At the risk of triggering a new sunspot by talking about it, I’ll cautiously mention that by GMT time midnight tomorrow, August 10th, we will possibly have a 30 day stretch of no sunspots at a time when cycle 24 has been forecast by many to be well underway. Here is the most recent (and auto updating) SOHO MDI image of the sun:
Spotless Days Count
(updated data from Spaceweather.com)
Current Stretch: 29 days
2009 total: 171 days (78%)
Since 2004: 682 days
Typical Solar Min: 485 days
Here is the latest data from NOAA’s Space Weather Prediction Center:
:Product: Daily Solar Data DSD.txt :Issued: 0225 UT 09 Aug 2009 # # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Please send comments and suggestions to SWPC.Webmaster@noaa.gov # # Last 30 Days Daily Solar Data # # Sunspot Stanford GOES10 # Radio SESC Area Solar X-Ray ------ Flares ------ # Flux Sunspot 10E-6 New Mean Bkgd X-Ray Optical # Date 10.7cm Number Hemis. Regions Field Flux C M X S 1 2 3 #--------------------------------------------------------------------------- 2009 07 10 68 13 60 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 11 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 12 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 13 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 14 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 15 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 16 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 17 66 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 18 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 19 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 20 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 21 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 22 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 23 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 24 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 25 69 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 26 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 27 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 28 69 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 29 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 30 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 07 31 69 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 01 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 02 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 03 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 04 66 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 05 66 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 06 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 07 68 0 0 0 -999 A0.0 0 0 0 0 0 0 0 2009 08 08 67 0 0 0 -999 A0.0 0 0 0 0 0 0 0
While it is possible that we’ll see a 30 day stretch of days with no sunspots, we have yet to complete a calendar month without a sunspot.
A year ago in August 2008, we initially had completed a sunspotless calendar month. But, as fate would have it, that distinction was snatched away at the very last moment by the folks in Belgium at SIDC based on one sketch of a plage cum sunspeck from Catainia observatory in Italy.
As Carly Simon once fabulously sung:
I know nothing stays the same
But if youre willing to play the game
Its coming around again
Kum Dollison (22:37:00) :
If that number has been decreasing, does that mean the atmosphere is likely to get cooler?
Absolutely. From solar max to solar min, the temperature will fall 0.05-0.1 degree. The average increase over a whole cycle would be about 0 degrees if the cycle was tiny, and about 0.05 degrees for a very large cycle. So, yes, solar cycles do make a difference. A tiny difference, hardly measurable.
PS According to the data I have from SIDC, there were 8 sunspots on the 23rd of July. So these 30 days have not been quite spotless.
Leif, you keep talking in “Solar Cycles.” I think it’s likely that the optimum number of years to study might be some other number. Perhaps, 5. Perhaps, 25. Perhaps, 15. Maybe, 30. That number comes up a lot – PDO?
It seems to me that heat would build up, until, at some point, after a certain number of below average sunspot years, and then it would start to dissipate. It seems like this could be a very Long cycle. Much more than 10, or 11 years.
“A tiny difference, hardly measurable.” I suspect you’d have to measure these things over thousands of years. But this is actually profoundly significant –
“From solar max to solar min, the temperature will fall 0.05-0.1 degree. ”
Now think of undiscovered solar “cycles” in the thousand year time frame. Think of this extra (atmospheric) heat as being a result of sunlight warming the oceans a little bit more than “normal” and then some of this heat being transfrerred in to the armosphere. But the way the oceans process this heat is not understood. I think you’d need to think of all these processes as taking maybe thousands of years. Some people ask how the oceans store away this heat but think about it… the bottom of the ocean contains solar heat, otherwise it would be frozen. I am assuming geo-thermal is not relevant and that may be wrong. How nuch solar heat energy does 1M cubed of incredibly dense deep water contain? How long ago did it fall on the ocean, some sunny day? How did it come to be stored at the bottom of the sea?
Lief,
Let me see if I have this right. We observe other stars with a patterned wobble in their predicted path, so we imply some planets around that star.
That means to me that the sun moves through space with a similar wobble – described I assume by the solar orbit around the SS barycenter. And you say the ellipticall earth-sun orbit is known to be an ellipse, which must mean for instance that at earth-sun appogee the earth is approximately the same distance from the sun as at every other appogee whether the sun is far from the barycenter on the earth side of the barycenter or on the far side. That would be at least a million mile potential difference and your description implies that difference is not observed. That must mean that the earth’s orbit actually follows a very complicated cycloid about the barycenter as the sun follows its smaller path around the barycenter.
Is that, can that, be true? From our point of view is the motion around the barycenter idea even observable?
It seems that more than 13 years have already passed since the last minimum, namely in spring to early summer of 1996.
And there were 8 sunspots on the 30th of July also – so I dont know how the figure of 30 spotless days was gotten.
