Layers of the Atmosphere
Exosphere
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Above the Thermosphere
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Extends from about 375 miles (600 km) to 6,200 miles (10,000 km) above Earth's
surface.
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Molecules escape from our atmosphere at this level.
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Layer with the lowest density.
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Most satellites orbit here.
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Not a major layer of the atmosphere.
Thermosphere
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Above the Mesosphere and known as the upper atmosphere.
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Extends from about 53 miles (85 km) to 375 miles (600 km) from Earth's surface.
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Less dense than the Mesosphere.
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Energy and radiation from the sun heat up the gas molecules causing increasing
temperature with increasing height.
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Temperatures range from -184°F to 3,600 °F increasing with height.
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High temperature indicates the amount of energy absorbed by gas molecules.
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Still feels cold because there are not enough molecules to heat our skin.
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Also contains a layer called the Ionosphere.
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~37-190 miles from Earth's surface
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~Ionized gas particles float here, which help transmit radio waves.
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Aurora Borealis is here.
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Top of the layer is called the Thermopause.
Mesosphere
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Above the Stratosphere
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Extends from about 31 miles (50 km) to 53 miles (85 km) above Earth's surface.
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Temperature ranges from 5 °F to -184 °F decreasing with height
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Gas molecules thick enough to burn up meteorites coming into our atmosphere
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Less dense than the Stratosphere.
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Considered part of the middle atmosphere.
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Top of the layer is called the Mesopause
Stratosphere
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Above the Troposphere
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Extends to about 31 miles (50 km) from 4-12 miles (the tropopause) above
Earth's surface.
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Very clear and dry air (19% of atmosphere’s gases with little water vapor) supersonic jet plane travel possible.
Temperature increases with height (-60 °F to 5 °F)
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Contains the ozone layer (O3) - absorbs UV radiation.
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Less dense than the Troposphere
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Nacreous clouds present (super cooled clouds at poles)
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Considered part of the middle atmosphere.
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Top of the layer is called the Stratopause.
Troposphere
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Lowest layer = closest to Earth
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Extends 4-12 miles (6-20 km) high from Earth’s surface.
~higher at the equator; lower at the poles
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Temperature and density decreases with altitude
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Temperature ranges from 60 °F to -60 °F
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Contains 80 % of total mass of the atmosphere
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Weather, jet stream, and commercial flight takes place in this layer
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Top of the layer is called the Tropopause.