Sun said to be “bi-modal”
While many, including the IPCC, suggest the modern Grand Maximum of solar activity from 1950-2009 has nothing to do with the 0.4C global warming measured over that time frame, it does seem to be unique in the last three millennia.
from CO2 Science: A 3,000-Year Record of Solar Activity
What was done
According to Usoskin et al. (2014), the Sun “shows strong variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of the insufficient length of the directly observed solar activity records and of uncertainties related to long-term reconstructions.” Now, however, in an attempt to overcome such uncertainties, in a Letter to the Editor published in the journal Astronomy and Astrophysics, Usoskin et al. “present the first fully adjustment-free physical reconstruction of solar activity” covering the past 3,000 years, which record allowed them “to study different modes of solar activity at an unprecedented level of detail.”
What was learned
As illustrated in the figure below, the authors report there is “remarkable agreement” among the overlapping years of their reconstruction (solid black line) and the number of sunspots recorded from direct observations since 1610 (red line). Their reconstruction of solar activity also displays several “distinct features,” including several “well-defined Grand minima of solar activity, ca. 770 BC, 350 BC, 680 AD, 1050 AD, 1310 AD, 1470 AD, and 1680 AD,” as well as “the modern Grand maximum (which occurred during solar cycles 19-23, i.e., 1950-2009),” which they describe as “a rare or even unique event, in both magnitude and duration, in the past three millennia.”
Further statistical analysis of their reconstruction revealed the Sun operates in three distinct modes of activity – (1) a regular mode that “corresponds to moderate activity that varies in a relatively narrow band between sunspot numbers 20 and 67,” (2) a Grand minimum mode of reduced solar activity that “cannot be explained by random fluctuations of the regular mode” and which “is confirmed at a high confidence level,” and (3), a possible Grand maximum mode, but they say that “the low statistic does not allow us to firmly conclude on this, yet.”
What it means
Usoskin et al. (2014) write their results “provide important constraints for both dynamo models of Sun-like stars and investigations of possible solar influence on Earth’s climate.” They also illustrate the importance of improving the quality of such reconstructions, in light of the fact that previous reconstructions of this nature “did not reveal any clear signature of distinct modes” in solar activity.
Unfortunately, it was beyond the scope of this paper to address the potential impact of solar activity on climate. Yet the reconstruction leaves a very big question unanswered — What effect did the Grand maximum of solar activity that occurred between 1950 and 2009 have on Earth’s climate? As a “unique” and “rare” event in terms of both magnitude and duration, one would think a lot more time and effort would be spent by the IPCC and others in answering that question. Instead, IPCC scientists have conducted relatively few studies of the Sun’s influence on modern warming, assuming that the temperature influence of this rare and unique Grand maximum of solar activity, which has occurred only once in the past 3,000 years, is far inferior to the radiative power provided by the rising CO2 concentration of the Earth’s atmosphere.
Reference
Usoskin, I.G., Hulot, G., Gallet, Y., Roth, R., Licht, A., Joos, F., Kovaltsov, G.A., Thebault, E. and Khokhlov, A. 2014. Evidence for distinct modes of solar activity. Astronomy and Astrophysics 562: L10, doi: 10.1051/0004-6361/201423391.
Abstract
Aims. The Sun shows strong variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of the insufficient length of the directly observed solar activity records and of uncertainties related to long-term reconstructions. Here we present a new adjustment-free reconstruction of solar activity over three millennia and study its different modes.
Methods. We present a new adjustment-free, physical reconstruction of solar activity over the past three millennia, using the latest verified carbon cycle, 14C production, and archeomagnetic field models. This great improvement allowed us to study different modes of solar activity at an unprecedented level of details.
Results. The distribution of solar activity is clearly bi-modal, implying the existence of distinct modes of activity. The main regular activity mode corresponds to moderate activity that varies in a relatively narrow band between sunspot numbers 20 and 67. The existence of a separate Grand minimum mode with reduced solar activity, which cannot be explained by random fluctuations of the regular mode, is confirmed at a high confidence level. The possible existence of a separate Grand maximum mode is also suggested, but the statistics is too low to reach a confident conclusion.
Conclusions. The Sun is shown to operate in distinct modes – a main general mode, a Grand minimum mode corresponding to an inactive Sun, and a possible Grand maximum mode corresponding to an unusually active Sun. These results provide important constraints for both dynamo models of Sun-like stars and investigations of possible solar influence on Earth’s climate.
