Our AtmosphereComposition of the AtmosphereThe layer of gases that surrounds our planet is called the atmosphere. The atmosphere is composed of 78% nitrogen, 21% oxygen and 1% other gases. Water vapor and tiny particles of dust, smoke and other chemicals are also found in the atmosphere.© Copyright NewPath Learning. All Rights Reserved. 94-4554Visit www.newpathlearning.com for Online Learning Resources.Importance of the AtmosphereThe Earth is unique because it has an atmosphere that can support life. Oxygen and gases in the air are necessary for survival. The atmosphere also traps the Sun’s energy to maintain moderate temperatures and forms a protective layer from the Sun’s radiation. Atmospheric PressureThe force that atmospheric gases exert on a surface is called air pressure, or atmospheric pressure. This pressure is highest near sea level because gravity pulls the air molecules close to the Earth’s surface. Pressure decreases as altitude increases.Air PollutionHumans add pollutants into the atmosphere every day. Natural sourcessmoke and volcanic ash. Air pollutants can travel great distances and impact environments around the globe.Earth’satmosphereSun’s energyprotective layertraps energyaltitudeincreasesmore pressureless pressurePhotos courtesy of USFWS, USGS, USDOT & USDOE.The layer of gases that surrounds our planet is called the atmosphere. The atmosphere is composed of 78% nitrogen, 21% oxygenand 1% other gases. Water vapor and tiny particles of dust, smoke and other chemicals are also found in the atmosphere.TTTTTTTTTTTTTThhhhhhhhhhhhhhhhheeeeee EEEEEEEEEEEEEEEaaaaaaaaaaarth is unnnnnnnnnnniiiiiiiqqqqqqqqqqqqquue bbbbbbbbbbbbbbeeeeeeeeeeeeeccccccccccccccaaaaaaaaaaaaauuuuuuuuuuuuuussssssssssssseee iiiiiiiiiitttttttttt hhhhhhhhhhhhaaaaaaaaaasssssssss aaaaaaaaaaaaaannnnnnnnnnnn atmmmmmmmmmmmmmmmmoooooooooooooosssssssssssppppppppppppppppppphhhhhhhhhhhhhhhhheeeeeeeeeere thatt can support liiiiifffffffffffffffeeeeeeeeeeeeee... OOOOOOOOxxxxxxxxxxxxxxyyyyyyyyyyyyyyyyyyyyyyygggggggggggggggeeeeeeeeeeennnnnnnnnnnnnn aaaaaaaaaaaannnnnnnnnnnnnndd ggggggggggggggggggaases in tttttttttttthhhhhhhhhhhhhhhhhhhhhhhhheeeeeeeeeee aiiiiiirrrrrrrrrrrrrr aaaaaaaaaaaaaarrrrrrrrrrrrreeeeeeeeeeeeee nnnnnnnnnnnnneeeeeeeeeeeccccccccccessary ffoooooooooooooorrrrrrrrrr surrrrvvvvvvvvvvvvviiiiiiiiiiiiiivvvvvvaaaaaaaaaallllllllllll...... TTTTTTTTTTTTTTTTTTTTTThhhhhhhhhhhhhhhhhhe atmosphere alllllllso trapssssssss tttttttttttthhhhhhhhhhhhhhhheeeeeeeeeeeee SSSSSSSSSSSSuuuuuuuuuuuuunnnnnnnnnnnnnn’s energy to maintain moddddddddddddeeeeeeeeeeeeerrrrrrrrrrrrrraaaaaaaaaaaattttttttte temperatures and ffoooorrrrrmmmmmmmmsssss aaaaa pppppppppprrrrrrrrooooooooootective layer from ttttttttttttthhhhhhhhhhhhhhhhhheeeeeeeee SSSSSSSSSuuuuuunnnnn’’sssssss rrrrrrrrraaaaddddddddddddiiiiiiiiiiiiiiiiiaaaaaaaaaaation. The force that atmospheric gasess eeeeeeeeeexxxxxxxxxxxxxeeeeeeeeeeerrrrrrrrrrttttttttt ooooooooooooooonnnnnnnnnnnnn aaaaaaaaaaaaa sssssssssssuuuuurface is called air pressure, or aaaaaaaaaaaaaattttttttttttmmmmmmmmmmmmmmoooooooosssssssssspppphhhhhhhhhericcccccccc pppppppppppppprrrrrrrrrrreeeeeeeeeeessssssssssssssssssssssssuuuuuuuuuuuuurrrrrrrrrreeeeeeeeeee. This pressure is highest nnnnnnnnnnnnnneeeeeeeeeeeeeeeaaaaaaaaaar sssseeeeeeeeeeeeeeaaaaaaaaaaaa llllllllllleeeeeeeeeeevelllll because gravity pulls the air molecuulllllllllleeeeeeeeeeeeeesssssssssssssss cccccccccclosssssseeeeeeeeeee ttttttttttttoooooooooooooo the Earth’s surface. Pressure deecccccccccccrrrrrrrrrrrrrreeeeeeeeeeeeaaaaaaaaaaaaaaaasssssssssseeees as allllllllllltttttttttttiiiiiiiiiiiiitttttttttttttuuuuuuuuuuuuuuuddddddddddde iiiiiiiiiiiiiinnnnnnnnnnnnncccccccccccrrrrrrrrrrreeeeeeeeases.Huuummmmmmmmmmmmmmmmmannnnnnnnnnnnsssss aaaaaaaaaaaaadddddddddddddddddddddddddddddddddddddd pppppppppooooooooooollllllllllllllllluuuuuttttttttttaaaaaaaaannnnnnnts intooooooooo ttttttttttttthhhhhhhhhhhhhhhhheeeeeeeeeeeeee attttttttttmmmmmmmmmmmmmmmmmmmoooooooooooooossppphereeeeeeeeee eeeeeeeeeeeeevvvvvvvvvvvvvvvveeeeeeeeeeeeeery day. Natural sourcessmmmmmmmmmmmmmmmmmooooookkkeeeeeeeeeeeeeeee aaaaaaaaaaaaaaaannnnnnnnnnnndddddddddddd vvvvvvvvvvvoooooooooolllllllllcccccccccccaaaaaaaaaaaannnnnnnnnnnniiiiiiiiiiiicccccccccc asssssssshhhhhhhhhhhhhhhhhhh....... AAAAAAAAAAAir polllllllllllllllluuuuuuuuuuuuuuttttttttttttttaaaaaaaaaaannnnnnnntttttttssssssssssssss cccccccccccccaaaaaaaaaaaaaannnnnn tttrrrrrrrrrrrrrraaaaaaaaaaaaavvvvvvel great distances and impact environments around the globe.Eaaaaaaaaarrrrrrrrrthhhhhhhhhh’’’’’’satmmmmmmmmoooooooooooospppppppppppphhhhhhhhhhhereSun’s energyprotective layelayergygyttrrrrrrraaaaaaaaaaaapps eeeeeeeeeennnnnnnnnnnnnneeeeeeerrrrrrrrrrrrggggggggyttttttttttttrrrrrrrrrrrraaaaaaltitudeincreasesommommoomereereereeerrsseeuup pressureressureppressrepressureless pressure
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