The Importance of Solar Cycles
This article was originally published on the Solar Cycle 25 website on June 28th 2009 and in view of the weakness of cycle 24 it is becoming increasingly relevant.
I have already dealt with the likelihood that the IPCC was in error regarding solar influence in my earlier article which can be found here:
For the purposes of this article I will ignore the Urban Heat Island effect that seems to have contaminated the surface station record as a result of poor recording site management and surrounding development over many years. Suffice it to say that the more recent satellite recordings do confirm a warming of the air until recently, albeit less than suggested by surface records and far less than that anticipated by climate models.
The concern about the human effects on global climate as opposed to local effects is now reaching a crescendo with energy control, pricing and rationing measures being pushed through in many parts of the Western world and especially in the USA and the UK.
Energy costs are critical to modern civilisations and their abilities to advance whilst providing adequately for their citizens, especially the poorest, so anything that significantly affects such costs or indeed energy availability is of the utmost importance.
If the sun is primarily responsible for observed global air temperature changes (even if heavily modulated by ocean behaviour as I contend elsewhere) then we need to know sooner rather than later otherwise a misdiagnosis of the causes of climate change could cause unimaginable disruption and hardship through the imposition of incorrect remedies.
The sun and it’s cycles seem to have undergone a sharp change in behaviour in recent years hence the importance of concentrating specifically on the solar cycles 24 and 25 which taken together are likely to tell us much of what we need to know about climate change and thus the right measures we need to adopt in order to adapt to it. I do not believe we can ever adequately control natural climate swings.
The Basic Phenomenon
The sun varies over a period of approximately 11 years. More accurately the lengths of the cycles we have observed have been between 9.0 and 13.6 years. During the course of each cycle the activity of the sun varies and is best observed from the number of sunspots which waxes and wanes through the cycle. No one knows why.
Furthermore the level of activity varies from cycle to cycle and that level of activity is itself linked to the length of the cycle.
It seems that in terms of the total amount of energy coming from the sun there is only a very small variation due to the changing level of solar activity during a single cycle. Apparently there is a variation from top to bottom of each cycle of only 0.01% of the total. However it may be that the change in length of a cycle creates a bigger difference in average energy delivered during each day, week, month or year of the particular cycle.
The smallness of that variation from peak to trough of a single cycle has caused considerable doubt as to how significant changes in the air temperatures could occur at time scales of up to a century but the net energy delivery effect of a change of length does not appear to have been properly investigated.
My opinion expressed elsewhere is that almost all the temperature changes we observe over periods of less than a century are caused by cyclical changes in the rate of energy emission from the oceans with the solar effect only providing a slow background trend of warming or cooling for several centuries at a time.
The best evidence in support of that proposition of slow long term solar background changes is the gradual and irregular change from Roman Warm period to The Dark Ages to the Mediaeval Warm Period and thence to the Little Ice Age and finally to our recent Modern Maximum. The irregularity of the temperature changes within those main background trends cannot have been anything to do with humanity and can adequately be catered for by varying oceanic effects on multidecadal time scales. I for one am quite sure that exactly the same scenario accounts for all the temperature changes in the air observed during the 20th Century including that of the late 20th Century.
The link between solar cycle length and decadal global temperature changes is obvious throughout all the weather records.
Short fast cycles with many sunspots result in warming. Long slow cycles with fewer sunspots result in cooling. In each case heavily modulated by ocean behaviour on decadal time scales but readily apparent over a century or two.
The mechanism (or, more likely, mechanisms) which explains the clear and obvious link between global air temperaures and solar/oceanic changes has not been ascertained adequately but it isn’t anything to do with CO2.
It is clear that the late 20th Century warming spell matched the duration of the two shortest, fastest solar cycles in the historical record ( 21 and 22) At the same time there was a matching sequence of strong El Nino events. These points should not be lightly dismissed. The cooling fears of the 60’s and early 70’s coincided with slightly weaker (but still historically high) solar cycle 20 and the recent cessation of warming occurred during cycle 23 which has been slightly weaker than the two cycles before it.
The recent cessation of warming from about 2000 and the more recent cooling since 2007 have coincided with the reduction in solar activity between cycles 23 and 24.
On balance the evidence shows that solar and oceanic variations are more likely the cause of recent observations of warming in the air than increasing CO2 in the air but the issue can soon be resolved by observing the global air temperature changes that occur during and after the extended cycle 23 and the probable weak cycle 24.
The ‘Establishment’ View
As regards the background effect of solar changes I find the work of David Archibald very persuasive
However for some reason there is a marked reluctance on the part of the solar and climate establishments to give any weight to that historical evidence and the frequent marked correlations over centuries.
A very well informed solar scientist whom I respect asserts that the correlations are not significant. He holds that view even though periods when the correlation is weak can be adequately explained by oceanic modulation of the background solar signal.
