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Post by lsvalgaard on Jun 12, 2009 18:30:01 GMT
Dr. Svalgaard, Thank you for publishing the daily graph of TSI, Flux, MF and SSN on your website. link for those who haven't seen it: www.leif.org/research/TSI-SORCE-2008-now.pngQuestion: what source is your standard for the SSN? I notice that your chart only shows 2 or 3 spotless days in June, whereas I believe that NOAA has called June 6,7,10 and 11 as spotless. Also, do you show one daily datapoint for each parameter, or more? Thanks The SSN is my own and is only preliminary. Once I get 'official' numbers I often change my assessment. Whether or not I put a spot on a day depends on NOAA, Brussels, US Air Force, MDI, Gong, Catania, etc. This is not archival-quality data, but is only a rough sketch. The chart is updated every time I have new data, sometimes several times a day, sometimes not for several days [if I'm on the road]. |
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Post by nobrainer on Jun 13, 2009 2:24:44 GMT
Leif, This paper by Tlatov and Markarov studies the variation in rotation periods of the solar surface. www.solarstation.ru/TL/PDF/tl_22.pdfIt seems that at Rmax of even solar cycles the low latitude photosphere speeds up and the mid-latitude photosphere slows down. In odd numbered cycles the low latitude again speeds up but to a lesser degree, and the mid-latitude also speeds up. What do you make of this? By the way, thanks for posting the Babcock 1961 paper on your website. edit: Had "odd" and "even" reversed. Fixed. Thanks for the paper...another one to file under "solar rotation" |
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Post by lsvalgaard on Jun 13, 2009 6:03:54 GMT
Leif, This paper by Tlatov and Markarov studies the variation in rotation periods of the solar surface. www.solarstation.ru/TL/PDF/tl_22.pdfIt seems that at Rmax of even solar cycles the low latitude photosphere speeds up and the mid-latitude photosphere slows down. In odd numbered cycles the low latitude again speeds up but to a lesser degree, and the mid-latitude also speeds up. What do you make of this? By the way, thanks for posting the Babcock 1961 paper on your website. edit: Had "odd" and "even" reversed. Fixed. Thanks for the paper...another one to file under "solar rotation" The paper by my good friend Andrei Tlatov and the late V. Makarov is too speculative for my taste. The paper relies on a technique introduced by the Stanford Group: Duvall T. L., Wilcox J. M., Svalgaard L., Scherrer P., & McIntosh P. S. 1977, Solar Phys.. There is not general acceptance of ANY of these long-term solar rotation rates [including our own data] as the noise simply is too great. The idea that a relic very strong magnetic field exists in the solar core has effectively been shot down by helioseismology as such a field would alter the sound speed in the solar interior and destroy the very good agreement between measured sound speed and the speed calculated from our theoretical models of the solar interior. The production of neutrinos is very sensitive to even the smallest variation of the physical conditions and the excellent agreement between observed and calculated neutrino fluxes also shows that our understanding of the solar interior is on solid ground, so I'm afraid that their premise is false and that their mechanism won't work. The 22-yr variation in rotation has not been observed by direct methods. We have data from Mt Wilson [and Wilcox] going back almost 40 years and there is no indication of a 22-yr variation above the noise. We can extract the equatorial rate from interplanetary magnetic field polarities which we have back to 1926 due to the Svalgaard-Mansurov effect, and they don't show any 22-yr variation either. |
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Post by vukcevic on Jun 13, 2009 18:22:25 GMT
 This may be just a coincidence, but if strong divergence (just started) of polar fields before minima is any guide, then this minimum is not done yet. Dr. Svalgaard ? |
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Post by lsvalgaard on Jun 14, 2009 7:56:07 GMT
This may be just a coincidence, but if strong divergence (just started) of polar fields before minima is any guide, then this minimum is not done yet. Dr. Svalgaard ? As most things people 'discover', this is just pure coincidence. It doesn't help that almost meaningless smoothing has been applied. Here are the polar fields for the past several years:  The red curve is for the South pole, the blue for the North pole. The brownish curve in the middle is the sum of N and S showing the annual variation, The light green curve is the theoretical, calculated expected variation. The WF refers to the effect of more than a thousand wildfires in California last summer, which dirtied the mirrors and created strong haze in the atmosphere, both of which results in an artificially low magnetic field. A similar effect is responsible for the polar fields being too low in 1976-1977 as explained on page 5 of www.leif.org/research/AGU%20Fall%202008%20SH51A-1593.pdfAmazingly enough, we get flak from several people that like the old [published] value better than we, who are actually measuring this and know the shortcomings of our instruments. Presumably the old [wrong] data points fit their ideas better... |
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Post by vukcevic on Jun 14, 2009 8:50:39 GMT
Dr. S Thanks for the detailed comment. Data I used is directly from WSO’s Solar Polar Field Strength table with filtered annual modulation: wso.stanford.edu/Polar.html#latestusing: Nf, Sf & Avgf. I assume that WSO does good job in maintenance of their data, I just plotted WSO table’s numerical values. Note from WSO: Each 10 days the usable daily polar field measurements in a centered 30-day window are averaged. A 20nhz low pass filtered values eliminate yearly geometric projection effects. |
