Posts Tagged ‘SC24’

Solar Cycle 24 approaches minimum (the Landscheidt Minimum?)

September 4, 2016

Vencore: The current solar cycle, #24, is the weakest solar cycle in more than a century and it is now heading towards the next solar minimum phase which would be the beginning of solar cycle #25.  The last solar minimum phase lasted from 2007 to 2009 and it was historically weak. …… The current solar cycle is the 24th solar cycle since 1755 when extensive recording of solar sunspot activity began.  Solar cycle 24 is currently on pace to be the weakest sunspot cycle with the fewest sunspots since cycle 14 peaked in February 1906. Solar cycle 24 continues a recent trend of weakening solar cycles which began with solar cycle 22 that peaked around 1990.

In January this year, sunspot activity was declining sharply with the minimum expected around 2019/2010 (last minimum was in 2008/2009). SC24 maximum was reached in 2014 (the second of two peaks with the first in 2012).

SC24 january 2016 (Hathaway-NASA)

SC24 january 2016 (Hathaway-NASA)

Whether we shall see the coming minimum  (the Landscheidt Minimum) to be like the Dalton Minimum or a Grand Minimum like the Maunder Minimum remains to be seen. It should be clear by the time of the SC25 maximum around 2024/2025 and the next minimum in 2030.

It really is time to acknowledge the Landscheidt Minimum:

Landscheidt also predicted that after the next solar minimum in 2030 the following minimum would occur in 2200.

It is perhaps time to officially name this minimum that is coming as the “Landscheidt Minimum”.

The latest SC 24 plot of sunspot number has been posted by NASA/Hathaway:

SC24 august 2016 (Hathaway-NASA)

SC24 august 2016 (Hathaway-NASA)

We are in for 3 decades of cooling.


Solar Cycle 24 passes maximum? Low sunspot numbers and climate cooling indicated for next two cycles

February 11, 2015

It is not completely certain but it does look like Solar Cycle 24 has just passed its maximum. The maximum was initially expected to be reached in late 2012 and gradually drifted to late 2013. Now it would seem that this may not have occurred till late 2014.  While the minima at the beginnings of SC 23 and 24 seem to have been c. 12 years apart, the maxima are closer to 14 years apart.

SC24 2015 January  From NASA Hathaway

SC24 2015 January From NASA Hathaway

The length of Solar Cycles is thought to be linked to the solar activity to be expected in the following 2 cycles. Periods much longer than the average of 11.2 years seem to lead to decreased subsequent activity, lower sunspot numbers and also lower global temperatures.

Solheim et al predicted lower sunspot activity and cooler times during SC 24. Now it would seem this will also be the prevailing paradigm through SC25 and perhaps even SC26. Another two decades of reduced sunspot activity and a global cooling carried by the ocean cycles would seem to be on the cards.


Relations between the length of a sunspot cycle and the average temperature in the same and the next cycle are calculated for a number of meteorological stations in Norway and in the North Atlantic region. No significant trend is found between the length of a cycle and the average temperature in the same cycle, but a significant negative trend is found between the length of a cycle and the temperature in the next cycle. This provides a tool to predict an average temperature decrease of at least 1.0ºC from solar cycle 23 to solar cycle 24 for the stations and areas analyzed. We find for the Norwegian local stations investigated that 25–56% of the temperature increase the last 150 years may be attributed to the Sun. For 3 North Atlantic stations we get 63–72% solar contribution. This points to the Atlantic currents as reinforcing a solar signal.

They write:

The length of a solar cycle is determined as the time from the appearance of the first spot in a cycle at high solar latitude, to the disappearance of the last spot in the same cycle near the solar equator. However, before the last spot in a cycle disappears, the first spot in the next cycle appears at high latitude, and there is normally a two years overlap. The time of the minimum is defined as the central time of overlap between the two cycles (Waldmeier, 1939), and the length of a cycle can be measured between successive minima or maxima. A recent description of how the time of minimum is calculated is given by NGDC (2011): “When observations permit, a date selected as either a cycle minimum or maximum is based in part on an average of the times extremes are reached in the monthly mean sunspot number, in the smoothed monthly mean sunspot number, and in the monthly mean number of spot groups alone. Two more measures are used at time of sunspot minimum: the number of spotless days and the frequency of occurrence of old and new cycle spot groups.”

