1. Chapter 7: Atmosphere, Hydrosphere, and Lithosphere Ms. Johnson Foundations

2. Objectives Earth’s surface has three different “spheres”: atmosphere, hydrosphere, and lithosphere. Among the three spheres, energy and matter interact. The sun is the primary source of energy affecting Earth’s surface. Factors, or elements, that make up the state of weather are temperature, air pressure, humidity, wind, clouds, and precipitation. Climate is the average weather that prevails over a large area for a long period of time. Weather maps show the positions of air masses, fronts, and weather elements at many locations. Weather maps aid in weather forecasting. Humans are affected by the atmosphere in their daily lives. Major effects are caused by thunderstorms, hurricanes, tornadoes, and winter storms. Human pollution is changing the atmosphere. About 75% of Earth’s surface is covered by water. The five oceans contain most of the liquid water on Earth’s surface. They are in constant motion due to currents, waves, and tides.

3. Vocabulary Interaction of Spheres Lithosphere Hydrosphere Atmosphere Condensation Nitrogen cycle Oxygen-carbon dioxide cycle The Atmosphere Weather Air temperature Air pressure Humidity Wind Clouds Precipitation Convection Latitude Prevailing winds Climate Large-Scale Weather Systems Air mass High pressure systems Low pressure systems Front Weathering forecasting Interaction of Humans and the Atmosphere Storms Thunderstorms Hurricanes Tornadoes Winter storms Pollutants Smog Acid rain Greenhouse effect Hydrosphere Tides Surface currents Density currents

4. Interaction of Spheres: Energy Exchange Planet Earth consists of 3 main spheres: ▫Lithosphere: a rock sphere ▫Hydrosphere: a water sphere ▫Atmosphere: a gaseous sphere On Earth these three spheres come into contact with one another through the interaction of matter and energy. Lithosphere we talked about in Ch. 5- Earth’s Surface

5. Interaction of Spheres: Composition This pie chart shows the composition of Earth’s atmosphere The interactions between the three spheres replenish gases through cycles, so the percentages are always constant.

6. Interaction of Spheres: Interactive Cycles The sun’s energy powers the water cycle. Water cycle: water moves between Earth’s surface and the atmosphere. Evaporation: occurs when liquid water is changed into water vapor. (L  G) ▫Ex. when a rain puddle dries up on a hot day Condensation: the changing of water vapor into droplets of liquid water. (G  L) ▫Produces fog, dew, and clouds Precipitation: water in the form of rain, snow, sleet, or hail, falling from clouds in the sky. (G  S)

7. Water Cycle

8. Interaction of Spheres: Interactive Cycles Nitrogen cycle: maintains levels of gaseous nitrogen in the air and at the same time provides nitrogen for protein production in plants and animals. Some bacteria aid in removing nitrogen from decaying organic matter and other types return nitrogen back into a gaseous state. Lightning and nitrogen-fixing bacteria remove nitrogen from the air and place it back in the soil.

9. Nitrogen Cycle

10. Interaction of Spheres: Interactive Cycles Oxygen-carbon dioxide cycle: plants absorb carbon dioxide (CO 2 ) and produce oxygen (O 2 ) in the process of photosynthesis. Animals breathe in oxygen, and through the process of respiration, return carbon dioxide to the air.

11. Oxygen-Carbon Dioxide Cycle

12. The Atmosphere: Defining Weather Weather: consists of the conditions of the atmosphere, such as heat, cold, sunshine, rain, snow, clouds, and wind. These conditions change from day to day and from place to place. Energy from the sun is the main cause of these changes.