Pamela Gray says:
August 10, 2014 at 2:06 pm
Climate is well defined in climatology.
You give yourself way too much credit. You in fact are participating in the corrupt “fad” of regarding weather as climate. A weather regime change (change in the weather) isn’t a climatic event unless it lasts at least three decades.
Sturgis, again, the ad hominem style of response. Unnecessary.
Climate is ill-defined in current climatology in my opinion. It represents a change in its definition that I find driven by sensationalism.
Pamela Gray says:
August 10, 2014 at 2:12 pm
Your opinion is wrong. In real climatology, there has been no change.
As for the alarmist Team, to whose garbage you adhere, and their lackey media, you’re right that weather can become climate when it serves their corrupt purposes.
@ur momisugly Pamela Gray
In your post of August 10, 2014 at 10:01 am you invited me, among others to look again at your comment. I did and replied
http://wattsupwiththat.com/2014/08/06/recent-paper-finds-recent-solar-grand-maximum-was-a-rare-or-even-unique-event-in-3000-years/#comment-1706277
in what I consider to be polite manner, suggesting a course of action that might prove of otherwise your hypothesis.
Since you did not acknowledge my reply to your invitation to look at your comment, I shall assume that you have not noticed it, rather than ignored it because you found it contradictory. Either way, I am more than content to leave it at that.
The old way of talking about climate, one I still subscribe to. It’s old but it does not arbitrarily narrow the time span used to state the average temperature. And the average temperature is only one rather small factor involved in discussing climate. This is where the current fad and I disagree. To describe a change in just one (and not the major one) thing that determines climate and then refer to that one thing as “climate” change as if it was the only thing that matters is a terribly wrong use of the term climate. I will continue to describe fluctuations in average global, regional, or local temperature over the course of 100’s of years as weather pattern variation changes and regime shifts within a climate setting, not climate change. Bring on another ice sheet advancing glacial ice age and I will call that climate change.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CCcQFjAB&url=http%3A%2F%2Fwww.esrl.noaa.gov%2Fgmd%2Finfodata%2Flesson_plans%2FTeacher%2520Background%2520Information-%2520Earth's%2520Climate.pdf&ei=VuHnU8-GN-TCigK5-4D4Dg&usg=AFQjCNE1M0TAjtBAnEt4V6DG93OZbAIN0Q&bvm=bv.72676100,d.cGE
Sturgis, you are aware, I assume, that I do not subscribe to AGW attributed to the minute increase in fossil fuel use. On the contrary I consider that premise to be unsupportable, as AGW scientists do as well unless they use an amplifying mechanism (water vapor). And that has always been my leanings on this blog. I do think that the industrial fossil fuel derived anthropogenic addition to CO2 has a mathematical warming affect. I also think that TSI (and any other solar variable) has a mathematical warming and cooling affect on temperature. Neither of these two affects can be detected in the temperature series as neither have steadfastly (in the case of CO2), or cyclically (in the case of solar variation), caused global temperatures to rise or sink outside the boundary of natural variation in the past 100 years.
Could you provide links. I only ask because there was widespread famine in the early 14th century supposedly as a result of the cool, wet conditions.
John Finn
I am not at my main computer so do not have access to my research data base.
Yes, there were Very severe famines caused by rain early in the 14 th century
http://en.m.wikipedia.org/wiki/Great_Famine_of_1315–17
There was then a substantial switch to much warmer weather and a succession of famines caused by a variety of causes including drought, the plague and wars which often prevented planting or harvesting. There were also some very good harvests when man made or natural disasters allowed. They can be seen in the manorial records which I will write up in a future article
Tonyb
Olavi says:
August 10, 2014 at 1:37 pm
Leif! You are not the only person who is right in any solar related cases. There is refrees[?] whom are professionals too.
For every one that is right there are many more that are wrong.
