Goal 2 - Sewell's Science Sitemsewell.weebly.com/uploads/7/0/4/5/70453749/goal_2_5_lessons_1-3... · Radiation –transfer of energy ... b/c condensation is the process of water vapor

Goal 2.5 The Atmosphere

Lesson 1 Atmospheric Basics

Think About It…

Why would it be a bad thing if the atmosphere was

mostly oxygen?

Focus Question…

What is the structure and function of the atmosphere?

Atmospheric Composition…

• Nitrogen – 78%

• Oxygen – 21%

• Argon - .93%

• Carbon Dioxide - .03%

• Water Vapor - .0 to 4%

• Trace Gases

http://www.bbc.co.uk/schools/gcsebitesize/science/21c/atmosphere/chemicalsairrev1.shtml

Key Atmospheric Components

• Oxygen

–Gas

–Living things need oxygen to break down food for energy

http://schoolworkhelper.net/wp-content/uploads/2010/07/oxygen-transport.jpg


• Carbon Dioxide

–Gas

–Minor role in absorbing heat

–plant fertilizer

http://ed101.bu.edu/StudentDoc/current/ED101fa10/ccburke/Photosynthesis.html


• Ozone

–Gas

–Absorbs ultraviolet radiation from the sun

http://mmedia.pl/ozone-layer-diagram-for-kids


• Water Vapor

–Gas

–Major role in absorbing heat

–source of clouds, rain, and snow


• Water

–Liquid

–The source of rain

Singing in the Rain!

http://mypeartreehouse.blogspot.com/


•Ice

–Solid

–Makes up snow, sleet, and hail

Legendary Vail Powder! http://www.austinskiers.org/trips0910/vail0910.htm


• Dust and Salt –Solids

–Provide a solid surface for water vapor to condense around (so that clouds can form)

–See next slide…

Salt Spray from Waves

http://www.kidsgeo.com/images/ocean-waves.jpg

Dust Storm http://www.weatherfreaks.net/images/dust_storm3.jpg

Condensation Nuclei…

http://www.sci.uidaho.edu/scripter/geog100/lect/05-atmos-water-wx/ch5-part-5-clouds-fog.htm

•http://ds9.ssl.berkeley.edu/lws_gems/3/images_3/layat510.jpg

The Structure of the Atmosphere …

The Structure of the Atmosphere – The Troposphere

• Description…

–0-11 km

–highest air pressure

–Contains most of the gases of the atmosphere

• Objects Found There

–Weather

– life forms

– jets

The Structure of the Atmosphere – The Stratosphere

• Description…

–11-48 km

–Molecular heat rises due to the ozone absorbing heat


–Ozone layer

–Weather balloons

The Structure of the Atmosphere – The Mesosphere

• Description…

–48-95 km

–Molecular heat falls b/c there’s not a whole lot here!


–Meteors (shooting stars) burn here

The Structure of the Atmosphere – The Thermosphere

• Description…

–95-550 km

–Molecular heat rises


– Ionosphere

–Auroras

The Auroras… http://www.lovethesepics.com/2011/02/24-amazing-auroras-aurora-borealis-

aurora-australis/

http://www.lovethesepics.com/2011/02/24-amazing-auroras-aurora-borealis-aurora-australis/













The Structure of the Atmosphere – The Exosphere

• Description…

–Above 600 km

–Outermost layer

–Space!


–Some H and He

–Satellites

Temperature Variations with Altitude

http://www.aerospaceweb.org/question/atmosphere/atmosphere/layers.gif

The layers are divided by temperature!

What Happens to the Sun’s Energy?

http://www.physicalgeography.net/fundamentals/images/cascade.GIF

Solar Fundamentals…

a. Radiation

– transfer of energy through space by visible light, ultraviolet radiation, and other electromagnetic waves

–Earth’s surface is warmed by the sun’s rays

http://ossfoundation.us/projects/environment/global-warming/earths-radiation-budget


a. Conduction

– transfer of energy when molecules collide

–Air molecules above Earth’s surface are warmed when they contact the warm surface of Earth


a. Convection

–transfer of energy by flow of a heated substance

–Warm air rises, then cools and sinks http://avstop.com/ac/fig5-9.jpg

The Transfer of Heat in the Atmosphere…

Copy the diagram your teacher draws on the

board!

