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Arches National Park Geology Tour provides an extensive, visually rich description of the geology of Arches, by Deborah Ragland, Ph.D. See our DVD collection.

Movie courtesy of the Changing Climates project at Colorado State University.

Greenhouse Effect Movie - Scott Denning

In this movie, Professor Scott Denning of the Atmospheric Science Department at Colorado State University explains how greenhouse gases in Earth's atmosphere warm our planet. In this lively, animated presentation, Professor Denning first explains how visible light (a form of electromagnetic radiation) from the Sun delivers energy to Earth. Next, he describes how some of this energy is trapped in Earth's atmosphere by the greenhouse effect, which warms our planet. Molecules of greenhouse gases, especially water vapor and carbon dioxide, "recycle" some of the heat energy which would otherwise escape from Earth in the form of infrared radiation.

Most of the gas molecules in our atmosphere are nitrogen (N2) and oxygen (O2). Each of these types of molecules has just two atoms. This means these molecules can only vibrate in one way, and therefore aren't very good at absorbing energy. Carbon dioxide (CO2) and water vapor (H2O) molecules, on the other hand, have three atoms per molecule... so they can vibrate in various different ways. This makes them better at absorbing energy from infrared radiation... which is why they are such effective greenhouse gases.

Adding extra carbon dioxide to Earth's atmosphere increases the temperature of the atmosphere. Humans have added lots of CO2 to the atmosphere, mostly by burning fossil fuels such as oil, coal, and natural gas. This extra CO2 enhances the greenhouse effect and is the main cause of global warming.

Right-click (Windows) or Option-click (Mac) here to download a copy of this video in QuickTime format.

Last modified January 29, 2010 by Randy Russell.

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The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF