Science is providing hard evidence to support what is a pretty obvious guess: Geoengineering our way out of climate change might not work and would have unintended consequences. It still might end up being our only chance. From Simon Redfern’s BBC report about the European Geosciences Union General Assembly:

It is not at all obvious what the other consequences of global geoengineering approaches might be. For example, Patrick Applegate from Pennsylvania State University, reported that solar radiation management may yet fail to prevent sea-level rise from melting ice sheets, which respond on much longer time scales than the temperature effects of solar shielding.

Aside from being ineffective in stemming sea-level rise, solar radiation management – according to results from Jerry Tjiputra at Bergen University – would lead to increased ocean acidification in the North Atlantic.

These results also suggest that climate engineering could not offer a long-term solution, with the world eventually being in the same place, by 2200, as it would reach without any geoengineering interventions.

Asked whether he believed solar radiation management would be deployed, Prof [Ken] Caldeira responded: “A lot has to do with how bad climate change will end up being. Humans are quite adaptable as a species.

“On the other hand, projections for summers in the tropics suggest almost every summer will be hotter than the hottest summer yet on record, associated with crop failures. There is the possibility that there would be widespread crop failures in the tropics in the summer.

“The only thing a politician can do to start the planet cooling is solar geoengineering. If a catastrophic outcome does occur, the pressure to deploy a scheme could be overwhelming.•