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More on sun-climate relations

Filed under: — rasmus @ 9 March 2010

Four new papers discuss the relatiosnhip between solar activity and climate: one by Judith Lean (2010) in WIREs Climate Change, a GRL paper by Calogovic et al. (2010), Kulmala et al. (2010), and an on-line preprint by Feulner and Rahmstorf (2010). They all look at different aspects of how changes in solar activity may influence our climate.

The paper by Judith Lean (2010) has the character of a review article, summarizing past studies on the relationship between solar forcing and climate. The main message from her article is that the solar forcing probably plays a modest role for the global warming over the last 100 years (10% or less). It’s a nice overview, but I miss treatment of uncertainties.

Her analysis is based on the HadCRUT3 data, and I wonder if she would get similar results if she chose the GISTEMP or NCDC instead. The choice may in particular be relevant for the discussion of the temperatures after 1998.

Personally, I regard the data on solar activity before 1900 as quite uncertain too. The reason is that there are strange things happening to the solar cycle length in the shift from the 19th to the 20th century. Hence, any analysis based on the past centuries is uncertain because of suspect data quality in the early part of the record. Lean mentions that proxy-based records are uncertain, however.

Another source of uncertainty stems from the analysis itself – a regression analysis with chaotic data can easily yield misleading results. Gavin and I showed in a recent paper that multiple regression can produce strange results when applied to the global mean temperature and a number of forcings.

In other words, I think the reader may get the wrong impression from Lean (2010) that the link between solar activity and climate is better established than the data and methods suggest. Especially when she discusses forecasts for the near future (eg. for year 2014) – I fear that such a discussion can be misinterpreted and misused. However, that’s my view, and it does not necessarily mean that her paper is incorrect – quite the opposite, I think her main conclusions are sound (Her estimate of the solar contribution to the global warming over past century – 10% or less – is in good agreement with the figure Gavin and I got in our analysis).

The positive side is that the paper is probably clearer and more accessible without all these caveats. I also think she makes an interesting point when she discusses ‘fundamental puzzles’ associated with claims of strong solar role in terms of the past warming. She puts this into the context of climate sensitivity, arguing that it would imply that Earth’s climate be insensitive to well-measured increases in GHG concentrations and simultaneously excessively sensitive to poorly known solar brightness changes. Furthermore, Lean argues that it would also require that the Sun’s brightness increased more in the past century than at any time in the past millennium – a situation not readily supported by observations.

The paper of Calogovic et al. (2010) is a follow-up of a recent paper by Svensmark et al. (2009), looking into the claim that the cloud water content drops after a Forbush event. Their work involved estimating cosmic ray fluxes for the whole planet, and comparing it to local cloud information derived from satellites. They concluded that the Forbush events had no detectable effect on the clouds.

Moreover, they also argued that the analysis of Svensmark et al. (2009) gave unreliable results since it included a Forbush event on January 20, 2005 which was accompanied by a strong solar proton event. However, they did not explain explicitly why such proton events would disturb the measurements, but referred to another study by Laken et al. (2009) in Geophysical Research Letter. Laken et. al. only discusses the proton events briefly, and refers to a study by Fluckiger et al. (2005), who state that “The cosmic ray ground level enhancement (GLE) on January 20, 2005 is ranked among the largest in years, with neutron monitor count rates increased by factors of more than 50”.

But there is no reference to proton events in Fluckiger et al. (2005), so I’m not convinced that proton events will invalidate the analysis of Svensmark et al. (2009). Perhaps I’m missing something? Anyway, this is only a minor detail, and the rest of the analysis of Calogovic et al. (2010) seems more convincing. Their conclusion is supported by Kulmala et al. (2010): “galactic cosmic rays appear to play a minor role for atmospheric aerosol formation events, and so for the connected aerosol-climate effects as well”. Kulmala’s group in Finland boasts many world-renowned aerosol physicists.

The study by Kulmala et al. (2010) was based on near-ground measurements of aerosols, magnetic field, cosmic rays, sunlight intensity (solar radiation), and ionization over a 13-year long period (~1 solar cycle). They also used airborne Neutral cluster and Air Ion Spectrometer, LIDAR and Forward Scattering Spectrometer Probe measurements. They failed to detect any correlation between cosmic ray ionization intensity and atmospheric aerosol formation.