It was for a long time thought that the appearance of a solar cycle was a random event, which means that each cycle length and amplitude were independent of the previous. However, Dicke (1978) showed that an internal chronometer has to exist inside the Sun, which after a number of short cycles, reset the cycle length so the average length of 11.2 years is kept. Richards et al. (2009) analyzed the length of cycles 1610–2000 using median trace analyses of the cycle lengths and power spectrum analyses of the O–C residuals of the dates of sunspot maxima and minima. They identified a period of 188±38 years. They also found a correspondence between long cycles and minima of number of spots. Their study suggests that the length of sunspot cycles should increase gradually over the next ~75 years. accompanied by a gradual decrease in the number of sunspots.

An autocorrelation study by Solanki et al. (2002) showed that the length of a solar cycle is a good predictor for the maximum sunspot number in the next cycle, in the sense that short cycles predict high Rmax  and long cycles predict small Rmax. They explain this with the solar dynamo having a memory of the previous cycle’s length.

Assuming a relation between the sunspot number and global temperature, the secular periodic change of SCL may then correlate with the global temperature, and as long as we are on the ascending (or descending) branches of the 188 year period, we may predict a warmer (or cooler) climate.

It was also demonstrated (Friis-Christensen and Lassen, 1992, Hoyt and Schatten, 1993 and Lassen and Friis-Christensen, 1995) that the correlation between SCL and climate probably has been in operation for centuries. A statistical study of 69 tree rings sets, covering more than 594 years, and SCL demonstrated that wider tree-rings (better growth conditions) were associated with shorter sunspot cycles (Zhou and Butler, 1998).

Probability of Maunder-like minimum increases

October 28, 2013

I have been of the opinion for some time now that the current Landscheidt Minimum that we are in has a reasonable probability of reaching Dalton Minimum conditions and even developing into a Maunder-like minimum. The Landscheidt Minimum has yet to be officially named. It seems increasingly probable that we are in for some 20 – 30 years of  global cooling. This has not been the view of the global warming enthusiasts who don’t  much believe in the Sun. But now some heavy-weight opinions are also giving more credence to the possibility of a Maunder-like Minimum. We have currently reached solar maximum in Solar Cycle 24 and SC24 and the coming SC25 are comparable to SC’s 4,5 and 6 which corresponded with the Dalton Minimum. Note that the numbering system for Solar Cycles only starts after the Maunder Minimum.

Paul Hudson has been talking to Professor Mike Lockwood:

It’s known by climatologists as the ‘Little Ice Age’, a period in the 1600s when harsh winters across the UK and Europe were often severe. The severe cold went hand in hand with an exceptionally inactive sun, and was called the Maunder solar minimum. 

Now a leading scientist from Reading University has told me that the current rate of decline in solar activity is such that there’s a real risk of seeing a return of such conditions. I’ve been to see Professor Mike Lockwood to take a look at the work he has been conducting into the possible link between solar activity and climate patterns. 

According to Professor Lockwood the late 20th century was a period when the sun was unusually active and a so called ‘grand maximum’ occurred around 1985. Since then the sun has been getting quieter. By looking back at certain isotopes in ice cores, he has been able to determine how active the sun has been over thousands of years. 

Following analysis of the data, Professor Lockwood believes solar activity is now falling more rapidly than at any time in the last 10,000 years. He found 24 different occasions in the last 10,000 years when the sun was in exactly the same state as it is now – and the present decline is faster than any of those 24. Based on his findings he’s raised the risk of a new Maunder minimum from less than 10% just a few years ago to 25-30%. And a repeat of the Dalton solar minimum which occurred in the early 1800s, which also had its fair share of cold winters and poor summers, is, according to him, ‘more likely than not’ to happen. He believes that we are already beginning to see a change in our climate – witness the colder winters and poor summers of recent years – and that over the next few decades there could be a slide to a new Maunder minimum. 

It’s worth stressing that not every winter would be severe; nor would every summer be poor. But harsh winters and unsettled summers would become more frequent. 

Professor Lockwood doesn’t hold back in his description of the potential impacts such a scenario would have in the UK. He says such a change to our climate could have profound implications for energy policy and our transport infrastructure. Although the biggest impact of such solar driven change would be regional, like here in the UK and across Europe, there would be global implications too. ……… 

Recent solar activity (Wikipedia) showing the Maunder and Dalton minima

Solar Cycle 24 double peak now clearly evident

May 9, 2013

Already in March there were signs that this Solar Cycle 24 would exibit a double peak. NASA’s latest sunspot prediction for Solar Cycle 24 as of 1st May 2013 clearly shows that the sunspot activity is into its “double peak for this Cycle. A double peak was also evident in Cycles 22 and 23 and also in Cycles 5 and 14. The levels for SC24 are still going to be the lowest for 100 years and predictions for SC 25 are that they will be even lower still. Most second peaks have been somewhat smaller than the first – though not in SC5 – and seem to add around 6 months to the cycle time.

