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LESSON 4 Overview of Earths Heat- Trapping Gases

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http://9-4fordham.wikispaces.com/Electro+Magnetic+Spectrum+and+light Electromagnetic Spectrum

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Earths Magnetosphere

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http://www.grc.nasa.gov/WWW/k-12/airplane/atmosphere.html The Earths Atmosphere (60 miles thick)

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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 Suns Emission Spectrum able to penetrate Earths atmosphere

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Being light, infrared travels through space at the speed of light. Matter is not space and the Earths 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. What does this penetrating energy do to Earth? http://www.windows2universe.org/physical_science/chemistry/molecules_vibrate.html

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http://www.agci.org/classroom/atmosphere/index.php Earths atmosphere

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http://www.globalchange.umich.edu/globalchange1/current/lectures/Perry_Samson_lectures/evolution_atm/index.html CONSTITUENTCHEMICAL SYMBOL MOLE %BONDING NitrogenN2N2 78.0841 triple OxygenO2O2 20.9471 double ArgonAr 0.934- Carbon DioxideCO 2 0.0352 double NeonNe 0.00182- HeliumHe 0.00052- MethaneCH 4 0.000174 single KryptonKr 0.00011- HydrogenH2H2 0.000051 single Nitrous OxideN2ON2O 0.000032 bonds (1 triple, 1 single) XenonXe 0.00001- OzoneO3O3 trace to 0.000802 single 99% 1% Earths Atmospheric Composition

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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 What is a Heat-Trapping Gas?

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http://www.elmhurst.edu/~chm/vchembook/images/irgreengas.JPEG 2500 nm 3330 nm 5000 nm 10000 nm 1000000 nm

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http://www.elmhurst.edu/~chm/vchembook/images/irwater.JPEG

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http://www.elmhurst.edu/~chm/vchembook/images/irmethane.JPEG

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http://www.elmhurst.edu/~chm/vchembook/images/irN2O.JPEG

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http://en.wikipedia.org/wiki/File:Atmospheric.transmittance.IR.jpg Greenhouse gas ABSORBANCE (in white)

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Effect of Heat-Trapping Gases http://mrsdlovesscience.com/greenhouse/greenhouse.htm l

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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).NOAACDIACNOAA

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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/

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Simplified Example of a Combustion Reaction