Science and Technology CommitteeWritten evidence submitted by Professor Anthony Trewavas FRS, FRSE (CLC016)

1.This short paper is written by Professor Anthony Trewavas FRS, FRSE, Academia Europea. It is in response to a request from the Science and Technology committee for information on why the public seem disinclined to go along with its policy on climate change. That assumes its policy is correct, I see a need to be more circumspect. In summary, the following are outlined.

The difference between projection and prediction.

The necessity of scepticism in climate science and the difficulties in testing climate models.

Whether CO2 increase is the driver of climate temperature or is it the reverse?

I conclude that a lack of certainty should lead to removal of legislation.

2. Unless otherwise stated, the climate evidence to which I refer is to be found on and its various subsections on proxies, ice cores, etc. This site provides a scientifically-balanced introduction to climate data.

The Difference between Projection and Prediction

3. That there are problems with the public perception of climate change is not surprising and results from the common confusion between predictions and projections. A prediction is a defined future; instead, a projection is what might happen. It is the difference between certainty and possibility. Unpredictable events, large volcanic eruptions, asteroids can destroy all attempts at prediction as can changes in technology.

4. Hydraulic fracturing is just one instance; its introduction has made nonsense of many predictions of fossil fuel limitations of natural gas resources and also inadvertently reduced USA emissions*. There will be other technological advances; we are a highly creative species.

*[Any scrutiny of the US governments EIA (environmental information administration) would have indicated several centuries worth of technically recoverable reserves of coal, oil or gas].

5. Climate models can only provide projections, they are not predictions. Confusion between these different words has led to many climate models being presented by government, NGO’s and some scientists as predictions. No doubt those scientists, who did so, were well meaning. They admitted sometimes to exaggerating effects to convince the public. But the role of science is to provide unbiased, balanced assessments. If the public are told that climate science predicts continual warming then several very cold winters, leads to rejection of the claim. The complexity of climate renders predictions impracticable and there is need for honesty and transparency about the uncertainties of climate change. What was omitted was that climate models at best only offer probabilities, something it was felt the public would not understand.

The Essence of Science is Scepticism

6. Sceptical assessments form the basis of scientific progress. Models are only as good as the information put into them. Questioning climate models is an essential part of progress on understanding.

7. Those who produced climate models should have been those most vigorous in attacking their own hypotheses and making others aware of their limitations. That is how scientific knowledge expands. Instead as the unfortunate case at the University of East Anglia showed, this group were acting as cheerleaders of their own modelling even to the extent of attempting to damage the credibility of those that questioned what they had published.

8. The term Denier or Denialist to describe sceptics is indicative of the closed mind and a term of abuse for the scientific process. It is reminiscent of Galileo’s problem with the inquisition in the 16th century and politicians of all kinds should have slapped the term down.

9. The last IPCC in 2007 indicated that there were some 20 or so different models, projecting estimates anywhere from 1.5 to 6 C for either 2100 or a doubling of CO2 levels. That in itself should have negated the notion of climate models as predictions. It indicates climatological uncertainty. The variety results from different basic assumptions but given there is only one future, only one model or none can actually prove right.

Can Climate Models be Tested or Refuted.

10. Karl Popper laid down some simple criteria of a scientific enterprise. What is proposed must be capable of being tested or refuted. Whereas normal science is experimental and conforms readily with Popper’s description of easy refutation, climatology is reduced to modelling only and thus suffers inevitable uncertainties because knowledge is incomplete. The extent of ignorance is unknown. The only way a climate model can be refuted is to compare the projections over suitably long periods of time (15–20 years) with actual climate observations. If policy is based on models, as is the case, there is a large inherent risk that after 20 years the policy will have been seen to be wrong because the model was inaccurate. Is this not now beginning to be the case?

11. All the models proposed in the late 90’s and early noughties have so far proved poor predictors of climate temperature variation and I refer to the apparent stasis in temperature from 1998 onwards. A similar period of stasis occurred in the 1940’s and in both cases atmospheric CO2 continued to climb. If this coming year continues, as the previous 12–14 years, then the 95% confidence level around the current common mean projected climate temperature, will have been breached (E. Hawkins. [A breach of the 95% confidence level indicates a probability of less than 1 in 20 and is usually used in all areas of statistics to indicate high significance].When politicians were urged to act by some scientists, none of the climate models generated at this time included a period of stasis. All should have been more circumspect.

12. The apparent stasis indicates that there are aspects to the climate which modellers have not taken into account because they are not understood. Natural variation is one ascribed reason and something studiously ignored 20 years ago when mankind was blamed for any change of climate. I know of no unambiguous way in which natural variation, whatever it is, can ever be distinguished from mankind’s contribution. Even if the climate temperature had varied as models indicated for a decade or more that does not indicate it is correct. Correlations are not proof.

