This lesson was created by Jerry, a student in the UniTY Program at the Miami Museum of Science.

The ATMOSPHERE is a protective cover of air blanketing our Earth. It has five layers:

 

 EXOSPHERE: This is the outermost layer which stretches to 5,500 miles from the Earth. The air is very thin because the air particles are widely separated. Beyond the Exosphere lies outer space, where there are almost no air particles. There is no weather in the Exosphere.

 EXOSPHERE:

 

 

THERMOSPHERE: Once called the Ionosphere, this layer extends beyond the Mesosphere (our next layer) to the beginnings of outer space found in the Exosphere. Here solar energy boosts the temperatures to a maximum of 3,600 degrees Fahrenheit. It extends 250 miles beyond the Mesosphere.

 THERMOSPHERE:

 

 

 
 MESOSPHERE: The next layer extends upwards from the Stratosphere (our next layer) a distance of about 20 miles, to about 50 miles above sea level. The air there is thinner because the air particles are farther apart, so it very hard to breathe. The temperature decreases greatly, as low as 255 degrees Fahrenheit, and ice crystals can form.
 

MESOSPHERE:

 

 

 STRATOSPHERE: For the next 30 miles, there is basically no weather. Jet pilots fly there to avoid storms.

 

 

STRATOSPHERE:

 

 

 TROPOSPHERE: This is the layer nearest the earth. It ranges from 5 to 11 miles in thickness. All of our weather takes place within this layer.

 TROPOSPHERE:

 



Click here for a complete picture of the five layers of the atmosphere


Air has weight and presses down on the Earth. At sea, there is about 15 pounds of pressure on every square inch (psi) of each person, place, and thing. You can not feel the weight of the air pressing on your body because it's balanced by the same amount of pressure inside your body. The higher you climb, the less air pressure there is. The highest mountain peak has only 5 pounds of pressure per square inch. Also, an easy way to remember is that cold air sinks and hot air rises.

Weather is the daily condition of the Troposphere in a particular place. What we call weather is air temperature, air pressure, air movement, and the moisture level in the air. Although air pressure is about 15 pounds per square inch at sea, it does vary somewhat as the weather changes. We say that cold air is heavier then warm air, because cold air is much more dense. We say the air pressure is "low" when the air particles are farther apart and the air is lighter. This is usually true when air is warm.



HAVE NO FEAR OF THE ATMOSPHERE

Test your memory

  1. In which layer of the Atmosphere do jet pilots fly?
  2. How many layers of Atmosphere does the Earth have?
  3. What is the layer nearest the Earth?
  4. What is the layer nearest to outer space?
  5. If Cold air sinks, then what does hot air do?


Click here to see the answers

 

If you want to learn more about the atmospheric world around you, just scroll down, pick a link, and click.


Try the following link for more information about the Atmosphere.

 

To learn how the Atmosphere started click here.

 

Learn about Mars's Atmosphere.

 

Click here to learn the structure of the Atmosphere.

 

To learn more about hurricanes in our Atmosphere , click here.


Visit "Science in the Stratosphere". This is the daily journal of two educators as they visit the NASA Ames Research Center and fly with astronomers on two research missions aboard the Kuiper Airborne Observatory.
http://marple.as.utexas.edu/~WebSci/journals.html

 

Explore THE PRIMARY CIRCULATION of the Earth

http://www.eastnc.coastalnet.com/weather/nwsmhx/air.htm

 

Investigate facts about The Earth's Atmosphere

http://www.aspire.cs.uah.edu/~jonesj/r.html

 

Special thanks to:

 

 

 &

 

 Unisys Corporation
  

Museum of Science