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Post by Bob k6tr on Feb 9, 2011 23:33:32 GMT
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bradk
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Posts: 199
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Post by bradk on Feb 10, 2011 0:35:17 GMT
First!
I still would love to see a running area/sunspot for a bunch of cycles. Is this data anywhere?
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Post by lsvalgaard on Feb 10, 2011 0:54:17 GMT
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bradk
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Posts: 199
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Post by bradk on Feb 10, 2011 12:03:55 GMT
Thanks Dr. Svalgaard- I know of that data and linked to it a few days back, but what I really want is sunspot area/sun spot number giving an area per spot, or a poor man's secondary proxy for the L & P effect. I could just do the division and hope the data actually is robust and directly comparable on a day to day basis all the back through the record, but you have already stated it is not so a person more aware of the possible issues with the dataset ought to do it. I expect it is out there, if I had time to find it. That said I have found lots of old school cool on suspot areas, such as this showing a periodicity in the areas: articles.adsabs.harvard.edu//full/1990A%26A...238..377C/0000377.000.html And here is an article John might be interested in as he has noted rotation in groups: adsabs.harvard.edu/full/1986A%26A...155...87BThis article might have the data I want, but I am too cheap to pay for it: www.springerlink.com/content/p041n1564611q633/ |
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bradk
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Posts: 199
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Post by bradk on Feb 10, 2011 12:37:53 GMT
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Post by af4ex on Feb 10, 2011 13:02:21 GMT
Remember AR11149? It rotated farside on 28-Jan with a departure fireworks display not unlike 1153's: an M-class and two C-class flares: #Event Begin Max End Obs Q Type Loc/Frq Particulars Reg#
#-------------------------------------------------------------------------------
5110 + 0044 0103 0110 G15 5 XRA 1-8A M1.3 9.5E-03 1149
5140 + 0402 0425 0435 G15 5 XRA 1-8A C1.5 1.6E-03 1149
5150 + 1005 1022 1030 G15 5 XRA 1-8A C1.5 1.4E-03 1149
STEREO and Raben both show 1147/1149 still active and ready to rotate back into view. But I'm not seeing much of an x-ray/EUV "pre-glow" on the east limb, so I'll keep my expectations low on this one (and hope it surprises us) :-| Attachments:
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Post by af4ex on Feb 10, 2011 14:44:31 GMT
bradk> Here is a tantalizing taste of what I want (see page 9) wherein > the the L & P effect could be effecting the area/group in cycles > 21 and 22 and thus what they were seeing was real but they > had no explanation for it. If this is correct it could also move > the L & P effect beginning back to an earlier date, maybe: Wilson and Hathaway are comparing spot area (total or per spot?) to the number of groups. But both of these tend to vanish as B -> 1500 Gauss. Wouldn't it be better to characterize this process using "non-vanishing" attributes, such as magnetic field vs. temperature, or something similar (e.g. spectral line intensities)?
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bradk
Level 3 Rank
Posts: 199
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Post by bradk on Feb 10, 2011 14:59:31 GMT
John-
Of course the best thing to use is magnetism on a per spot basis, but we just don't have that data going back very far (if I understand the datasets), thus the question becomes what data do we have and how far back does it go, and could that data be relevant to address any questions surrounding whether an L & P effect existed in any prior cycle. I think the only data we have a great history on is sunspot area, namely that sunspots will get smaller before they disappear as magnetism drops, thus indicating an L & P or at least a magentic change. Thus my questions - have spots gotten smaller or had different areas per spot or group in other cycle which might indicate a magnetic change or an L & P effect.
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Post by af4ex on Feb 10, 2011 15:02:49 GMT
bradk> ... but we just don't have that data going back very far ... Find a proxy. [Easier said than done  ]
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bradk
Level 3 Rank
Posts: 199
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Post by bradk on Feb 10, 2011 15:10:43 GMT
Exactly, sunspot area is the proxy I have chosen to investigate...
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Post by lsvalgaard on Feb 10, 2011 16:47:55 GMT
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. |
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Post by af4ex on Feb 10, 2011 21:32:23 GMT
Surprisingly, the SFI has gone back up to 91. And I don't think 1153 can take credit for it any more. Maybe the microwave background component of the SFI is picking up somehow.
Penticton 1700Z, 2000Z, 2300Z:
2011 Feb 2 2800 79 79 79
2011 Feb 3 2800 80 80 80
2011 Feb 4 2800 81 82 81
2011 Feb 5 2800 81 81 80
2011 Feb 6 2800 80 80 80
2011 Feb 7 2800 82 82 82
2011 Feb 8 2800 91 90 91
2011 Feb 9 2800 90 89 88
2011 Feb 10 2800 91 91 --
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Post by af4ex on Feb 10, 2011 21:49:47 GMT
... or could SFI rise be due to AR1156. which is displaying two 'super-strength' UV-sunspots in 1700A light? It has overtaken AR1157 in activity (which has only one such spot, fainter). Attachments:
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Post by af4ex on Feb 11, 2011 0:33:48 GMT
The 2300Z reading from Penticton dropped slightly to 90. Penticton 1700Z, 2000Z, 2300Z: 2011 Feb 7 2800 82 82 82 2011 Feb 8 2800 91 90 91 2011 Feb 9 2800 90 89 88 2011 Feb 10 2800 91 91 90 I was hoping the microwave radioheliograph at Nobeyama would provide some clues to the source of this high flux. But they've been enduring freezing rain today (and snow forecast tomorrow), which greatly interferes with the 17Ghz imaging, as you can see below. www.accuweather.com/en-us/jp/nagano/nobeyama/hourly.aspxAttachments:
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Post by af4ex on Feb 11, 2011 1:11:31 GMT
Summarizing the recent events: the trend has reversed and is now up! Attachments:
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