A realistic climate strategy

The international climate strategy is failing. Current policies will act too slowly to prevent rising temperatures from crossing critical climate tipping points. IPCC assessments underestimate the non-linear risks and catastrophic costs of overshooting Paris Agreement targets. Opponents of solar geoengineering cite concerns about moral hazard and other potential risks; however, at this juncture cooling interventions are the only feasible way to stop dangerous climate change. Worsening impacts will force many climate sceptics to address the crisis. They will increasingly support solar geoengineering, as these methods will allow global temperatures to be rapidly lowered without reducing emissions. Major powers are already researching climate geoengineering. In the near future one or more countries will almost inevitably deploy unilateral climate interventions to prevent increasingly extreme weather from causing massive crop failures and other deadly disasters. To forestall the unilateral deployment of untested technologies, an international program is urgently needed to research safe climate cooling methods and develop effective global governance. Solar geoengineering can reduce temperatures to safe levels, but will not stop rising concentrations of atmospheric greenhouse gases from acidifying the oceans and destroying critical marine ecosystems. Cooling interventions are imperative, but they must be used as supplements for existing strategies to reduce and remove greenhouse gases, not as substitutes. To ensure constructive outcomes, international dialogue and research must immediately begin on a new, viable climate strategy: supplementing greenhouse gas emission reduction and carbon dioxide removal with cooling interventions. There is no realistic alternative.