Sun’s impact on climate change quantified for first time

Posted: March 27, 2017 by oldbrew in climate, modelling, Natural Variation, research, Solar physics, solar system dynamics

Quiet sun [image credit: NASA]

Solar variation influencing climate is suddenly plausible, say researchers. Who knew? Well, nearly everyone except climate modellers. Although they still mutter about human influence, the reality of the solar slowdown is starting to bite it seems. If as they suggest ‘A weaker sun could reduce temperatures by half a degree’ what might they expect from a ‘stronger sun’?

For the first time, model calculations show a plausible way that fluctuations in solar activity could have a tangible impact on the climate, reports

Studies funded by the Swiss National Science Foundation expect human-induced global warming to tail off slightly over the next few decades. A weaker sun could reduce temperatures by half a degree.

There is human-induced climate change, and there are natural climate fluctuations. One important factor in the unchanging rise and fall of the Earth’s temperature and its different cycles is the sun. As its activity varies, so does the intensity of the sunlight that reaches us.

One of the key questions facing climate researchers is whether these fluctuations have any effect at all on the Earth’s climate. IPCC reports assume that recent solar activity is insignificant for climate change, and that the same will apply to activity in the near future.

Researchers from the Physical Meteorological Observatory Davos (PMOD), the Swiss Federal Institute of Aquatic Science and Technology (EAWAG), ETH Zurich and the University of Bern are now qualifying this assumption. Their elaborate model calculations are supplying a robust estimate of the contribution that the sun is expected to make to temperature change in the next 100 years.

For the first time, a significant effect is apparent. They expect the Earth’s temperature to fall by half a degree when solar activity reaches its next minimum. According to project head Werner Schmutz, who is also Director of PMOD, this reduction in temperature is significant, even though it will do little to compensate for human-induced climate change. “We could win valuable time if solar activity declines and slows the pace of global warming a little. That might help us to deal with the consequences of climate change.”

But this will be no more than borrowed time, warns Schmutz, since the next minimum will inevitably be followed by a maximum.

Strong fluctuations could explain past climate

At the end of March, the researchers working on the project will meet in Davos for a conference to discuss the final results. The project brought together various research institutions’ capabilities in terms of climate effect modelling.

PMOD calculated what is known as “radiative forcing” taking account of particle as well as electromagnetic radiation, ETH Zurich worked out its further effects in the Earth’s atmosphere and the University of Bern investigated the interactions between the atmosphere and oceans.

The Swiss researchers assumed a greater fluctuation in the radiation striking the Earth than previous models had done. Schmutz is convinced that “this is the only way that we can understand the natural fluctuations in our climate over the last few millennia.” He says that other hypotheses, such as the effect of major volcanic eruptions, are less conclusive.

Exactly how the sun will behave over the next few years remains a matter of speculation, however, since appropriate data series have only been available for a few decades and they reveal no evidence of fluctuations during this time. “To that extent, our latest results are still a hypothesis,” says Schmutz, “and it remains difficult for solar physicists to predict the next cycle.”

But since we have been observing a consistently strong phase since 1950, it is highly likely that we will experience another low point in 50 to 100 years’ time. It could be every bit as intense as the Maunder Minimum, which brought particularly cold weather during the 17th century.

Important historical data

The research project also placed great importance on the historical perspective. The Oeschger Centre for Climate Change Research at the University of Bern compared data series on past solar activity with other specific climatic conditions.

People have been recording the number of sunspots, which correlates well with solar activity levels, for some three centuries now. However, it is much more difficult to quantify exactly how cold it was on Earth back then. “We know that the winters during the last minimum were very cold, at least in northern Europe,” says Schmutz.

The researchers still have a fair amount of work to do before they have a detailed understanding of the relationship between solar activity and the global climate both in the past and in the future.

Source: Sun’s impact on climate change quantified for first time |

  1. c777 says:

    Simple logic, LIA ~ 0.5° C cooler than ~ now , interesting.

