Chapter 14 The Atmosphere 1 The Atmosphere Evolves

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Chapter 14: The Atmosphere 1. The Atmosphere Evolves 2. Structure and Processes of the

Chapter 14: The Atmosphere 1. The Atmosphere Evolves 2. Structure and Processes of the Atmosphere 3. Solar Radiation and the Atmosphere 4. The Role of Water in the Atmosphere 5. Air Pressure, Condensation, and Precipitation 6. Clouds and Frontal Systems 7. Winds Copyright © The Mc. Graw-Hill Companies, Inc. Permission required for reproduction or display.

Learning Objectives • • • Students will explain concepts related to the atmosphere. Students

Learning Objectives • • • Students will explain concepts related to the atmosphere. Students will describe the makeup of the atmosphere and its layers. Students will explain the connections between solar radiation and the atmosphere. Students will identify how humidity measurements will differ as atmospheric conditions change. Students will relate air pressure to air temperature and air density. Students will explain what happens to rising air and analyze how adiabatic temperature changes occur. Students will describe the process of cloud formation and recognize some basic cloud types. Students will describe the causes of winds, cyclones, and anticyclones. Students will interpret a weather map to determine wind directions and relative wind speeds.

The Atmosphere Evolves Wrigley Field, Chicago, IL Why is it easier to hit home

The Atmosphere Evolves Wrigley Field, Chicago, IL Why is it easier to hit home runs at Coors Field? Coors Field, Denver, CO The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Evolves • Kittinger’s descent − August 16, 1960, Captain Joe Kittinger (USAF)

The Atmosphere Evolves • Kittinger’s descent − August 16, 1960, Captain Joe Kittinger (USAF) jumps from a balloon capsule 20 miles in the air − Highest sky dive in history (airplanes fly at ~6. 8 miles altitude) − Researching whether astronauts could bail from troubled spacecraft still in the atmosphere − During his ascent, his balloon expanded, and the sky turned black − He was protected by a pressurized suit and an oxygen supply − Could see the curvature of the Earth on the horizon − He reached speeds of 614 mph on descent − Rushed towards Earth for about 4 minutes, gradually slowing as he approached its surface (before he deployed his parachute) The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Evolves • Our atmosphere = the air (specific mix of gases) around

The Atmosphere Evolves • Our atmosphere = the air (specific mix of gases) around us • Protects Earth from harmful solar radiation, and incoming projectiles. • Lower bound – touches surface of Earth • Upper bound – gradual transition into space • Observed from space the atmosphere is a thin shell around Earth The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Evolves • What is the atmosphere made of? − Mostly Nitrogen and

The Atmosphere Evolves • What is the atmosphere made of? − Mostly Nitrogen and Oxygen − CO 2 is a small component but plays a large role in the greenhouse effect − Water vapor in the air can range from 0% over deserts to 7% in humid climates Is the atmosphere of the Earth stable or is it changing with time? Why? The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Evolves • Having an atmosphere is not unique to Earth, but our

The Atmosphere Evolves • Having an atmosphere is not unique to Earth, but our atmosphere’s composition is unique. − Venus and Earth began with very similar atmospheres rich in carbon dioxide, hydrogen, and oxygen. − The atmospheres originated from gases expelled from extensive volcanism and collision with comets/meteorites. − Venus being closer to sun had abundant water vapor. This vapor was split into hydrogen and oxygen, and hydrogen was lost to space. Remaining oxygen bonded with carbon abundant CO 2. − CO 2 blanket around Venus insulates planet 867°F on the surface! The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Evolves Earth No oxygen present 4 billion years ago. -As Earth cooled,

The Atmosphere Evolves Earth No oxygen present 4 billion years ago. -As Earth cooled, water condensed, rained, removed CO 2 from the atmosphere. -Early primitive organisms used photosynthesis to consume CO 2 and produce oxygen -Oxygen accumulated in oceans but not atmosphere until about 2 billion years ago (oxygen is reactive and combined with other elements in early rocks) Key Point: Life Came Before Free Oxygen in Earth’s Atmosphere Earliest animals lived in oceans. Oceans protected them from harmful solar radiation. Once oxygen accumulated in Earth’s atmosphere, life could be sustained on land. This is also when the ozone layer developed, protecting life on land from UV rays. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Self Reflection Survey Answer the following questions as a means of uncovering

