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pp. 48- 77

Chapter 3: Climate, Environment, and

Resources

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WeatherThe short-term

changes in the air for a given place and time.

Temperature and precipitation from hour to hour or day to day

A region’s average weather conditions over a long period

The expected weather for a place based on data and experience

Ch. 3 Section 1: Weather and Climate

Climate

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Weight of air Cold air is heavier than warm air. When air cools, it gets heavier and sinks. When air warms, it gets lighter and rises. As warm air rises, cooler air moves in to take its place,

creating wind. The rising, sinking, and flowing of air creates Earth’s

prevailing wind patterns. At the equator, hot air rises and flows toward the poles. At the poles, cold air sinks and flows toward the equator. Earth’s rotation causes prevailing winds to curve east or

west. Prevailing winds are winds that blow in the same

direction over large areas of Earth. Prevailing winds can make a region warmer or colder and drier or wetter.

Ch. 3 Section 1: Weather and Climate

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Ocean currents—large streams of surface seawater driven by winds—move heat around Earth. Carry warm or cool water to different areas Water’s temperature affects air temperature near it.

Large bodies of water, such as an ocean or sea, also affect climate. Water heats and cools more slowly than land does. Large bodies of water make the temperature of the land

nearby milder. The place where two air masses of different temperatures

or moisture content meet is a front. Can produce rain, snow, thunderstorms, and

blizzards.

Ch. 3 Section 1: Weather and Climate

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Thunderstorms• Produce rain, lightning,

and thunder

• Most common in spring and summer

• Small, rapidly twisting funnel of air that touches the ground

• Can be destructive and deadly

Ch. 3 Section 1: Weather and Climate

Tornadoes

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Blizzards• Produce strong winds

and large amounts of snow

• Most common during winter

• Large, rotating storms that form over tropical waters in the Atlantic Ocean (hurricanes) or Pacific Ocean (typhoons).

• Produce drenching rains, strong winds, and storm surges

• Largest, most destructive storms

Ch. 3 Section 1: Weather and Climate

Hurricanes and Typhoons

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Mountains can influence an area’s climate by affecting both temperature and precipitation.

Temperature decreases with elevation, the height on Earth’s surface above sea level.

Mountains also create wet and dry areas.Air blowing against mountains is forced to rise.As the air rises, it cools and precipitation falls.This effect produces a rain shadow, a dry area

on the mountainside facing away from the direction of the wind.

Ch. 3 Section 1: Weather and Climate

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Earth is divided into five general climate zones.Tropical—occur near the equator, in low

latitudesTemperate—occur about halfway between the

equator and the poles, in the middle latitudesPolar—occur near the poles, in the high

latitudesDry—occurs at many different latitudesHighland—occurs at many different latitudes

Geographers divide some climate zones into more specific climate regions.

Ch. 3 Section 2: World Climates

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Humid Tropical Region At the equatorWarm, muggy and rainy

year-roundTemperatures average 80F.Rainfall ranges from 70 to

450 inches.Some areas have

monsoons, seasonal winds that bring either dry or moist air.

Can support lush tropical rain forests that host a great diversity of plant and animal life

North and south away from the equator

Long, hot, dry season followed by short periods of rain

Temperatures are hot in the summer, cooler in the winter.

Can support savannas—areas of tall grasses and scattered trees and shrubs

Tropical climate zones are wet and warm

Tropical Savanna Region

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Desert Climate RegionEarth’s hottest and driest

climateReceive less than 10

inches of rain a yearTemperatures can reach as

high as 130F.Only very hardy plants and

animals can live in these conditions.

Semidry grasslands or prairies—called steppes

Often border desertsReceive slightly more

rain than desertsShort grasses are most

common plants, but shrubs and trees grow along streams and rivers.

Dry climate zones receive little or no rain

Steppe Climate Region

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Temperate ClimatesMild and tend to have four seasons

Warm or hot summersCool or cold winters

Occur in the middle latitudes, the regions halfway between the equator and the poles

Temperate Climate Zones

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Mediterranean Climate Region• Sunny, pleasant

climate occurring mainly in coastal areas

• Summers hot, dry, and sunny; winters mild and somewhat wet

• Occurs along east coasts near the tropics

• Summers are hot and muggy; winters are mild

• Storms occur year-round.