  2. oldbrew says:

    ‘the next minimum will inevitably be followed by a maximum’ – unless we’ve just had the maximum?

  3. rishrac says:

    It’s just borrowed time is what they are saying. It’ll have a slight effect. They are extending the human induced climate change further out into the future. The sky is still falling. I don’t know where the ” closing of the window of opportunity” went. I think they are hoping that the political climate will change and the green money will follow the ever increasing levels of co2.
    So did they have to put the obligatory climate meme in there to get published ?

  4. Shoshin says:

    At least there is now a small group of researchers willing to challenge, if only tepidly, the alarmist dogma. One thing I find frustrating is the vast amount of talent that is being wasted on chasing the warmist chimera. If the researchers involved could be directed to solving actual problems the world would be far better off.

  5. erl happ says:

    About as interesting as cold porridge. Wheres the mechansm?

  6. rishrac says:

    Erl, the sun’s output varies by 0.012% ? Has no effect on climate right ?

  7. suricat says:

    erl happ says: March 28, 2017 at 12:04 am

    “About as interesting as cold porridge. Wheres the mechansm?”

    IMHO, for ‘EMR’ (Electro Magnetic Radiation) look to the ‘open windows’ for ‘warming insolation’ (mostly UVa and microwave), but forget ‘EMR windows’ for ‘cooling’, its mostly handled by ‘latent convection’ to an altitude that’s mostly an ‘open window’ to EMR.

    Thus, Earth seems to have a ‘fixed’ method/mechanism of/for ‘cooling’ (the atmospheric hydrological cycle) which is both accelerated by an increase to surface temperature (by way of vapour pressure change) and ‘buffers’ a warming insolation (with hysteresis) with ‘cloud’ that intercepts insolation at an altitude where the warming insolation can be more easily radiated to space without ever striking the surface.

    Its all about ‘depth to extinction’ (or so it would seem to me), ‘what and where’ you’re looking at, and ‘are you observing the correct energy transport medium’?

    TBH ‘The mechanism’ doesn’t exist erl. If you want “the mechansm” (mechanism I presume) it’ll be Earth’s ‘total interaction’ within Sol’s system. However, I hope I’ve offered a few hints to some of that here.

    Best regards, Ray.

  8. dai davies says:

    “for the first time” ?

    Modelling variations in solar activity – ie sunspots – has been done many times. Last year I took one of Nicola Scafetta’s sunspot models and after a few hours with a spreadsheet had a model of southern sea surface temperatures that was better than anything the IPCC climate models have produced.

    Just four cycles – 820, 193, 60 and 32 years – can give an RMS deviation of 0.03 Kº over the 135 year data period after adjusting amplitudes and phases, and tweaking frequencies a little from their solar system counterparts. The sun’s internal dynamics aren’t stable, and we can’t expect the Earth’s ocean currents to be perfectly in synch, but the link is definitely there.

    The 11 year cycle shows up clearly in the SST data but doesn’t contribute as much as the four stronger cycles. It varies over the data range which is why Fourier techniques can miss it. From memory, it was best modelled by two cycles a few years apart in period and about 130º out of phase.

    As for mechanism, that cosmic rays could seed cloud formation was not news and quite uncontroversial to physicists in the early 60s when I first heard it mentioned. Cloud chambers had been in use in particle physics for half a century. The correlation between Forbush events and liquid cloud fraction is strong evidence. CERN has provided more. The SST match does it for me.

    Cloud cover percentage is not the only relevant parameter. Granularity matters. The natural collision induced background radiation in the atmosphere can leak out between granular clouds like water through a sieve. Yesterday in Canberra we had an amazing mackerel sky – almost full coverage, but highly granular.

  9. Richard111 says:

    Anyone watching the sun? Looks like SC25 might be starting early!

  10. Stephen Richards says:

    Erl is right. The paper is conjecture without a viable mechanism.