The Atmosphere Self Reflection Survey Answer the following questions as a means of uncovering what you already know about oceans and coastlines: 1. List the ways in which human beings interact with the atmosphere. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Self Reflection Survey Answer the following questions as a means of uncovering

The Atmosphere Self Reflection Survey Answer the following questions as a means of uncovering what you already know about oceans and coastlines: 2. Describe the variations you have observed in the atmosphere where you live or from your travels to other locations. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Self Reflection Survey Answer the following questions as a means of uncovering

The Atmosphere Self Reflection Survey Answer the following questions as a means of uncovering what you already know about oceans and coastlines: 3. What characteristics of the atmosphere are typically described in weather forecasts? The Good Earth/Chapter 14: The Atmosphere

Go back to the Table of Contents Go to the next section: Structure and

Go back to the Table of Contents Go to the next section: Structure and Processes of the Atmosphere The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere − Gravity holds 99% of atmospheric gases within

Structure and Processes of the Atmosphere − Gravity holds 99% of atmospheric gases within 20 miles of the Earth’s surface • The density of air rapidly decreases with increasing altitude. • The accepted boundary with space is 62 miles above Earth’s surface. • Few gas molecules exist here. • Some gas must extend as high as 312 miles high, as spacecraft can feel drag up to this altitude. • Atoms in water or air are constantly in motion = kinetic energy. Kinetic energy increases as speed of atomic motion increases Heat = the total kinetic energy of all the atoms in a substance Temperature = the average kinetic energy of a substance measured for a given quantity of the substance The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere The above pans of water are heated to

Structure and Processes of the Atmosphere The above pans of water are heated to the same temperature for the same amount of time. They contain the same amount of heat, which is spread among the water molecules in each pan. But the water in pan 2 has a higher temperature, as the heat would have produced more rapid motion among fewer water molecules. The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere Recall – Water has a high heat capacity!

Structure and Processes of the Atmosphere Recall – Water has a high heat capacity! In other words, it must absorb a lot of heat to produce a corresponding temperature increase The heat capacity of air is ¼ than that of water. If the same amount of heat were applied to similar masses of air and water, which would experience a greater temperature increase? Air would experience a greater temperature increase, as it doesn’t take as much heat to raise the temperature of a given mass of air vs. water. The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere 4 thermal layers of the atmosphere Troposphere: Shows

Structure and Processes of the Atmosphere 4 thermal layers of the atmosphere Troposphere: Shows a decrease in temperature with altitude. Gets its warmth from the Earth’s surface. Contains our weather systems. Air pollution collects here. The bulk of air and aerosols reside here. Thickness varies based on its thermal character. Thickest (10 miles) over equator and thinnest (5 miles) over poles. The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere Stratosphere: Shows an increase in temperature with altitude.

Structure and Processes of the Atmosphere Stratosphere: Shows an increase in temperature with altitude. Over 25 miles thick. Contains ~20% of the atmosphere’s air. This is where ozone resides, which blocks out harmful ultraviolet solar radiation. Temperature increase is due to absorption of solar radiation by ozone molecules. Higher kinetic energy (nothing to bump into). The cool air of the troposphere cannot rise into the stratosphere. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Conceptest At extremely low temperatures the thin polyethylene fabric (0. 002 inches

The Atmosphere Conceptest At extremely low temperatures the thin polyethylene fabric (0. 002 inches thick) that made up the balloon carrying Joe Kittinger’s capsule would have become nearly brittle. Any small flaws in the fabric could have caused the balloon to spring a leak and deflate. At what location during the ascent would the risk of this potential danger have been most acute? a) Lower troposphere b) Upper troposphere c) Middle stratosphere The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere Mesosphere: Decreasing air temperatures that reach a minimum

Structure and Processes of the Atmosphere Mesosphere: Decreasing air temperatures that reach a minimum of 139°F! Temperature minimum at the mesopause. Temperature decreases due to fewer and fewer ozone molecules to absorb solar UV radiation. Very little oxygen and nitrogen. Sufficient gases to burn up incoming debris. Most near earth objects burn up in this layer. The Good Earth/Chapter 14: The Atmosphere

Structure and Processes of the Atmosphere Thermosphere: Increasing air temperature up to 1, 830°F