Lesson 2 The State of the

Atmosphere

Think About It…

What makes a hot air balloon float?

Focus Question…

What are the physical properties of the

atmosphere that create weather?

Temperature of the Atmosphere…

1. What is temperature?

…measurement - how rapidly or slowly molecules move

2. What is heat?

…transfer of energy that occurs because of a difference in temperature between substances

a. Heat fuels atmospheric processes!

The Temperature of the Atmosphere

b. The thermosphere is the hottest layer of the atmosphere but it feels so cold…

b/c even though molecules are moving very fast (which means they are very hot), they are so far apart that there would be no heat transfer.

Astronaut Bruce McCandless II is feeling no heat!

http://www.newworldencyclopedia.org/entry/Astronaut

http://static.newworldencyclopedia.org/8/88/Astronaut-EVA.jpg


Write scales in margin…

o Fahrenheit… o Boiling point

… 212 o Freezing point

… 32 o Absolute Zero

… -523


o Celsius…

o Boiling point … 100

o Freezing point … 0

o Absolute Zero …

-273


o Kelvin… o Boiling point …

373

o Freezing point … 273

o Absolute Zero … 0

o There are NO negative numbers on the Kelvin scale!

Absolute Zero… Absolute zero is the temperature at which molecular

motion theoretically stops! This does not occur anyplace in the universe.

http://www.happynews.com/news/562009/happens-absolute-zero.htm







3. Dew Point - temperature to which air must be cooled (at constant pressure) to reach saturation.

o That is when dew is formed!

o The higher the dew point, more humid and uncomfortable the air.

o See next slide…

Dew Point…

http://www.goerie.thinkhost.com/mt/st_weather/DEW_POINT_CHART_full.JPG

The Temperature of the Atmosphere 3a. Water vapor in the atmosphere becomes water droplets

3b. Dew point is also called condensation temperature b/c condensation is the process of water vapor

changing into liquid water.

(Remember the condensation nuclei?)

Vertical Temperature Changes

4. Altitude … height above ground or sea level.

a. Why is the temperature of the lower atmosphere cooler at higher elevations and altitudes?

… b/c it is farther away from the source of heat – conduction from Earth’s surface

… Individual air masses moving upward through the atmosphere… will cool about 10 degrees C/1000 m.

Vertical Temperature Changes 4b. What is lifted condensation level?

… height at which condensation occurs

… The LCL often corresponds to the base of the clouds!

Air Pressure and Density… 1. Density is mass per volume. As altitude increases (moving up through

Earth’s atmosphere), the density of the air...

… decreases

2. Air pressure is… … force exerted by molecules of

atmosphere as they are pulled toward Earth’s center.

a. As altitude increases… air pressure decreases

Air Pressure and Density…

2b. Air at the bottom of the atmosphere has higher density and pressure because...

… of the greater mass of the atmosphere above you (it contains the most gases)

… Gravity is the force pulling all air molecules in the atmosphere toward Earth.

… This is similar to being at the bottom of the ocean with tons of water above you!

… We are accustomed to the high air pressure so it doesn’t squash us.

Temperature-Density Relationship

1. The Relationship between Temperature and Density: Warm Air…

a. As temperature increases… density decreases.

b. Warm air is less dense and will rise.

c. The upward movement of warm air lowers pressure.

d. So, warm air rising causes low pressure.

Temperature-Density Relationship

2. The Relationship between Temperature and Density: Cold Air…

a. As temperature decreases… density increases.

b. Cold air is more dense and will sink.

c. The downward movement of cold air raises pressure.

d. So, cold air sinking causes high pressure.

Temperature Inversion

3. Definition…when upper layers of troposphere are warmer than lower layers.

– Warmer layers are above colder layers.

– Cause … on cold, clear, winter night, surface cools rapidly & becomes colder than air above it, resulting in upper layer being warmer!

– The warm layer can trap pollution or melt snow.