Feulner and Rahmstorf address a speculation stated by Lean: the possibility of solar forcing countering anthropogenic global warming. Their paper examines the effect a solar grand minimum (low solar activity similar to that inferred for the Maunder Minimum) would have on the global mean temperature by 2100. By accounting for a corresponding reduction in forcing for the future in a climate model study, they conclude that the effect is negligible (less than 0.3K compared to 3.7 – 4.5K if the SRES A1b or A2 emission scenarios were assumed).

So what can we learn from these articles? What we see is how science often works – increases in knowledge by increments and independent studies re-affirming previous findings, namely that changes in the sun play a minor role in climate change on decadal to centennial scales. After all, 2009 was the second-warmest year on record, and by far the warmest in the southern hemisphere, despite the record solar minimum. The solar signal for the past 25 years is not just small but negative (i.e. cooling), but this has not noticeably slowed down global warming. But there are also many unknowns remaining, and the largest uncertainties concern clouds, cloud physics, and their impact on climate. In this sense, I find it ironic that some people still rely on the cosmic rays argument as their strongest argument against AGW – it does involve poorly known clouds physics!

192 Responses to “More on sun-climate relations”

  1. 151
    Tim Jones says:

    How much do ocean currents influence the perception of a warming climate? Is there information describing how warm and cool sea water gives off and absorbs heat in pulses? Is there information describing how many simultaneous patches of cool water make for a record of cooler SSTs? How much does an apparent lessening or accelerating of the rate of warming have to do with the interaction or appearance of warming and cooling ocean currents worldwide?

    We’ve seen how ENSO, sunspot cycles and stratospheric water vapor are all parts of natural variability that influence the record of surface temperatures. Do variabilities in ocean currents do so as well?

  2. 152
    J Gradie says:

    RE: (#127)[Response: Actually, this was written down over a century before the founding of the republic. – gavin]
    Thank you for the uplifting verse. How inspiring to glimpse the Renaissance vision whilst down in the weeds. Your wit is singular.

  3. 153
    flxible says:

    The current Canadian govt has long shown an inclination to allow other countries [read US] to carry the ball on many topics, explicitly citing the fact that the Canadian economy is so entwined with the US that all that can be done is follow their lead on anything that may have effects on it – economics just happens to be the area of “expertise” of the current Prime Minister – who also happens to be from Alberta, where tar sands are considered the driving force for all Canada.

    Of course, the PM also has made noise about demonstrating “sovereignty” in the Arctic and hasn’t put much funding there either.

  4. 154
    Ray Ladbury says:

    Actually, I think that given where Harper’s head is buried, he would be very uncomfortable if there were sand there, too.

  5. 155
    Septic Matthew says:

    111, Barton Paul Levenson: SM (75): You can not prove that what you don’t know does not matter.
    BPL: Surprisingly, sometimes you can do just that. It’s called analysis of variance, and if you can account for most of the variance in whatever you’re studying, you’re often (not always) in a position to say that, yes–WHATEVER the other influences are, known or unknown, their influence has to be minor.

    You need to review design of experiments. You can not prove with ANOVA on extant data that increasing the level of one of the factors, or adding an additional factor, would have no effect in a future experiment that has not yet been done. I refer you again to the physicists’ persistent claim that there was no source of energy sufficient to power continental drift. Only after the drift had been sufficiently demonstrated on the evidence did they look for a mechanism. It is one thing to aver that we know enough to act prudently, and another thing to aver that nothing can occur which would show us to be wrong in our current beliefs.

    143, Tim Jones: The destruction of rain forests and boreal forests world wide impact climate change in a big way. Pictures of the Amazon and palm tree plantations in Indonesia would be good…

    This is worthy of elaboration. Regrowth of N. American forests has sequestered a significant fraction of N. American industrial CO2. Although deforestation of Central and S. American forests continues, there is substantial regrowth of forests cut down in past decades, even in the Amazon where, in the 1970s, there were warnings that the deforested areas of the Amazon could not naturally reforest. If you buy CO2 credits you can (you have to be careful, caveat emptor) contribute to reforestation in Malaysia, Indonesia, Ecuador, Mexico and other places. One of the reasons that I am (regrettably) smug is that I pay for more CO2 sequestration than the CO2 I generate. The oil palm plantations are ambivalent: in some places they are an improvement, and in other places they are a degradation. EU nations can earn CO2 credits by investing in oil palm plantations.

