geoengineering explained: the benefits and challenges of ocean alkalinity enhancement

Ocean alkalinity enhancement is increasements in the ocean’s alkalinity via the exposure of large quantities of reactive minerals to carbon dioxide in the atmosphere. The resulting compounds are then stored in the ocean or soil. This form of geoengineering is known as carbon dioxide removal (CDR).



  • Increased solubility of CO2 in ocean waters
  • Sequestered carbon becomes inorganic carbon that stays in the ocean permanently
  • Expensive [estimates at more than 1 trillion USD]
  • There is a lack of infrastructure needed to effectively facilitate the transformation from limestone to quicklime
  • Has the potential to release more CO2 into the atmosphere if proper storage and capture facilities are not established
  • Can be harmful to biotic aquatic systems
  • Alkalinity must be significantly increased to produce worthwhile results

see also:

Question: What is geoengineering?

Albedo Enhancement

Space Reflectors
Stratospheric Aerosols

Ambient Air Capture
Bioenergy Capture and Sequestration
Ocean Fertilization
Enhanced Weathering
Ocean Alkalinity Enhancement


Ian S F Jones, C. H. (2003, May). Engineering Carbon Sequestration in the Ocean. Retrieved from
Francois S. Paquay, R. E. (2013, May 9). Assessing possible consequences of ocean liming on ocean pH, atmospheric CO2 concentration and associated costs. International Journal of Greenhouse Gas Control, pp. 183-188. Retrieved from