1. Our Atmosphere Our atmosphere helps us in two very important ways. –It acts as a blanket by holding in the amount of heat needed to keep earth livable. –It affects the amount of solar energy that reaches earth & protects it from the sun’s harmful radiation.

2. Our Atmosphere The four gases that make up our atmosphere include... –Nitrogen –Oxygen –Carbon dioxide –Water vapor –Trace amounts of other gases

3. Our Atmosphere The gases that we consider to be “greenhouse gases” are... –Water vapor –Carbon dioxide

4. GRAVITY!!! The force that keeps earth’s atmosphere where it’s supposed to be!

5. The Layers of Our Atmosphere The Troposphere –The place where most of earth’s weather happens. –Most of the water vapor is located in the troposphere. –The higher you go, the colder the temperature in this layer.

6. The Layers of Our Atmosphere The Stratosphere –The second layer of our atmosphere. –The stratosphere protects earth from the sun’s harmful radiation. –Temperature is fairly constant here. –The ozone layer is found in the stratosphere.

7. The Layers of Our Atmosphere The Mesosphere –The middle or third layer of our atmosphere.

8. The Layers of Our Atmosphere The Exosphere & Thermosphere –These are the layers where satellites and other spacecraft can travel. –In the Exosphere earth’s atmosphere fades into the vacuum of outer space.