Geoengineering does little to defuse most of the risks that really matter for people – and it runs the risk of making some harms worse
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lanetary-scale solar geoengineering interventions involve the deliberate injection of either natural or artificial particulates into the stratosphere – stratospheric aerosol injection, or SAI – with a view to offset some of the global heating caused by greenhouse gases. If implemented, the technology would create a metaphorical thermostat for the planet. Such a thermostat is advocated on the grounds that controlling global temperature reduces the harms associated with the climate crisis.
I wish to challenge this assertion.
Global temperature was first adopted at the beginning of this century as a way of indexing the extent of human impact on the climate system. Since then, managing global temperature has become the primary object of climate policy, thus the Paris agreement’s stated aim being to contain global warming between 1.5C and 2C. The policy goal of net zero emissions is derived from this target temperature range.
