Footnote to the preceding

This is from The Independent article.

CO₂ on the increase

1958: A US scientist, Charles Keeling, begins measuring the atmospheric concentration of carbon dioxide (CO₂) on an extinct volcano in Hawaii. It stands at 315 parts per million (ppm).

1968: The US spacecraft 'Apollo 8' takes the first pictures of Earth from a distance, beautiful but fragile - which help start modern environmentalism. The CO₂ level has reached 323ppm.

1972: The UN Conference on the Human Environment in Stockholm - the moment when the world first recognises environmental threats to the Earth as a whole. CO₂ now at 327ppm.

1988: The world wakes up to the danger of climate change, with an outspoken warning from scientists, and a speech by Margaret Thatcher. CO₂ level stands at 351ppm.

1992: The Earth Summit at Rio de Janeiro sees more than 100 countries sign the UN Framework Convention on Climate Change, the first global warming treaty. CO₂ now at 356ppm.

1995: The Kyoto protocol to the UN's climate treaty is signed in Japan, binding countries, including the US, to make cuts in their CO₂ emissions. The CO₂ level has now reached 360ppm.

2000: Obvious that the 1990s were the hottest decade in the global temperature record, with 1998 the hottest year in the northern hemisphere for 1,000 years. CO₂ is 369ppm.

2001: George Bush withdraws the US, the world's biggest CO₂ emitter, from Kyoto, alleging it will damage America's economy - jeopardising the whole process. CO₂ level now at 371ppm.

2003: First two weeks of August are the hottest period ever recorded in western Europe: 35,000 people die. New record high temperature for Britain. CO₂ now at 375ppm.

2004: After much dithering, Russia ratifies Kyoto, enabling the protocol to enter into force despite the desertion of the United States. But that doesn't stop the CO₂ level rising to 377ppm.