Astronomy

Why is the 11 yr sunspot cycle less predictable recently?

Why is the 11 yr sunspot cycle less predictable recently?



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I quoted from a similar question on solar minima and maxima. "… I guess the jury is still out, but this is quite "fringe" material. The solar cycle is certainly thought to be a product of the dynamo mechanism that produces the magnetic field." So has something changed in the dynamo mechanism?


The solar cycle is no less predictable than it has ever been.

The sun shows a roughly 11 year cycle of activity, but the activity and length in each cycle is also variable and shows trends, but no apparent periodicty


CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=969067

The graph shows 400 years of solar activity. The 11 year cycle is clear, and you can also see some trends in the longer term. The longer term trends don't follow a simple pattern.

So the pattern of solar activity is just as predictable or unpredictable as it has ever been. There is a cycle of 11 years, but what is less clear from the graph is that the some of these cycles are a little longer and some are a little shorter than 11 years. There are longer-term trends that are non-periodic. The causes of the cycle are the periodic relaxations and reversals of the sun's magnetic field. The causes of the longer-term variations are not well understood, and consequently not easy to predict.

There is some evidence of longer-term patterns that are indirectly observable in, for example, variations in the production of Carbon 14 in the atmosphere. There are proposals for periodicities of 210, 2400 and 6000 years.

We can say, with reasonable confidence that the next solar maximum will be in 2025. We expect that the intensity will be similar to the last peak with sunspot numbers at about 100 (based mainly on the observation that there isn't very large swings between one peak and the next). But it could reasonably be between 50 and 150. We would expect there to be peaks in 2036 and 2047, but we have little confidence in how active these future peaks might be, and we are not that confident in the timing.

The cause must be "something in the dynamo mechanism", but such variation is normal for our sun, it seems.


Sunspot cycle

The phase of the sunspot cycle also determines the mean heliographic latitude of all groups. At minimum the first groups of the new cycle appear at 넰�°. Thereafter the latitude range moves progressively toward the equator, until by the next minimum the mean latitude is around ଗ°. Then, while the equatorial groups are petering out, those of the next cycle begin to appear in their characteristic higher latitudes. This latitudinal progression is known as Spörer's law . At any one time there may be a considerable spread in latitude, but groups are seldom seen farther than 35° or closer than 5° from the equator. The butterfly diagram is a graphical representation of Spörer's law obtained by plotting the mean heliographic latitude of individual groups against time (see graph). Its appearance has been likened to successive pairs of butterfly wings, hence the name.

The underlying cause of the sunspot cycle is thought to be the interplay between a large-scale relatively weak poloidal magnetic field beneath the photosphere, differential rotation, and convection. The poloidal field, which is constrained to move with the ionized solar material, becomes increasingly distorted by differential rotation until an intense toroidal field is produced. The strength of this field is further enhanced by the perturbing effect of convection, which twists the field lines into ropelike configurations that may penetrate through the surface to form sunspots. This will occur first in intermediate latitudes, where the field's rate of shearing is greatest, and thereafter in increasingly low latitudes.

The inclination to the equator of the fields of opposite polarity associated with the p - and f -spots is such that they may drift apart in both longitude and latitude, as a result of differential rotation and the cyclonic rotation of individual supergranular cells (see supergranulation). The latitudinal drift is responsible for an accumulation in the polar regions of magnetic flux of the same polarity as the f -spots in the respective hemispheres. Thus the intense (0.2𠄰.4 tesla) localized fields of sunspots are gradually dispersed to form weak (1𠄲 × 10 𠄴 tesla) polar fields, which reverse polarity (not necessarily synchronously) around sunspot maximum. When this happens differential rotation no longer intensifies the subphotospheric toroidal field but rather weakens it and reestablishes a poloidal field of opposite direction to its predecessor.

The sunspot cycle may therefore be regarded (if this model is correct) as a relaxation process that is continually repeating itself. There is reason to believe, however, that at least some of the features of recent cycles may be transitory. In particular, a prolonged minimum, termed the Maunder minimum, from about 1645 to 1715, suggests that there is more than one circulatory mode available to the solar dynamo.

Sunspots are the most obvious but by no means the only manifestation of solar activity to undergo a cyclical change over a period of around 11 years. It is therefore proper to restrict the use of the term sunspot cycle to consideration of the fluctuation of the number of sunspots and to use the more general term solar cycle when considering the variation in the level of solar activity as a whole.


New sunspot cycle could be one of the strongest on record, new research predicts

Credit: Unsplash/CC0 Public Domain

In direct contradiction to the official forecast, a team of scientists led by the National Center for Atmospheric Research (NCAR) is predicting that the Sunspot Cycle that started this fall could be one of the strongest since record-keeping began.

In a new article published in Solar Physics, the research team predicts that Sunspot Cycle 25 will peak with a maximum sunspot number somewhere between approximately 210 and 260, which would put the new cycle in the company of the top few ever observed.

The cycle that just ended, Sunspot Cycle 24, peaked with a sunspot number of 116, and the consensus forecast from a panel of experts convened by the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA) is predicting that Sunspot Cycle 25 will be similarly weak. The panel predicts a peak sunspot number of 115.

If the new NCAR-led forecast is borne out, it would lend support to the research team's unorthodox theory—detailed in a series of papers published over the last decade—that the Sun has overlapping 22-year magnetic cycles that interact to produce the well-known, approximately 11-year sunspot cycle as a byproduct. The 22-year cycles repeat like clockwork and could be a key to finally making accurate predictions of the timing and nature of sunspot cycles, as well as many of the effects they produce, according to the study's authors.

"Scientists have struggled to predict both the length and the strength of sunspot cycles because we lack a fundamental understanding of the mechanism that drives the cycle," said NCAR Deputy Director Scott McIntosh, a solar physicist who led the study. "If our forecast proves correct, we will have evidence that our framework for understanding the Sun's internal magnetic machine is on the right path.

The new research was supported by the National Science Foundation, which is NCAR's sponsor, and NASA's Living With a Star Program.

Sunspot Cycle 25 starts with a bang what will follow?

