E N D
“I love to swim. One time I was at a beach in the summer. I was swimming for a long time. I got out to eat and dried off in about half an hour. Then I went swimming again and it clouded over. I got out of the water and it took about an hour to dry off this time. I found this very interesting. “ PLANET DIARY 2: Amanda’s Blog What would cause such a difference in drying time? Use complete sentences.
UNIT 3: MOVEMENT IN THE ATMOSPHERE Text references: pgs. 16-19 and pgs. 22-25;
Atmospheric Energy 1. Nearly all the energy in the atmosphere comes from the Sun in the form of Electromagnetic Waves which can easily move through the vacuum of space.
2. Three forms of the sun’s energy come through the atmosphere and have an effect on our atmosphere and weather. They are: Visible light Ultraviolet radiation Infrared radiation
These different electromagnetic waves are identified by their wavelengths
2A: Visible Light……… is the only EM wave that humans can see. We see this light as colors of the rainbow. Each has a different wavelength. Violet is the shortest and red is the longest. When all the waves are seen together-we see white light. Almost all of this light reaches through the troposphere.
2b Ultraviolet radiation The sun emits different wavelengths of ultraviolet radiation. UVA, UVB, and UVC. UVB and C are very bad for living things. Most is absorbed by the ozone layer in the stratosphere. Ozone is our protector! http://www.uvdi.com UV is what makes us sunburn and causes mostskin cancer.
2c. Infrared Radiation (think HEAT) • Has less energy than visible light • Usually warms the materials that absorb it • Absorbed by greenhouse gases in the troposphere • Greenhouse Gases are mixed layers of CO2, methane, water vapor , nitrous oxide and other gases whichabsorb and emit infrared radiation creating the greenhouse effect (a warming of the Earth)
The sun is not the only thing the gives off IR. This is an infrared image of a jeep with its engine running. White is hottest!
3. Two things happen to the Sun’s energy when it reaches the atmosphere. reflected (radiated)-30% total(land 4%; clouds 20%; atmosphere 6%) Absorbed-51% by land; 19% by atmosphere and clouds ** some is scattered while it is in the atmosphere-shorter wavelengths like violet and blue scatter easily this is why the sky looks so blue.
1. Energy from the Sun reaches Earth as _______________________. 2. List three forms of energy from the Sun. 3. Almost all of which type of radiation of radiation from the Sun reaches the troposphere? 4. What happens to most of the sunlight that reaches Earth? 5. How might life on Earth be different without the Greenhouse Effect? Journal AE-1
B. Energy Transfer 2. Thermal Energy-total amount of energy inside something 1. All molecules are in constant motion due to the energy they have in them. The more they have-the faster the y move.
3. We use a thermometer to measure temperature on two common scales: • Metric uses Celsius • USA uses Fahrenheit • (Both named after the scientist that came up with the measurements.) 100 degrees C 212 degrees F (boiling) 0 degrees C 32 degrees F (freezing)
4. Once energyenters our atmosphere, it can be transferred 3 ways. Turn to Page 18 in your text books and draw that diagram in your notes.
4a. Radiation Requires no substance to travel from one place to another. It can move through the vacuum of space . Energy from the sun comes to us through radiation.
4b Conduction http://cache.eb.com/ • The transfer of heat by DIRECT contact between objects or particles. • Example: You walk on a hot sidewalk barefooted and your feet get hot. The heat is moving from the atoms of the sidewalk to your feet.
Example: The layer of air above the earth is warmed by conduction (the transfer of heat by contact) molecule by molecule from the hot earth to the layer of air touching the sand where it then radiates through the air. The heat is also conducted to your feet when you walk on the beach.
4c Convection 1. Convectionoccurs when heat is transferred by the movement of molecules through a substance-usually a liquid or gas. The heat is carried from one place to another by a convection current.
2. Cool air is more dense than warm air so it sinks pushing warm air up. It is a constant cycle. For example: The air at the equator is constantly rising because it is warm and sinking at the poles because they are cold.
Heat warms the atmosphere best when it is in the form ofconvection currents. Convection currents form when heated air expands, becomes lighter, and rises. The heat is carried upward. This is convection! It also happens with liquids.
Conductors Insulators
2 1 3 Warm-up AE-2: Identify and describe these forms of energy transfer.
What type of heat transfer could keep the paper in the air? Make a rough sketch with arrows to help explain your answer. Paper
A. Air Pollution-Harmfulmaterials that are added to the air • It can be moved around by wind • Types • Gases-carbon monoxide, methane, ozone, sulfide oxide, nitrogen oxide • Particulates-solids like dust, pollen, etc. D. Human Activities in the Atmosphere
Sources of Pollution • Human • Fossil Fuels-fuels from the remains of animals and plants • Smog-combination of smoke and fog; bad in big cities • Farming: fertilizers and pesticides • Construction • Factories • Natural-volcanoes, forest fires, dust, dirt, pollen
It can irritate the eyes, nose, throat and lungs • It can make it very hard to breath • It can cause lung damage • It can stick to surfaces and cause damage to plants buildings and other objects B. Effects of Pollution
1. Humans are increasing these gases by using fossils fuels, adding fertilizer to crops and waste disposal (animals and landfills) • Carbon dioxide levels are increasing • We can reduce these gases by using automobiles less, live in houses that use less energy and use energy-efficient appliances C. Greenhouse Gases