|
|
Post by janjanssens on May 5, 2012 11:54:40 GMT
Hi there Where can I see the latest trend in sunspots such as on Solarham.com? If I plot myself with the given monthly values, we have reached the cycle 24 peak already then? Is this correct and the trend moving downwards? You may want to consult my webpage "Evolution of SC24" at users.telenet.be/j.janssens/SC24web/SC24.htmlBesides sunspot numbers, it tracks also solar flares, geomagnetics, radio flux, cosmic rays,... An overview of SC24-predictions (made prior to 2009 = prior to SC-minimum) can be found at users.telenet.be/j.janssens/SC24.html At this time (only 40 months after cycle minimum), we have not reached SC24-maximum yet. This is expected to occur in the first half of 2013. Currently, we seem to be in a standstill very similar to what happened during SC23 (albeit this time later in the cycle and at a lower sunspot level: see users.telenet.be/j.janssens/SC24web/SC24.html#RSC24 ). |
|
|
|
Post by lsvalgaard on May 5, 2012 13:11:20 GMT
Hi there Where can I see the latest trend in sunspots such as on Solarham.com? If I plot myself with the given monthly values, we have reached the cycle 24 peak already then? Is this correct and the trend moving downwards? You may want to consult my webpage "Evolution of SC24" at users.telenet.be/j.janssens/SC24web/SC24.htmlBesides sunspot numbers, it tracks also solar flares, geomagnetics, radio flux, cosmic rays,... An overview of SC24-predictions (made prior to 2009 = prior to SC-minimum) can be found at users.telenet.be/j.janssens/SC24.html At this time (only 40 months after cycle minimum), we have not reached SC24-maximum yet. This is expected to occur in the first half of 2013. Currently, we seem to be in a standstill very similar to what happened during SC23 (albeit this time later in the cycle and at a lower sunspot level: see users.telenet.be/j.janssens/SC24web/SC24.html#RSC24 ). Your TSI plot [based on PMOD it seems] shows a minimum value 0.2 W/m2 below the previous minimum values. Recent calibrations show that that value is in error. The is no difference between minima, see: slides 31-33 of lasp.colorado.edu/sorce/news/2011ScienceMeeting/docs/presentations/1g_Schmutz_SORCE_13.9.11.pdf |
|
|
|
Post by justsomeguy on May 5, 2012 13:23:12 GMT
Hi there Where can I see the latest trend in sunspots such as on Solarham.com? If I plot myself with the given monthly values, we have reached the cycle 24 peak already then? Is this correct and the trend moving downwards? Trend charts are in the drop down on the upper left of the homepage: www.solarham.com/trends.htmHere is NASA's latest prediction: solarscience.msfc.nasa.gov/predict.shtmlDr. Svalgaard, do you agree with the prediction? |
|
|
|
Post by lsvalgaard on May 5, 2012 15:57:51 GMT
Hi there Where can I see the latest trend in sunspots such as on Solarham.com? If I plot myself with the given monthly values, we have reached the cycle 24 peak already then? Is this correct and the trend moving downwards? Trend charts are in the drop down on the upper left of the homepage: www.solarham.com/trends.htmHere is NASA's latest prediction: solarscience.msfc.nasa.gov/predict.shtmlDr. Svalgaard, do you agree with the prediction? Hathaway's chart is not really a prediction, but a fit to how the cycle has progressed so far. [more correctly the relative proportion of the original prediction and observations changes as the cycle progresses. Now the observations are having the greater weight]. And one cannot disagree with the observations. The question is: How well do the observations up to now determine the rest of the cycle? and that is where the opinions can differ. I predict  that Hathaway's predictions will fluctuate up and down during the rest of the cycle. |
|
|
|
Post by janjanssens on May 6, 2012 8:20:48 GMT
Leif, Thanks for the info. I added a caution note and the link to the SORCE presentation. As soon as pmod/wrc changes the final data, it will be reflected in the graph. Reading the conclusion (slide 33), Mr. Schmutz seems to indicate the problem is rather with the SC23 data (1996). So, OK for no clear trend between SC23-SC24 minima, but still a downward trend compared to previous SC21-SC22 minima? The reduction from raw to final TSI data remains a cumbersome and slippery burden. Reading (slide 32) that 2 cavities may not be enough to correct for the in-flight degradation is only adding to the uncertainty. |
|
andor
Level 2 Rank
Posts: 60
|
Post by andor on May 9, 2012 12:42:04 GMT
Because SC23 minimum came down approx 2 years late, can SC24 be peaking 2 years earlier than the predicted trend?
|
|
|
|
Post by janjanssens on May 10, 2012 17:29:17 GMT
Because SC23 minimum came down approx 2 years late, can SC24 be peaking 2 years earlier than the predicted trend? There's a nice animation at wattsupwiththat.com/2011/01/18/nasa-sunspot-number-predictions-revised-again/, showing how the NASA/MSFC predicted timing of SC-maximum got delayed as their predicted maximum decreased: From 2010-2011 with SSN=160 (prediction 2006-2007) to late 2012 with SSN=100 (prediction early 2009). Since then, timing has changed relatively little (+ 6 months) compared to their currently predicted SSN (down to 60). |
|
|
|
Post by semimadscientist on May 11, 2012 11:45:03 GMT
This cycle so far is further proof that every cycle is different. However, it’s similarity to cycle 14, albeit somewhat scaled- down, was noteworthy earlier on in the cycle. This began to change, though, with indications of a sharp upswing in flux and sunspot number. This was picked- up on more than a year ago by Bob k6tr, but at the time I was still a fan of the cycle 14 model, and have been surprised by what’s happened over the past year or so.