  6. 156
    David B. Benson says:

    Septic Matthew (92) — Yes, it is tritely obviious that in 30 years we will have 20 more years of data. The point is we have vastly more than enough to understand that CO2 is a mian driver of climate during the instrumental period and into the future.

  7. 157
    MartinJB says:

    John (109) said:
    “Bearing in mind that for the last 200 recorded years Bangladesh has suffered catastrophic flooding, what makes you think reducing C02 will lessen that?

    Can you produce a study that shows that catastrophic, above normal (40% + land surface) flooding has occurred in the past 30 years compared to the previous 170?”

    You are kidding, right? Much of Bangladesh is a river delta, thus the flooding. Raise sea-levels by 1m and not only will a lot of land be permanently flooded, but salt-water incursion will cause additional agricultural land to be lost. And periodic flooding will get a lot worse. Do you really need a published paper to tell you this? Really?

    OK: Ali, A (1996). “Vulnerability of Bangladesh to climate change and sea level rise through tropical cyclones and storm surges”. Water, Air, & Soil Pollution 92 (1–2): 171–179.

  8. 158
    MartinJB says:

    Frank Giger (105):
    ‘“In addition to what Ray Ladbury says, have you thought about the political consequences of moving tens or hundreds of millions of people across national boundaries?”

    I had no idea there were that many people in Miami, or that they would suddenly migrate to Canada, Mexico, Peru, or any other country. Chances are more likely they’ll move to Orlando, Charlotte, Atlanta, or any number of places in the USA.’

    Wow. That’s a pretty narrow view. You do know that Miami’s not the only coastal city in the US vulnerable to rising sea level, right? And that there are other countries besides the US? Some of them will face rather worse impacts than the US and have a lot less capacity to mitigate those impacts. I very much doubt that my favorite example, Bangladesh, will be able to internally relocate most of those displaced by rising sea level and increased flooding. And the displaced of Bangladesh will be competing with the displaced of India and Burma. Won’t that be fun!

    I suspect that a lot of the countries that will face the most stress from a warming world are rather less culpable of causing global warming than the US. Maybe that doesn’t bother you. It bothers this American. Which is why I believe we have to lead in combating global warming. This is very much a moral issue. Our military and intelligence services also consider it a security issue.

  9. 159
    Brian Dodge says:

    “Germany has plan for an “integration contract” that new immigrants must sign. The contract lays out services and assistance available to immigrant communities and also explains what “we expect from them,” as Germany’s integration commissioner. Included among these expectations are knowledge of the German language and acceptance of gender equality and freedom of speech.
    Worldfocus special correspondent Martin Seemungal reported late last year on the rising Christian-Muslim tensions in Cologne, Germany — home to 120,000 Muslims — where the city’s first official mosque is in construction.”

    “The Netherlands today held municipal elections in hundreds of cities and towns across the country.
    The Freedom Party, a populist, anti-Muslim and anti-immigration party led by Geert Wilders, ran in just two of those elections.
    In one city, it came in first, and in the other city, the Hague, it came in second. The party wants to outlaw Muslim headscarves in Holland.
    What should be done about growing anti-immigrant and anti-Muslim sentiment in Europe?”

    “While many Americans can’t get jobs because of the recession, some are questioning giving jobs to illegal immigrants. Is it moral to give illegal immigrants jobs when Americans are vastly unemployed?”
    “… this comes at a time when 15 million Americans can’t find work. More than 32 million Americans now live on food stamps. This, he goes on, is a serious time for the nation and the question about illegal immigrants taking American jobs is one I’m number of people are asking these days.”
    “While the border states of Texas, California and Arizona are in critical financial shape, Mexico receives $25 billion in cash transfers when illegal immigrants send money back to Mexico from the United States.”
    “In addition to the problems of job competition, Wooldridge quotes Edwin Rubenstein, an economist, as saying American taxpayers give $346 billion annually for medication, education and incarceration of illegal immigrants and their children. So there is a drain on the economy from the social obligations.”