If this is indeed a double peak then I expect that solar maximum will perhaps be a few months delayed from the NASA prediction of Fall 2013. End 2013 now seems more likely.

SC24 may 2013

The Dalton minimum spanned Solar Cycles 5 and 6 from 1790 to 1820.  The Maunder Minimum from 1645 to 1715 preceded the numbering of Solar Cycles (Solar Cycle 1 started in 1755). The likelihood that SC 24 and 25 may be similar to SC 5 and 6 is growing and so is the likelihood that we will see 2  – 3 decades of global cooling. It is more likely that for the next 20- 30 years this Landscheidt Minimum will resemble the Dalton Minimum period, but if SC25 is a very small cycle then we may even approach the conditions of the Little Ice Age during the Maunder Minimum. Landscheidt’s prediction was that this minimum would last from 2000 to 2060 and the global temperature stand-still for the last 15 years gives greater credence to his forecasts.

NASA: The Sunspot Cycle —

The Maunder Minimum

Early records of sunspots indicate that the Sun went through a period of inactivity in the late 17th century. Very few sunspots were seen on the Sun from about 1645 to 1715 (38 kb JPEG image). Although the observations were not as extensive as in later years, the Sun was in fact well observed during this time and this lack of sunspots is well documented. This period of solar inactivity also corresponds to a climatic period called the “Little Ice Age” when rivers that are normally ice-free froze and snow fields remained year-round at lower altitudes. There is evidence that the Sun has had similar periods of inactivity in the more distant past. The connection between solar activity and terrestrial climate is an area of on-going research.

Double peak in Solar Cycle 24? as in SC14 and in SC5?

March 4, 2013

The NOAA/NASA Solar Cycle Prediction Panel is puzzled. They don’t know if we are reaching solar maximum or whether another little peak could be on its way which would shift solar maximum for SC24 to 2014 from 2013.

And should we compare SC24 with SC14 or should it be SC5?

But SC24 will still show the lowest sunspot activity for 100 years. I note that not only SC14 but even SC5 had a double peak – so my expectation remains that this Landscheidt Minimum may be comparable to the Dalton Minimum – though not perhaps to the Maunder Minimum.

credit Dr. Tony Phillips

credit Dr. Tony Phillips

This Sciencecast video is a good summary of what we don’t know:

Landscheidt’s prediction is that this Minimum will last till 2060 so we can expect low sunspot activity for the next 4 sunspot cycles (till SC28).

Landscheidt’s predicted solar minima

The Sc24 –  SC5 comparison looks like a repeating pattern but it would be wrong to assume that the Sun cares about this and it will surely continue to keep us perplexed as it does its own thing.

SC24 compared to SC5

The Big Picture is persuasive – even if we don’t really know what the sun is upto and even less about how the Earth dances to the Sun’s music.

Recent solar activity (Wikipedia) showing the Maunder and Dalton minima


Solar cycles and the Landscheidt minimum

Theodor landscheidt: Sun-Earth-Man and the Kepler ratios

Major Drop In Solar Activity Predicted: Landscheidt Minimum is upon us and a mini-ice age is imminent

June 15, 2011

The stunning announcement made at the annual meeting of the American Astronomical Society exceeded the expectations from the advance publicity!

The results of new studies were announced today (June 14) at the annual meeting of the solar physics division of the American Astronomical Society, which is being held this week at New Mexico State University in Las Cruces. 

The results of three separate studies seem to show that even as the current sunspot cycle (SC24) moves toward the solar maximum, the sun could be heading into a more-dormant period, with activity during the next 11-year sunspot cycle (SC25) greatly reduced or even eliminated.

The indicators have been  growing for some time that we are in for a a new solar minimum – the Landscheidt minimum – which could be similar to the Dalton Minimum and may even approach the Maunder Minimum. This could mean a cooling period for the earth of 20 – 30 years or for as long as 60 – 70 years. In any event the signs will be unambiguous and inescapable within a decade.

It is reasonable to assume that climatic conditions over the next 20 – 30 years will resemble those prevailing between 1790 and 1820. But SC24 has a way to go yet and it could be that solar activity for SC24 and 25 will be even lower than during the Dalton minimum and perhaps closer to the Spörer minimum but perhaps not as deep as the Maunder minimum.

But in either case the solar activity to come following the Modern maximum may well resemble the 500 years of decline in solar activity which followed the Medieval maximum.