John Finn says:
August 10, 2014 at 4:04 pm
Here’s a recent reconstruction based upon the starting date of grain harvest in Norfolk, compared to later series correlating harvest dates with temperatures in the CET:
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0CDAQFjAC&url=http%3A%2F%2Fwww.hist.unibe.ch%2Funibe%2Fphilhist%2Fhist%2Fcontent%2Fe267%2Fe325%2Fe512129%2FL-Pribyl-al-Apr-July-T-EastAnglia-12_ger.pdf&ei=jP3nU5D4C5D2oASIioKYBg&usg=AFQjCNGQcqnt_C6WtgaD4HnyRaC3Ntc1kg&sig2=UDvniMVKLbNbGqFiTjesgA&bvm=bv.72676100,d.cGU
Reconstructing medieval April-July mean temperatures in East Anglia, 1256-1431
Kathleen Pribyl • Richard C. Cornes • Christian Pfister
Received: I 7 February 20 I I I Accepted: 9 October 20 I I / Published online: 28 October 20 I I
“The reconstruction period contains decades of warmer spring-early summer temperatures (for example the 1320s to the early 1330s and the 1360s) as well as colder conditions (for example the late 1330s, 1340s and the 1380s).”
The average temperature drop over the whole period was from 13 to 12.4°C, but after the 1380s cooling the LIA set in.
mildon
I have graphed these ones as well as the titow series from the Winchester See covering some 300 years. I will include them in my forthcoming article.
tonyb
[“titow series” ?? “See” or “Sea”? .mod]
Vuk, no I did not see your response and thank you for responding. I note that the volcanic eruptions you point to between 1805-1820 do not register as being very strong in terms of stratospheric veiling based on ice core data (which is not a proxy but is actual measurement of volcanic substances in the ice cores) relative to the 1257-58 eruption. However, it is still the case that the eruptions you point to did indeed contribute to a very cold decade at the time.
climatereason says:
August 10, 2014 at 5:03 pm
Thanks very much. As you know, I appreciate all your hard work on extending the CET back in time and refining the extensions of Manley, et al.
Climate science needs more workers like you and fewer like Mann.
Pamela Gray says:
August 10, 2014 at 5:14 pm
Ice core figures are not useful data until adjusted for deposition rate, which makes them less valid, with huge error bars.
Estimation of volume of ejecta is a more precise measurement.
milo, no. Not in terms of stratospheric veiling. Volcanos can and do eject a tremendous amount of material, but what matters for ENSO consideration are the ones that eject material into the stratosphere. For that you need ice core data. And the larger ones in terms of stratospheric material show up in ice cores from both poles. These eruptions are the only ones I focus on. The rest can and do result in local and regional affects but are not global in nature.
As for triggering and sustaining, the processes will be different depending on what comes next after a big one. During the maximum boundary time span, multiple stratospheric volcanic signatures are significant in terms of polar ice core data. In addition, ENSO disruption (which according to Sturgis is climatic and not weather) does have longer term affects as does disruption in the overturning circulation (the preferred sustaining mechanism in the literature), likely in a stepwise temperature function. Indeed the temperature proxies do demonstrate this jagged slide into a colder regime shift out of the MWP.
My conjecture is that the stream of volcanic events combined with ENSO (and a nod to the preferred overturning circulation slowdown) led to an ocean body significantly out of gas to the point that we ended up in the coldest plunge later on in the period. When volcanic episodes died down the disruptions died with them, thus our slow crawl out of the LIA. CO2 and solar mechanisms need not apply.
So far, that is the current prevailing opinion in peer reviewed literature concerning the triggers and jagged slide into the deeper cold decades in that entire 2/3rds of a century period.
Before the actual location of the volcano was identified, the 1257-58 event (which shows continuous deposition over a nearly 6 year period in ice cores) was impressive to volcanologists and was the holy grail center of attention for several as they sought to identify it, and explain its climatic affects. Note: The authors use the term “climatic affects” in the literature.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=13&cad=rja&uact=8&ved=0CHgQFjAM&url=http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fjoc.891%2Fpdf&ei=NhroU_f5A6qDjAKG6oGIDA&usg=AFQjCNEOg3_dn4mRMN76bW81HT8bt8ln3w&sig2=hGnnqQA6S5SuwOw8a2euqQ&bvm=bv.72676100,d.cGE
Pamela Gray says:
August 10, 2014 at 6:36 pm
Six years is not climate.
Pamela Gray says:
August 10, 2014 at 6:18 pm
Doesn’t matter whether it’s north or south pole. All sulfate ice core “data” are subject to depositional constraints. They always vary, even when within the same overall climatic period, as the 1257 & 1280 eruptions were, for instance.
