atmosphere after 55 years. Theoretically, some of the added CO2 (see ** below) could still be present after 100 or even 200 years but this will only be a few ppm above the pre-industrial ‘equilibrium’ level.
** the “added CO2” won’t necessarily be human produced CO2. It may well be naturally emitted CO2 which hasn’t been re-sequestered because the natural uptake limit has been ‘satisfied’ by the human (+ natural) contribution.

Sean

Impossible…the UN has already declared that the sun has nothing to do with climate.

Doug Huffman

“As usual, people are willing to paper over the obvious discrepancies to support whatever cause they adhere to. (Dr. Svalgaard) Epistemologists that I read note the post-modern conception of logic as arguing from the conclusion to the supporting premises only.

mpainter

lsvalgaard says: January 2, 2013 at 11:59 am
=======================
So how reliable is 10 Be as a proxy?

mpainter says:
January 2, 2013 at 12:38 pm
So how reliable is 10 Be as a proxy?
10Be is a reliable proxy for the combined effect of the Earth’s magnetic field, Climate [atmospheric circulation], and Solar Activity. Separating the three sources is very hard. Many more ice cores from different locations may be needed. Another problem is that the theoretical underpinning for turning cosmic ray modulation into solar activity is on shaky ground. On danger of being too technical, the so-called ‘modulation parameter’ is computed based on an assumption we know is wrong, namely that the solar wind is spherical symmetric [i.e. the same in all directions from the sun]. This assumption may be reasonable at high solar activity [e.g. at solar maximum], but is demonstrably wrong at low activity, e.g. http://www.leif.org/research/A%20View%20of%20Solar%20Magnetic%20Fields,%20the%20Solar%20Corona,%20and%20the%20Solar%20Wind%20in%20Three%20Dimensions.pdf

Doug Huffman says:
January 2, 2013 at 12:37 pm
Epistemologists that I read note the post-modern conception of logic as arguing from the conclusion to the supporting premises only.
and even accepting conflicting premises as being equally valid…

TerryS

Re: rgbatduke
There is a problem with the bern model and that is CO2 mixing. The model assumes that CO2 is well mixed to begin with (no problem with that), but from then on there is no mixing of CO2 whatsoever. According to model the CO2 stays with whatever sink it happens to be at at the start. This leads to the ridiculous situation whereby 13.7% is supposed to remain in the atmosphere forever. (see http://unfccc.int/resource/brazil/carbon.html).

To get good measurements one would have to do something like inject a huge bolus of CO_2 into the atmosphere all at once and then watch how long it takes to decay back to quasi-equilibrium

Everything you need to know is already there. You know approximately how much CO2 enters the atmosphere from natural sources every year (about 770Gt), and what the equilibrium point is (278ppm or 2173Gt). From these two numbers you can calculate the half life:
2173 * ln(2)/770 = 2 years.
Of course the 2 year half life will be affected by temperature and probably many other factors but it shouldn’t vary much from the 2 years.
One final point, if you use the equations from the bern model to calculate how much CO2 is left after 1 year and then feed that back into the equations as a starting point (in other words remix the CO2 every year) you get a half life of about 6 years.

Tom in Florida

Looking at the scale, are we really talking about a difference of just over 1 w/m2?

Tom in Florida says:
January 2, 2013 at 1:01 pm
Looking at the scale, are we really talking about a difference of just over 1 w/m2?
Yes, but remember that the faithful invoke an unknown mechanism to amplify the impact of that tiny difference by ten times in their attempts to make it fit the observed temperature fluctuations.

Gail COmbs

fretslider says:
January 2, 2013 at 12:17 pm
This is a little O/T, but every time I have asked an AGW believer what they think the optimum range for CO2 in the atmosphere is they have ducked it. They want to reduce CO2 levels, but they have no idea to what.
My understanding (as an ecologist) is that below 220ppm a slow-down in plant growth is significantly noticeable and below 150ppm most plants stop growing.
>>>>>>>>>>>>>>>>>>>>>>>>
Yes that is certainly the fly in the ointment the zealots try to ignore. Check out the paper: Carbon starvation in glacial trees recovered from the La Brea tar pits, southern California. and Chemical Laws for Distribution of CO2 in Nature

…if the water temperature increases, the water cannot keep as much CO2 in solution, resulting in CO2 degassing from the water to the atmosphere. According to Takahashi (1961) heating of sea water by 1 degree C will increase the partial pressure of atmospheric CO2by 12.5 ppmv during upwelling of deep water. For example 12 degrees C warming of the Benguela Current should increase the atmospheric CO2 concentration by 150 ppmv.
Volk & Liu (1988) modelled the CO2 flux between atmosphere and oceans, and concluded that approximately 70% of the flux was governed by this “thermal solubility pump”, while approximately 30% was governed by the organic nutrient “biological pump”. Faure (1990) estimated that ca. 4000 GT (Gigatonnes = billion metric tonnes) of CO2 is transferred by degassing of the ocean via the atmosphere to the continental biosphere from the end of a glaciation to an interglacial stage….

