Environment: Removing carbon dioxide directly from the atmosphere could help combat climate change. Will it really work? Preventing catastrophic climate change, most people agree, will mean reducing the level of man-made carbon dioxide (CO2) in the atmosphere. That, in turn, will require the widespread use of “low carbon” technologies such as solar and wind power, more energy-efficient buildings, and so on. Some countries have pledged to reduce their greenhouse-gas emissions by 80% by 2050, and campaigners are calling for cuts of 90% or even 100%. New Zealand, Costa Rica and Norway are racing to become the world's first “carbon neutral” country. But some researchers think there might be a simpler way to reduce the level of CO2 in the atmosphere: to build “air capture” machines that, as their name suggests, grab it from the air.