Jump to content
theartist

Ap & aa Indices and Solar Minimum

Recommended Posts

On 12/5/2019 at 2:27 PM, Jenn said:

Also, shouldn’t Voyager 1 be able to tell us by now what the local interstellar cloud is like in more detail?

Here is an article discussing a probe's relatively recent interactions with interstellar medium, including a paper citation:   http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20191202

I find it somewhat questionable, on first blush, regarding their claim that solar EM radiation is ionizing incoming particles 'way out there'; interesting. 

  • Thanks 1

Share this post


Link to post
Share on other sites

TAG, 

You might want to take a look at the following graph:

532485695_ScreenShot2019-12-11at4_06_33AM.thumb.png.2b45cee83deb5b1613ad9f01a3aacb3e.png

(Source of graph).

In addition to the prolonged dip of the South, look at the double-dip of the North.  Does this graph convince us we are in an unusual Solar Minimum?

---------------------       -------       ---------------------

Folks, I just came across a piece of information that is quite interesting! I say that after all of my work and study of spaceweather, particularly heliophysics, over the past several months, which has helped bring me to the point where I can now understand this newly provided information, and appreciate it for what it is.  After seeing this information, I now understand that the interpreting of "polar fields" (which is an important subject in solar cycle activity forecasting) may need to be done in a manner different than how I've been doing it up to now.  

The information I wish to share is a link to a video of a presentation by the author of the paper I cited above, Alexander G. Kosovichev. His presentation starts at 24:44 into the following video:   https://www.youtube.com/watch?v=Gvj8xwOe0e8&t=1484s .

Thank-you for all of your kind words over these past several months, and a special thank-you to spaceweatherlive.com for allowing me to share my journey into heliophysics with you all.

P.S. To Irene, I suspect you will enjoy the message that follows the one given by Dr. Kosovichev. ☺️

Edited by theartist

Share this post


Link to post
Share on other sites
10 hours ago, theartist said:

Here is an article discussing a probe's relatively recent interactions with interstellar medium, including a paper citation:   http://pluto.jhuapl.edu/News-Center/News-Article.php?page=20191202

I find it somewhat questionable, on first blush, regarding their claim that solar EM radiation is ionizing incoming particles 'way out there'; interesting. 

Thank you for the link.
I went back to my research ten years ago and compared what I was 🤔  contemplating to what we know today. I’m still “feeling” this is the calm before the storm. I’d be interested to know what your views are regarding my research. I can link you to the forum if you don’t mind reading an amateur type of research. 😂 

Also, saw this yesterday and I think the last sentence says it all. 

“ Our Sun may exit the Local Cloud, also called the Local Fluff, during the next 10,000 years. Much remains unknown about the local ISM, including details of its distribution, its origin, and how it affects the Sun and the Earth. Unexpectedly, recent IBEX spacecraftmeasurements indicate that the direction from which neutral interstellar particles flow through our Solar System is changing” 

https://apod.nasa.gov/apod/ap130924.html

 

 

  • Thanks 1

Share this post


Link to post
Share on other sites

This certainly does reinforce the idea that something very different is happening; North and South seem to be unusually far out of step, perhaps increasingly so since around 2002/3. The peaks of SC24 differing significantly and now apparently a very different bottoming. Will South stay zeroed until North achieves that bottom level or do its own thing? If it does stay flat, that could give us the long, extended minimum that has been predicted.

1500175732_helioStitched-17.jpg.6b480c14829c212a811589967e79b894.jpg

I took the liberty of stitching together the two parts of your chart to get an overall visual impression of the data. Added to your ideas, one can see that higher latitude activity seems much reduced and more diffuse SC24 compared to SC23, again reinforcing the idea of possible dynamo related activity reducing overall turbulence.

Combining these two concepts, plus the changes we have already discussed, should imply a change of base-line state – but that is pure speculation.

Can I take this opportunity of wishing Seasons Greetings to all, and very best wishes for the New Year and indeed, the New Decade !

 

 

  • Like 2

Share this post


Link to post
Share on other sites
17 hours ago, Jenn said:

Also, saw this yesterday and I think the last sentence says it all. 

Nice, timely article.  However, from the article, look at the timescales being talked about in order to enact perceptible change, "Our Sun may exit the Local Cloud, also called the Local Fluff, during the next 10,000 years. "

As I expect, the article implies real-world effects will require glacial-scale time-periods in order to discern any effects upon our star, and any significant perturbations that would have an effect on our star, in shorter human-lifetime-scale epochs, should (probably) be large enough to be recognized up by our satellite sensors.

17 hours ago, Jenn said:

I can link you to the forum if you don’t mind reading an amateur type of research.

I would not mind taking a look at it, so you can post the link here, or private message me if you wish to limit outside traffic to it.

-------------------------------        -------------------       -------------------------------

13 hours ago, The Atmosphere Guy said:

Added to your ideas, one can see that higher latitude activity seems much reduced and more diffuse SC24 compared to SC23, again reinforcing the idea of possible dynamo related activity reducing overall turbulence.

