+ Cardinal George Pell, Archbishop of Sydney
24 May 2009
The tide on climate change is starting to turn. The Australian government is becoming more cautious.
It is rare to read a new book likely to make a huge difference to public opinion. Professor Ian Plimer's 500 page book with 2300 footnotes "Heaven and Earth. Global Warming: The Missing Science" is such a book. 30,000 copies were sold in its first month.
Plimer is not a climate change denier, because history shows the planet is dynamic and the climate is always changing, sometimes drastically.
Ice Ages have come and gone and we don't know why. History has seen glaciers at the equator and at one time Scandinavia was under 5 kilometres of ice. Sea levels have been 130 metres lower than today. Some consolation comes from the fact that ice sheets predominated for only 20 per cent of the earth's history.
Plimer demonstrates that a considerable amount of scientific evidence has been produced to counter the still predominant view that human activity, especially through industry, has polluted the atmosphere with carbon dioxide, which will produce disastrous climate changes including a rise in temperature, a melting of the ice caps and rising sea levels.
Contrary evidence is already changing the debate. Australia, with its tiny economy, is no longer aiming to lead the world. The threat of massive job losses and increasing awareness of new evidence will provoke even greater caution in the future.
Originally we were warned about the "greenhouse effect"; then it was "global warming", followed in turn by "climate change". Now we talk about reducing the "carbon footprint". The light is dawning and 30 per cent of scientists are sceptics or deniers.
Non-scientists should not blindly follow expert opinion and this includes Plimer. To the extent we can, we should examine their evidence. While it is still early days in the debate, Plimer's critics have been heavy with the abuse and short on counter evidence.
We should also look back at history for more accurate information and ignore computer models of the long-term future. Climate models making claims for decades into the future cannot work, because we do not know enough about many factors which influence weather, such as the level of activity of the sun, the earth's orbit and wobbles, the level of cloud cover, volcanoes.
One basic claim of Plimer is that an increase of carbon dioxide does not cause temperature rises, but might follow such rises.
What do we make of these facts? The carbon dioxide in the atmosphere continues to rise, but the world's temperature has not risen since 1998.
In Roman times and in the Medieval Warming (900 - 1300 A.D.) temperatures were higher than today by five and six degrees Celsius. No industries then!
In different Ice Ages the earth's atmosphere contained five and ten times the amount of carbon dioxide today.
Evidence shows the wheels are falling from the climate catastrophe bandwagon.