Given the earth is cooling over the long term not warming, I much prefer more CO2 to less CO2.
The fact we can now grow twice the wheat or corn on the same acreage is a CO2 benefit that should normally be greeted with glee instead of squirming to negate it.

more soylent green!

If you want to be taken seriously, don’t name your model SATIRE.

RHS says:
January 2, 2013 at 11:39 am
Wasn’t the CO2 lifetime in the atmosphere at 100 years dropped/debunked to something closer 5, maybe 10?
Two different lifetimes: the around 5 years lifetime is the average time that a CO2 molecule of any origin resides in the atmosphere before being exchanged with a CO2 from another reservoir (mainly oceans and vegetation). The 100 years (Bern model for the bulk of CO2) is how long it takes for some extra CO2, whatever its origin, above equilibrium to return halfway back to equilibrium. In the first case, the throughput of CO2 is important: some 150 GtC/year of CO2 is exchanged back and forth between the oceans/vegetation at one side and the atmosphere. Partly continuous (warm equatorial upwelling, cold polar downwelling), partly seasonal in the mid-latitude oceans and vegetation. That gives a turnover of 150/800 or ~20%/year or a residence time for any CO2 molecule of about 5 years. In the second case, the current sink rate is ~4 GtC/year, partly into vegetation, partly into the (deep) oceans. That is caused by an increased pressure of CO2, currently some 210 GtC (100 ppmv) above the long term temperature dictated equilibrium. That gives an e-fold time of 210/4 or 52.5 years or a half life time of the extra CO2 of ~40 years. Quite a difference with the 5 years residence time or the 100 years from the Bern model. The latter includes saturation of the deep oceans. That may be right when we reach 3000-5000 GtC releases (currently we are at 370 GtC accumulated fossil fuel use). But there are no signs that the deep oceans are saturated and certainly no signs that vegetation growth is saturated or will be saturated in the foreseeable future…

Stephen Richards

Stevo says:
January 2, 2013 at 11:35 am
The case against AGW just gets stronger and stronger. Love it.
This does nothing to negate the case for AGW. It merely suggest that there is a noticable solar influence on global temps, maybe.

FerdiEgb

TerryS says:
January 2, 2013 at 1:00 pm
You know approximately how much CO2 enters the atmosphere from natural sources every year (about 770Gt), and what the equilibrium point is (278ppm or 2173Gt). From these two numbers you can calculate the half life: 2173 * ln(2)/770 = 2 years.
Sorry, but you are confusing the inflow with the difference between actual and equilibrium CO2 levels. It is that difference which is the driving force to remove extra CO2 out of the atmosphere. That is currently about 100 ppmv or about 210 GtC. The natural inflow is more than compensated by the natural outflow, only the difference between the two is important, which is only 4 GtC more sink than source, that is caused by the 210 GtC extra in the atmosphere. So the half life time is ~40 years…

The solar climate link is more likely in the higher latitudes since the strength of both the Earth’s and the solar induced magnetic fields changes are strongest there. Result of the combined effect is: the temperature natural variability
http://www.vukcevic.talktalk.net/GYCR.htm