13. The Atmosphere: Weather Elements The elements that make up weather include: air temperature, air pressure, humidity, wind speed and direction, clouds, and precipitation. Air temperature: the amount of heat in the atmosphere. Air pressure: measured with a barometer, it is the force with which air presses down on Earth’s surface. Affected by temperature and elevation. ▫Higher elevations have less air pressure

14. The Atmosphere: Weather Elements Humidity: the amount of water vapor (gaseous form) present in the air. ▫Warm air can hold more vapor than cold air. ▫Relative humidity is the ratio between the actual amount of water vapor in the air to how much the air can hold (measured with hygrometer) Wind: the movement of air over Earth’s surface. ▫Wind speed is how fast the air is moving (km/hr measured with anemometer) ▫Wind direction is the direction from which the wind is coming (determined with a wind vane)

15. The Atmosphere: Weather Elements Clouds: masses of tiny water droplets or ice crystals suspended in the air. ▫Cloudiness is the amount of clouds that cover the sky (partly cloudy, mostly cloudy, overcast, etc.) Precipitation: water, in any form, falling from clouds in the sky. ▫Rain, snow, sleet, hail, ▫Measured in inches

16. The Atmosphere: The Sun’s Energy The sun is the main source of energy for the atmosphere ▫As the sun heats the Earth, some of that heat energy gets radiated back into the atmosphere The heating of Earth’s surface depends on the nature of the surface. ▫Pavement and sand get hotter than grass Surfaces of the oceans, forests, and deserts heat the air above them differently, producing different air temperatures.

17. The Atmosphere: The Sun’s Energy When air is heated, it becomes less dense, ▫Warm air rises, cool air sinks As air rises or falls, the surrounding air rushes in to replace it, causing air to circulate. Convection: the circulation of air

18. The Atmosphere: The Sun’s Energy Heating the surface also depends on the angle at which the sun’s rays strike the Earth. Near the equator, the sun’s rays are more direct. Since the Earth is curved, the sun’s rays strike away from the equator at a slanting angle. The farther from the equator, the more slated the sun’s rays come in, and the less effectively they heat the surface.

19. The Atmosphere: The Sun’s Energy Latitude: the distance north or south of the equator. Prevailing winds: winds that blow the same direction at a given latitude ▫Ex. In the U.S. the prevailing winds blow from west to east, so they are called the westerlies.

20. The Atmosphere: Climate Climate: the general character of the weather that prevails in an area from season to season and from year to year. Factors that influence climate are latitude, altitude, water, and mountain barriers. ▫As you move away from the equator, the climate tends to get cooler. ▫Higher elevations (height above sea level) are cooler than lower elevations. ▫Land areas close to oceans or lakes have more moderate climates ▫The sides of mountains facing prevailing winds have cooler climates than those not facing the winds

22. Large-Scale Weather Systems: Air Masses Air mass: a large body of air that has uniform temperature and moisture conditions throughout. ▫An air mass forms when air stays over a large area of Earth’s surface and takes on the temperature and moisture characteristics of that area. There are four different surface conditions that affect the formation of the formation of air masses. ▫Cold, dry, warm, moist As an air mass moves, it changes the local weather conditions of the surface below.

23. Large-Scale Weather Systems: Air Masses

24. Large-Scale Weather Systems: High-Pressure and Low-Pressure Systems High-pressure systems: a large area where air is sinking, causing high surface air pressure. ▫The air sinks and wind blows outward from the center, turning clockwise ▫They bring clear skies, dry weather, and gentle winds ▫Shown on a weather map by a H

25. Large-Scale Weather Systems: High-Pressure and Low-Pressure Systems Low-pressure system: a large area where air is rising, causing low surface air pressure. ▫The air rises and winds spiral in towards the center, turning counterclockwise ▫Usually bring cloudy, wet weather with strong, gusty winds ▫Shown on a weather map by a L

26. Large-Scale Weather Systems: Fronts Front: the boundary that forms when one air mass comes into contact with another air mass ▫Sudden conditions occur across a front because the air masses normally differ in temperature, humidity, and density. Cold fronts or warm fronts are produced, depending on how the air masses come together.

27. Large-Scale Weather Systems: Fronts Warm front: when a warm air mass pushes into and over a cold air mass. Cold front: when a cold air mass pushes into and under a warm air mass. ▫Bring brief downpours, gusty winds, and cool temps.

28. Large-Scale Weather Systems: Weather Forecasting Weather forecasting: an attempt to make accurate predictions of future weather. Short-range local forecasts are easy. ▫Based on air pressure readings, cloud observations, and wind direction ▫Usually good for a two-day time span Weather forecasters use information from weather satellites and radar to improve predictions. Weather systems usually move from west to east across the U.S. (because of the Westerlies).

