Text and images transcript of the video Plasma Astrophysics #11: Neutrons and Solar-Radio-Flux by Rolf Witzsche 

Plasma Astrophysics #11: Neutrons and Solar-Radio-Flux

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In the past, solar activity was measured in proxy by counting sunspots. A greater numbers of sunspots, comparatively, represents strong solar activity.

This yardstick for measuring solar activity in terms of sunspot numbers has been used for a long time, though the numbers fluctuate dramatically within the 11-year solar cycles. The plotted numbers form a 'peak' at mid-point of the cycle, and a 'valley' between the cycles. Also, the sunspots themselves have been used to identify the day of the transition of one solar cycle to the next.

The boundary between successive cycles occurs in the 'valley' region where the sunspot numbers are low.

In this weak 'valley' region the magnetic-field orientation on the surface of the Sun flips to its opposite polarity. This occurs typically below the 30-degrees latitudes, and complimentary in each of the hemispheres.

The polarity reversal is 'measurable.' It is 'measurable' in the characteristic of the sunspots. The reversal happens in both hemispheres simultaneously, and complementary to each other. We see the established polarity characteristic shown here as black and white pairs, which typically represent pairs of sunspots, connected by plasma loops.

The orientation of the loops indicates the prevailing magnetic polarity orientation. The changing magnetic orientation changes the direction of the loops. This detectable change in magnetic polarity is counted as a signal that a new solar cycle has started.

But what happens when there are no sunspots visible anymore on the Sun, for us to observe, and when the plasma loops are no longer formed that reveal the prevailing magnetic polarity? What do we have left for us to measure the changing solar activity with?

We are getting close to this zero-sunspot stage. For solar cycle 23, we had 817 days without sunspots. Cycle 24 promises to be weaker still, and at the current rate of the weakening in solar dynamics, solar cycle 25 may not produce any sunspots at all. Here the measurement breaks down.

We had been once in such a predicament before, during the Little Ice age in the 1600s when almost no sunspots were visible for 30 years. This period is known as the Maunder Minimum period.

Society had no idea then how close it had come to the breakdown of the interglacial climate, back to full Ice Age glacial conditions.

Humanity had lacked the capacity at the time to look at solar dynamics at the fainter levels below the zero-sunspot threshold, and monitor solar activity in this 'invisible' region. Nor would anyone have cared, because the discovery of the Ice Age cycles lay still far in the future.

The very concept of an Ice Age was unknown in the 1600s. No one could have imagined that ice had covered much of the northern hemisphere, laid down in sheets of ice miles deep. Nor could have have anyone imagined how close we had come to the phase shift to the full Ice Age already in the late 1600s. The data for these facts had been invisible at the time.

Over time, the invisible became visible. It became possible to measure the effects, in proxy, of changing solar activity, by measuring the historic changes in solar cosmic-ray flux that accompanies changes in solar activity. It had been discovered that the changes in solar cosmic-ray flux had generated changing ratios of the radioactive isotope, Berillium-10. Berillium-10 is produced by cosmic-ray collisions with atomic elements in the Earth's atmosphere. These changing ratios of Berillium-10 production in historic time had been preserved in ice.

 By plotting the Beryllium-10 ratios, it became evident that during of the Little Ice Age, when no sunspots had been visible for almost 30 years, solar activity had diminished more extensively than had been imagined. The solar cycles hadn't stopped during this period, but had become extremely weak. With the new yardstick it became possible to measure changes in solar activity below the Zero-Sunspot Boundary. Because a weaker Sun produces larger volumes of cosmic-ray flux, which increases the Berillium-10 production ratio on Earth, we have a powerful proxy discovered that lets us measure solar activity far into the past, way past the time when sunspot numbers were routinely counted.

Unfortunately, the Berillium-10 ratios were only useful in this manner prior to the dawn of nuclear war and nuclear testing, because in the nuclear age new sources for Berillium-10 were created.

This means that we had to regroup once more and search for still another yardstick that represents exclusively solar activity in real time.

The new yardstick became the Neutron Monitor.

In the high-energy interaction of solar cosmic-ray flux with the Earth's atmosphere, showers of neutrons are released into the atmosphere. The density of the resulting neutron-showers can be measured.

The measured neutron flux stands as a real-time proxy for solar cosmic-ray flux. The two are dynamically the same, because one produces the other. This means that when the Sun is weak, the neutron-flux count is high on the Earth, and vise versa.

When one compares the neutron flux ratios with the solar cycles, the weak solar activity during the 'valley' portion between the solar cycles, corresponds with higher ratios of solar cosmic-ray flux, because the Sun is weaker between the cycles. This is reflected in higher ratios of neutron flux.

Of course, this type of measurement works only in real-time, because when neutrons are split-off from an atomic nucleus, by cosmic-ray collisions, the neutrons decay within a few minutes into becoming protons again, from which they were created when the atoms were formed.

The importance of this new proxy for measuring solar activity is becoming evermore critical the deeper we get into the boundary zone to the next Ice Age.

