INTRO Objective 02/4/2013 Identify the layers of the atmosphere. What causes your ears to pop as you drive up a mountain? What does altitude have to do with air-pressure?

LAYERS OF THE ATMOSPHERE

Layers of the Atmosphere  Atmosphere  The mixture of gases that surrounds our planet, allowing plants and animals to live here.

Does Air Have Mass?  What makes up our Atmosphere?  A mixture of gases  Nitrogen – 78%  Oxygen – 21%  And other stuff:  Carbon dioxide  Salt  Dust  Ice  Water vapor

Does Air Have Mass?  Air pressure  The measure of the force with which air molecules push on a surface.  Pressure Demo

Does Air Have Mass?  What is Air Pressure?  At sea-level, air weighs about 30 pounds per square inch!  However, scientists measure air pressure in millibars (mb)

Layers of the Atmosphere  What separates the layers?  Areas of different temperature

Layers of the Atmosphere

 Troposphere  0 – 12km  Lowest layer  All weather and clouds occur here

Layers of the Atmosphere  Stratosphere  12 – 50km  Contains the Ozone Layer, which absorbs harmful UV rays from the sun  Planes fly here

Layers of the Atmosphere  Mesosphere  50 – 80km  Coldest layer  Meteors burn up here, producing “meteor tails”

Layers of the Atmosphere  Thermosphere  80 – 550km  No definite outer limit  Hottest layer, but thinnest

Layers of the Atmosphere  Thermosphere continued  Divided into two layers  Ionosphere Reflects radio waves back to earth Aurora Borealis occurs here  Exosphere Satellites and the International Space Station orbit in this layer!

Layers of the Atmosphere  Summary:  What are the four layers of the atmosphere?  Which layer of the atmosphere makes it possible to listen to the radio?  Which layer do you live in?

Objective 02/4/2013 Outro Identify the layers of the atmosphere. Why does the temperature of different layers of the atmosphere vary?