Earth’s Atmosphere

Energy Transfer in the Atmosphere Part Two

Key Concepts 1: How does energy transfer from the Sun to the Earth and to the atmosphere? 2: How are air circulation patterns within the atmosphere created?

Vocabulary Radiation Thermal Energy Conduction Convection Latent Heat Stability Temperature Inversion

Energy from the Sun The Sun’s energy reaches Earth through the process of radiation. Radiation: is the transfer of energy by electromagnetic waves The radiant energy from the Sun consists of: 1: Visible Light 2: Ultraviolet Light 3: Infrared Radiation Thesuiteworld.com

Visible Light Most of the radiation that the Sun gives off is visible light. Visible Light: light that you can see Visible light passes through the atmosphere to Earth’s surface, where it is converted to thermal energy (heat). Thermal Energy: energy that comes from heat.

Ultraviolet Light (UV) Ultraviolet (UV) light has shorter wavelengths than visible light. Ultraviolet light is responsible for causing our sunburns Though some ultraviolet waves from the Sun penetrate Earth's atmosphere, most of them are blocked from entering by various gases like Ozone. Airqulaity.weather.gov

Infrared Radiation Earth absorbs energy from the Sun, then radiates it back as infrared energy to the atmosphere. Infrared waves = heat rays. Infrared radiation has longer wavelengths than visible light. You can feel infrared radiation as warmth. Sun produces very little infrared radiation compared to visible light and ultraviolet light

Reflection Compare and contrast visible light and ultraviolet light. Must be at least five complete sentences long

Key Concepts 1: How does energy transfer from the Sun to the Earth and to the atmosphere? 2: How are air circulation patterns within the atmosphere created?

Vocabulary Radiation Thermal Energy Conduction Convection Latent Heat Stability Temperature Inversion is the transfer of energy by electromagnetic waves energy that comes from heat

Energy on Earth As the Sun’s energy passes through the atmosphere, some of it is absorbed, or taken in, and some of it is reflected back into space. As a result, not all of the energy coming from the Sun reaches Earth’s surface.

Absorption Gases and particles in the atmosphere absorb about 20% of incoming solar radiation. Oxygen, ozone and water vapor: absorb ultraviolet light from the sun. Water and carbon dioxide: absorb some infrared radiation from the sun. Earth’s atmosphere does not absorb visible light, visible light must be converted to infrared radiation before it can be absorbed. O₂, O₃,H₂O (gas) CO₂, H₂O (liquid)

Demo Heating Things Up

What type of radiation do you think passes most easily through Earth’s atmosphere: ultraviolet light, visible light, or infrared radiation?

Atmospheric gases don’t absorb visible light, but is there something else in the atmosphere that may do this?

Reflection Bright surfaces, especially clouds, reflect radiation as it enters the atmosphere. Clouds and other small particles in the air reflect about 25% of the Sun’s radiation. Land and sea surfaces reflect about 5% of the Sun’s radiation back to the atmosphere.

1: How much total radiation is reflected off materials in the atmosphere and from Earth’s surface? 2: What percentage of incoming radiation is absorbed by gases and particles in the atmosphere? 3: How much incoming radiation actually makes it to Earth’s surface to be absorbed?

If 30% of the incoming radiation reflects back into space, and the atmosphere absorbs 20%, Therefore, only 50% of incoming solar radiation reaches Earth surface where it is absorbed.

Radiation Balance Land, trees, and the ocean absorb and emit solar radiation, mainly in the form of infrared radiation. This radiation balance maintains an overall temperature on Earth. Amount of radiation incoming from the Sun Amount of radiation going out from Earth = How does the graph indicate that the amount of radiation reaching Earth equals the amount of radiation given off by Earth?

What is a Greenhouse? A greenhouse is a house made of glass. Sunlight shines in and warms the plants and air inside. So during the daylight hours, it gets warmer and warmer inside a greenhouse, and stays pretty warm at night too.

How is Earth a Greenhouse? During the day, the Sun shines through the atmosphere. Earth's surface warms up in the sunlight. At night, Earth's surface cools, releasing the heat back into the air. Gases that trap infrared radiation best are water vapor (H₂O), carbon dioxide (CO₂) and methane (CH₄).

Is it warm here or is it just me…. Greenhouse Effect: the process by which radiation from Earth’s atmosphere warms its surface to a temperature above what it would be normally. If the atmosphere causes too much greenhouse effect, Earth just gets warmer and warmer. This is what is happening now.

