Part 3: Exceptional new findings show the huge potential of salt marshes for sucking up carbon. But is it too late for blue carbon to save the world?
When the ambitious plan to allow sea water to flood over the Steart peninsula in Somerset was completed in 2014, critics called it a waste of money. Floods had recently blighted the nearby area, and some local people argued the £20m spent on creating a new 250-hectare (617-acre) salt marsh would have been better spent on other flood-prevention projects.
Seven years ago, the concept of “blue carbon” – how marine ecosystems store carbon – was in its infancy. Some research had looked at how mangrove forests absorb carbon, but little was known about how effective seagrass and salt marshes also were at absorbing greenhouse gas emissions.