A new study is exploring a radical idea: building a dam across the Bering Strait. The goal is to try to stabilize a massive ocean current, which helps regulate the planet's climate and is already slowing down. CBC science reporter Nicole Mortillaro walks us through what's happening to the system, why scientists are concerned, and what a slowdown could mean for rising sea levels to shifting weather and where people can live. Then, climate researcher Jelle Soons explains the thinking behind the dam. It's a proof of concept, not a real-world plan, and one that comes with significant risks and unknowns.