While sunspots are often cited as the main proxy indicator of solar activity, there is another indicator which I view as equally (if not more) important. The Average Planetary Magnetic index (Ap), the strength of which ties into Svensmark’s cosmic ray theory modulating Earth’s cloud cover. A weaker Ap would mean less cosmic rays are deflected by the solar magnetic field, and so the theory goes, more cosmic rays provide more seed nuclei for clouds in Earth”s atmosphere. More clouds mean a greater albedo and less terrestrial solar radiation, which translates to lower temperatures.
I’ve always likened a sunspot to what happens with a rubber band on a toy balsa wood plane. You keep twisting the propeller beyond the normal tightness to get that extra second of thrust and you see the rubber band start to pop out knots. Those knots are like sunspots bursting out of twisted magnetic field lines.
The Babcock model says that the differential rotation of the Sun (the sun being a viscous fluid, the poles rotate at a slower rate than the equator) winds up the magnetic fields of it’s layers during a solar cycle. The magnetic fields will then eventually tangle up to such a degree that they will eventually cause a magnetic break down and the fields will have to struggle to reorganize themselves by bursting up from the surface layers of the Sun. This will cause magnetic North-South pair boundaries (spots) in the photosphere trapping gaseous material that will cool slightly. Thus, when we see sunspots, we are seeing these areas of magnetic field breakdown.
Sunspots are cross connected eruptions of the magnetic field lines, shown in red above. Sometimes they break, spewing tremendous amounts of gas and particles into space. Solar flares and coronal mass ejections (CME’s) are some examples of this process. Sometimes they snap back like rubber bands. The number of sunspots at solar max is a direct indicator of the activity level of the solar dynamo.
As many of you may recall, a few months ago, I had plotted the Average Geomagnetic Planetary Index (Ap) which is a measure of the solar magnetic field strength but also daily index determined from running averages of eight Ap index values. Call it a common yardstick (or meterstick) for solar magnetic activity.
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I’ve updated the graph today, to include July 2008 Ap data as you can see below:
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Source data, NOAA Space Weather Prediction Center:
http://www.swpc.noaa.gov/ftpdir/weekly/RecentIndices.txt
As you can see, the Ap Index has continued along at the low level (slightly above zero) that was established during the drop in October 2005. As of July 2008, we now have 34 months of the Ap hovering around a value between 5 to10, with occasional blips of noise.
Since it is provided in the same dataset, I decided to also plot the smoothed Ap Index.
I also plotted my own 24 month smoothing window plot, shown in magenta.
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I also decided to update the plot of the 10.7 centimeter band solar radio flux, also a metric of solar activity. It is in the same SWPC dataset file as the Ap Index, in columns 8 and 9. The smoothed 10.7 CM flux value provided by SWPC has also dropped about the same time continues a downward trend.
I also provided my own 24 month wind smoothed value which is plotted in magenta.
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Note the lower flux values during this solar minimum than the last
We continue to remain in a deep solar minimum, and with the forecasts being modified to push back the real “active” start of Solar cycle 24, it remains anybody’s guess as to when the sun will come out of it’s funk.
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statepoet 775/ Lucy Skywalker
I would think that our solar systems travels through space would have more to do with the suns behavior and ultimately our climate than the current science accounts for.
We ( the solar system) are traveling through space and minute by minute are influenced by forces that have yet to be realized, we are not stationary but traveling through space and are continually entering and leaving other terrestrial bodies sphere of influence, to give some idea to the problem, sprinkle some iron filings on a glass top table, then try and predict the form they will take after you pass a magnet under the table at various speeds and distances.
Leif, I appreciate the difference between what the Sun is doing objectively, and what we see/measure on Earth. That is why so many are working on sending instruments towards the Sun, so we can measure it outside of the relativity created by Earth. Makes sense.
I also see the other side of this discussion. If what we want to measure is our Earth’s interaction with what the Sun is doing, we would want to measure things from Earth’s perspective. That is why so many are working on sending instruments towards our atmosphere to measure CO2, ozone, cosmic rays, UV, etc, as well as here on the ground.
Climatologists need objective information about the Sun. But they also need that same information as it travels through our atmosphere so that they can hypothesize theoretical constructs and test them in the lab. I believe rudimentary cloud chambers tried this and now these scientists are on to bigger chambers.
Two separate scientific fields of inquiry. I get it. The argument for or against adjusted TSI falls due to the cross purposes of the data in question. One side is arguing for apples, the other side oranges, and the apple group is insisting that you, the orange group, measure the Sun from Earth so that we can all be happy apples. I can see that you want information about the Sun, regardless of what planet you are standing on. I can see that the apple group wants data about the Sun that is measured through Earth so that we can continue the discussion of the Sun’s influence on our climate.
Lief:
I’m chuckling. On another blog I made the argument a few days ago that if you couldn’t trust one piece of evidence, then it caused all other evidence of a similar nature to be questionable as well. I was told by a scientist that my argument was very “anti-scientific.” The issue at hand was videos, and I pointed out that if one video was proven to have been faked, then one should be skeptical of all other videos on the subject.
The ‘scientist” insisted that this was not science and that indeed each video should be proven to be legitimate or a fake, and that was the scientist’s job to be skeptical of all and prove the validity or invalidity of each one.
Oh well. I can’t win.
Ranting Stan (00:07:37) :
why 200 by the way?
Because the typical speed is 20 m/s and the typical length is 10 years: 20*10=200
Lucy Skywalker,
It isn’t a controversial issue, it really is a non-issue. However, I do beleive it is understandable that you may feel that there is something to it.
The best way to investigate is to solve the GR equations and show yourself the extra forces do not exist. If your math skills are not up to the task, ask someone who has solved them and (provisionally) accept their answer until you develop the skill to show yourself.
Pamela Gray (07:44:02) :
The argument for or against adjusted TSI falls due to the cross purposes of the data in question.
It is simpler than that. Both raw and adjusted data are equally available, you pick the one that fits your purpose. If your purpose is to point out how quiet the Sun is, you pick the Sun-centered one.
David G. Mills (07:59:40) :
I’m chuckling. On another blog I made the argument a few days ago that if you couldn’t trust one piece of evidence, then it caused all other evidence of a similar nature to be questionable as well.
What interests me is if my was compelling for you.
The ’scientist” insisted that this was not science and that indeed each video should be proven to be legitimate or a fake, and that was the scientist’s job to be skeptical of all and prove the validity or invalidity of each one.
There is some truth to this as well. For the case at hand, my comment showed a lack of basic scientific understanding and that carries over to all the rest.
Oh well. I can’t win.
Well, if you accept the strong plausibility that the paper was indeed bunk, then we both win.
Ranting Stan (00:07:37) :
If, as you say, this is how they determine the strength of the next solar cycle – or one of the factors – then I suppose the question should be – what is the conveyor doing now and if they have stopped measuring it post 2003 – then why?
I would like to know this too. I guess that I could investigate for myself [the data is publicly available], but your guess that a lack of spots makes it hard is a good one. Certainly, the sunspot method would not give meaningful results for 2007-2008.
Anthony
I am writing a paper for my website about the Sun’s influence on global climate. You produce some of the finest charts that can be found on the web. Do you permit copying and use of your charts with attribution to you? I would like to use your chart the sun’s geomagnetic activity and your chart of UAH global temperature since 79.
Chuck D
REPLY: Thanks for the kind words, copy at will. -Anthony
credit: Anthony Watts, http://www.wattsupwiththat.com
Raphael, maybe you are right, maybe it’s a non-issue. But my curiosity is now aroused! Scuse my ignorance but what is GR? Galactic Rotation or General Relativity? And BTW, quantum theory trumps Einstein and then its zero point field proves the truth of both e=mc2 and f=ma (Newton).
Lucy Skywalker,
GR = General relativity. I used both in my first reply to you. I’ll make sure to be more specific in the future.
I never said to ignore the issue because it is a non-issue. I said solve the equations and prove it to yourself. Curiosity is good. Blind faith is bad.
[…] “The Sun remains in a magnetic funk“, Anthony Watts, posted at his blog Watts Up with That, 30 August 2008: […]
“I know, I cannot assume that everyone is versed in elementary science, and that it is our duty as scientists to provide the public with the information it deserves, one would recommend a little bit of restraint on your part when you are that far off the mark.”
Indeed, I was off the mark; the radio flux is comprised of bosons after all.
The lapse is quite like that of your own detailing the consequence of tidal forces:
“and the gravitational forces are precisely balanced by centrifugal forces. This is easiest seen for the case of two stars with equal masses in large circular orbits…Both stars will continue to circle forever ”
Of course, the orbit must decay (and the stars eventually coalesce) by gravitational quantum mechanics.
I allowed at the time you were “confused”. A bit more measured response, ya’ think?
[…] That’s understandable I suppose, still I really wanted to ask what they though about the step function in the Ap Index that occurred in October 2005 and has remained flat […]