Structure and Processes of the Atmosphere Thermosphere: Increasing air temperature up to 1, 830°F due to solar radiation! Blocks most of the harmful cosmic radiation (x-rays, gamma rays, some UV). Very few gas molecules – heat energy is actually low. Gases here are ionized (broken into constituent ions as solar radiation strips them of electrons). Ionized gases cause Auroras (interaction near the magnetic poles of electrons and protons from the sun). The Good Earth/Chapter 14: The Atmosphere

Go back to the Table of Contents Go to the next section: Solar Radiation

Go back to the Table of Contents Go to the next section: Solar Radiation and the Atmosphere The Good Earth/Chapter 14: The Atmosphere

Solar Radiation and the Atmosphere Sun emits electromagnetic radiation (EMR) which is described by

Solar Radiation and the Atmosphere Sun emits electromagnetic radiation (EMR) which is described by its wavelength and frequency. The Good Earth/Chapter 14: The Atmosphere

Solar Radiation and the Atmosphere The relative proportions of solar radiation reaching Earth. Infrared

Solar Radiation and the Atmosphere The relative proportions of solar radiation reaching Earth. Infrared and visible light make up more than 90% of solar radiation at Earth’s surface. Human actions or natural events that affect incoming solar radiation may affect life on Earth! The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 5 The ozone hole over Antarctica actually represents a thinning

The Atmosphere Checkpoint 14. 5 The ozone hole over Antarctica actually represents a thinning of the ozone layer. What are the consequences of the loss of ozone? The Good Earth/Chapter 14: The Atmosphere

Solar Radiation and the Atmosphere What happens to EMR that reaches Earth’s surface? •

Solar Radiation and the Atmosphere What happens to EMR that reaches Earth’s surface? • It can be scattered - Can change direction when it hits particles and gas molecules - This is what causes the blue color of the sky – blue light is scattered more easily than other colors. This scattered blue light reaches our eyes, making the sky blue! - Higher in atmosphere, fewer gas molecules, less scattering, sky appears black. • It can be reflected - Incoming radiation can be reflected off gas molecules and returned to space - Can be reflected off surface features - Albedo = reflectivity of a surface (ice is very reflective, forests and water are not) The Good Earth/Chapter 14: The Atmosphere

Solar Radiation and the Atmosphere • Some EMR is absorbed - Interacts with material

Solar Radiation and the Atmosphere • Some EMR is absorbed - Interacts with material in atmosphere and is converted into some other form of energy (heat). - Atmospheric gases absorb certain wavelengths - Thermosphere absorbs short wavelengths (x rays, gamma rays) - Ozone in stratosphere absorbs UV - Water vapor and CO 2 in troposphere absorb infrared Some solar radiation reaches Earth’s surface – and some of this is absorbed by land oceans, warming the planet (about ½ of incoming solar radiation heats Earth). The Good Earth/Chapter 14: The Atmosphere

Solar Radiation and the Atmosphere The Greenhouse Effect • Surfaces on Earth with low

Solar Radiation and the Atmosphere The Greenhouse Effect • Surfaces on Earth with low albedo absorb solar radiation and reradiate it as infrared (long wavelength) radiation. • This long wavelength infrared radiation is then absorbed by greenhouse gases such as water vapor, carbon dioxide, and other trace gases (methane, nitrous oxide) in the troposphere. • This absorption causes the troposphere to warm = the greenhouse effect! • Keeps the Earth a livable ~33°C (91°F) warmer than if there were no greenhouse effect. • Average surface temperature of Earth would be ~0°F without it (as opposed to current average of ~59°F. • Venus, with so much CO 2 in its atmosphere, has a runaway greenhouse effect resulting in surface temperatures of up to 867°F! The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 7 Explain how the temperature of the Earth would vary

The Atmosphere Checkpoint 14. 7 Explain how the temperature of the Earth would vary from its present level if the atmosphere were (1) thicker (2) thinner (3) cloudier (4) composed of twice as much carbon dioxide The Good Earth/Chapter 14: The Atmosphere

Go back to the Table of Contents Go to the next section: The Role

Go back to the Table of Contents Go to the next section: The Role of Water in the Atmosphere The Good Earth/Chapter 14: The Atmosphere

The Role of Water in the Atmosphere Water is the only substance that exists

The Role of Water in the Atmosphere Water is the only substance that exists in all three states on Earth’s surface The atmosphere contains a small portion of the Earth’s water. The volume of water falling as precipitation annually is 30 times greater than the volume of water stored in atmosphere at any given time. Water is constantly cycled through the atmosphere. Conversion of water from one state to another transfers energy throughout The Good Earth/Chapter 14: The Atmosphere the troposphere.

