Solar Cycle 24 Main Discussion X

[af4ex]

arjan
> 11158 is going nuts!
> Allthough it didn't flare yet, background xrays are steadily climbing
> over the last 12 hours and are hovering around C1 level for a few
> hours now.

Welcome to Solar Cycle 24!

Here's what 11158 looked like last night at Nobeyama (2250Z-0620Z), the lower-left spot in the 'gang of four'. Also, 1159 (upper-left) sparkles with flares.
solar.nro.nao.ac.jp/norh/html/10mins/2011/02/13/movie.html


The x-ray background is now at C1 level continuously, so these spots are probably even more active now!

[bradk]

af4ex-

Looks like you are getting your pop now! Lots of spots, but little area to speak of. They also seem t be moving equatorially.

[bradk]

Feb 10, 2011 16:47:55 GMT lsvalgaard said:

Feb 10, 2011 15:10:43 GMT bradk said:

Exactly, sunspot area is the proxy I have chosen to investigate...

Because the L&P effect firstly removes the smallest spots, its effect on the sunspot area is expected to be smaller, but still to be there.
One problem is that the relationship between spot count and area is not linear, so simply taking ratios will not work. It is possible to get a linear relationship by raising the sunspot area to a power of 0.732:



I show the data [monthly means] from 1946 [there is a reason for this that has nothing to do with L&P] until 1996 [just before the start of L&P]. So this relationship shows the 'normal' behavior.

Using this relationship we can calculate what sunspot number to expect for a given area if there were no L&P effect. Here is the result:



The observed values of SSN [red curve] do begin to fall below the calculated values showing that there is an L&P effect even when comparing to sunspot areas. Of course, eventually the sunspot area will also decline, but slower than the SSN, so there will be a difference due to L&P. If SSN and Area declined at the same rate, we would not see any difference.

It is possible that some part of the difference between the observed and calculated SSN is due to undercounting of sunspots by SIDC. What seems clear is that SIDC is not inflating the SSN.

Thanks Dr. Svalgaard-

Another showing through a proxy of how unknown an period we are entering witht he L & P effect.

Also, sorry for the delay, I have been actually working at work, I hate it when they make do that.

[bradk]

Feb 11, 2011 3:11:33 GMT lsvalgaard said:

Feb 11, 2011 3:08:04 GMT af4ex said:

It stopped rainging in Nobeyama long enough for me to grab a few microwave images to try to figure out what's going on with the high flux reports.

I think I see what's going on.

1). 1153 is still influencing the SFI. In the image below you can still see the microwave (17Ghz) glow from 1153, even though it's rotated to the far side. Microwaves are generated from magnetic action high in the corona. The 2.8Ghz stuff probably even higher than the 17Ghz.

2). There are more magnetically active regions than officially reported. NOAA/USAF currently only lists 1156 and 1157, but there are at least four more than are radiated microwaves and have distinct 'beta' patterns in the magnetograms. These regions produce microwaves, which you can see in the Nobeyama image.

So I think this activity is at least partially responsible for keeping the SFI around 90.

Some of these may get recognized officially, but only if they develop visible spots.

Perhaps a taste of the future, if the L&P effect becomes reality, the SN will be hovering around zero while the SFI goes into the 90's, like today. (The Sun looks almost spotless, except for 1156.)

NOAA only numbers a region if there is a spot in it which has been seen by more than one observer, lived for more than 12 hours [and a few other criteria]. We might see this happen more and more often, and NOAA might rethink what to number...

For consistency, I hope any change reflects these in the active region number, but please do not call them sunspots.

[N9AAT]

Bob and Doc I (or anyone else of course),

I know things are going to get exciting today but I have a question sorta in a different direction. You may have noticed from previous posts (kinda infrequent, I know) that I'm a NAVAID tech. I had a most interesting event occur last Friday and wonder what you think about it.

One of my VOR sites was being orbited by Flight Check just about the time that the Geo storm started on Friday. F/C took me off the air, that is they NOTAM'ed my VOR out of service because all of the radials were 3 degrees off. You don't want airplanes using your site when it's that far off.

Normally, internal monitoring by the VOR itself will shut the facility down when it goes 1 deg off on ANY radial. 16 small antennas around the site's counterpoise constantly monitor the signnal. The site itself saw no problems, did NOT shut down, and when we checked it, everything was fine. Apparently the radial "bending" was only in space, not at the site.

Three days later a F/C aircraft flew another orbit and all the radials were ... perfect.

What could the geo storm have done to us?

I had a similar event happen about 8 months ago at another site, in Southern Indiana, where only the radials east and south of the site "changed" by up to 5 degrees, then went back to normal a few days later. This time is was several commercial aircraft who reported the radial angles off, compared to GPS, and by the time Flight Check got there everything was back to normal.

At issue is whether we ought to be taking sites off the air during a Geo storm. There's a lot of expense involved in having special aircraft come down to put us back on the air, plus the time that a NAVAID is down and unavailable.

Some of us are already pushing these questions "upstream" but I was wondering what you guys think, since I HIGHLY value your knowledge of solar and geo mag things.

Thanks.

[af4ex]

bradk
> For consistency, I hope any change reflects these in the
> active region number, but please do not call them sunspots.

