Unit 4 Review Guide: Weather Weather: The condition of the atmosphere at a specific time and place. Freezing: To become hardened into ice or into a solid body Deposition: The change in state of matter from gas to solid that occurs with cooling. Melting: The change in state of matter from solid to liquid that occurs with heating. Condensation: The process of changing a gas to a liquid. Sublimation: A change directly from a solid to a gas. Evaporation: The change in state of matter from a liquid to a gas that occurs with heating. Temperature: A measure of the average motion of the molecules. Urban Heat Island Effect: Where big cities are warmer than suburbs because all the blacktop in the city absorbs more energy than the grass in suburbs. Global Warming: Earth s temperatures have gone up by about 1 in the past century due to carbon dioxide. Wind: The horizontal movement of air from high to low pressure. Wind Vane: Tool that allows you to measure wind direction (The arrows point in the direction that the wind is coming from). Wind Sock: Tool that allows you to measure wind direction (The wind sock points in the direction that the wind is blowing). Anemometer: Tool that allows you to measure wind speed (Device with cups). Barometer: Tool that measures air pressure. Humidity: The amount of water in the air (called water vapor). Relative Humidity: The amount of water vapor in the air compared to the amount of water vapor that the temperature can hold. Dew Point: The point at which water condenses out of air.
Saturated: Air that can no longer hold any more water. Orographic Lift: Air that is moving horizontally and it hits a mountain, and gets forced up. Convergence: Two groups of air are moving towards each other, they collide and are pushed up. Frontal Lifting: Cold air moves into warm air and they collide. The warmer less dense air is forced up. Condensation Nuclei: Little specks of dust and dirt that cloud droplets form on. Stratus: Low, layered clouds. Cumulus: Puffy clouds with flat bottoms that grow upward. Cirrus: High, thin clouds Alto: Another word for middle. Nimbo: Another word for rain Precipitation: Water or ice falling from clouds. Rain: Melted Snowflakes. Snow: Ice crystals falling from the clouds. Freezing Rain: Rain that is falling from clouds that hits the cold freezing ground and therefore freezes. Hail: Balls of ice that fall from a cumulonimbus cloud. Air Mass: A large body of air that has similar characteristics of humidity and temperature. Source Region: The place where an air mass forms. Maritime: When an air mass is very humid because it formed over an ocean Continental: When an air mass is very dry because it formed over a continent. Polar: When an air mass is very cold because it formed in the poles. Tropical: When an air mass is very warm because it formed in the tropics. Air Mass Modification: Whenever an air mass moves over an area it changes. Front: A boundary that separates two air masses.
Cold Front: Boundary between advancing cold air from warm air in front of it. Warm Front: Boundary between advancing warm air from cold air in front of it. Stationary Front: Separates two air masses- one warm and one cold, but neither is strong enough to move. Cyclone: Another name for a low pressure system. Anticyclone: Another name for a high pressure system. Severe Weather: Any type of weather that causes danger. Thunderstorms: A storm that causes lightning, thunder, heavy rains/flash flooding and strong winds/hail. Lightning: Updrafts and downdrafts cause friction between the objects, which causes the cloud to be electrically charged. Thunder: Occurs when lightning heats air very rapidly to about 54,000 F and the air quickly expands and then cools and therefore contracts making a loud sound. Tornado: A violent rotating column of air in contact with the ground. Hurricane: A large swirling low pressure system that forms over warm waters. Tropical Storm: Low pressure system with winds at least 39 mph. Saffir-Simpson Scale: Scale from Category 1 to 5 that measures hurricane strengths. Blizzard: Occurs when winds are over 35 mph, temperatures are low, and visibility is less than ¼ of a mile for three hours. Watch: Conditions are favorable for severe weather within the next 36 hours. Warning: Conditions already exist and severe weather will happen in the next 24 hours. Climate: The average weather in a location over a long period of time. Tropical Zone: Climate zone Located between 23.5 N and 23.5 S. Polar Zone: Climate zone that extends from 66.5 all the way to the poles. Temperate Zone: Climate zone located between the tropics and polar zone.