The IPCC continues to deny (does that make them ‘denialists’) that the so called ‘Grand Solar Maximum’ of the late 20th Century had anything to do with the observed warming because from the very high solar cycle 19 to the still high but declining cycle 23 there was a tiny drift downwards in solar activity. They say that just because the global air temperature continued to rise whilst the activity of the sun was coming down from a lengthy historic peak then there can have been no significant contribution from solar input.
In my opinion that is a silly position for the IPCC to take. An electric fire does not immediately stop warming up a room because it is turned down a little. Instead the room keeps warming until the energy leaving the room matches the surplus energy coming from the fire. It might be necessary for the fire to cool a lot before the room stops warming. In the case of Earth the oceans are well capable of continuing to accumulate energy and/or warm the air despite a small reduction in solar energy from a previous peak.
The Current Status of Solar Activity
We are now at the end of solar cycle 23 and just about to start cycle 24.
Against all predictions and projections from those who purport to know what they are talking about, cycle 23 became longer and longer with the activity of cycle 24 failing to increase in accordance with expectations.
As each day passes the ideas of one Timo Niroma become more and more intriguing.
He modestly describes his work as a statistical exercise and declines to be firm about the causative mechanisms but he appears to be on to something.
It is a long and complex work so I reproduce his summary here (with grammar slightly amended) :
“According to my theory about a Jovian effect on sunspots, based on measurements since 1700 and estimates since 1500 (Schove), the Jupiter perihelion and sunspot minimum never coincide and the nearing perihelion in 2011 will slow the rise of the height of the sunspot cycle, as is now happening to the cycle 24.
– The Gleissberg cycle almost reached its lower limit, which is 72 years in 2005.
— In fact this low it has not been since the Maunder minimum.
— So it must go up, the short cycles of the 20th century have created a debt that must be paid.
— This means lower cycles and if the past is a good predictor, colder times on Earth.
The last decent sunspots belonging to cycle 23 appeared in July 2008. From August to September 2008 the Sun hibernated. In October and November 2008 the cycle 24 showed its first decent spots. In December 2008 the Sun again began to hibernate if we count only the sunspots. At the same time there however began a rise (corrected to 1-AU-distance) of the 10.7 cm flux from December 2008. In May/June it seems that the hibernation is over (at least for the time). The slow rise of the cycle 24 may be due to Livingston-Penn phenomenon of the spot’s decreasing magnetism since at least 1990 which may delay the ongoing cycle switch. It seems that the time period from January to April 2009 has all the time been merely a preparation for cycle 24. We just did not in the 20th century get accustomed to seeing so quiet a period.
This prolonged minimum and the delay of the cycle 24 mean that the cycle 24 will be very low, in the range of 30-50. This is at or below the Dalton level. My Jovian cycle paradigm is in accord to the minimum having been in November 2008. The 0.8 year period is here apparent (minimum 3*0.8 years before the Jovian perihelion and the June activity 2*0.8 years before are good indications). I expect the maximum in 2014 or 2015. The length of the cycle 23 will be 12.5 years.
The point is that a length that exceeds 12 years has always led to prolonged grand minimum (1798 Dalton minimum, 1856 Damon minimum). It is not known exactly how long the cycles before Maunder minimum were, but there seems to have been a minimum in 1620. This leads to 25 years for the two cycles 1620-1645 just before Maunder. (i.e. 12.5 years each comparable to 12.5 for cycle 23).
This means a cooling for decades, at least for 30 years, but we cannot be sure we are on a course to a new LIA (Little Ice Age). A low Dalton is probable, but one can’t be sure, there are too many indications of the solar magnetic field having a deep dive. If we put them together with the fact that all relevant cycles are at or near minimum, I wouldn’t be surprised to see the next cycle 25 failing and having a crash leading to a Maunder-type minimum.
(A sidestep: The rise of the CO2 in atmosphere from 0.03 to 0.04 % does not have any meaning in this play where the water vapour is far the greatest player. I am a statistician and this is a statistical study, but a remark for those, who urgently for years have asked me what I think about the physical link: The Earth’s magnetic field is very sensible to variations in the solar magnetic field. This may have far greater effects on Earth than just the aurorae or breakdown of man-made electrical grids. I find the Svensmark theory (2006) of cosmic rays oscillating to the rhythm of the Sun’s magnetic field as the most promising. More cosmic rays leads to more clouds in the lower atmosphere, which cools the Earth. The CERN investigations in 2010 probably will settle the issue.
As I understand it the water vapor is the most forceful greenhouse gas. Although in the beginning a positive feedback when the water vapor changes to clouds the feedback changes to negative thus keeping a balance, where a 0.01% rise (in CO2) can’t have any discernible influence. If the water vapour feedback didn’t, in the end, change to negative, the Earth would eons ago have lost its oceans. There are also indications that the UV spectrum of the solar radiation oscillates many times more than the visible part. A sizable drop in UV plus sizable drop in TSI (Total Solar Irradiation) plus a sizeable drop in the spots’ magnetic power combined with on-going cycle switches with bottom values creates thus an environment where all preconditions for a Maunder Minimum type minimum are set.)“Published by Stephen Wilde July 31, 2013