|
|
Post by lsvalgaard on Mar 25, 2010 0:52:41 GMT
Good morning! You are correct. What is needed is more data (and patience). By the way, do the other investigators post their magnetic field strength results?? G. The Layman's sunspot count measures the darkness ratio of all SC24 spots. The recent trend is up and this month's update will probably be the same. hard to see a trend here. one problem is the procedure. is the value the darkest one of a group or is there a value for every spot within the group. only more data will tell, but the procedure has to be explained fully. |
|
jinki
Level 3 Rank
Posts: 123
|
Post by jinki on Mar 25, 2010 1:10:36 GMT
The Layman's sunspot count measures the darkness ratio of all SC24 spots. The recent trend is up and this month's update will probably be the same. hard to see a trend here. one problem is the procedure. is the value the darkest one of a group or is there a value for every spot within the group. only more data will tell, but the procedure has to be explained fully. The trend shows that the bigger groups are not losing darkness, the lower values belong to very small groups. This I think is the main point, the darkness ratio seems to be linked with group size. Random selection will pick up smaller groups and may take some time before the real trend is noticed. The procedure is laid out on the website, but my understanding is that the pixels are measured off the Continuum image, using the green spectrum. The whole area is measured and the proportion of pixels in the 0-35 range is compared with the whole area. |
|
|
|
Post by lsvalgaard on Mar 25, 2010 1:26:49 GMT
hard to see a trend here. one problem is the procedure. is the value the darkest one of a group or is there a value for every spot within the group. only more data will tell, but the procedure has to be explained fully. The trend shows that the bigger groups are not losing darkness, the lower values belong to very small groups. This I think is the main point, the darkness ratio seems to be linked with group size. Random selection will pick up smaller groups and may take some time before the real trend is noticed. The procedure is laid out on the website, but my understanding is that the pixels are measured off the Continuum image, using the green spectrum. The whole area is measured and the proportion of pixels in the 0-35 range is compared with the whole area. It is always dangerous to compare data not made the same way. L&P do not say that the largest spots are getting weaker. The sunspot number is SSN = 10*Groups + spots. A large group may have a couple big spots and a hundred tiny ones [which are all counted]. So, if the tiniest half was eliminated the whole area would not be affected much but the SSN would be cut almost in half. This is the 'real' L&P effect IMO. BTW, during the Maunder Minimum all spots reported were large spots. There can be another reason that the F10.7 and the SSN during cycle 23 relate differently than before: the SSN[23] would be wrong [underestimated, but not because of L&P - because of errors or changes at SIDC]. Or that what we see is a combination of both error and L&P. It is too early to speculate too much. This includes dissing the effect. You mention that "Random selection will pick up smaller groups". This is not really the case, as the random selection is not of groups but of days where observations are made, and on the selected days all spots are measured, big and small alike. |
|
|
|
Post by Bob k6tr on Mar 25, 2010 2:26:11 GMT
This new Spot Group coming around the corner looks mighty dark yet only contains 5 spots. If Bill Livingston has scope time this week this could be an interesting reading.
