“Maine Startup Aims To Pull Carbon Out Of The Atmosphere By Growing — And Then Sinking — Kelp Farms”
I think that headline says it all – lots of details in the story from WBUR right here, notably the fact that the idea is to grow kelp on buoys out in the deep ocean; it grows from photosynthesis and when it gets too heavy, it pulls everything down to the ocean floor. Requires a market for carbon to work financially, of course.
The idea isn’t crazy, according to this research, but it won’t be easy to do at scale.