Why focus first on carbon dioxide?
Carbon dioxide is released in greater amounts and represents 50% of the warming attributed to greenhouse gases. As the major contributor of global warming, any serious environmental and economic program must first address this issue. The bulk of carbon dioxide comes from generating power and moving about in fossil fuel powered vehicles, the rest comes from agricultural and other activities. What are some of the other greenhouse gases? Some of the other greenhouse gases are methane, nitrous oxide, halocarbons, and sulfur hexafluoride. These and other greenhouse gases are indexed by their Global Warming Potential (GWP) so they can be expressed in carbon dioxide units. All greenhouse gases can be included in the carbon-trade market.