LKMiller

Gail COmbs says:
January 2, 2013 at 1:09 pm
“…The fact we can now grow twice the wheat or corn on the same acreage is a CO2 benefit that should normally be greeted with glee instead of squirming to negate it.”
I have seen statements such as the above occur occasionally on WUWT posts over the past few years (sometimes also applied to tree growth rates), and believe it necessary to challenge the not-so-veiled implication that, were it not for increasing atmospheric CO2 concentrations, we would not be enjoying the significant increases in crop and forest production rates of the past 80-90 years.
My apologies up front if this is not what you mean to say. However, it is provable that increased per acre production rates (food crops and timber) are due more to decades of applied plant and tree breeding, and to improved crop and silvi-culture. If we take just corn as an example, the number of ears per plant, ear size, and number of kernels per ear haven’t changed much since the 1920’s. However, breeding and selection programs have drastically changed the architecture of the corn plant, such that farmers now plant at nearly 3X the density their grandfathers did.
For trees, developed western economies have had intensive applied breeding programs for nearly 60 years. In the US alone, tree breeding programs in loblolly pine and Douglas-fir are responsible for significantly increased rates of growth.
We know that CO2 is used to enhance growth in commercial greenhouses, and controlled studies have shown that higher CO2 increases tree growth. However, most of the increases of the last 80+ years are due to breeding and culture, not CO2.

John West

Doug Proctor says:
“To date, there are no unique TSI or (as I suspect) heat redistribution or other, non-CO2 signs we can point to for the skeptical defense.
What? How about the missing hot spot? How about a inexplicable warming pause while CO2 increases? How about stratospheric cooling pause? How about ocean heat content increase pattern not matching the CO2 increases causing warming pattern? How about the warming pattern matching PDO cycles? How about warming matching solar spectral variation patterns (not just TSI, i.e.: Bond Cycles)?

Stevo

Stephen Richards says:
January 2, 2013 at 1:37 pm
This does nothing to negate the case for AGW. It merely suggest that there is a noticable solar influence on global temps, maybe.
I’m happy to call it as another nail in the coffin. !!

Quinn the Eskimo

Ferdinand – How does a molecule of CO2 know whether it is governed by the first case or the second?

TomRude

Leif writes: “Yes, but remember that the faithful invoke an unknown mechanism to amplify the impact of that tiny difference by ten times in their attempts to make it fit the observed temperature fluctuations.”
1) Leif, do we observe tiny difference in solar output during a winter for instance?
2) Because for a given winter, we observe certain synchronous periods of extreme cold ejections over the entire hemisphere followed by periods of relatively milder cold air coming from the pole, then back again to strong cold. It cannot be related to planetary position nor if I understand Leif’s point correctly, to solar output difference. So what mechanism is responsible for these synchronous short term fluctuations in cold air polar ejections?
Thanks

Gail Combs

Tom in Florida says:
January 2, 2013 at 1:01 pm
Looking at the scale, are we really talking about a difference of just over 1 w/m2?
>>>>>>>>>>>>>>>>>>>>>
There is a lot of sleight of hand going on in the climate debates.
Paraphrased from WUWT link
Take a look at the radiative forcing table from the IPCC reports, where the explanatory variables that get included in the IPCC computer models are laid out. You will see that the only solar forcing effect listed is “solar irradiance.” In AR5 this table is on page 8-39:
The Graph
Also take a look at the water forcing effect compared to that of CO2. In actuality the forcing of water is rolled into that of CO2 because of the assumption that
1. CO2 causes warming.
2. Warming causes increased water vapor
3. Water vapor causes more warming.
But the evidence shows this is not what is happening. A graph and a WUWT link
Then look at CO2 vs Solar. Again there is sleight of hand. Look at these graphs:
The relative strength of the energy of a specific wavelength from the sun vs earthshine: graph 1
The absorption of various wavelengths of sun energy at TOA, surface and under the ocean: graph 2
A closer view of the energy absorbed by the ocean at various depths: graph 3
Oceans cover 70% of the earth’s surface and earthshine reflected back to earth by CO2 has no real effect on the ocean heat content. Ocean Heat Content from 1955 to 2011 (Joules 10^22) graph 4
The other bit of information that is left out is although TSI may remain relatively constant over the short term the distribution of energy among various wavelengths does not and neither do other attributes of the sun. Despite claims to the contrary science really has no idea what the various changes might cause.
The fact we see all sorts of papers about the sun’s effect on the earth from Alexander Ruzmaikin, Joan Feynman and Yuk Yung’s Does the Nile reflect solar variability? and The pattern of northern hemisphere surface air temperature during prolonged periods of low solar output (“We show that the reconstructed sensitivity of the sea level temperature to long term solar forcing in the Northern Hemisphere is in very good agreement with the empirical temperature pattern corresponding to changes of the North Annular Mode (NAM). This implies that long-term variations of solar output affect climate predominantly through the NAM that extends throughout the stratosphere and troposphere.)
To the “Shiva Hypothesis” show just how active this area of research really is despite the IPCC’s efforts to shut down this avenue of research with TSI is constant, nothing to see here move along, CO2 explains Climate Change and YOU are to blame.

vukcevic says:
January 2, 2013 at 2:01 pm
The solar climate link is more likely in the higher latitudes since the strength of both the Earth’s and the solar induced magnetic fields changes are strongest there. Result of the combined effect is: the temperature natural variability
None of these have anything to do with the climate. There is no historical data to compare and the polar regions are but a very small part of the globe.

