1. A IR P RESSURE N OTES 7 th Grade

2. A TMOSPHERE Is a mixture of gases that surrounds the Earth. What are some unique characteristics you can think of about our atmosphere? The two main components of our atmosphere are oxygen and nitrogen. The remaining one percent is made up of argon, carbon dioxide, water vapor, and other gases. At sea level there is 15 lbs of pressure per square inch of surface area

3. A TMOSPHERE C ONT ….. Three questions to answer How is air pressure produced here on Earth? Where is there greater air pressure at sea level or in the mountains? Do you think air temperature affected by the atmosphere? Explain?

4. F OUR LAYERS OF THE ATMOSPHERE Troposphere: The lowest layer of the Earth’s atmosphere and also the densest. This is where all of our weather occurs. Temp. varies Stratosphere: This part of the atmosphere is very thin and contains little moisture. Most of this layer is concentrated in the ozone layer. Temp. rises as altitude increases. Mesosphere: This is the coldest layer (as cold as -93 degrees Celsius) Temp. decreases as altitude increases. Thermosphere: The uppermost layer. Temp. increases with altitude. This is where a lot of the high energy solar radiation is absorbed.