2013 Unit Organizer Heating of the Earth’s Atmosphere SOL 6.2 Previous learning: Energy Unit Schedule Current Unit: The Heating of the Earth’s Atmosphere How the Earth's atmosphere Heats & Effects Climate Electromagnetic Spectrum Types of Energy Transfer Convection Currents Unit Vocabulary Electromagnetic Spectrum Ultraviolet Visible Light Infrared radiation Radio waves Gamma Waves Earth's Energy Budget Layers of the atmosphere Microwaves Convection Conduction Radiation Convection currents Earth’s Energy Budget Reflect Absorb Greenhouse Effect Climate Climate Unit questions: 1. 2. 3. 4. 5. Future learning: Weather What are the parts of the electromagnetic spectrum and what do the different wavelengths indicate? What are the 3 ways energy can be transferred and what is an example of each? How do convection currents heat the Earth? What is the Earth’s Energy budget and what impact does it have on the Earth’s atmosphere? What effect does the sun have on the Earth’s oceans and climate? Troposphere Stratosphere Mesosphere Thermosphere 1 Heard before… Never heard before… ____________________________________________ Make Up and Characteristics of Atmosphere Notes ____________________________________________ ____________________________________________ 1) Earth is covered by a layer of air called the atmosphere. The atmosphere extends outward for many miles towards outer space. Gravity holds our atmosphere to the earth. Our atmosphere protects the Earth from falling space objects, helps keep the Earth the right temperature, and is weather takes place. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ 2) Air is a mixture of certain gases. It is made of nitrogen, oxygen, argon, carbon dioxide, and small amounts of other gases. Water vapor is water in a gas form. There is only a tiny amount of water vapor in the air. Nitrogen makes up the largest portion of air, while oxygen makes up the 2nd largest portion. The two gases in the air that living things mainly use are carbon dioxide (plants) and oxygen (other living organisms). ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ 3) Our atmosphere has a couple of specific characteristics. First, as you rise through the layers of the atmosphere the air pressure decreases. There is simply less air pressing down the higher you go. A person at the bottom of the mountain has more air pressure while a person at the top of the mountain has less pressure. This is the most basic change that happens in the atmosphere. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ 4) Secondly, as you rise through the atmosphere there are several temperature changes. Label the graph below hot and cold in the different layers. In the lowest layer, troposphere, temperature decreases as altitude increases. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ 2 ____________________________________________ Layers of Atmosphere Notes ____________________________________________ 1)Our atmosphere is the blanket of air or layer of air around our Earth. There are 4 main layer which are classified according to temperature. The 4 main layers are the troposphere, the stratosphere, the mesosphere, and the thermosphere. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ The thermosphere is the outermost layer of our atmosphere. This layer is special for several reasons. First, it is the hottest layer. The molecules of air are very far apart and are not very dense at all. This is because radiation from the sun hits this layer first. The nitrogen and oxygen in the layer change the radiation to heat. Radio waves travel through the lower parts of this layer, while satellites orbit at the tops of this level. The level can extend up to 300 km above sea level but there is no definite end. The molecules of air gradually thin out until there is nothing left. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ The mesosphere reaches from 50 km to 80km above the Earth's surface. It's air is less dense then the two lower layers. It is the coldest layer-more the -100 F. This is the layer where most meteors burn up. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ The stratosphere rises from the troposphere to about 50 km above the Earth's surface. This layer is unique because the temperature starts out very cold but then gets warmer near the top because the healthy layer of ozone lies here. The ozone layer absorbs radiation from the sun and protects us from harmful ultraviolet radiation. The stratosphere is less dense then the troposphere. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ The layer closest to the Earth's surface is the troposphere. This layer is the thinnest-9-12 km thick. This layer is the most dense and were all the Earth's weather takes place. As you rise into the troposphere several things happen. First, the temperature gets colder. Second, the air becomes less dense and it is harder to breathe. Finally, there is less air pressure because there is not as much air pressing down from higher levels as there would be at sea level. ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ ____________________________________________ 3 4 Electromagnetic Spectrum Notes 1) Our atmosphere receives most of its energy from the sun. This energy travels in wave from the sun called electromagnetic waves, a form of energy that can travel through space. The direct transfer of energy by electromagnetic waves is called radiation. 2) A wave has several parts. A single rise or depression in a series of waves is a pulse. Any two consecutive pulses, one a rise and the other a depression, make up a wave. The high point of a wave is the crest and the low point is the trough. Wavelength is the distance between two waves and can be measured in crest to crest or trough to trough. Electromagnetic Spectrum Parts include: 3) Visible Light is a mixture of all the colors that you see in the rainbow. The different colors are the results of different wavelengths of visible light. Red and orange light have the longest wavelengths. Blue and violet have shorter wavelengths. 4) Infrared radiation is a form of energy with wavelengths that are longer then red light. Infrared radiation is not visible, but can be felt as HEAT. It is emitted as heat and absorbed by cool bodies. Heat lamps used to keep food warm in restaurants give off both visible red light and invisible infrared radiation. 5) The sun also gives off ultraviolet radiation, which has wavelengths shorter then violet light. Ultraviolet radiation can’t be seen but our skin is very sensitive to it. It can cause sunburn, eye damage, and skin cancers. 6) Electromagnetic energy from the sun can be either absorbed or reflected. Clouds, the ground, water, and gasses absorb or soak up energy from the sun. Clouds, the ground, water and gasses also reflect or throw back the suns energy. 5 6 7 __________________________________________ Radiation, Convection, and Conduction Notes __________________________________________ __________________________________________ 1) Energy transferred through empty space by electromagnetic waves is called radiation. When you feel the sun’s rays on your face or the heat from a campfire that is radiation. The Earth’s surface is heated by radiation. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 2) Conduction is the transfer of heat from a warmer object to a cooler object through direct contact. This is why just the tip of a fire poker becomes hot when just the tip is left in the fire or why ice held in your hand will melt. Within the atmosphere, conduction is only important in a very thin layer of air that is touching the surface of the Earth. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 3) Convection, on the other hand is the process of heat distribution within a fluid or gas. This happens through the movement of the fluid or gas. Convection is an important process in our atmosphere. First air near the ground is warmed through conduction and becomes less dense and rises. Next, convection moves that warm air upward. Finally, it rises it becomes cooler and more dense and sinks back towards the ground. The movement of heat in our atmosphere causes temperatures to change, winds to blow, and rain to fall. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 8 9 10 __________________________________________ Convection Currents Notes __________________________________________ 1. Radiation, conduction, and convection work together to heat the bottom layer of the atmosphere (troposphere). __________________________________________ __________________________________________ 2. The first step to warm the Earth’s atmosphere is that some of the sun’s electromagnetic energy moves from the sun is absorbed by the surface of the Earth (ground & water) through radiation. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 3. The 2nd step in the atmosphere’s convection current process is that the now warmed surface of the Earth heats the first few feet of air above the Earth’s surface through conduction. The air is directly touching the surface of the Earth. The air closest to the ground is usually the warmest. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 4. Next, because warm air is less dense it begins to rise and move the heated air molecules with them. The molecules have more energy so they begin to move and bump into each other and transferring there heat through convection. Convection causes most of the heating of the bottom of our atmosphere. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 5. As the air moves farther apart it begins to cool __________________________________________ higher in the atmosphere and become denser. Cooler, denser air sinks back down to the surface of __________________________________________ the Earth. The convection current cycle then __________________________________________ starts again with the air being warmed near the surface of the Earth. __________________________________________ __________________________________________ __________________________________________ _________________________________________ 11 12 __________________________________________ Earth’s Energy Budget Notes __________________________________________ (1) The Earth’s energy budget is a measure of how the Earth uses the incoming solar energy. Of all the solar energy that reaches the out layers of the Earth’s atmosphere, only about half of it reaches the Earth’s surface. Once the sun’s energy enters the atmosphere, it can be absorbed, reflected, or scattered. