Climate: Understanding Weather Patterns and Climate Zones

1. Chapter 17 Climate Preview Section 1 What Is Climate? Section 2 The Tropics Section 3 Temperate and Polar Zones Section 4 Changes in Climate Concept Mapping

2. Section1 What Is Climate? Chapter 17 Bellringer • Pretend you are entering a contest for a free trip to a place with perfect climate. To win, write a description of your idea of the perfect climate in 25 words or less. Do you know of any real place where your dream climate really exists? • Record your response in your science journal.

3. Section1 What Is Climate? Chapter 17 Objectives • Explain the difference between weather and climate. • Identify five factors that determine climates. • Identify the three climate zones of the world.

4. Section1 What Is Climate? Chapter 17 Climate Vs. Weather • Weather is the condition of the atmosphere at a particular time. • Climate is the average weather condition in an area over a long period of time.

5. Section1 What Is Climate? Chapter 17 Latitude • Solar Energy and Latitude The amount of direct solar energy a particular area receives is determined by latitude. Latitudeis the distance north or south, measured in degrees, from the equator.

6. Section1 What Is Climate? Chapter 17 Latitude, continued • Seasons and LatitudeSeasons happen because the Earth is tilted on its axis at a 23.5° angle. This tilt affects how much solar energy an area receives as Earth moves around the sun.

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8. Section1 What Is Climate? Chapter 17 Prevailing Winds • Winds that blow mainly from one direction are prevailing winds. • Prevailing winds affect the amount of precipitation that a regions receives. • The circulation of warm and cold air cause prevailing winds.

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10. Section1 What Is Climate? Chapter 17 Mountains • Mountains can influence an area’s climate by affecting both temperature and precipitation. • Elevation is the height of surface landforms above sea level. • As the elevation increases, the ability of air to transfer energy from the ground to the atmosphere decreases.

11. Section1 What Is Climate? Chapter 17 Large Bodies of Water • Large bodies of water can influence an area’s climate. Water absorbs and releases heat slower than land does. Because of this quality, water helps to moderate the temperatures of the land around it. Ocean Currents • As surface currents move, they carry warm or cool water to different locations. The surface temperature of the water affects the temperature of the air above it.

12. Section1 What Is Climate? Chapter 17 Surface Currents and Climates Click below to watch the Visual Concept. Visual Concept

13. Section1 What Is Climate? Chapter 17 Climates of the World • The Earth’s three major climate zones are determined by latitude. • Climates zones are made up of different biomes. Biomes are characterized by certain types of plant and animal communities.

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15. Section2 The Tropics Chapter 17 Bellringer • Imagine you are a zoologist hired to design a camel and a deer exhibit for your community's new zoo. Describe the differences between a deer and a camel. Where and in what kind of climate are you most likely to find these animals? What would you have to provide for each of these animals so they would continue to flourish? • Write your exhibit proposal in your science journal.

16. Section2 The Tropics Chapter 17 Objectives • Locateand describe the tropical zone. • Describe the biomes found in the tropical zone.

17. Section2 The Tropics Chapter 17 The Tropical Zone • The region that surrounds the equator and that extends from about 23.5˚ north latitude to 23.5˚ south latitude is calledtropical zone.

18. Section2 The Tropics Chapter 17 The Tropical Zone, continued • Tropical Rain Forests Tropical rain forests are always warm and wet. Because they are located near the equator, they receive strong sunlight year-round. • Tropical rain forests contain the greatest number of animal and plant species of any biome.

19. Section2 The Tropics Chapter 17 The Tropical Zone, continued • Tropical SavannasTropical savannas, or grasslands, are composed of tall grasses and a few scattered trees. The climate is usually very warm. • Tropical savannas have a dry season that lasts four to eight months and that is followed by short periods of rain.

20. Section2 The Tropics Chapter 17 The Tropical Zone, continued • Tropical Deserts A desert is an area that receives less that 25 cm of rainfall per year. • Daily temperatures in tropical deserts often vary from very hot daytime temperatures to cool nighttime temperatures.

21. Section3 Temperate and Polar Zones Chapter 17 Bellringer • You have been selected to join an expedition to the North Pole. What kinds of gear will you need? How will you travel both to the Pole and once you arrive in the Arctic? What will you bring to eat? Will you be able to hunt? Write a description in your science journal of what activities you might engage in during an average week of your expedition.

22. Section3 Temperate and Polar Zones Chapter 17 Objectives • Locate and describe the temperate zone and the polar zone. • Describe the different biomes found in the temperate zone and the polar zone. • Explain what a microclimate is.

23. Section3 Temperate and Polar Zones Chapter 17 The Temperate Zone • The climate zone between the Tropics and the polar zone is the temperate zone. Latitudes in the temperate zone receive less solar energy than latitudes in the Tropics do.

