Chapter2:PhysicalGeography

Pg.39-68

LearningGoalsforChp 2:q ExplainhowtheEarthmovesinspaceandwhyseasonschange.q Outlinethefactorsthatinfluenceclimateandrecognizedifferentclimate

zones.q UnderstandhowforcesinsidetheEarthandonitssurfaceaffectthe

shapeoftheland.q Identifydifferentlandforms&waterways.q Describethewatercycleandhowitsavailabilityaffectslifeinvarious

regions.

Chapter 2, Lesson 1Planet Earth

4.6 billion years old and still changing!

Pg. 42-51

The Solar System –The Sun, 8 planets, moons & satellites

• Earth-like planets – Earth, Mercury, Venus, Mars, (Pluto?)• Small, rocky, few moons,

rotate slowly• Jupiter-like planets –

Jupiter, Saturn, Neptune, Uranus• Large balls of gas, many

moons, rotate quickly, have rings

Earthʼs Layers

• Core – inner is solid, outer is molten rock• Mantle – made of magma (melted rock)• Crust – 31-62 miles thick

4 Parts of the Earth’s Physical Geography

• Atmosphere – 100-mile thick layer of air (Mostly nitrogen & oxygen) around the earth that allows life to exist • Lithosphere - land• Hydrosphere – water • Biosphere - living things

Earthʼs Movement

• 1 day: 1 complete rotation on its axis• 1 year: 365 ¼ days of revolution around the sun• Leap year: every 4 years, 1 extra day is added to the year (Feb. 29) to

make up for the ¼ day

Earth’s Revolution & the 4 Seasons(Northern Hemisphere)

Weather & Climate:What’s the difference?• Weather –• short period of time – temperature, precipitation, & wind• Constantly changing

• Climate –• Typical weather over a long period of time• May change very slowly over a long time

What causes climate?• The Sun’s rays & latitude• Warmer near the Equator

• Wind (map pg. 47)• Prevailing winds & doldrums (“horse latitudes”)

• Ocean currents

What causes climate?

• Landforms• Mountains – can cause rain shadows by blocking precipitation

• Nearby bodies of water• Continental climate – inland climate with temperature extremes, between mild

and polar• Elevation

World Climate Zones

• Based mostly on temperature and precipitation• Have plants and animals unique to those regions• Tropical, Desert, Humid Temperate, Cold Temperate,

Polar, & High Mountain

Tropical Climate Zones

• Tropical Rain Forest - wet• Tropical Savanna – 2 seasons (wet & dry)

Desert

• Hot or cold

Humid TemperateClimate Zones• Experience 4 seasons with

a range of temp & precipitation

ColdTemperateClimateZones

• Shortsummersandcoldwinters

PolarClimate Zones

• Very cold and often year-round snow cover

High Mountain Climate Zones

• Temps change rapidly as altitude increases, but usually cool to cold

How Humans affect Climate

• Global Warming • Burning fuel causes high levels of certain gases in the atmosphere• These gases trap more solar radiation from escaping, warming the earth

• Clearing of rain forests for lumber and farmland• Burning trees causes air pollution• Less evaporation from trees à less rain

Chapter 2, Lesson 2A Changing Earth

Pg. 52-57

Forces that change Earth’s landforms

• Plate tectonics – theory that the earth’s crust is made of moving plates floating on liquid rock • Pangaea à

When Tectonic Plates Meet

• High mountains – 2 continental plates collide• Volcanoes & islands• Earthquakes along fault lines• Tsunamis – huge waves caused by undersea earthquakes

Weathering

• The breakdown of rock at or near the earthʼs surface into smaller and smaller pieces.• Produces boulders, pebbles, dust, etc.

Mechanical weathering• Water - freezes (expands) in rock cracks and splits

the rock• Plants - Seeds fall into rock cracks and split rocks

as they grow

Chemical Weathering

• Alters a rockʼs chemical makeup• Can change one kind of rock to a completely different kind!•Acid rain - water & carbon dioxide mix and dissolve rock

Acid Rain

Erosion

• The movement of weathered material such as gravel, soil, and sand• Caused by water, wind, & glaciers

Water Erosion• Moving water and

sediment wear away rock• Worn away rock and soil

is deposited in flood plains or deltas• Nile River delta à

Examples of Water Erosion

•Grand Canyon

Wind Erosion• Particularly severe in dry areas with little vegetation.

Glacial Erosion

• Glacier – a huge slow-moving sheet of ice• Moraine – ridge-like pile of debris left behind by a melted glacier

MoraineinStutsmanCounty

HumanActions

• Mining• Constructionoftunnels,canals,farms• Pollution• ChangestotheEarthbyhumanactionsareoftenmuchfasterthanbynature

Chapter2,Lesson3LandandWater

70% of the earth is covered by water!Pg.58-65

The Water Cycle• The total amount of water in the world doesn’t

change• Water Cycle:• water moves from oceansà air à ground à oceans

How the Water Cycle works

• Evaporation – the sun’s heat turns liquid water in the ocean into water vapor• Condensation – water vapor cools and changes back to a liquid• Precipitation – rain, snow, sleet, hail• Collection – precipitation flows into streams & rivers and back into

the ocean

Types of Water Resources

• Saltwater – 97%• Oceans• Seas• Gulfs• Bays• Straits

• Desalination – removing salt from the water to make it drinkable

• Freshwater – 3%• Glaciers (polar ice caps)• Lakes• Rivers• Groundwater

Our water resources are

limited!

Water Scarcity

• What causes it?• Pollution• Drought/dry conditions• Over-irrigation• Wasting/overuse