    “ROME, February 14, 2010 (AFP) – The stabbing death of an Egyptian youth in Milan sparked fresh anti-immigration calls Sunday that were immediately slammed by the left-wing opposition ahead of regional elections in Italy. Roberto Calderoli, a minister of the anti-immigration Northern League, said the incident ‘confirmed that we are paying for a mistaken ideology of the past… the policy of open doors for all.'”

    I welcome the prospect of new immigrants moving into my neighborhood, providing many opportunities for me to learn about new cuisine, social customs, and religious practices. However, I don’t think that the newly elected Raleigh NC anti diversity policy school board chairman, (who said into a microphone he didn’t know was live, “Here come the animals out of the cages” about pro diversity protesters at a recent meeting) will have the same feelings. If illegal immigration is already costing 371 billion dollars a year just in the US, It won’t be any cheaper than it will be fun.

    “The people, OTOH, will relocate. We can handle it – there is plenty of land.” Do we have plenty of jobs? Or water(5 of the last 10 years my town has had summer water restrictions)? Or roads? Or public transportation? Or housing? Or money to pay for the things we don’t have in surplus(like tolerance)?

  10. 160

    voteno (120): It is equally clear to anyone with a good understanding of heat transfer that increased CO2 in the atmosphere can not explain all global warming.

    BPL: No, just 76% of it over the last 130 years.

  11. 161
    Ray Ladbury says:

    While I agree that you can never eliminate the possibility of some new factor coming into play in the future, between what we know of current forcings (including CO2) and the paleoclimate data, the likelihood of this is effectively infinitesmal. There is no credible candidate, no suggestion of evidence for such a factor and considerable evidence to suggest such a factor is not extant.

    This is not a situation where we choose between action and inaction. Inaction is not an option. Chooding BAU is an action–not a viable action given the decreasing supply of fossil fuels–but an action nonetheless. The real choice is between creating a new energy infrastructure based on coal–only to have to create another infrastructure in less than 100 years when the coal runs out–or creating a new energy infrastructure that, once and for all, is sustainable. Climate change just tips the scales further. Time to choose.

    [cue Jeopardy Music]

  12. 162
    CM says:


    Thanks for the regular updates on solar-climate research. Much appreciated.

    Regarding Calogovic on Svensmark and “why such proton events would disturb the measurements”, Calogovic et al. also reference Mironova et al. (2008), who note:

    An increase of the concentration of sulfate or nitrate aerosol was found on the second day after the solar energetic particle event in the south magnetic pole region with the maximum penetration of anisotropic solar cosmic rays.

    But it’s still not clear how this by itself would affect the conclusions of Svensmark et al. (2009) who included the January 2005 event in their sample. If the solar proton event generated increased aerosols, that would — if anything — weaken Svensmark’s evidence by countering the postulated drop in aerosols after the Forbush GCR decrease, at least in the first days, wouldn’t it?

    Laken et al. say the event was unusual in other respects (structure of the Forbush decrease, atmospheric electric activity).

  13. 163

    Yes, SM, if something totally unforeseen and incredibly unlikely happened, it could account for more climate change variance in the future. For example, if the Martians started bombarding us for heat rays.

    Similarly, if the Venusians use their cold rays on us…

  14. 164
    Mike says:

    From Science News (March 11 2010):

    Magnetic flows cause sunspot lows, study shows

    Newly reported observations of gas flows on the solar surface may explain why the sun recently had such an extended case of the doldrums.

  15. 165
    Septic Matthew says:

    161, Ray Ladbury: This is not a situation where we choose between action and inaction.

