NEW CHAPTER the BIG idea Some features of weather have predictable patterns. Weather Patterns Air pressure varies in the atmosphere. The atmosphere has wind patterns. Most clouds form as air rises and cools. Water falls to Earth’s surface as precipitation. CHAPTER CHAPTER OUTLINE CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME barometer air pressure Air pressure varies in the atmosphere. SECTION OUTLINE SECTION OUTLINE 3.1 CHAPTER RESOURCES CHAPTER RESOURCES CALIFORNIA Content Standards 6.4.e Students know differences in pressure, heat, air movement, and humidity result in changes of weather.

VOCABULARY KEY CONCEPT CHAPTER HOME Air pressure is the force of air molecules pushing on an area. Air pressure decreases as you move higher in the atmosphere. Air pressure can also differ in two locations at the same altitude. barometer air pressure Air pressure varies in the atmosphere. SECTION OUTLINE SECTION OUTLINE 3.1 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME The force of air molecules pushing on an area. air pressure KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY barometer air pressure Air pressure varies in the atmosphere. 3.1 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME An instrument that measures air pressure in the atmosphere. barometer KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY barometer air pressure Air pressure varies in the atmosphere. 3.1 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME wind global wind Coriolis effect The atmosphere has wind patterns. SECTION OUTLINE SECTION OUTLINE jet stream monsoon 3.2 CHAPTER RESOURCES CHAPTER RESOURCES CALIFORNIA Content Standards 6.4.a Students know the sun is the major source of energy for phenomena on Earth’s surface; it powers winds, ocean currents, and the water cycle. 6.4.e Students know differences in pressure, heat, air movement, and humidity result in changes of weather. weather

VOCABULARY KEY CONCEPT CHAPTER HOME Wind blows from areas of high pressure toward areas of low pressure. Earth's rotation causes long distance winds to curve. wind global wind Coriolis effect The atmosphere has wind patterns. SECTION OUTLINE SECTION OUTLINE jet stream monsoon area of high pressure area of low pressure 3.2 VISUALIZATION View an animation of the Coriolis effect. CLASSZONE.COM VISUALIZATION Explore how breezes blowing over land and water change over the course of a day. CLASSZONE.COM CHAPTER RESOURCES CHAPTER RESOURCES weather

VOCABULARY KEY CONCEPT CHAPTER HOME The condition of Earth’s atmosphere at a particular time and place. weather KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY wind global wind Coriolis effect monsoon The atmosphere has wind patterns. 3.2 CHAPTER RESOURCES CHAPTER RESOURCES jet stream weather

VOCABULARY KEY CONCEPT CHAPTER HOME The horizontal movement of air caused by differences in air pressure. wind KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY wind global wind Coriolis effect monsoon The atmosphere has wind patterns. 3.2 CHAPTER RESOURCES CHAPTER RESOURCES jet stream weather

VOCABULARY KEY CONCEPT CHAPTER HOME Winds that travel long distances in steady patterns over several weeks. global wind KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY wind global wind Coriolis effect monsoon The atmosphere has wind patterns. 3.2 CHAPTER RESOURCES CHAPTER RESOURCES jet stream weather

VOCABULARY KEY CONCEPT CHAPTER HOME The influence of Earth’s rotation on objects that move over Earth. Coriolis effect KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY wind global wind Coriolis effect monsoon The atmosphere has wind patterns. 3.2 CHAPTER RESOURCES CHAPTER RESOURCES jet stream weather

VOCABULARY KEY CONCEPT CHAPTER HOME A wind that flows in the upper troposphere from west to east over vast distances at great speeds. jet stream KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY wind global wind Coriolis effect jet stream monsoon The atmosphere has wind patterns. 3.2 CHAPTER RESOURCES CHAPTER RESOURCES weather

VOCABULARY KEY CONCEPT CHAPTER HOME A wind that changes direction with the seasons. monsoon KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY wind global wind Coriolis effect monsoon The atmosphere has wind patterns. 3.2 CHAPTER RESOURCES CHAPTER RESOURCES jet stream weather

VOCABULARY KEY CONCEPT CHAPTER HOME Most clouds form as air rises and cools. SECTION OUTLINE SECTION OUTLINE precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES CALIFORNIA Content Standards 6.4.a Students know the sun is the major source of energy for phenomena on Earth’s surface; it powers winds, ocean currents, and the water cycle. 6.4.e Students know differences in pressure, heat, air movement, and humidity result in changes of weather.

