1. Weather and Climate Preview Section 1: Factors Affecting Climate
World Geography Today
11/13/2018
Weather and Climate
Preview
Section 1: Factors Affecting Climate
Section 2: Weather Factors
Section 3: Climate and Vegetation Patterns
Chapter Wrap-Up
Chapter 3

2. Section 1: Factors Affecting Climate
World Geography Today
11/13/2018
Section 1: Factors Affecting Climate
Read to Discover
How does the Sun affect Earth’s atmosphere?
How does atmospheric pressure distribute energy around the globe?
How do global wind belts affect weather and climate?
How do the oceans affect weather and climate?
Chapter 3

3. Section 1: Factors Affecting Climate
Question
By which processes does the Sun interact with Earth’s atmosphere?

4. Section 1: Factors Affecting Climate
The Sun’s Effect on Earth
The other half is absorbed by Earth’s surface and converted into heat energy.
The greenhouse effect helps keep the planet warm.
The Sun’s energy reaches Earth.
Half of the energy is reflected back into space or absorbed by the atmosphere.
The atmosphere traps this heat in a process called the greenhouse effect.

5. Section 1: Factors Affecting Climate
Atmospheric Pressure
Low-pressure zones are caused by warm air, which expands and rises.
High-pressure zones are caused by cold air, which is dense and sinks.
Pressure differences cause airflow and energy distribution around the globe.
Warm air moves through the upper atmosphere until the air cools and falls; cold air sinks toward Earth’s surface and then heats up and rises.

6. Section 1: Factors Affecting Climate
Global Winds
Pressure differences cause wind.
Winds move heat and cold across Earth’s surface.
Prevailing winds blow from the same direction most of the time, causing similar weather.
A front occurs when two air masses of widely different temperatures or moisture levels meet.

7. Section 1: Factors Affecting Climate
Oceans
Water heats and cools more slowly than land, making coastal areas milder than inland areas.
Ocean currents move heat between the tropics and polar regions, helping to maintain Earth’s energy balance.

8. Section 2: Weather Factors
Read to Discover
What are the common forms of precipitation, and how are they formed?
How do mountains and elevation affect weather and climate?
What are the different types of storms, and how do they form?

9. Section 2: Weather Factors
Question
What are the steps in the formation of precipitation, and what are the four common types of precipitation?

10. Section 2: Weather Factors
Formation of Precipitation
Condensation clouds, dew, fog, frost
Evaporation
Humidity
Rain
Snow
Sleet
Hail

11. Section 2: Weather Factors
Forms of Precipitation
Rain—Liquid formed through condensation of water vapor
Snow—Ice crystals formed in clouds
Sleet—Rain that freezes as it falls
Hail—Chunks of ice formed in storm clouds

12. Section 2: Weather Factors
Question
How do mountains and elevation affect weather and climate?

13. Section 2: Weather Factors
Increase in elevation causes drop in temperature.
Mountains cause orographic effect: Moist air meets a barrier and is pushed upward, causing cooling, condensation, and precipitation.
Mountainside facing wind is the windward, wetter side; side facing away from wind is the leeward, drier side, called the rain shadow.

14. Section 2: Weather Factors
Types of Storms
Middle-latitude storms form when cold, dry polar air mixes with moist, warm tropical air. Examples include thunderstorms and tornadoes.
Tropical storms are usually smaller and lack fronts. Examples include hurricanes and typhoons.

15. Section 3: Climate and Vegetation Patterns
World Geography Today
11/13/2018
Section 3: Climate and Vegetation Patterns
Read to Discover
How do the two tropical climates differ?
What conditions are common in dry climates?
What climates are found in the middle latitudes?
What characterizes high-latitude and highland climates?
Chapter 3

16. Section 3: Climate and Vegetation Patterns
Question
What are the characteristics of tropical humid and tropical wet and dry climates?

17. Section 3: Climate and Vegetation Patterns
Tropical Humid Climate
Tropical Wet and Dry Climates
Close to equator
Warm temperatures
Rainfall all year
Receives Sun’s rays directly all year
Rising warm air
Rain forests
Monsoons
North and south of tropical humid
Caused by seasonal change in this area
Alternating wet and dry seasons
Savannas

18. Section 3: Climate and Vegetation Patterns
Dry Climate Areas
Generally centered about 30 degrees north and south of equator
Subtropical high-pressure zone causes sinking dry air, with little rain.
Winters may be very cold, summers very hot.
Hardy plants and animals

19. Section 3: Climate and Vegetation Patterns
Middle-Latitude Climates
Mediterranean—Long, dry summers and mild winters; scrub woodland vegetation
Humid Subtropical—Hot, humid summers and mild winters; temperate forests
Marine West Coast—Mild all year; may support dense forests
Humid Continental—Variable, with four seasons; enough rain to support forests

20. Section 3: Climate and Vegetation Patterns
High-Latitude and Highland Climates
Subarctic—Long, cold winters and short, warm summers; vast evergreen forests
Tundra—Long winters, with permafrost; low shrubs, lichens, mosses, ferns
Ice Cap—Polar climates; few land plants or animals
Highland—Varies by elevation, with low elevations relatively mild and high elevations similar to ice cap

21. Chapter Wrap-Up Understanding the Main Ideas
World Geography Today
11/13/2018
Chapter Wrap-Up Understanding the Main Ideas
How does latitude relate to climate?
How do atmospheric pressure zones and ocean currents affect Earth’s energy balance?
On a global scale, where is precipitation most common?
What effects can hurricanes have on local environments?
Where will you find climates that are generally warm and wet all year? What creates dry weather conditions in arid regions?
Chapter 3