    Perhaps you have not been reading my posts in which I advocate continued R&D and deployment of new energy technologies and CC&S. But if I lived on the Pacific Rim, also called the “Ring of Fire” for the active volcanoes, I would not rank AGW as the highest potential threat. Analogously, Bangladesh and the US Gulf Coast will continue to suffer from flooding and wind damage, so putting all their money into anti-AGW will be improvident; the US Midwest will always have alternations of tornadoes, droughts, floods and ice storms. I think that prudence requires what I have been calling “hedging bets”. In the meantime, recall that the IPCC AR4 predicted that with AGW fewer people will suffer increased water stress than suffer decreased water stress. Also, BAU is fairly dynamic: it produced the energy industry that we have today, and modern transportation. We don’t have BAU anyway: in response to fuel worries, even the Republican Bush administration started to support new energy, and the Democratic president Obama has stood by his pledge to support nuclear power.

    But back to science: While I agree that you can never eliminate the possibility of some new factor coming into play in the future, between what we know of current forcings (including CO2) and the paleoclimate data, the likelihood of this is effectively infinitesmal.

    You can only believe that after an anti-intellectual dismissal of Beenstock and Reingewertz (and a bunch of other work that uses integrated measures of solar activity.) There is lots of evidence that we don’t know some things (what caused pre 1970s warming and cooling; the increased energy stored by photosynthesis due to increased primary productivity in Boreal forests; the quantitative effects of the soot deposited on glaciers and arctic ice.) To say that we know that all those sources of ignorance will prove in the future to be negligible strikes me as premature at best. Historically, scientists have been corrected by new information repeatedly — it isn’t a rare occurrance, much less infinitesimal. A good history in particle physics is by Abraham Pais, titled “Inward Bound”. Right now, there is more observable gravitation in the observable universe than can be accounted for by the observable mass. And the Wegener example should not be forgotten.

  16. 166
    Septic Matthew says:

    Incidentally, I wrote to Beenstock and Reingewertz, requesting clarification of whether and when their paper will be published, and if in Nature.

  17. 167
    Ray Ladbury says:

    Septic, the Beenstock and Reingewerts paper is utter bullshit.

    It is what happens when people who don’t understand physics try to do physics.

    SM, the fact of the matter is that Wegener was wrong. His proposed mechanism for continental drift did not exist. It was not until we had learned a whole lot more about the high-pressure behavior of rock that we could develop a mechanism. So, I ask: what predictive capability was lost by geologists not accepting Wegener’s theory? None. How would the history of geology have been different? It wouldn’thave.

    Your argument seems to be: some scientist was wrong somewhere, sometime, so therefore I don’t have to believe any science if I don’t want to. Sounds suspiciously like the arguments coming out of the Discovery Institute, if you ask me. The situation in climate science is very different form that in cosmology or in geophysics–where we don’t have direct measurements of the entire system.

    By any reasonable measure, climate science has been very successful at explaining Earth’s climate. It also has an excellent track record of predictions. There is no evidence that there is anything significantly wrong with the models. And yet you are saying “Oh wait! We don’t know enough yet!” And you are proposing nothing constructive. That is at the very least an unscientific if not anti-scientific attitude.

  18. 168
    Septic Matthew says:

    Here’s a strange one, predicted temperature increases due to land-based wind turbines:

    It’s only one study, so it shouldn’t be believed on its own, but what if it’s true? Perhaps a moratorium on wind farms until we find out? I don’t know. I think nuclear power is probably better anyway, but I support wind farms in part because I don’t know what technologies will be best 5-10 years from now, and I don’t think any one should be forced out of the mix yet.

  19. 169
    Completely Fed Up says:

    “It’s only one study, so it shouldn’t be believed on its own, but what if it’s true? Perhaps a moratorium on wind farms until we find out? I don’t know. ”

    What if it isn’t? Should we stop replacement of expensive and polluting power generation with clean and local power generation just because a paper was wrong?

    And have a look at the stats. Compare the size of the affected area with the size and magnitude of, say, the Urban Heat Island.

    Do we level all our cities? I mean, we shouldn’t take that option out of the mix, should we…

    And check the “proofs” there. There is none. A Big Scary Number of power generation and no context. How much power per sq m? 10^12W/10^14m2 = 0.01W/sq m. Compare to the 4W that CO2 gives per doubling and this is 400x bigger. If 0.01W/sq m gives 0.15C rise, then the doubling of CO2 gives us 60C warming!!!

  20. 170
    dhogaza says:

    Ray Ladbury …

    SM, the fact of the matter is that Wegener was wrong.

