Science 8 Unit 3 Atmosphere & Oceans Test 1 Review Name: Period: Directions: Please review all learning goals, activities, purposes, and review questions. Also review the “Tornado Formation Timeline” to relate our activities to the formation of Tornadoes and the four scrims for this Unit so far. Answer on separate notebook paper if you are using a packet and staple all work together, or make a Test 1 Review section in your compbook. Learning Goals for Test 1: Learning Goal 1: I can develop and use a model to describe how unequal heating and rotation of the Earth affect the atmosphere and weather. Learning Goal 2: I can use data as evidence to explain how the movement of air masses causes weather changes. Learning Goal 3: I can analyze and interpret data to forecast future weather events and the intensity of events. Activities, Purposes, and Review Questions 1. Our Sun’s Energy: To investigate Earth’s major source of energy, the Sun. a. What is the original source of almost all energy on Earth and how does this energy reach Earth? The Earth’s energy comes from the Sun. The sun’s energy reaches us through radiation, which is the transfer of energy through electromagnetic waves. b. What three major types of light energy is Solar energy composed of? What does each of these types of light do for Earth? The light from the Sun contains a variety of light types, but the three major types of light are infrared, visible light, and ultraviolet. Infrared light is felt as “heat”, red color light. Visible light allows us to see different colors, aka “white light”. Ultraviolet light (UV) is light that is associated with skin cancer because it can cause mutations in surface cells. Seen as purple or “black light”. 2. CE 3.1 Heating and Cooling: To investigate how energy from the Sun heats different surfaces on Earth. a. Review the heating and cooling of surface materials for scientific method components: (ie: manipulated variable, controlled variables, responding variable, etc.) b. Which heated faster: soil or water? Explain how this relates to Earth’s surfaces. Soil heated faster than water. This is similar to land during the daytime, which heats up faster than water such as lakes and oceans. c. Which material held its heat the longest? Does this represent day or night? Water retained (kept) its heat longer than land. So at night, the land and air above land cool down, while the ocean and air above ocean stay the same temperature. 3. The Atmosphere: To investigate the structure and function of Earth’s atmosphere. a. What are the 5 layers of our atmosphere (in order)? What layer is where most of Earth’s weather takes place? In order from the surface of the Earth, moving outwards towards space: 1. Troposphere: 0-12km thick, contains 75% of gases on Earth, where weather occurs, where convection happens, where we live! 2. Stratosphere: 12-50km thick; contains ozone layer that acts as a shield, dry and has a lower density. 3. Mesosphere: 50-80km thick; coldest region, protects us from meteoroids, absorbs photons, reflects radio waves 4. Thermosphere: 80-500km thick; air is very thin, very high temperatures (over 2000 degrees Celsius) 5. Exosphere: 500-1000km or more; free moving charged particles, where satellites are. b. What is the greenhouse effect? What gasses in our atmosphere are responsible for the greenhouse effect? What other gasses are present in the atmosphere? Three greenhouse effect is warming of the Earth due to gases (Carbon Dioxide, Water Vapor) trapping heat in the atmosphere. Other gases in the atmosphere are Nitrogen, Oxygen, and Argon. c. What role does the sun play in the weather on earth? The sun heats the troposphere from above. Surfaces either absorb or reflect energy from below. This causes changes in the temperature, pressure, and humidity of the troposphere, allowing air in the troposphere to experience weather (wind, clouds, precipitation, etc.) d. Describe the role of latitude in unequal heating. At the equator, radiation from the sun is direct. At the poles, incoming radiation is spread out and must pass through more overall atmosphere. e. What causes seasons on Earth and how does this affect weather? The Earth is tilted on its axis 23.5 degrees, which means one hemisphere will receive more solar energy every day if that hemisphere is tilted towards the Sun (summer = warmer weather). The other hemisphere, which will be tilted away, will receive less Solar energy every day (winter = colder weather). f. How does gravity affect the density of particles in Earth’s atmosphere? Surface gravity is stronger the closer you are to the surface of Earth. This pulls particles closer together, making the particles more dense. Therefore, density of particles increases as altitude decreases. 4. CE 4.1 Inv. Air Temperature: To investigate the effect of surface temperature on the air temperature above the surface. a. How does air temperature change, and air move, above a warm surface as well as above a cold surface? Air that is above a warm surface will warm up and rise. Air that is above a cold surface will cool down and sink. Remember, heat transfer occurs from the hot area to the cold area. b. What is an air mass? c. How is the temperature and humidity of air affected by the surface the air is above? An air mass is a large body of air that takes on the temperature and humidity of the surface the air is above. 