Climate change glossary

Adaptation Action that helps cope with the effects of climate change - for example construction of barriers to protect against rising sea levels, or conversion to crops capable of surviving high temperatures and drought.
Adaptation fund A fund for projects and programmes that help developing countries cope with the adverse effects of climate change. It is financed by a share of proceeds from emission-reduction programmes such as the Clean Development Mechanism.

Annex I countries The industrialised countries (and countries in transition to a market economy) which took on obligations to reduce their greenhouse gas emissions under the Kyoto Protocol. Their combined emissions, averaged out during the 2008-2012 period, should be 5.2% below 1990 levels.

Annex II Countries which have a special obligation under the Kyoto Protocol to provide financial resources and transfer technology to developing countries. This group is a sub-section of the Annex I countries, excluding those that, in 1992, were in transition from centrally planned to a free market economy.

Anthropogenic climate change Man-made climate change - climate change caused by human activity as opposed to natural processes.

Aosis The Alliance of Small Island States comprises 42 island and coastal states mostly in the Pacific and Caribbean. Members of Aosis are some of the countries likely to be hit hardest by global warming. The very existence of low-lying islands, such as the Maldives and some of the Bahamas, is threatened by rising waters.

AR4 The Fourth Assessment Report produced by the Intergovernmental Panel on Climate Change (IPCC) published in 2007. The report assessed and summarised the climate change situation worldwide. It concluded that it was at least 90% likely that the increase of the global average temperature since the mid-20th Century was mainly due to man's activity.

Atmospheric aerosols Microscopic particles suspended in the lower atmosphere that reflect sunlight back to space. These generally have a cooling affect on the planet and can mask global warming. They play a key role in the formation of clouds, fog, precipitation and ozone depletion in the atmosphere.