John West

lsvalgaard says
“Yes, but remember that the faithful invoke an unknown mechanism to amplify the impact of that tiny difference by ten times in their attempts to make it fit the observed temperature fluctuations.”
The CO2 faithful just ignore that components of TSI can vary 10 times more than TSI itself. Varying the area under the curve is not the only way solar activity can effect climate, see Bond Cycles.
We’re all about to find out one way or the other anyway. Obviously, if CO2 dominates then global average temperature will resume it’s rise, if solar spectral variation that sunspots proxy dominate then global average temperatures will begin to decline, but if neither dominates (ie: close to 50/50) then global average temperatures will continue this sideways trend.

Neil

“What I find interesting is that the 1.5 W/m2 isn’t far from the value for CO2 forcing”
Just because something is in the same unit it doesn’t mean it is the same thing. The radiative forcing associated with a TSI change of 1.5 W/m2 is 1.5*0.7/4 = 0.26 W/m2 once you account for geometry and the albedo.
Not so interesting perhaps?

John West says:
January 2, 2013 at 2:06 pm
How about warming matching solar spectral variation patterns (not just TSI, i.e.: Bond Cycles)?
Yeah, how about them? The spectral variation has only been measured [with large error bars] for about a decade, and Bond Cycles don’t exist.

lsvalgaard says: Yes, but remember that the faithful invoke an unknown mechanism to amplify the impact of that tiny difference by ten times in their attempts to make it fit the observed temperature fluctuations.
1. Hardly. Per the IPCC formula, which includes alleged [but false] positive feedback from water vapor, the alleged forcing from CO2 + feedbacks from preindustrial times to the end of the 20th century is 5.35*ln(370/290) = 1.3 Wm-2 at the top of the atmosphere or about 1.3/3.7 = 0.35 Wm-2 at the Earth surface. The above paper is reconstructing solar activity at the Earth surface and shows a change of ~1.2 Wm-2 over the same period, even without any amplification.
2. What is the “unknown mechanism” that the faithful believers of the “Solar activity doesn’t change” religion you subscribe to that accounts for the climate change shown in the 1st paper above and countless others showing a link between solar activity and climate change over relatively short timescales?

“lsvalgaard says:
January 2, 2013 at 1:08 pm
Tom in Florida says:
January 2, 2013 at 1:01 pm
Looking at the scale, are we really talking about a difference of just over 1 w/m2?
Yes, but remember that the faithful invoke an unknown mechanism to amplify the impact of that tiny difference by ten times in their attempts to make it fit the observed temperature fluctuations.”
Yes well the unknown mechanism is not TSI but some of the obvious known affecting solar outputs of such as, proton flux, UV, magnetic, etc with react with ozone, upper level areas, earths magnetic structure, electric fields. pressure patterns, jetsreams, yes unknown, but plenty of papers setting out the effects that occur…and if they regularly occur, then they are real, njo matter if we know the real connections or not. If the solar different outputs change andn the weather-climate changes at the same time always then there is a true connection, whether we know it or not yet.
If we waited for all things to be fully proven, then mankind would never have advanced. We used fire, elecrocity, bread mold,, gravity, etc etc etc well before we really understood them. I use solar outputs every day and month and year to predict weather, together with the ussual oceans etc, and they work every time, so I know that the solar weather/climate connections are real. The mechanisms, well they may be many years off finding,, but if I wait that long I will never get to use them all very successfully. So why wait, if it works, it works, if I said they did not I would be lying.
People get so hung up on having to know exactly how something works. If it works well and consitently then use it. The truth will eventually come out and be found. We still are only scratching the surface of all knowledge and science.