  11. Stephen Richards says:

    Richard111 says:
    March 28, 2017 at 7:44 am

    Have you been watching AMSU Ch6 ?

  12. Jaime Jessop says:

    This is not a single study, it’s a project that has been ongoing since 2014, which has produced a number of scientific papers, some which propose the mechanism(s) whereby solar variability influences climate.

  13. AlecM says:

    Who would have thunk it: solar insolation at Earth’s surface controlling temperature?

  14. Fred Streeter says:

    @ Jaimie Jessop

    Saved me posting – but I will, anyway.

    It is pretty clear that if the Project models, then there must be ‘mechanisms’ to model.
    So, to determine what those mechanisms are, one finds the Project’s published research papers.

    And there is the Project’s site address, at the foot of the article, were one truly interested.

  15. I’ve been suggesting since about 2010 that the changing mix of particles and wavelengths from the sun alters the balance of the ozone creation / destruction process in the stratosphere so as to alter the gradient of tropopause height between equator and poles and thereby change global cloudiness.
    The main manifestation of such changes is the degree of jet stream zonality / meridionality.
    Looks like they are getting closer to that hypothesis.

  16. Sphene says:

    This may help in predicting future solar activity:

    “What emerged from the analysis were bands of magnetized activity that propagate slowly across the Sun—just like the Rossby waves found on Earth.

    “The discovery could link a range of solar phenomena that are also related to the Sun’s magnetic field, including the formation of sunspots, their lifetimes, and the origin of the Sun’s 11-year solar cycle.”

  17. Jim says:

    Oh! Now blame the nearest star. I thought that was settled, by the IPCC. Blame man.
    No way to verify the old temperatures, hmmm? Did they ever hear of the science referee to as history? Or look in museums for “temperature ” recording devices? Assures from pen and paper. Logs of explorers generally included location, and other related information. But, that may take longer then the push of a button.

  18. Paul Vaughan says:

    de Classy Phi

    “The U.S. budget debate in the coming weeks will focus on how to allocate more funds to rebuild the military and restore the relationships that the United States had with its allies and adversaries in the past, he said.”



    Bon Courage.

  19. Patrice Ayme says:

    Purely speculative, yet likely, about half a degree Celsius. And not really news, however fake… For a reality check, the average temperatures, from October 2016 to the end of February, were a full 5 degree Celsius above the average in the forty years prior, over much of the Arctic… Lose Arctic ice, and temps will shoot up further…

    It has long been clear that some sun fluctuations brought some observed fluctuations in Earth surface temperature in the last 4,000 years. However the recent quasi doubling in greenhouse gases (from 280 ppm to around 500 ppm in CO2 equivalent) is bound to wreck havoc, as it does…

    [reply] cherry-picking your data, then making assertions – not quite scientific?

  20. tom0mason says:

    Wow, the sun has an impact on our climate changing, who knew?

  21. Stephen Richards says:

    Jaime Jessop says:
    March 28, 2017 at 11:09 am

    Jaime, it is still poor science. it has no rigidity, no method that looks like real science.

  22. Climatism says:

    Reblogged this on Climatism and commented:
    Shock! Horror! The “Sun” influences climate change 😱

    The fact that the UN IPCC and CMIP5 climate models (through which governments use to formulate trillions of dollars of taxpayers money on climate policy, schemes and scams) dismiss the sun as having anything to do with climate change aka global warming, should be the biggest hint of the nefarious agenda of the UN IPCC who set the “man-made” climate narrative.

    God forbid that the sun has anything to do with climate change! How would one be able to blame evil mankind and its evil trace gasses if the sun were a key driver?

    How would Governments tax the sun? Although the Spanish government did have a such a sun-tax during its disastrous “unreliable” (wind/solar) energy experiment that literally wrecked its economy.