Solar activity events recorded in radiocarbon. Present period is on left. Values since 1950 not shown: Wikipedia

The three papers are: 

  1. “Large-Scale Zonal Flows During the Solar Minimum — Where Is Cycle 25?” by Frank Hill, R. Howe, R. Komm, J. Christensen-Dalsgaard, T.P. Larson, J. Schou & M. J. Thompson.
  2. “A Decade of Diminishing Sunspot Vigor” by W. C. Livingston, M. Penn & L. Svalgard.
  3. “Whither Goes Cycle 24? A View from the Fe XIV Corona” by R. C. Altrock.

 Spacedaily reports:

Major Drop In Solar Activity Predicted

As the current sunspot cycle, Cycle 24, begins to ramp up toward maximum, independent studies of the solar interior, visible surface, and the corona indicate that the next 11-year solar sunspot cycle, Cycle 25, will be greatly reduced or may not happen at all.

“This is highly unusual and unexpected,” Dr. Frank Hill, associate director of the NSO’s Solar Synoptic Network, said of the results. “But the fact that three completely different views of the Sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation.”

Hill is the lead author on one of three papers on these results being presented this week. Using data from the Global Oscillation Network Group (GONG) of six observing stations around the world, the team translates surface pulsations caused by sound reverberating through the Sun into models of the internal structure.

One of their discoveries is an east-west zonal wind flow inside the Sun, called the torsional oscillation, which starts at mid-latitudes and migrates towards the equator. The latitude of this wind stream matches the new spot formation in each cycle, and successfully predicted the late onset of the current Cycle 24.

“We expected to see the start of the zonal flow for Cycle 25 by now,” Hill explained, “but we see no sign of it. This indicates that the start of Cycle 25 may be delayed to 2021 or 2022, or may not happen at all.”

In the second paper, Matt Penn and William Livingston see a long-term weakening trend in the strength of sunspots, and predict that by Cycle 25 magnetic fields erupting on the Sun will be so weak that few if any sunspots will be formed. Spots are formed when intense magnetic flux tubes erupt from the interior and keep cooled gas from circulating back to the interior.

For typical sunspots this magnetism has a strength of 2,500 to 3,500 gauss (Earth’s magnetic field is less than 1 gauss at the surface); the field must reach at least 1,500 gauss to form a dark spot.

Using more than 13 years of sunspot data collected at the McMath-Pierce Telescope at Kitt Peak in Arizona, Penn and Livingston observed that the average field strength declined about 50 gauss per year during Cycle 23 and now in Cycle 24.

They also observed that spot temperatures have risen exactly as expected for such changes in the magnetic field. If the trend continues, the field strength will drop below the 1,500 gauss threshold and spots will largely disappear as the magnetic field is no longer strong enough to overcome convective forces on the solar surface.

Moving outward, Richard Altrock, manager of the Air Force’s coronal research program at NSO’s Sunspot, NM, facilities has observed a slowing of the “rush to the poles,” the rapid poleward march of magnetic activity observed in the Sun’s faint corona. Altrock used four decades of observations with NSO’s 40-cm (16-inch) coronagraphic telescope at Sunspot.

“A key thing to understand is that those wonderful, delicate coronal features are actually powerful, robust magnetic structures rooted in the interior of the Sun,” Altrock explained. “Changes we see in the corona reflect changes deep inside the Sun.”

Altrock used a photometer to map iron heated to 2 million degrees C (3.6 million F). Stripped of half of its electrons, it is easily concentrated by magnetism rising from the Sun. In a well-known pattern, new solar activity emerges first at about 70 degrees latitude at the start of a cycle, then towards the equator as the cycle ages. At the same time, the new magnetic fields push remnants of the older cycle as far as 85 degrees poleward.

“In cycles 21 through 23, solar maximum occurred when this rush appeared at an average latitude of 76 degrees,” Altrock said.

“Cycle 24 started out late and slow and may not be strong enough to create a rush to the poles, indicating we’ll see a very weak solar maximum in 2013, if at all. If the rush to the poles fails to complete, this creates a tremendous dilemma for the theorists, as it would mean that Cycle 23’s magnetic field will not completely disappear from the polar regions (the rush to the poles accomplishes this feat). No one knows what the Sun will do in that case.”

All three of these lines of research to point to the familiar sunspot cycle shutting down for a while. “If we are right,” Hill concluded, “this could be the last solar maximum we’ll see for a few decades. That would affect everything from space exploration to Earth’s climate.”

That last may be the understatement of the century!!!

