Sublime Support and Ridiculous Rebuttal of Akasofu’s Natural Variation Paper

Back in May, MDPI’s new Journal, Climate, published a paper by Japanese researcher Syun-Ichi Akasofu entitled ‘On the Present Halting of Global Warming’. The paper proposes the idea that the recovery from the little ice age and the 60 year oscillation evident in the data not reproduced by climate models needs subtracting from the temperature history before the effect(if any) of additional atmospheric co2 can be assessed. This enraged several of the new journal’s editorial panel so much that they resigned. The Chief editor provided this reassurance and reasoning:

What we can disclose about the review process of the Akasofu paper, without violating the confidentiality of the review process, is that the manuscript was reviewed by three specialists affiliated to institutes or universities based in Europe and the USA. The reviewers were not from the same institution as the author and they have not co-authored papers with the author in the last five years…

We hope that this opportunity for debate will be taken up by members of the scientific community, and that Climate can facilitate vibrant discussion around environmental climate topics that can often polarize opinion, but are of vital importance for stimulating cutting edge research.

Quite right too. Proper scientific debate is to be preferred to editors flouncing. This kind of histrionic approach to rebuttal is unscientific, as an eminent PhD pointed out:

If a scientist does not agree with the results of a published study, he or she should submit a paper presenting counterarguments backed by data and physical analysis instead of making silly political ‘statements’ such as resigning. This not how real science works.

Indeed. But now, a ‘Rebuttal’ comment from a group of the usual suspects (including the hilarious Dana Nuccitelli and Scott Mandia) has been published at the journal’s website purporting to demonstrate that:

The claim that a two-century linear temperature increase is a recovery from a recent cool period is not supported by the data. Furthermore, this thermal recovery hypothesis is not connected to any physical phenomenon; rather it is a result of a simplistic and incorrect curve-fitting operation.

Lets take a look.

Here’s the abstract of Akasofu’s paper:

The rise in global average temperature over the last century has halted since roughly the year 2000, despite the fact that the release of CO2 into the atmosphere is still increasing. It is suggested here that this interruption has been caused by the suspension of the near linear (+ 0.5 °C/100 years or 0.05 °C/10 years) temperature increase over the last two centuries, due to recovery from the Little Ice Age, by a superposed multi-decadal oscillation of a 0.2 °C amplitude and a 50~60 year period, which reached its positive peak in about the year 2000—a halting similar to those that occurred around 1880 and 1940. Because both the near linear change and the multi-decadal oscillation are likely to be natural changes (the recovery from the Little Ice Age (LIA) and an oscillation related to the Pacific Decadal Oscillation (PDO), respectively), they must be carefully subtracted from temperature data before estimating the effects of CO2.

First thought is that the ‘linear’ recovery from the LIA isn’t really linear, but in the absence of strong supporting evidence for a suitable climate oscillation, Akasofu chose to keep it simple. But we can help him out with a bit of Talkshop hindcasting and prediction skill here. Back in feb 2010 Tim C and I posted an article on replicating Judith Lean’s TSI reconstruction using the underlying sinusoidal oscillations discovered in the data by Tim’s brilliant analysis software. One of the oscillations was at a period of around 426 years, see figure 1.

Figure 1: The long period oscillation found in the Lean reconstructed TSI envelope is 426 years, and phases well with LIA recovery

Other things worth noting in Figure 1 are that the peaking of this long period oscillation around the time of the US dustbowl in the 1930s, along with the near Gleissberg cycle 80yr period, and the the next upturn in the 426yr period won’t occur until around 2150AD. Note also the 80 and 220yr period were at a minimum around 1900, when solar activity was low. The modern solar maximum peaked around 2003 along with the 220 period near the De Vries cycle length. The near 60 year period was already on it’s way down, along with the PDO. As you can see, the next few decades show a steep fall in solar activity.

Now one of the usual suspects who wrote the rebuttal paper, Rasmus Benestad, is the ‘solar expert’ amongst the group, the others knowing exactly SFA about solar variation. No doubt he would try to rubbish the findings of Figure 1 as “simplistic curve fitting” as well. But since the cycle lengths found near to periods found in the 14C data, it’s not so easy to dismiss. A few years ago, Rasmus teamed up with another usual suspect who knows SFA about solar variation, Gavin Schmidt, to write a paper rebutting a paper by Nicola Scafetta. This paper contained a fatal stats error which entirely invalidated it’s content. I posted about this a while back.

The journal in question refused to publish Nicola Scafetta’s comment on this fatally flawed paper, and Nicola lost interest in fighting that decision, as he had more interesting work to do. So the falsified paper still stands, and although Benestad and Schmidt are fully aware of its invalidity, they won’t withdraw the paper. In fact Benestad still cites it in his more recent work, and it is relied on by the new IPCC AR5 report. That’s something we’ll be having a guest post from Nicola Scafetta about soon.