Solar Cycle 24 Main Discussion IX

[af4ex]

The specks are just indicators of high magnetic activity, not the aftermath of the flare. Very likely were there before the flares started from that part of 1147.

It is remarkable (to me at least) how different the region looks in the different wavelenths.

Here's how 1147 looked (below) at VHF and UHF wavelengths yesterday. We're actually seeing here the synchrotron radiation from charged particles 100,000km or higher above the region. Much lower resolution at these much longer wavelengths so you can't see as much detail.

Note how the pattern shifts westward at 150Mhz at the very same instant. Probably parallax effect due to the radiation coming from much higher above the photosphere. My understanding is that the VHF effect extends further out because it represents slower acceleration of the particles streaming along the field lines of 1147.

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[bradk]

Very interesting. Thanks for bringing us newbies along...

Are the other wavelength outputs changing with the L & P effect are is this separate? OR has anyone looked?

[af4ex]

Jan 21, 2011 14:59:43 GMT bradk said:

Very interesting. Thanks for bringing us newbies along...

Are the other wavelength outputs changing with the L & P effect are is this separate? OR has anyone looked?

I'm just a neophyte myself, but have learned a lot, since last March, by listening to Leif and the other experts on board here.

The primary thesis of the L&P effect is that the average magnetism of sunspots has been declining for over a decade.

Since the darkness ('contrast') of the spots depends how much their magnetism exceeds 2500 Gauss, the visible parts of the sunspots have also been fading in proportion to this magnetic decline.
[Edit: that should read 1500 Gauss, not 2500]

So any phenomenology that depends on the intensity of the magnetism in these active regions may also be affected. But I don't think L&P (Livingston and Penn) have made any specific claims in this area. Perhaps Dr. S. could elaborate on this.

But in general people tend to overestimate the impact of this effect because they think the sunspots (aka active regions) are totally shutting down. That's clearly not the case because you can see these regions operating in other wavelengths, which our eyes can't see. The regions are still there, very active magnetically, even if you can't see them directly with your eyeballs.

That's why I spend so much time looking at microwave, EUV and x-ray emissions. The energies radiated at these extremal wavelengths are miniscule compared to the total radiance, which peaks in the visible wavelengths. But they are very good indicators of what's happening in and above the active regions.

[af4ex]

Whoa. Look at all the new x-ray activity today. All of it ascribed by NOAA/USAF to region "1149", which won't get officially announced for a few more hours, which will be posted here:
www.swpc.noaa.gov/ftpdir/latest/SRS.txt

Comparing 1149 to 1147, visually, you wouldn't suspect it that 1149 is a much more active region. In EUV light it's hard to tell that 1149 is a separate enterprise.

What are the rules for classifying new regions that are spin-offs of nearby regions? (And have I correctly segmented them below? 1147 seems to have many invisible parts in the continuum image)

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[bradk]

Very true, but if the sunspots are visible because of the magnetism above 2500 Gauss, is it not also possible that the changes in magentism at these sun-specks are also causing outsput changes at other wavelengths as the megnetism changes because of the L & P effect?

[af4ex]

Jan 21, 2011 21:44:37 GMT bradk said:

Very true, but if the sunspots are visible because of the magnetism above 2500 Gauss, is it not also possible that the changes in magentism at these sun-specks are also causing outsput changes at other wavelengths as the megnetism changes because of the L & P effect?

"Sunspots" are not real objects in the sense that they represent the relative absence of light flux welling up from the photosphere. The magnetic fields tend to block the light from reaching the surface, so it looks relatively darker.

In absolute terms sunspots are blindingly bright, brighter than the light from an arc welder. But the surrounding photosphere is even brighter, so they look dark in comparison.

Other types of emissions, such as x-rays and microwaves are generated in the chromosphere, or higher, by acceleration of charged particles (e.g. electrons bumping into protons etc). Magnetism has a different effect on these processes, Zeeman splitting, bremstrahlung, gyro-frequencies etc., which don't attenuate the radiation, but shift it around or cause it to be generated from kinetic energy.

The main part of the sun's radiance is in the visible spectrum, which is where we see the sunspots, IR and UV. The other, extremal wavelengths (x-ray,EUV, RF) contribute a very tiny part to the total radiation output.
en.wikipedia.org/wiki/File:Solar_Spectrum.png

So, yes, the declining magnetism may affect other solar processes which depend on magnetism, but it won't necessarily be manifested as declining intensities.

(Dr. Svalgaard, did I get that right?)

[bradk]

Thanks again.

