Determining international climate mitigation response strategies is a complex task. Integrated Assessment Models support this process by analysing the interplay of the most relevant factors, including socio-economic developments, climate system uncertainty, damage estimates, mitigation costs and discount rates. Here, we develop a meta-model that disentangles the uncertainties of these factors using full literature ranges. This model allows comparing insights of the cost-minimising and cost-benefit modelling communities. Typically, mitigation scenarios focus on minimum-cost pathways achieving the Paris Agreement without accounting for damages; our analysis shows doing so could double the initial carbon price. In a full cost-benefit setting, we show that the optimal temperature target does not exceed 2.5 °C when considering medium damages and low discount rates, even with high mitigation costs. With low mitigation costs, optimal temperature change drops to 1.5 °C or less. The most important factor determining the optimal temperature is the damage function, accounting for 50% of the uncertainty.

确定国际缓解气候变化的战略是一项复杂的任务。综合评估模型通过分析最相关因素的相互作用来支持此过程，这些因素包括社会经济发展，气候系统不确定性，损害估计，减缓成本和贴现率。在这里，我们开发了一个元模型，可以使用完整的文献范围来消除这些因素的不确定性。该模型允许比较成本最小化和成本收益建模社区的见解。通常，缓解方案的重点是在不考虑损害的情况下实现《巴黎协定》的最低成本途径；我们的分析表明，这样做可能会使初始碳价提高一倍。在完整的成本效益设置中，我们表明最佳温度目标不超过2。考虑中等损失和低折现率时，即使具有较高的缓解成本，仍为5°C。在较低的缓解成本下，最佳温度变化降至1.5°C或更低。决定最佳温度的最重要因素是损伤函数，占不确定性的50％。