CO2 - Our Carbon Climate!
In any given year, tens of billions of tons of carbon move between the atmosphere, hydrosphere, and geosphere. Human activities add about 5.5 billion tons per year of carbon dioxide to the atmosphere. The illustration above shows total amounts of stored carbon in black, and annual carbon fluxes in purple. (Illustration courtesy NASA Earth Science Enterprise)
Casual conversation about the weather on the moon would not be nearly as interesting as conversation about the weather here on earth. "Moon talk" would focus on temperatures either being really hot (200-186; F) or really cold (-200-186; F) with no in-between-the reason being that the moon doesn't have an atmosphere. Without a protective sphere of gas, the surface of the moon receives either the full force of the sun's energy and radiation or the total lack thereof. On earth however, we live at the bottom of a gigantic sea of gas. This invisible envelope holds in heat, reflects harmful solar radiation and contains life-giving compounds like carbon dioxide and oxygen.
Ninety-nine percent (by volume) of earth's atmosphere consists of the two main gases: nitrogen (about 78 percent) and oxygen (about 21 percent). Both gases play roles in the numerous complex biogeochemical cycles that support life on the planet, but they play almost no direct role in regulating the climate. For climate, it is the remaining 1 percent of "trace" gases that are most important. These trace gases include water vapor, ozone, and what are known as "the greenhouse gases"-carbon dioxide, nitrous oxide, methane, and chlorofluorocarbons (CFCs).