Reflection How can greenhouse gases cause a heat surplus? Must be at least five complete sentences long

Vocabulary Radiation Thermal Energy Conduction Convection Latent Heat Stability Temperature Inversion is the transfer of energy by electromagnetic waves energy that comes from heat

Thermal Energy Transfer There are three type of thermal energy transfer that occur between the Sun, atmosphere and Earth. Energy is transferred on Earth and in the atmosphere through: 1: radiation 2: conduction 3: convection Thermal energy always moves from an object with a higher temperature to an object with a lower temperature HIGHER LOWER

Radiation Review Radiation: is the transfer of energy by electromagnetic waves The radiant energy from the Sun consists of: 1: Visible Light 2: Ultraviolet Light 3: Infrared Radiation Thesuiteworld.com

Practically all of the energy that reaches the earth comes from the sun and is intercepted first by the atmosphere. A small part is directly absorbed, by gases such as ozone and water vapor. Some energy is also reflected back to space by clouds and the earth's surface.

Conduction Conduction: Transfer of energy by the collisions between particles of matter When the spoon (substance) is heated, its particles gain energy and vibrate more vigorously. The particles bump into nearby particles and make them vibrate more. Thermal energy in the vibrating particles or molecules is passed on to nearby particles in a process called conduction.

Conduction

Conduction in the Atmosphere Since air is a poor conductor, most energy transfer by conduction occurs right at the earth's surface. Good Conductors Metals Poor Conductors Wood Air Water VS. During the day, solar radiation heats the ground, which heats the air next to it by conduction. At night, the ground cools and the cold ground conducts heat away from the adjacent air.

Convection When the particles in liquids and gases get warm, they become less dense, take up more space, and they rise. The space is quickly replaced by cooler particles that are more dense, because they are heavier and sink. Thermal energy is transferred from hot places to cold places (air or liquid) by convection. Convection: Transfer of energy by the movement of particles within matter.

Convection in the Atmosphere Convection occurs in fluids such as water and air, which move freely. As molecules of air close to Earth’s surface are heated by conduction, 1:They spread apart, and air becomes less dense. 2: Less dense air rises, transferring thermal energy to higher altitudes. 3: Colder denser air sinks and moves into to replace the space where hot air was. These vertical motions effectively distribute heat and moisture throughout the atmospheric column and contribute to cloud and storm development

Latent Heat Water helps transfer energy from Earth’s surface to the atmosphere through a process called Latent Heat Exchange.

Video - review Conduction, Convection, Radiation

Activity Transferring Energy In your small group, work together to write a short skit of a situation in which heat is transferred through conduction, convection and radiation. Skits should be no longer than a few minutes and will be preformed in front of the class.

Reflection How does energy transfer from the Sun to the Earth and the atmosphere? Must be at least five complete sentences long

RECAP Circulating Air in the Atmosphere 1: Solar radiation heats the Earth’s surface 2: The heat from the Earth’s surface is transferred through the atmosphere by conduction. 3: When the layer of air receives enough heat through conduction, it expands, becomes less dense and is pushed upward. Colder, denser air sinks under it. 4: Process is repeated over and over because air is constantly moving and circulating Circulating air affects weather and climate around the world by creating local breezes, winds, cyclones, and thunderstorms.

Stability Stability: property of the atmosphere that describes whether circulating air movements will be strong or weak. When air is unstable, circulating motions are strong. When air is stable, circulating motions are weak. You feel a strong wind blowing. What does this tell you about the air’s stability?

Unstable Air = Thunderstorms During unstable conditions, ground-level air is much warmer than higher altitude air. Thunderstorms: 1: Warm air rises rapidly in the atmosphere, it cools to form large, tall clouds. 2: Latent heat, released as water vapor, rapidly changes from a gas to a liquid, creating instability 3: Instability produces a thunderstorm.

Stable Air = Temperature Inversions During a temperature inversion, a layer of cooler air is trapped by a layer of warmer air above it. Temperature inversionTemperature inversion: occurs in the troposphere when temperature increases as altitude increases. Temperature inversions prevent air from mixing and can trap pollution in the air close to Earth’s surface.

Reflection What type of weather do you like best - weather caused by stable air or weather caused by unstable air? Must be at least five complete sentences long.

Reflection How do conditions during a temperature inversion differ from normal conditions? Must be at least five complete sentences long