Energy from the sun drives the earth’s weather and climate. Incoming rays heat the earth’s surface, radiating energy back into space. Atmospheric “greenhouse” gases(water vapor, carbon dioxide, and other gases) trap some of the outgoing energy. Without this natural “greenhouse effect,” temperatures on the earth would be much lower than they are now, and life as we know it would be impossible. It is possible, however, to have too much of a good thing. Problems arise when the
concentration of greenhouse gases increases beyond normal levels, thus retaining excessive heat somewhat like a car with its windows closed in the summer.