Climate change mitigation involves taking actions aimed at reducing the extent of global warming. This is in contrast to adaptation to global warming which involves minimizing the effects.
To avoid dangerous climate change, the energy policy of the European Union has set a 2°C [3.6°F] limit to the temperature rise, compared to pre-industrial levels. Of this, 0.8°C has already taken place and another 0.5°C is already committed. The 2°C rise is associated with a carbon dioxide concentration of 400–500 ppm by volume; as of January 2007 it was 383 ppm by volume, and rising at 2 ppm annually. Unless significant action is taken soon the 2°C limit is likely to be exceeded.
Strategies for moving to a low-carbon economy include development of new technologies, particularly renewable energy; electric and hybrid vehicles; fuel cells; public transportion; zero-energy buildings; Zero-Net-Energy USA Federal Buildings; energy conservation; carbon taxes; enhancing natural carbon dioxide sinks; population control; and carbon capture and storage. Environmental groups also encourage individual-lifestyle and political action, as well as action by business.
The Kyoto Protocol, covering more than 160 countries and over 55% of global emissions provides an international mitigation framework. The United States, the world's largest greenhouse gas emitter; and Kazakhstan have refused to ratify the treaty. China and India, two other large emitters, have ratified the treaty but are exempt from cutting emissions. International talks on a successor to the treaty, which ends in 2012, have begun.