In McIntosh's previous work, he and his colleagues sketched the outline of a 22-year extended solar cycle using observations of coronal bright points, ephemeral flickers of extreme ultraviolet light in the solar atmosphere. These bright points can be seen marching from the Sun's high latitudes to the equator over about 20 years. As they cross the mid-latitudes, the bright points coincide with the emergence of sunspot activity.

LEFT: Oppositely charged magnetic bands, represented in red and blue, march toward the equator over a 22-year period. When they meet at the equator, they annihilate one another. RIGHT: The top animation shows the total sunspot number (black) and the contributions from the north (red) and south (blue) hemispheres. The bottom shows the location of the spots. Credit: Scott McIntosh

McIntosh believes the bright points mark the travel of magnetic field bands, which wrap around the Sun. When the bands from the northern and southern hemispheres—which have oppositely charged magnetic fields—meet at the equator, they mutually annihilate one another leading to a "terminator" event. These terminators are crucial markers on the Sun's 22-year clock, McIntosh says, because they flag the end of a magnetic cycle, along with its corresponding sunspot cycle—and act as a trigger for the following magnetic cycle to begin.

While one set of oppositely charged bands is about halfway through its migration toward the equatorial meetup, a second set appears at high latitudes and begins its own migration. While these bands appear at high latitudes at a relatively consistent rate—every 11 years—they sometimes slow as they cross the mid-latitudes, which appears to weaken the strength of the upcoming solar cycle.

This happens because the slowdown acts to increase the amount of time that the oppositely charged sets of bands overlap and interfere with one another inside the Sun. The slow-down extends the current solar cycle by pushing the terminator event out in time. Shifting the terminator out in time has the effect of eating away at the spot productivity of the next cycle.

"When we look back over the 270-year long observational record of terminator events, we see that the longer the time between terminators, the weaker the next cycle," said study co-author Bob Leamon, a researcher at the University of Maryland Baltimore County. "And, conversely, the shorter the time between terminators, the stronger the next solar cycle is.

This correlation has been difficult for scientists to see in the past because they have traditionally measured the length of a sunspot cycle from solar minimum to solar minimum, which is defined using an average rather than a precise event. In the new study, the researchers measured from terminator to terminator, which allows for much greater precision.

While terminator events occur approximately every 11 years and mark the beginning and end of the sunspot cycle, the time between terminators can vary by years. For example, Sunspot Cycle 4 began with a terminator in 1786 and ended with a terminator in 1801, an unprecedented 15 years later. The following cycle, 5, was incredibly weak with a peak amplitude of just 82 sunspots. That cycle would become known as the beginning of the "Dalton" Grand Minimum.

Similarly, Sunspot Cycle 23 began in 1998 and did not end until 2011, 13 years later. Sunspot Cycle 24, which is just ending, was quite weak as well, but it was also quite short—just shy of 10 years long—and that's the basis for the new study's bullish prediction that Sunspot Cycle 25 will be strong.

"Once you identify the terminators in the historical records, the pattern becomes obvious," said McIntosh. "A weak Sunspot Cycle 25, as the community is predicting, would be a complete departure from everything that the data has shown us up to this point.


The Sunspot Cycle and How it Affects Ham Radio

There are many factors that can affect our enjoyment of Ham Radio. Some annoyances may be only a few feet away, such as an electric lamp or computer causing RF interference in the shack. But when it comes to headaches for Ham Radio operators, especially HF enthusiasts, the biggest problem (literally) is 92.96 million miles away and is about as easy to negotiate with as your HOA’s rules committee. Of course we’re talking about the sun.

Generally speaking, a dearth of solar activity makes working the bands from 14-28 MHz (20 through 10 meters) and 50 MHz (6 meters) a challenge. The amount of sunspots, and correlating solar activity, decreases or increases according to a predictable 11-year cycle. The presence of sunspots indicates solar activity which affects the ionosphere’s ability to refract radio signals back to Earth. In the simplest terms, fewer sunspots means less solar activity, which leads to a heck of a lot of frustrated Hams.

As of this post, experts are predicting that the number of sunspots will reach its minimum in late 2019 or early 2020. The next cycle is expected to peak between 2023 and 2026.

For more information and daily space weather forecasts, visit the official website of Dr. Tamitha Skov, Space Weather Woman. Dr. Skov spent some time with Hams at DX Engineering’s booth at Dayton Hamvention 2019. Click here for part of her presentation at Hamvention 2019.

One way to endure this low point in solar activity is to shift gears to UHF/VHF operation, including contacting amateur radio satellites—check out this article on the basics of satellite operation. DX Engineering carries a number of HTs and mobile rigs, as well as the new ICOM IC-9700 VHF/UHF/1.2 GHz Transceiver, with special features including smooth satellite operation with normal/reverse tracking and 99 satellite channels.


Will the Sun's current sunspot cycle fizzle or crackle?

Recently, a team of solar scientists announced that they predict the Sun's current magnetic cycle, which just got started about a year ago, will be pretty mild, much like the last one. I wrote about this at the time, because the Sun's behavior can have profound effects on Earth, including damaging satellites, putting astronauts in space in danger, and causing widespread power outages on Earth. The ramifications can be very, very serious.

But hold the presses! Another team of solar astronomers has just published their own study, and, based on their rather unusual hypothesis of the Sun's behavior, predict the current cycle could be very strong, in fact among the strongest ever seen!

Who's right? Well, we'll find out soon enough.

At solar minimum (Dec. 2019, left) nary a spot is seen, while at max (July 2014, right) the Sun’s face is littered with spots. Credit: NASA / SDO / Joy Ng

The Sun goes through a cycle where its magnetic activity grows and weakens on a roughly 11-year period (and in fact the polarity reverses each cycle, with the north and south magnetic poles flipping, so it's really a 22-year cycle). Sunspots are one aspect of this magnetic activity as the cycle goes on and the activity grows, we see more dark sunspots on the Sun's surface. We also see more storm activity like powerful explosive flares and huge coronal mass ejections (CMEs).

It's not well understood why this cycle exists, or what's going on deep inside the Sun to produce it, or why sometimes one cycle is longer or shorter. Mostly we have to extrapolate from what we see on the surface. We also don't know why the strength of the activity changes from cycle to cycle, but sometimes we see fewer sunspots, and sometimes many more.

