New Unit! Weather Variables Question of the Day What’s the structure of the atmosphere? New Unit! Weather Variables Can you name Earth’s 3 spheres, in order from highest to lowest? Atmosphere, Hydrosphere, Lithosphere 100

1. Atmosphere 2. Hydrosphere 3. Lithosphere A. Water B. Gas C. Rock Match up the Spheres of the Earth 1. Atmosphere 2. Hydrosphere 3. Lithosphere A. Water B. Gas C. Rock

Atmosphere Gas Hydrosphere Water Lithosphere Rock Are these spheres in order of increasing or decreasing density? Atmosphere Gas Hydrosphere Water Lithosphere Rock

Lowest to highest density

Layers of Atmosphere Based on temperature differences

4 Layers of Atmosphere

Interfaces Between Layers Pauses (Stops) - Interfaces Between Layers Named after layer below EX. Tropopause Top of Troposphere

1. Troposphere Lowest layer Weather Decreasing temp. with altitude

2. Stratosphere - Earth’s Sunscreen Ozone Layer O3 absorbs UV Increasing temp. with altitude Airplanes fly here

3. Mesosphere Very little ozone Decreasing temp. with altitude Coldest layer Meteors burn up

4. Thermosphere “Thermo” = heat Dramatically increasing temp. with altitude HOT!!! >1000º C Intense insolation

Does Air Have Mass? Does Air Have Volume?

Mass Volume Density = Amount of matter in an object Amount of space an object occupies Mass Volume Density =

Which layer has the greatest density Which layer has the greatest density? (Hint: think about the order of layers) Thermosphere Mesosphere Stratosphere Troposphere

1. As altitude increases in the stratosphere, air temp. _________ 2. Ozone is concentrated at altitudes 20 - 35 km. Which layer has the greatest concentration of ozone? 3. What do tropopause, stratopause and mesopause all have in common? 4. What’s the altitude of mesopause? 5. Earth’s atmosphere is divided into 4 layers based on ____________ ?

Layers of Atmosphere - Answers 1. Temperature increases 2. Stratosphere 3. Each is an interface between two layers of the atmosphere 4. 80 km. (or 50 mi.) 5. Earth’s atmosphere is divided into 4 layers based on temperature

Question of the Day What is the composition of the atmosphere? 1) Please take out ESRT 2) Draw this graph in notebook 3) Fill in graph for the Troposphere Altitude Temperature 101

Alt. Temp.

Atmospheric Pressure Also called Barometric Pressure or Air Pressure Due to weight of overlying atmosphere pushing down

Which layer has the most air pressure?

Water Vapor Mostly in Troposphere Decreases with altitude

Composition of Troposphere? 78% N, 21% O, 1% Other (gases and dust)

Elements and compounds constantly moving between spheres - recycling Atmospheric Balance Elements and compounds constantly moving between spheres - recycling H2O O2 CO2

Question of the Day How is the atmosphere heated? Please take out Composition worksheet and ESRT In which layer of the atmosphere does most weather occur? 1) Tropopause 2) Stratopause 3) Troposphere 4) Stratosphere 102

Question of the Day How is the atmosphere heated? In which layer of the atmosphere does most weather occur? 1) Tropopause 2) Stratopause 3) Troposphere 4) Stratosphere 102

Weather Weather Variables Condition of the variables of the atmosphere Weather Variables Temperature, air pressure, wind, moisture, cloud cover, precipitation, storms

Heating of Atmosphere Direct absorption of insolation Conduction - air touches Earth Absorption of infrared radiation from Earth by Greenhouse Gases

Condensation (water vapor → liquid) Sublimation (water vapor → ice) Ex.: clouds, fog, dew, frost

Coriolis Effect - friction at interface of atmosphere & Earth

Expansion and Compression of Air Gas expands, temperature ↓ Gas is compressed (contracted), temperature ↑

Transfer of Heat Energy Convection Currents Differences in air density → differences in air pressure Winds are the part of convection currents parallel to Earth

Regents Question The transfer of heat energy within the troposphere occurs primarily by: 1) insolation 2) conduction 3) radiation 4) convection

Regents Question As a mass of air rises in the troposphere, its temperature will: 1) decrease due to expansion 2) decrease due to compression 3) increase due to expansion 4) increase due to compression

Activity What would you experience if you could ride an open elevator through the atmos- phere? Write a travelers’ guide to an elevator ride to a point 150 km above Earth. Describe changes in 1) temperature, 2) air pressure, 3) water vapor. Also, describe protective equipment you’d need to survive the trip. Bon voyage!

Question of the Day What factors affect air pressure? When gas expands, temperature ____. HINT: When gas is compressed, temperature _____. HINT: 103

Atmospheric Pressure = Barometric Pressure = Air Pressure Pressure due to weight of overlying atmosphere pushing down

Barometer Measures air pressure in millibars (mb) or inches 1. Mercury Barometer Air pushes down on mercury Mercury rises in closed tube

2. Aneroid Barometer Metal can that’s a partial vacuum expands & contracts with changes in air pressure

Pressure Chart What’s the interval? mb scale ____ in. scale ____ Standard air pressure (1 atmosphere or atm.) at sea level is 1013.2 mb = 29.92 in. of Hg What’s the interval? mb scale ____ in. scale ____

Convert these readings: 1022.8 mb = 30.20 in. 30.53 in. = 1034.0 mb 29.81 in. = 1009.5 mb

Isobar Isoline connecting points of equal barometric pressure

Temperature vs. Air Pressure Temperature increases ↑ Air expands Density & pressure decrease ↓

Water Vapor vs. Air Pressure Greater amount of H20 (humidity) ↑ Lower the density and pressure ↓ H20 weighs less than < N2 or 02

Altitude vs. Air Pressure High altitude Low density ↓ Low pressure ↓ Low altitude High density ↑ High pressure ↑

Summary Temperature ↑ Water Vapor ↑ Altitude ↑ Decreases Decreases Density Pressure Temperature ↑ Water Vapor ↑ Altitude ↑ Decreases Decreases Decreases Decreases Decreases Decreases