|
|
|
|
Post by sranderson on Mar 25, 2010 3:02:10 GMT
Unfortunately you have assumed that L&P have proven their thesis that Magnetic Intensity of Sunspots will continue to drop. The fact of the matter is although Bill Livingston took his first measurements in 1995 he did not record measurements in any quantity until 2003 well after the peak of Cycle 23. L&P made 56 measurements in 2001 and 135 measurements in 2002. Combined with the changes seen in the 10.7 flux to sunspot ratio, it is reasonably compelling that something unusual is going on. The layman's measurements do not cover enough time yet to be very significant. Time will tell. By the end of 2010 we should know more.  |
|
|
|
Post by lsvalgaard on Mar 25, 2010 4:23:31 GMT
Unfortunately you have assumed that L&P have proven their thesis that Magnetic Intensity of Sunspots will continue to drop. The fact of the matter is although Bill Livingston took his first measurements in 1995 he did not record measurements in any quantity until 2003 well after the peak of Cycle 23. L&P made 56 measurements in 2001 and 135 measurements in 2002. Combined with the changes seen in the 10.7 flux to sunspot ratio, it is reasonably compelling that something unusual is going on. The layman's measurements do not cover enough time yet to be very significant. Time will tell. By the end of 2010 we should know more. And nobody assumes anything proven. Something is going on, and we don't know yet exactly what. |
|
jinki
Level 3 Rank
Posts: 123
|
Post by jinki on Mar 25, 2010 5:17:48 GMT
Unfortunately you have assumed that L&P have proven their thesis that Magnetic Intensity of Sunspots will continue to drop. The fact of the matter is although Bill Livingston took his first measurements in 1995 he did not record measurements in any quantity until 2003 well after the peak of Cycle 23. L&P made 56 measurements in 2001 and 135 measurements in 2002. Combined with the changes seen in the 10.7 flux to sunspot ratio, it is reasonably compelling that something unusual is going on. The layman's measurements do not cover enough time yet to be very significant. Time will tell. By the end of 2010 we should know more. Because the Laymans method is image based, history can be revisited. There is reference to images measured in 2005 (before that the image quality changes dramatically) that have readings in the low 80% range. Current measurements are not that far away. The measurements quoted via L&P, were they daily readings of the same group or did they measure 56 separate individual groups in 2001? |
|
|
|
Post by lsvalgaard on Mar 25, 2010 5:47:19 GMT
L&P made 56 measurements in 2001 and 135 measurements in 2002. Combined with the changes seen in the 10.7 flux to sunspot ratio, it is reasonably compelling that something unusual is going on. The layman's measurements do not cover enough time yet to be very significant. Time will tell. By the end of 2010 we should know more. Because the Laymans method is image based, history can be revisited. There is reference to images measured in 2005 (before that the image quality changes dramatically) that have readings in the low 80% range. Current measurements are not that far away. The measurements quoted via L&P, were they daily readings of the same group or did they measure 56 separate individual groups in 2001? They had telescope time on 14 days spread through the year and on some occasions the same group was remeasured. Now, it is important that they did not measure groups but single spots that were members of groups. It may be significant that the new group that has just come round the East limb doesn't have any [visible] small spots in it. The small spots would be the first to disappear if L&P are correct... |
|
grian
Level 2 Rank
Posts: 50
|
Post by grian on Mar 25, 2010 10:42:28 GMT
It may be significant that the new group that has just come round the East limb doesn't have any [visible] small spots in it. The small spots would be the first to disappear if L&P are correct... Or not. Seen plenty of groups like this over the past 30 years of observing. |
|
|
|
Post by Bob k6tr on Mar 25, 2010 14:06:18 GMT
Unfortunately you have assumed that L&P have proven their thesis that Magnetic Intensity of Sunspots will continue to drop. The fact of the matter is although Bill Livingston took his first measurements in 1995 he did not record measurements in any quantity until 2003 well after the peak of Cycle 23. L&P made 56 measurements in 2001 and 135 measurements in 2002. Combined with the changes seen in the 10.7 flux to sunspot ratio, it is reasonably compelling that something unusual is going on. Cycle 23 double peaked . The first occurred in March 2000 the second occurred in March 2003. Thus far Bill Livingstons data spans the declining part of one cycle with a handful of measurements since Cycle 24 started producing spots in any volume a few months ago. In order for Livingston's postulation to stand up his research is going to have to separate it from typical Solar Cyclic Activity. That will require data from the rise phase of Cycle 24 Take a good look at the new region, 1057, which has just rotated into view. It has a heavy MDI signature yet is barely larger than 1056 when viewed at 304A. 1056 has decayed into a spotless plague. You don't need Zeeman Splitting to verify that 1057 is magnitically intense. |