    That said, congratulations to (the warmist) for publishing this finding. Though I can’t help thinking that maybe the editorial board were away on spring break or maybe absent that day?! 🌞

  23. oldbrew says:

    “The discovery of magnetized Rossby waves on the Sun offers the tantalizing possibility that we can predict space weather much further in advance,” said NCAR scientist Scott McIntosh, lead author of the paper.

    Read more at:

  24. Paul,

    Would you be able to provide some narrative to go with those charts ?


  25. Paul Vaughan says:

    When people say a picture’s worth a thousand words, they’re wrong:
    It’s infinity to zero, not 1000:1.

    Prediction: A major insight on sun & phi will be wordlessly illustrated within 2 years…

  26. rishrac says:

    Paul, tallbloke or oldbrew I was looking at SORCE. The change in TSI is from 1365.5 to 1366.5 . It is not average of the year but averaged in minutes. The distance in the orbit of the earth is about 6%. I found out that the satellite that measures that is in a Lagrange position, which looks a like a golden ratio. So, I did the math between when the earth is at perihelion and aphellion . The distance is 153 million km and 158 million km. When I do the power formula for the TSI , at 1367 w/m^2 when it is closest to the sun to when it is further away, the difference is about 79 w/m^2.
    Flux =F (R1/R2)^2… 1366*( 1/ 1.03)^2 = 1287 w/m^2. The earth is 5 million km further away at this point.
    Am I missing something?

  27. blob says:

    >”When I do the power formula for the TSI , at 1367 w/m^2 when it is closest to the sun to when it is further away, the difference is about 79 w/m^2.
    Flux =F (R1/R2)^2… 1366*( 1/ 1.03)^2 = 1287 w/m^2. The earth is 5 million km further away at this point.
    Am I missing something?”

    The SORCE data contains columns for “1au” and “true_earth”. You probably want to look at the “true_earth” column (which varies between ~1315 and ~1409 W/m^2)

  28. stpaulchuck says:

    “even though it will do little to compensate for human-induced climate change. ”
    and there you have it, they will not stop flogging that dead horse no matter what.

    Scafetta and others have shown the perturbations in Earth axis, and orbit have a significant influence on our solar reception and which time of year it peaks. Add to that the various ocean oscillations (AMO, PDO, ENSO, etc) and solar oscillations and you get a very close analog of climate history. Some judicious addition of volcanoes, cosmic rays, etc., and you get really close to the climate history.

    In the meantime they’ll keep at the AGW meme as long as the money keeps rolling in.

  29. oldbrew says:

    Admitting that ‘A weaker sun could reduce temperatures’ opens the floodgates and on the other side of the same ‘coin’ must be: ‘A stronger sun could increase temperatures’.

    Quantifying that without resorting to guesswork or assertion is not going to be easy.
    – – –
    The Modern Maximum refers to the period of relatively high solar activity[1] which began with Solar Cycle 15 in 1914. It reached a maximum in Cycle 19 during the late 1950s and may have ended with Cycle 23 in 2000 as Cycle 24 is recording, at best, very muted solar activity.[2] This period is a natural example of solar variation, and one of many that are known from proxy records of past solar variability. The Modern Maximum reached a double peak once in the 1950s and again during the 1990s.

  30. Paul Vaughan says:

    OB suggested: “Quantifying that without resorting to guesswork or assertion is not going to be easy.”

    Just drop the uniformity assumption.

  31. rishrac says:

    Thanks blob, the swing in watts/m ^2 is greater than what I calculated. When they produce papers with increased wattage of less than 2, it makes me wonder. While the orbit maybe in planetary terms a near perfect circle, slight variations are probably making differences in climate. The sun is also moving in an orbit, those small but important angles add up. The orbit could change between 1 or 2 million km. A little further away, or a little closer. Also, the position of the earth when it is closet and furthest away changes by a day each year. There are just a lot of factors.