VOCABULARY KEY CONCEPT CHAPTER HOME Clouds are made of tiny water droplets or ice crystals that condense from water vapor in rising air. Most clouds form as air rises and cools. SECTION OUTLINE SECTION OUTLINE precipitation humidity saturation evaporation relative humidity dew point condensation level where condensation begins 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME The process by which a gas changes into a liquid. evaporation KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME The process by which a gas changes into a liquid. condensation KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME Any type of liquid or solid water that falls to Earth’s surface, such as rain, snow, or hail. precipitation KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME The amount of water vapor in air. humidity KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME A condition of the atmosphere in which the rates of evaporation and condensation are equal. saturation KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME The comparison of the amount of water vapor in air with the maximum amount of water vapor that can be present in air at that temperature. relative humidity KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME The temperature at which air reaches saturation. dew point KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME Water falls to Earth’s surface as precipitation. SECTION OUTLINE SECTION OUTLINE sleet hail acid rain freezing rain 3.4 CHAPTER RESOURCES CHAPTER RESOURCES CALIFORNIA Content Standards 6.4.a Students know the sun is the major source of energy for phenomena on Earth’s surface; it powers winds, ocean currents, and the water cycle. 6.4.e Students know differences in pressure, heat, air movement, and humidity result in changes of weather.

VOCABULARY KEY CONCEPT CHAPTER HOME Water falls to Earth’s surface as precipitation. SECTION OUTLINE SECTION OUTLINE sleet hail acid rain freezing rain Water droplets in clouds merge to form raindrops. Ice crystals in clouds can form snow, rain, and other types of precipitation. Hail forms when ice pellets move up and down in clouds, growing larger as they gain layers of ice. Snow forms from ice crystals that merge in clouds. Sleet is rain that freezes into ice pellets while falling through cold air. Freezing rain is rain that freezes when it hits the ground or other surfaces. 3.4 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME Rain that freezes when it hits the ground or another surface and coats the surface with ice. freezing rain KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY sleet hail acid rain freezing rain Water falls to Earth’s surface as precipitation. 3.4 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME Small pellets of ice that form when rain passes through a layer of cold air and freezes before hitting the ground. sleet KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY sleet hail acid rain freezing rain Water falls to Earth’s surface as precipitation. 3.4 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME Layered lumps or balls of ice that fall from cumulonimbus clouds. hail KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY sleet hail acid rain freezing rain Water falls to Earth’s surface as precipitation. 3.4 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME Rain that has become more acidic than normal due to pollution. acid rain KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY sleet hail acid rain freezing rain Water falls to Earth’s surface as precipitation. 3.4 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME I. Air pressure varies in the atmosphere. A. Air exerts pressure. B. Air pressure is related to altitude and density. 1. Pressure and Air Motion 2. Barometers and Air Pressure KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Air pressure varies in the atmosphere. barometer air pressure 3.1 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME II. The atmosphere has wind patterns. A. Uneven heating causes air to move. B. Earth’s rotation affects wind direction. C. Bands of calm air separate global wind belts. D. Jet streams flow near the top of the troposphere. KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY The atmosphere has wind patterns. E. Patterns of heating and cooling cause local winds and monsoons. 1. Calm Regions 2. Wind Belts 3. Effects of Wind on Travel 1. Local Winds 2. Monsoons wind global wind Coriolis effect monsoon 3.2 CHAPTER RESOURCES CHAPTER RESOURCES jet stream weather

VOCABULARY KEY CONCEPT CHAPTER HOME III. Most clouds form as air rises and cools. A. Temperature affects water in the air. 1. Water in the Air 2. Humidity and Relative Humidity B. Water vapor condenses and forms clouds. 1. Characteristics of Clouds 2. Cirrus Clouds KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Most clouds form as air rises and cools. 3. Cumulus Clouds 4. Stratus Clouds 5. Fog precipitation humidity saturation evaporation relative humidity dew point condensation 3.3 CHAPTER RESOURCES CHAPTER RESOURCES

VOCABULARY KEY CONCEPT CHAPTER HOME IV. Water falls to Earth’s surface as precipitation. A. Precipitation forms from water droplets or ice crystals. 1. Measuring Precipitation 2. Types of Precipitation B. Precipitation can carry pollution. KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Water falls to Earth’s surface as precipitation. sleet hail acid rain freezing rain 3.4 CHAPTER RESOURCES CHAPTER RESOURCES

CHAPTER HOME Image Gallery Click on the icons to see a larger image or animation. VISUALIZATION View an animation of the Coriolis effect. CLASSZONE.COM VISUALIZATION Explore how breezes blowing over land and water change over the course of a day. CLASSZONE.COM

CHAPTER HOME Image Gallery BACK TO IMAGE GALLERY

CHAPTER HOME Image Gallery BACK TO IMAGE GALLERY

CHAPTER HOME Image Gallery BACK TO IMAGE GALLERY

CHAPTER HOME Image Gallery BACK TO IMAGE GALLERY

CHAPTER HOME Image Gallery BACK TO IMAGE GALLERY

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