The Lavoisier Group 2007 Workshop Rehabilitating Carbon Dioxide

'Rehabilitating Carbon Dioxide': An Overview

Ray Evans

The papers presented at the Lavoisier Group's Workshop Rehabilitating Carbon Dioxide held in Melbourne on 29th and 30th June 2007, covered the two most important scientific issues at the heart of the current debate over global warming and its causes. The first is the influence, if any, of atmospheric carbon dioxide on the earth's climate. The second is the very well documented correlation between sunspot activity and climate changes during the last 1500 years or more.

In addition, two papers were given on economic issues that are consequent to the claims of anthropogenic control of our climate. The paper by Alex Robson discusses the Shergold Report, a report commissioned by the Prime Minister from a committee chaired by the Secretary of the Department of Prime Minister and Cabinet, Peter Shergold, on the merits of a cap and trade scheme of licences required by law to emit carbon dioxide. The paper by Tim Curtin analyses the Stern Review, a report published with great fanfare in October 2006 and submitted to the then UK Chancellor of the Exchequer, Gordon Brown, on the costs and benefits of introducing a regime of decarbonisation for the UK.

It is noteworthy that Sir Nicholas Stern was released by Gordon Brown the day after the latter's Budget failed to adopt any of Stern's recommendations, but Peter Shergold continues as Secretary of PM&C.

This overview will discuss the two key science issues of this debate; first the influence of atmospheric carbon dioxide on climate; and second the connection between sunspots and climate.

It has been understood for at least twenty years that the physics of black-body radiation, described in the Stephan-Boltzmann black-body radiation curves (which used to be taught in high school physics courses), coupled with the radiation properties of carbon dioxide molecules, lead inexorably to the conclusion that once concentrations of carbon dioxide in the atmosphere exceed 50 ppmv, further increments of CO2 have an ever declining influence on the radiation balance at the outer surface of the atmosphere, and thus on the earth's temperature. The greenhouse contribution of CO2, already very small when compared with water vapour, gives the same small increase in global temperatures as it increases from 100 to 200 ppmv, from 200 to 400 ppmv, from 400 to 800 ppmv, and from 800 to 1600 ppmv. Each doubling of CO2 yields a predicted 0.4 deg C increase in temperature, an increment which can be overwhelmed by changes in cloud cover in the lower atmosphere.

This understanding of basic physics is briefly discussed in the 1990 IPCC's First Assessment Report but has not been mentioned in IPCC publications since.

It was covered at length in David Archibald's paper, in Bill Kininmonth's paper, in Michael Hammer's paper, and in Tom Quirks' analysis of atmospheric carbon 14, and the implications are far reaching. It means that atmospheric carbon dioxide has played virtually no role in influencing our climate since concentrations exceeded 200 ppmv during the last glacial maximum 20,000 years ago, and will play no discernible role in the future, regardless of the size of any increase of these concentrations. All of the huffing and puffing at the G8 or wherever these issues are discussed by heads of government and their officials is completely beside the point. Whether anthropogenic emissions of carbon dioxide are reduced or increased will make no discernible difference to the radiation balance and thus to global temperatures.

This is so basic a point, and so terminal for the decarbonisation ambitions of the Environmentalist movement, that it is a matter of concern and astonishment that it has not been pursued by the Kyoto sceptics (such as the Lavoisier Group) far more vigorously than it has been. Whatever our sins of omission in the past have been, we will be trying to make amends in the immediate future.

If carbon dioxide (once it has exceeded 50 ppmv) has virtually no impact on the radiation balance and thus on climate (and there was never any evidence that it did) where can we find some rational explanation for the climatic changes that have taken place during the last two millennia, for example the Roman Warm Period, the Mediaeval Warm Period, the Little Ice Age, and the warming which has taken place since about 1880, the 20th Century Warm Period?

Two papers at the workshop discussed the long-established connection between sunspots and climate. One of the earliest learned papers on this topic was written in 1801 by the discoverer of the planet Uranus, William Herschel, who found an excellent correlation between the history of wheat prices given by Adam Smith in the Wealth of Nations and the sun spot cycle for the same period. David Archibald took his analysis of this phenomenon to the point where he predicted a repeat during the next 23 years of the Dalton Minimum of 1796 to 1820, a period of low temperatures, little sunshine, and severe food shortages in Europe, particularly in Britain, which experienced a year without summer in 1816.

