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:
Related articles
- The solar cycle is still slumping (wattsupwiththat.com)
- Sun’s 2013 Solar Activity Peak Is Weakest in 100 Years (space.com)
Salvatore Del Prete says:
August 6, 2013 at 12:47 pm
The coming years are going to tell us much.
One can hope that you will learn.
To my knowledge the longest interglacial periods (super-interglacials) during this ice age last little more than 30,000 years. I find it hard to believe that our current interglacial will last anywhere near 50,000 years, let alone the 30,000 years in total seen during the few super-interglacials.
If I remember correctly these super-interglacials exhibited sea levels of 25+ m higher than today, evidence that the Greenland and Antarctic Ice Sheets were diminished. Other proxy data supports this. Today our climate is slightly cooler and sea level is slightly lower than during the optimums of the previous four interglacials. Arctic sea-ice has yet to diminish to the levels suggested from the data of the previous interglacials as well. So, to me the data suggests that our current climate is no different than any normal interglacial but change is the only thing that’s consistent so it’s not impossible that this interglacial will be substantially longer than all the previous ones.
Sam Glasser says:
August 6, 2013 at 12:43 pm
If the person was wrong, why isn’t it enough just to say so. Why denigrate him in the process?
You may have overlooked this denigration:
meemoe_uk says:
August 6, 2013 at 8:32 am
“Typical. Leif is not being honest about evidence in relation to solar wind bow shock ”
You give, you get back.
Leif Svalgaard says:
August 6, 2013 at 12:37 pm
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
How about cosmogenic isotope data? Do you find this data too unreliable?
Robert W Turner says:
August 6, 2013 at 1:02 pm
I find it hard to believe that our current interglacial will last anywhere near 50,000 years, let alone the 30,000 years in
The proper way to deal with this is to show the mistake or weakness in Berger & Loutre’s paper rather than basing your belief on incredulity.
Robert W Turner says:
August 6, 2013 at 1:08 pm
How about cosmogenic isotope data? Do you find this data too unreliable?
Judge for yourself: http://www.leif.org/research/Solar-Activity-1785-1810.png
The cosmic ray data is interpolated from [if memory serves] 5-yr samples. And it is hard to calibrate that into sunspot numbers to compare with.
Well … we can hope that we all learn a lot.
I’m holding my breath to see if temperature actually goes down as Archibald has predicted. Granted, as Leif has said in the past, …. it doesn’t prove the sun is controlling climate .. but it’ll dang sure show that CO2 is not controlling climate, and put an end to all this hub bub about boiling planet, dying polar bears and flooded coast.
And Hey .. maybe there is a yet to be discovered mechanism of how the sun controls atmospheric circulation and clouds, such that it does in some way influence the amount of SW that reaches the surface, which is a completely separate issue from TSI.
Leif Svalgaard says:
August 6, 2013 at 1:10 pm
Robert W Turner says:
August 6, 2013 at 1:02 pm
I find it hard to believe that our current interglacial will last anywhere near 50,000 years, let alone the 30,000 years in
The proper way to deal with this is to show the mistake or weakness in Berger & Loutre’s paper rather than basing your belief on incredulity.
Well I based this on thinking that an interglacial of that length had never occurred before but upon further research I found that one interglacial, MS 11, did last that long.
Leif,
How does this HCS relate to space-time? Do the planets pass through the sheet or does the sheet contour with space-time? No pun intended.
TLMango says:
August 6, 2013 at 1:26 pm
How does this HCS relate to space-time? Do the planets pass through the sheet or does the sheet contour with space-time? No pun intended.
Nothing that fancy. The HCS is just a thin sheet of current caused by charges drifting in the magnetic field. The density is higher there than away from the current. So it is a real physical thing. The HCS is tied to the Sun so as the Sun rotates the current sheet will rotate with it and will sweep over the planets. It will sweep over the much slower moving Earth some 13 to 14 times in a year.
Hey Leif .. back to my question about the butterfly chart.
I can’t help but notice that it steadily increases and remains pretty dang strong after 1960, even cycle 20 is pretty dang strong compared to earlier cycles. Has anyone ever quantified this effect in a line graph, and seen how it correlates to climate?? [yeah .. still searching 🙂 ]
I’m wondering how far back does knowledge of the various sun cycles, magnetic, sun spot, flux etc. go. Is it mostly derived from modern observations (e.g. since the invention of the telescope and electronics). Is there any data from further back in the Holocene, from the 100k glaciation cycle, from the 40k glaciation cycle, from before the glaciations etc? How do we know these sun cycles endure. How do we know they weren’t radically different in the distant past or even just the pre-historic past? If we’re limited to information from our little part of the Holocene how do we know sun cycles don’t play a much larger role in earth’s climate?