–http://www.wrh.noaa.gov/slc/climate/TemperatureInversions.php

d. Draw this…

http://www.wrh.noaa.gov/slc/climate/TemperatureInversions.php

1. Creating Wind… a. Cool air, which is

denser, sinks.

b. This forces the warm air, which is less dense to move upwards.

c. Air moves from areas of high density to areas of low density.

d. In its simplest form, wind can be thought of as air moving from an area of high pressure to an area of low pressure.

http://scifiles.larc.nasa.gov/text/kids/Problem_Board/problems/light/sim3.html

Wind…

2. The density imbalances that move air to produce wind are created by…

The unequal heating and cooling of Earth’s surface

3. Wind is measured by… anemometers (mph or kph)

4. Wind speeds increase at high altitudes b/c…

There are few to no obstacles there

Humidity Changes with Temperature…

1. What is humidity?

o The amount of water air can hold at a given temperature. This is a constant!

2. What is relative humidity?

o The amount of water the air is actually holding compared to how much it can hold

Humidity Changes with Temperature…

3. How much water vapor can a m3 of air hold at 25 degrees C?

o 24 grams

4. How much water vapor can a m3 of air hold at 15 degrees C?

o 13 grams

5. Why does the air hold more water at 25 degrees than it does at 15 degrees C?

o Warm air can hold more water than cold air because it is less dense.

6. How much water (per m3) would the air hold in a room at 25 degrees C if the relative humidity was 50%?

o 12 grams

Lesson 3 Moisture in the

Atmosphere

Think About It…

Can you forecast the weather by looking at

clouds?

Focus Question…

How are clouds formed and what does each type indicate about the

weather?

Three Ways Clouds Can Form…

a. from convection currents

b. from warm air rising over mountains (orographic lifting)

c. when air masses of different temperatures meet

Cloud Formation – Convection Currents

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/cld/cldtyp/home.rxml

Cloud Formation – Orographic Lifting

http://www.envi.hufs.ac.kr/gwlee/session6/lift.html

Clouds form over a mountain.

Cloud Formation – Frontal

http://www.windows2universe.org/earth/Atmosphere/images/cloudformation_Fronts_small.jpg

Cloud Types…Altitude

• Cirro- high

–Above 6000m

• Alto - middle

–Between 2000-6000m

• Stratus - low

–Below 2000m

http://www.windows2universe.org/earth/Atmosphere/clouds/cloud_heights.html

http://www.windows2universe.org/earth/Atmosphere/clouds/images/cloud_height_graphic2_large_jpg_image.html

Cloud Types… Meaning

•Cirrus –Latin for “hair”

–Wispy, stringy clouds

http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/cirrus.rxml?hret=/guides/mtr/cld/cldtyp/home.rxml

Cloud Types

•Cumulus –Latin for “pile” or “heap”

–Puffy, lumpy clouds


Altocumulus

Cloud Types

•Stratus –Latin for “layer”

–Featureless sheets of clouds


Cirrostratus “Halo” around sun

Nimbostratus

Cloud Types

•Nimbus –Latin for “cloud”

–Low, gray rain clouds


Nimbostratus

Cloud Types

• Cumulonimbus

–Latin for “puffy cloud”

–Enormous rain clouds

http://ed101.bu.edu/StudentDoc/current/ED101sp10/erikalee/cumulonimbus%20clouds.html

The Water Cycle… A Review!

a. Water on Earth’s surface will turn to water vapor in the process of…

o evaporation.

b. Water vapor in clouds turns to liquid by

o condensation.

c. Rain, snow, sleet, or hail falls to Earth’s surface as

o precipitation.

http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/hydrosphere/hydrologic_cycle.html

Clouds…

http://eo.ucar.edu/webweather/images/cloudchart.gif

More Clouds!

http://apollo.lsc.vsc.edu/classes/met130/notes/chapter5/summary.html

Lesson 3 Cloud Model… • p. 288

• Create 10 clouds.

• Get a piece of blue paper.

• Title it “Clouds” and write your name(s) on the bottom left.

• Draw the ground.

• Mark the altitude on left side.

• Draw a sun.

• Glue the clouds on and label them.

• Draw rain drops under the 2 nimbus clouds.

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Goal 2 - Sewell's Science Sitemsewell.weebly.com/uploads/7/0/4/5/70453749/goal_2_5_lessons_1-3... · Radiation –transfer of energy ... b/c condensation is the process of water vapor