Chapter 23 - The Atmosphere

Chapter 23:

Chapter 23 The Atmosphere

Section 23.1 - Characteristics of the Atmosphere :

Section 23.1 - Characteristics of the Atmosphere Objectives: SSBAT 1. Discuss the composition of the earth’s atmosphere. (pp. 455–457); Do Now ( ¼ ): What percentage of the atmospheric gases do you believe to be oxygen? How can you test for oxygen? (Hint: Where is oxygen needed?)

Test for 21% Oxygen:

Test for 21% Oxygen Percentage of Oxygen Lab Demo Data in Class Questions for HW

Section 23.1 Objectives (Day 2):

Section 23.1 Objectives (Day 2) SSBAT evaluate the two major atmospheric gases and their cycles Do Now: What are the two major gases in the atmosphere?; One gas has a second form, which is it?

Composition of the Atmosphere Figure 23-1 p. 455:

Composition of the Atmosphere Figure 23-1 p. 455 78% 21% 0.9% 0.1% Nitrogen N 2 (78%) Oxygen O 2 (21%) Other Gases (~1%) Argon Ar = 0.93% Carbon Dioxide CO 2 = 0.03% Water Vapor H 2 O (g)= 0.0 to 4.0% Neon, Helium, Methane, Krypton, Xenon, Hydrogen, Ozone = Trace Transparency Wkst 35 Composition of the Atmosphere

The Major Gas Cycles:

The Major Gas Cycles The Oxygen Cycle The Nitrogen Cycle

The Oxygen Cycle (1:17):

The Oxygen Cycle (1:17)

Oxygen in the Atmosphere Figure 23-2 p. 456:

Oxygen in the Atmosphere Figure 23-2 p. 456

The Nitrogen Cycle (2:28):

The Nitrogen Cycle (2:28)

Nitrogen in the Atmosphere Figure 23-3 p. 457:

Nitrogen in the Atmosphere Figure 23-3 p. 457

Day 2 Classwork/Homework:

Day 2 Classwork/Homework Transparency Wksts The Oxygen Cycle The Nitrogen Cycle

23.1 Day 3:

23.1 Day 3 Objectives SSBAT describe the layers of the atmosphere SSBAT explain how two types of barometers work Do Now What is the main protective layer of the atmosphere that protects us from ultraviolet (UV) rays; where is it found? (Hint: One of the types of oxygen) Define gas (air) pressure.

Atmospheric Pressure:

Atmospheric Pressure Unit of measurement = Pascal (Pa) 1 Pa = 1 N/m 2 Calculated : In one square meter, a column of air has a mass 10,300 kg. This mass puts a force (weight) of 101,325 N on the surface. This is the force of 1 atmosphere or 1 atm. 1 atm = 101,325 N/1m 2 =101,325 Pa or 101.3 kPa

Barometer:

Barometer An instrument that measures atmospheric pressure Mercurial barometer – atmospheric pressure pushes mercury up a tube. The height of the mercury measures the atm. Pressure. 1 atm = 760mm Hg Aneroid Barometer – measures “without mercury.”

What is the Atmosphere? (1:14):

What is the Atmosphere? (1:14)

Greatest Discoveries: Troposphere and Stratosphere (3:10):

Greatest Discoveries: Troposphere and Stratosphere (3:10)

Layers of the Atmosphere:

Layers of the Atmosphere Differentiated by temperature changes, not pressure changes. Troposphere – closest to the earth’s surface. All weather changes occur here. tropopause – top of the layer Stratosphere – extends upward from the tropopause to an altitude of 50 km. stratopause – upward boundary of layer Mesosphere – Next 80 km; top = mesopause Thermosphere – top of atmosphere Lower – ionosphere Upper - exosphere

Temperature Change in the Atmosphere Figure 23-5 p. 460:

Temperature Change in the Atmosphere Figure 23-5 p. 460

Temperature Change in the Atmosphere (from the ground up):

Temperature Change in the Atmosphere (from the ground up) Troposphere – Temperature decreases with altitude Stratosphere – ozone in this layer allows the temperature of the air to increase Mesosphere – temperature drop Thermosphere – nitrogen and oxygen atoms can absorb solar energy

Section 23.1 - Characteristics of the Atmosphere :

Section 23.1 - Characteristics of the Atmosphere Objectives: SSBAT 4. Identify the weather conditions that increase the effects of air pollution. (p. 462) Do Now ( Full Sheet ): Using at least 3 of the following words, write a couple of sentences explaining the importance of the Atmosphere. Troposphere Stratosphere Ozone Mesosphere Thermosphere Ionosphere Exosphere Nitrogen Cycle Oxygen Cycle Mercurial Barometer Aneroid Barometer Air Pressure

Ozone Facts:

Ozone Facts Three (3) molecules of oxygen per molecule of ozone – O 3 Found in the Stratosphere Protects the earth’s inhabitants by absorbing harmful UV rays from the sun CFCs (Chlorofluorocarbons) using in refrigerators and air conditioners, etc break down ozone.

