This article is part of Nature's Climate Change 2007 special.

Climate Change 2007

“This may be remembered as the day the question mark was removed from whether human activity has anything to do with climate change.”

Achim Steiner, head of the United Nations Environment Programme

“Now is not the time for half measures. It is the time for a revolution.

French president Jacques Chirac

“The question is, what can we do now? There's very little we can do about arresting the process.”

Anote Tong, president of the Pacific island nation of Kiribati

“This should compel all of us towards action rather than the paralysis of fear.”

Martin Rees, president of the United Kingdom's Royal Society

“Now it's time for us — the policymakers — to do our jobs.”

Bart Gordon, Democratic Congressman from Tennessee and chair of the US House Committee on Science

“This is a group of climate experts attempting to reach a scientific consensus. It doesn't commit governments to any course of action.”

Pradipto Ghosh, senior official at India's Ministry of Environment and Forests

“For sure, humans cause global warming!”

Headline from China's Xinhua news agency

“Let's be realistic. You can only run power stations in a modern Western economy on fossil fuel, or, in time, nuclear power.”

Australian prime minister John Howard, whose country has not ratified the Kyoto protocol

“Those who continue to ignore the threat will be doing the greatest disservice imaginable to current and future generations.”

Marthinus van Schalkwyk, environmental affairs minister for South Africa