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Overview of Earth’s Heat-Trapping Gases. Lesson 4. Electromagnetic Spectrum. http://9-4fordham.wikispaces.com/Electro+Magnetic+Spectrum+and+light. Earth’s Magnetosphere . The Earth’s Atmosphere (60 miles thick). http://www.grc.nasa.gov/WWW/k-12/airplane/atmosphere.html.
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Electromagnetic Spectrum http://9-4fordham.wikispaces.com/Electro+Magnetic+Spectrum+and+light
The Earth’s Atmosphere (60 miles thick) http://www.grc.nasa.gov/WWW/k-12/airplane/atmosphere.html
Sun’s Emission Spectrum able to penetrate Earth’s atmosphere The blue line indicates the approximate intensity of radiation that penetrates Earth's atmosphere at wavelengths from the ultraviolet (UV) through the visible to the infrared. Light at low UVC wavelengths is completely absorbed by the atmospheric ozone layer, so organisms on Earth have developed no tolerance to it. http://www.nature.com/nature/journal/v441/n7091/fig_tab/441299a_F1.html
What does this penetrating energy do to Earth? Being light, infrared travels through space at the speed of light. Matter is not space and the Earth’s atmosphere is obviously matter. Heat is a property of matter. The rate of transmission is slowed as this energy enters the atmosphere. Work is thereby done; so heat is created. Some atmospheric molecules are more sensitive to this energy than others based on their molecular shape and bonds. http://www.windows2universe.org/physical_science/chemistry/molecules_vibrate.html
Earth’s atmosphere http://www.agci.org/classroom/atmosphere/index.php
Earth’s Atmospheric Composition 99% 1% http://www.globalchange.umich.edu/globalchange1/current/lectures/Perry_Samson_lectures/evolution_atm/index.html
What is a “Heat-Trapping Gas”? Objects that absorb all radiation incident upon them are called "blackbody" absorbers. The earth is close to being a black body absorber. Gases, on the other hand, are selective in their absorption characteristics. While many gases do not absorb radiation at all some selectively absorb only at certain wavelengths of energy. Those gases that are "selective absorbers" of solar energy are the gases we know as “heat-trapping gases”. http://www.globalchange.umich.edu/globalchange1/current/lectures/Perry_Samson_lectures/evolution_atm/index.html
2500 nm 3330 nm 5000 nm 10000 nm 1000000 nm http://www.elmhurst.edu/~chm/vchembook/images/irgreengas.JPEG
http://www.elmhurst.edu/~chm/vchembook/images/irmethane.JPEG
Greenhouse gas ABSORBANCE (in white) http://en.wikipedia.org/wiki/File:Atmospheric.transmittance.IR.jpg
Effect of Heat-Trapping Gases http://mrsdlovesscience.com/greenhouse/greenhouse.html
CO2 levels (parts per million) over the past 10,000 years. Blue line from Taylor Dome ice cores (NOAA). Green line from Law Dome ice core (CDIAC). Red line from direct measurements at Mauna Loa, Hawaii (NOAA).
This Is What Worries Many Scientists 0 http://www.realclimate.org/index.php/archives/2004/12/temperaturevariations-in-past-centuries-and-the-so-called-hockey-stick/