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Post by nautonnier on Dec 22, 2018 20:43:08 GMT
Prediction of the strength and timing of sunspot cycle 25 reveal decadal-scale space environmental conditions www.nature.com/articles/s41467-018-07690-0"Our ensemble forecast indicates cycle 25 would be similar or slightly stronger than the current cycle and peak around 2024. Sunspot cycle 25 may thus reverse the substantial weakening trend in solar activity which has led to speculation of an imminent Maunder-like grand minimum and cooling global climate." Leif Svalgaard’s forecast. Though I have no wager in this contest of prognostication, I am interested in the outcome and believe the “Boy Scouts” axiom to be sound advice. There is probably no other forecasting system where so few cases are used as predictors for the future. I have seen 20 high tides so I can categorically predict the level of the next one would be laughed out of court. Yet a system with considerably more variables can be forecast precisely?
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Post by nonentropic on Dec 22, 2018 20:54:30 GMT
The real point is that the prediction for cycle 25 is still considerably below 22 and 23 but about as weak as 24.
It would still indicate which forcing was dominant and potentially extend the pause should the bulk on this site be correct.
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Post by sigurdur on Dec 28, 2018 6:48:33 GMT
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Post by nonentropic on Dec 28, 2018 20:46:52 GMT
but they project 25 well below 22 and 23.
In a way we need to be careful what we wish for here if 25 is weakish as per 24 has been then the climate may well settle back a little and in time even the spin doctors will have trouble flogging the dead horse.
A reality say 1C lower than now would be disappointing for my lifestyle and many others.
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Post by missouriboy on Dec 29, 2018 1:47:32 GMT
The real point is that the prediction for cycle 25 is still considerably below 22 and 23 but about as weak as 24. It would still indicate which forcing was dominant and potentially extend the pause should the bulk on this site be correct. For an analog one need look no further back than the relationship between SC 12 and SC13 ... the 1880s ,.. which was followed by two more low cycles. Not the end of the world ... my grand parents survived ... But their generation wasn't called on to feed how many billions?
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Post by nautonnier on Dec 29, 2018 10:52:24 GMT
The real point is that the prediction for cycle 25 is still considerably below 22 and 23 but about as weak as 24. It would still indicate which forcing was dominant and potentially extend the pause should the bulk on this site be correct. For an analog one need look no further back than the relationship between SC 12 and SC13 ... the 1880s ,.. which was followed by two more low cycles. Not the end of the world ... my grand parents survived ... But their generation wasn't called on to feed how many billions? I understand the wish to use analogues but the sample size is very small and the Solar system is a chaotic system. Even 'simple' closely repeating values can lead to complex behaviors that repeat slightly differently each time and sometimes significantly differently. See the 'Tinkerbell' chaotic map below (which should be in 4 Dimensions) We are told both that the solar system is chaotic and yet deterministic maths is being used to calculate its behavior as it is 'close enough'. However, that difference between 'precisely correct' and 'close enough' is the source of chaos - as Lorentz first showed. That Solar system behavior affects the equally chaotic behavior of the Solar 'dynamo(s)' and Solar atmosphere - again a behavior that is calculated deterministically as it is 'close enough'. So I would not be at all surprised if SC-25 was totally different to expectations based on previous behaviors as 'bary' (cough) will tell you small differences in the planetary positions will change the progress of the change from SC-24 to SC-25 compared to SC-12 to SC-13. We will not know if these differences will cause a move away from an attractor or a different orbit around it until it has happened.
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Post by duwayne on Dec 30, 2018 16:32:25 GMT
Science is about making predictions.
Before Cycle 23 ended many solar scientists issued predictions on the magnitude of Cycle 24. These predictions were all over the place.
(Using the logic of certain climate “scientists” an average of these predictions would provide a high level of certainty.)
Almost every Cycle 24 prediction by a solar scientist was way too high.
The solar scientists who didn’t make predictions added little value. Those who made incorrect predictions added value because they showed that various theories which made sense based on historical data were wrong. Svalgaard, and anyone else who made a correct prediction has added value because they may have found the answer.
Holloway, the Nasa solar scientist, had one of the worst early Cycle 24 predictions. But I give him credit for adopting Svalgaard’s methodology for his Cycle 25 prediction. The prediction isn't a sure thing but I see the science advancing.
(NASA climate “scientists” have been known to change the data to make their prediction seem accurate and label the person with the accurate prediction a denier and do their best to get him fired. And then they continue to make the same inaccurate widely varying predictions and claim the average is worth something.)
Nautonnier, all this brings me to this questio. Do you have a prediction for Cycle 25 based on barycenter movements? If there are no predictions, why should I pay attention?
