In light of the latest junk science from the UN's IPCC touting global warming , err "climate change", I thought it fitting to link to this article about James Lovelock.
Lovelock is was a leading light in the environmentalist movement.

From the article.

Green guru and geophysicist James Lovelock, considered one of the pioneering scientists of the 20th century, has officially turned his back on man-made global warming claims and the green movement’s focus on renewable energy. Lovelock conceived the Gaia theory back in the 1970s, describing the Earth’s biosphere as “an active, adaptive control system able to maintain the earth in homeostasis.”...

The newly skeptical Lovelock responded: ”Well, that’s my privilege. You see, I’m an independent scientist. I’m not funded by some government department or commercial body or anything like that. If I make a mistake, then I can go public with it. And you have to, because it is only by making mistakes that you can move ahead.”
Lovelock dismissed the entire basis for global warming concerns in his BBC television interview. “Take this climate matter everybody is thinking about. They all talk, they pass laws, they do things, as if they knew what was happening. I don’t think anybody really knows what’s happening. They just guess. And a whole group of them meet together and encourage each other’s guesses,” Lovelock explained.

Please, do yourself a favor and read the whole thing.

Just to gauge how big of a change that is, here are some earlier quotes.

Writing in the British newspaper The Independent in January 2006, Lovelock argued that, as a result of global warming, "billions of us will die and the few breeding pairs of people that survive will be in the Arctic where the climate remains tolerable" by the end of the 21st century.[27] He has been quoted in The Guardian that 80% of humans will perish by 2100 AD, and this climate change will last 100,000 years. According to James Lovelock, by 2040, the world population of more than six billion will have been culled by floods, drought and famine. Indeed "[t]he people of Southern Europe, as well as South-East Asia, will be fighting their way into countries such as Canada, Australia and Britain".[28]
"By 2040, parts of the Sahara desert will have moved into middle Europe. We are talking about Paris – as far north as Berlin. In Britain we will escape because of our oceanic position."[28]
"If you take the Intergovernmental Panel on Climate Change predictions, then by 2040 every summer in Europe will be as hot as it was in 2003 – between 110F and 120F. It is not the death of people that is the main problem, it is the fact that the plants can't grow – there will be almost no food grown in Europe."[28]
"We are about to take an evolutionary step and my hope is that the species will emerge stronger. It would be hubris to think humans as they now are God's chosen race."