We’ve been watching the progress on the WUWT solar reference page in this plot from Dr. Leif Svalgaard:
Solar Polar Fields – Mt. Wilson and Wilcox Combined -1966 to Present
Leif Svalgaard – Click the pic to view at sourceNow, NASA has decided to call the flip. Video follows.
Something big is about to happen on the sun. According to measurements from NASA-supported observatories, the sun’s vast magnetic field is about to flip.
“It looks like we’re no more than 3 to 4 months away from a complete field reversal,” says solar physicist Todd Hoeksema of Stanford University. “This change will have ripple effects throughout the solar system.”
The sun’s magnetic field changes polarity approximately every 11 years. It happens at the peak of each solar cycle as the sun’s inner magnetic dynamo re-organizes itself. The coming reversal will mark the midpoint of Solar Cycle 24. Half of ‘Solar Max’ will be behind us, with half yet to come.
Hoeksema is the director of Stanford’s Wilcox Solar Observatory, one of the few observatories in the world that monitor the sun’s polar magnetic fields. The poles are a herald of change. Just as Earth scientists watch our planet’s polar regions for signs of climate change, solar physicists do the same thing for the sun. Magnetograms at Wilcox have been tracking the sun’s polar magnetism since 1976, and they have recorded three grand reversals—with a fourth in the offing.
Astronomers at the Wilcox Solar Observatory (WSO) monitor the sun’s global magnetic field on a daily basis. WSO home page
Solar physicist Phil Scherrer, also at Stanford, describes what happens: “The sun’s polar magnetic fields weaken, go to zero, and then emerge again with the opposite polarity. This is a regular part of the solar cycle.”
A reversal of the sun’s magnetic field is, literally, a big event. The domain of the sun’s magnetic influence (also known as the “heliosphere”) extends billions of kilometers beyond Pluto. Changes to the field’s polarity ripple all the way out to the Voyager probes, on the doorstep of interstellar space.
When solar physicists talk about solar field reversals, their conversation often centers on the “current sheet.” The current sheet is a sprawling surface jutting outward from the sun’s equator where the sun’s slowly-rotating magnetic field induces an electrical current. The current itself is small, only one ten-billionth of an amp per square meter (0.0000000001 amps/m2), but there’s a lot of it: the amperage flows through a region 10,000 km thick and billions of kilometers wide. Electrically speaking, the entire heliosphere is organized around this enormous sheet.
During field reversals, the current sheet becomes very wavy. Scherrer likens the undulations to the seams on a baseball. As Earth orbits the sun, we dip in and out of the current sheet. Transitions from one side to another can stir up stormy space weather around our planet.
An artist’s concept of the heliospheric current sheet, which becomes more wavy when the sun’s magnetic field flips. More
Cosmic rays are also affected. These are high-energy particles accelerated to nearly light speed by supernova explosions and other violent events in the galaxy. Cosmic rays are a danger to astronauts and space probes, and some researchers say they might affect the cloudiness and climate of Earth. The current sheet acts as a barrier to cosmic rays, deflecting them as they attempt to penetrate the inner solar system. A wavy, crinkly sheet acts as a better shield against these energetic particles from deep space.
As the field reversal approaches, data from Wilcox show that the sun’s two hemispheres are out of synch.
“The sun’s north pole has already changed sign, while the south pole is racing to catch up,” says Scherrer. “Soon, however, both poles will be reversed, and the second half of Solar Max will be underway.”
When that happens, Hoeksema and Scherrer will share the news with their colleagues and the public.
Source: NASA press release, h/t to Dr. Leif Svalgaard
VIDEO:
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And I expect the new slow bow shock model will be falsified if and when voyager measures a new region of conditions further out the solar system.
So, your ‘expectation’ is now valid science?
Well true science is DIY, but since I can’t make my own space probe I’ll just have to rely on voyager 1 results. Same for most people. Apart from that, yes it’s science. But since any unbiased scientist should know this I wonder if you alluding to asserting that predicting a bow shock is science, but predicting no bow shock isn’t science.
Note that McComas is a co-author of the slow bow shock paper I cited…… the person you quote
If a spot of irony is half of your rebuttal to my comment then its a pretty weak rebuttal.
It is time for you to take your ball and go home rather than try to play with the big boys.
It’s already evident to us, but if I were you I wouldn’t parade your believe that science can only be done by ‘big boys’ – i.e. those who occupy the highest ivory towers in academia. Science is done by everyone. When you’ve got a select few telling everyone else how things are, then that’s religion.
Here’s a question : Since the solar wind was measured to effectively cease in the region of voyager 1 in 2010, how is there going to be any bow shock at all?
Because the bow shock is not due to the solar wind ceasing, but to the solar system moving against the interstellar medium at 29 km/s.
