By: Brian C. Bradshaw

Layers of the Atmosphere  Exosphere  Thermosphere  Mesosphere  Stratosphere  Troposphere  Exosphere  Thermosphere  Mesosphere  Stratosphere  Troposphere

Troposphere  Starts at earth’s surface and goes 8 to 14.5 kilometers (5-9 miles)  Most dense  As you go higher, temperature drops about 17 to 52 degrees Celsius  Almost all weather is found in this region  Also known as the lower atmosphere  Starts at earth’s surface and goes 8 to 14.5 kilometers (5-9 miles)  Most dense  As you go higher, temperature drops about 17 to 52 degrees Celsius  Almost all weather is found in this region  Also known as the lower atmosphere

Stratosphere  Starts above troposphere and goes 50 kilometers  Dry and less dense than troposphere  Temperature increases gradually to -3 degrees Celsius, due to absorption of ultraviolet radiation  Ozone is in this layer, it absorbs and scatters the solar ultraviolet radiation  99% of “air” is located in the troposphere and stratosphere  Stratopause separates troposphere and stratosphere  Starts above troposphere and goes 50 kilometers  Dry and less dense than troposphere  Temperature increases gradually to -3 degrees Celsius, due to absorption of ultraviolet radiation  Ozone is in this layer, it absorbs and scatters the solar ultraviolet radiation  99% of “air” is located in the troposphere and stratosphere  Stratopause separates troposphere and stratosphere

Mesosphere  Starts just above the stratosphere and continues for 85 kilometers (53 miles)  Temperatures fall as low as -93 degrees Celsius as you increase in altitude  Chemicals are in excited state as they absorb energy from the sun  Mesopause separates mesosphere from thermosphere  Stratosphere + Mesosphere = middle atmosphere  Starts just above the stratosphere and continues for 85 kilometers (53 miles)  Temperatures fall as low as -93 degrees Celsius as you increase in altitude  Chemicals are in excited state as they absorb energy from the sun  Mesopause separates mesosphere from thermosphere  Stratosphere + Mesosphere = middle atmosphere

Thermosphere  The thermosphere starts just above the mesosphere and extends to 600 kilometers (372 miles) high.  Temperatures can go as high as 1,727 degrees Celsius.  Chemical reactions occur much faster than on the earth’s surface  Also known as the upper atmosphere  The thermosphere starts just above the mesosphere and extends to 600 kilometers (372 miles) high.  Temperatures can go as high as 1,727 degrees Celsius.  Chemical reactions occur much faster than on the earth’s surface  Also known as the upper atmosphere

Exosphere  This is beyond the atmosphere  Starts at the top of the thermosphere and continues until it merges with the interplanetary gases, or space.  In this region of the atmosphere, Hydrogen and Helium are the prime components and are only present at extremely low densities.  This is beyond the atmosphere  Starts at the top of the thermosphere and continues until it merges with the interplanetary gases, or space.  In this region of the atmosphere, Hydrogen and Helium are the prime components and are only present at extremely low densities.