Metric ton

One typical Grecian kiln engorged one thousand muleloads of juniper wood in a single burn. Fifty such kilns would devour six thousand metric tons of trees and brush annually.

Scientists and engineers are developing big machines to suck carbon dioxide out of the atmosphere, but the technology sucks up a lot of energy and money as well — as much as $1,000 per metric ton of captured CO₂. A team led by chemists at the University of California, Berkeley, has created a yellow powder that might boost this field by absorbing CO₂ much more efficiently.