The only sense I can make of that is that the 29km/s interstellar wind is predicted to be hitting the ceased solar wind. I can’t see any sensible reason why you’ve used the term ‘solar system’ instead of ceased solar wind. It’s not as if the solar system out at the radius of voyager 1 is much more than ceased solar wind particles. Again you seem to be alluding the absurd, as if the solar system has an intrinsic rigid solid structure against which the interstellar wind can collide with.
And anyway it doesn’t explain the cessation of the solar wind.
Leif,
Thanks for correcting my (mis)understanding of yet another aspect of this universe, the solar magnetics!
But a followup thought/question:
I take it:
1) magnetic flips don’t coincide with a substantial total solar magnetic field presence,so
2) unlike the Earth, the “poles” of the Sun are a separate phenonena to the general magnetic fields of the Sun. From other stuff, then,
3) a descent into a normal, low sunspot “Quiet Sun” period does NOT mean the magnetic character of the Sun necessarily changes, so
4) the magnetic field is NOT strictly related to whatever causes sunspots,
4) the Dalton and Maunder periods in which sunspots were rare or absent was a time in which the magnetic field was ALSO low.
I take it, then, that the magnetic field of the sun is a multi-component phenomena, and it is possible that the magnetic poles of the sun – their presence or absence – may be a collective phenomena. Perhaps an entrainment of smaller portions that happens with either positive reinforcement processes or a simple time varying phase event of various processes with their own cycles.
I’m trying to get my head around how no sunspots this month is not significant, but no sunspots during the Dalton/Maunder, upcoming Cycle 25 IS signficant wrt magnetic field strength. Also how a solar magnetic field can be substantially unchanged while poles come and go IF processes in the Sun are essentially unitary, i.e. one large process spinning off a multitude of secondary events, rather than a multitude of semi-independent events that combine to give the illusion of a “global” process.
The solar magnetic reversal is probably going to occur later rather then sooner and is meaningless when it comes to the climate.
In addition the mainstream scientific commmunity is still trying to convey to the public that the sun is acting normal when the reality is ,it is in a prolonged solar minimum period. The second half of solar cycle 24 maximum is not going to be anything like a maximum in all probability. .
I put very little faith in what the mainstream has to say when it comes to solar predictions.
As recently as year 2007 many were saying solar cycle 24 would be one of the most active solar cycles ever ,instead it has been one of the weakest ever ,which was forecasted way in advance by those who subscribe to the angular solar momentum theory.
The solar parameters will tell the story going forward and nothing else.
Solar flux today 104 in the middle of the so called maximum. Keep wishing.
Solar cycle 24 is as weak as Solar Cycle 5 associated with the Dalton Solar Minimum.
The Layman sunspot count is the ONLY count that gives one a proper perspective on the relative strength of solar cycles.
“but would a person have to get a new compass on the sun when this flip occurs?”
Only if that person lives on the sun.
Clyde says:
August 6, 2013 at 11:27 am
Not to dumb down the comments, but would a person have to get a new compass on the sun when this flip occurs? In other words would north now be south?
The compass would, indeed point to other way [on the Sun, not the Earth].
meemoe_uk says:
August 6, 2013 at 11:30 am
If a spot of irony is half of your rebuttal to my comment then its a pretty weak rebuttal.
No rebuttal as there was not much substance to rebut. Look at it as [free] education. Let me summarize: A year ago, it was found that the solar wind moved a tad slower than thought. Using the models then available McCormack and colleagues computed by simulation that the models predicted no bow shock. A year later, using improved models, the same authors found that a bow shock was likely to form.
Again you seem to be alluding the absurd, as if the solar system has an intrinsic rigid solid structure against which the interstellar wind can collide with.
It does, just like the Earth’s magnetic field is an obstacle for the solar wind to collide with.
And anyway it doesn’t explain the cessation of the solar wind.
When there is a pressure balance between the solar wind and the interstellar medium, the solar wind stops.
Doug Proctor says:
August 6, 2013 at 11:36 am
1) magnetic flips don’t coincide with a substantial total solar magnetic field presence,so
2) unlike the Earth, the “poles” of the Sun are a separate phenonena to the general magnetic fields of the Sun. From other stuff, then,
3) a descent into a normal, low sunspot “Quiet Sun” period does NOT mean the magnetic character of the Sun necessarily changes, so
4) the magnetic field is NOT strictly related to whatever causes sunspots,
4) the Dalton and Maunder periods in which sunspots were rare or absent was a time in which the magnetic field was ALSO low.
No, that chain is incorrect.
It is rather that the poles are the ‘general magnetic field’ which eventually controls the solar cycle. The magnetic field at the poles is the stuff of which sunspot are formed inside the sun. The magnetic field during the Maunder Minimum was likely not very low as there was a strong solar cycle modulation of cosmic rays [caused by the magnetic field].
