In the first hundred years CO2 is absorbed into the upper ocean. The resulting
acidification limits further uptake by the upper ocean waters. During this time period, there is also typically some uptake by the land biosphere. In the next 900 years, the saturated upper ocean waters mix with the deep ocean, allowing further uptake. Eventually, the deep ocean acidifies as well, limiting further uptake. Over the next 10,000 years the ocean becomes buffered by dissolution of carbonate sediments and by carbonates washed in from land, reducing the acidity and allowing the ocean to take up additional carbon. Over longer time scales spanning more than 100,000 years, most of the remaining CO2 is removed by reacting with silicate minerals to form carbonates (e.g., limestone). NRC 2010.