James Lovelock died on his 103rd birthday, according to his family.
The basis of climate science can be traced back to his 1960s theory of Earth.
Climate change could be a tipping point for the planet according to him.
Environmentalists criticized his support for nuclear energy.
Lovelock realized living things had a profound impact on the environment when he was working for the National Aeronautical and Space Administration.
Everything on Earth, from the oceans to the living organisms, was connected.
The idea was seen by some scientists as too young.
The basis of the green movement can be traced back to the theory.
The ozone layer was being destroyed by chemicals.
He was driven to reveal the threat posed to life by a warming world.
Lovelock said that they were playing a very dangerous game.
One of the major regulating mechanisms is being interfered with.
"My main reason for not relaxing into contented retirement is that, like most of you, I am deeply concerned about the probability of climate change and the need to do something about it now."
He said two years ago that the biosphere was on the verge of extinction.
James Lovelock passed away in his home surrounded by his family on his 103rd birthday.
He was best known as a scientist and climate prophet.
He was a loving husband and father with a passion for nature and a mischievous sense of humor.