FARGO — The general climate of our planet is controlled by the delicate energy balance between incoming radiation from the sun and outgoing radiation from Earth. Chemical and physical processes in the atmosphere are critical to this balance. Specifically, the presence of greenhouse gases such as water vapor, carbon dioxide and methane have the effect of letting most solar radiation pass through the air to the ground and reflecting some of the outbound terrestrial radiation back into the lower atmosphere.
Without this greenhouse effect, the average temperature around the world would be around 30 degrees below freezing, so the entire Earth would be frozen, and life would be very different if it existed at all. It stands to reason that, in the past as well as in the future, changes to the chemical makeup of the atmosphere, whether natural or caused by human activity, can affect this balance.