Graeme MacDonald Taylor , Peter Wadhams, Daniele Visioni, Tom Goreau, Leslie Field, Heri Kuswanto

Although the 2015 Paris Agreement climate targets seem certain to be missed, only a few experts are questioning the adequacy of the current approach to limiting climate change and suggesting that additional approaches are needed to avoid unacceptable catastrophes. This article posits that selective science communication and unrealistically optimistic assumptions are obscuring the reality that greenhouse gas emissions reduction and carbon dioxide removal will not prevent climate change in the 21st Century. It also explains how overly pessimistic and speculative criticisms are behind opposition to considering potential climate cooling interventions as a complementary approach for mitigating dangerous warming.
There is little evidence supporting assertions that: current greenhouse gas emissions reduction and removal methods can and will be ramped up in time to prevent dangerous climate change; overshoot of Paris Agreement targets will be temporary; net zero emissions will produce a safe, stable climate; the impacts of overshoot can be managed and reversed; Intergovernmental Panel on Climate Change models and assessments capture the full scope of prospective disastrous impacts; and the risks of climate interventions are greater than the risks of inaction.
These largely unsupported assumptions distort risk assessments and discount the urgent need to develop a viable mitigation strategy. Owing to political pressures, many critical scientific concerns are ignored or preemptively dismissed in international negotiations. As a result, the present and growing crisis and the level of effort and time that will be required to control and rebalance the climate are severely underestimated.
The paper concludes by outlining the key elements of a realistic policy approach that would augment current efforts to constrain dangerous warming by supplementing current mitigation approaches with climate cooling interventions.