5. CE 5.1 Inv. Effects of Colliding Air Masses: To investigate the movement of air masses when similar and different air masses meet. a. Describe convection and a convection current. Convection is the movement of fluid (air or water) as a result of density differences. A convection current is formed when different density materials interact, creating a cycle of rising and sinking material. b. What happens when a warm air mass meets a cooler air mass? (hint: convection currents) A warm, less dense air mass will rise and be replaced as the cooler, denser air mass moves into the space left behind by the warm air rising. c. Describe the difference between a land breeze and a sea breeze. d. What factor(s) causes the difference between land breezes and sea breezes? A sea breeze occurs when land heats up faster than water during the day. This heats up the air above land, making the air less dense. The air rises. Air over water cools, becomes dense, and sinks. The cooler, dense ocean air moves into land as a sea breeze. A land breeze occurs when at night (or on a cold day), when the air above land cools faster than the air above the ocean. The land air sinks and moves from land out to sea to form a land breeze. Therefore, the main factor that causes the difference between land breezes and sea breezes is uneven/unequal heating of Earth’s surfaces – mainly that land heats up and cools down faster than water – causing the air above land to heat up and cool down faster than air above water. 6. CE 6.1 Temperature, Pressure, & Cloud Formation: a. Describe the role of the water cycle in weather. Evaporation, condensation, and precipitation are key parts of the water cycle. Evaporation occurs as water gains heat energy and changes from a liquid form to a gas form (water vapor). Condensation occurs as water loses heat energy and changes from a gas form (water vapor) to a liquid form. Precipitation will occur when clouds collect enough water vapor. b. Describe the general relationship between temperature and pressure in our atmosphere. The general relationship between temperature and pressure is that as temperature decreases, pressure also decreases. c. Describe how temperature and pressure change at different altitudes. How does this affect the density of air? As altitude increases, temperature and pressure decrease. Important: although pressure and temperature are related, density differences caused by temperature and pressure are not the same. Higher temperatures and lower pressure are related to lower density. Lower temperature and higher pressure are related to higher density. Example 1: Warm, dry air is low pressure, but high temperature. Example 2: High pressure air (particles are close together) can be cold and dense, even though we think of high pressure as clear weather. High pressure air can also be warm, humid air (lots of water particles in the air = higher pressure). d. How do clouds form? What conditions are needed? What “materials” are necessary? (be specific about temperatures, pressure, and the steps/requirements involved to form a cloud) For clouds to form, first we need evaporation to put water vapor into the air, and then we need condensation to change that water vapor back into liquid water that attaches to dust particles, forming clouds. So first, higher temperatures are needed to add energy and increase evaporation. This step happens during the time (hours, days, weeks, months) leading up to cloud formation. Next, lower temperatures are needed, with less energy, to allow for condensation. Therefore, the more evaporation you have = the more possible condensation. Bigger differences in temperature = bigger clouds (think about tornadoes here and the huge storm clouds that are associated). 7. Weather Fronts & Weather Mapping: To investigate weather fronts and weather mapping. a. What is a weather front? b. How are different weather fronts represented on a weather map? c. In what direction is the weather moving across the U.S.? Explain why weather moves this way. I have combined responses for #7 & #8 (see below) 8. Weather Cycler: (1) Read a weather map and explain it to others. (2) Use a weather map to describe the weather at different places. (2) Make connections between concepts that affect weather. a. Review how to read a weather map and predict what weather will be at a location based on this weather map. Focus on weather conditions such as temperature, pressure, clouds, precipitation, and weather fronts. Example weather forecast (there are many different things going on that you could describe here – I will give a couple as an example): A warm front is moving into the Northern Mid-West region of the U.S. I know this because the red semi-circles indicate a warm front and show me the direction that the front is traveling (west to east). This means that warm air will slowly move over cooler air and bring a period of light, steady rain and warmer temperatures to that region. The green area over Washington State indicates light rain/drizzle in that region of the U.S. I also notice that there is a High Pressure area over NorthEast Texas – indicated by the capital H. This means there is higher air pressure and no cloud formation. I would expect there to be clear conditions – although it might not necessarily be hot or dry. Weather typically moves from West to East across the United States because air masses move West to East. Air masses can also be pushed up down from the North (Canada) or up from the South (Gulf of Mexico). See powerpoint for detailed notes on weather fronts. A weather front is the boundary between different masses of air (temperature, humidity, and pressure differences) with the front named after the air mass that is moving into the region. Changes in weather occur along this boundary as air masses meet. Weather fronts are associated with different types of cloud formation and precipitation. 9. CE 2.1 Modeling a Vortex: To investigate a vortex and its role during rotating storms, such as a tornado. a. What is a vortex and what causes it? b. Describe the characteristics of weather events such as hurricanes, tornadoes, and thunderstorms. What is similar about these weather events? What is different? A vortex is a mass of rotating air or water. Vortices are associated with the rotating wind in a hurricane or tornado. The Coriolis Effect, due to Earth’s rotation, gives these vortices their counter-clockwise spin. Differences in weather events such as hurricanes, tornadoes, and thunderstorms should be described on the last page of your packet. Access the online textbook to complete the reading if necessary. Email me if you have any questions – good luck studying!! Vocabulary: Instructions: Review vocabulary terms and definitions. You can choose which terms to define. Focus on the terms that you struggle with rather than trying to complete all terms.