Global temperature stabilization via controlled albedo enhancement of low-level maritime clouds

• Published in: Philosophical transactions of the Royal Society of London. Series A: Mathematical, physical, and engineering sciences Vol. 366; no. 1882; pp. 3969 - 3987
• Main Authors: Latham, John, Rasch, Philip, Chen, Chih-Chieh, Kettles, Laura, Gadian, Alan, Gettelman, Andrew, Morrison, Hugh, Bower, Keith, Choularton, Tom
• Format: Journal Article
• Language: English
• Published: London The Royal Society 13.11.2008
• Subjects: Aerosols; Albedo; Albedo Enhancement; Climate change; Climate models; Cloud Albedo; Cloud seeding; Clouds; Computer Simulation; Conservation of Natural Resources - methods; Cooling; Disasters - prevention & control; Ecosystem; Engineering - trends; Global Cooling; Greenhouse Effect; Models, Theoretical; Negative Forcing; Oceans; Sea water; Seeding Maritime Clouds; Stratocumulus clouds; Temperature; Weather
• ISSN: 1364-503X; 1471-2962
• DOI: 10.1098/rsta.2008.0137

Analytical calculations, cloud modelling and (particularly) GCM computations suggest that, if outstanding questions are satisfactorily resolved, the controllable, globally averaged negative forcing resulting from deployment of this scheme might be sufficient to balance the positive forcing associated with a doubling of CO
concentrations might be achieved by seeding low-level, extensive maritime clouds with seawater particles that act as cloud condensation nuclei, thereby activating new droplets and increasing cloud albedo (and possibly longevity). This paper focuses on scientific and meteorological aspects of the scheme. Associated technological issues are addressed in a companion paper.
An assessment is made herein of the proposal that controlled global cooling sufficient to balance global warming resulting from increasing atmospheric CO
concentration. This statement is supported quantitatively by recent observational evidence from three disparate sources. We conclude that this technique could thus be adequate to hold the Earth's temperature constant for many decades.
More work—especially assessments of possible meteorological and climatological ramifications—is required on several components of the scheme, which possesses the advantages that (i) it is ecologically benign—the only raw materials being wind and seawater, (ii) the degree of cooling could be controlled, and (iii) if unforeseen adverse effects occur, the system could be immediately switched off, with the forcing returning to normal within a few days (although the response would take a much longer time).