    On the one hand, I’d like to see a deep solar minimum, which for various reasons I don’t think is going to happen. But then if it really is a variation in some force that causes the earth to cool, life will not be very good. Then it may be nothing but coincidence. The earth could have been on a fairly consistent warming trend, except for external events that caused cooling. There is some evidence that during the most recent cooling periods, we may have had a close encounter with a comet.

    Patrice, the dubious nature of CAGW is in question when it comes to co2. The reasons are too many too list here. However, it is not incumbent upon a skeptic to define what caused a previous time period that was warmer without increased co2 levels. There have also been periods when it was colder. Neither of those periods have been addressed in context. Overall, the last 20 years has been anything but catastrophic, in spite of pronouncements of this storm being stronger or hottest year ever. The models and predictions don’t match reality. Its more than a coincidence that some of the research done on here matches exactly the work of a Chinese mathematician 1,000 years ago ( actually, now is more exact) and goes beyond it in scope. .

    I’m still going for changes in the sun that affect climate. Why? Because that is the evidence that we have. The affects may not necessarily be a direct result of lower TSI. At least to me, the recent year long quite of the sun that resulted in lower global temperatures, reinforced that idea. That was a year, I wonder what would happen if the sun went quite for 40 or 50 years .

  32. Patrice Ayme says:

    Rishrac: Thanks for the answer. I do agree that the Sun’s activity causes changes of Earth temperature changes. And I have long written about this:

  33. Patrice Ayme says:

    There is no other plausible explanation for the Little Ice Age, or the Middle Age Warming Period, except for variation in the Sun’s output. The Little Ice Age corresponded to the Maunder Minimum in sun spots, indicative of lower convection, thus activity, in the upper layers of the sun.

    It is indeed very valuable to make back-modelling of preceding warming episodes (which seem to occur every 1,000 years or so). It is indeed likely those fluctuations, in the last 7,000 years, were caused by the Sun.

    However considering the orbital warming (“Milankovitch” cycles; actually a theory more than a century older than that), some other models predict a cooling, which would have been prevented by increased methane from cattle herding (humans made it so that there would be more cattle, less rabbits). CH4 is much more efficient a greenhouse gas than CO2.

    The hottest year, globally, including the ocean surface atmospheric temperature was 2016, and, before that, 2015. It is true that the Sun was quieter in recent decades. However a solar scientist I know smirks that will probably not last…

    As my 2009 paper referred above shows, the increasing warming of recent decades occurred in spite of the increasing quietness of the Sun.

    CAGW, Catastrophic Anthropogenic Greenhouse Warming, is around the corner. It may well start with a tsunami somewhere, induced by a methane hydrates slide somewhere (as happened with the Storegga slides, off Norway, 8,200 years ago)… Otherwise the high density of CO2 will be enough to register year after year of higher temperatures. Notice that El Nino seems already on its way back, after just a year without, another indication of CAGW… Also notice both Arctic and Antarctic ice covers reached minimum maximum and minimum minimum, respectively, a few weeks ago. At some point, the warming will quit its linear regime, and become wildly nonlinear.

  34. Patrice,

    Your problem is that no climate changes have been observed beyond those to be expected from solar variations. Although the sun has been quieter during cycle 24 it is correct that cooling proper has not yet begun but according to satellite data the previous warming trend has come to a halt.
    The warmth of 2016 and 2015 is statistically insignificant compared to that of 1998.

  35. rishrac says:

    First off, your graph of using a very narrow gauge of solar activity. On this blog, I asked and was answered about the true earth TSI. The difference in the earth’s orbit changes the w/m^2 by 94 in one year. ( SORCE) The TSI you are using is at a Lagrange point. I had calculated 79. The actual is greater. The implication is that this is not a neat little average that you can use to to describe black body radiation. (Kepler’s law comes into play) Nor can it be used to calculate for energy balance and flow in simple terms. None of the numbers in all of the papers I’ve seen are right. How do you quantify a retained heat from solar at 240 w/m^2 when the wattage varies by 94 w/m^2 ? The entire outgoing was measured at 103 w/m^2, years ago.

