We use electricity generated by power plants that consume coal, natural gas, or oil. We burn wood, charcoal, natural gas, and coal to cook or keep warm. All these activities add carbon dioxide to the atmosphere. This gas traps heat from the sun. We also add other heat-trapping greenhouse gases to the atmosphere.
Nitrous oxide is added from nitrogen fertilizers used in agriculture.
Methane is emitted by rice paddies and cattle feedlots. CFC's not only trap heat but also destroy earth's stratospheric ozone layer. This is due, in part, to the growing number of people on earth, along with the growth of energy use, industrial activity, and agriculture. According to the Washington-based Environmental Protection Agency, humans presently spew six billion tons of carbon dioxide and other greenhouse gases into the atmosphere each year. Scientists are generally quite confident about two things.