Greenhouse gas remediation
Greenhouse gas remediation projects are a type of geoengineering that seek to remove greenhouse gases from the atmosphere, and thus they tackle the root cause of global warming. These techniques either directly remove greenhouse gases, or alternatively seek to influence natural processes to remove greenhouse gases indirectly. The discipline overlaps with carbon capture and storage and carbon sequestration, and some projects listed may not be considered to be geoengineering by all commentators, instead being described as mitigation.
Carbon sequestration 
A wide range of techniques for carbon sequestration exist. These range from ideas to remove CO2 from the air, flue gases and by preventing carbon in biomass from re-entering the atmosphere, such as with BECCS.
CFC photochemistry 
Methane removal 
Methane potentially poses major challenges for remediation. It is around 20 times as powerful a greenhouse gas as CO2. Large quantities may be outgassed from permafrost and clathrates as a result of global warming, notably in the Arctic.
- Chemical decomposition — reaction with hydroxyl radicals produced from photochemical decomposition of ozone in the stratosphere.
- Biological decomposition — by methanotrophs in soils and water
See also 
- Wigley TM (October 2006). "A combined mitigation/geoengineering approach to climate stabilization". Science 314 (5798): 452–4. Bibcode:2006Sci...314..452W. doi:10.1126/science.1131728. PMID 16973840.
- Stix, T.H. (7-9 Jun 1993). "Removal of chlorofluorocarbons from the troposphere". 1993 IEEE International Conference on Plasma Science. Vancouver, BC, Canada: IEEE. p. 135. doi:10.1109/PLASMA.1993.593398. ISBN 0-7803-1360-7.
- "Methane as a Greenhouse Gas CCSP Research Highlight 1". U.S. Climate Change Science Program. January 2006.
- Buffett, B.; Archer, D. "Time-dependent response of the marine clathrate reservoir to climatic and anthropogenic forcing". American Geophysical Union. Spring. Meeting 2005. Bibcode:2005AGUSM.U33A..05B. 2005AGUSM.U33A..05B.
- "Methane Release from Arctic Clathrates Could Threaten Global Climate". International Polar Foundation. 4 June 2008.
- Stolaroff, J. K.; Bhattacharyya, S.; Smith, C. A.; Bourcier, W. L.; Cameron-Smith, P. J.; Aines, R. D. (2012). "Review of Methane Mitigation Technologies with Application to Rapid Release of Methane from the Arctic". Environmental Science & Technology 46 (12): 6455. doi:10.1021/es204686w.
- Lockley, A. (2012). "Comment on "Review of Methane Mitigation Technologies with Application to Rapid Release of Methane from the Arctic"". Environmental Science & Technology 46 (24): 13552–13553. doi:10.1021/es303074j.
- Reeburgh, William S., and David T. Heggie (1977). "Microbial methane consumption reactions and their effect on methane distributions in freshwater and marine environments". Limnology and Oceanography 22 (1): 1–9. doi:10.4319/lo.1977.22.1.0001.