The past few sunspot cycle number counts, as of 01 December 2020. The last cycle, 24 (arrowed), was weak but short, and scientists predict that short length means Cycle 25 will be strong. Credit: SILSO / Observatory of Belgium

We just came out of Cycle 24, which was fairly weak as they go, with fewer sunspots — it maxed at about 120 seen at the same time. The Sun's face was then blank for a long time until we started seeing spots again in January 2020, and a big one just last week. It's not clear what will happen as we approach the next peak in mid-2025.

That's where the second team of astronomers comes in they disagree with the consensus that activity will be like the last cycle. They base this on past observations of the Sun's complex magnetic behavior, and have posited an odd hypothesis on what's going on with the Sun.

We've known for a while that when a cycle starts up, sunspots tend to form at mid-latitude (around 55° from the Sun's equator) in both of the Sun's hemispheres, and then over time we see them forming closer and closer to the equator. So if you look early in the cycle you see spots around 55° latitude, and a year later they may be down to 50°.

The band in the northern hemisphere has the reverse magnetic polarity from the one in the south. Eventually, when they meet near the equator, they cancel each other out. The scientists call this the termination event, and when that happens the cycle is over.

But here's where it gets complicated. It takes about 19 years for a cycle's bands to get to the equator, and when it's about halfway there another set of bands forms at 55°. They can see this as an increase in solar activity at that latitude, flashes of extreme ultraviolet light that occur above the surface that indicate the presence of deep doughnut-shaped (toroidal) bands of magnetic fields deep beneath the surface.

Sometimes, the migration of these bands down through the mid-latitudes slows. It's not clear why. But the scientists posit that this slowdown allows the bands meeting at the equator to interact for longer periods. This tends to make the solar minimum (when magnetic activity is weak and there are few to no spots) last longer, but they noticed over their observations that it also means the next cycle is weaker, too, producing fewer sunspots.

Conversely, the faster the bands travel across the Sun's mid-latitudes, the stronger the next cycle is.

A sunspot about the same size as Earth was observed by the Daniel K. Inouye Solar Telescope, revealing details as small as 20 km across. The image is about 16,000 km wide. The colors are shown in orange, red, and brown, but the actual wavelength used was 530 nanometers, in the green part of the spectrum. Credit: NSO/AURA/NSF

Normally, cycles are measured from minimum to minimum, but that's actually rather hard to measure. These termination events are easier to measure, and provide a more concrete basis for cycle lengths. And when done this way, the scientists claim, the correlation between cycle length and the next cycle's activity is more clear, and can be extended all the way back to the first cycles observed in the 18th century.

Looking at the various cycles, the average length is 11 years, but some last longer, and what they found is that the cycle after those were weaker. And when a cycle was shorter, the next cycle was stronger.

The number of sunspots versus the length of the cycle (left) shows the last cycle, 24, was weak but short, lasting just 9.5 years. The number of sunspots per cycle plotted against the length of the previous cycle shows a strong trend, and predicts the current cycle (25) should be quite strong. Credit: McIntosh et al.

Cycle 24, the last cycle, lasted only about 9.5 years according to their new method. That's much less than average, among the shortest cycles seen. Therefore, they predict that Cycle 25, the one we're in now, will be quite strong. They predict it should have about 233 spots, although anything in a range of 204 to 254 is within their uncertainty.

But even at the low end that's nearly twice what the other team predicts for this cycle. So we have a clear differentiation between the two, and that means we'll soon see who's correct. It's rare for two competing hypotheses to be so distinct, so the race is on!

The number of sunspots — a proxy for solar magnetic activity — since 1749, showing the roughly 11–year cycle. Scientists predict our current cycle, 25, may be very strong, among the strongest ever seen. Credit: McIntosh et al.

If they're right, then we can expect a lot of activity from the Sun in the next few years. This is critical. There are hundreds of billions of dollars worth of satellites in orbit around the Earth, and they are at risk from big solar events like flares and CMEs, which can damage or destroy their circuitry. Astronauts on the space station need to take shelter in the deepest part of the station when the Sun gets angry, and in 1989 (during Cycle 23) a big CME caused widespread blackouts in Canada, including in Quebec.


Sunspots/Solar Cycle

Sunspots are dark areas that become apparent at the Sun’s photosphere as a result of intense magnetic flux pushing up from further within the solar interior. Areas along this magnetic flux in the upper photosphere and chromosphere heat up, and usually become visible as faculae and plage – often times termed active regions. This causes cooler (7000 F), less dense and darker areas at the heart of these magnetic fields than in the surrounding photosphere (10,000 F) - seen as sunspots. Active regions associated with sunspot groups are usually visible as bright enhancements in the corona at EUV and X-ray wavelengths. Rapid changes in the magnetic field alignment of sunspot groups’ associated active regions are the most likely sources of significant space weather events such as solar flares, CMEs, radiations storms, and radio bursts.

Sunspots appear in a wide variety of shapes and forms. The darkest area of a sunspot (also the first to be observed) is called the umbrae. As the sunspot matures (becomes more intense), a less dark, outlying area of well-defined fibril-like structure develops around the umbrae - called penumbra. Sunspots can grow from an individual unipolar spot into more organized bipolar spot groups or even evolve into immense, very complex sunspot groups with mixed magnetic polarities throughout the group. The largest sunspot groups can cover large swaths of the Sun’s surface and be many times the size of Earth.

Sunspot groups that are clearly visible and observed by designated ground-based observatories, are assigned a NOAA/SWPC 4-digit region number to officially record and track the sunspot group as it rotates across the visible solar disk. Sunspot groups are analyzed and characterized based on their size and complexity by SWPC forecasters each day using the modified Zurich classification scale and Mount Wilson magnetic classification system. This daily sunspot analysis and classification is submitted at the end of each UTC-day as the Solar Region Summary report.

