Sol has been without a cycle 24 spot since January 13th. Today the spotless streak was broken with this high latitude and correct polarity spot. The current sunspot number is now at 12 according to SWPC.
The SOHO Magnetogram image below shows how the North-South polarity is oriented:
The real question is: how long will it last? Most of the cycle 24 spots we’ve seen so far have very short lifetimes, winking out in a day or two.
Geoff Sharp
Thanks for the abstracts and diagram, but I am confused and perhaps not seeing your point. Are you suggesting the 14C solar proxy data can be influenced by actions outside of those that create sunspots?
As an enhanced Biological response to increased uv.
Geoff Sharp (21:18:56) :
SC24 could be quite a bit lower than you have predicted.
‘could’ is what we call a ‘weasel word’
Your power spectrum is as expected over the short time frame, how does the 100 year period look over 11000 years?
Then, of course, it shows the Gleissberg cycle even better at 87.4 years: http://www.leif.org/research/FFT-INTCAL98-14C.png
The data is the 14C delta per mil. The same data used by Usokin/Solanky et al. It has 10 years resolution so cannot show periods shorter than twice that [20 years]. If one removes a running mean [or otherwise violate/massage the data, one can get rid off the rising power towards the longer periods.
Do you have a theory on what drives the so called Gleissberg cycle?
Many. Here is one: http://adsabs.harvard.edu/full/1999A&A…346..295P
Leif Svalgaard (22:26:41) :
‘could’ is what we call a ‘weasel word’
Thats what “we” call a very cocky attitude…lets hope you dont fall in a heap. You have a lot riding on it.
Then, of course, it shows the Gleissberg cycle even better at 87.4 years
As expected, the 14C records along with angular momentum records clearly show a smaller period between the highs and lows of solar activity as we go back in time. This side of the MWP is very different to the other side.
Do you have a theory on what drives the so called Gleissberg cycle?
Many. Here is one: http://adsabs.harvard.edu/full/1999A&A…346..295P
More models…but a theory none the less. From what I can glean quickly this paper suggests differential rotation or torsional oscillation is the driver of the Gleissberg cycle, but doesnt offer much in the way of what changes this oscillation. A lot of science has recognized patterns and changes in the Sun, but not found the underlying cause. As can been seen in current Doppler images the rotation rate of the Sun is increasing, this looks to happen when we have grand minima. This phenomena also occurs when we have angular momentum disturbance and I suggest this is whats behind the Gleissberg cycle.
http://users.beagle.com.au/geoffsharp/doppler.jpg
Geoff Sharp (01:13:24) :
“‘could’ is what we call a ‘weasel word’”.
as are ‘quite’ and ‘a bit’ …
As expected, the 14C records along with angular momentum records
So no longer an enigma…
As can been seen in current Doppler images the rotation rate of the Sun is increasing, this looks to happen when we have grand minima.
The Doppler images do not show ‘solar rotation’, but ‘winds’ in the atmosphere, much as the Earth has its trade winds [although the mechanism is different]. These winds [zonal flows as Rachel Howe correctly calls them] are caused by activity, not the other way around.
This phenomena also occurs when we have angular momentum disturbance and I suggest this is whats behind the Gleissberg cycle.
So, low angular momentum speeds the Sun up? and occurs every 87 years…
Leif Svalgaard (05:50:06) :
So no longer an enigma…
perhaps not to me….but how you guys on the dynamo side come to acknowledge this pattern is very amusing.
The Doppler images do not show ’solar rotation’, but ‘winds’ in the atmosphere, much as the Earth has its trade winds [although the mechanism is different]. These winds [zonal flows as Rachel Howe correctly calls them] are caused by activity, not the other way around.
Thats one way at looking at the data…over the whole surface that might be a good explanation. But if we look at the equator where differential rotation due to latitude has little effect, there is a clear sign of rotation change.
So, low angular momentum speeds the Sun up? and occurs every 87 years…
Not even close…please learn the basics before embarrassing yourself.
Geoff Sharp (06:35:16) :
“So, low angular momentum speeds the Sun up? and occurs every 87 years…”
Not even close…please learn the basics before embarrassing yourself.
Geoff Sharp (23:51:29) :
Less grand minima action coupled with increased angular momentum leads to higher solar activity as we have seen recently
Is presumably ‘the basics’: high Angular Momentum [AM] => high solar activity, thus low AM => low solar activity, and is associated with speeded up rotation, and this happens every 87 years.
Leif Svalgaard (07:59:24) :
High AM = high solar activity, but also causes grand minima when J/S angles are favorable (very common). Low AM coincides with low cycles (early 1900’s) but does not cause grand minima. Low AM is always when N/U are apposing.
The “center” of high AM is roughly 172 years apart, with windows of opportunity 40 years each side (partial line up). This gives us the Gleissberg type gap between high solar activity/grand minima that occur together. The gap changes depending on if all grand minima opportunities are taken. Before the MWP the J/S angles spread out the available grand minima type disturbances (green and red squares on 14C graph) You wont find solar high activity peaks or grand minima during times of low AM.
http://users.beagle.com.au/geoffsharp/solanki_sharp_detail.jpg
http://users.beagle.com.au/geoffsharp/ultimate_graph2.jpg
Sorry…i’m kind of in the dark here. What creates a “Cycle 24 Spot” and how long do they usually last?
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Frank B.
Immigration lawyer