TAG, I'm not sure how many years you have been at your research, and how long it has included investigating solar effects, so you may or not be aware of what may be a critical puzzle piece of background info.  Evidently, there were a couple of press conferences by some helioseismologists, one in 2009, and one in 2011, pertaining to the things you are pointing out in your 'stitched-together' graph.  

(1) The first press conference was assembled to provide an explanation for why the sunspots were delayed in showing up at the start of Cycle 24.  Here are some details:

"Mystery of the Missing Sunspots, Solved?  June 17, 2009: ...At an American Astronomical Society press conference today in Boulder, Colorado, researchers announced that a jet stream deep inside the sun is migrating slower than usual through the star's interior, giving rise to the current lack of sunspots." https://science.nasa.gov/science-news/science-at-nasa/2009/17jun_jetstream

(2) The later press conference in 2011 was assembled to announce that, based on further helioseismology studies in concert with other observations, there may not even be a Solar Cycle 25:  

"Major Drop in Solar Activity Predicted... Press Release From: National Solar Observatory.  Posted: Tuesday, June 14, 2011...As the current sunspot cycle, Cycle 24, begins to ramp up toward maximum, independent studies of the solar interior, visible surface, and the corona indicate that the next 11-year solar sunspot cycle, Cycle 25, will be greatly reduced or may not happen at all." "This is highly unusual and unexpected," Dr. Frank Hill, associate director of the NSO's Solar Synoptic Network, said of the results. "But the fact that three completely different views of the Sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation." 

4_hill_shearBelowSurface-625x349.jpg.2f80356d3f32c2635a5b0263501d3e36.jpg 

http://www.spaceref.com/news/viewpr.html?pid=33826

Edited by theartist

Share this post


Link to post
Share on other sites

I just noticed that the linked article I provided for the (2) 'press conference' of 2011 does not mention a 'press conference'.  But my research did find other articles on the topic in which there evidently was an official media release and 'press conference', like the following link:

https://www.skyandtelescope.com/astronomy-news/is-the-sunspot-cycle-about-to-stop/       "In a press conference Tuesday morning (June 14th) they predicted that the current solar Cycle 24, which began about three years ago, will produce only half as many spots as the previous one. And, said Frank Hill of the National Solar Observatory, Cycle 25 "may not actually happen." "At the press conference, the researchers explained the three suspicious signs."  

The 'media release' may have since been removed from the net, but with some research, one can still find it, which reads as follows:

 

Contacts:
Dave Dooling
NSO Education and Public Outreach
+1 575-434-7015 (office); +1 575-921-8736 (cell)
dooling@nso.edu

Craig DeForest
AAS/SPD Press Officer
+1 303-641-5679 (cell)
deforest@boulder.swri.edu

Text & Images (after the embargo expires):
http://www.boulder.swri.edu/~deforest/SPD-sunspot-release
(Media teleconference information at bottom of this release.)

WHAT’S DOWN WITH THE SUN?
MAJOR DROP IN SOLAR ACTIVITY PREDICTED

A missing jet stream, fading spots, and slower activity near the poles say
that our Sun is heading for a rest period even as it is acting up for the
first time in years, according to scientists at the National Solar
Observatory (NSO) and the Air Force Research Laboratory (AFRL).

As the current sunspot cycle, Cycle 24, begins to ramp up toward maximum,
independent studies of the solar interior, visible surface, and the corona
indicate that the next 11-year solar sunspot cycle, Cycle 25, will be
greatly reduced or may not happen at all.

The results were announced at the annual meeting of the Solar Physics
Division of the American Astronomical Society, which is being held this week
at New Mexico State University in Las Cruces:
http://astronomy.nmsu.edu/SPD2011/

“This is highly unusual and unexpected,” Dr. Frank Hill, associate director
of the NSO’s Solar Synoptic Network, said of the results. “But the fact that
three completely different views of the Sun point in the same direction is a
powerful indicator that the sunspot cycle may be going into hibernation.”

Spot numbers and other solar activity rise and fall about every 11 years,
which is half of the Sun’s 22-year magnetic interval since the Sun’s
magnetic poles reverse with each cycle. An immediate question is whether
this slowdown presages a second Maunder Minimum, a 70-year period with
virtually no sunspots during 1645-1715.

Hill is the lead author on one of three papers on these results being
presented this week. Using data from the Global Oscillation Network Group
(GONG) of six observing stations around the world, the team translates
surface pulsations caused by sound reverberating through the Sun into models
of the internal structure. One of their discoveries is an east-west zonal
wind flow inside the Sun, called the torsional oscillation, which starts at
mid-latitudes and migrates towards the equator. The latitude of this wind
stream matches the new spot formation in each cycle, and successfully
predicted the late onset of the current Cycle 24.

“We expected to see the start of the zonal flow for Cycle 25 by now,” Hill
explained, “but we see no sign of it. This indicates that the start of Cycle
25 may be delayed to 2021 or 2022, or may not happen at all.”