Sunspots can change continuously and may last for only a few hours to days or even months for the more intense groups. The total number of sunspots has long been known to vary with an approximately 11-year repetition known as the solar cycle. The peak of sunspot activity is known as solar maximum and the lull is known as solar minimum. Solar cycles started being assigned consecutive numbers. This number assignment began with solar cycle 1 in 1755 and the most recent being cycle 24 – which began in December, 2008 and is now nearing solar minimum. A new solar cycle is considered to have begun when sunspot groups emerge at higher latitudes with the magnetic polarities of the leading spots opposite that of the previous cycle. A plot of sunspot number progression for the previous and current solar cycle, and that compares the observed and smoothed values with the official sunspot number forecast provided by the Solar Cycle Prediction Panel representing NOAA, the International Space Environmental Services (ISES), and NASA is available to view on our SWPC webpage at solar cycle progression.

The official daily and monthly sunspot numbers are determined by the World Data Center – Sunspot Index and Long-term Solar Observations (WDC-SILSO) at the Royal Observatory of Belgium. Generally, sunspot reports from observatories calculate sunspot numbers whereby each sunspot group counts as 10, and every umbra within each spot group is individually considered as 1. Therefore, no sunspots on the visible Sun would be considered as zero while the next possible number can only be 11 or higher.

More detailed information about sunspot number concepts and a thorough perspective about the solar cycle, can be learned by reading the scientific paper: “Revisiting the Sunspot Number, a 400-year perspective on the Solar Cycle” by F. Clette, L. Svalgaard, J. Vaquero, and E. Cliver Space Sci Rev (2014) 186:35-103 DOI 10.1007/s11214-014-0074-2


Solar experts predict the Sun’s activity in Solar Cycle 25 to be below average, similar to Solar Cycle 24

April 5, 2019 - Scientists charged with predicting the Sun&rsquos activity for the next 11-year solar cycle say that it&rsquos likely to be weak, much like the current one. The current solar cycle, Cycle 24, is declining and predicted to reach solar minimum - the period when the Sun is least active - late in 2019 or 2020.

Solar Cycle 25 Prediction Panel experts said Solar Cycle 25 may have a slow start, but is anticipated to peak with solar maximum occurring between 2023 and 2026, and a sunspot range of 95 to 130. This is well below the average number of sunspots, which typically ranges from 140 to 220 sunspots per solar cycle. The panel has high confidence that the coming cycle should break the trend of weakening solar activity seen over the past four cycles.

&ldquoWe expect Solar Cycle 25 will be very similar to Cycle 24: another fairly weak cycle, preceded by a long, deep minimum,&rdquo said panel co-chair Lisa Upton, Ph.D., solar physicist with Space Systems Research Corp. &ldquoThe expectation that Cycle 25 will be comparable in size to Cycle 24 means that the steady decline in solar cycle amplitude, seen from cycles 21-24, has come to an end and that there is no indication that we are currently approaching a Maunder-type minimum in solar activity.&rdquo

The solar cycle prediction gives a rough idea of the frequency of space weather storms of all types, from radio blackouts to geomagnetic storms and solar radiation storms. It is used by many industries to gauge the potential impact of space weather in the coming years. Space weather can affect power grids, critical military, airline, and shipping communications, satellites and Global Positioning System (GPS) signals, and can even threaten astronauts by exposure to harmful radiation doses.

Solar Cycle 24 reached its maximum - the period when the Sun is most active - in April 2014 with a peak average of 82 sunspots. The Sun&rsquos Northern Hemisphere led the sunspot cycle, peaking over two years ahead of the Southern Hemisphere sunspot peak.

Powerful eruption from the surface of the sun captured on May 1, 2013. NASA

Solar cycle forecasting is a new science

While daily weather forecasts are the most widely used type of scientific information in the U.S., solar forecasting is relatively new. Given that the Sun takes 11 years to complete one solar cycle, this is only the fourth time a solar cycle prediction has been issued by U.S. scientists. The first panel convened in 1989 for Cycle 22.

For Solar Cycle 25, the panel hopes for the first time to predict the presence, amplitude, and timing of any differences between the northern and southern hemispheres on the Sun, known as Hemispheric Asymmetry. Later this year, the Panel will release an official Sunspot Number curve which shows the predicted number of sunspots during any given year and any expected asymmetry. The panel will also look into the possibility of providing a Solar Flare Probability Forecast.

&ldquoWhile we are not predicting a particularly active Solar Cycle 25, violent eruptions from the sun can occur at any time,&rdquo said Doug Biesecker, Ph.D., panel co-chair and a solar physicist at NOAA&rsquos Space Weather Prediction Center.

An example of this occurred on July 23, 2012 when a powerful coronal mass ejection (CME) eruption missed the Earth but enveloped NASA&rsquos STEREO-A satellite. A 2013 study estimated that the U.S. would have suffered between $600 billion and $2.6 trillion in damages, particularly to electrical infrastructure, such as power grid, if this CME had been directed toward Earth. The strength of the 2012 eruption was comparable to the famous 1859 Carrington event that caused widespread damage to telegraph stations around the world and produced aurora displays as far south as the Caribbean.

Forecaster monitors space weather at NOAA&rsquos Space Weather Prediction Center

The Solar Cycle Prediction Panel forecasts the number of sunspots expected for solar maximum, along with the timing of the peak and minimum solar activity levels for the cycle. It is comprised of scientists representing NOAA, NASA, the International Space Environment Services, and other U.S. and international scientists. The outlook was presented on April 5 at the 2019 NOAA Space Weather Workshop in Boulder, Colo.

For the latest space weather forecast, visit https://www.swpc.noaa.gov/

For more information, please contact NOAA Communications Theo Stein, 303-497-0163 and Maureen O&rsquoLeary, 301-427-9000


AI used to predict the next sunspot cycles: low solar activity until 2050

The Sun painted by a machine-learning algorithm in the style of Van Gogh’s Starry Night

Four years ago I did an analysis based on the work of other as well as my own fit to sunspot counts over the past four hundred years. That resulted in an estimate of an extremely cold period for the earth by the year 2030 resulting from the development of a Grand Solar Minimum in sunspot number.

The Sun has just come out of sunspot cycle 24 and is now headed into cycle 25. The earth global temperatures all depend on how strong that next cycle is. NASA has predicted a very weak cycle with a total of less than 50 sunspots.

As I mentioned in a recent post the earth’s global temperatures are headed down. Around the world we are getting reports of unusually cold periods for this time of year. Western Australia just experienced the coldest week on record for May in the past 60 years. We can expect the downward trend to accelerate over the coming months and years as the Sun continues its relative shutdown.