Will Alexander discussed the river flow records from the Nile, which go back to 640 AD, the longest record of its kind, and the 22-23 year periodicity which characterises that record.

So the connection between sunspots and climate change has long been observed but, up until 2005, never been explained. And here we introduce Henrik Svensmark, the Danish physicist, who in December 2004 began his experiments in the basement of a university building in Copenhagen which eventually proved that cosmic rays from far beyond the solar system, called galactic cosmic rays, were primarily responsible for initiating cloud formation in the lower atmosphere.

This was the missing link in the chain of causation between sunspots and climate. The first step in the chain is the realisation that sunspots are a manifestation of dramatic changes in the Sun's magnetic field. This immense field, which projects solar influence far out into space, and which envelopes the earth, exhibits a 22-23 year cycle, the Hale cycle, or two sunspot cycles back to back. (Each sunspot cycle of approximately 11 years is called the Schwabe cycle.) When the solar magnetic field is strong, it protects the earth from galactic cosmic rays, and thus cloud formation is greatly diminished. When it is weak (as during the Dalton Minimum) then cosmic rays penetrate easily into the lower atmosphere and cloud cover is correspondingly increased.

Clouds are the big influence on our climate. When abundant, they reflect the Sun's radiation back into space and the earth gets cold. When sparse, the Sun's radiation travels unimpeded to the surface of the earth and the earth warms. Cloud cover is the driver of climate, and cosmic rays determine in large measure the extent of that cloud cover.

The General Circulation Models, which are used by the IPCC to predict the response of the earth to increasing atmospheric carbon dioxide, describe cloud behaviour very badly. The representation of clouds is largely statistical and thus ignores interaction with terrestrial radiation and the energy exchanges of the hydrological cycle. More recently, it has been shown that the computer models underestimate the variation of surface evaporation and precipitation with changing surface temperature, a fatal flaw in the projection of changing surface temperature with radiation forcing.

These computer models, then, which have soaked up billions of dollars in programming and computer time, are worthless.

Svensmark should win the Nobel prize for his pioneering work in this field and the basement which housed his big box containing atmospheric gas will become as famous as the squash court at the University of Chicago where Enrico Fermi built the first atomic pile and demonstrated the first nuclear chain reaction.

Having completed the chain of causation from sunspots to climate, the next big step forward is in predicting the future behaviour of the Sun's magnetic field. David Archibald presents a number of different forecasts, but on the basis of empirical rules opts for a repeat of the Dalton minimum.

Svensmark himself is much more cautious. In the book co-authored with Nigel Calder The Chilling Stars: A New Theory of Climate Change, published in Australia by Allen and Unwin, they write (p 222):

Cosmic rays conform only loosely with the sunspot count. Although generally high when sunspots are few, and reduced when there are many, there is no simple one-one connection.

The next few years will be exciting for those who are involved in this field of scientific activity. If we experience something like a repeat of the Dalton Minimum the anthropogenists will have a lot of crow to eat, but that will be of small consequence compared with the economic upheavals caused by loss of agricultural production in the grain growing regions of North America and Northern Europe. Australian agricultural production will become more important in such a situation.

It is important at this time that Australia does nothing to impede its economic growth and its potential to play an increasingly important role in the global economy. The Shergold endorsement of a carbon emissions trading scheme is arguably one of the most lunatic documents in the history of official advice to Australian governments, and it should be buried without delay. If the next twelve months give us continuing cool weather, high rainfall and consequent flooding, then there is a real chance that such burial can take place without too much fuss.

Climate change has played a pivotal role in human history. During the Mediaeval Warm Period (850-1300 AD) European civilisation made huge progress in the arts and sciences, in agriculture, in technology, and in the formation of cities such as Florence, Milan, Genoa, and Venice, where the foundations of our market economies were established. With the advent of the Little Ice Age, Europe suffered a massive loss of population and it was not until 1550 that the population recovered to pre-1300 levels.

The belief that mankind can 'stop climate change' by decarbonising our economy is as irrational a belief as one can find in any primitive religion. But in legislating for carbon emission trading schemes we are declaring our commitment to superstition of the most primitive kind. If the recent discoveries of the power of galactic cosmic rays to influence cloud formation become more widely known, faith in anthropogenic carbon dioxide as the controlling force on climate will become a joke and Australia will be able to build urgently needed power stations, and develop major natural gas fields, without the burden of sovereign risk now attending such investments. Let us achieve this ambition as soon as possible.