I was on the Global Warming Gravy Train

Admission from Science Speak expert

The U.K. Daily Pundit featured this article yesterday and I thought it was worth following the links to satisfy my own curiosity and thirst for knowledge, I am one of those who perhaps are not yet fully convinced by the fashion, or the new evangelical religious-like zeal of the “green” politicians and their environmentalist string pullers. I have a healthy respect for science and have a healthy disdain for pollution too, and I have no problem with the ideas of making best use of the earth’s natural resources and using renewables wherever possible. Common sense dictates that many things are finite and our stewardship of the earth’s resources needs to be paramount.

On the other hand, until I am utterly convinced by an argument, until there is sufficient concensus to provide the basis for factual content, then I am perfectly entitled to hold a sceptical view of the current trend for politicians to jump on the carbon emissions bandwagon, is it just a nice fine way to raise taxes without raising riots? The trouble is of course, to express outright agreement with those who vehemently oppose the theory that CO2 emissions are mainly responsible for global warming and climate change, is to put oneself in the same category as holocaust deniers! Yet, it seems to me that this is how the “debate” is panning out, those who find data or formulae that contradicts the current version of environmental armageddon find themselves isolated, rejected, losing out on public finance for scientific projects and generally treated like a pariah.

David Evans is a mathematician, and a computer and electrical engineer, and is head of Science Speak, an organisation that was recently responsible for a huge carbon accounting and modelling exercise for the Australian government, and in a series of blog articles with a side wager involved (amounting to some thousands of dollars) he argues that perhaps CO2 emissions are not so important a factor in affecting global warming. Of course, once having published his thoughts he is instantly joined by other bloggers who refuse to give space to those they label “kooky denialist”

Iain Dale ran into the same problems with his post “How the Enviro-Fascists are trying to close down the climate change debate” which has attracted almost 200 very heated comments on Tuesday.

Here are a few extracts from the article by David Evans, you can read his full piece - here

“I devoted six years to carbon accounting, building models for the Australian government to estimate carbon emissions from land use change and forestry. When I started that job in 1999 the evidence that carbon emissions caused global warming seemed pretty conclusive, but since then new evidence has weakened that case. I am now skeptical.

In the late 1990s, this was the evidence suggesting that carbon emissions caused global warming:

1. Carbon dioxide is a greenhouse gas, proved in a laboratory a century ago.
2. Global warming has been occurring for a century and concentrations of atmospheric carbon have been rising for a century. Correlation is not causation, but in a rough sense it looked like a fit.
3. Ice core data, starting with the first cores from Vostok in 1985, allowed us to measure temperature and atmospheric carbon going back hundreds of thousands of years, through several dramatic global warming and cooling events. To the temporal resolution then available (data points more than a thousand years apart), atmospheric carbon and temperature moved in lockstep: they rose and fell together. Talk about a smoking gun!
4. There were no other credible causes of global warming.

I was on that gravy train, making a high wage in a science job that would not have existed if we didn’t believe carbon emissions caused global warming. And so were lots of people around me; there were international conferences full of such people. We had political support, the ear of government, big budgets. We felt fairly important and useful (I did anyway). It was great. We were working to save the planet!

But starting in about 2000, the last three of the four pieces of evidence above fell away. Using the same point numbers as above:

1. Better data shows that from 1940 to 1975 the earth cooled while atmospheric carbon increased. That 35 year non-correlation might eventually be explained by global dimming, only discovered in about 2003.
2. The temporal resolution of the ice core data improved. By 2004 we knew that in past warming events, the temperature increases generally started about 800 years before the rises in atmospheric carbon. Causality does not run in the direction I had assumed in 1999 — it runs the opposite way!

It took several hundred years of warming for the oceans to give off more of their carbon. This proves that there is a cause of global warming other than atmospheric carbon. And while it is possible that rising atmospheric carbon in these past warmings then went on to cause more warming (”amplification” of the initial warming), the ice core data neither proves nor disproves this hypothesis.

1. There is now a credible alternative suspect. In October 2006 Henrik Svensmark showed experimentally that cosmic rays cause cloud formation. Clouds have a net cooling effect, but for the last three decades there have been fewer clouds than normal because the sun’s magnetic field, which shields us from cosmic rays, has been stronger than usual. So the earth heated up. It’s too early to judge what fraction of global warming is caused by cosmic rays.

There is now no observational evidence that global warming is caused by carbon emissions. You would think that in over 20 years of intense investigation we would have found something. For example, greenhouse warming due to carbon emissions should warm the upper atmosphere faster than the lower atmosphere — but until 2006 the data showed the opposite, and thus that the greenhouse effect was not occurring! In 2006 better data allowed that the effect might be occurring, except in the tropics.

Unfortunately politics and science have become even more entangled. Climate change has become a partisan political issue, so positions become more entrenched. Politicians and the public prefer simple and less-nuanced messages. At the moment the political climate strongly blames carbon emissions, to the point of silencing critics.

The integrity of the scientific community will win out in the end, following the evidence wherever it leads. But in the meantime, the effect of the political climate is that most people are overestimating the evidence that carbon emissions are the main cause of global warming.

I recently bet $6,000 that the rate of global warming would slow in the next two decades. Carbon emissions might be the dominant cause of global warming, but I reckon that probability to be 20% rather than the 90% the IPCC estimates.

Politicians, expressing the anger and apparent futility of all the unnecessary poverty and effort, lead the lynching of the high priests with their opaque models. Ironically, because carbon emissions are raising the temperature baseline around which natural variability occurs, carbon emissions might need curbing after all. Maybe. The current situation is characterized by a lack of observational evidence, so no one knows yet.

Some people take strong rhetorical positions on global warming. But the cause of global warming is not just another political issue, subject to endless debate and distortions. The cause of global warming is an issue that falls into the realm of science, because it is falsifiable. No amount of human posturing will affect what the cause is. It just physically is there, and after sufficient research and time we will know what it is”.

In other words whilst the scientists are still not totally convinced of the cause of global warming I have to take a longer term “wait and see” approach to my own beliefs (despite some green lobbyists alarmist reactions that there is no time left for waiting.) Perhaps it is just a fashionable thing for politicians world wide to jump on the Al Gore bandwagon, or perhaps I’m a kooky denialist, we’ll just have to wait and see won’t we.