TomRude says:
January 2, 2013 at 2:18 pm
1) Leif, do we observe tiny difference in solar output during a winter for instance?
Weather is not climate. And yes there are those tiny differences on top of a huge variation [70 times as large] due to the variation of the distance to the Sun. We are closest in January and thus gets the most then.
Hockey Schtick says:
January 2, 2013 at 2:32 pm
The above paper is reconstructing solar activity at the Earth surface and shows a change of ~1.2 Wm-2 over the same period, even without any amplification.
and that 1.2 W/m2 yields a temperature of less than 0.1 degree. That I can endorse.
countless others showing a link between solar activity and climate change over relatively short timescales?
Equally many invoke the great thermal inertia of the oceans to explain why there are no short time scales involved.
Ian Holton says:
January 2, 2013 at 2:34 pm
Yes well the unknown mechanism is not TSI but some of the obvious known affecting solar outputs of such as, proton flux, UV, magnetic, etc with react with ozone, upper level areas, earths magnetic structure, electric fields…
All of which vary the rhythm of TSI.
I use solar outputs every day and month and year to predict weather,
Some people consult their daily horoscope to decide what to do or expect.

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Stevo says:
January 2, 2013 at 2:07 pm
Stephen Richards says:
January 2, 2013 at 1:37 pm
This does nothing to negate the case for AGW. It merely suggest that there is a noticable solar influence on global temps, maybe.
I’m happy to call it as another nail in the coffin. !!
======================
Well, to a simple seafarer, it looks like someone thinks that changes in the (relative) location, behaviour, and temperature of the Sun may – may, I said – have an effect on the Earth’s temperature; [Average, mean/mode/median – howsoever arrived at).
I think they might be right.
I mean – it’s nearly a million miles across, and is at over five thousand Centigrade.
[Argument from incredulity?] – no, not so; have you noticed the difference between summer and winter warmth?
Ahhhhhhhhhhhhhhh –
Does the Sun alone affect our climate?
Probably not.
Not alone, I think,.
It does affect it, I guess/understand, but – alone – I think not!!!
Arrangement of the continents; mountain range elevation; distribution of shallow seas; albedo [with/without clouds – and what affects cloud cover? Huh?]; orbital parameters; and vulcanism all seem likely to cause local, regional and – possibly – global climate effects.
I believe that there are many other variables that affect local temperaures [and so, over decades and centuries and millenia – our climate].
We could paint all our roofs white.
Car roofs, too, I suppose.
And umbrellas – and hats ( and line them with tin foil?).
A possible reduction in UHI effects.
But there is a lot more to this climate lark . . .
For what it’s worth – not being a crimatologist [a truly magnificent neologism!] – I suggest
We don’t really know what affects climate – WUWT has a list of things that may [and I bet it’s not exhaustive for 2053!] – we know some of the variables [possibly most of them], but mostly do not fully understand their effect [short, medium and long term – even taken singly] on our planet’s climate. Even taken singly.
Now I think that interaction betwen any two factors is not really understood, generally. And we have – what? – scores? A very, very, complex stew here I fear.
I would like a little more warmth in the next twenty years. I fear more cooling.
And I don’t have a blind idea what to expect.

lsvalgaard says:
January 2, 2013 at 2:23 pm
vukcevic says:
January 2, 2013 at 2:01 pm
The solar climate link is more likely in the higher latitudes since the strength of both the Earth’s and the solar induced magnetic fields changes are strongest there. Result of the combined effect is: the temperature natural variability
http://www.vukcevic.talktalk.net/GYCR.htm
None of these have anything to do with the climate. There is no historical data to compare and the polar regions are but a very small part of the globe.
———————————————————
Have you heard of polar amplification, main contributor to the GW ?
http://www.vukcevic.talktalk.net/GTSD.jpg
NASA: Temperature pattern is a manifestation of “Arctic Amplification”, which is characterized by temperature increases 1.5°C greater than (more than double) the increases at lower latitudes (Overland et al., 2011; Stroeve et al., 2012).

John West

lsvalgaard says:
“The spectral variation has only been measured [with large error bars] for about a decade”
So, you’ve excluded it as a potential cause or even a significant contributor of recent warming (that happened over a decade ago) based on this paltry data?

DocMartyn

rgbatduke, we did the bolus addition of 14C using the atmospheric H-Bomb tests. The pseudo-first order decay is approximately a decade. The only fly in the ointment is that the steady state level of 14C changes with cosmic ray flux, means that natural abundance is hard to calculate.
The models suck, mostly because they are exquisitely sensitive to the rate at which 14C fixed by plankton falls to the bottom of the sea bed as organic particulates and then returns to the surface as 14C gasses,CO2 and CH4, the latter is a pig to model as {CH4} is inversly proportional to [O2].
One would expect, a prior, that if cosmic rays had a large impact on the climate then one could look for the relative 14C abundance in tree rings vs. tree ring width.

