Thank you for inviting me to this important and exciting occasion, the founding of the World Nuclear University.

I speak as a wholly independent scientist and my concern is - and has been for forty years - more for the Earth than for the people who inhabit it. This is not because I am a cold-hearted scientist who does not care for people but is because I think that our welfare as humans depends on the health of the Earth system, or as I prefer to call it, Gaia.

Scientists are at last beginning to recognise that the Earth behaves like a physiological system. It regulates its climate and chemical composition so as always to be habitable for whatever is the contemporary biosphere. We are fortunate to live on so benign a planet but we cannot expect to be free to interfere with its mechanisms - such as by altering the atmospheric composition or the nature of the surface-without incurring consequences.

A sizeable and representative group of scientists, the International Panel on Climate Change (IPCC) have considered these consequences. In their third report issued in 2001, they predicted that our continued burning of carbon fuel would lead to a global rise of temperature of between 1.5 and 6.0oC by the end of this century. These are serious consequences but neither the public nor the media seem to have expressed an appropriate concern. The most probable IPCC prediction - a rise of 3.5oC globally-does not seem much but it is, in fact, about the same as the difference in temperature between the last ice age and that in 1900 (just before global warming became apparent).

To give you some idea of the consequences of such a rise in global temperature, consider someone living, just over 10,000 years ago, in a coastal region of South East Asia in the milder climate of the ice age tropics. Who then could have imagined that in a short time the sea would rise 120 metres and put beneath the waves an area of land equal in size to the continent of Africa? Who then would have predicted the emergence of the tropical rain forests and a three-fold decline in ocean life? People survived through these changes and will survive through the severe but different changes to come, but civilization is much more fragile than individual humans.

This is why we have few alternatives but greatly to reduce the proportion of energy we take from the unsafe practice of burning carbon fuel. It would be wonderful if we could maintain civilization by renewable energy sources alone, but it is foolish fantasy to think that we could do it soon enough to avoid risking a greenhouse catastrophe. The only sensible and practical option is to use nuclear energy to supplement the meagre supplies of energy from foreseeable renewable sources. Nuclear electricity is now a well-tried and soundly engineered practice and is both safe and economic; given the will, we could apply it quickly. Yet disinformation about its dangers persists and sustains a climate of ignorance, which artificially inflates the cost of nuclear energy and of waste disposal.

I remember how proud we were when in 1956, Her Majesty the Queen, then a young woman, opened at Calder Hall, the world's first large scale civilian nuclear power station. At that time we looked on atomic energy as something desirable that would set us free. Unfortunately, the fear of nuclear war and the fear of radiation merged and fear alone, not sensible scientific or economic arguments, changed the public perception of nuclear energy. Because fear provides so good a story line, the media, Hollywood, fiction writers, sustain it and profit from it. They have elevated nuclear accidents to the status of religious icons and present them as the greatest industrial disasters of the 20th century. Even the BBC and the Times persist in spinning the Chernobyl accident by stating that thousands had died there. In fact, according to the UN study fourteen years after the event, forty-five died at Chernobyl; many of them were brave firemen and helicopter crews who tried to quench the fire. It was an awful event and caused great suffering, and it should never have happened, but it was far less lethal than the industrial accident at Bhopal in India or the never ending death toll of the coal and petroleum industries.

Perhaps the torrid heat this summer - which caused the death of more than thirty thousand Europeans - was the first warning of worse to come. It was hotter than can be remembered in the historic past but, more than this, it would have been two degrees Celsius hotter still, but for the cooling effect of the aerosol cloud that blankets Europe. Business as usual will lead us, sometime in the coming century, to the first devastating effects of global change; then we will look back and see what a vast disservice the media and our politicians had done. They gave in to false fears and failed to use the one safe large-scale source of energy. Those politicians unwise enough to preside over the closure of working nuclear power plants will have much to answer. Their monument will be the spinning windmills standing like the statues on Easter Island, reminders of a failed civilisation.

So let us recognise that the truly dangerous thing we do is burning fossil carbon. For the Earth, carbon dioxide is one of those insidious cumulative poisons whose consequences only become apparent when it is too late to stop. We are just now behaving like a new variant of the biblical Gaderene swine: we drive our polluting cars down to a sea that rises to drown us.

Ladies and gentlemen, I salute all those who have established this university. May it bring knowledge and wisdom and dispel the mists of fear and ignorance.