13. The climate temperature can do one of three things; go up, down or stay the same. Given the errors in modelling it seems to me that modellers have a one in three chance of being approximately right. If the projected temperature is increasing slightly faster or slower but similar to the general direction, I get the impression most modellers would consider they were justified in their claims. But even with these three categories, the current set of models have failed because the temperature is, at present, approximately constant so they have failed on a one in three chance.

14. The reaction by some scientists to the apparent stasis has been to state that the temperature of the last 20 years is higher than the previous 20 years and therefore climate models and assumptions are correct. The climate temperature has been rising for the last 150–300 years depending on whose results you look at, so that is hardly a surprising observation. Current models are poor predictors and that creates uncertainty for policy decisions.

15. If climate change is primarily natural, nothing can be done except to adapt. To describe climate change as dangerous is to downgrade our ability to create solutions and is not based on real situations given the enormous complexity and difficulty of predicting any future world situation.

Misleading “Hockey Sticks”.

16. The original “hockey stick” graph of climate change was generated by Professor Michael Mann at Pennsylvania State University. The graph figured strongly in the IPCC 2000, notably on the cover and five times elsewhere in the report but it is an artifice. What was not made clear at the time is that the flat part of the graph is a temperature proxy (dendrochronology) whereas the increasing part that was grafted on to it is actual temperature measurements.

Tree rings are formed by the activities of the dividing cells of the cambium, a kind of inner sheath, that generates new phloem to the inside and new xylem to the outside of the cambium. Tree rings are part of the process of plant development in large woody dicotyledonous angiosperms. Because it is development, the size of the tree ring is determined by everything that affects all aspects of plant development. These are : soil nutrients and structure; light variations; carbon dioxide; competition from other trees; disease; predators; age; rainfall; previous developmental activity as well as temperature. Temperature, for which it supposedly acts as a proxy, is just one contributor amongst many and of course reflects local conditions only. Mann’s “Hockey Stick” failed to register the historical variation of warm medieval period when Greenland was actually green and the little ice age that dominated in the years 1600–1700s. Greenland was abandoned in the late 1400’s as temperatures declined. Tree rings on their own are not a reliable proxy and examination of tree rings from trees from numerous sites indicates inconsistencies. Stable isotope analysis of tree rings may be more useful. Policy was probably influenced by this uncertain information.

The conflict of carbon dioxide and temperature.

17. Paleoclimatic analysis has indicated that CO2 concentrations in the atmosphere have varied enormously; in the past up to ten fold higher than current levels. In the Milankovitch cycles, temperature rises precede those of CO2 and CO2 lags temperature during the falling phase.

18. Atmospheric CO2 levels deduced from ice cores have been rising since 1750. That observation is puzzling for the popular view, that all CO2 results from anthropogenic sources. The world population then was about a tenth of that today, fossil fuel use was largely limited to the UK and photosynthesis and the oceans should have sequestered any increase. The increase in CO2 in the 1800s is ascribed to massive forest clearing, supposedly reducing photosynthetic area, and increased use of wood for fuel. Even so there is no simple relation with population here. Subsequent industrialisation and fossil fuel use has left its isotopic mark in the atmosphere [Ghosh, P. Brand WA. International Journal of Mass Spectrometry 228 (2003) 1–33].

19. From 1880 onwards, direct measurements showed ocean surface temperatures declined for about 20 years and then have risen continually since. Like other direct temperature records, a century is a short time in climate terms. But the solubility of carbon dioxide in water is temperature dependent, so as global temperatures have risen, it is likely that less atmospheric CO2 will be absorbed and more dissolved CO2 will be released. This then gives rise to the question of whether it is CO2 that causes temperature increases, or temperature increases give rise to elevated atmospheric CO2, or a mixture of both.

20. Norwegian geoscientists [Humlum et al., 2013. Global Planetary Change 100, 51–69] have provided the first detailed analysis of the potential phase relationships between global temperature records, global CO2 levels, ocean surface temperatures and anthopogenic CO2 from 1980 to 2011, using Fourier analyses; the appropriate mathematical way to detect phase sequences.

21.Their exacting analysis has turned climate models on their head. These analyses indicate that temperature increases first in the ocean surface, followed by atmospheric temperature and then nearly a year later by atmospheric CO2. The lag in CO2 they ascribe to delays in mixing. They also report that anthropogenic CO2 is only a small contributor to the overall temperature.

