Despite major advances in climate science over the last 30 years, persistent uncertainties in projections of future climate change remain. Climate projections are produced with increasingly complex models that attempt to represent key processes in the Earth system, including atmospheric and oceanic circulations, convection, clouds, snow, sea ice, vegetation, and interactions with the carbon cycle. Uncertainties in the representation of these processes feed through into a range of projections from the many state-of-the-art climate models now being developed and used worldwide. For example, despite major improvements in climate models, the range of equilibrium global warming due to doubling carbon dioxide still spans a range of more than 3. Here a promising way to make use of the ensemble of climate models to reduce the uncertainties in the sensitivities of the real climate system is reviewed. The emergent constraint approach uses the model ensemble to identify a relationship between an uncertain aspect of the future climate and an observable variation or trend in the contemporary climate. This review summarizes previous published work on emergent constraints and discusses the promise and potential dangers of the approach. Most importantly, it argues that emergent constraints should be based on well-founded physical principles such as the fluctuation-dissipation theorem. This review will stimulate physicists to contribute to the rapidly developing field of emergent constraints on climate projections, bringing to it much needed rigor and physical insights.

中文翻译：

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对气候敏感性的新限制

尽管在过去30年中气候科学取得了重大进展，但对未来气候变化的预测仍存在不确定性。气候预测是通过越来越复杂的模型产生的，这些模型试图表示地球系统中的关键过程，包括大气和海洋环流，对流，云，雪，海冰，植被以及与碳循环的相互作用。这些过程表示的不确定性会导致来自全球目前正在开发和使用的许多最新气候模型的一系列预测。例如，尽管气候模型有了重大改进，但由于二氧化碳增加一倍而导致的全球平衡变暖范围仍然超过3。这里回顾了一种利用气候模型集合来减少真实气候系统敏感性不确定性的有前途的方法。涌现约束方法使用模型集合来识别未来气候的不确定方面与现代气候中可观察到的变化或趋势之间的关系。这篇综述总结了以前发表的关于紧急约束的工作，并讨论了该方法的前景和潜在危险。最重要的是，它认为出现的约束应基于有充分依据的物理原理，例如波动耗散定理。这次审查将刺激物理学家为迅速发展的气候预测紧急限制领域做出贡献，并为之带来急需的严谨和物理见解。