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Post by lsvalgaard on Jun 14, 2009 9:13:26 GMT
Dr. S Thanks for the detailed comment. Data I used is directly from WSO’s Solar Polar Field Strength table with filtered annual modulation: wso.stanford.edu/Polar.html#latestusing: Nf, Sf & Avgf. I assume that WSO does good job in maintenance of their data, I just plotted WSO table’s numerical values. Note from WSO: Each 10 days the usable daily polar field measurements in a centered 30-day window are averaged. A 20nhz low pass filtered values eliminate yearly geometric projection effects. I know the WSO data well, as I discovered the polar field modulation while working there. The meaninglessness comes in when the filter is extended further in time than six months earlier from today. And even the filtered data show differences between N and S and many times. This is surely a pure coincidence. And spare me your snide assumptions as to how WSO does its job. |
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Post by vukcevic on Jun 14, 2009 9:46:49 GMT
It doesn't help that almost meaningless smoothing has been applied. .....Amazingly enough, we get flak from several people that like the old [published] value better than we, who are actually measuring this and know the shortcomings of our instruments. Presumably, the old [wrong] data points fit their ideas better... Dr. S Thanks for the detailed comment. ....... I assume that WSO does good job in maintenance of their data, I just plotted WSO table’s numerical values...... Dr. Svalgaard I am sorry to see that you totally misunderstood my comment about WSO data . It was prompted by your remark about “It doesn't help that almost meaningless smoothing has been applied”. I did not implied that WSO data is not good , actually it is opposite, but did not wish to contradict your observation about 'meaningless smoothing' , which is done by WSO. About the rest, I entirely agree. Most likely, it is a coincidence, but it is worth a note, just in case the N-S divergence effect is repeated. |
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Post by france on Jun 14, 2009 11:00:20 GMT
Dear Dr Svalgaard,
Is there any relationship between coronal holes and sunspots
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Post by lsvalgaard on Jun 14, 2009 14:27:55 GMT
It doesn't help that almost meaningless smoothing has been applied. .....Amazingly enough, we get flak from several people that like the old [published] value better than we, who are actually measuring this and know the shortcomings of our instruments. Presumably, the old [wrong] data points fit their ideas better... Dr. S Thanks for the detailed comment. ....... I assume that WSO does good job in maintenance of their data, I just plotted WSO table’s numerical values...... Dr. Svalgaard I am sorry to see that you totally misunderstood my comment about WSO data . It was prompted by your remark about “It doesn't help that almost meaningless smoothing has been applied”. I did not implied that WSO data is not good , actually it is opposite, but did not wish to contradict your observation about 'meaningless smoothing' , which is done by WSO. About the rest, I entirely agree. Most likely, it is a coincidence, but it is worth a note, just in case the N-S divergence effect is repeated. The meaninglessness comes not from the data but from people attaching any meaning to the last six months of filtered data. |
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Post by Ole Doc Sief on Jun 14, 2009 18:15:50 GMT
Dr Svalgaard- Isn't your prediction of low solar cycle base on solar polarity data? Does the current odd appearance of polarity changes kind of match what you would expect with such a wimpy cycle compared to previous years data  |
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k1tl
New Member
Posts: 7
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Post by k1tl on Jun 16, 2009 10:14:16 GMT
Dr Svalgaard:
Do coronal holes and sunspots have things in common?
What I'm trying to say is since there seems to be a lack of coronal hole activity, does this have an effect on lack of sunspot activity or is it just a normal phase the sun goes thru during min/max times. (i.e. more coronal hole activity during ss/max and less activity during ss/min)
Thanks.
Tom/k1tl...
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Post by lsvalgaard on Jun 16, 2009 12:59:51 GMT
Dr Svalgaard: Do coronal holes and sunspots have things in common? What I'm trying to say is since there seems to be a lack of coronal hole activity, does this have an effect on lack of sunspot activity or is it just a normal phase the sun goes thru during min/max times. (i.e. more coronal hole activity during ss/max and less activity during ss/min) Thanks. Tom/k1tl... coronal holes are often generated by decaying magnetic fields from sunspots, so in that sense they are related. |
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Post by francisco on Jun 23, 2009 16:32:19 GMT
Dr. Svalgaard, In the last couple of days the temperature of the solar wind has dropped to the bottom of the scale, as shown on link below: www.swpc.noaa.gov/ace/MAG_SWEPAM_7d.htmlWhat is the significance of this? Thanks in advance. |
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Post by france on Jun 24, 2009 23:06:32 GMT
I noticed that too but today
1 - temperature is higher at 19H
2 - at the same time speed of solar wind increases (near 500 km/s)
3 - and coronal hole is just by 1023 (may be 1022) sunspot
4 - and storms alert is current
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