Dial M for Maunder

Guest essay by David Archibald

The Maunder Minimum was not completely devoid of sunspots, as shown by the following graphic using data from SIDC. Will global warming be attenuated due to our current low solar activity?

In a comment on a previous post, a Mr B. Fagan notes that the authors of the solar physics paper quoted say “As a consequence, the increase of global warming will be slightly attenuated until 2100 A.D. However, the subsequent increase in solar activity will further enhance the global warming.”

He plaintively asks why the conclusion that global warming will overwhelm whatever the Sun might do is ignored.

Well, the reason it is ignored is because all solar physics papers that touch on climate have the same sort of wording, for exactly the same reason. For example, here’s a Usoskin et al. paper in which at the end of the abstract they say “Although the rarity of the current episode of high average sunspot numbers may indicate that the Sun has contributed to the unusual climate change during the twentieth century, we point out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades.” It is like reading Pravda in Soviet times. You ignore the Party line and read between the lines.

The price of getting published in solar physics is abjuring any role for the Sun in climate. Solar physicists will start giving that up over the next couple of years with the sharp step down in temperature that is underway because otherwise they will run reputational risk for ignoring the obvious. In the meantime they stoically bear the humiliation of having to utter these inanities.

What if you are a normal climate scientist, doing the usual modelling and so on, and you want to get the message out about the effects of the cold climate coming? Well, that requires some mental gymnastics. But it has been done. Professor John Kutzbach of the University of Wisconsin shows how. In the CIA climate report of 1974 predicting severe cooling and a return to the climate of the neo-arboreal era (1600-1850), he is mentioned on page 24. Forty years later, Professor Kutzbach is still at the University of Wisconsin and still warning of cooling. In 2010, he was the co-author of a paper which investigated the effect of a 3.1°C temperature decline on plant productivity. The basis of the 3.1°C assumption was the low carbon dioxide levels of the glacial periods.

Saying the magic words “The Sun can’t have caused the warming” is enough to get most solar physicists published. Others have to recant in public if their findings proved to be inconvenient. For example, in 2011 Dr Richard Altrock published a paper in which he said that, based on observations of the green coronal emissions of the Sun, Solar Cycle 24 was 40% slower than the average of the previous two cycles. This would have a significant effect on climate through Friis-Christensen and Lassen theory. That was followed in 2012 by a paper in which he said that some data had been overlooked in the 2011 paper and that Solar Cycle 24 was back to normal. He hasn’t published his diagram again since.

As far as I can tell, the first solar physicists to suggest that we are heading into a Maunder Minimum were Schatten and Tobiska in 2003. From their abstract,” The surprising result of these long-range predictions is a rapid decline in solar activity, starting with cycle #24. If this trend continues, we may see the Sun heading towards a “Maunder” type of solar activity minimum – an extensive period of reduced levels of solar activity.”

Others on their own efforts have subsequently attempted to untangle the solar record and derive a prediction from it. Thus Steinhilber and Beer, and from the tree rings, Libby and Pandolfi and the Finnish foresters. All are pointing down, steeply down from now. By the time of the CIA climate report in 1974, there was still a living memory of the colder years of the early 20th century, and an appreciation that humanity was in a special time of warmth and abundance. Now forty years on, the cold years that preceded the current warmth are not even a distant memory. Most think that this is the new normal.

Dikpati and Hathaway, both of NASA, in 2006 had predictions of Solar Cycle 24 amplitude of 190 and 170 respectively. In their press release, NASA said that,”Dikpati’s prediction is unprecedented.” It was also terribly wrong, possibly unprecedentedly so. Significantly, no solar physicist is now predicting a return to the high levels of activity of the second half of the 20^th century. Schatten and Tobiska’s prediction of a Maunder level of activity stands, is on track, and has no competition. Everyone is well advised to plan accordingly.

David Archibald, a Visiting Fellow at the Institute of World Politics in Washington, D.C., is the author of Twilight of Abundance (Regnery, 2014).