I never meant to imply any other changes would also be negative, but that they may exist and likely do. This is our first shot at an up close and personal with a minima, maybe a grand one, and I think we can expect alot learnings if scientists dare to ask the hard question and challenge the norm.

[af4ex]

bradk
> I never meant to imply any other changes would also be negative

I forgot to mention that the 10.7cm radio flux doesn't seem to be affected by the L&P effect.

Historically SSN and SFI have been strongly correlated. But since the mid 1990's the SSN/SFI correspondence has been sagging: because sunspots are fading because of L&P, but SFI is not affected.
www.leif.org/research/F107%20and%20SSN.png

Dr. Svalgaard pointed out a few weeks ago that the SFI can be reconstructed back into the 19th century using diurnal changes in geomagnetism as a proxy. (page 40, reply #599 & ff.). These reconstructions offer no evidence of any previous "L&P effect" going back to about 1840, which includes Cycle 14, thought to be a prototype for SC24.

So this current "grand minimum" may be a completely different ball game, with its own peculiar rules.

[bradk]

True, and great point. The real question I guess is since we have had nothing like this in the modern era, and now we have more instruments than ever, how much will we learn and how many "truths" will be overturned by the time we finish? If it is anything like the human genome project, the world of solar science will be on its head...

[lsvalgaard]

Jan 22, 2011 1:48:22 GMT bradk said:

Thanks again.

I never meant to imply any other changes would also be negative, but that they may exist and likely do. This is our first shot at an up close and personal with a minima, maybe a grand one, and I think we can expect alot learnings if scientists dare to ask the hard question and challenge the norm.

all scientists dare ask hard questions and challenge the norm. This is what scientists do for a living [if not, they are not scientists].

[bradk]

Dr. Svalgaard-

I would agree with you, but in a day and age where some scientists are busy trying to use science to influence politics and some funding agencies are sometimes busy funding only the safe science and worried about "failed grants" if they take on too much risk, I guess we have an era where some science is safe or otherwise motivated. Maybe I, like you, should make it easy and just not call those scientists.

My thought was clearly not aimed at you or Livingston and Penn or lots of other great minds out there. I was more thinking of the peer review system that can be used to suppress new ideas or stop publication of new ideas by those that would question the codified norm.

[bradk]

af4ex-

Looks like you may be right once again, the backside is warming up on STEREO.

[af4ex]

I guess those bureaucrats at NOAA/USAF really don't work on weekends. They still haven't updated their Solar Region Summary to include 1149:
www.swpc.noaa.gov/ftpdir/latest/SRS.txt
:Product: Solar Region Summary
:Issued: 2011 Jan 21 0030 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Solar Region Summary
SRS Number 21 Issued at 0030Z on 21 Jan 2011
Report compiled from data received at SWO on 20 Jan
I.  Regions with Sunspots.  Locations Valid at 20/2400Z
Nmbr Location  Lo  Area  Z   LL   NN Mag Type
1147 N24E09   342  0170 Cso  09   09 Beta
1148 S28W72   063  0020 Bxo  02   03 Alpha
IA. H-alpha Plages without Spots.  Locations Valid at 20/2400Z Jan
Nmbr  Location  Lo
1146  N23W84   076
II. Regions Due to Return 21 Jan to 23 Jan
Nmbr Lat    Lo
1139 S27    236


1149 produced another big C-flare followed by a mid-sized B a few hours ago. Its sunspot eye is forming rapidly and is almost as big as 1147's.

But visible light doesn't really accurately portray the real physical extent of these two regions. Most of 1147 is hidden from the eye, including the very bright EUV emissions on its East end.

Magnetically both regions have very strong magnetism on the western sides, collocated with the visible spots of course. But there is a great deal of magnetic activity which the eye can't see.

In this "triple view" below I tried to capture the "real" essence of these two regions, in multiple wavelengths: Visible, ExtremeUltraViolet and Magnetogram, all captured from SDO's superb public image gallery:

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[bradk]

Thanks for your good work af4ex! I ued to go to solen.info for her spot comparisons, but I love your multiple wavelength take on spots.

[af4ex]

Jan 22, 2011 13:18:18 GMT bradk said:

Thanks for your good work af4ex! I ued to go to solen.info for her spot comparisons, but I love your multiple wavelength take on spots.

Thanks. I think we all spend too much time counting and arguing about sunspots. A "hyperspectral" approach is much more enlightening, IMHO, about what's going on under the solar hood.

... here's two more. These two regions are also very bright (and different looking) in 17Ghz microwave and 1-8 angstrom x-rays. 1149 is noticeably brighter and dynamic in microwaves and has been doing all of the 'heavy lifting' in the x-ray flare dept for the past two days.

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