|
|
|
Post by lsvalgaard on Mar 25, 2010 14:12:49 GMT
It may be significant that the new group that has just come round the East limb doesn't have any [visible] small spots in it. The small spots would be the first to disappear if L&P are correct... Or not. Seen plenty of groups like this over the past 30 years of observing. how many? |
|
radun
Level 3 Rank
Posts: 152
|
Post by radun on Mar 25, 2010 15:41:35 GMT
Daily synoptic chart from the WSO could be used as a rough guide.  |
|
|
|
Post by Bob k6tr on Mar 26, 2010 0:43:55 GMT
L&P made 56 measurements in 2001 and 135 measurements in 2002. Combined with the changes seen in the 10.7 flux to sunspot ratio, it is reasonably compelling that something unusual is going on. The layman's measurements do not cover enough time yet to be very significant. Time will tell. By the end of 2010 we should know more. And nobody assumes anything proven. Something is going on, and we don't know yet exactly what. No assumptions ? Well presumptions then. Let's take a look. arxiv.org/PS_cache/arxiv/pdf/1003/1003.4281v1.pdf On Page 2 Figure 2 You say that two Epochs were selected 1951-1988 and 1996-2009. The latter was selected because it represents the last complete Solar Cycle and the most recent data which is logical. But the selection of the start and stop points for the first epoch is to say least curious. You state the parameters were selected because it was "surprisingly precise and stable". But what immediately jumps out at the casual observer is the overall intensity of Solar Activity during this period. Cycle 19, 1954 to 64, was the highest recorded Sunspot Cycle ever. Cycle 21 the second highest recorded. And Cycle 22, of which you only use the early years, is the 4th most intense ever recorded. Of the 3.5 Cycle that are encompassed in the first epoch only Cycle 20 compares favorably with Cycle 23 in terms of intensity. Comparing the SSN/SFI ratio between those two cycles alone would give more accurate results. |
|
grian
Level 2 Rank
Posts: 50
|
Post by grian on Mar 26, 2010 8:32:13 GMT
Or not. Seen plenty of groups like this over the past 30 years of observing. how many? Enough not to think this group is unusual. Would probably take me a week of going through all my observing notebooks to give you a definitive number. Suffice to say that's an exercise I'm not going to do. |
|
|
|
Post by lsvalgaard on Mar 26, 2010 13:43:43 GMT
And nobody assumes anything proven. Something is going on, and we don't know yet exactly what. No assumptions ? Well presumptions then. Let's take a look. arxiv.org/PS_cache/arxiv/pdf/1003/1003.4281v1.pdf On Page 2 Figure 2 You say that two Epochs were selected 1951-1988 and 1996-2009. The latter was selected because it represents the last complete Solar Cycle and the most recent data which is logical. But the selection of the start and stop points for the first epoch is to say least curious. You state the parameters were selected because it was "surprisingly precise and stable". But what immediately jumps out at the casual observer is the overall intensity of Solar Activity during this period. Cycle 19, 1954 to 64, was the highest recorded Sunspot Cycle ever. Cycle 21 the second highest recorded. And Cycle 22, of which you only use the early years, is the 4th most intense ever recorded. Of the 3.5 Cycle that are encompassed in the first epoch only Cycle 20 compares favorably with Cycle 23 in terms of intensity. Comparing the SSN/SFI ratio between those two cycles alone would give more accurate results. There is a typo [repeated] in the paper. The interval [as indicated on the Figure is 1951-1990, not 1951-1988. The 1951 is just the beginning of the Japanese data. The 1990 and 1996 points were selected not based on solar cycles, but simply to provide some separation of the data into two classes. There did not seem to be a sharp discontinuity so we were not sure where in the 1991-1995 interval to place the separation year. Better to have a gap there so we don't blend the two populations. In addition, both stations moved during that period, the Canadian in 1991 and the Japanese one in 1994. You can see from Figure 3 that cycle 19 and cycle 20 behave identically in spite of their very different sizes. |
|
