Geoengineering – the deliberate attempt to manipulate large scale elements of the Earth’s climate system to reduce the impact of climate change – has recently started to build momentum in scientific, policy and popular discussions.

Proposed geoengineering techniques have typically focused on enhancing carbon sequestration (either directly, by capturing carbon dioxide emissions, or indirectly, by stimulating oceanic phytoplankton blooms), or managing solar radiation (via the release of stratospheric sulphur aerosols, or cloud reflectivity enhancement).

The science of this is (to me at least!) fascinating, and can indeed contribute much to our understanding of the complexity of the planetary climate. For that reason I at least partly agree with those (such as Bill Gates and Richard Branson) who support such research.

Yet the question that must be asked here is a science communication one – could such projects ever truly gain enough public support to get off the ground? Would mass popular consent ever exist for the release of stratospheric sulfate aerosols to create a global dimming effect? Given the complexity and scale of the issue, should we even try to have a public dialogue on such options? Continue reading →