Doah!
Leif, I know you don’t like the “The Sun Done It” theories; but, as a layman, I look up there at that big old ball of fire, and I say to myself, “Who Else Could’a Done It?”
I think we’ve just got caught up in looking at, maybe, too short of Time Frames. My hunch is we’ve gotta go, at least, a little bit past One Solar Cycle.
Kum Dollison (23:13:58) :
It seems to me that heat would build up, until, at some point, after a certain number of below average sunspot years, and then it would start to dissipate.
When you heat something up, it becomes warmer. Warmer stuff radiates more heat away, thus cools. So, heat doesn’t ‘build up’. There is a balance between what comes in and what goes out. Since the oceans [and the soil] can hold a large amount of heat any changes in the input will be dampened out and the output will be rather constant [Think of the constant temperature of a deep cave]. The output is what determines the temperature.
Roddy Baird (23:28:10) :
I think you’d need to think of all these processes as taking maybe thousands of years.
See reply above. Indeed, any changes will be smeared out over a long period and there will be very small changes in the output and hence temperature. These changes will be even smaller if the input changes are very small as we think they are.
Richard (22:54:33) :
Welcome to the arbitratry assignment stage.
How many spots?
(one of them is a dead pixel that has been with SOHO MDI Continuum for at least a year)
http://sohowww.nascom.nasa.gov//data/REPROCESSING/Completed/2009/mdiigr/20090723/20090723_1655_mdiigr_1024.jpg
http://sohowww.nascom.nasa.gov//data/REPROCESSING/Completed/2009/mdiigr/20090723/20090723_1736_mdiigr_1024.jpg
This one, July 10, 2009 earned a 9 on the SIDC scale:
starting image:
http://sohowww.nascom.nasa.gov//data/REPROCESSING/Completed/2009/mdiigr/20090710/20090710_0721_mdiigr_1024.jpg
ending image:
http://sohowww.nascom.nasa.gov//data/REPROCESSING/Completed/2009/mdiigr/20090710/20090710_2224_mdiigr_1024.jpg
Mary Shelly’s reports from 1816 are not a good example for the Dalton minimum as in this year Mount Tambora’s eruption caused a severe volcanic winter.
Leif usually makes a mention of using 10.7 cm radio flux as a better proxy of SSN than actual SSN numbers. Oddly enough, the 10.7 cm radio flux has been trending down for 3 months after peaking in May. This is interesting if you though SC24 had finally kicked off in May. Looking at the flux data I’m wondering if we have reached solar minimum yet ?
On a temperature verses SSN correlation…..
A simple graph tells a story.
http://www.woodfortrees.org/plot/sidc-ssn/from:1840/mean:12/normalise/plot/hadsst2gl/mean:12/normalise/from:1840
– From this data it looks like the relationship follows the peaks of the cycle, meaning a drop in temp being noticed more after 2012 – provided SC24 is a low peak.
“Richard (22:54:33) :
PS According to the data I have from SIDC, there were 8 sunspots on
the 23rd of July. So these 30 days have not been quite spotless.”
The sunspot number is not the number of sunspots. It is derived by considering the number of groups of spots and the number of spots in each group, multiplied by a site-specific ‘fudge-factor- to equalize the differing viewing capabilities. A value of 8 represents a spot so small than some sites could not see it.
Lee (23:42:50) :
That must mean that the earth’s orbit actually follows a very complicated cycloid about the barycenter as the sun follows its smaller path around the barycenter.
Is that, can that, be true? From our point of view is the motion around the barycenter idea even observable?
It would be more correct to say that Sun and the Earth together orbit the barycenter. Or even better: all the bodies in the solar system move under their mutual gravitational attraction, they are all in free fall. At any moment one can calculate the center of mass of the constellation of bodies [call it the Barycenter]. It is convenient to consider that point as the origin of a coordinate system, and seen from afar that will be the ‘fixed’ point of the solar system as it moves through the galaxy. Perhaps this analogy is helpful: a man falls off a tall building, as he falls [ignoring air resistance] he is in free fall and feels no forces on him. His flails his arms and legs in terror and perhaps tumbles head over heel. His center of gravity follows a smooth curve as he falls but when you look at him you see his various parts moving around.
Ozzie John (03:12:20) :
Looking at the flux data I’m wondering if we have reached solar minimum yet ?
It is still higher than it was in December, and since there are more SC24 spots now than SC23 spots, minimum is sometime in the past.
On a temperature verses SSN correlation…..
A simple graph tells a story.
The green and the red curve do not seem to be correlated at all. The green curve has enough little wiggles on it to match some wiggles on the red curve somewhere. But, the trend of the red and green curves are completely different. Now, you can get a match on the trend by this simple procedure: divide the data in two halves, the first half and the last half. Compute the average red and green values for the two divisions. Then you’ll find that both pairs of points trend up, and presto, you have established a correlation.
jtom (04:32:04) :
The sunspot number is not the number of sunspots.
