D'Aleo-Solar Cycle 24 Length and Its Consequences 10 years ago

Recently we posted a story about the USDA redoing their planting zone maps based on the three decades from 1996-2005, As we go through cycles in weather of cooling and warming the planting zones adjust north and south. Here is one response to the USDA analysis from my friend and colleague  Dr Anthony Lupo.

Here below is a two part post by solar expert David Archibald that suggests the USDA's  compasses may be pointing dead wrong on the changes. No one in the policy arena is even considering this possible outcome which would be far more catastrophic  than a 1 degree warming that would extend the growing season and areas where crops can be grown. I pass it along only for your consideration. We will know by the end of the is decade if indeed this is the new threat. Don't let this top 15 warmest winter for the lower 48 fool you. there are examples of unusually warm winters sprinkled in even in the LIA.

If you live near Houston or Washington, David will be in Houston from 20th February to attend North American Prospect Expo in his day job capacity as an oil explorer. He will be in New York from the night of the 24th February to the morning of 28th February, giving a lecture at the Institute of World Politics in Washington that afternoon.

By David Archibald

Solar Cycle 24 is now three years old and predictions of the date of solar maximum have settled upon mid-2013. For example, Jan Janssens has produced this graph predicting the month of maximum in mid-2013, which is 54 months after the Solar Cycle 23/24 minimum in December 2008:


For those of us who wish to predict climate, the most important solar cycle attribute is solar cycle length. Most of the curve-fitting exercises such as NASA’s place the next minimum between 2020 and 2022 (eg). Solar minimum in December 2022 would make Solar Cycle 24 fourteen years long, which in turn would make the climate of the mid-latitudes over Solar Cycle 25 about 1.0°C colder than the climate over Solar Cycle 24.



Curve-fitting leaves a lot to be desired. Even late in the progression of Solar Cycle 23, the curve fitters in NASA had poor predictive ability.

Examination of Altrock’s green corona emissions plot from mid-2011 suggests that a new predictive tool is available to us. The original is available here:


This is my annotated version:


Altrock had observed that solar maximum occurs when the “rush to the poles” reaches 76°. The magnetic poles of the Sun reverse at solar maximum, which is also considered to be the beginning of the new extended solar cycle.

We also observe that solar minimum for the last four minima has occurred when emissions are exhausted at 10°. The latitude of 10° is shown as the red line on the diagramme. Further to that, the last two solar cycles show that the month of minimum can be predicted by drawing a line between solar maximum (the point at which the rush to the poles intersects 76°) and the point of exhaustion at 10°. The bulk of activity is bounded by this line.

Altrock has noted that the “rush to the poles” in Solar Cycle 24 is much weaker and much slower than in previous solar cycles. The line he has drawn intersects 76° in mid-2013, consistent with other predictions of Solar Cycle 24 maximum.

The shape of the emission regions also suggests that Solar Cycle 24 will be quite extended. The blue bounding line from the Solar Cycle 23 maximum intersects 10° latitude in 2026, making Solar Cycle 24 eighteen years long.

That would be an exceptionally long solar cycle. The most recent cycle that neared that length was the seventeen years from the maximum of Solar Cycle 4 to the maximum of Solar Cycle 5. Prior to that, the Maunder Minimum had some very long solar cycles as interpreted from C14 data:


It seems that the first solar cycle of the Maunder Minimum was also eighteen years long.

An eighteen year long Solar Cycle 24 would be very significant in that it would be five and a half years longer that Solar Cycle 23. With the solar cycle length/temperature relationship for the US-Canadian border being 0.7°C for each year of solar cycle length, a further cooling of 3.8°C is in train for next decade. The evolution of Altrock’s green corona emissions diagramme as a predictive tool will be followed with some interest.

Back to the subject of curve-fitting, it may be still too early to call Solar Cycle 24 using that technique. The following graph shows the raw monthly data for sunspot number amplitude for Solar Cycles 5 and 6 (the Dalton Minimum) with Solar Cycle 24 to date aligned on the month of minimum. Solar Cycle 5 took about four years to get going before it had a sudden burst, and then died off over the following ten years. It is still a bit too early to be certain about how Solar Cycle 24 will shape up.


Three wise Norwegians – Jan-Erik Solheim, Kjell Stordahl and Ole Humlum – have just published a paper entitled “The long sunspot cycle 23 predicts a significant temperature decrease in cycle 24”. It is available online here: http://arxiv.org/pdf/1202.1954v1.pdf

The authors have found that Northern Hemisphere temperature changes by 0.21°C per year of solar cycle length. The biggest response found in the temperature series they examined was Svalbard at 1.09°C per year of solar cycle length. The authors also credit me with the discovery of a new branch of science. On page 6 they state.” Archibald (2008) was the first to realize that the length of the previous sunspot cycle (PSCL) has a predictive power for the temperature in the next sunspot cycle, if the raw (unsmoothed) value for the SCL is used.” I have decided to name this new branch of science “solarclimatology”. It is similar to Svensmark’s cosmoclimatology but much more readily quantifiable.

What we use solarclimatology for is to predict future climate. Professor Solheim and his co-authors have done that for Solar Cycle 24 which takes us out to 2026. Using Altrock’s green corona emissions diagram, we can go beyond that to about 2040: http://wattsupwiththat.com/2012/01/08/solar-cycle-24-length-and-its-consequences/

The green corona emissions point to Solar Cycle 24 being 17 years long, and thus 4.5 years longer than Solar Cycle 23. Using the relationship found by Solheim and his co-authors, that means that the 0.63°C decline for the Northern Hemisphere over Solar Cycle 24 will be followed by a further 0.95°C over Solar Cycle 25. That is graphically indicated thusly, using Figure 19 from the Solheim et al paper:



The last time we witnessed temperatures anything like that was in the decade 1690 – 1700. Crop failures caused by cold killed off 10% of the populations of France, Norway and Sweden, 20% of the population of Estonia and one third of the population of Finland.

As noted above, Svalbard’s relationship is 1.09°C per year of solar cycle length. That means that it is headed for a total temperature fall of 8.2°C. The agricultural output of Svalbard and the rest of the island of Spitsbergen won’t be affected though, because there isn’t any. The biggest effect will on some of the World’s most productive agricultural lands. The solar cycle length – temperature relationship for some localities in the northeast US is 0.7°C degrees per year, which is a good proxy for the latitude of the US – Canadian border and thus the North American grain belt. Newman in 1980 found that the Corn Belt shifted 144 km per 1.0°C change in temperature. With the temperature falling 5.2°C, the Corn Belt will shift 750 km south to the Sun Belt, as shown following:


The outlook for Canadian agriculture is somewhat more dire. I expect Canadian agriculture will be reduced to trapping beavers, as in the 17th Century.

The current cold conditions in Europe resulted in more than 300 souls departing this mortal coil, and has discomforted some millions. Solheim and his co-authors note “As seen in figures 6 and 7, the Norwegian and Europe60 average temperatures have already started to decline towards the predicted SC24 values”.


Newman, J. E. (1980). Climate change impacts on the growing season of the North American Corn Belt. Biometeorology, 7 (2), 128-142. Supplement to International Journal of Biometeorology, 24 (December, 1980).