Solar and Aurora Activity Chat

[mettalfabrik]

another snippet that may help the laymen amongst us concerning spotless days over the last century

from the australian space weather agency concerning the last minima with a nod to the current minima

The Sun and Solar Activity

Sequences of Spotless Days on the Sun

During September and October of 1996, we experienced a sequence of 37 days in a row during which there were no spots observed on the sun. This sequence is longer than any during recent solar minima - consistent which the current minimum being "deeper" than those during recent solar cycles.

But how does this sequence compare with historical sequences from the record of sunspot observations. The following table makes this comparison for observations since 1900 table.

Year of Sequence Number of Spotless Days

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

1913 92

1901 69

1902 49

1902 45

1912 43

1901-2 40

1924 39

1913 39

1996 37

1933 36

1944 36

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

The table shows that the 1996 sequence, whilst impressive, is still considerably shorter than some early in the century. However, a note of caution is required because the coverage of observations was not nearly as good early this century as it is now. A sequence of spotless days can be broken by a single day on which a small spot appears. Lack of coverage by observations could therefore be very important in determining the length of such spotless sequences.

With the above qualification, the sequence in 1996 is still the longest observed in the last 50 years during which good observations have been available.

Material Prepared by Richard Thompson. © Copyright IPS - Radio and Space Services.

http://www.ips.gov.au/Educational/2/2/7

Edited October 1, 2008 by blackdown

[Roger J Smith]

Let's put this in some context. If there is indeed any correlation between weather and solar activity, then we should have a good overview of what happened in past episodes of low solar activity.

Forget the Maunder minimum for the time being, that was essentially a period of 60 years with almost no activity (just a few tiny peaks). Since then, and also largely before then according to Schove's extensive research, the Sun has two basic modalities, active with regular, frequent 10-year cycles, and weak with irregular 12-15 year cycles.

There is no known precise rhythm to these, and no theory to explain why the Maunder minimum came and went, or the almost as quiet Sporer minimum two centuries earlier.

But the statistics show that these longer active periods are usually 80-120 years long while the shorter inactive spells are 30-50 years long.

The last two significant inactive spells both produced three peaks and had a similar duration if measured from the peak of the last active cycle to the peak of the first active cycle in the next active period. These would be (1787 to 1837) 50 years and (1870 to 1917) 47 years. The three weaker cycles in these periods (the Dalton and I'm not sure what if anything they call the next one) came at this interval (14, 29, 43 years) and (13, 23 and 35 years). The Dalton minimum was probably a bit more pronounced than the more recent one 1875-1915 or so.

Both featured two or three year periods without much activity between the various peaks, the longest being about four years 1808-11 inclusive. However, in both of these quieter Sun episodes, some of the coldest UK winters came during the gradually rising sunspot counts towards moderate or weak peaks. Examples would include 1814, 1830, 1879-81, 1891.

So if we start seeing a few sunspots and small counts like 10 or 20 through the next few months and next year, this will not be a bad thing if you're hoping for some colder weather.

On the other hand, some of the coldest winters have come near very active peaks -- 1838, 1947, 1979 are examples.

To be frank, without the Maunder minimum, there might not be a very strong case for solar activity connections to weather variations. I'm not saying it is unproven, but the correlation is at a rather low level and there is very little progress on getting a more detailed understanding of what the process is. A Maunder type minimum might be a special case that is easier to accept.

[BLAST FROM THE PAST]

To be frank, without the Maunder minimum, there might not be a very strong case for solar activity connections to weather variations. I'm not saying it is unproven, but the correlation is at a rather low level and there is very little progress on getting a more detailed understanding of what the process is. A Maunder type minimum might be a special case that is easier to accept.

Roger

Indeed as your research shows there is very likely to be more than one ingredient in the pot.

BFTP

[Guest Shetland Coastie]

Sorry SC this is a thread about solar activity - not yet another thread for a dozen or so people to hijack and go on and on about their denial theories about global warming. My post was in that context - please stick to that topic.

Er, no Shuggee, you were the one who suggested there was no link between solar activity and climate. I disagree. Over the last few decades whilst we have seen warming, is it purely coincidental then that solar activity was at a peak? Is it also a coincidence that now we have a very quiet sun, global temperatures have now fallen? I certainly don't think so.

Oh look, no sunspots:

Spaceweather

Edited October 2, 2008 by Shetland Coastie

[laserguy]

Sorry SC this is a thread about solar activity - not yet another thread for a dozen or so people to hijack and go on and on about their denial theories about global warming. My post was in that context - please stick to that topic.

True,true,but..... solar activity/climate 'change' are inseperable. Global warming's (say what?) pernicious reach is now so widespread that it's impossible to talk about weather/climate/last night's telly/next door's new curtains, without it peeping over your shoulder. Further,I don't hear you or any of the 'warmers' (sorry) object when failure of cold/snow is described as the 'even larger teapot' and all that implies,or being in the era of global warming.

The insistence of the likes of the BBC,the government,Greenpeace,Hansen etc etc of perpetuating the outright falsehood that warming is ongoing,reminds me of the hoary old bikers on Triumph Bonnevilles and BSA's going down' the Ace Cafe,wearing pudding basin helmets and goggles and white socks peeping over the top of boots;stuck in some sort of time-warp unaware that things have moved on. Warming stopped,ceased,finished years and years ago. It is now cooling,and far,far more profoundly than warming ever manifested itself. I don't want to know about 'trends',this is the here and now,this is the state of play. If and when warming resumes (and you know it'll only need do so for an instant to get the whistles and bells going at full tilt, instead of the desperati now being reduced to such utter drivel as claiming polar bears are at risk of hearing damage due to being within earshot of cracking ice and calving glaciers),we'll talk about it then,and what ol' sol happens to be up to at the time. Me,I'm at risk of sanity loss due to the AGW garbage I'm barraged with on a daily basis. Anyways,where were we? Ah yes,the sun,and the concurrent narcolepsy of said body and plunging world temps. A link? Nah,can't see it myself.

I've a feeling this post will be removed,in which case would be very telling...

[shuggee]

Any sunspots yet?

(And yes - any further nonesense about AGW will be removed)

[laserguy]

Any sunspots yet?

(And yes - any further nonesense about AGW will be removed)

I'll try again - no, 'fraid not.

[Paul]

Look folks, I think it's pretty simple. This thread was created to be a discussion solely around sunspots, not climate, warming, cooling or anything else. If anyone wishes to discuss the link between climate and sunspots, then please use the appropriate part of the forum, which is of course the climate area.

Yes, many topics are linked, but they can also be treated as separate entities too, and there is opportunity to discuss all aspects of weather, climate, space, science and so on, but within the relevant threads and parts of the forum. So please, leave this as a simple sunspot discussion thread and take the climate discussion to the climate area on here..

[Mondy]

Out of interest, solar wind is currently more than 600km/s. Bz component is at 0. If it drops suddenly to minus figures and the K -index rises to above 6, aurora might be visible in the far north, but a long shot...still...a heads up if you like!

[Crepuscular Ray]

Interesting stuff from NASA about the macro changes in the Sun during the sunspot cycle.

[Mondy]

Anyway, solar wind currently well over 600km/s, K index at 4. This equates to no visible aurora over the UK, even Shetland..pfftt!

Edited October 2, 2008 by Paul
Wonder why this was edited?!

[jethro]

Lots of information here on how this cycle is progressing in comparison to past cycles:

http://users.telenet.be/j.janssens/SC23web/SCweb8.pdf

[Guest Shetland Coastie]

Anyway, solar wind currently well over 600km/s, K index at 4. This equates to no visible aurora over the UK, even Shetland..pfftt!

Its been that dreich over the last few days I wouldn't have seen it anyway

Lots of information here on how this cycle is progressing in comparison to past cycles:

http://users.telenet.be/j.janssens/SC23web/SCweb8.pdf

Yes interesting stuff that Jethro

[Crepuscular Ray]

They seem to be a bit more positive about it now. Given its latitude, it's more likely to be cycle 24, but it's still almost invisible at visible wavelengths and a bit wimpy on Soho's magnetogram images. Ho hum.

[laserguy]

They seem to be a bit more positive about it now. Given its latitude, it's more likely to be cycle 24, but it's still almost invisible at visible wavelengths and a bit wimpy on Soho's magnetogram images. Ho hum.