Rain Shadow Effect: A dry region on the surface of the Earth that is leeward or behind a mountain with respect to the prevailing wind direction. Greenhouse Effect: A natural heating process that occurs when certain gases in the atmosphere absorb heat. Practice Problems: 1. On weather maps, there are lines with tiny triangles on one side. This represents- A. Cold air moving in the direction the triangles point B. Cold air moving opposite the direction the triangles point C. Warm air moving in the direction the triangles point D. Warm air moving opposite the direction the triangles point 2. Ocean Evaporation Condensation Which of these would come next in the water cycle? A. Aeration B. Sedimentation C. Deposition D. Precipitation
3. In which of the graphs would the precipitation at ground level most likely be rain?
4. Water vapor is lighter than many atmospheric gases such as oxygen, nitrogen, and carbon dioxide. Why then doesn t water vapor rise above these other gases to a higher level in the atmosphere? A. Water vapor contains other elements that give it weight B. The cool atmosphere condenses the rising water vapor and causes it to fall back to Earth C. The water molecules are attracted to molecules of heavier gases and remain in the lower regions of the atmosphere. D. There is an attraction among the water vapor molecules to hold them together close to the Earth 5. The countries shown here released more CO2 than the rest of the world because these countries have the largest- A. Number of people B. Amount of rainfall C. Number of heavy industries D. Amount of land per person 6. According to the map, Most hurricanes occur where- A. The oceans are warmest B. The landmasses are largest C. The atmosphere is driest D. Areas of greatest population exist
7. Most air from the Pacific Ocean rises and cools as it passes from west to east over the Sierra Nevada Mountains. Once it is over the mountain range, the air descends and warms on the other side. What is the result of the air ascending, then descending over the mountains? A. Desert on the west side of the mountains and heavy rains on the east B. Heavy rains on the west side of the mountains and desert on the east side C. Heavy rains on the west side of the mountains and year-round snow on the eastside D. Desert on the east and west sides of the mountains and heavy rains on top of the mountains 8. According to this map, the mean annual temperature for most of the eastern half of Virginia is between- A. 45 F and 50 F B. 50 F and 55 F C. 55 F and 60 F D. 65 F and 70 F 9. Which of these is important in the formation of clouds? A. The relative length of day and night B. The Coriolis Effect C. The melting of the polar ice caps D. The cooling of air as it rises 10. What is one of the major indications that the Earth s climate has varied over time? A. Land forms carved by glaciers in temperate areas B. Depletion of oxygen in lakes and rivers C. Ocean currents D. Magnetic reversals in layers of rock
11. A rain forest is found at the base of Mt. Kilimanjaro, and the summit is snowcapped. Which of the following would best account for this? A. Temperature differences due to elevation changes B. Climate differences due to seasonal changes C. Differences in precipitation due to formation of a rain shadow D. Climate changes due to changes in latitude 12. Which of these would likely occur as the ice caps melt? A. The Earth would become cooler B. The sea would cover more land C. The rivers would flow more rapidly D. The rain would be more acidic 13. The graph shows the outdoor temperature at a certain location during a 24-hour period. What possible occurrence happened at 2:00 P.M.? A. Daylight-savings time B. Eclipse of the moon C. A solar storm D. Thunderstorm passes 14. On clear nights in late summer and early fall in the Shenandoah Valley, why does ground fog form in the low areas near the Shenandoah River? A. Cool, descending air meets moist air in the low areas near the river B. Cool, moist air ascends from the river to the hilltops C. Warm winds bring moisture from the hills down into the valley D. There is more air pollution in the evenings
15. Based on the above symbols, which of the following represents a wind speed of 30 knots? A. B. C. D. 16. People have tried many methods to artificially produce rain. One method, called cloud seeding, involves airplanes dropping particles of silver iodide onto clouds to help the clouds produce rain droplets. These silver iodide particles act as- A. Hailstones B. Dew Points C. Electrical Charges D. Condensation Nuclei