Tools are needed to benchmark carbon emissions and pledges against criteria of equity and fairness. However, standard economic approaches, which use a transparent optimization framework, ignore equity. Models that do include equity benchmarks exist, but often use opaque methodologies. Here we propose a utilitarian benchmark computed in a transparent optimization framework, which could usefully inform the equity benchmark debate. Implementing the utilitarian benchmark, which we see as ethically minimal and conceptually parsimonious, in two leading climate–economy models allows for calculation of the optimal allocation of future emissions. We compare this optimum with historical emissions and initial nationally determined contributions. Compared with cost minimization, utilitarian optimization features better outcomes for human development, equity and the climate. Peak temperature is lower under utilitarianism because it reduces the human development cost of global mitigation. Utilitarianism therefore is a promising inclusion to a set of benchmarks for future explorations of climate equity.

需要有工具根据公平和公正的标准来衡量碳排放和承诺。然而，使用透明优化框架的标准经济方法忽视了公平。确实存在包含股权基准的模型，但通常使用不透明的方法。在这里，我们提出了一个在透明优化框架中计算的功利基准，这可以为股权基准辩论提供有用的信息。在两个领先的气候经济模型中实施功利主义基准（我们认为该基准在道德上是最低限度的且在概念上是简约的）可以计算未来排放的最佳分配。我们将这一最佳值与历史排放量和国家确定的初始贡献进行比较。与成本最小化相比，功利主义优化可以为人类发展、公平和气候带来更好的结果。功利主义下的峰值温度较低，因为它降低了全球减缓的人类发展成本。因此，功利主义有望成为未来气候公平探索的一套基准。