All the cycle 24 spots have been wimpy so far,as if they appear reluctantly then decide almost straight away that they've had enough already and then disappear whence they came! Are the first spots of all new cycles as shy as this,or is this unusual behaviour too?

[BLAST FROM THE PAST]

Fear not it has to start sometime. The essential part is that 24 is already late, very late and the behaviour is of Dalton proportions. This is interesting but 25 will be the baby

BFTP

[LadyPakal]

Looks like the proto-spot has faded out now.

[Mondy]

With September passed, we now can calculate the 3-month average of sunspot numbers centered on August, which was 1.1. Compare that with 3 month averages going back to June 2006.

Jun 06 28.9

Jul 06 23.3

Aug 06 23.5

Sep 06 21.2

Oct 06 24.1

Nov 06 23.1

Dec 06 27.3

Jan 07 22.7

Feb 07 18.5

Mar 07 11.2

Apr 07 12.2

May 07 15.8

Jun 07 18.7

Jul 07 15.4

Aug 07 10.2

Sep 07 5.4

Oct 07 3

Nov 07 6.9

Dec 07 8.1

Jan 08 8.5

Feb 08 8.4

Mar 08 8.4

Apr 08 8.9

May 08 5

Jun 08 3.7

Jul 08 2

Aug 08 1.1

http://www.southgatearc.org/propagation/2008/october_04.htm

[Guest Shetland Coastie]

Looks like the proto-spot has faded out now.

Indeed. Sun is blank again.

Spaceweather

[Anti-Mild]

Fear not it has to start sometime. The essential part is that 24 is already late, very late and the behaviour is of Dalton proportions. This is interesting but 25 will be the baby

BFTP

Now I'm not suggesting for a moment that what I am going to propose will happen, but as a layperson in terms of solar cycles, etc., I have to wonder, if it was possible to go back to the time prior to the LIA and observe the sunspot record, what would it look like?

Who's to say that rather than moving towards a Dalton style minimum that it wont be a more extreme Maunder style minimum After all, it's my perception that science's understanding of what the sun does and why it does it is still in it's relative infancy.

My opinion is, if we are heading towards a Dalton style minimum, that the climate will cool, although it will be offset somewhat by AGW, perhaps resulting in a localised climate similar to that experienced in the 1980's by the year 2025ish. However, should the minimum be Maunderesque, then there could be enough of a cooling effect to ultimately bring about conditions similar to those in the late 1800's.

It's all conjecture and supposition really.

[michail]

Indeed. Sun is blank again.

Spaceweather

Or, maybe not....

http://www.solarcycle24.com/index2.htm

[Gray-Wolf]

Thanks for that Michail!

Here we are talking about the long min. and the sun sems to be starting up again (over the past 2 weeks compared to the last few months).

I asked before but didn't (to my knowledge) get a reply so here goes again. Will the start of the new cycle proper (predominance of C24 spots) be a slow growth in numbers or do the numbers tend to jump up quite quickly?

Edited October 4, 2008 by Gray-Wolf

[LadyPakal]

Thing is about a lot of these really small spots & proto-spots. We've only been able to see them faily recently using the new imaging tools. Back just a few decades these would never have been visible - how do we tell what the spot counts really would have been 50, 100 years ago if current technology had been available.

I think the only true way to reconcile this is to only use the tools available back then, to create a spot count which is on a level playing field with those from earlier times.

[michail]

I don't know much about sunspots, but the last few small ones that have appeared are from SC24. They seem to be getting more frequent but are not lasting long.I'm just keeping my eye on them to see if they start lasting longer, then l'll know that SC24 has started for certain!

[mettalfabrik]

Thing is about a lot of these really small spots & proto-spots. We've only been able to see them faily recently using the new imaging tools. Back just a few decades these would never have been visible - how do we tell what the spot counts really would have been 50, 100 years ago if current technology had been available.

I think the only true way to reconcile this is to only use the tools available back then, to create a spot count which is on a level playing field with those from earlier times.

well ladypakal this is what they try to do,as there are various sunspot numbers counts,the older visual methods are still used to provide a continum from past centuries so that this data sits alongsode the more modern methods

http://sidc.oma.be/news/106/welcome.html