WORLD GEOGRAPHY

Welcome to

Textbook?World Geography Pre-AP World Geography

Exploring

Geography

Unit 1

Chapter 1

Section 1: What is Geography?

A. 2 Definitions

1. The study of the physical, biological, and cultural features of the earth’s surface (Holt)

2. The study of where people, places, and things are located and how they relate to each other (PH)

• study of distribution and characteristics of the world’s people (where people live and what they do)

• examines how people make and trade things that they need to survive

• focuses on Earth’s natural environments including landforms, water features, plants, animals, and other physical features

• studies the processes that shape physical environment

• interaction of people with their

environments

Human Geography

Physical Geography

Both

Themes and Essential ElementsB. Two Branches of Geography

1. Physical Geography 2. Human Geography

C. Geographic Tools

1. Technology

a. Sonar: analyzes sounds to determine distance & location.

Geographic use of sonar: study ocean floor

b. Satellites: ex Landsat 7 - records images of earth's surface.

Geographic use of satellites: compare older/recent images to identify

changes in land use, vegetation, urban growth

Satellite images show the shrinking ARAL SEA

Aral Sea

c. GPS (global positioning system: uses 24 orbiting satellites; Use atomic clocks to send back extremely accurate time measurements to provide info

about location

d. GIS (geographic information system): a computer system that stores, displays, and maps

locations and their features – information is layered to show relationships among data – layers can be placed together in a multitude of combos to create many different maps, unique and suitable to individual queries

GIS “layering”

2. Maps!

a. Organizing the Globe

A globe is a scale model of the earth

- useful for looking at the whole planet or large areas of

land/water

b. Grid – pattern of lines on the globe in E-W/N-S directions

Latitude: lines running E-W

Longitude: lines running N-S

- intersection of these imaginary lines

help us fine ABSOLUTE location of

places

c. Measuring Latitude & Longitude

1) Latitude (also called parallels): E-W» Imaginary lines that run parallel to equator» Lines run E-W, but measure distance north or south of equator» Equator = 0º» North pole = 90ºN» South pole = 90ºS» Tropic of Cancer = 23 ½ ºN» Tropic of Capricorn = 23 ½ ºS» (tropics receive most direct sunlight/greatest heat energy from the sun)» Lines of latitude, or parallels are parallel to e/o

Think of latitude like the rungs of a ladder (ladder sounds a lot like latitude). Latitude lines run east and west, but they tell how far up (north) you can go or how far down (south) you can go.

2) Longitude (also called meridians):» Imaginary lines which run North & South btwn poles

» Lines run N-S, but measures distance east or west of Prime Meridian

» Prime Meridian = 0º (through Greenwich, England)» All other meridians are measured in degrees from 0 to 180 E or W

from Greenwich» Lines of longitude, or meridians, are not parallel to e/o

When you think of longitude, think of long, tall telephone poles (because longitude lines run from pole to pole). Longitude lines run north and south, but they tell how far east you can go or how far west you can go.

Practice – Latitude, LongitudeExample: 60ºS, 110ºE

a

b

Ex

c

d

e

f

g

h

Practice – Latitude, LongitudeExample: 60ºS, 110ºE

a. 50ºN, 100ºW c. 40ºS, 30ºE e. 40ºS, 130ºW g. 0º, 0º

b. 10ºN, 30ºW d. 30ºN, 100ºE f. 70ºN, 5ºE h. 25ºS, 135ºE

a

b

Ex

c

d

e

f

g

h

d. The Earth is divided into 4 hemispheres

In which hemisphere(s) do you live?

e. Map projections- b/c our planet is round, ALL flat maps have some distortion1) Conic projection

Map Projection

cylindrical

conic

flat-plane

Advantages

used by navigators because it show true direction and shape

accurate for area with long east-west dimensions

used by pilots and navigators because it shows true direction, area, and sizes

Disadvantages

exaggerates land masses at high altitudes

not as accurate for areas that extend mostly north to south

distorts shapes

-advantages/disadvantages of map projections

f. Map Elements1) Distance Scales: used to determine REAL

distances btwn points on a map- maps of small areas can show more

detail than maps of large areas

2) Directional indicators- shows which directions on a map are N, S,

E, or W- most maps have north at the top

Compass Rose

North Arrow

3) Legends (aka key)

- identifies symbols on a map and what they represent

4) Inset Map

- used to focus in on a small part of a larger map

D. Five Themes of Geography1. Location

– Where is it?

a. Absolute location is given in degrees of latitude and longitude

b. Relative location depends upon point of reference (near, far, south, north etc.)

- Montgomery High School is east of

Dobbin

2. Place- What is it like there? What are the characteristics?a. Physical Characteristics – landforms (mountains, plains, etc.),– bodies of water (oceans, lakes, bay, etc.)– ecosystems (soil, plants, animals etc.)– climate (tropical, arctic etc.)

b. Human Characteristics – bridges, roads, buildings– Language, customs, culture– Economy – where/how do they work?