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Post by nautonnier on Dec 30, 2018 17:50:58 GMT
Science is about making predictions. Before Cycle 23 ended many solar scientists issued predictions on the magnitude of Cycle 24. These predictions were all over the place. (Using the logic of certain climate “scientists” an average of these predictions would provide a high level of certainty.) Almost every Cycle 24 prediction by a solar scientist was way too high. The solar scientists who didn’t make predictions added little value. Those who made incorrect predictions added value because they showed that various theories which made sense based on historical data were wrong. Svalgaard, and anyone else who made a correct prediction has added value because they may have found the answer. Holloway, the Nasa solar scientist, had one of the worst early Cycle 24 predictions. But I give him credit for adopting Svalgaard’s methodology for his Cycle 25 prediction. The prediction isn't a sure thing but I see the science advancing. (NASA climate “scientists” have been known to change the data to make their prediction seem accurate and label the person with the accurate prediction a denier and do their best to get him fired. And then they continue to make the same inaccurate widely varying predictions and claim the average is worth something.) Nautonnier, all this brings me to this questio. Do you have a prediction for Cycle 25 based on barycenter movements? If there are no predictions, why should I pay attention? You do not have to pay attention at all However, you should note that falsification of a hypothesis does not require the provision of an alternate hypothesis. Nevertheless, had I the time I would be looking at the position of the solar system barycenter and its motion compared to the rotation of the Sun. This is effectively also assessing the various planetary motions for the 50 years or so - a little more than 22years either side of the current solar minimum. The dynamo would appear to be driven by both the rotation of the Sun and the momentum/inertia of the layers of the Sun to changes in rotation and orbit around the barycenter. Disruption of the angular momentum and magnetic fields of the layers may well lead to the dynamo increasing or reducing the Solar radiation/magnetic/electric field output. It is obvious that there are 11/22 year cycles and other cycles that appear to be 400 years and ~1100 years. But it is a chaotic system so we need to know what causes these cycles, in the same way that we have identified the moon's gravitation and 'orbit' as the main (but not the only) reason for ocean tides. If we were able to quantify these influences on the Sun then we may be able to identify the reason for the variances in the Solar cycles and can then predict/forecast what we expect in the same way we can forecast a neap or king tide. I have a suspicion that this type of forecasting is what Theo has been doing in 'astrometeorology'. In meteorology you can get a reasonable 24 hr forecasting success rate just by saying: it will be like yesterday; or for longer periods, by looking back at 'analogs' just say this is what it did last time so expect that to happen. But this type of analog first tends to make use of several analog years and is overlaid by an understanding of why the weather is likely to follow a certain trajectory. Analogs of past Solar cycles are few and the metrics used to compare them limited to what was measured in the past and we now know that there is a considerable coupled chaotic behavior: this was my reason for the caution. I would also caution pure 'astrometeorology' for a similar reason that it may not take full account of the chaos of the systems that are interacting. As Lorentz showed minor errors can lead to a rapid divergence of forecast from reality. But at least in astrometeorology there may be fewer unknown unknowns. You asked for a hypothesis leading to a prediction - all I can provide is the reasoning above as I have a day job . But you still don't have to listen or take note.
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Post by missouriboy on Jan 2, 2019 18:11:12 GMT
And Meanwhile ... the monitoring of instrumental readings and comparison to analogs goes on ... as it must if those who forecast are to be graded. December is in for the standard solar metrics. SC24 continues to look more like SC12 than SC20 in terms of solar flux and spotless days. Spotless days for the entry months to SC20 were much greater than the exit months preceding SC21 ... perhaps an indicator of the stronger solar cycle to follow? Solar Cycle 12 was followed by a very slightly stronger cycle ... similar to Dr Svalgaard's prediction for SC25. I do not have an explanation for why monthly sunspot numbers for SC12 are so much higher than SC24, while Flux values are very similar. They come from the same database. Note: years on the x-axis are for SC12.
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Post by sigurdur on Jan 3, 2019 18:34:34 GMT
And Meanwhile ... the monitoring of instrumental readings and comparison to analogs goes on ... as it must if those who forecast are to be graded. December is in for the standard solar metrics. SC24 continues to look more like SC12 than SC20 in terms of solar flux and spotless days. Spotless days for the entry months to SC20 were much greater than the exit months preceding SC21 ... perhaps an indicator of the stronger solar cycle to follow? Solar Cycle 12 was followed by a very slightly stronger cycle ... similar to Dr Svalgaard's prediction for SC25. I do not have an explanation for why monthly sunspot numbers for SC12 are so much higher than SC24, while Flux values are very similar. They come from the same database. Note: years on the x-axis are for SC12. Interesting, the charts are rattling.
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Post by Ratty on Jan 4, 2019 5:07:24 GMT
[ Snip ] Interesting, the charts are rattling. TTL. I thought it was my bones ....
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Post by nautonnier on Jan 19, 2019 11:33:03 GMT
Interesting discussion by Nir Shaviv on Sun's effect on climate and how Cosmic Rays affect weather (H/T Oldbrew/TallblokesTalkshop)
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Post by nautonnier on Jan 20, 2019 12:57:45 GMT
Another in the series
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Post by duwayne on Jan 20, 2019 20:04:10 GMT
The "Maunder Minimum soon" predictions have some logic behind them but still haven't found much support in the solar science community. Since Cycle 24 has proven nearly all theories for predicting solar activity to be wrong, I thought we might see some new thinking and perhaps more support for a near-term "dimming" of the sun.
The fact that some scientists on the margin of solar science are confident enough to make specific predictions for Cycle 25 and 26, ie, Cycle 25 half as active as Cycle 24 and close to zero activity in Cycle 26, the odds of something happening seem to be a little higher. But even after the new studies and in spite of the very cold and snowy weather in the northern US this week, I'm still not quite ready to put it in my long-term global temperature prediction.
Is anyone here convinced there's a Maunder Minimum just ahead?
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Post by Ratty on Jan 20, 2019 23:08:11 GMT
The "Maunder Minimum soon" predictions have some logic behind them but still haven't found much support in the solar science community. Since Cycle 24 has proven nearly all theories for predicting solar activity to be wrong, I thought we might see some new thinking and perhaps more support for a near-term "dimming" of the sun. The fact that some scientists on the margin of solar science are confident enough to make specific predictions for Cycle 25 and 26, ie, Cycle 25 half as active as Cycle 24 and close to zero activity in Cycle 26, the odds of something happening seem to be a little higher. But even after the new studies and in spite of the very cold and snowy weather in the northern US this week, I'm still not quite ready to put it in my long-term global temperature prediction. Is anyone here convinced there's a Maunder Minimum just ahead? Nobody in Australia.
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