The Role of Water in the Atmosphere Water molecules are dipolar = opposite charges

The Role of Water in the Atmosphere Water molecules are dipolar = opposite charges on each end of the molecule (net partial negative charge on oxygen atom and net partial positive charge on one hydrogen atom). States of water are defined by the distance between water molecules and their degree of motion: Solid (Ice) – closely spaced, move less, more ordered Liquid (water) – small groups of molecules are attached, rapid movement creates some disorder Gas (vapor) – individual molecules, move very rapidly and therefore don’t attract and join, very disordered The Good Earth/Chapter 14: The Atmosphere

The Role of Water in the Atmosphere Changes of state are accompanied by absorption

The Role of Water in the Atmosphere Changes of state are accompanied by absorption or release of heat Latent heat = the amount of heat absorbed or released as water changes state. Heat is absorbed during melting, evaporation, or sublimation (solid to gas). Heat is released during freezing, condensation, or deposition (gas to solid). Much morel latent heat is released or absorbed during changes between liquid and gaseous states than during changes between solid and liquid states. The Good Earth/Chapter 14: The Atmosphere

The Role of Water in the Atmosphere Evaporation and condensation are extremely important. They

The Role of Water in the Atmosphere Evaporation and condensation are extremely important. They occur over large areas. They contribute to weather phenomena and redistribution of heat in the atmosphere. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Conceptest Your body feels cooler when you step out of a warm

The Atmosphere Conceptest Your body feels cooler when you step out of a warm shower because a) water evaporates on your skin b) water condenses on your skin c) water evaporates from the surrounding air d) water condenses in the surrounding air The Good Earth/Chapter 14: The Atmosphere

The Role of Water in the Atmosphere Humidity = the amount of moisture in

The Role of Water in the Atmosphere Humidity = the amount of moisture in the air. Determined by evaporation and condensation. Hot and humid go together – warm air is more able to hold moisture than cold air. Air is saturated when it can hold no more water vapor at a given temperature. Absolute humidity = mass of water (g) in a volume of air (m 3). Relative humidity = amount of water vapor in air compared to maximum mass of water vapor the air could hold if saturated. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Conceptest Measurements reveal that a cubic meter of air at 12°C actually

The Atmosphere Conceptest Measurements reveal that a cubic meter of air at 12°C actually holds 6 grams of water. What happens if the temperature of the air increases? Explain your answer. (refer to equation on p. 402) a) Absolute and relative humidity both increase. b) Absolute humidity increases and relative humidity remains constant. c) Absolute and relative humidity both decrease. d) Absolute humidity remains constant and relative humidity decreases. The Good Earth/Chapter 14: The Atmosphere

The Role of Water in the Atmosphere When cold air moves over warm water,

The Role of Water in the Atmosphere When cold air moves over warm water, some of the warm water evaporates (steam fog). When warm air moves over cold water, the air cools. Dew Point = temperature air must reach in order to become saturated. Condensation occurs when the relative humidity of air increases enough that the air becomes saturated with moisture. Humidity can increase in two ways: Addition of water Decrease in temperature The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 12 1. Explain why people can see their breath on

The Atmosphere Checkpoint 14. 12 1. Explain why people can see their breath on a cold winter’s day, in terms of water changing state and latent heat. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 12 2. Explain why a hair dryer actually dries your

The Atmosphere Checkpoint 14. 12 2. Explain why a hair dryer actually dries your hair rather than leaving you with hot, wet hair. Explain the process taking place. The Good Earth/Chapter 14: The Atmosphere

Go back to the Table of Contents Go to the next section: Air Pressure,

Go back to the Table of Contents Go to the next section: Air Pressure, Condensation, and Precipitation The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation Atmospheric pressure = the pressure exerted by the weight

Air Pressure, Condensation, and Precipitation Atmospheric pressure = the pressure exerted by the weight of an overlying column of air. Air pressure declines with increasing altitude. Air pressure is influenced by air density. Air density measurement of the mass of atoms and molecules of gases per volume of air. Gravity pulls most gases to Earth’s surface. Air density is therefore higher closer to Earth’s surface. 50% of all air lies below 3 miles altitude. The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation Air contracts when cooled, increasing density (molecules occupy smaller

