Aim: How is our atmosphere structured? Do Now: Watch the video

Atmosphere : - the layers of gas that surrounding Earth.

I. Changes in Pressure - measured with a barometer (units = millibars) - Atmospheric pressure is the weight of the air molecules above you.

ESRT Page 13 Convert the following pressures: 1) inches Hg = ________ mb 2) mb = ________ inches Hg 3) inches Hg = __________ mb

- The atmosphere thins as you travel away from Earth’s surface. (less molecules) Where would you expect to find the most pressure? Where would you expect to find the least pressure? At sea level (1 atm) On a mountain peak -At sea level, there is 1 atm of pressure. (this is all the gas molecules are above your head weighing down on you) WHY?

-Pressure is highest at sea level = 1.0 atm. -As altitude increases air pressure decreases. -At the top of the Stratosphere the pressure comes close to 0 atm. Why does the pressure approach zero as altitude increases? - A decrease in gas molecules ESRT page 14 Sea level

II. Changes in Temperature: -a measure of the average kinetic energy in a substance. (particle movement) - Units include; Celsius Fahrenheit Kelvin ESRT p. 13 Convert the following temperatures: 1)50 0 F = ______ 0 C or _______ K 2)60 0 C = ______ 0 F or _______ K

- Changes in temperatures help indicate the different layers of the atmosphere. ESRT page 14 Describe the temperature change with altitude in the: Troposphere: Stratosphere: DIRECT INDIRECT

III. Layers of the Atmosphere

* Between each layer is a boundary that separates the layers called a “pause”. What features do you notice take place in the different layers of the atmosphere?

1.Troposphere: (where we live!) –90% of all gases –all clouds and weather –Temp. decreases as altitude increases What is the lowest temperature in the Troposphere? C Describe the relationship between temperature and altitude in the Troposphere.

2. Stratosphere: –Contains the Ozone Layer (blocks dangerous ultraviolet radiation). –Temperature increases as altitude increases. What is the highest temperature in the stratosphere? - 00C- 00C Describe the relationship between temperature and altitude in the Stratosphere.

–Contains Jet Streams; which are high speed winds that influence our daily weather.

3. Mesosphere –Meteoroids burn up due to friction with air particles forming “shooting stars”. –Temp. decreases as altitude increases. At what altitude does the Mesosphere begin? - 30mi or 50km Describe the relationship between temperature and altitude in the Mespsphere.

4. Thermosphere –Temperature increases as altitude increases. –Contains the ionosphere (charged particles) creating the “Aurora’s” or The Northern & Southern Lights Describe the relationship between temperature and altitude in the Thermosphere.

Aurora (Northern Lights)

Contains Earth’s Satellites Last layer before space

ESRT page 14

Closure: Complete the “Layers of the Atmosphere” worksheet by first filling in the names of each layer on the diagram. To help you, between Earth and the first line should be labeled the Troposphere. After filling in each layers name, write/draw all the information about each layer that we discussed in class for each layer. You may use your IPad to find further information about each layer and what might exists there. There are colored pencils in the back for you to use as well.