In the second paper, Matt Penn and William Livingston see a long-term
weakening trend in the strength of sunspots, and predict that by Cycle 25
magnetic fields erupting on the Sun will be so weak that few if any sunspots
will be formed. Spots are formed when intense magnetic flux tubes erupt from
the interior and keep cooled gas from circulating back to the interior. For
typical sunspots this magnetism has a strength of 2,500 to 3,500 gauss
(Earth’s magnetic field is less than 1 gauss at the surface); the field must
reach at least 1,500 gauss to form a dark spot.

Using more than 13 years of sunspot data collected at the McMath-Pierce
Telescope at Kitt Peak in Arizona, Penn and Livingston observed that the
average field strength declined about 50 gauss per year during Cycle 23 and
now in Cycle 24. They also observed that spot temperatures have risen
exactly as expected for such changes in the magnetic field. If the trend
continues, the field strength will drop below the 1,500 gauss threshold and
spots will largely disappear as the magnetic field is no longer strong
enough to overcome convective forces on the solar surface.

Moving outward, Richard Altrock, manager of the Air Force’s coronal research
program at NSO’s Sunspot, NM, facilities has observed a slowing of the “rush
to the poles,” the rapid poleward march of magnetic activity observed in the
Sun’s faint corona. Altrock used four decades of observations with NSO’s
40-cm (16-inch) coronagraphic telescope at Sunspot.

“A key thing to understand is that those wonderful, delicate coronal
features are actually powerful, robust magnetic structures rooted in the
interior of the Sun,” Altrock explained. “Changes we see in the corona
reflect changes deep inside the Sun.”

Altrock used a photometer to map iron heated to 2 million degrees C (3.6
million F). Stripped of half of its electrons, it is easily concentrated by
magnetism rising from the Sun. In a well-known pattern, new solar activity
emerges first at about 70 degrees latitude at the start of a cycle, then
towards the equator as the cycle ages. At the same time, the new magnetic
fields push remnants of the older cycle as far as 85 degrees poleward.

“In cycles 21 through 23, solar maximum occurred when this rush appeared at
an average latitude of 76 degrees,” Altrock said. “Cycle 24 started out late
and slow and may not be strong enough to create a rush to the poles,
indicating we’ll see a very weak solar maximum in 2013, if at all. If the
rush to the poles fails to complete, this creates a tremendous dilemma for
the theorists, as it would mean that Cycle 23’s magnetic field will not
completely disappear from the polar regions (the rush to the poles
accomplishes this feat). No one knows what the Sun will do in that case.”

All three of these lines of research to point to the familiar sunspot cycle
shutting down for a while.

“If we are right,” Hill concluded, “this could be the last solar maximum
we’ll see for a few decades. That would affect everything from space
exploration to Earth’s climate.”

                          # # #

Media teleconference information: This release is the subject of a media
teleconference at the current meeting of the American Astronomical Society’s
Solar Physics Division (AAS/SPD). The telecon will be held at 11 a.m. MDT
(17:00 UTC) on Tuesday, 14 June. Bona fide journalists are invited to attend
the teleconference and should send an e-mail to the AAS/SPD press officer,
Craig DeForest, at deforest@boulder.swri.edu, with the subject heading “SPD:
SOLAR MEDIA TELECON”, before 16:00 UTC. You will receive dial-in information
before the telecon.

These results have been presented at the current meeting of the AAS/SPD.
Citations:

16.10: “Large-Scale Zonal Flows During the Solar Minimum -- Where Is Cycle
25?” by Frank Hill, R. Howe, R. Komm, J. Christensen-Dalsgaard, T.P. Larson,
J. Schou & M. J. Thompson.

17.21: “A Decade of Diminishing Sunspot Vigor” by W. C. Livingston, M. Penn
& L. Svalgard.

18.04: “Whither Goes Cycle 24? A View from the Fe XIV Corona” by R. C.
Altrock.

 

 

  • Like 1

Share this post


Link to post
Share on other sites

To add to the helioseismology mysteries, here is another more recent release from Frank Hill at the NSO (this time in a blog post rather than in a press release): 

Do we see a dawn of solar cycle 25?

10178929_sc25helioseismology.thumb.jpg.fddce0ae1a328a29d02a11bf83b10f92.jpg

 

Does anyone see some 'contradiction' (if not confusion) in what the authors are implying in this NSO article.  They are suggesting the chart indicates that Oct 2019 for SC25 is temporally equivalent to Jan 2009 for SC24, and Jun 1997 for SC23.  Keep in mind that a large photospheric magnetic structure producing sunspots appeared above 40deg latitude in Nov 2008*; whereas, we have not yet seen for SC25 a significant photospheric magnet structure above 32deg latitude (producing sunspots or not).  Does it make one wonder whether an unspoken take-away from this article is that we indeed may continue to see SC25 dipolar magnetic structures, although they may not necessarily produce much sunspot activity beyond 'pores'?🤔😲

The article ends with the statement, "and now, it seems, we see the first sunspots of this cycle", but never mind that the first SC25 spots were seen a long time ago (was it in 2016?).

*(More on this is found in the threads titled,  "Synoptic Magnetograms; SC24 Minimum Forecasting" and "Solar Cycle 25 Forecasting".)

Edited by theartist
  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you also agree to our Terms of Use and our Privacy Policy.