Air Pressure, Condensation, and Precipitation Air contracts when cooled, increasing density (molecules occupy smaller space) and air pressure Air expands when warmed, decreasing density (molecules can spread out) and air pressure Highest air pressures are found in cold regions, lowest air pressures are found in tropical warm environments. Air pressure decreases rapidly at lower altitudes where air density is greatest, and decreases slowly at higher altitudes. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 13 Which of the following images best approximates the distribution

The Atmosphere Checkpoint 14. 13 Which of the following images best approximates the distribution of the two principle gases in the Earth’s atmosphere? The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation Q: Recall Joe Kittinger’s descent: His balloon expanded on

Air Pressure, Condensation, and Precipitation Q: Recall Joe Kittinger’s descent: His balloon expanded on his ascent. Why? A: The air pressure outside was decreasing leading to an expansion of the helium inside the balloon. The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation • Compressed air becomes warmer, expanding air becomes cooler

Air Pressure, Condensation, and Precipitation • Compressed air becomes warmer, expanding air becomes cooler − Tire pressures are typically twice that of the surrounding air. − When you release the air, the air coming out feels colder than the surrounding air – conversion of heat to mechanical energy = net cooling. − This is an adiabatic change – occurs due to a change in pressure with no loss or gain of energy to or from the surrounding air. Example – burn up of a meteor entering atmosphere. Burn up is NOT a result of frictional heating. The incoming meteor slows down as it compresses the gases of the upper atmosphere, causing air temperature around the meteor to rise. The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation • Rising air cools for two reasons: • It

Air Pressure, Condensation, and Precipitation • Rising air cools for two reasons: • It is expanding and cooling due to decreasing air pressure • It is moving farther away from the warm surface of the earth As a parcel of air rises, the total amount of energy present doesn’t change, but it can be used to either maintain a constant temperature OR to work to expand the size of the air parcel. As the air expands – heat is distributed through a larger volume, producing a cooling effect. Dry adiabatic lapse rate = 10°C per 1, 000 m As rising air cools, its relative humidity increases and the air eventually becomes saturated. Precipitation will occur which releases latent heat. This latent heat counterbalances adiabatic cooling which reduces the cooling rate. Wet adiabatic lapse rate = 6°C per 1, 000 m The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation Clouds form when: • Air rises, cools, and water

Air Pressure, Condensation, and Precipitation Clouds form when: • Air rises, cools, and water condenses, AND • Water vapor has a surface to condense onto − Microscopic particles (dust, smoke, salt, pollutants) Clouds are composed of billions of tiny water droplets that eventually combine to form rain, snow, or hail. Heavier cloud droplets fall and collide and combine with other droplets to form raindrops. One raindrop contains ~1 million cloud droplets. Pure water droplets in high clouds can remain liquid down to -38°F. Supercooled water will only freeze if it is agitated or has a surface to freeze on. The Good Earth/Chapter 14: The Atmosphere

Air Pressure, Condensation, and Precipitation Snow forms when: • Clouds reach temperature below -5°C,

Air Pressure, Condensation, and Precipitation Snow forms when: • Clouds reach temperature below -5°C, whereby air needs a little less water vapor to be saturated for ice than for water. − Condensation will preferentially produce ice crystals. − Miniature ice crystals act as condensation surfaces. − These ice crystals act as condensation surfaces and gradually increase in size to form snowflakes. The Good Earth/Chapter 14: The Atmosphere

Go back to the Table of Contents Go to the next section: Clouds and

Go back to the Table of Contents Go to the next section: Clouds and Frontal Systems The Good Earth/Chapter 14: The Atmosphere

Clouds and Frontal Systems Much of the incoming solar radiation is either absorbed by

Clouds and Frontal Systems Much of the incoming solar radiation is either absorbed by clouds or reflected back into space from their surfaces. Clouds can have both a cooling effect (due to reflection of solar radiation) and a warming effect (due to absorption by water vapor, a greenhouse gas) on the Earth’s surface. At present, we don’t know which effect is stronger. The Good Earth/Chapter 14: The Atmosphere

Clouds and Frontal Systems “cirr” = high level with wispy shape “alto” = midlevel

Clouds and Frontal Systems “cirr” = high level with wispy shape “alto” = midlevel “cumulus” = heap shape nimbo or nimbus indicates rain cloud Stratus clouds – sheet like, cover the whole sky Clouds are classified on the basis of their altitude and appearance. The Good Earth/Chapter 14: The Atmosphere

Clouds and Frontal Systems Why does air rise? • Air rises naturally if it

Clouds and Frontal Systems Why does air rise? • Air rises naturally if it is lighter than the surrounding air masses = density (or convection) lifting. • Frontal lifting = two large air masses of different densities meet. Their boundary is a front. The lighter warm air rises above the colder denser air. The Good Earth/Chapter 14: The Atmosphere

Clouds and Frontal Systems Why does air rise? • Orographic lifting = air is

Clouds and Frontal Systems Why does air rise? • Orographic lifting = air is forced to rise over an obstruction such as mountains. • Convergence lifting = collision of two air masses of similar temperature forces some air upward since both air masses cannot occupy the same space. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 17 Classify the clouds in each of the following images:

The Atmosphere Checkpoint 14. 17 Classify the clouds in each of the following images: The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Conceptest On July 2, 1982, truck driver Larry Walters decided to attach

The Atmosphere Conceptest On July 2, 1982, truck driver Larry Walters decided to attach 45 helium-filled weather balloons to a lawn chair and go for a ride. Lawn Chair Larry rose to an altitude of nearly 5 km (16, 000 ft). The high elevations and lack of oxygen made him dizzy, so he decided it was time to deploy his principal altitude control device, a pellet gun. He shot out several balloons and descended back to Earth. Which process was most significant in Lawn Chair Larry’s balloon ride? Explain your reasoning. a. Density lifting b. Orographic lifting c. Convergence lifting d. Frontal lifting The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Conceptest In the following landscape, how would the amount of rainfall change

The Atmosphere Conceptest In the following landscape, how would the amount of rainfall change at location X if the mountain eroded down to the dashed line? a. Rainfall would increase. b. Rainfall would decrease. c. Rainfall would stay the same. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 19 Use the information from the chapter to explain: 1.

The Atmosphere Checkpoint 14. 19 Use the information from the chapter to explain: 1. Which air lifting mechanism dominates where you live? 2. Which states might provide examples of the four airlifting mechanisms? The Good Earth/Chapter 14: The Atmosphere

Go back to the Table of Contents Go to the next section: Winds The

Go back to the Table of Contents Go to the next section: Winds The Good Earth/Chapter 14: The Atmosphere

Winds Wind = horizontal movement of air that arises from differences in air pressure.

Winds Wind = horizontal movement of air that arises from differences in air pressure. Air flows from areas of high pressure to areas of low pressure. Wind is characterized by its speed and direction. Direction refers to the direction from which the wind originates. Isobar = line of constant air pressure. The Good Earth/Chapter 14: The Atmosphere

Winds Pressure gradient = magnitude of the change in pressure between two points divided

Winds Pressure gradient = magnitude of the change in pressure between two points divided by the distance between the two points. The greater the contrast in pressure, the steeper the gradient and the faster the winds. The closer together the isobars, the steeper the gradient and the faster the winds. The Good Earth/Chapter 14: The Atmosphere

Winds • Due to the Coriolis effect, winds are deflected to the right of

Winds • Due to the Coriolis effect, winds are deflected to the right of their course in the Northern Hemisphere. • Eventually, pressure gradient balances Coriolis effect and winds move parallel to isobars (geostrophic winds). • Winds blowing near Earth’s surface are slowed by frictional drag from the surface. - Friction is most dramatic over rugged surfaces. The Good Earth/Chapter 14: The Atmosphere

Winds Cyclone and anticyclone. Anti-cyclone Cyclone a. Winds converge in low pressure systems creating

Winds Cyclone and anticyclone. Anti-cyclone Cyclone a. Winds converge in low pressure systems creating a counter clockwise airflow at the surface. b. Winds diverge in high pressure systems creating a clockwise airflow at the surface. The Good Earth/Chapter 14: The Atmosphere

The Atmosphere Checkpoint 14. 23 Use the Venn diagram provided to compare and contrast

The Atmosphere Checkpoint 14. 23 Use the Venn diagram provided to compare and contrast the features of atmospheric circulation and the characteristics of oceanic circulation described in chapter 13. Write the numbers of features unique to either group in the larger areas of circles; note features they share in the overlap area. Identify at least 8 features. 1. 2. 3. 4. 5. 6. 7. 8. The Good Earth/Chapter 14: The Atmosphere

The End Go back to the Table of Contents The Good Earth/Chapter 14: The

The End Go back to the Table of Contents The Good Earth/Chapter 14: The Atmosphere