    Harumph. Septic Matthew – I pointed out that Wegener was wrong when you first brought him up, why did you repeat it?

  21. 171

    RE #168–

    Highly preliminary.

    Also note that cooling over oceans is predicted, raising the possibility of balancing out heating by deploying turbines over oceans.

    That’s presuming this is valid at all.

  22. 172
    Hank Roberts says:

    SM, please try looking this stuff up for yourself first.
    Many of the “but what about this” items are longtime, familiar, brought here over and over by people who don’t think or check first. For example:

  23. 173
    Septic Matthew says:

    170, Ray Ladbury and dhogaza: Harumph. Septic Matthew – I pointed out that Wegener was wrong when you first brought him up, why did you repeat it?

    Wegener was right about the movement of the continents, but wrong on his guess of the source of the energy. Wegener did not originate the hypothesis of continental drift, but he began the systematization of the biological, geological, and paleontological evidence in support. Legions of scientists followed up on his work for generations, working despite the disrespect of physicists who asserted that the drift was impossible. “Drift” is misleading if you interpret it as “random”, but things can drift on currents, as the tecta do.

    169 Completely Fed Up and 172, Hank Roberts. I Can’t tell whether you are in agreement. You guys seem to be “antinomialists”, presuming to know the only complement or contradiction of a statement, and posing questions as extremes with no variation.

  24. 174
    ghost says:

    I hope this isn’t too far OT for this discussion. Last week’s news reported AccuWeather’s prediction of a “strong” Atlantic hurricane season with multiple U.S. landfalls. Part of the forecast’s basis appears to be a “rapidly weakening El Nino.” Does the RC readership happen to know if that (rapid weakening) is a generally accepted view of ENSO for 2010? (I’ve seen Indian forecasts accepting that this El Nino’s activity would persist until June, but I don’t know if that’s in the “normal” timeframe or if that implies ‘rapid weakening.’) I wonder if El Nino’s receding enough/soon enough to allow conditions favoring Atlantic landfall hurricane formation would change suppositions made in 2009 about 2010 global temps, or if it would make much difference.

  25. 175
    flxible says:

    ghost@174 – As someone who watches the NOAA El Nino advisories because it always has an effect on my left coast location, I don’t think “rapid weakening” is an accurate description, but I expect it’s weather influence to be much less significant by the end of April, and return to “neutral” looks to be about as expected by historical comparison [end June]. Effect on the hurricane season is another question for those on the wrong coast.

  26. 176
    Hank Roberts says:

    > SM
    > antinomialists

    No, I’m a proscholarist. I recommend you check out notions often found posted repeatedly on blogs. Compare what you find with Google and with Scholar.
    Make the minimum effort yourself to think. Assertions of ideas like windmills changing climate come back over and over. You can look them up.

  27. 177
    Tim Jones says:

    Re:175 flxible says: 13 March 2010 at 11:35 AM

    Much of hurricane development has to do with SSTs and wind shear. It’s too nice a day to do much of this, but, since you seem to have your ear to the ground regarding the consequences of the current El Niño, what do you see coming by way of hurricanes this Autumn? And then, are glt’s going to replicate or exceed what we saw in 1998 this summer?

  28. 178
    Septic Matthew says:

    176, Hank Roberts: . Assertions of ideas like windmills changing climate come back over and over.

    I cited a particular recent study, an addition to the scholarship.

  29. 179
    flxible says:

    TimJones – It’s what we up north call a “useable day” here too – after a couple months of mostly gray, EL Nino is releasing us from it’s grip :)

    I haven’t been watching ENSO in relation to hurricane activity, but I’m ready to be completely UNsuprised by the coming summer producing more record temps, including rising SST’s, which I suppose would mean the liklihood of increased hurricane activity or intensity – my view of the various climate associated weather events is that they will, and can only, “worsen”, and more rapidly as time is wasted by our “overlords”. For a view of ENSO and SST from the other side, Australia has a good report which may have more relevence to hurricane activity.

  30. 180
    Completely Fed Up says:

    SM: “I cited a particular recent study, an addition to the scholarship.”

    You didn’t approach it with skepticism, though, did you ***Septic Matthew***

  31. 181
    Completely Fed Up says:

    “You guys seem to be “antinomialists”, presuming to know the only complement or contradiction of a statement, and posing questions as extremes with no variation.