Steve Keohane

Overlaying the 11.5K year TSI reconstruction, Fig. 11, on the GISP2 temperature reconstruction doesn’t do much for me. Didn’t see an obvious offset in x-axis either.
http://i49.tinypic.com/oji4b7.jpg

Thanks for that reference, Gail
fret

lsvalgaard says: Hockey Schtick says: January 2, 2013 at 2:32 pm
The above paper is reconstructing solar activity at the Earth surface and shows a change of ~1.2 Wm-2 over the same period, even without any amplification.
and that 1.2 W/m2 yields a temperature of less than 0.1 degree. That I can endorse.

1. According to the IPCC, a doubling of CO2 results in an increase of 3.7 Wm-2 at the TOA and about 1 Wm-2 at the surface, allegedly resulting in 3C global warming at the surface. So which is it Leif:
a. An increase of [1.2 Wm-2]/4 = 0.3 Wm-2 at the surface causes an increase of surface temperature of << 0.1 degree as you claim
or
b. An increase of 0.3 W/m2 at the surface causes an increase of surface temperature of ~ 0.9 C
2. I see you prudently avoided answering my question #2 above, so I'll restate it again:
What is the “unknown mechanism” that the faithful believers of the “Solar activity doesn’t change” religion you subscribe to that accounts for the climate change shown in the 1st paper above and countless others showing a link between solar activity and climate change over relatively short timescales? So Leif, what is the “unknown mechanism”?
3. Leif also says:
countless others showing a link between solar activity and climate change over relatively short timescales?
Equally many invoke the great thermal inertia of the oceans to explain why there are no short time scales involved.

a. Only shortwave solar radiation can heat the oceans, not changes in IR from GHGs
http://hockeyschtick.blogspot.com/2012/09/realclimate-admits-doubling-co2-could.html
b. Many papers have demonstrated a link between solar activity and ocean oscillations, which brings us back to question #2 above.

vukcevic says:
January 2, 2013 at 3:09 pm
Have you heard of polar amplification, main contributor to the GW ?
Which has nothing to do with the cycles you are peddling. There is still no data from the polar regions to determine any cycles.
NASA: Temperature pattern is a manifestation of “Arctic Amplification”, which is characterized by temperature increases 1.5°C greater than (more than double) the increases at lower latitudes
The ‘effect’ goes the wrong way. You want to polar regions to control the rest, but clearly they do not.
John West says:
January 2, 2013 at 3:18 pm
So, you’ve excluded it as a potential cause or even a significant contributor of recent warming (that happened over a decade ago) based on this paltry data?
Would be base policy on paltry data?

lsvalgaard says:
January 2, 2013 at 2:47 pm
“Hockey Schtick says:
January 2, 2013 at 2:32 pm
The above paper is reconstructing solar activity at the Earth surface and shows a change of ~1.2 Wm-2 over the same period, even without any amplification.
and that 1.2 W/m2 yields a temperature of less than 0.1 degree. That I can endorse.”
With a natural trend in place of 0.5-0.6º C per century since the LIA, this extra 1.2 Wm-2 gives us the 0.7º C for the last hundred years.
Its the Sun, stupid!

TomRude

Thank you Leif. So indeed we observe during a winter tiny differences of output. I noticed you did not comment on my point #2…

TomRude

BTW Leif, weather is not climate except that climate expresses itself through the succession of weather events over the years. Thus explaining these weather variations within a season is key in deconstructing the various elements at work rather than plastering CO2 everywhere.

Gail Combs

LKMiller says:
January 2, 2013 at 2:01 pm
…..I have seen statements such as the above occur occasionally on WUWT posts over the past few years (sometimes also applied to tree growth rates), and believe it necessary to challenge the not-so-veiled implication that, were it not for increasing atmospheric CO2 concentrations, we would not be enjoying the significant increases in crop and forest production rates of the past 80-90 years…..
>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Response curve for C3 and C4 plants Graph Note Wigley (1983) claims a pre-industrial CO2 level of 270ppm.
Actually it is both. Given enough nutrients and water, CO2 is going to be the limiting factor in plant growth. That is why greenhouses use 1000 to 2000 ppm CO2 and air fans. C3 plants are much more sensitive to CO2 compared to C4 and C3 plants also become more drought resistant at higher levels of CO2. However remember carbon/petrochemical based products/energy is also responsible for the fertilizer, herbicides, pesticides, tractors and other machinery that went into that increase in harvest so it is CO2 coming and going. (Grin) The increase in drought resistance would play a part in the yields of non-irrigated fields and fields at the upper northern limit in the Northern hemisphere.Wind (air circulation) will also have a significant effect.
photo and link
The Earth’s biosphere is booming, data suggests that CO2 is the cause, part 2
CO2 depletion