22. I quote to indicate their conclusions. “As cause always must precede effect, this observation demonstrates that modern changes in temperatures are generally not induced by changes in atmospheric CO2. Indeed, the sequence of events is seen to be the opposite: temperature changes are taking place before the corresponding CO2 changes occur”. “Our figures 2–8 reveal that the common notion of globally dominant temperature controls exercised by atmospheric CO2 is in need of reassessment. Empirical observations indicate that changes in temperature generally are driving changes in atmospheric CO2, and not the other way around”. “Our analysis suggests that changes in atmospheric CO2 appear to occur largely independently of changes in anthropogene emissions. However, by this we have not demonstrated that CO2 released by burning fossil fuels is without influence on the amount of atmospheric CO2, but merely that the effect is small compared to the effect of other processes”. The conclusion of these authors is that the present high period of solar activity since 1920 may be responsible for the changes detected in atmospheric CO2.

23. While their analysis will no doubt be further examined, particularly by those with a vested interest in the status quo, these observations indicate why no government should have legislated on anthropogene emissions because the situation does not have the certainty originally claimed.

24. There is no direct relationship between rising atmospheric CO2 and global temperature, as the temperature stasis periods during the 40’s as well as from 1998 onwards indicate. However all models seemed to have assumed that rising CO2 must drive temperature increases , ever since Arrhenius identified the potential for CO2 as a greenhouse gas over 100 years ago. The paper by Professor Humlum and others is salutary in that things are not always what they seem.

25. Complex equations are used for climate models and the equations are constrained to fit known temperature changes. Using the relatively rapid temperature rise of the late 90’s to fit these equations might account for the continued increase in temperature that models predict but which failed to match actual observation. A Norwegian group has incorporated the present stasis in a model and calculated an acceptable 1.5◦ C rise for CO2 doubling.

Legislation on Climate Change should be Revoked.

26. I feel very strongly that legislation on climate change should not have been enacted. Climate science is young and there is a deal of uncertainty in its claims. Legislation has propelled us on a path which is difficult to retreat from but is going to inflict real damage on our economic activity and wealth because we are going to make our electricity, the life blood of all economic activity, the most expensive world-wide. No doubt the gesture of reducing emissions was considered noble but it has now turned into the ultimate gesture politics because no one else in the world is going to follow suit. This policy will merely accelerate the decline of the UK and Europe.

27. In seeking to understand the alacrity with which the popular view of climate change as being anthropogenic was incorporated into law, three additional reasons can be given as well as the assumption that temperature rises were mankind-induced.

(A).There is the claim by developing countries that western industry and society is guilty of the present state of atmospheric GHG. The West may have accounted for much atmospheric GHG but good use has been made by inventing mobile phones, tarmacked roads, railways, aeroplanes, the internet, computers, trains, modern agriculture and food abundance, modern transport, electricity and use of gas, metallurgy, books, science, antibiotics, vaccines, modern medicine, liners, steel ships, etc. The world has benefited.

(B).Highly-publicised agitation by well-funded, well-organised but largely unqualified ideological groups. Often self-righteous, they, seemingly, are against all human progress.

(C).Unreliable world sources of energy. Shale gas and hydraulic fracturing has changed the UK perspective. Methane can be derived from coal seams.

28. The effect of legislating on climate change was to emphasise renewables in generating policy on the basis that they are free at source. So are coal, oil and gas; exploitation is what costs. All “renewables” require huge areas of land or sea to gather energy (MacKay, DJC. Sustainable Energy without the Hot Air). Because of subsidies to these, there has been no financial driver to investigate alternatives that are recognisably less damaging to the countryside and seas. Even the use of thorium or modular nuclear reactors seems to have been discarded, despite the UK being at the forefront of nuclear technologies in the past. There’s enough uranium in the oceans to last for millions of years. The cost of renewables places the heaviest burdens on the poorest. The increasing proportion of renewables in electricity generation will eventually threaten its stability.

29. Criticism of claims about the extent of emissions reduction from renewables needs to be acknowledged.1 Renewables damage to the countryside is only perceived by those that live there but unspoilt countryside is at a premium in this crowded island.

30. Much is made of the supposed consensus on climate change but this was initiated by Arrhenius who identified CO2 as a GHG and who calculated that a doubling of CO2 would increase global temperature by 2◦ C, a value little different from most models. But Arrhenius’ knowledge of climate was limited and a major failing was not to include the negative feedback of clouds although he recognised the effect of water vapour on temperature. Since that time, climate scientists of all kinds tend not to think outside this box and are constrained to incorporate that simple idea that “CO2 must drive global temperature”. There is enough discrepancy to indicate that a reassessment of that simple idea is essential. Discarding Arrhenius’ simple relation as a simplification that does not match the real world would be a start. Climate is a very complex interactive system and systems properties are often counterintuitive.2 I suspect Professor Humlum’s group assessment will turn out to be more accurate than the popular view of climate.

31. It would help if the committee acknowledged the uncertainty.

April 2013

1 and Wheatleys article is “in press”

2 For example, car speed is a simple interactive system and most would intuitively identify the accelerator as the speed control. But changing down, brakes, going up or down hill etc., all contribute to speed, indicating the accelerator is not the simple control implied.

Prepared 1st April 2014