Temperate Climate ZonesHumid Subtropical Climate Region

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Marine West Coast Climate Region• Occurs on west

coasts where winds carry moisture in from the seas

• Mild temperatures year-round

• Occurs closer to the poles, in the upper-middle latitudes

• Four distinct seasons

Temperate Climate ZonesHumid Continental Climate Region

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Subarctic Climate RegionOccurs mainly in

Northern hemisphere south of Arctic Ocean

Winters are long and bitterly cold; summers short and cool

Below freezing half the year

Coastal areas along the Arctic Ocean

Long, bitterly cold winters

In some parts is permafrost, or permanently frozen layers of soil

Polar climate zones are cold and dryTundra Climate Region

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Ice Cap Climate Region• North and South poles• Temperature lows of more than -120F• Snow and ice remain year-round, but little

precipitation

Polar climate zones are cold and dry

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• Found on mountains• Includes polar climates plus others; several climates in one

• As you go up a mountain, temperatures drop and plant life grows sparser.

Highland Climate Zone

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Plants and animals live where they are suited to the environment, or surroundings.Factors such as temperature, rainfall, and soil

conditions limit options of where they can live.All plants and animals are adapted to specific

environments.Ecosystem—a group of plants and animals that

depend on each other for survival and the environment in which they liveFormed from interconnections between living

things and the environmentCan be any size and can occur wherever

air, water, and soil support life

Ch. 3 Section 3: Natural Environments

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Soils help determine what plants will grow and how well.

Fertile soils are rich in minerals and humus, decayed plant or animal matter.Support abundant life

Soils can lose fertility in many ways.ErosionPlanting the same crops over and over

When soil becomes worn out, it cannot support as many plants.Can lead to desertification, the spread of

desert-like conditions

Ch 3 Section 3: Natural Environments

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• A natural resource is any material in nature that people use and value.

• Some are used as is.• Some are changed to make something new.

Ch. 3 Section 4: Natural Resources

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Types of Natural Resources• Renewable resources are resources Earth replaces naturally.

• Nonrenewable resources are resources that cannot be replaced; they will run out one day.

• People must manage resources to ensure they will be available in the future.

• Deforestation, the clearing of trees, is a result of lack of management.

• Reforestation, planting trees to replace lost forestland, works to prevent resource loss.

Ch. 3 Section 4: Natural Resources

Managing Natural Resources

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Nonrenewable ResourcesMost energy we use comes

from fossil fuels, nonrenewable resources that formed from the remains of ancient plants and animals.

Coal—pollutes the air; used mainly to create electricity at power plants

Petroleum, or oil—used to make fuels and other products

Natural gas—cleanest-burning fossil fuel; used mainly for heating and cooking

Will not run outGenerally better for the

environmentHydroelectric power—the

production of electricity from waterpower—is the main alternative to fossil fuels.

Wind is used to power wind turbines that create electricity.

Solar power and geothermal energy—heat from within Earth—can heat water for homes and be turned into electricity.

Ch. 3 Section 4: Natural Resources

Renewable Resources

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Nuclear EnergyObtained by splitting atoms, small

particles of matterUses the metal uranium, so some consider

it a nonrenewable resourceProduces dangerous wastes that must be

stored for thousands of years before they are safe

Accidents at nuclear power plants have terrible effects.

Ch. 3 Section 4: Natural Resources

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Mineral resources include metals, salt, rocks, and gemstones.

Minerals are nonrenewable, and therefore need to be conserved.

Recycling can make the supply of mineral resources last longer.

Ch. 3 Section 4: Natural Resources

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The natural resources available to people affect their lifestyles and needs. People in areas with many natural resources sometimes

have more choices on ways to dress, eat, live, travel, and entertain themselves.

People in areas with fewer natural resources will likely have fewer choices and different needs.

Availability of natural resources affects countries’ economies. The many resources available in the United States have

helped it become one of the world’s wealthiest economies.

Countries with few natural resources often have weak economies.

Some countries have only one or two valuable resources but few others.

Ch. 3 Section 4: Natural Resources