    Comment by Septic Matthew”

    Funny how you attribute THREE options from me as the “only complement or contradiction”.

    Can’t count?

  32. 182
    J Bowers says:

    127 Frank Giger: “We know how to build cities quickly; Birmingham, Alabama was a blank spot in 1870 and a metropolitan city by 1900. I wouldn’t underestimate the American people’s ability to adapt and adjust, or our economy; history is not on the side of the doomsayer.”

    Can these new cities be reliably supplied with fresh water on a constant basis? There are reasons why homo sapiens sapiens has always congregated at specific locations and flourished. It’s not by random chance.

  33. 183
    Septic Matthew says:

    180, CFU: You didn’t approach it with skepticism, though, did you ***Septic Matthew***

    It’s only one study, but it is worth consideration.

  34. 184
    Hank Roberts says:

    And did you consider it all the way through? Know the net effect?
    I’m just asking, are you bothering to _read_ this stuff before plopping in in here as an issue for others to spend time on? Because that’s what people keep doing, posting ‘Oh Noes it will warm the planet one degree’ because they read that on some blog about some news story about the press release, all by people who didn’t read the paper.

    You can read the paper. Did you read it? What does this mean, do you think?

    “The warming caused by the wind turbines is limited to the lowermost atmospheric layers (Fig. 3). Above the planetary boundary layer, a compensating cooling effect is expected and observed in many regions, because the turbulent transfer of heat from the surface to these higher layers is reduced. This should be contrasted to the relatively uniformly distributed warming throughout the troposphere induced by rising greenhouse gases (IPCC, 2007).”

  35. 185

    Hank Roberts @ 142:

    FCH, I can’t follow the logic. If a ‘grand minimum’ lowers warming only slightly compared to increase from greenhouse gas, why would you ‘have to believe’ that the much smaller variation in solar forcing would explain so much of what’s happened?

    I’m not sure I understand what it is that you’re not following.

    The 90’s warmed significantly faster than the 00’s. I don’t think anyone can, or would — including the denialists — deny that. I also don’t think that anyone would deny — including the folks who run this blog — that we’re in the midst of the deepest solar minimum in over 100 years.

    This has happened before in the recorded history of the solar cycle, and whenever there has been a grand minimum, the result has been cooling, of some sort. That’s a bit more controversial of a statement. But what can’t be denied, except perhaps “Correlation isn’t causation”, is that SC22 was a major cycle, and SC23 wasn’t all that weak.

    My argument is that SC22 and SC23 =are= responsible for some amount of amplication of global temperature change, just as the wind down from SC23, and the anemic start of SC24 is responsible for no new HadCRUT record in over a decade. If my argument is correct, we’ll see a new HadCRUT record as SC24 gets up to whatever level is needed for that to happen.

  36. 186
    Hank Roberts says:

    > deepest solar minimum

    Well, we’re not in the midst of it now, it’s gone by.

    At the very lowest spikes, TSI was down to something like 1360, down from 1368, watts/sq. meter — but got nowhere near that low on average. Charts here up through 2009:

    If that’s the best the Sun can do, it’s not going to save us from ourselves.

  37. 187
    Completely Fed Up says:

    Septic Matthew says:
    15 March 2010 at 5:48 PM

    180, CFU: You didn’t approach it with skepticism, though, did you ***Septic Matthew***

    It’s only one study, but it is worth consideration.”

    You’re not considering it, though. You’re accepting it uncritically.


  38. 188
    HR says:

    As you say there are many 2010 papers on the possible role of solar variability on cloud cover. Here are three more.

    Journal of Atmospheric and Solar-Terrestrial Physics 72(2010)19–25

    Journal of Atmospheric and Solar-Terrestrial Physics 72(2010)151–156

    Atmos. Chem. Phys., 10, 1577–1584, 2010

    All three suggest that clouds may be affected by changes in the sun at specific regions of the earth. This may not be inconsistent with Kulmala finding no relationship in their locality. It may also be the reason no statisitically signficant link has been found on the global level.

  39. 189
    HR says:

    Sorry for the incomplete references the spam blocker was being too efficient.

