Researchers have found that to limit global warming to 1.5 degrees, it may be necessary to remove 10 gigatons of carbon dioxide annually from the Earth's atmosphere and oceans. The key to success will be a diverse set of carbon dioxide removal methods. Diversification reduces risk. That's one of the key conclusions of a new study led by scientists at the Department of Energy's Pacific Northwest National Laboratory. An effective path to limiting global warming to 1.5 degrees Celsius by the end of this century is likely to require a combination of technologies that can remove carbon dioxide from the Earth's atmosphere and oceans.