The level of CO 2 in the atmosphere was 190 parts per million at the end of the last ice age 20,000 years ago, and rose to 280 parts per million by the start of the industrial revolution. Now it is 370 parts per million, which is higher than any time in at least 400,000 years. The burning of fossil fuels currently produces six billion metric tons of carbon per year. While some of that emission is absorbed by the oceans and the world's forests, three to four billion tons accumulate in the atmosphere each year. That results in the concentration rising at a rate of between 1 and 2 parts per million per year.
Water has a natural capacity to dissolve carbon dioxide.
One aspect of the Carbon Mitigation Initiative is to understand how quickly the gas would leak from such storage locations. Slow leakage, on the order of thousands of years, would allow natural processes to absorb the carbon in a safe manner. The terrestrial biosphere might be induced to store an additional 50 to 100 billion tons of carbon, in part through reforestation efforts. CMI scientists will study the chemical, physical and biological changes that added CO 2 would cause over time. Researcher will also study what kinds of monitoring will be needed to ensure public safety.