Deep below the ocean surface, the light fades into a twilight zone where whales and fish migrate and dead algae and zooplankton rain down from above. This is the heart of the ocean’s carbon pump, part of the natural ocean processes that capture about a third of all human-produced carbon dioxide and sink it into the deep sea, where it remains for hundreds of years.
There may be ways to enhance these processes so the ocean pulls more carbon out of the atmosphere to help slow climate change. Yet little is known about the consequences.