What we have now is a very “spiky” cycle, like cycle 14 (and to a lesser extent, cycle 10), but more like cycle 10 in overall shape (the very low start but the sharp upswing), albeit very small in size.
Noting that cycles which rise sharply to maximum (as it is highly likely that cycle 24 is doing) tend to be asymmetrical (short rise but long fall), I’m figuring that this cycle may turn out to be at least 11 years long. However, it’s also noteworthy that low cycles tend to be symmetrical, and thus for this cycle, short. I’m wondering where would most of the experts lay their money on the shape of this cycle if they were pressed to do so?
Also, Dr Svalgaard, you once speculated that the weak flux of this cycle could portend a strong cycle 25 in terms of flux values, at least. I have one question on the relationship between flux and sunspot number though- in a situation where cycle 25 turns out to be a strong cycle in terms of flux, but the L&P effect continues, could there be more sunspots in association with higher flux, although the magnetic field strength of these spots still low and heading for the 1500 Gauss mark in time? Could it work that way?
Thanks.
|
|
|
|
Post by lsvalgaard on May 13, 2012 6:16:43 GMT
This cycle so far is further proof that every cycle is different. However, it’s similarity to cycle 14, albeit somewhat scaled- down, was noteworthy earlier on in the cycle. This began to change, though, with indications of a sharp upswing in flux and sunspot number. This was picked- up on more than a year ago by Bob k6tr, but at the time I was still a fan of the cycle 14 model, and have been surprised by what’s happened over the past year or so. What we have now is a very “spiky” cycle, like cycle 14 (and to a lesser extent, cycle 10), but more like cycle 10 in overall shape (the very low start but the sharp upswing), albeit very small in size. Noting that cycles which rise sharply to maximum (as it is highly likely that cycle 24 is doing) tend to be asymmetrical (short rise but long fall), I’m figuring that this cycle may turn out to be at least 11 years long. However, it’s also noteworthy that low cycles tend to be symmetrical, and thus for this cycle, short. I’m wondering where would most of the experts lay their money on the shape of this cycle if they were pressed to do so? Also, Dr Svalgaard, you once speculated that the weak flux of this cycle could portend a strong cycle 25 in terms of flux values, at least. I have one question on the relationship between flux and sunspot number though- in a situation where cycle 25 turns out to be a strong cycle in terms of flux, but the L&P effect continues, could there be more sunspots in association with higher flux, although the magnetic field strength of these spots still low and heading for the 1500 Gauss mark in time? Could it work that way? Thanks. The way the L&P works is that we will see fewer sunspots for a given flux, so that the cycle strength measured by sunspots will fall below that measured by flux. |
|
|
|
Post by semimadscientist on May 13, 2012 14:17:24 GMT
The way the L&P works is that we will see fewer sunspots for a given flux, so that the cycle strength measured by sunspots will fall below that measured by flux. Good, thanks. Then once we have enough empirical data on sunspot field strength, we will be able to devise a formula which determines the expected sunspot number given a known flux value and a known sunspot magnetic field strength value. A further question, if I may: given a) that the length of a solar cycle is determined partly by the size of the cycles either side (and this is an assumption and perhaps misunderstanding on my part), and b) that you are right about cycle 25 being a strong cycle in terms of flux values, could it be said that cycle 24 is destined to be a short cycle? Also, it seems to me that in an interesting situation where you have a low- flux (i.e. a weak-) cycle followed by a high- flux cycle, and a superimposed L&P effect, the sunspot minimum and the flux (or true-) minimum might be out of sync, and I wonder if this could affect the apparent minimum between this cycle and the next, if solar flux gets back to normal or near- normal next cycle. |
|
|
|
Post by justsomeguy on May 15, 2012 6:17:20 GMT
|
|
|
|
Post by af4ex on Jun 5, 2012 23:24:02 GMT
|
|
|
|
Post by kb0kyv on Jun 16, 2012 3:25:16 GMT
I've noticed that the solar flux values given on the solar ham site are often different and usually higher than those given on the N0NBH site and on QRZ. What's going on here?
|
|
|
|
Post by justsomeguy on Jun 16, 2012 12:30:49 GMT
Since this site uses the N0NBH feed, it is impossible for them to be different. Try reloading, you may be looking at a cached page.
|
|
|
|
Post by lsvalgaard on Jun 16, 2012 14:26:43 GMT
Since this site uses the N0NBH feed, it is impossible for them to be different. Try reloading, you may be looking at a cached page. Also be aware of the difference between the flux as observed and as adjusted to 1 AU. |
|
that Hathaway's predictions will fluctuate up and down during the rest of the cycle.