Study of the Atmosphere Meteorology

Atmosphere  Layers of gasses/tiny particles that surround Earth.

Meteorology  Study of the Atmosphere (Ex- Why is sky red?)

Weather  Condition of the atmosphere at a particular time and place  Temperature, air movements, moisture

Atmospheric Composition (pie chart)

Air Pressure Definition  Force of air on the surface of the earth  Can look at it 2 ways: AP = (# of air molecules) / (Area) AP = (# of air molecules) / (Area) AP = (# of collisions) / (Area) AP = (# of collisions) / (Area)

How can we show Air Pressure?

3 Ways to Change Air Pressure  Change Volume  Change # of molecules  Change Temperature

Barometer- Measures atmospheric pressure.

Mercurial Barometer  “Mercurial” comes from the fact that many used mercury as the liquid in the barometer  Air pressure pushes on liquid and squeezes it up a certain height (giving pressure)

Aneroid Barometer

Atmospheric Layers  Layers in sky based on different temperature (Usually defined by altitude).  There is not an exact change on a line between each layer, but more of a gradual shift.

Troposphere  Closest to Earth, where all weather occurs  Temperature drops by about 6.5 o C/km due to increase distance from heat absorbed by earth.  Top of this layer is Tropopause, where temp is constant

Stratosphere  Goes from top of troposphere to about 50 km.  Most of the Ozone (0 3 ) is here.  Temp increases due to absorption of sunlight by O 3 molecules.  Top is Stratopause where temp is constant

Mesosphere  Goes from top of Stratosphere to about 80km.  Temp starts to decrease again and this is the coldest layer (up to -90 o C).  Top is Mesopause

Thermosphere  Top of Mesosphere to outter space  Increase b/c N and O atoms absorb solar energy (like the O 3 in the Stratosphere)  Temp as much as 2000 o C

Ionosphere  km  Solar rays strike atoms in the layer, striping electrons causing them to become ions

Exosphere  550km-outer space (more than 1000km)

Solar Energy  All of the waves of energy that come from the sun (everything form EM Spectrum)

Electromagnetic Spectrum

Visible Wavelengths

Radiation  Energy from sun that travels to Earth as waves

Reflection vs Scattering

Scattering The shorter the wavelength, the more likely it is to be scattered. Longer wavelengths are more easily reflected.

HW  Why does the sky sometimes appear blue, othertimes red, and sometimes white?  Explain Each…

Why is sky Red during sunset?  Annimation Annimation  Youtube Video Youtube Video Youtube Video

Why does the sky appear white sometimes?  A lot of moisture in atmosphere will cause all particles to scatter, or if there is no cloud cover and if the sun is overhead, the sun will look whitish because all visible light passes to your eye.  But don’t look directly at the sun!

Absorption  Any solar energy that is NOT reflected is absorbed.

All Energy Reaching Earth  Energy that reaches Earth is either reflected or absorbed  How much is reflected or absorbed depends on surface  The fraction that is reflected is called albedo

Albedo  This determines the level of reflectivity of a substance.  The higher the Albedo number, the more reflective a substance is.  Examples: Snow albedo = 95 (95% reflected, 5% absorbed) Snow albedo = 95 (95% reflected, 5% absorbed) Forest albedo = 10 (10% reflected, 90% aborbed) Forest albedo = 10 (10% reflected, 90% aborbed) Grass albedo = 26 (26% reflected, 74% aborbed) Grass albedo = 26 (26% reflected, 74% aborbed)

Other Reasons Temp Varies Throughout the Planet  Latitude (hottest on the equator due to more direct sunlight)

Other Reasons Temp Varies Throughout the Planet  Altitude (Colder at higher elevations due to less moisture and air molecules to absorb heat)

Other Reasons Temp Varies Throughout the Planet  Bodies of Water (Water abosorbs heat well and therefore areas around water have more moderate temperature ranges)

Greenhouse Effect  Trapping of infrared heat by gas molecules reflecting infared heat in the atmosphere back to earth.  These infared rays are reflected back to earth where the warm earth’s surface again.

Why is some energy reflected back?  Let’s draw a diagram

3 Views on Global Warming due to increase in greenhouse effect.  Nat Geo Nat Geo Nat Geo  Glen Beck Glen Beck Glen Beck  Past President of the United States Past President of the United States Past President of the United States

3 Ways Heat Moves

Conduction: Heat transfer by direct contact

Convection: heat transfer by air current

In your notes make a prediction.  What will happen if you hold a balloon of Air and a balloon of water over a flame?  WHY!

Let’s Try a Demonstration!  Why does one balloon pop in the flame and the other does not? Explain in scientific terms!

But WHY are all the wind patterns curved and not straight?  Coriolis Effect…

Let’s see what you know?  Turn to a blank page in your notes…

Where could this sunset be and why is it not red?

Label Conduction, Radiation, Convection

What types of energy is blocked by the ozone layer?

 What is the greenhouse effect (diagram/label it)? Explain yourself please…  What is global warming? How is it different from the greenhouse effect?

How does Conduction Work? Be very specific and diagram/label it!

How does Convection work? Be very specific, diagram/label it!

What is air pressure? How do we change it in a closed system?

Wind questions…  Where does wind come from?  Why is there a low pressure system on (close to) the equator?  Why don’t the winds just blow north to south in the N. Hemisphere and south to north in the S. Hemisphere?

Answer this…  Explain why if you were in a ship 5 miles north of me and I aimed a cannon directly at your boat and I shot a cannon ball at you, it would be unlikely I would hit you without altering my cannon direction?