Friday, December 13, 2019

Keeping an Eye On the Quiet Sun

An interesting post on Watts Up With That (WUWT) yesterday pointed out that we're about to cross a historic milestone:  2019 will be the year with the most zero-sunspot-days in the satellite era.  As of yesterday (12/12), when this was posted:
So far this year the sun has been blank (i.e., no visible sunspots) for 266 days and, barring any major surprises, it’ll reach 269 days early next week which will be the quietest year in terms of sunspots since 1913 when the sun was spotless for 311 days. In fact, the current stretch of consecutive spotless days has reached 29 and for the year the sun has been blank 77% of the time. The current record-holder in the satellite era for spotless days in a given year is 2008 when the sun was blank for 268 days making the 2008-2009 solar minimum the deepest since 1913. 
We've talked about this being the weakest sunspot cycle in over a hundred years, and how this is a mechanism for the way solar activity can impact climate.  The mechanism is counterintuitive to many people, but was first proposed by Henrik Svensmark of the Danish National Space Institute in Copenhagen.  The Earth is constantly bombarded by galactic cosmic rays; high energy radiation from sources elsewhere in the galaxy and even beyond.  The solar wind, the constant push of charged particles ejected by reactions in the sun, ordinarily keeps some of those particles from reaching the earth.  During solar minima, the solar wind weakens and more charged particles make it into the atmosphere.  There, just like in the old cloud chambers used to detect particles coming out of particle accelerators, those cosmic rays increase cloud formation acting to cool the Earth.

Svensmark's hypothesis was first demonstrated in the laboratory, but measurements of cosmic rays have been going on for much of the space age.  Cosmic rays have been increasing for the last four years, coinciding with cycle 24's extended solar minimum that we're in, exactly as Svensmark's hypothesis predicts.  This plot shows measured cosmic ray flux from cosmic ray monitoring balloons over California and neutrons penetrating the atmosphere to ground level in Oulu, Finland.  The balloon data includes measurement error bars on every data point.


Both ground level and high altitude cosmic ray measurements are up since March of '15. 

If you want to keep your metaphorical eye on the sun Sunday to see if we've surpassed the record, current sunspot numbers can be looked up in a variety of places.  Spaceweather has them (and says today the spotless day count is 267).   I use ham radio sites like QRZ.  Since 267 isn't the number of consecutive days without a sunspot, it's virtually certain that we'll pass the 269 before the end of the year, even if it's not on Sunday.  Today is only the 30th consecutive day without sunspots.

By the way, it's pretty common for people to say that with the solar activity the lowest in over a hundred years, that we could be headed for an ice age.  It's not that simple or straightforward.  Going back to a quote from WUWT
[T]he year 1913 cited earlier for its lack of sunspots on the order of 311 days was a year filled with wild weather extremes including the hottest temperature ever recorded on Earth in Death Valley, CA. For more on the extreme weather of 1913 click here.
Are we headed for another Maunder minimum?  Nothing in this article changes any of those predictions.  The various predictors don't say that - they lean toward another weak cycle like this one, lasting until about 2030, and then a little higher after that.  One predictor, Dr. Valentina Zharkova, is predicting the low lasts another cycle, possibly two, beyond 2030; that would mean these low solar activity levels until 2052.  For my fellow hams, I'd say to work on your lower frequency systems, say 160 to 20m. 

UPDATE: Dec 16 1630 EST:  The record was broken Sunday.  From Spaceweather.com
SUNSPOTS BREAK A SPACE AGE RECORD: Solar Minimum is becoming very deep indeed. Over the weekend, the sun set a Space Age record for spotlessness. So far in 2019, the sun has been without sunspots for more than 270 days, including the last 33 days in a row. Since the Space Age began, no other year has had this many blank suns.
Since the all-time record for spotlessness is 311 days, and there aren't 41 days left in 2019, we won't break it this year.  Deep, long lasting solar minima are a characteristic of weak cycles; as the 2008-'09 minima demonstrated, so it's a possibility that 311 will fall as the record next year. 



6 comments:

  1. About the best I can do here is my 88' wire, with the ends 15' high and the center at 25'. A genuine cloud burner/worm warmer, but it hears really well out to 500 miles or so.

    I suppose I could make one of those short, loaded things for 160, but the ground conductivity here isn't very good, and I'm not laying out 64 radial wires.....

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  2. The sun is billions of years old and has been impacting the earth for the majority of that time. We puny humans have been observing it in a truly scientific fashion for a couple of centuries. This means we really do not have anywhere near enough data to actually make any kind of predictions, assumptions or even half assed guesses about how the suns actions interact with and affects our weather. It's all just rubber chicken voodoo prognostication. We THINK we know what is happening under the surface of the sun but even THAT is not a certainty. The best we can do is continue to accrue data and compare that data to what happens to planetary weather....in a few thousand years we MIGHT be able to actually put 2 and 2 together with some confidence that the answer will indeed be 4. It's not possible to accurately predict the weather ten days out....to say with any certainty what will happen next month, next year or beyond is hubris defined.

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    1. I think Dr. Zharkova is on to something with the solar dynamo model and her Fourier principle component analysis to identify the various cycles going on, but my gripe with her work is that it's based on samples of no more than three solar cycles, so about 33 years. It matches the record of solar activity fairly well, but absolutely couldn't identify very long period cycles that might be more useful to know about.

      With the knowledge that there are multi-decadal oscillations in both the Pacific and Atlantic, I think you could argue that we haven't been measuring accurately enough for long enough to actually measure "climate" (if that even exists). Then work in that when the "corrections" to the data series are taken out, even that amount of climate change disappears.

      It all falls apart.

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    2. If I am reading Dr. Zharkova's papers correctly, her latest models do correlate well with past climate events several thousand years back, and show a GSM upcoming. Another complicating factor is the movement of the sun around the center of gravity of the solar system, which complicates things even more WRT climate. Propagation not so much.

      NOAA's latest prediction is that SC25 will be the same as 24 in magnitude. I'm betting on Zharkova, and Keypounder's prediction is for 25 to be weaker than 24; your advice to work on low bands is good, methinks

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  3. I'm ok with global cooling, but it just won't be the same without sabertooth tigers.

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  4. William Herschel noted (around 1800 AD) that sunspots were inversely correlated with the price of wheat. When there were few sunspots, the price of grain was high (harvests were bad). When there were many sunspots, the price was low (harvests were good). There's 400 years of tracking this, which in my mind is the most significant piece of evidence against the idea that carbon dioxide is the "thermostat" of climate.

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