BBC NEWS Science/Nature Global warming: Crisis for Earth?

The BBC is to gather expert evidence this week on whether human-induced climate change is a crisis for planet Earth, as James Lovelock believes.
The originator of the Gaia concept wrote in his recent book "...the fever of global heating is real and deadly".
He says nuclear power is the only short-term way to provide enough energy without causing more climatic harm.
The BBC has commissioned a panel of scientists to review Professor Lovelock's evidence and opinions.
Panel members include top British experts on the Antarctic, climate modelling, interactions between oceans and atmosphere, and sustainable development.
It will meet on Monday and Tuesday, with conclusions and comments reported on Thursday on Radio 4's Today programme and on the BBC News website.
Goddess on the edge
We may truly be in grave danger... few of the present inhabitants of the earth are likely to survive beyond the 21st Century
James LovelockThe Revenge of Gaia, published earlier this year, is the latest in a series of books in which James Lovelock has developed the Gaia theory, which takes its name from the goddess of the Earth, or the Earth Mother, in Greek mythology.
The key idea is that the segment of Earth from the bottom of its crust to the top of its atmosphere acts as a self-regulating being, keeping conditions suitable for life.
A subtitle for Gaia theory is "the science of planetary medicine"; and in The Revenge of Gaia, James Lovelock argues that the planetary patient is seriously unwell.
"In January 2004, Sandy [his wife] and I were invited to the Hadley Centre in Exeter [part of the UK Met Office], and that visit made us both aware of the deadly seriousness of the Earth's condition," Professor Lovelock told the BBC News website.
"We discussed the rapid melting of ice floating on the Arctic Ocean, and the way that Greenland's glaciers are vanishing. We talked about global heating in the tropics and the threat to the forests there, and about the response of the great boreal forests of Siberia and Canada to climate change.

Lost bond with animate Earth
Too crowded for Utopia "It was a deeply gloomy picture; but for me the gloomiest of all things was the detached, almost academic, air with which the grim predictions were presented - almost as if we were discussing some other planet, not the Earth."
Professor Lovelock intends The Revenge of Gaia to be a "wake-up call" to spread awareness that "the Earth is truly in danger".
Nuclear solution
But is he right? Are the Earth's regulatory systems in crisis, with temperatures heading inexorably for a higher level, unpleasant and perhaps uncontrollable?
If he is, what should we make of his contention that renewable energy and the traditional concept of sustainable development are misguided?
Is he right to say that nuclear fission is the only way to provide humanity with the energy it needs until technologies such as nuclear fusion and tidal power can be introduced to a substantial extent? Does "a lack of constraint on the growth of population" lie at the root of modern environmental problems?

Are new nuclear reactors like Finland's Olkiluoto the way forward?James Lovelock's genius has perhaps been to bring such threads together into a logical whole.
"He is a superb scientist, an originator of the view of the Earth, including its life, as a complete interacting system and an all-round free thinker," said Professor Brian Hoskins of Reading University who will chair the panel.
"I hope we can explore Jim's views on why the problem of climate change is so serious, and see if we can agree that it should be a clarion call for positive action rather than the bleak view that some have taken from it."
Professor Lovelock is adamant that his book and his thesis is not defeatist, as some observers have suggested.
"Only those lacking imagination would take the book as a counsel for despair," he said.
"I am hoping that... The Revenge of Gaia will be taken seriously, together with the recognition that we may truly be in grave danger and that few of the present inhabitants of the Earth are likely to survive beyond the 21st Century.
"It would be wonderful to have positive and sensible suggestions for civilised adaptation."
Richard.Black-INTERNET@bbc.co.uk
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