  40. 190

    Hank Roberts @ 186:

    I said nothing about TSI. Read the link for my name.

    Also, wait for the blue line to be posted for the sunspot count. The big snooze will be over when Hathaway’s current prediction — which has been revised downward more than once — is below the observations, not when a month or two is above his prediction. As the climate guys like to say “that’s weather” — you can look back at SC23 and SC22 and see months that were far above the smoothed average, just as you can see them that are well below.

    The last thing I’d like to see is someone — pick you — saying “The SSN-related cooling trend is now over”, and it isn’t, and people use that to attack the validity of CO2-related warming. The question that needs to be answered, that the Sun is being so kind as to provide us the data needed to answer the question, is the relative contribution of SSN and CO2 to climate.

  41. 191
    old jim hardy says:

    Re :: an old post suggesting climate scientists and astrophysicists get together..

    Here’s a scholarly fellow proposing an unusual hypothesis about the sun’s role in all this. He’s a nuclear chemist.

    Quote: “” Thus, Earth’s climate has never, EVER been static. Our climate changes as planets move around the Sun, accelerating and deceleration of the Sun in its orbit about the centre-of-mass of the solar system. and changing the depth of the Sun’s energetic neutron core. “””

    There’s a 179 year mechanical resonance that overlays our little ice ages.

    He claims the sun’s core is isotopically quite different than previously believed and the “solar tides” thicken and thin the outer layer of hydrogen, affecting not only the intensity of solar radiation but its spectral makeup; hence it’s nonlinearity as a climate forcer.

    Quote “” SCAFETTA and WEST (2006a) and (2006c) estimate that the sun contributed as much as
    40 to 50 per cent of the 1900 to 2000 global warming and 25 to 35
    per cent of the 1980 to 2000 global warming. Their methodology
    implies that their solar output index is a proxy of all solar output,
    not only of the sun’s electromagnetic radiation. However, their
    methodology does not take account of relationships between the
    sun’s gravitational force (and its interaction with solar output) and
    climate. BUTLER and JOHNSTON (1994) concluded that their data
    strongly support the contention that solar variability has been the
    principal cause of temperature changes over the past two
    centuries. Reports prepared for the South Florida Water
    Management Authorityxiv highlight that ‘high solar activity is
    often associated with wetter periods, while lower levels of solar
    activity are associated with drier periods’. THEJLL, CHRISTIANSEN
    and GLEISNER (2003) found that only since 1973 has solar activity,
    as measured by the geomagnetic index, appeared to have a
    significant impact on the stratosphere and sea-level pressures.
    TOBIAS and WEISS (2000) have shown there is a significant
    resonant amplification between solar periodicities and climate
    periodicities. They argue that during the last few years there has
    been a shift in understanding about the dominant role of the sun on
    the earth’s climate throughout the last 11,000 years and especially
    over the last 60 years. They wrote: The IPCC dismissed any
    significant link between solar variability and climate on thegrounds that changes in irradiance were too small. Such an
    attitude can no longer be sustained. BURROUGHS (2003)
    concluded that developments about the role of the sun in climate
    change published between 1990 and 2002 could not be dismissed
    so easily as the Intergovernmental Panel on Climate Change
    (IPCC) had done.
    Variations in the strength of the sunspot cycle are accompanied
    by variations in the sun’s emission of radiation, dispersal of
    matter, the strength of the sun’s electromagnetic field and the
    strength of the heliosphere together with now increasingly welldocumented
    changes to the earth’s climate arising directly from
    these variations………. “”””

    The guy was my freshman chemistry professor in 1964 and one of the best teachers i ever had. He studied under one of Japan’s ‘Manhattan Project’ physicists (they had one too, in N Korea) so i don’t dismiss him lightly.

    Some of you may find the linked articles interesting.

    old jim himself

  42. 192
    Hank Roberts says:

    “… the Iron Sun … O. Manuel …”
    “IV. THE SUN IS A “CLOTHED NEUTRON STAR” formed by accreting iron-rich material on the pulsar (spinning neutron star) made at the supernova core [5, 6].”

    Not particularly unusual; Plimer is another fan of the notion, I recall.