29. Large-Scale Weather Systems: Weather Forecasting Long-range weather is harder because weather conditions can change or fronts can move.

30. Interaction of Humans and the Atmosphere: Weather Hazards Weather directly affects our lives. For example, floods. ▫Destroy property ▫Close schools ▫Ruin crops ▫Make travel dangerous ▫Injuries and deaths

31. Interaction of Humans and the Atmosphere: Storms Storms: natural disturbances in the atmosphere that involve low air pressure, clouds, precipitation, and strong winds. The major types: ▫Thunderstorms ▫Hurricanes ▫Tornadoes ▫Winter storms

32. Interaction of Humans and the Atmosphere: Thunderstorms Thunderstorms: brief, intense storms that affect a small area. Produced when rapid rising warm air causes cumulus cloud to build up. Characterized by lightening, thunder, strong winds, and sometimes hail. Stay indoors and avoid hilltops, open fields, beaches, and bodies of water because these are likely to be struck by lightening.

33. Interaction of Humans and the Atmosphere: Hurricanes Hurricanes: a huge rotating storm that forms over the ocean near the equator. ▫Produce strong winds, heavy rains, and large, powerful waves. ▫The calm in the middle is called the eye. Can cause severe flooding and damage. For safety, seek higher ground.

34. Interaction of Humans and the Atmosphere: Tornadoes Tornadoes: violently whirling winds, sometimes visible as a funnel-shaped cloud. Produced by severe thunderstorms. ▫High-speed winds and low air pressure They usually appear quickly and disappear just as quick. Have great strength and destroy most things in their path. Safest place is underground.

35. Interaction of Humans and the Atmosphere: Winter Storms Winter storms: cold storms that include blizzards and ice storms. Blizzards are storms with strong winds that blow snow with cold temperatures. Ice storms occur when rain freezes and coats everything in ice. To stay safe, remain indoors.

36. Interaction of Humans and the Atmosphere: Pollution Factories, cars, power plants, and airplanes produce harmful substances called pollutants. ▫A buildup of pollutants can cause weather problems. Smog: a haze formed by the reaction of sunlight with chemicals in automobile exhaust and factory smoke.

37. Interaction of Humans and the Atmosphere: Pollution Acid rain: occurs when the acidity of the moisture in clouds increases, it can harm lakes, forests, and organisms. ▫Can fall far from the source of the pollutants since prevailing winds can carry pollutants Many industries produce carbon dioxide. Carbon dioxide traps heat close to the Earth. Many scientists fear that the buildup of too much carbon dioxide can lead to global warming, called the greenhouse effect.

38. Interaction of Humans and the Atmosphere: Pollution

39. Natural events can also release pollutants. ▫Forest fires, volcanoes, etc. There is little we can do about natural pollutants, but we can control our own activities to avoid continuous harmful activity to the planet.

40. The Hydrosphere: Oceans of Earth The five oceans cover three-fourths of the Earth. ▫Pacific, Atlantic, Indian, Arctic, and Antarctic ▫The Pacific Ocean covers more area than all the land combined.

41. The Hydrosphere: Motions of Ocean Water The oceans are always in motion and the exchange of energy with the atmosphere plays a role in these motions.

42. The Hydrosphere: Wind and Waves Winds produces waves by causing friction at the water’s surface. Tides: the daily rise and fall of ocean waters. ▫The energy for tides comes from the gravitational pull of the moon, and somewhat from the sun. ▫Each day there are two high tides, and two low tides.

43. The Hydrosphere: Wind and Waves Surface currents: produced by global winds blowing great distances across the ocean’s surface. Density currents: movements of water caused by differences in its density ▫Cold water is denser than warm water ▫Salt water is denser than fresh water ▫Sediment-filled water is heavier than clear water Tsunami waves: violent waves produced by earthquakes, volcanoes, and landslides.

44. Questions? Chapter 7: Atmosphere, Hydrosphere, and Lithosphere