Leif Svalgaard asks “an alternate URL?”
Dr. Deanster gave an IP address, not a URL. This works:
http://www.nwu.ac.za/webfm_send/42735
NWU neutron monitor graphs:
http://www.nwu.ac.za/neutron-monitor-data
Leif Svalgaard says:
August 6, 2013 at 1:34 pm
The HCS is tied to the Sun so as the Sun rotates the current sheet will rotate with it and will sweep over the planets.
I think the above is open to misinterpretation, you might wish to clarify.
Dr. Deanster says:
August 6, 2013 at 1:35 pm
I can’t help but notice that it steadily increases and remains pretty dang strong after 1960, even cycle 20 is pretty dang strong compared to earlier cycles. Has anyone ever quantified this effect in a line graph
Yes, many times, e.g. http://www.leif.org/EOS/1108-1722v1Hathaway-Sunspot-Law.pdf
and seen how it correlates to climate?? [yeah .. still searching 🙂 ]
It doesn’t.
John G. says:
August 6, 2013 at 1:35 pm
I’m wondering how far back does knowledge of the various sun cycles, magnetic, sun spot, flux etc. go. Is it mostly derived from modern observations (e.g. since the invention of the telescope and electronics). Is there any data from further back in the Holocene, from the 100k glaciation cycle
We have cosmic ray procies going back about 10,000 years. Before that, the variations due to glaciations [due to planetary perturbations of our orbit] are so huge that any solar signal [which we don’t have as yet] would be completely lost in the noise.
nutso fasst says:
August 6, 2013 at 1:36 pm
This works: http://www.nwu.ac.za/webfm_send/42735
Thanks, unfortunately I still have to do a two-step thing to get to the larger image.
link:
http://iswa.gsfc.nasa.gov/IswaSystemWebApp/iSWACygnetStreamer?timestamp=2038-01-23+00%3A44%3A00&window=-1&cygnetId=261
vukcevic says:
August 6, 2013 at 1:41 pm
The HCS is tied to the Sun so as the Sun rotates the current sheet will rotate with it and will sweep over the planets”
I think the above is open to misinterpretation, you might wish to clarify.
What is there to misinterpret? My statement is precise, true, and simple. Here is nice animation: http://iswa.gsfc.nasa.gov/IswaSystemWebApp/iSWACygnetStreamer?timestamp=2038-01-23+00%3A44%3A00&window=-1&cygnetId=261
vukcevic says:
August 6, 2013 at 1:52 pm
link
So?
Leif Svalgaard says:
August 6, 2013 at 1:55 pm
vukcevic says:
August 6, 2013 at 1:41 pm
The HCS is tied to the Sun so as the Sun rotates the current sheet will rotate with it and will sweep over the planets”
I think the above is open to misinterpretation, you might wish to clarify.
What is there to misinterpret? My statement is precise, true, and simple. Here is an even nicer animation: http://www.youtube.com/watch?v=2434rAbImf0
vukcevic says:
August 6, 2013 at 1:41 pm
“The HCS is tied to the Sun so as the Sun rotates the current sheet will rotate with it and will sweep over the planets”
I think the above is open to misinterpretation
How do you misinterpret it?
Let’s assume that an ‘observing imaginary object’ is ejected from the sun approximately at 13o’clock position, coinciding with line denoted 24 in red (see links above) sitting on the expanding dark blue blob.
‘observing imaginary object’ always travels radially from the sun, not rotating with it.
Just sayin’, but I am sure you’ll come up with something to show that ain’t so. .
vukcevic says:
August 6, 2013 at 2:20 pm
‘observing imaginary object’ always travels radially from the sun, not rotating with it.
The individual solar wind particles always travel radially away from the Sun but the HCS is a structure and that structure rotates with the Sun as shown here http://www.youtube.com/watch?v=2434rAbImf0
The situation is like a wave rolling over the ocean. The structure moves forward, the water molecules [or a boat in the water] does not. A tsunami is not a wave, it is a actually a ‘bore’ and in that the water actually moves forward, making tsunamis so powerfully dangerous. You can liken a CME to a tsunami.
Any other misinterpretations you want corrected?
There you are, now everyone can see why ‘things’ that travel in a strait line appear to rotate.
So we have probably hit the max for the current cycle.
vukcevic says:
August 6, 2013 at 2:52 pm
There you are, now everyone can see why ‘things’ that travel in a strait line appear to rotate.
No, that is a misinterpretation. The ‘things’ don’t rotate, the structure [the HCS] does. And it does not ‘appear’ to rotate, it actually does rotate.