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The Atlantic meridional overturning circulation (AMOC) is an important tipping element in the climate system. There is a large uncertainty whether the AMOC will start to collapse during the century under future climate change, as this requires long climate model simulations which are not always available. Here, we analyze targeted climate model simulations done with the Community Earth System Model (CESM) with the aim to develop a physics-based indicator for the onset of an AMOC tipping event. This indicator is diagnosed from the surface buoyancy fluxes over the North Atlantic Ocean and is performing successfully under quasi-equilibrium freshwater forcing, freshwater pulse forcing, climate change scenarios, and for different climate models. An analysis consisting of 25 different climate models shows that the AMOC could begin to collapse by 2063 (from 2026 to 2095, to percentiles) under an intermediate emission scenario (SSP2-4.5), or by 2055 (from 2023 to 2076, to percentiles) under a high-end emission scenar

Societies increasingly rely on scientists to guide decisions in times of uncertainty, from pandemic outbreaks to the rise of artificial intelligence. Addressing climate change is no different. For governments wanting to introduce ambitious climate policies, public trust in climate scientists is pivotal, because it can determine whether voters support or resist those efforts.

New research suggests social transformations that prompt “degrowth” could cut humanity’s climate footprint in time to meet the Paris climate agreement target.