Geomagnetic data reveal unusual nature of recent solar minimum

Sun

Sun (Photo credit: gr33n3gg)

From the American Geophysical Union weekly highlights:

Key Points

  • Minimum 23-24 showed recurrence intervals of 9.0 and 6.7-d
  • Historical geomagnetic activity data show that minimum 23-24 was unusual
  • The heliosphere during minimum 23-24 had unusual sectorial structure

Since the mid-1800s, scientists have been systematically measuring changes in the Earth’s magnetic field and the occurrence of geomagnetic activity. Such long- term investigation has uncovered a number of cyclical changes, including a signal associated with 27-day solar rotation. This is most clearly seen during the declining phase and minimum of each 11-year solar cycle, when the Sun’s magnetic dipole is sometimes tilted with respect to the Sun’s rotational axis. With the Sun’s rotation and the emission of solar wind along field lines from either end of the solar magnetic dipole, an outward propagating spiral-like pattern is formed in the solar wind and the interplanetary magnetic field that can drive 27-day, and occasionally 13.5-day, recurrent geomagnetic activity. Recurrent geomagnetic activity can also be driven by isolated and semipersistent coronal holes, from which concentrated streams of solar wind can be emitted.

During the most recent solar minimum, which took place from 2006 to 2010, however, several researcher groups noticed 6.7-day and 9-day recurrent changes in geomagnetic activity, and similar patterns in the interplanetary magnetic field, and the solar wind.

Using modern data covering the previous two solar minima, these higher-frequency occurrences were judged to be unusual. Love et al. analyzed historical geomagnetic activity records from 1868 to 2011 and find that the 6.7-day and 9-day recurrent changes were actually unique in the past 140 years. They suggest that the higher-frequency changes in geomagnetic activity are due to an unusual transient asymmetry in the solar dynamo, the turbulent, rotating plasma deep within the sun which generates the magnetic field.

Source: Geophysical Research Letters, doi:10.1029/2011GL050702, 2012
http://dx.doi.org/10.1029/2011GL050702

Title: Geomagnetic detection of the sectorial solar magnetic field and the historical peculiarity of minimum 23-24

Authors: Jeffrey J. Love and E. Joshua Rigler: Geomagnetism Program, U.S. Geological Survey, Denver, Colorado, USA;

Sarah E. Gibson: High Altitude Observatory, NCAR, Boulder, Colorado, USA.

###

Abstract:

Analysis is made of the geomagnetic-activity aa index covering solar cycle 11 to the beginning of 24, 1868–2011. Autocorrelation shows 27.0-d recurrent geomagnetic activity that is well-known to be prominent during solar-cycle minima; some minima also exhibit a smaller amount of 13.5-d recurrence. Previous work has shown that the recent solar minimum 23–24 exhibited 9.0 and 6.7-d recurrence in geomagnetic and heliospheric data, but those recurrence intervals were not prominently present during the preceding minima 21–22 and 22–23. Using annual-averages and solar-cycle averages of autocorrelations of the historical aa data, we put these observations into a long-term perspective: none of the 12 minima preceding 23–24 exhibited prominent 9.0 and 6.7-d geomagnetic activity recurrence. We show that the detection of these recurrence intervals can be traced to an unusual combination of sectorial spherical-harmonic structure in the solar magnetic field and anomalously low sunspot number. We speculate that 9.0 and 6.7-d recurrence is related to transient large-scale, low-latitude organization of the solar dynamo, such as seen in some numerical simulations.

 

About these ads

68 thoughts on “Geomagnetic data reveal unusual nature of recent solar minimum

  1. This can be easily linked to SUVs.

    In fact the Sun’s remarkable stability over billions and billions of years has been broken by the increased IR emitted by the third planet in the Solar System, throwing off-balance the exquisitely delicate workings of millions of H bombs exploding every second.

    If nations don’t pull themselves together and stop GHG emissions by tomorrow, capitalism is going to destroy the Galaxy and [that's enough catastrophism for this century -Eds]

  2. I wonder if it would be safe to wonder out loud if a difference in the center of rotation of the system might cause some ‘slop’ and “transient asymmetry”… or if that strays too close to That Which May Not Be Said about all things solar and rotational…

  3. Get real you wise guys, if you don’t buck up & stop GHG emissions, Klaatu & his mates from out there will come down & most likely (95% confidence level) give us all a jolly good ticking off, they may even wag the fingers at us, which would frankly be an insult too far, don’t you know! ;-)

    Don’t you just love all these things we’re suddenly discovering about the Sun? Amazing, who’d a thunk it!

  4. We almost got the magic word “unprecedented” in there. Shame, it won’t qualify for AR5 without that (well it’s too late anyway, I know).

    Seriously what is unprecedented is the low level of activity of this minimum. I’m not sure that this finding is anything more exciting that saying when there’s less noise you can spot small amplitude signals that otherwise get drowned out.

    As the 29d cycles are only seen during minima , the yet smaller amplitude 13.5d cycles are only detectable during very low minima.

    Interesting stuff though.

  5. The abstract is a tease, but I have questions that might be answered in the full article.

    “Previous work has shown that the recent solar minimum 23–24 exhibited 9.0 and 6.7-d recurrence in geomagnetic and heliospheric data, but those recurrence intervals were not prominently present during the preceding minima 21–22 and 22–23. ”

    Am I drawing the correct inference that improved instrumentation has been examined and ruled out?

    “Using annual-averages and solar-cycle averages of autocorrelations of the historical aa data, we put these observations into a long-term perspective: none of the 12 minima preceding 23–24 exhibited prominent 9.0 and 6.7-d geomagnetic activity recurrence.”

    I can’t see how any sort of improved data reduction technique can draw out information that wasn’t present to begin with. If these signals were lost in the noise, yes. But if they were too short to be recorded, or the variations were beyond the sensitivity of the instrumentation, I can’t see how they’d get the information, regardless of technique.

    Could someone with access to the article comment, please.

  6. Maurizio Morabito (omnologos) says:
    March 19, 2012 at 3:14 am
    >>
    This can be easily linked to SUVs. In fact the Sun’s remarkable stability over billions and billions of years has been broken by the increased IR emitted by the third planet in the Solar System, throwing off-balance the exquisitely delicate workings of millions of H bombs exploding every second.
    >>

    You’ve hit the nail in the head. You know just this morning I was wondering how we could “ratchet” up the press for action and how we could up the anti from “save the world” to “SAVE THE UNIVERSE” ! And here’s the answer The Lord works in wondrous ways ….

    This wonderful research shows how we are destabilising the SUN ! Even if it means giving up our entire way of life , our wealth , democracy and our freedom to a new world government (sorry “governance”) , we just don’t have any choice now, do we?

    We must SAVE THE UNIVERSE !

  7. Science is starting to pick up anomalies attached to SC24. The last time the Sun behaved like now was before we could measure anything, so everything is new. The “force that dare not speak its name” will eventually come to prominence, but unfortunately this may take some time.

  8. I’ve wondered if coupling between the magnetic field and all those molecules whizzing around in jet streams could be one of Willis’s thermostats. Could that be another (long wave) mechanism for the earth to shed energy, outside of IR?

    I don’t have the chops to answer the question.

  9. Geoff Sharp says:
    March 19, 2012 at 4:51 am
    /////////////////////////////////////

    Quite so.

    When you are dealing with a system that is about 4.5 billion years old (OK Earth’s climate is somewhat less old), it is impossible to say what is new and what is unprecedentd.

    Our snapshot is far to short to draw amy such far reaching conclusions.

  10. Michael Larkin says:

    Kurt in Switzerland says:
    Interesting stuff…
    What is the “take home”?

    +1
    ———————————————
    My takeaway is: Another data point that demonstrates the concept of a “solar constant” is fundamentaly flawed and any model or theroy of terrestrial climate that assumes so is also fundamentaly flawed.

  11. I suspect this is just the build up to an explanation for why the world is not warming. The Sun’s unprecedented shivers trump global warming’s unprecedented fever. But when the shivers are over the fever will still be there so we still need to give them lots of our money.

  12. Basically, the sun usually resonates with a 27 day period and a first harmonic of 13.5 days. Internal changes in the sun have stimulated the 2nd and 3rd harmonics with periods of 9 and 6.7 days respectively.
    To visualize the vibrations, imagine a sphere sliced like orange wedges. The fundamental (27 day) has one slice, pole-to-pole in half, the first harmonic is sliced in quarters, the second harmonic is sliced pole-to-pole in sixths, and the third harmonic is sliced pole-to-pole in eighths.
    The sectors vibrate alternately in and out, with adjacent sectors vibrating out of phase with each other.

    http://panaworks.com/lana/fun/spheres.htm

  13. we would have more fun (& interest) if they reported on the recent Forbush-cloud relationship.
    Isn’t anyone bothered to find out results, or do we have to wait two years for a paper for someone ‘fit in the data to a model’?

  14. If I’m reading the graphs correctly, was there also a relatively low average during the period when the US experienced the dust bowl, depression, etc.?

  15. The appearance of a 9 day cycle is somewhat worrying. Why ? While the 13.5 and 6.7 day cycles clearly have 2 and 4 cycles within the principle cycle respectively, the 9 day cycle has 3.
    Those who are familiar with chaos theory will know that the name ‘chaos’ comes from a classic 1975 paper (http://www.its.caltech.edu/~matilde/LiYorke.pdf) entitled ‘Period three implies chaos’. The authors proved that any system that shows a regular cycle of period three will also show cycles of every other period, as well as completely chaotic behavior.

  16. richard verney says:
    March 19, 2012 at 5:08 am

    I was thinking along the same lines. Man has been measuring the sun for less than 200 years out of the [billions] that it has existed. We know there are limitations to the variance (cycles) or we wouldn’t be here, but what are those limitations? Some great observations. I don’t know if there is a ‘take home’ other than … “looks what it’s doing now!”

  17. Sarc/on
    Without the ethics guru Glick at the helm leading the way on Ethics in Science; his departure provides a window to jam through all kinds of stuff which may not have his stamp of approval :-}

  18. @cal – but did the sun have a fever in the 19th and 20th century and are the so called shivers in actual fact normality?

  19. In my earlier post regarding chaos theory I should have gone on to mention ‘period doubling’. Briefly, whenever a system makes a transition from stable oscillation to chaotic behavior, (and any system at all that shows period three can do this), the process commences with period doubling (http://en.wikipedia.org/wiki/Period-doubling_bifurcation). Cycles of 2, 4, 8 appear with increasing rapidity, and then chaos ensues.
    The appearance of a cycle of period 4 suggests this could be happening. Let’s hope not. I have no idea what happens if this solar cycle becomes chaotic, but it might be better not to know !

  20. It seems to me that this is saying we should have seen a pretty extensive cooling of the planet in the past few years. Since temperatures have been flat, there are really only two take aways. Either, (1) solar variations aren’t as important as I would have thought, or (2) something besides the sun is causing the Earth to absorb a higer percentage of the sun’s energy.

    Or, I suppose, it could be a little of both.

  21. ref. “take home” / takeaway, …

    Are there studies and/or evidence suggesting a relationship between geomagnetic parameters (esp. resulting from solar activity) and geoclimate?

    Certainly the evidence is strong for correlation between a dearth of sunspots and a cooler geoclimate. And a longer, flatter solar cycle would appear to correspond to the same.

    My question is thus: is this merely an observation of “here’s something different”, so “stay posted”, or are there any rough order of magnitude conclusions to be drawn?

    Kurt in Switzerland

  22. Henry says:

    http://wattsupwiththat.com/2012/03/19/geomagnetic-data-reveal-unusual-nature-of-recent-solar-minimum/#comment-928364

    Theoretically, it is true that some back radiation from the CO2 would be sent back straight to the sun. But I was only joking as to it having any effect, of course.

    Henry@ Rick Powell
    It seems the increasing greenery on earth is trapping some heat, but that is only a minor factor. I suspect ozone could be one of the (main) culprits of the warming. In its turn, the ozone hole and the thickness of the ozone layer depend on the sun
    UV + O2 + O => O3

    http://www.letterdash.com/HenryP/henrys-pool-table-on-global-warming

  23. Radio experiments started in the 1860s. Hertz beam RF in to space in 1886, coincident? The sun can only be saved if we stop all RF transmitions immediately.

  24. I have two requests:

    1) Are there data-sets or graphs that show the “accurate” diameter of the Sun over, say, 100 [or better, 200] years? Surely that is not a constant?!?! This is difficult to determine on a gaseous body, but I’m sure some group has measured it. I can’t find any record.

    2) Are there data-sets or graphs that show the heights of the regions of Earth’s atmosphere? Specifically, at the equator, mid-latitude, poles, etc., for each month for 100 or better 200 years? Again, this would be difficult to determine, but consistent measurement techniques would give good estimates.

    More data to determine how the Sun effects our atmosphere. Relationship of magnetic field strength to Sun’s diameter.

    Thanks

  25. Honestly now so what’s the big deal. There isn’t a thing anyone can do about it so why get excited. The sun is so big that the best anyone can do is to “roll with the punch i.e. adapt.

  26. Ahem! As the new head of the InterGalactic Panel of Concerned Cronies to save the universe I’ll be needing some suitable transport to get the message out there

    http://www.bigredkev.com/2010/05/knight-xv-worlds-largest-suv.html

    and as such will be taking applications from suitably like minded concerned cronies forthwith (eminently recyclable envelopes and brown paper bags are available for a small fee from my personal secretary)
    Remember it’s only for Galactic Gaia we will fight the good fight with your Galactic vacuum taxes folks!

  27. Err..in my haste to get saving Galactically I almost forgot to mention- Strictly no email applications.

  28. vukcevic says:
    March 19, 2012 at 6:01 am

    we would have more fun (& interest) if they reported on the recent Forbush-cloud relationship.
    Isn’t anyone bothered to find out results, or do we have to wait two years for a paper for someone ‘fit in the data to a model’?

    I’m not sure what you’re asking for here. Since the Forbush-cloud relationship isn’t particularly recent, I assume there is something about the recent data that is interesting. ??? Sorry for being thick but I am curious about what you meant.

  29. Zdrastvuy Comrade Bob
    Last week there was the deepest Forbush decline in years (~15%) , here is the tail end of it:

    Proletariat still asleep ?

  30. Rick Powell says:
    March 19, 2012 at 7:02 am
    It seems to me that this is saying we should have seen a pretty extensive cooling of the planet in the past few years. Since temperatures have been flat, there are really only two take aways. Either, (1) solar variations aren’t as important as I would have thought, or (2) something besides the sun is causing the Earth to absorb a higer percentage of the sun’s energy.

    Or, I suppose, it could be a little of both.

    “we should have seen a pretty extensive cooling of the planet in the past few years”

    Or as many researchers have been pointing out that there is a considerable lag as the oceans take a long time to cool. The normal analogy is when you boil a pan of water turning off the heat doesn’t cause a rapid drop in temperature – it just stops rising and starts to slowly cool. As you point out that appears to be what is happening atmospheric temperatures have been flat. But look at the ENSO SST page here and the preponderance of dark blue in the oceans of the Unisys Anomaly plot.

    Let’s just hope that the sun has turned down only to simmer and not too low.

  31. Too many have taken this post to post jokes, which is understandable, however it is a very serious matter if these changes are having a direct effect on GMF.

  32. @vukcevic says:
    March 19, 2012 at 9:16 am
    Proletariat still asleep ?
    Dear Vuk: Human beings have a self defense psychological “buffer” which impedes them to see reality when it entails something scaring. Self deceiving when in excess impedes even well respected members of the academia to reject the obvious.

  33. @Rick Powell says:
    >>It seems to me that this is saying we should have seen a pretty extensive cooling of the planet in the past few years. Since temperatures have been flat, there are really only two take aways. Either, (1) solar variations aren’t as important as I would have thought, or (2) something besides the sun is causing the Earth to absorb a higer percentage of the sun’s energy.<<

    These changes don't correlate directly. Regardless of whether the temperatures are increasing or decreasing, it's like money in the bank gathering interest. The effects of reduced or increased solar electromagnetic activity will be cumulative over time, I believe. That's why you see a lag time of 800 years between increased temperatures and accumulation of CO2 in the atmosphere, and why the CO2 continues to increase even as temperatures begin to cool. The oceans are doubtless a major factor.

  34. Should see a strong spike in the SWPC chart for geomagnetic activity for March. After all the misses and glancing blows, got hit pretty good this month with flares and high solar winds.

  35. Here is one which shows all of this month’s decline

    That is an X5 flare causing that decline, I believe. We’ve had some rather spectacular flares from one spot group.

  36. vukcevic says:
    March 19, 2012 at 5:22 am

    Just added spectral response for the Ap max as measured at Tromso.

    http://www.vukcevic.talktalk.net/Tromso.htm

    _____________________________________
    Thanks for the graph and thanks for adding a legend so we can figure out what is what. Your graphs add a lot to the discussion.

  37. Rick Powell says:
    March 19, 2012 at 7:02 am

    It seems to me that this is saying we should have seen a pretty extensive cooling of the planet in the past few years. Since temperatures have been flat, there are really only two take aways. Either, (1) solar variations aren’t as important as I would have thought, or (2) something besides the sun is causing the Earth to absorb a higer percentage of the sun’s energy.

    Or, I suppose, it could be a little of both.
    ____________________________________
    Do not forget the oceans store heat and act sort of like a capacitor, so changes to the sun are not going to be seen reflected in the temperature immediately. I would hazard a guess that the changes will be in ENSO.

    Also we HAVE seen changes. The Jet Streams have become more “loopy” http://chiefio.wordpress.com/2011/03/06/of-turbulence-hadley-ferrel-cells-and-loopy-jet-streams/

    The whole idea that there is ONE variable that is responsible for the climate/temperature should be a non-starter.

  38. Hmm

    As it happens I have been mucking with extracting the cycles in the sunspot numbers going back to 1750. It has been quite a fascinating exercise, using the Periodicity Transform, mentioned by Willis Eschenbach previously.

    The correlation with the the orbits of Jupiter, Saturn and Neptune are striking (or was that Uranus – I always forget which is closer).

    What effect does the gravitational effect of these planets have on the sun’s “dynamo”?
    Presumably the effect will be observable in other other ways too?

    (As an aside – I tried forecasting the monthly SSN from the cycles I extracted. The result is a low cycle this time around followed by negative number after 2020???? That’s not possible. A bit of thought shows that I should really take account of a sign change from one cycle to the next. The change is lost in the method of recording sunspot numbers. Resolving that problem is tommorrow’s work !-)

  39. All this makes me wonder if we really know as much as some seem to think we do ?

    See “settled science” !

  40. @Gail Combs: However that ONE variable is electromagnetism (as the part of magnetism never separates from electricity- the “right hand rule” or the “Oersted Law”-)…We cannot say anymore as it is forbidden by the “post normal” inquisition.

  41. Rosco says:
    March 19, 2012 at 3:49 pm

    All this makes me wonder if we really know as much as some seem to think we do ?

    See “settled science” !
    ______________________
    more like “Infant Science”

  42. |This can be easily linked to SUVs.
    Gee thanks Maurizio Morabito (omnologos).
    I actually found this article interesting and was interested in reading peoples comments right up until I read your sarcastic pessimistic comment. Seriously, this has nothing to do with the “Climate change debate” and your bulls#!t comment doesn’t belong on this page

  43. adolfogiurfa says:
    March 19, 2012 at 10:23 am

    @vukcevic says:
    March 19, 2012 at 9:16 am
    Proletariat still asleep ?
    Dear Vuk: Human beings have a self defense psychological “buffer” which impedes them to see reality when it entails something scaring. Self deceiving when in excess impedes even well respected members of the academia to reject the obvious.

    Please don’t let my nic get up your nose too badly. I call myself commieBob for two reasons:

    Jesus makes it clear that I am my brother’s keeper.
    I think government funded medical care is a good thing.

    In most other respects, I’m libertarian.

    Anyway, the proletariat has figured out that CAGW is wrong, so they aren’t that unconscious.

  44. Geoff Sharp says:
    March 19, 2012 at 4:51 am

    The “force that dare not speak its name” will eventually come to prominence, but unfortunately this may take some time.

    And what force is this ?
    Can you provide some clues ?

    [Moderator's Admonition: Don't get too cute. There are topics Anthony prefers not to discuss. Capice? -REP]

  45. Kurt in Switzerland says:
    March 19, 2012 at 3:53 am

    Interesting stuff…
    What is the “take home”?

    ;——————–

    Don’t sell your coat.

  46. Gail Combs says:
    March 19, 2012 at 3:00 pm
    Also we HAVE seen changes. The Jet Streams have become more “loopy”

    Jet Steams have something in common with IPCC.

  47. commieBob says:
    March 19, 2012 at 7:12 pm
    …… I think government funded medical care is a good thing.

    Hi Bob
    Free education for all who want it
    Free health care for all who need it.
    (I was fortunate and benefited from both)
    Protect the weak and infirm, for the rest work and responsibility; no free loading for a local yobo or the crooked city slicker.
    Free speech and access to information with the consequences for abuse.

  48. I think government funded medical care is a good thing.

    Ah. A political system based on theft. What will they think of next? Better – what can citizens be encouraged to support? I know. I know. “What is mine is mine and what is yours is the people’s.”

    Clever those communists.

  49. M Simon says: March 20, 2012 at 9:30 pm
    vukcevic,
    Free healthcare? Does that mean doctors will be slaves to all?

    Or only to those who can afford them?
    Free health care for all who need it. A good doctor is capable to decide who needs it, and who doesn’t.
    That is what we pay our national insurance contribution for; it amounts to about 8% for an average income earner, for high earners progressively falls off, so even $1,000,000 earner/month doesn’t pay more than about $1000/mnth ; United Kingdom is hardly a communist country.

  50. I note that this study does not include the period from 1848 through 1859, which has some similarity to the solar activity of last 11 years. The notorious Carrington Event, solar mega-flare, ocurred in late 1859. Hopefully, the next one will shoot off in another direction.

Comments are closed.