1. THE ATMOSPHERE OF THE EARTH
Components
Molecular Variation
Pressure Variation
Energy Balance
Temperature Variation
Layers

2. Components of the Atmosphere
Through all the layers, the composition of the atmosphere is about the same.
Each component has important uses and roles for our planet.
Each component cycles in and out of the atmosphere.

3. Atmospheric Components Cycle through the Atmosphere
Nitrogen cycles through
the atmosphere.
Carbon, oxygen, and carbon
dioxide cycle through the
atmosphere.

4. Molecular Variations in the Atmosphere

5. ATMOSPHERIC PRESSURE
Because of gravity, most of the molecules that make up the gasses of the atmosphere collect at the lowest levels.
Half of the molecules in the atmosphere exist below the 5 km level.
Weather occurs at levels below 10 km.

6. ENERGY BALANCE Incoming Energy Outgoing Energy
Energy is radiated from the earth at
the same rate that it is received. If not,
the earth would be getting hotter and
hotter.
The upper atmosphere is warmed by
the sun, so it is hotter as the altitude
increases.
The lower atmosphere is heated by
energy being radiated from the earth’s
surface, so that as the altitude
increases, the temperature decreases.
Incoming Energy Outgoing Energy

7. ATMOSPHERIC TEMPERATURE
Notice that temperature follows several patterns in the atmosphere.
The upper atmosphere is warmed by the sun, so it is hotter as the altitude increases.
The lower atmosphere is heated by energy being radiated from the earth’s surface, so that as the altitude increases, the temperature decreases.

8. ATMOSPHERIC LAYERS: TROPOSPHERE
This is the lowest layer of the atmosphere and the layer in which you live.
Almost all weather takes place in the troposphere.
The troposphere is heated by energy being radiated from the earth’s surface, so that as the altitude increases, the temperature decreases.
Most of the molecules of the atmosphere are found in the troposphere.

9. ATMOSPHERIC LAYERS: STRATOSPHERE
The stratosphere is the layer in which jets most often travel.
It is clear (clouds are found in the troposphere) and cold.
The ozone layer is found in the stratosphere. The warming that occurs in the upper part of the stratosphere happens because cosmic rays are absorbed by ozone, adding energy (heat) and making chemical changes.
Pollution in this layer does not migrate or mix.

10. ATMOSPHERIC LAYERS: MESOSPHERE
The mesosphere and stratosphere both contain a special form of oxygen called ozone.
Ozone filters out powerful ultraviolet rays from the sun, without which, life would be difficult on our planet.
This zone has the coldest temperatures in the atmosphere.

11. ATMOSPHERIC LAYERS: THERMOSPHERE
Temperatures rise rapidly in the thermosphere because high energy x-rays are being absorbed.
The thermosphere extends as high as 600 km, and temperatures can go as high as 2000 F.
The high temperatures found at this level would not really cause an object to get hot, because there is really on one ten millionth of the density of air as at the earth’s surface.

12. LAYERS OF THE ATMOSPHERE: IONOSPHERE and MAGNETOSPHERE

13. Layers of the Atmosphere: Ionophere and Magnetosphere
The ionosphere is named for the ions it contains. These are charged particles that result from powerful cosmic rays that collide with the atoms of the atmosphere. High energy particles strip electrons from the atoms of oxygen and nitrogen.
The ionosphere is important for long-distance radio communications by
reflecting radio signals. By repeated bouncing, a radio signal can travel
completely around the globe.
An aurora is triggered by the solar wind, a stream of charged particles
that come from the sun. The earth’s magnetic field deflects the solar wind
and as a consequence form the teardrop shaped zone known as the
magnetosphere.
The interaction between solar wind and magnetosphere produces the
Northern lights. Nitrogen ions produce pink and magenta light whereas
charged oxygen ions emit greenish light.