The Solar Cycle we’re entering now (number 25) is forecast to be very similar to the historically weak cycle just past (number 24), but it is expected to be just a stop-over on the sun’s descent into its next full-blown Grand Solar Minimum.

By many accounts, there will not be much of a Solar Cycle 26 to speak of. That will mean extremely cold weather globally for the next few decades, a mini ice age.

The COLD TIMES are returning, the mid-latitudes are REFREEZING, in line with the great conjunction, historically low solar activity, cloud-nucleating Cosmic Rays, and a meridional jet stream flow (among other forcings).

Both NOAA and NASA appear to agree, if you read between the lines, with NOAA saying we’re entering a ‘full-blown’ Grand Solar Minimum in the late-2020s, and NASA seeing this upcoming solar cycle (25) as “the weakest of the past 200 years”, with the agency correlating previous solar shutdowns to prolonged periods of global cooling here.

Furthermore, we can’t ignore the slew of new scientific papers stating the immense impact The Beaufort Gyre could have on the Gulf Stream, and therefore the climate overall.

SCIENTIST USE AI TO PREDICT SUNSPOT CYCLES: For the first time, scientists have used artificial intelligence not only to predict sunspots but also to correct the incomplete record of past sunspot activity.

A new paper just published in Advances in Space Researchby Dr Victor Velasco Herrera, a theoretical physicist at the National Autonomous University of Mexico, Dr Willie Soon, an award-winning solar astrophysicist at the Harvard-Smithsonian Center for Astrophysics, and Professor David Legates, a climatologist at the University of Delaware and former director of the U.S. Global Change Research Program, predicts that the new 11-year solar cycle that has recently begun will show near-record low sunspot activity that will last until mid-century.

Sunspots matter

When there are many sunspots and the Sun is active, there is a danger that a strong solar ejection directed towards the Earth could damage or even destroy the thousands of satellites on which the world depends for everything from radio, telephone, television and internet communications to monitoring the climate and observing the farthest reaches of the universe.

Worse, a really strong solar storm could damage the largely unshielded terrestrial electricity grid. Most power lines and transformers are above ground and thus acutely vulnerable. Solar panels, too, could have their lives shortened by intense solar radiation.

The three scientists taught a machine-learning algorithm how to recognize underlying patterns and cycles in the past 320 years’ sunspot record. The algorithm then discovered a hitherto-unnoticed interaction between the 5.5-year solar half-cycles (blue) and the 120-year Gleissberg double cycles (red dotted lines) which allowed it to confirm the earlier predictions of a quiet half-century to come – predictions which are now shared by solar physicists. See graph below.

Periods of minimum and maximum solar activity from 1700 to 2020 analyzed by machine learning

That interaction between the two periodicities led the algorithm to indicate that from the 1730s to the 1760s, early in the modern sunspot record (the gray band below), sunspots appear to have been under-recorded: as the 120-year cycle approached its maximum amplitude, sunspots should have been more numerous than reported at the time.

The algorithm then predicted the sunspots from 2021 to 2100. It suggests that the current low solar activity is likely to continue until 2050:

The Sun may be quiet for half a century

“Not everyone agrees with our expectation that solar activity will continue to be low for another three solar cycles. A paper in Solar Physics by Dr Scott McIntosh of the U.S. National Center for Atmospheric Research, says the coming solar cycle will be unusually active, with a peak sunspot number of 233, compared with our estimate of less than 100. Place your bets in the Battle of the Solar Cycles!”

“The machine-learning algorithm, with its interesting interplay between the very short 5.5-year cycle and the long 120-year cycle, confirms our results of 10-15 years ago suggesting that the next three or four solar cycles will be comparatively inactive. This is the first time that the twin problems of hindcasting incomplete past records and forecasting the future have been combined in a single analysis.”

“President Trump realized the importance of space weather, and particularly of the Sun, in influencing global climate. It was he who signed the October 2020 ProSwift Act into law to assist in studying and forecasting space weather. Given the history of previous periods of comparative solar activity, the weather may get a little cooler between now and 2050. If we are right, our electricity grids and our satellites should be safe until then.”

You can download the new paper here.

Over the next 30 years we can expect global cooling like not seen since the famous little ice age period called the Maunder Minimum of 1645 to 1715. The Thames river in the UK froze over during the winter, Viking settlers abandoned Greenland, and Norwegian farmers demanded that the Danish king recompense them for lands occupied by advancing glaciers.

The idea of reducing carbon dioxide emissions is so ludicrous considering the need for more crops in the face of rapid cooling which adversely affect agriculture production. More cold fired generation is needed not less. Solar power will be less productive as the Sun’s power diminishes. And probably the wind turbines will freeze solid as was seen in the cold snap Texas experienced a few months back.


The Sun and Sunspots

A typical star, the Sun has a diameter of approximately 865,000 miles (nearly 10 times larger than the diameter of Jupiter) and is composed primarily of hydrogen. The Sun's core is an astonishing 29,000,000 degrees F., while the pressure is about 100 billion times the atmospheric pressure here on Earth. Under these conditions, hydrogen atoms come so close together that they fuse. Right now, about half the amount of hydrogen in the core of the Sun has been fused into helium. This took roughly 4.5 billion years to accomplish. When the hydrogen is exhausted, the Sun's temperature at the surface will begin to cool and the outer layers will expand outward to near the orbit of Mars. The Sun at this point will be a "red giant" and 10,000 times brighter than its present luminosity. After the red giant phase, the Sun will shrink to a white dwarf star (about the size of the Earth) and slowly cool for several billion more years.

Sunspots: One interesting aspect of the Sun is its sunspots. Sunspots are areas where the magnetic field is about 2,500 times stronger than Earth's, much higher than anywhere else on the Sun. Because of the strong magnetic field, the magnetic pressure increases while the surrounding atmospheric pressure decreases. This in turn lowers the temperature relative to its surroundings because the concentrated magnetic field inhibits the flow of hot, new gas from the Sun's interior to the surface.

Sunspots tend to occur in pairs that have magnetic fields pointing in opposite directions. A typical spot consists of a dark region called the umbra, surrounded by a lighter region known as the penumbra. The sunspots appear relatively dark because the surrounding surface of the Sun (the photosphere) is about 10,000 degrees F., while the umbra is about 6,300 degrees F. Sunspots are quite large as an average size is about the same size as the Earth.

Sunspots, Solar Flares, Coronal Mass Ejections and their influence on Earth: Coronal Mass Ejections (shown left) and solar flares are extremely large explosions on the photosphere. In just a few minutes, the flares heat to several million degrees F. and release as much energy as a billion megatons of TNT. They occur near sunspots, usually at the dividing line between areas of oppositely directed magnetic fields. Hot matter called plasma interacts with the magnetic field sending a burst of plasma up and away from the Sun in the form of a flare. Solar flares emit x-rays and magnetic fields which bombard the Earth as geomagnetic storms. If sunspots are active, more solar flares will result creating an increase in geomagnetic storm activity for Earth. Therefore during sunspot maximums, the Earth will see an increase in the Northern and Southern Lights and a possible disruption in radio transmissions and power grids. The storms can even change polarity in satellites which can damage sophisticated electronics. Therefore scientists will often times preposition satellites to a different orientation to protect them from increased solar radiation when a strong solar flare or coronal mass ejection has occurred.

The Solar Cycle: Sunspots increase and decrease through an average cycle of 11 years. Dating back to 1749, we have experienced 23 full solar cycles where the number of sunspots have gone from a minimum, to a maximum and back to the next minimum, through approximate 11 year cycles. We are now well into the 24th cycle. This chart from the NASA/Marshall Space Flight Center shows the sunspot number prediction for solar cycle 24. The NASA/Marshall Space Flight Center also shows the monthly averaged sunspot numbers based on the International Sunspot Number of all solar cycles dating back to 1750. (Daily observations of sunspots began in 1749 at the Zurich, Switzerland observatory.)

One interesting aspect of solar cycles is that the sun went through a period of near zero sunspot activity from about 1645 to 1715 . This period of sunspot minima is called the Maunder Minimum. The "Little Ice Age" occurred over parts of Earth during the Maunder Minimum. So how much does the solar output affect Earth's climate? There is debate within the scientific community how much solar activity can, or does affect Earth's climate. There is research which shows evidence that Earth's climate is sensitive to very weak changes in the Sun's energy output over time frames of 10s and 100s of years. Times of maximum sunspot activity are associated with a very slight increase in the energy output from the sun. Ultraviolet radiation increases dramatically during high sunspot activity, which can have a large effect on the Earth's atmosphere. The converse is true during minimum sunspot activity. But trying to filter the influence of the Sun's energy output and its effect on our climate with the "noise" created by a complex interaction between our atmosphere, land and oceans can be difficult. For example, there is research which shows that the Maunder Minimum not only occurred during a time with a decided lack of sunspot activity, but also coincided with a multi-decade episode of large volcanic eruptions. Large volcanic eruptions are known to hinder incoming solar radiation. Finally, there is also evidence that some of the major ice ages Earth has experienced were caused by Earth being deviated from its average 23.5 degree tilt on its axis. Indeed Earth has tilted anywhere from near 22 degrees to 24.5 degrees on its axis. But overall when examining Earth on a global scale, and over long periods of time, it is certain that the solar energy output does have an affect on Earth's climate. However there will always be a question to the degree of affect due to terrestrial and oceanic interactions on Earth.


Lal, D. & Peters, B. in Kosmische Strahlung II: Handbuch der Physik 551–612 (Springer, 1967).

Herbst, K., Muscheler, R. & Heber, B. The new local interstellar spectra and their influence on the production rates of the cosmogenic radionuclides 10 Be and 14 C. J. Geophys. Res. Space Phys. 122, 23–34 (2017).

Kovaltsov, G. A., Mishev, A. & Usoskin, I. G. A new model of cosmogenic production of radiocarbon 14 C in the atmosphere. Earth Planet. Sci. Lett. 337, 114–120 (2012).

Snowball, I. & Muscheler, R. Palaeomagnetic intensity data: an Achilles heel of solar activity reconstructions. Holocene 17, 851–859 (2007).

Bard, E., Raisbeck, G., Yiou, F. & Jouzel, J. Solar irradiance during the last 1200 years based on cosmogenic nuclides. Tellus B 52, 985–992 (2000).

Muscheler, R. et al. Solar activity during the last 1000 yr inferred from radionuclide records. Quat. Sci. Rev. 26, 82–97 (2007).

Usoskin, I. G. A history of solar activity over millennia. Living Rev. Sol. Phys. 10, 1 (2013).

Beer, J., Vonmoos, M. & Muscheler, R. Solar variability over the past several millennia. Space Sci. Rev. 125, 67–79 (2006).

Steinhilber, F., Beer, J. & Frohlich, C. Total solar irradiance during the Holocene. Geophys. Res. Lett. 36, L19704 (2009).

Miyake, F., Nagaya, K., Masuda, K. & Nakamura, T. A signature of cosmic-ray increase in ad 774–775 from tree rings in Japan. Nature 486, 240–242 (2012).

Miyake, F., Masuda, K. & Nakamura, T. Another rapid event in the carbon-14 content of tree rings. Nat. Commun. 4, 1748 (2013).

Park, J., Southon, J., Fahrni, S., Creasman, P. P. & Mewaldt, R. Relationship between solar acitvity and Δ 14 C in AD 775, AD 994, and 660 BC. Radiocarbon 59, 1147–1156 (2017).

Usoskin, I. G. et al. The AD775 cosmic event revisited: the Sun is to blame. Astron. Astrophys. 552, L3 (2013).

Mekhaldi, F. et al. Multiradionuclide evidence for the solar origin of the cosmic-ray events of AD 774/5 and 993/4. Nat. Commun. 6, 8611 (2015).

Dyer, C., Hands, A., Ryden, K. & Lei, F. Extreme atmospheric radiation environments and single event effects. IEEE Trans. Nucl. Sci. 65, 432–438 (2018).

Bayliss, A. et al. Informing conservation: towards 14 C wiggle-matching of short tree-ring sequences from medieval buildings in England. Radiocarbon 59, 985–1007 (2017).