    It is unfortunate that I don’t think this solar cycle will be as deep or as long to prove one way or the other. (not discounting a colder world is much less desirable than a warmer one)

    Second, I have tons of research prior to the manufactured hockey stick . The connection between solar activity and climate seems fairly certain. What those connections are remains to be seen. Does a quite sun set off more volcanic activity for example would be an indirect result.

    The problem, as I see it, is that the AGW has failed beyond any reasonable scientific standards. The list of failures is extensive. Cold fusion by comparison has more validity than AGW. Next, almost right from the start they knew that the very ice core data that they were using to prove the relationship between co2 and temperature was that temperature led co2 by 800 years. You remember the Al Gore statement and chart ” let’s go back in time. What pops out at you? ” Additionally, the graph showing total co2 in relation to yearly temperature anomaly is misleading. Graphing the ppm per year against the temperature clearly shows that co2 follows temperate for the last 60 years (numbers from NOAA). AGW is backwards. The CAGW community knew this and yet they still continued on. It is just about the only thing I am certain of.

  36. rishrac says:

    Patrice, the only model that actually works to describe warming and cooling backwards is solar activity. Additionally, there has been a lot of work done on this blog that provides finer details into planet positions and beats.

    CAGW models, all of them, cannot not project backwards or forwards.

  37. oldbrew says:

    rishrac says: ‘Am I missing something?’

    Probably – the ocean’s thermal inertia

    (Ignoring Wiki’s assertions about human influences)

  38. rishrac says:

    Oldbrew, there’s more than a half a degree difference in just the orbit of the earth around the sun. And of course, as you may know, I have deep concerns about the IPCC

  39. oldbrew says:

    On the Kelvin scale a difference of 0.5 degrees is quite small i.e. a change of less than 0.002%.
    [Example: 288.5K / 288K = 1.001736]

  40. oldbrew says:

    patrice says: ‘As my 2009 paper referred above shows, the increasing warming of recent decades occurred in spite of the increasing quietness of the Sun.’

    Again – thermal inertia. Plus a recent large El Nino, which may turn out to be the ocean expelling surplus heat to balance with a less active sun.

  41. Patrice Ayme says:

    We have paleontological records of climate extending millions of years. The fact El Nino is coming back, after a strong El Nino last year is revealing: its normal cycle is seven years, except on a warming planet, when it can run every year.
    El Nino is the engine of warming of the planet, as it churns cold Pacific water with warm eastern Pacific waters.
    Global temperatures were warmer in 2016 than in 2015, which was warmer than 2014, itself warmer than 2010, 2013, etc. El Nino 1998 is in eight position…

  42. oldbrew says:

    The NOAA is under investigation for fiddling climate data.

    Good enough for Wikipedia and Patrice though 😦

  43. rishrac says:

    Patrice, as noted earlier the temperature is not much different than in 1998. The issue isn’t whether there has been warming. The issue is linking co2 to temperatures. There is no doubt that co2 follows temperature. In fact, it is difficult to ascertain how much anthropogenic co2 is a component of the co2 levels. If anthropogenic co2 is the sole source of additional co2, then the total amount that has been produced over the 1998 level has disappeared which is substantial.
    NOAA changed the co2 ppm per year AFTER they were made aware that the ppm followed temperature. It also follows the solar and cosmic ray activity.
    The tampering with data is an ongoing issue. They have cooled the past and warmed the present. They can continue to do this by just moving the wave. Since March of 2015 NOAA has changed the temperature record at least twice.

  44. oldbrew says:

    German Springs Arriving Later As Wikipedia Caught Whitewashing, Disinforming!
    By P Gosselin on 1. April 2017

    “It is a pity that the original excellent concept of a voluntarily written online encyclopedia has been hijacked by political activists and rendered useless in a number of sensitive subject areas”

    – See more at: