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.
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All this makes me wonder if we really know as much as some seem to think we do ?
See “settled science” !
@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.
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”
|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
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.
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]
Kurt in Switzerland says:
March 19, 2012 at 3:53 am
Interesting stuff…
What is the “take home”?
;——————–
Don’t sell your coat.
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.
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.
What are the red lines in the graph?
M 7.6 earthquake hits Mexico near Acapulco.
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.php
Another strong earthquake in the wake of the recent solar storms.
http://www.vukcevic.talktalk.net/EQM7.htm
P. Solar,
How to up the anti? Show that CAGW is a load of bollocks.
vukcevic,
Free healthcare? Does that mean doctors will be slaves to all?
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.
And Bob,
Did Jesus say you should steal from some brothers in order to support others?
Barry Centre says:
March 19, 2012 at 10:59 pm
And what force is this ?
http://wattsupwiththat.com/2008/03/20/new-solar-cycle-24-goalpost-established/
Take a look at this and read all the comments. Michael R’s comment @ur momisugly 7:57 is telling. Also, the person you quote (G. S. @ur momisugly 4:51) is linked to a blog. Go there.
Note well the ‘Moderator’s Admonition’ to your own comment.
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.
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.