EnvironmentProjects to remove carbon dioxide from the atmosphere by making the oceans less acidic are popping up all over the world New Scientist visited one in New York Citys East river 25 November 2024 New York Citys East river is polluted and contains higher than average levels of carbon dioxideEd Rooney/AlamyOn 14 November, I toured a shipping container bristling with tubes and wires, perched beside New York Citys East river. It is the test site of a start-up called Vycarb, which recently began adding crushed rocks and other chemicals to the water to remove carbon dioxide from the atmosphere.On one side of the container, an hourglass-like device mixed a fine stream of calcium carbonate mineral powder with water pumped from below. This alkaline, grey-green slurry was then released into an