During solar cycle 22, the last of the big warm cycles, solar cosmic-ray flux was as a low level, especially during the peak in solar activity. When the peak ended, between the cycles, and solar activity dropped to lower levels, the cosmic-ray flux had increased correspondingly, and so had the measured neutron flux ratios, while the Earth experienced a period of cooling. The same happened during cycle 23, except that the warming of the Earth was weaker, and the subsequent cooling stronger. During cycle 24, the solar activity was so weak that no significant warming happened at all, while the cooling became stronger still. That's how the Earth gets progressively colder with no end in sight.

By a similar process the Earth became warmer for almost 300 years, following the little Ice Age. We see in Carbon-14 ratios, which is another proxy for solar activity, that solar activity became up-ramped from the 1700s onward.

When we look at the sunspot cycles for this period, we see the peak-portion of the cycles getting progressively warmer. And when we look at the Berillium-10 plot, where the 'peak' portion represents the 'valley' between the cycles, we see the 'valley' portion, which represents the cooling, getting progressive weaker too. Note, the Berillium-10 is inversely plotted. The accumulative result was that the climate on Earth was getting progressively warmer for 300 years.


In modern time the neutron monitor measures in real time what the Berillium-10 ratios had measured in historic time. The measurements tells us that the reverse of global warming is now happening, that the warming effects of the peak portion is getting weaker, and the cooling effect of the 'valley' portion is getting stronger, with the result that the Earth is getting progressively colder.

In the plot of the measured neutron density ratios, a distinct up-trend in the neutron ratios is apparent, which represents the rate of global cooling. The up-trend reflects closely, the weakening trend in solar activity that the Ulysses spacecraft had measured earlier at a rate of 30% per decade.

The first real-time measurement of solar activity in the boundary zone, was measured by NASA's Ulysses spacecraft in terms of the diminishing solar-wind pressure. With its measurements, Ulysses had measured the beginning of the boundary zone in which the solar dynamics are now collapsing.

During the long span of Ulysses' mission that covered essentially the entire cycle 23 from valley to valley, Ulysses had established a benchmark rate-of-collapse of the solar-wind pressure, at 30% per decade. This rate is also reflected in the decaying solar activity in cycle 24, which is the current cycle, and is consequently reflected in the increased neutron density measurements for this period.

This means that the 30% rate of collapse, per decade that Ulysses had measured, continues to be apparent in the measured neutron ratios after the Ulysses mission had ended. It is reasonable to assume that this rate of collapse will continue into the future, and will determine in part the timing of the phase shift to the next Ice Age.

The Neutron Monitor results are important in this respect, as they confirm that the rate of collapse that Ulysses had measured, still continues, almost unchanged. The Neutron Monitor thereby lets us project the Ulysses' measurements far into the future with a reasonable degree of certainty.

The Moscow Neutron Monitor, one of several, lets us look forward in time, past the zero-boundary for the solar-wind, where the solar wind stops flowing.

Another real-time measurement that lets us look past the zero-boundary into the future, is the solar-radio-flux measurement produced by looking at the Sun in the 10.7 cm radio band, with radio telescopes.

A commentary, by one who appears to be aware of what the collapsing solar-radio-flux numbers hint at, wraps it all up rather shockingly. The comment was in essence, 'the Sun is dying; get out of Europe in three years before they close the borders.'

Whether the comment is justified cannot be determined. The radio-flux numbers vary with the solar cycles. High solar activity produces large flux numbers measured by the solar telescopes. Small numbers represent diminished solar activity. The rate of collapse over the last two solar cycles is ominously large. It should be seen as a wake-up call for society to get its act together.

With the Sun being the master of our climate on Earth, the 30% reduction in solar radio-flux foreshadows crop failures in agricultures all over the world.

While the crop failures are still at the beginning stage, and far from being globally critical, they will likely become critical in the near future. When the growing season shrinks, pressured by winter-blizzards in spring, early autumn snows, and desert conditions increasing in the summer, situations will arise when the crops fail to mature or get destroyed by snow before harvest. A great potential exists here for enormous consequences.

The building of large-scale indoors agriculture that the climate cannot affect, may be our only option for writing us a ticket to have a future, versus having none. But who stands in the hustings, mobilizing the world? The hustings are empty. The supporters are few. To break out of this tragedy is the greatest challenge of our time. Still, we must win, because the alternative is unthinkable.

Towards the goal of winning the fight against the world's prevailing smallness in thinking, the four real-time measurements of solar activity - the collapsing solar-wind pressure, the collapsing sunspot numbers, the increasing neutron density, and the collapsing radio-flux - should rouse the world into action. Each of the 4 real-time measurements, tells us the same story, each in its own way. And that single story that combines them all, is that the Earth and humanity are heading towards the 'unthinkable' in the near term, which no-one can survive, unless we join hands, and hearts, and minds across the world and build the World-Bridge infrastructure for living in an Ice Age world.

The combined story of the 4 real-time measurements of the solar collapse process, stands as a valuable aid for us to rouse us into action in order to have a future. Shouldn't four diverse measurements, which all tell the same story, be sufficient to convince us that the story that each one tells is real? Shouldn't the world listen to the warnings and respond with joy that these stories are now being told, and respond to their imperatives that challenge us to become the giants that we inherently are, which challenge us to become more fully human?

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Published by Cygni Communications Ltd. North Vancouver, BC, Canada - (C) in public domain - producer Rolf A. F. Witzsche