A natural or artificial system that absorbs more carbon dioxide (CO2) from the environment than it releases, serving as a tool to combat global warming.
A significant and lasting change in the statistical distribution of meteorological elements, calculated for different periods but relating to the same area.
A reconstruction of temperatures over the past 1,000 years prominently featured in the IPCC Third Assessment Report, commonly used to illustrate global warming.
An international agreement reached in 1987 to reduce the production and consumption of chlorofluorocarbons (CFCs) and halon, substances which deplete the ozone layer in the upper atmosphere.