Stop it, you’re killing me.
So, SOHO caught a soso, but the yoyo drew as yoho, but couldn’t photo the mojo.
but 13 days earlier, a 9 was counted and everybody saw it.
Smokin’ !
Kum Dollison (00:30:40) :
I think we’ve just got caught up in looking at, maybe, too short of Time Frames. My hunch is we’ve gotta go, at least, a little bit past One Solar Cycle.
There is no doubt that the ‘Sun does it’. The question is ‘how much?’
Consider this thought experiment: We settle the Sun in at its minimum TSI, say 1365, constantly for a thousand years [time enough for this to settle, perhaps, otherwise we just let it sit longer]. Then we increase TSI to 1366.5 and keep it there for another thousand years. The question we now ask is what will be the temperature increase due to this increase of TSI. My answer is 0.07 degrees. If the two intervals are a lot shorter and follow each other cyclically and the oceans and the rocks are dampening out any changes, the variations in temperature with the cycles will be smaller still.
“Leif Svalgaard (08:26:31) :
Ozzie John (03:12:20) :
Looking at the flux data I’m wondering if we have reached solar minimum yet ?
It is still higher than it was in December, and since there are more SC24 spots now than SC23 spots, minimum is sometime in the past.”
Given that 200 years ago magnetograms did not exist it was not known which spots belonged to which cycle during minimum (only latitude could tell, but even this is not an accurate method as SC 23 has shown), and so which cycle the magnetogram indicates today is irrelevant if you want to keep sunspot cycle data recording consistent.
Sunspot Minimum has not been reached, there is no official statement which has declared minimum. December 2008 is a CANDIDATE month for minimum. This does not mean that January 2009 cannot be minimum.
Currently as August progresses quietly and if the streak continues January 2009 may very well be the new candidate for month of minimum.
Flux has not reached 74 since 17 May and has not reached 70 since 9 July.
I think it’s now been 30 days assuming GMT midnight (0000 Z) today meant 0100 B(ritish)S(ummer)T(ime) today (e.g. based on “spring ahead”).
Mr. Alex (10:01:31) :
Sunspot Minimum has not been reached, there is no official statement which has declared minimum. December 2008 is a CANDIDATE month for minimum.
There are many minima, every type of solar activity, sunspots, number of old vs new spots, magnetic field, heliospheric tilt angle, cosmic rays, ephemeral regions, radio flux, TSI, etc all have minima at different times. And there is no official minimum.
The often-used definition based on the smoothed sunspot number is about the worst one of the bunch, as far a the ‘real’ minimum is concerned. Imagine an interval of 12 months of which the first six [and many months before] only had spots of cycle N and the last six month [and many months thereafter] only had spots of cycle N+1, then it would make sense to put the minimum in the middle, no matter what the sunspot numbers were. Having the N+1 cycle spots ramping up at different rates would move the smoothed ‘minimum’ accordingly, but that movement would be completely artificial.
Mr. Alex (10:01:31) :
It’s common to hear that Solar activity is very low these days.
It’s also been very slow to change.
All ahead slow, bow planes at 5 degrees, rig for silent running.
It’s Monday, August 10, 2009, and that’s the way it is.
Maybe the last big sc24 sunspot was its last breath?
To me it seems like all the ‘pores’ were welded together and produced the last mature sunspot and now we’re left without the pores.
Leif Svalgaard (09:17:55) : Except, it is not valid. If there is a relationship [there is no statistically valid one], it is the other way around: http://www.leif.org/research/Cycle%20Length%20Temperature%20Correlation.pdf
Leif, whats the green lines represent, and shouldn’t you be implementing some corrections on the temp lines based on recent exposes of NOAAs fraudulent ‘corrections’ being responsible for most all claimed warming?
“Leif Svalgaard (10:49:20) :
There are many minima”…
“And there is no official minimum.”
True, but here the minimum I refer to deals with the official international sunspot number: http://www.solen.info/solar/
Indicating that Dec 2008 is “very likely the sunspot minimum” should August bring good activity as seen in June/May.
It may be the worst, but it is the most accepted.
Solar Cycle 23 is probably over, but just because SC 23 has ended doesn’t mean that quiet times won’t continue, (hence “minimum” continues).
“then it would make sense to put the minimum in the middle”
Ah, but then one must define what ratio between N+1 and N spots constitutes ‘the middle’, the last pseudospot recognized by SIDC in July was Cycle 23.
Flux may be a better indicator. What are your thoughts with regards to the downward trend in flux since May? Any ideas as to when it may begin to rise uniformly to maximum? Any precursors indicating a rise?