Stuiver, M. & Braziunas, T. F. Sun, ocean, climate and atmospheric 14 CO2: an evaluation of causal and spectral relationships. Holocene 3, 289–305 (1993).

Eastoe, C. J., Tucek, C. S. & Touchan, R. Δ 14 C and δ 13 C in annual tree-ring samples from sequoiadendron giganteum, AD 998–1510: solar cycles and climate. Radiocarbon 61, 661–680 (2019).

Hong, W. et al. Calibration curve from AD 1250 to AD 1650 by measurements of tree-rings grown on the Korean peninsula. Nucl. Instrum. Methods Phys. Res. Sect. B 294, 435–439 (2013).

Moriya, T. et al. A study of variation of the 11-yr solar cycle before the onset of the Spoerer minimum based on annually measured 14 C content in tree rings. Radiocarbon 61, 1749–1754 (2019).

Menjo, H. et al. Possibility of the detection of past supernova explosion by radiocarbon measurement. In Proc. 29th International Cosmic Ray Conference (eds Sripathi Acharya, B. et al.) 357–360 (TIFR, 2005).

Miyahara, H. et al. Variation of solar activity from the Spoerer to the Maunder minima indicated by radiocarbon content in tree-rings. Adv. Space Res 40, 1060–1063 (2007).

Miyahara, H. et al. Transition of solar cycle length in association with the occurrence of grand solar minima indicated by radiocarbon content in tree-rings. Quat. Geochronol. 3, 208–212 (2008).

Fogtmann-Schulz, A. et al. Variations in solar activity across the Sporer minimum based on radiocarbon in Danish oak. Geophys. Res. Lett. 46, 8617–8623 (2019).

Kudsk, S. G. K. et al. New single-year radiocarbon measurements based on Danish oak covering the periods AD 692–790 and 966–1057. Radiocarbon 62, 969–987 (2019).

Usoskin, I. G. et al. Revisited reference solar proton event of 23 February 1956: assessment of the cosmogenic‐isotope method sensitivity to extreme solar events. J. Geophys. Res. Space Physics 125, e2020JA027921 (2020).

Synal, H. A. & Wacker, L. AMS measurement technique after 30 years: possibilities and limitations of low energy systems. Nucl. Instrum. Methods Phys. Res. Sect. B 268, 701–707 (2010).

Stuiver, M. Solar variability and climatic-change during the current millennium. Nature 286, 868–871 (1980).

Stuiver, M. & Quay, P. D. Atmospheric 14 C changes resulting from fossil-fuel CO2 release and cosmic-ray flux variability. Earth Planet. Sci. Lett. 53, 349–362 (1981).

Keeling, C. D. The Suess effect: 13 C- 14 C interrelations. Environ. Int. 2, 229–300 (1979).

Gleeson, L. J. & Axford, W. I. Solar modulation of galactic cosmic rays. Astrophys. J. 154, 1011–1026 (1968).

Sunspot Index and Long-term Solar Observations (SILSO WDC, 2019) http://www.sidc.be/silso/

Eddy, J. A. The Maunder minimum. Science 192, 1189–1202 (1976).

Usoskin, I. G., Solanki, S. K. & Kovaltsov, G. A. Grand minima of solar activity during the last millennia. Proc. Int. Astron. Union 286, 372–382 (2012).

Brönnimann, S. et al. Last phase of the little ice age forced by volcanic eruptions. Nat. Geosci. 12, 650–656 (2019).

Goosse, H., JoelGuiot, Mann, M. E., Dubinkina, S. & Sallaz-Damaz, Y. The medieval climate anomaly in Europe: comparison of the summer and annual mean signals in two reconstructions and in simulations with data assimilation. Glob. Planet. Change 84–85, 35–47 (2012).

Ganopolski, A. & Rahmstorf, S. Abrupt glacial climate changes due to stochastic resonance. Phys. Rev. Lett. 88, 038501 (2002).

National Research Council Severe Space Weather Events—Understanding Societal and Economic Impacts: A Workshop Report: Extended Summary (National Academies, 2009).

Schrimpf, R. D. & Fleetwood, D. M. Radiation Effects and Soft Errors in Integrated Circuits and Electronic Devices (World Scientific, 2004).

Cuny, H. E. et al. Woody biomass production lags stem-girth increase by over one month in coniferous forests. Nat. Plants 1, 15160 (2015).

Stuiver, M., Kromer, B., Becker, B. & Ferguson, C. W. Radiocarbon age calibration back to 13,300 Years BP and the 14 C age matching of the german oak and united-states bristlecone-pine chronologies. Radiocarbon 28, 969–979 (1986).

Reimer, P. J. et al. IntCal13 and Marine13 radiocarbon age calibration curves 0–50,000 years cal BP. Radiocarbon 55, 1869–1887 (2013).

Sookdeo, A. et al. Quality dating: a well-defined protocol implemented at ETH for high-precision 14 C dates tested on late glacial wood. Radiocarbon https://doi.org/10.1017/RDC.2019.132 (2020).

Němec, M., Wacker, L., Hajdas, I. & Gäggeler, H. Alternative methods for cellulose preparation for AMS measurement. Radiocarbon 52, 1358–1370 (2016).

Welte, C. et al. Towards the limits: analysis of microscale 14 C samples using EA-AMS. Nucl. Instrum. Methods Phys. Res. Sect. B 437, 66–74 (2018).

Wacker, L., Nemec, M. & Bourquin, J. A revolutionary graphitisation system: fully automated, compact and simple. Nucl. Instrum. Methods Phys. Res. Sect. B 268, 931–934 (2010).

Wacker, L., Christl, M. & Synal, H. A. Bats: a new tool for AMS data reduction. Nucl. Instrum. Methods Phys. Res. Sect. B 268, 976–979 (2010).

Reimer, P. J., Brown, T. A. & Reimer, W. R. Discussion: reporting and calibration of post-bomb C data. Radiocarbon 46, 1299–1304 (2004).

Stuiver, M. & Becker, B. High-precision decadal calibration of the radiocarbon time scale, AD 1950–6000 BC. Radiocarbon 35, 35–65 (2016).