A photo of a sunspot taken in May 2010, with Earth shown to scale. The image has been colorized for  aesthetic reasons. This image with 0.1 arcsecond resolution from the Swedish 1-m Solar  Telescope represents the limit of what is currently possible in te

A photo of a sunspot taken in May 2010, with Earth shown to scale.This image with 0.1 arcsecond resolution from the Swedish 1-m Solar Telescope represents the limit of what is currently possible in terms of spatial resolution. CREDIT: The Royal Swedish Academy of Sciences, V.M.J. Henriques (sunspot), NASA Apollo 17 (Earth)

An active Sunday for the Sun

February 14, 2011

An unusually active Sunday for the Sun yesterday mainly from the very large sunspot 1158 with magnetic flux values not seen since 2006.


Solar Flares: Mutiple Solar flares took place around Sprawling Sunspot 1158 on Sunday, including an M6.6 Flare which was the 2nd largest of Cycle 24 thus far.  ….. . There will continue to be a chance for M-Class flares and NOAA also lists a 5% chance for an X-Class event.

Solar Flux 107: For the first time in Cycle 24, the official daily solar flux number measured in Penticton, BC closed above 100. The solar flux of 107 is the highest since September 2005. The last time the solar flux finished above 100 was in December 2006.

Solar Update: Huge sunspot 1158 which is located in the southern hemisphere will continue to be a threat for strong solar flares. Elsewhere, Sunspot 1157 which is in the northern hemisphere showed growth late on Sunday and Sunspot 1160 which rotated into view on the eastern limb has sprouted a few new spots as well. The M6.6 Solar Flare did cause a Radio Blackout on HF which was short lived.

Sunspots (Early Monday): image

NOAA forecast:

Solar Activity Forecast: Solar activity is expected to be low to moderate with a chance for a major x-ray event for days one thru three (14-16 February). Region 1158 continued growth and recent major flare make this region the most likely source for a major event. There is a slight chance for C-class activity from Region 1157 and Region 1159.

Geophysical Activity Forecast: The geomagnetic field is expected to be predominately quiet on day one (14 February). Quiet to unsettled with a chance for active conditions are expected on days two and three (15-16 February), due to a recurrent coronal hole high speed stream becoming geoeffective.

NASA reduces forecast for Solar Cycle 24 again

January 19, 2011

In December NASA had reduced its forecasts for SC24 to a peak sunspot number of 64 being reached in June 2013. Now less than two months later, the latest forecast has been reduced again to a peak sunspot number of 59 to be reached in June / July 2013.

We find a starting time of May 2008 with minimum occurring in December 2008 and maximum of about 59 in June/July of 2013.

NASA SC24 forecast - January 2011: image NASA

At these levels the current Landscheidt minimum is comparable to SC5 and SC6 – the Dalton Minimum of 1790 to 1830 – where peak sunspot numbers were just over 50. (The earlier Maunder Minimum – 1645 to 1715- was before the modern period of sunspot number measurement and nominally was a period with no significant sunspots – presumably at sunspot numbers of less than 20 in today’s measurement values).

From my previous post:

It is not inconceivable that the SC24 will not peak till early 2014 and will only achieve peak sunspot numbers around 55. Solar cycle 24 could well have a length of 150+ months instead of the nominal 132 months.

The development of the NASA predictions are in the table below:

NASA Forecasts for SC24

Date of


Expected date

of peak

Expected peak

sunspot number

March 2006 June 2010 168
October 2008 March 2012 137
January 2009 June 2012 104
January 2010 June 2013 90
December 2010 June 2013 64
January 2011 June / July 2013 59


Landscheidt minimum is here — a new Dalton is indicated

December 21, 2010
SDO Sunspot

Spotless Sun

All the indicators are that the Landscheidt minimum is here and that this is going to be close to a Dalton minimum.

2010/12/20 8:00  Five Days in a row spotless is achieved 12 months after solar cycle 24 began it’s ramp up.

A Dalton Minimum Repeat is Shaping Up

The Dalton Minimum was a period of low solar activity, named after the English meteorologist John Dalton, lasting from about 1790 to 1830. Like the Maunder Minimum and Spörer Minimum, the Dalton Minimum coincided with a period of lower-than-average global temperatures. The Oberlach Station in Germany, for example, experienced a 2.0°C decline over 20 years. The Year Without a Summer, in 1816, also occurred during the Dalton Minimum. Solar cycles 5 and 6, as shown below, were greatly reduced in amplitude.

Sunspot number till December 7th

To compare solar cycles we can also use the F10.7 radio flux values that have been recorded since 1947 in Canada. Solar cycle 20 was a weak cycle which is currently looking strong against solar cycle 24. Data is taken from the AU adjusted monthly average values.

%d bloggers like this: