• Changes in the Carbon Cycle 'Left unperturbed, the fast and slow carbon cycles maintain a relatively steady concentration of carbon in the atmosphere, land, plants, and ocean. But when anything changes the amount of carbon in one reservoir, the effect ripples through the others....'• Effects of Changing the Carbon Cycle 'It is significant that so much carbon dioxide stays in the atmosphere because CO2 is the most important gas for controlling Earth’s temperature. Carbon dioxide, methane, and halocarbons are greenhouse gases that absorb a wide range of energy—including infrared energy (heat) emitted by the Earth—and then re-emit it. The re-emitted energy travels out in all directions, but some returns to Earth, where it heats the surface. Without greenhouse gases, Earth would be a frozen -18 degrees Celsius (0 degrees Fahrenheit). With too many greenhouse gases, Earth would be like Venus, where the greenhouse atmosphere keeps temperatures around 400 degrees Celsius (750 Fahrenheit)....'• Studying the Carbon Cycle 'What will those changes look like? What will happen to plants as temperatures increase and climate changes? Will they remove more carbon from the atmosphere than they put back? Will they become less productive? How much extra carbon will melting permafrost put into the atmosphere, and how much will that amplify warming? Will ocean circulation or warming change the rate at which the ocean takes up carbon? Will ocean life become less productive? How much will the ocean acidify, and what effects will that have?....' (Original Source: NASA Earth Observatory)