Using Olivine to Trap Carbon Dioxide

Many minerals absorb carbon dioxide from the atmosphere when they weather in the open. One that absorbs a lot is olivine, which is rich in magnesium. Expose it to air and it reacts with CO2 to form magnesium carbonate. So scientists have naturally wondered if we could dig up lots of olivine and use it to help solve our greenhouse gas problems. Recent studies show that it does work, but even when ground to powder a kilogram of olivine only absorbs a kilogram of carbon dioxide. So we could probably never mine enough to keep up. Still, "enhanced weathering" may turn out to be one part of a comprehensive program that might have a real impact on CO2 levels and thus on the future climate.