Carbon dioxide (CO2) is a molecule consisting of one atom of carbon and 2 atoms of oxygen. When we breathe, we exhale CO2. It is a natural component in the atmosphere, and acts as a greenhouse gas—allowing solar radiation to pass through but keeping long-wave (heat) radiation from escaping. Without this, Earth would be a cold, lifeless planet. However, it becomes problematic when things are out of balance: too much CO2 in the atmosphere traps more and more heat, leading to global climate change.
Since the industrial revolution, CO2 concentrations in the atmosphere increased by nearly 100 ppm to 379 ppm by 2005. Anthropogenic (human) emissions have increased dramatically during that time. In 2004, CO2 produced by burning fossil fuels accounted for 56.6% of all the greenhouse gases emitted by human activities—about 7 billion tons of carbon per year! During the last 100 years, the average global temperature has increased by about 1 °F at the equator and 5 °F at the poles. By taking carbon that was stored in a geologic pool of the carbon cycle and releasing it as CO2 into the atmospheric pool, it is likely that humans have tipped the balance toward global warming.
To stabilize CO2 output, a number of technologies are being investigated. Industrial complexes and power plants are major emitters. Research is focused on finding ways to capture the CO2 and keep it from being released into the atmosphere by injecting it into deep underground reservoirs. This is known as Geologic carbon storage.
IPCC Fourth Assessment Report
NETL Reference Shelf
Energy Information Administration
ZERT is funded by the United States Department of Energy, under Award No. DE-FC26-04NT42262. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the author(s) and do not necessarily reflect the views of the DOE.
© 2005 Montana State University