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.
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:
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)?
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.
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.
Last Edit: Feb 10, 2011 17:11:08 GMT by lsvalgaard
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 --
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.