AMOC tipping slows permafrost carbon release during overshoot
Overshooting climate targets risks irreversible changes, but AMOC slowdown could slow permafrost carbon release, offering a glimmer of hope in the face of global warming.
This study used three climate models to assess the impact of climate mitigation scenarios on permafrost carbon release. The researchers found a robust linear relationship between permafrost carbon loss and time-integrated warming exposure during overshoot scenarios. Interestingly, a temporary slowdown in the Atlantic Meridional Overturning Circulation (AMOC) induced by overshoot can reduce permafrost carbon loss by 30% per 100 degree-years of AMOC-induced cooling, partially offsetting the impacts of climate change. These findings highlight the importance of considering both destabilizing and stabilizing Earth system feedbacks when evaluating the consequences of overshooting global warming targets, which is crucial for informing carbon budgets, net-zero planning, and the reversibility of climate change.