Will sinking tonnes of wood into the ocean help tackle climate change?

More than 10,000 tonnes of waste wood have been sunk into the Atlantic Ocean in an effort to remove carbon dioxide from the atmosphere. The US-based company behind the effort, Running Tide, says the carbon within the wood, which would otherwise have been burned, won’t be circulated out of the deep ocean for hundreds or even millions of years.

This effort is the largest yet among a growing slate of start-ups aiming to lock up CO2 on the seafloor from the …