As CO2 is a critical component of growth, plants in environments with inadequate CO2 levels – below 200 PPM – will cease to grow or produce. …Plants use all of the CO2 around their leaves within a few minutes leaving the air around them CO2 deficient. Without air circulation and ventilation the plant’s stomata are stifled and plant growth stunted…. https://greenair.com/old/pdf/efs/co2-efs.pdf

Plant photosynthetic activity can reduce the CO2 within the plant canopy to between 200 and 250 ppm… I observed a 50 ppm drop in within a tomato plant canopy just a few minutes after direct sunlight at dawn entered a green house (Harper et al 1979) … photosynthesis can be halted when CO2 concentration aproaches 200 ppm… (Morgan 2003) Carbon dioxide is heavier than air and does not easily mix into the greenhouse atmosphere by diffusion… Source

EXPERIMENTS: Percent Dry Weight (Biomass) Increases for 300, 600 and 900 ppm Increases in the Air’s CO2 Concentration

About 430 observations of the yields of 37 plant species grown with CO2 enrichment increased agricultural weight yields by 36%. Additional analysis of 81 experiments which had controlled CO2 concentrations showed that yields will probably increase by 33% with a doubling of CO2 concentration. Another 46 observations of the effects of CO2 enrichment on transpiration were extracted and averaged. These data showed that a doubling of CO2 could reduce transpiration by 34%, which combined with the yield increase, indicates that water use efficiency may double.
Kimball,B.A. and Idso, S.B. 1983. “Increasing atmospheric CO2 : effects on crop yield, water use and climate. Agric. Water Manag., 7:55-72

video

John West

Anthony, I don’t know why you just don’t tell people the truth!
The real reason for 20th century global warming is actually CCF (Cricket Chirp Frequency). Yes, CCF slightly lags temperature but this is merely because CCF is both a feedback and a forcing. You get a little bit of warming and that increases CCF, which increases temperature, which increases CCF and so on and so forth. Luckily for us there’s a limit to how fast and how long crickets chirp or they would have boiled away the oceans long ago. Also, different species of crickets have different chirp frequencies as well as varying stamina and season (as in mating, etc.) frequency variations. For example, the snowy tree cricket of the north has a slower chirp frequency than his more southerly cousins. This is actually why we have daily, seasonal, and geographic temperature variations; it has absolutely nothing to do with the Sun or Earth’s rotation or tilt or any of that fictional stuff they teach in school, it’s simply the average CCF of the crickets in the area. The 20th century simply saw an expansion of higher frequency chirping crickets. To combat this all we have to do is institute programs that retards expansion of faster chirping crickets and aids expansion of slower chirping crickets. But we have to be careful, slow chirping cricket population explosions cause ice ages.
http://www.dartmouth.edu/~genchem/0102/spring/6winn/cricket.html
In order to develop and implement the best possible program before it’s too late I’ll need funding right away.
[Just in case ….. /sarc]
In case you haven’t been following the “debate” long, the standard CS (BS) answer to why CO2 lags temperature by ~800 years in the ice core records is basically because CO2 is both a feedback and a forcing. You get a little bit of warming and that increases CO2, which increases temperature, which increases CO2 and so on and so forth. Apparently, that explanation works for CO2 or CCF. Actually, it works a little better for CCF, at least CCF has a mechanism to keep it from going to runaway global warming.

John West

lsvalgaard says:

John West says:
“So, you’ve excluded it as a potential cause or even a significant contributor of recent warming (that happened over a decade ago) based on this paltry data?”

”Would be base policy on paltry data?”
Perhaps for politicians/lawyers it’s ok to exclude possibilities just on the basis of not having enough evidence to draw a conclusion, but not scientists. As skeptical as I am of CO2 induced dangerous climate change, I still haven’t excluded it even though the weight of the evidence is against it at the moment, conclusive evidence one way or the other isn’t in yet.