Utrecht Researcher Models Bering Strait Dam as Potential AMOC Stabilisation Option

A PhD researcher at Utrecht University has used climate models to test whether closing the Bering Strait with a dam could stabilise the Atlantic Meridional Overturning Circulation, finding that in some scenarios the intervention helps prevent AMOC weakening while in others it accelerates vulnerability. The study is described as a proof of concept and the researcher stresses that geoengineering should not distract from the primary task of reducing greenhouse gas emissions.

The AMOC transports warm salty water northward at the ocean surface, which cools and sinks in the North Atlantic before returning south at depth, playing a critical role in distributing heat around the globe. Melting ice sheets from climate change alter ocean temperature and salinity in ways that can disrupt this circulation. Researcher Jelle Soons simulated multiple initial ocean states because no single climate model perfectly represents reality, finding that outcomes varied significantly across scenarios. In some, closing the strait stabilised the AMOC even as CO2 levels rose; in others, the circulation became more vulnerable.

The Bering Strait is approximately 80 kilometres wide and located in a remote area with no road access, making construction logistically and economically unprecedented. The strait is also an important migration route for marine mammals, and changes in current patterns and salinity would alter entire Arctic ecosystems. Timing emerges as a critical factor: if the intervention is implemented before the AMOC weakens significantly, it may provide support, but if the circulation has already deteriorated, the dam could have an adverse effect. These uncertainties make practical deployment highly speculative.

Soons places the research in the context of geoengineering more broadly, alongside stratospheric aerosol injection and large-scale carbon capture. The study raises governance questions about who would decide to close a sea passage between Russia and the United States, who would bear ecological consequences and whether a backup plan could reduce pressure to cut emissions. Soons frames geoengineering as a last resort rather than an alternative to climate policy, analogous to surgery that is preferable to avoid but sometimes necessary when other approaches have failed.

Key figure — 80 kilometres wide — the width of the Bering Strait