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ (2) Some of the energy is reflected. The clouds, the ground, water, dust, and water vapor reflect solar energy coming into the Earth’s atmosphere. About 4% of the sun’s energy is reflected right back into space. Sometimes energy can be reflected but then absorbed by the clouds etc. the 2nd time around. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ (3) Some energy is absorbed-soaked up- by the ozone layer, water vapor and dust. Clouds can also absorb the energy. Some of the energy is scattered, or spread out in all directions. That is why the sky appears blue because that part of the electromagnetic spectrum is scattered more then the other colors. Energy that is absorbed into the ground then helps to heat air closest to the ground. The light energy returns to the atmosphere as heat energy and escapes from the Earth’s atmosphere. When that happens the energy budget is a balanced budget. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ ________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ _________________________________________ 13 __________________________________________ Greenhouse Effect Notes __________________________________________ __________________________________________ 1) Incoming solar radiation from the sun is in close balance with the energy that leaves the atmosphere; otherwise the Earth would heat up or cool down. Some gases in our atmosphere trap heat which is called the greenhouse effect. They work like the glass roof of a greenhouse, trapping heat near the Earth’s surface. Without them the Earth would be too cold. With too much of them, Earth would be too hot. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 2) Water vapor, carbon dioxide, and methane are all greenhouse gases. These gases come from several places. Humans burning fossil fuels, the car emissions, and the burning of wood all cause greenhouse gases. Another cause of an increase in carbon dioxide is the cutting down of rainforests. Tree and plants use CO2 to make food. They replace it with oxygen. With fewer trees, more carbon dioxide remains in the air. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 3) If the air heats up too much, Earth’s climate will change. Polar ice might melt and sea levels rise. Coastal areas would flood. Areas that grow many crops might become to dry. Global warming, a gradual increase in the Earth’s temperature, could also be a possible result. Our weather would also be affected because there would be warmer bodies of water, which would increase the number of hurricanes. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 4) Global warming has been neither proven nor disproven. Some scientists say that the gradual increase in temperature in a normal fluctuation in the Earth’s climate that has always occurred. Other scientists say that the increase is too rapid and is a result of human activity. __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ __________________________________________ 14 15 Sun → _________________ Climate, the sun, and our oceans 1. The sun has yet another affect on our Earth. By heating the oceans the sun is partly responsible for the climate on Earth. Climate is the pattern of temperature and precipitation typical of an area over a long period of time. _________ = pattern of temperature and precipitation over time Sun’s affect on oceans/climate: 2. Water is able to absorb heat energy without showing relatively large changes in temperature. The oceans and other large bodies of water act to moderate the Earth’s climate of areas nearby to oceans by absorbing heat from the sun in the summer and then slowly releasing that heat in the winter. For this reason, the climate near large bodies of water is slightly milder (warmer) then areas without large bodies of water. Water _________ heat from sun Waters ______ slowly in _____ ________ release heat all winter Places near oceans stay_______ b/c of heat released by oceans. The chart below shows the average temperature of regions of VA both close to the ocean and more inland, away from the ocean. Answer the following questions: 1. Which region is warmest in January? Region 2. Which region is warmest in July? 3. Which region is closest to the Atlantic Ocean? 4. Which region is coldest in January? 5. Which region is coldest in July? 6. Which region is farthest from the Atlantic Ocean? 7. What conclusion can we draw? The regions _________ to the ocean stay the warmest in the _________. 16 January July Average Average Temperature Temperature Tidewater Climate Region: includes Virginia's Tidewater & Hampton Roads, the southern Chesapeake Bay and Eastern Shore Regions 35-48 (F) 71-85 (F) Piedmont Climate Region: includes Central Virginia Region 27-47 (F) 68-88 (F) Northern Virginia Climate Region: includes Northern Virginia and 19-42 (F) northern Chesapeake Bay Regions 61-86 (F) Western Mountain Climate Region: includes 27-45 (F) Virginia's Shenandoah Valley Region 65-87 (F) Southwestern Mountain Climate Region: includes Virginia's Southwest Blue 24-44 (F) Ridge Highlands and Heart of Appalachia 60-85 (F) 17 18