Geoengineering has been proposed as a potential third option for tackling global warming, alongside mitigation and adaptation. Scientists do not typically suggest geoengineering the climate as an alternative to emissions control, but rather an accompanying strategy. Reviews of geoengineering techniques for climate control have emphasised that they are not substitutes for emission controls and have identified potentially stronger and weaker schemes.

The Intergovernmental Panel on Climate Change (IPCC) concluded in 2007 that geoengineering options for climate change "remained largely speculative and unproven." The costs, benefits, and risks of many geoengineering approaches to climate change are not well understood. However, in the 2013 Fifth Assessment Report (AR5), the IPCC concluded that "Modelling indicates that SRM methods, if realizable, have the potential to substantially offset a global temperature rise, but they would also modify the global water cycle, and would not reduce ocean acidification."