Carbon Dioxide and Forest Growth

Plants require carbon dioxide (CO2) for growth. How are they affected by the rise in atmospheric CO2 that occurred over the last century, as a result of human activities such as the burning of fossil fuels? Do plants use more CO2 (i.e, grow faster) when more CO2 is available?

There is some evidence that they may. A study of 55 forest plots in the Eastern United States reveals that the tree biomass is increasing at a faster rate now than in several decades past. After factoring out other known factors, the most likely causes appear to be increases in atmospheric CO2 and in temperature. This may be good news, for it means that as the atmospheric CO2 rises, some of the excess CO2 may naturally be stored in Earth's forest biomass. This could be slowing the rate of rise of CO2 (and global warming) that would otherwise occur.