1896: Svante Arrhenius predicted that increases of atmospheric CO2 from burning fossil fuels would lead to global warming; a doubling of atmospheric CO2 could cause global average temperature to rise by 5ºC. The predictions of this Nobel Prize laureate (1903) went unnoticed for more than half a century.
1958: First continuous monitoring reveals rapidly rising CO2 levels in the atmosphere.
1970s: Beginning of period of atmospheric warming known as “global warming”.
1988: UN establishes the Intergovernmental Panel on Climate Change (IPCC) to assess the science of climate change.
1990: IPCC’s First Assessment is published. The year is subsequently established as the baseline year for future emissions targets.
1992: Earth Summit meets in Rio de Janeiro. Governments agree on the UN Framework Convention on Climate Change (UNFCCC), which commits them to preventing “dangerous climate change”.
1995: After a fierce debate, in particular with OPEC nations, the IPCC Second Assessment establishes the strong link between human-induced greenhouse gases and climate change, saying that “the balance of evidence suggests….” that global warming is caused by mankind.
1997: Kyoto Protocol is agreed under UNFCCC. It includes the first emissions reduction targets for industrialized countries, covering 2008-2012; all major nations sign up.
1998: Warmest year in warmest decade in warmest century for at least a thousand years.
2001: Nations agree on methodological and other details of the Kyoto Protocol in Marrakech. The USA and Australia refuse to ratify the protocol.
2003: European heat wave, which kills more than 30,000 people. Scientists later conclude it is the first extreme weather event definitely attributable to human-induced climate change. Scientists report a third of the world afflicted by droughts, double the figure for the 1970s.
2005: Drought temporarily turns Amazon rainforest from a carbon sink to a carbon source.
2007: Massive summer ice loss in the Arctic brings fears of an ice-free north; IPCC Fourth Assessment warns of faster and irreversible climate change; Bali Climate Conference lays out timetable for agreeing successor to Kyoto Protocol.
2008: Poznan Climate Conference in Poland; slow progress on negotiations as many wait for the new Obama administration in the USA to declare its hand.
2009: Make or break year for the climate, with negotiations continuing for a Copenhagen Protocol set to conclude in December.
2010: After a rather disappointing result of the Copenhagen talks, international climate policy picks up momentum at the well-organiozed 16th Conference of the Parties in Cancun, Mexico.