I’m trying to get my head around …
The polar fields are dragged into the Sun by circulation of material. At depth the magnetic field is amplified by induction. The resulting stronger fields float to the surface and there assemble into sunspots. Sunspots decay and the magnetic debris is carried to the poles and the process repeats. So there is a mixture of global and of small-scale processes.
Salvatore Del Prete says:
August 6, 2013 at 11:41 am
I put very little faith in what the mainstream has to say when it comes to solar predictions.
Because you do not know what the science has to say about that, or how cycle 24 was correctly predicted by mainstream science.
Solar flux today 104 in the middle of the so called maximum.
The past month the solar flux has been around 120, as predicted.
Salvatore Del Prete says:
August 6, 2013 at 12:05 pm
The Layman sunspot count is the ONLY count that gives one a proper perspective on the relative strength of solar cycles.
The Layman sunspot count is junk, uncalibrated, and misconstructed
If one looks at the graphs one can see a major difference with solar north/south polar field changes in this cycle as oppossed to earlier cycles.
Solar cycle 24 is nothing like the typical solar cycles of the last century .
That is your opinion and you are but one person.
Salvatore Del Prete says:
August 6, 2013 at 12:15 pm
If one looks at the graphs one can see a major difference with solar north/south polar field changes in this cycle as opposed to earlier cycles.
Apart from being small, there is no difference.
Solar cycle 24 is nothing like the typical solar cycles of the last century
It is very similar to the low cycles at the beginning of that century.
Salvatore Del Prete says:
August 6, 2013 at 12:16 pm
That is your opinion and you are but one person.
and how many persons are you? perhaps Sharp up to his old tricks?
Doug Proctor says:
August 6, 2013 at 11:36 am
I take it:
4) the magnetic field is NOT strictly related to whatever causes sunspots,
Huhhhhhhhhhh!
Now you really got yourself in a sticky situation.
If Dr. S agrees with that I’ eat my hat.
Strict relation 0.7 Rmax is the basis of his solar hypothesis, and admittedly correct prediction of SC24max
Wrong the solar flux at this stage of solar cycle 24 has been predicted to be north of 140.
Leif ,give us your predictions for solar flux average and ap index average for the rest of year 2013 , and year 2014 and year 2015.
I predict solar flux will be around 110 for the rest of 2013 ,and fall to around 100 in year 2014 and sub 90 by year 2015.
Solar cycle 24 is nothing like the weak solar cycles early this century it is much more like solar cycle 5 of the Dalton Minimum.
Salvatore Del Prete says:
August 6, 2013 at 12:24 pm
Wrong the solar flux at this stage of solar cycle 24 has been predicted to be north of 140.
Slide 37 of http://www.leif.org/research/Predicting%20the%20Solar%20Cycle%20%28SORCE%202010%29.pdf
Leif ,give us your predictions for solar flux average and ap index average for the rest of year 2013 , and year 2014 and year 2015.
120, 120, 115; 10, 9, 12
I predict Leif won’t predict. I hope I am wrong.
Fair enough 120,120 and 115 ap index 10,9,12. I will save this prediction and we will see how correct or wrong it is. Thank You for the prediction.
WUWT solar reference page clealry shows on the solar flux graph that the smooth average for the solar flux at this stage of sola rcycle 24 was forecasted to be slightly above the 140 level. It can not be any clearer.
Salvatore Del Prete says:
August 6, 2013 at 12:28 pm
Solar cycle 24 is nothing like the weak solar cycles early this century it is much more like solar cycle 5 of the Dalton Minimum.
Apart from the fact that the sunspot data we have for cycle 5 is very uncertain so no meaningful comparison can be made; which of these curves do you wish to compare with http://www.leif.org/research/Wolf-SSN-for-SC5.png
Salvatore Del Prete says:
August 6, 2013 at 12:37 pm
WUWT solar reference page clealry shows on the solar flux graph that the smooth average for the solar flux at this stage of solar cycle 24 was forecasted to be slightly above the 140 level. It can not be any clearer.
That forecast was a political compromise [not science] and is not correct. [too high]. I have already given you my forecast: Slide 37 of http://www.leif.org/research/Predicting%20the%20Solar%20Cycle%20%28SORCE%202010%29.pdf and the reasons for it.
Re: “It is time for you to take your ball and go home rather than try to play with the big boys.”
Question for WUWT: Where was your moderator with “SNIP”? Why wouldn’t you want to save Dr.S from making such a statement! It adds nothing to Science, and only reflects on his character. If the person was wrong, why isn’t it enough just to say so. Why denigrate him in the process?
Unfortunately, I have observed this type of remark too many times in the past.
The coming years are going to tell us much.
How amazing is it to have a solar scientist like Leif come on this site and answer so many questions!!! Thanks Leif! Wattsupwiththat rocks.