Please study up on & try to understand subjects before commenting on them. Many factors go into the deposition of sulfates in ices besides just the amount of sulphate lofted. Ambient climatic factors such as precipitation make a big difference, plus temperature, wind patterns, height of delivery, location of the eruption, etc.
http://www.reportingclimatescience.com/news-stories/article/views-on-climate-impact-of-historic-volcanoes-revised-by-study.html
“With such an accurately synchronized and robust array, Sigl and his colleagues were able to revise reconstructions of past volcanic aerosol loading that are widely used today in climate model simulations. Most notably, the research found that the two largest volcanic eruptions in recent Earth history (Samalas in 1257 and Kuwae in 1458) deposited 30 to 35 percent less sulfate in Antarctica, suggesting that these events had a weaker cooling effect on global climate than previously thought.”
Milo, be sure and let us know when the paper gets out of paywalled status. I don’t consider reading abstracts as a way to “…Please study up on & try to understand subjects before commenting on them”. Try again.
Pamela Gray says:
August 10, 2014 at 7:23 pm
Which of the CACA-spewing papers you’ve cited did you read beyond the abstract?
The paper I cited is described in detail in the long press release.
There is no evidence whatsoever showing that any volcanic eruption has changed climate, as real experts instead of the rent-seeking CACA charlatans with whom you’re in bed acknowledge. The effect of even the biggest is over in a few years at most. I very much doubt that the effect on weather of Samalas lasted six years. What data show that? Toba’s effect on world weather might possibly have lasted that long, but it was on the order of 100 times more energetic & massive, as the most powerful known eruption in tens of millions of years.
Milo, six years of reduced solar insolation due to stratospheric veiling in the equatorial band has the potential of affecting climate. Do you think your minute amount of solar variation has a greater potential? Show me.
So let’s do a thought experiment. Sulfuric veiling resulting from Mt. Pinatubo resulted in as much as a 20% reduction in solar insolation (see link). That is a huge difference at Earth’s surface, with significant deleterious affects on oceanic warming cycles that keep the ocean tanks full of gas. Volcanic reduction in solar insolation has been observed, calculated, and modeled for all the major stratospheric volcanic events recorded in the ice core data. Let’s say we are talking about the Maunder Minimum. During six years of the deepest part of the Maunder minimum, how much decrease in solar insolation would there be due to those solar changes?
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&uact=8&ved=0CF0QFjAJ&url=http%3A%2F%2Fwww.nrel.gov%2Fsolar_radiation%2Fpdfs%2Fhistory.pdf&ei=TizoU9qXGYXBiwK9_oDwBA&usg=AFQjCNH9rMyw8hxCNutl2JvcVDeZEUx1WA&sig2=wNNBUfzjer7R0IBwnsb6RA
mods
[“titow series” ?? “See” or “Sea”? .mod “)
Yes and Yes. The first being a name the second being a religious term not a misspelling of the ocean :).
tonyb
Leif Svalgaard says:
August 10, 2014 at 3:55 am
Slide 18 of http://www.leif.org/research/Does%20The%20Sun%20Vary%20Enough.pdf
…………
Thanks for the link.
Two sharp peaks between 2000 and 3000 years (before present) appear to be caused by the Earth’s magnetic field at the time, thus two maxima in the blue line may not be as high (red curve numbers could reveal more details)
I have looked at your presentation few times before. This time I did spectrum of McCracken data for Maunder minimum..
I found following 3 periods of almost equal amplitude
11.4 years at 9.3%
11.4 years is very close to a number of cycles with 11+ years periods.
16,7 years at 8.5%
16 years is one of the three most prominent component of the Earth’s magnetic field (Jackson & Bloxham based on Jault Gire & LeMouel)
27.5 years at 8.2%
28 years is GCR modulation period quoted by Hiroko Miyahara (University of Tokyo), most likely a cross-modulation product between 5 and 21.3 years, the two other most prominent components of the Earth’s magnetic spectrum.
I shall make no other comment except to say that I hope it might be of some interest to you. When I get all this organised I’ll email the McCracken’s and spectrum data files.
Milo
Thanks for your kind comment. Its highly profitable of course, what with the huge sums of money that the Koch Brothers and Big Oil keep giving me… 🙂
tonyb