This animation explores how carbon enters the atmosphere and can be removed through a series of chemical reactions.

Carbon naturally cycles between the atmosphere, land, and ocean. The animation follows one common path of carbon through different forms and locations. As shown, carbon can enter the atmosphere as carbon dioxide from volcanic eruptions. Carbon dioxide can be removed from the atmosphere by dissolving in water to form carbonic acid, which is carried to the ground in rainwater. Carbonic acid can react with rocks through weathering and ultimately produces calcium carbonate in the ocean, also known as limestone or chalk.

This animation is a clip from a 2012 Holiday Lecture Series, Changing Planet: Past, Present, Future. Depending on students’ background, it may be helpful to pause the animation at various points to discuss different parts of the carbon cycle.