But one could argue that, due to the L&P discounting, invisible spots may have to be included as 'active regions' to maintain a uniform representation of activity.

You can see it already, a lot of activity is going on in the invisible and nearly-invisible spots. This will get worse as L&P progresses.

But I can also see that one could also argue 'sunspots for sunspots sake', and continue only registering the regions bearing visible sunspots.

[bradk]

af4ex-

True, but if we call them spots now we would not being true to the sunspot record, as previously they were not called spots (e.g. during prior minima). I agree we should call them something, but active regions seems to be the term of choice out there to cover this...

[N9AAT]

Oh, and one other thing in case you're wondering. Yes, VOR sites have been around for a long time. I think the reason we may be seeing this effect now rather than years ago is the prolific use of GPS. VOR radials are referenced to magnetic north while GPS is references to geographic north. A GPS must have a declination map loaded so it knows the difference between the two, but of course that correlation map is static.

I know that in the case of the commercial aircraft who turned in reports that took me off the air 8 months ago. They were calling out the DIFFERENCE between GPS headings and VOR headings. The Center in Indianapolis didn't know WHAT to do, so they took me off the air because there were so many reports.

Again, when Flight Check arrived later from Battle Creek, MI, everything was normal.

I wish I'd have had a compass set up when this latest geo storm started. I wonder if you could actually see it? I understand the K-Index went to 5 and at least one station reported a 6.

[bradk]

Feb 13, 2011 3:12:53 GMT lsvalgaard said:

X-posted from WUWT:
The polar fields have been changing of late. There are several points to make here:
5) the past few months have seen a very powerful surge of positive polarity towards the north pole [but none so far towards the south]. Because the polar fields were already weak, this surge has completely cancelled the north polar fields, even to the point that the polar coronal hole that normally lives there has virtually disappeared. You can see that here: stereo-ssc.nascom.nasa.gov/beacon/beacon_secchi.shtml
6) since we expect more surges in the year(s) to come it thus seems possible that the north polar fields might build to be stronger than they have been at this last minimum, thus presaging a large cycle 25. We don’t know this for sure, of course, but it seems very possible to me. This is somewhat unexpected, so, yes, these are interesting times

To these last two points, could solar cycle 25 be large based on this, but have few if any sunspots if the L & P effect continues? That could be the strangest of all outcomes...

[af4ex]

bradk
> Looks like you are getting your pop now! Lots of spots ...

Yes, and if Cycle 14 (1902-1913) can be used as a prototype, this spike may continue for 2-3 months until it peaks, then a reverse spike back into the doldrums. Many up-and-down spikes like this characterized Cycle 14.

[bradk]

Feb 13, 2011 13:57:40 GMT N9AAT said:

Oh, and one other thing in case you're wondering. Yes, VOR sites have been around for a long time. I think the reason we may be seeing this effect now rather than years ago is the prolific use of GPS. VOR radials are referenced to magnetic north while GPS is references to geographic north. A GPS must have a declination map loaded so it knows the difference between the two, but of course that correlation map is static.

I know that in the case of the commercial aircraft who turned in reports that took me off the air 8 months ago. They were calling out the DIFFERENCE between GPS headings and VOR headings. The Center in Indianapolis didn't know WHAT to do, so they took me off the air because there were so many reports.

Again, when Flight Check arrived later from Battle Creek, MI, everything was normal.

I wish I'd have had a compass set up when this latest geo storm started. I wonder if you could actually see it? I understand the K-Index went to 5 and at least one station reported a 6.

This is an incredibly interesting finding. Do you have a link where they describe exactly how VOR works to determine relative position? Are they just using magnetism? If so, you might be seeing a small relative change in the local magentism because of geo magnetic effects caused by the storm, but someone more knowledgeable than I will have to tell you if that has been seen before or is plausible.

[bradk]

af4ex-

Yes, it seems the folks betting on 14, including you, may turn out to be correct. Time will tell if the divergence in SSN area/SSN number leads to fewer spots faster, and thus only the flux follows 14 - as it does not look like an L & P effect was occurring in 14.

[N9AAT]

You can Google for several good articles, including a couple of nice videos. The site is usually a 100-watt transmitter using an Alford-Loop antenna, radiating in all directions in the 108-118 MHz band, just above FM. A goniometer produces modulation that the aircraft decodes to get azimuth to or from the site. Basically, it's a direction finder in reverse. Most sites also have a separate DME transmitter in the UHF range that gives distance from the site. So with angle and distance you have a complete navigation aid.

All of this is, of course, what will be replaced entirely someday by GPS.

I've been doing this kind of work 30 years now, and have never seen this effect before. Of course previously we didn't have GPS to compare with live in real time. A pilot may never have noticed anything out of the ordinary since apparently the effect is only temporary.

By the way, I am NOT an engineer. I'm only a "ground pounder" who does the PM's and tweaks the sites from time to time.

[af4ex]

> Yes, it seems the folks betting on 14, including you, may
> turn out to be correct.

These observations of the current solar situation are entirely consistent with Dr. Svalgaard's assertion that the Sun is in the same state as it was in 1903.

[N9AAT]

Off to church. Back on later. Wonder what will happen today. ;D