Meteorology

What is the Atmosphere? Mixture of gases that surround the Earth. Composition 78% Nitrogen 21% Oxygen 1%: other argon, carbon dioxide What is the purpose of the atmosphere? Makes conditions suitable for us to live Protects us from space

What is the Atmosphere: continued Why is it Important? Stores Oxygen Keeps us warm: Greenhouse effect Protects us from sun’s radiation, cold of space, meteoroids

Air Pressure Does air have mass? How could you prove/demonstrate that air has mass? Measure of force with which air molecules push on a surface Air pushes in all directions Gases will fill the volume of space they are contained Density of air effects the amount of pressure, why? How is pressure measured?

Altitude and Air pressure Altitude = Elevation Air pressure decreases as altitude increases Air pressure decreases, density decreases

Layers of Atmosphere 4 main layers Troposphere Stratosphere Mesosphere Thermosphere

Troposphere Tropo = Change Layer in which we live Weather occurs here What is the difference between weather and climate? Majority of mass of atmosphere Altitude increases, temperature decreases Top temp. = -60 degrees Celsius 0 to 12 km

Stratosphere Contains the Ozone What is ozone? 3 oxygen molecules bonded together Top of Stratosphere is warm, but bottom is cold, Why? Ozone absorbs Suns radiation Ranges from 12km to 50 in elevation

Mesosphere Layer protects us from meteoroids and space junk Meteoroids burn up = Shooting stars

Thermosphere Divided into 2 layers Outermost layer of atmosphere Exosphere Ionosphere Outermost layer of atmosphere Temp can reach up to 1,800°C Suns radiation strikes this layer first Thermometer would read 0°C, Why? Density and distance between molecules. Molecules have a lot of energy but there isn’t a lot of molecules and they are spread out Temperature = Average amount of energy of motion of each particle

Thermosphere: Ionosphere Sun’s energy innervates gas molecules to become electrically charged Ions We see this as Auroa Borealis: Northern Lights Layers reflects back radio waves

Thermosphere: Exosphere 400 km and beyond Layer in which satellites orbit Earth