Stuiver, M. A note on single-year calibration of the radiocarbon time scale, AD 1510–1954. Radiocarbon 35, 67–72 (1993).

Stuiver, M., Braziunas, T. F., Becker, B. & Kromer, B. Climatic, solar, oceanic, and geomagnetic influences on late-glacial and holocene atmospheric 14 C/ 12 C change. Quat. Res. 35, 1–24 (1991).

Stuiver, M. & Braziunas, T. F. Anthropogenic and solar components of hemispheric 14 C. Geophys. Res. Lett. 25, 329–332 (1998).

Manning, S. W. et al. Fluctuating radiocarbon offsets observed in the southern Levant and implications for archaeological chronology debates. Proc. Natl Acad. Sci. USA 115, 6141–6146 (2018).

Mursula, K., Usoskin, I. G. & Kovaltsov, G. A. Reconstructing the long-term cosmic ray intensity: linear relations do not work. Ann. Geophys. 21, 863–867 (2003).

Owens, M. J., Usoskin, I. & Lockwood, M. Heliospheric modulation of galactic cosmic rays during grand solar minima: past and future variations. Geophys. Res. Lett. 39, L19102 (2012).

Guttler, D. et al. Rapid increase in cosmogenic 14 C in AD 775 measured in New Zealand kauri trees indicates short-lived increase in 14 C production spanning both hemispheres. Earth Planet. Sci. Lett. 411, 290–297 (2015).

Savitzky, A. & Golay, M. J. E. Smoothing and differentiation of data by simplified least squares procedures. Anal. Chem. 36, 1627–1639 (1964).

Boden, T. A. & Andres, R. J. Global, Regional, and National Fossil-Fuel CO2 Emissions (Carbon Dioxide Information Analysis Center, 2016) https://doi.org/10.3334/CDIAC/00001_V2016

Usoskin, I. G., Alanko-Huotari, K., Kovaltsov, G. A. & Mursula, K. Heliospheric modulation of cosmic rays: monthly reconstruction for 1951-2004. J. Geophys. Res. 110, A12108 (2005).

Hellio, G. & Gillet, N. Time-correlation-based regression of the geomagnetic field from archeological and sediment records. Geophys. J. Int. 214, 1585–1607 (2018).


Sunspots at Solar Maximum and Minimum

Our Sun is always too bright to view with the naked eye, but it is far from unchanging. It experiences cycles of magnetic activity. Areas of strong activity manifest as visible spots&mdashsunspots&mdashon the Sun&rsquos surface. The year 2008, however, earned the designation as the Sun&rsquos &ldquoblankest year&rdquo of the space age. Our Sun experienced fewer spots in 2008 than it had since the 1957 launch of Sputnik. As of March 2009, the Sun was continuing its quiet pattern.

These images from the Solar and Heliospheric Observatory (SOHO) spacecraft compare sunspots on the Sun&rsquos surface (top row) and ultraviolet light radiating from the solar atmosphere (bottom row) at the last solar maximum (2000, left column) and at the current solar minimum (2009, right column.) The sunspot images were captured by the Michelson Doppler Imager (MDI) using filtered visible light. On March 18, 2009, the face of the Sun was spotless.

The other set of images, acquired by the Extreme Ultraviolet Imaging Telescope (EIT), shows ultraviolet light radiating from the layer of the atmosphere just above the Sun&rsquos surface. This part of the solar atmosphere is about 60,000 Kelvin&mdasha thousand times hotter than the surface of the Sun itself. On July 19, 2000, the solar atmosphere was pulsating with activity: in addition to several extremely bright (hot) spots around the mid-latitudes, there were also numerous prominences around the edge of the disk. On March 18, 2009, however, our star was relatively subdued.

The long stretch of minimal solar activity in 2008 and early 2009 prompted some questions about whether the Sun&rsquos quiescence was beginning to rival that of the Maunder Minimum in the late seventeenth and early eighteenth centuries. Of the 2008 minimum, solar physicist David Hathaway of the NASA Marshall Space Flight Center says, &ldquoIt&rsquos definitely been an exceptional minimum, but only compared to the past 50 years.&rdquo Citing human observations of the Sun extending back four centuries, he continues, &ldquoIf we go back 100 years, we see that the 1913 minimum was at least as long and as deep as this one.&rdquo So although the minimal activity of the Sun in 2008-2009 is exceptional for the &ldquomodern&rdquo era, it does not yet rival the lowest levels of solar activity that have ever been observed.

Centuries of observations have shown that the number of sunspots waxes and wanes over a roughly 11-year period. Sunspots exhibit other predictable behavior. If you map the location of the spots on the Sun&rsquos surface over the course of a solar cycle, the pattern they make is shaped like a butterfly. The reason for the butterfly pattern is that the first sunspots of each new solar cycle occur mostly at the Sun&rsquos mid-latitudes, but as the solar cycle progresses, the area of maximum sunspot production shifts toward the (solar) equator. Since regular sunspot observations began, astronomers have documented 24 cycles of sunspot activity. The images acquired in July 2000 showed the Sun near the peak of Solar Cycle 23. That cycle waned in late 2007, and Solar Cycle 24 began in early 2008, but showed minimal activity through early 2009.

The small changes in solar irradiance that occur during the solar cycle exert a small influence on Earth&rsquos climate, with periods of intense magnetic activity (the solar maximum) producing slightly higher temperatures, and solar minimum periods such as that seen in 2008 and early 2009 likely to have the opposite effect. Periods of intense magnetic activity on the Sun can spawn severe space weather that damages infrastructure in our high-tech society.

Roughly a million miles away from our planet, the SOHO spacecraft sits between Earth and the Sun, giving us an unobstructed view of the nearest star. Besides the vernal equinox, March 20 marks annual Sun-Earth day, on which NASA celebrates daytime astronomy.

Links

Images courtesy SOHO, the EIT Consortium, and the MDI Team. Caption by Michon Scott with input from David Hathaway, Marshall Space Flight Center, and Joe Gurman, Goddard Space Flight Center.

Our Sun experienced fewer sunspots in 2008 than it had since the 1957 launch of Sputnik. As of Sun-Earth Day on March 20, 2009, the Sun was continuing its quiet pattern.