Ozone Hole Progression:

Ozone Hole Progression Image above: View of the South Pole from NASA's TOMS (Total Ozone Mapping Spectrometer) satellite. Blue and green indicate relatively large amounts of ozone. Red and yellow mark the "ozone hole," an area of decreased ozone. Credit: NASA Source: CSIRO Atmospheric Research; Data NASA GSFC Code 916

Ozone Hole Area Graphed:

Ozone Hole Area Graphed Source: CSIRO Atmospheric Research; Data NASA GSFC Code 916

Air Pollution:

Air Pollution Air pollutant – substance in the atm. harmful to people, animals, plants, or property Acid precipitation Temperature inversion (p.462) – pollution trapped by layer of warm air in-between layers of cool air (See Next Slide) Smog – smoke and fog

Temperature Inversion and Pollution:

Temperature Inversion and Pollution

Weather Smart: Ozone and Pollution :

Weather Smart: Ozone and Pollution

Classwork/Homework:

Classwork/Homework 23.1 WKST

Section 23.2 Objectives:

Section 23.2 Objectives Objectives : SSBAT summarize the processes of radiation, conduction, and convection. Do Now Pick up Venn Diagram (Hold at desk) (¼) How is heat transferred? ( Hint: There are three (3)?)

Notes for Conduction :

Click Here for an interactive animation of heat transfer Notes for Conduction 

Notes for Convection :

Click Here for an interactive animation of heat transfer Notes for Convection 

Notes for Radiation :

Click Here for an interactive animation of heat transfer Notes for Radiation 

Slide 32:

Transfer Of Energy ? ? ? ? Needs matter to transfer energy No physical movement of matter ? ? ? ? Energy is moving Transfer of heat through the movement of fluids ? Transfer of heat through the direct contact of matter Transfer of heat through electromagnetic waves

Radiation:

Radiation Definition : Heat transferred through waves Atmosphere absorbs some of the radiation before reaches earth’s surface. Travels at very high speeds 300,000 km/s or 3 x 10 8 m/s 671,080,887 mph .016 s to travel from east coast to west coast Wavelength ( λ ) – distance from one wave crest to the next

Electromagnetic Spectrum:

Electromagnetic Spectrum

Electromagnetic Spectrum:

Electromagnetic Spectrum Visible light = 400 nm – 700 nm Shorter λ = UV, X-rays, and gamma rays Longer λ = infrared, microwaves, and radio

Section 23.2 Objectives:

Section 23.2 Objectives Objectives : SSBAT explain how radiant energy reaches the earth; describe how visible light and infrared energy warm the earth. Do Now (In PPT Packet) Why is the sky blue?

Scattering:

Scattering THE REASON THE SKY APPEARS BLUE Clouds, dust, and gas molecules in the atmosphere cause scattering of light. Short λ are more easily scattered; (Blue light has a short wavelength) Long λ aren’t easily scattered; Gives the sun its Reddish-Orange color

Transmitted Solar Energy:

Solar Energy (100%) = Scattered Reflected (30%) + Absorbed (20%) + Transmitted (50%) Of the amount of energy that reaches the surface, only 50% of that energy is absorbed 25% of the Solar energy that reaches earth is absorbed by the earth’s surface (50% of 50%) Transmitted Solar Energy

Albedo:

Albedo Percent of solar radiation reflected by a surface i.e. Earth = .3 Moon = .7 Reflection and Absorption (Table 23-1 p. 465) Percentage of solar radiation Surface Reflected Absorbed Soils (Dark colored) 5-10 95-90 Desert 20-45 80-55 Grass 16-26 84-74 Forest 5-20 95-80 Snow 40-95 60-05 Water (high sun angle) 3-10 97-90 Water (low sun angle) 10-80 90-20

Section Review 23.2:

Section Review 23.2

Section 23.3 Objectives :

Section 23.3 Objectives SSBAT describe the global patterns of wind SSBAT describe some factors that create local wind patterns Do Now: Why does the wind blow?

Winds if the Earth did not rotate:

Winds if the Earth did not rotate

Earth’s Rotation and Weather (2:18):

Earth’s Rotation and Weather (2:18)

Coriolis Effect:

Coriolis Effect

Coriolis Effect:

Coriolis Effect Trade winds – winds in both hemispheres flowing toward the equator between 30 o and 0 o Doldrums – narrow zone where trade winds meet Horse latitudes – belt of high pressure in the vicinity of 30 o latitude created by descending air Westerlies – wind belts in both hemispheres between 60 o and 30 o (N-Hemisphere = SW winds; S-Hemisphere = NW winds) Polar easterlies – above 60 o

Other Atmospheric movements:

Other Atmospheric movements Jet streams – Upper westerly high speed winds in the upper troposphere and lower stratosphere over both Northern and southern hemispheres.

Local Winds:

Local Winds Sea Breeze – wind moving from water to land (generally begins in afternoon) Land Breeze – wind from cooler land to the warmer water.