Enlarge / Bioreactors that host algae would be one option for carbon sequestration—as long as the carbon is stored somehow. (credit: Getty Images)
More than 200 kilometers off Norway’s coast in the North Sea sits the world’s first offshore carbon capture and storage project. Built in 1996, the Sleipner project strips carbon dioxide from natural gas—largely made up of methane—to make it marketable. But instead of releasing the CO2 into the atmosphere, the greenhouse gas is buried.
The effort stores around 1 million metric tons of CO2 per year—and is praised by many as a pioneering success in global attempts to cut greenhouse gas emissions.
Last year, total global CO2 emissions hit an all-time high of around 35.8 billion tons, or gigatons. At these levels, scientists estimate, we have roughly six years left before we emit so much CO2 that global warming will consistently exceed 1.5° Celsius above average preindustrial temperatures, an internationally agreed-upon limit. (Notably, the global average temperature for the past 12 months has exceeded this threshold.)