24. Section3 Temperate and Polar Zones Chapter 17 The Temperate Zone, continued • Temperate ForestsThe temperate forest biomes tend to have high amounts of rainfall and seasonal temperature differences. • Both deciduous trees and evergreen trees grow in temperate forests.

25. Section3 Temperate and Polar Zones Chapter 17 The Temperate Zone, continued • Temperate Grasslands Temperate grasslands are regions that receive too little rainfall for trees to grow. This biome has warm summers and cold winters. • Grasses are the most common kind of plant found in this biome.

26. Section3 Temperate and Polar Zones Chapter 17 The Temperate Zone, continued • ChaparralsChaparral regions have cool, wet winters and hot, dry summers. The vegetation is mainly evergreen shrubs. • These shrubs are short, woody plants with thick waxy leaves. The waxy leaves are adaptations that help prevent water loss in dry conditions.

27. Section3 Temperate and Polar Zones Chapter 17 The Temperate Zone, continued • Temperate Deserts The temperate desert biomes tend to be cold deserts. Like all deserts, cold deserts receive less than 25 cm of precipitation yearly. • Temperate deserts can be very hot in the daytime. But, unlike hot deserts, they are often very cold at night.

28. Section3 Temperate and Polar Zones Chapter 17 The Polar Zone • The climate zone located at the North or South Pole and its surrounding area is called the polar zone. Polar climates have the coldest average temperatures of all the climate zones.

29. Section3 Temperate and Polar Zones Chapter 17 The Polar Zone, continued • TundraThe tundra biome has long, cold winters with almost 24 hours of night. It also has short, cool summers with almost 24 hours of daylight. • In the summer, only the top meter of soil thaws. Underneath the thawed soil lies a permanently frozen layer of soil, called permafrost.

30. Section3 Temperate and Polar Zones Chapter 17 The Polar Zone, continued • Taiga (Northern Coniferous Forest)The taiga has long, cold winters and short, warm summers. • The majority of the trees are evergreen needle-leaved trees called conifers. The needles and flexible branches allow these trees to shed heavy snow before they can be damaged.

31. Section3 Temperate and Polar Zones Chapter 17 Microclimates • The climate and the biome of a particular place can also be influenced by local conditions. Microclimate is a climate of a small area. • Citiesare also microclimates. In a city, temperatures can be 1°C to 2°C warmer than the surrounding rural areas.

32. Section4 Changes in Climate Chapter 17 Bellringer • Imagine that the climate in the area where you live has changed so that it is now warmer than it used to be. Write down five ways how you think warmer temperatures would affect the area. • Write your answers in your science journal.

33. Section4 Changes in Climate Chapter 17 Objectives • Describehow the Earth’s climate has changed over time. • Summarize four different theories that attempt to explain why the Earth’s climate has changed. • Explainthe greenhouse effect and its role in global warming.

34. Section4 Changes in Climate Chapter 17 Ice Ages • An ice age is a period during which ice collects in high latitudes and moves toward lower latitudes. • During glacial periods, enormous sheets of ice advance to cover a larger portion of the Earth.

35. Section4 Changes in Climate Chapter 17 Ice Ages, continued • Interglacial Periods Warmer times that happen between glacial periods are called interglacial periods. During an interglacial period, the ice begins to melt and the sea level rises again. • Motions of the Earth There are many theories about the causes of ice ages. The Milankovitch theory explains why an ice age alternates between cold and warm periods.

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37. Section4 Changes in Climate Chapter 17 Ice Ages, continued • Ice Ages The Earth’s climate is further influenced by plate tectonics and continental drift. One theory proposes that ice ages happen when the continents are positioned closer to the polar regions.

38. Section4 Changes in Climate Chapter 17 Volcanic Eruptions • Many natural factors can affect global climate. Catastrophic events, such as volcanic eruptions, can influence climate.

39. Section4 Changes in Climate Chapter 17 Effects of Volcanoes on Earth Click below to watch the Visual Concept. Visual Concept

40. Section4 Changes in Climate Chapter 17 Asteroid Impact • Dramatic Climatic Change Scientists believe that if an asteroid this big hit the Earth, it could change the climate of the entire world.

41. Section4 Changes in Climate Chapter 17 The Sun’s Cycle • Some changes in the climate can be linked to changes in the sun. • The sun follows an 11-year cycle. During this cycle, the sun changes from a solar maximum to a solar minimum. • When the sun is at its solar maximum, it produces a large percentage of high-energy radiation. This increase in radiation warms the winds in the atmosphere.

42. Section4 Changes in Climate Chapter 17 Global Warming • A gradual increase in the average global temperature is calledglobal warming. • The Earth’s natural heating process, in which gases in the atmosphere trap thermal energy, is called the greenhouse effect. • Many scientists think that if the global temperature continues to rise, the ice caps will melt and cause flooding.

43. Climate Chapter 17 Concept Mapping Use the terms below to complete the concept map on the next slide.

44. Climate Chapter 17

45. Climate Chapter 17