The climate change timeline is a visual exploration of some key events in the history of climate science, from 1824 and projections of climate impacts in the future, to 2100. Individual items are illustrated, with further information on each subject. Click arrow to progress through the timeline
French physicist Joseph Fourier recognises the importance of the atmosphere in trapping heat and influencing the temperature of the Earth. He uses the analogy of a greenhouse.
Irish scientist John Tyndall undertakes laboratory experiments, identifying water vapour and carbon dioxide as heat-trapping gases.
Swedish chemist Svante Arrhenius makes the first climate prediction; halving CO2 could lead to an Ice Age, doubling CO2 could lead to an increase in global temperature of 5 °C.
Engineer Guy Stewart Callendar first suggested that fossil fuel burning was responsible for the observed warming of the world's climate. He predicts a rise of 2 °C for a doubling of CO2 with poles warming most.
American scientist Charles David Keeling makes the first direct measurement of atmospheric CO2, on Mauna Loa, Hawaii (316 parts per million). The Keeling curve will become a crucial tracker of CO2 rise.
Manabe and Wetherald produce the first 3D model simulation of the effect of doubling CO2, producing many of the features seen in current models — stratospheric cooling, enhanced warming at high latitudes and an enhanced water cycle.
The first World Climate Conference voices concern that “continued expansion of man's activities on earth may cause significant extended regional and even global changes of climate”.
The IPCC is set up by the UN to provide policy-makers with a source of information on the causes and impacts of climate change, and adaptation and mitigation options to respond to it.
The First Assessment Report of the IPCC is published: it states that human activities are significantly adding to concentrations of greenhouse gases and global temperatures have risen by 0.5 °C over the previous 100 years.
Mount Pinatubo erupts, injecting sulphate aerosols high into the atmosphere and causing the global temperature to fall for two years before making a recovery.
The Kyoto Protocol sets binding targets for greenhouse gas reductions by industrialised nations of 5% against 1990 levels, over the five-year period 2008-2012.
Globally it is the warmest year ever recorded, enhanced by a strong El-Niño.
The IPCC states that most of the warming over the last 50 years is likely (greater than 66% probability) to have been caused by man-made greenhouse gases. This is its strongest statement to date on man's contribution to climate change.
Europe experiences its worst heatwave in 500 years, leading to an estimated 30,000 additional deaths.
The Kyoto Protocol comes into force following its ratification by Russia. Globally it is the second warmest year on record. Global temperatures have risen by 0.74 °C over the last 100 years.
The IPCC (Fourth Assessment Report) declares that warming of the climate system is unequivocal (as evident from observations), and most of the recent warming is very likely (>90% probability) to be the result of human activity. Arctic sea ice shrinks to its lowest extent since records began.
CO2 concentrations stand at 384 part per million, an increase of 37% since the start of the industrial era and higher than at any time in, at least, the last 850,000 years.
A global temperature increase of around 0.4 °C above 2005 levels is expected.
Summer Arctic sea ice is predicted to disappear.
World temperatures expected to rise by between 1.8-4.0 °C, depending on future greenhouse gas emissions.