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Published byHayley Linsley Modified over 10 years ago
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The Greenhouse Effect
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Earth gases in the atmosphere
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The sun emits ultraviolet (UV) radiation which hits the earth
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These rays of light hit the earth and reflect back towards space in the form of UV as well as Infrared (IR) radiation
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gases in the atmosphere pick up some of the heat from the IR rays and disperse them back into the earths atmosphere keeping the earth warm enough to sustain life
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Would you be able to feel the heat?
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When certain gases in the atmosphere absorb IR Radiation their vibrational modes are excited and vibrate, causing them to collide with other molecules and transfer energy On a molecular level…
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When the electrons return to their ground state, they re-emit the energy with a frequency equal to the frequency of energy gap between the two levels
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Only certain gases do this, just like dogs can hear frequencies that humans cannot because their eardrum vibrates with different wavelengths than ours
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If this didnt happen… The climate would be an average of 60°F colder and the earth could not sustain life as we know it.
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So greenhouse gases are called greenhouse gases because they keep some heat in the atmosphere to sustain life on earth as a greenhouse does to sustain life in the greenhouse when it is cold outside
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So a round of applause for greenhouse gases !
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Lets find out which atmospheric gases are green house gases
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Greenhouse gas molecules are able to vibrate with the absorption of heat Hint…
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So why do greenhouse gases have such a bad reputation?
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Natural Versus Enhanced Climate chemists believe that humans are producing more of the naturally occurring greenhouse gases than the atmosphere can naturally handle from…
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Anthropogenic
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The most abundant atmospheric gas, Nitrogen molecules have a strong bond which makes it chemically stable and non-reactive in most circumstances. Nitrogen's simple structure is unable to absorb either visible or infrared light. As a result, nitrogen is not a greenhouse gas.
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Oxygen is the second most abundant atmospheric gas. Why do you think that Oxygen is also not a greenhouse gas?
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there are others
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Some greenhouse gases are not naturally occurring – they are manmade Sulfur Hexafluoride Carbon tetrafluoride Hexafluoroethane
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And Hydrofluorocarbons Which once saved the earth!
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CFCs or Chlorofluorocarbons
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UV light in the atmosphere would break thte bonds of the Chlorine in the CFCs and release it. Chlorine was found to deplete the ozone.
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HFC – Hydrofluorocarbons was the answer
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Right now HFCs do not contribute to climate change as much as CO2 but…
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Maybe we should just tell those people in China, India and Africa that they cant have what we have?
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Chemists to the rescue!
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Why should I care??????
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