ENVIRSC 1A03 Lecture : Greenhosue effect notes.docx
13 Oct 2013
School
Department
Course
Professor
Document Summary
If fossil fuels burn completely, the end products are carbon dioxide and water. Today the carbon dioxide is a waste product, one that goes into the air adding to global warming; or the oceans acidifying them; or underground with as yet unknown consequences. These gases, called greenhouse gases, include carbon dioxide, methane, nitrous oxide, chlorofluorocarbons (cfcs), and the ozone in the lower atmosphere. There is a natural balance between the energy coming into our atmosphere from the sun and the energy escaping from the earth back into space. A simplified description of this energy balance depicts the energy that comes in as relatively short wavelength uv radiation and the energy that goes out as longer wavelength ir radiation. Much of the high-energy radiant energy from the sun is absorbed in the upper atmosphere, but some of the ultraviolet radiant energy passes through. The lower-energy end of the ultraviolet portion of the light spectrum reaches the earths surface and warms it.