- All places have features that distinguish them from other places.

3. Regions- How are places similar to other places? What

are their unifying features?- a region is an area with one or more common

featuresa. Formal Region: a characteristic found

throughout an area- political: areas same laws/gov’t- climate: areas with similar climate

b. Functional Region- central place + surrounding places affected by it- ex: city + suburbs; river basin

c. Perceptual Region- defined by people’s feelings or attitudes

about an area (don’t have precise borders)- ex: south = Dixie; the boonies

4. Movement- How do people, goods and ideas move between places?a. Transportation/communication/tradeb. Migration (temporary or permanent)c. Linkage/connection

5. Human-Environment Interaction- How do people interact with the environment of a place?a. How do they adapt to it?

b. How do they modify it? Consequences?

c. How do they depend on it?

• Human beings have made enormous changes in their environment, both intentional and accidental.

- Changes to the environment can be favorable, making some places more habitable.

- Changes can also be destructive, altering an area’s ecosystem and straining local resources.

Section 2: Changes within the Earth

A. Physical Characteristics

- using Geology (study of earth’s physical structure & history), scientists try to identify changes in/on the earth, explain causes & effects & predict future changes.

1. The Earth’s Layers

a. Core: center of the earth; consists mostly of iron + some nickel

1) inner core: dense & solid

2) outer core: liquid

b. Mantle: layer of thick, dense rock

c. Crust: thin, rocky surface layer

1) thinnest below oceans (~4mi.)

2) thicker (avg 22 mi.) beneath continents

3) natural forces act on crust creating landforms etc

2. Land, Air & Water

a. Lithosphere: land that makes up the earth’s crust

1) ~30% of earth’s surface is land

2) continents (7 lrg land masses), islands, ocean floor

3) landforms (classified according to relief – diff. in elevation btwn high/low points),

soil, rocks

- see landform chart (mts, hills, plateaus, plains, valleys, canyons,

basins, peninsulas, etc

b. Atmosphere: air, water, etc. above earth’s surface

1) extends about 1000 mi. above earth’s surface

2) 78% nitrogen, 21% oxygen, + carbon dioxide & other gasses

3) sustain life on earth4) protect planet from Sun’s harmful

radiationc. Hydrosphere: all of earth’s water

1) covers ~ 70% earth’s surface2) not found on other planets in the

solar system

d. Biosphere: part of earth where life is found

- all people, plants & animals

- all sphere’s are interconnected – what happens in one, affects the other(s)

B. Physical Processes

- landforms are shaped by internal forces that originate in earth’s interior

1. Volcanoes

a. Form when magma breaks through the earth’s crust. Molten rock is called

lava when it reaches the surface

b. The shape of volcano depends on type of eruption

1) shield: even flow of lava

2) cone: caused by sequence of explosive eruptions

2. Movement in the Crust

a. Fold: result when rock layers bend & buckle

b. Fault: a break in earth’s crust caused by stress on rocks

c. Earthquakes: caused by large sudden movement along a fault

C. Understanding the Past

- common belief that the earth’s landmasses have broken apart, rejoined & moved to other parts of the globe

1. Plate Tectonics

a. Earth’s crust + brittle, upper layer of mantle is broken into a # of moving plates. These

plates slide over a hot & flexible layer of the mantle

b. Earth’s oceans & continents ride over atop plates as they move in different directions

c. Most eqs, volcanoes & other geologic events occur along plate boundaries

Plate Tectonics

2. Continental Drift

a. once a “supercontinent” (Pangea) which broke apart 180 m yrs ago

b. Theory supported by fossil evidence & “puzzle pieces”

3. Seafloor spreading

a. Ocean floor not flat. Landforms like earth’s surface. Ocean rocks younger than continental rocks

b. Theory: molten rock from mantle rises beneath underwater ridge & breaks through a split, called a rift valley. Rock spreads out in both directions. As seafloor moves away from ridge, it carries older rocks away

Atlantic Ocean – 2-3 cm/year

South Pacific Ocean – 15-18 cm/year

Speed of Spreading

4. Plate Movement

a. Plates move via convection: a circular mvmt caused when a material is heated, expands & rises, then cools & falls

b. Heat energy probably comes from slow decay of material under the crust

5. When Plates Meet -plates can spread apart, crash into e/o, slide past e/o

a. Divergent plate boundary – plates pull away from e/o

b. Convergent plate boundary – dense ocean crust slides beneath continental crust

c. Transform plate boundary – slide past e/o

6. Ring of Fire – circle of volcanoes surrounding Pacific Ocean – plate boundaries

7. Other Geologic Processes

a. Volcanic hot spots – formed by “hot spots” deep w/in earth’s surface. When molten rock flows out of a crack in earth’s surface, volcanic island chain produced as plate drifts over stationary hot spot

b. Geysers – formed when molten rock rises from a hot spot heating underground water

Sec. 3:Changes on the Earth’s SurfaceA. Weathering - the breakdown of rock at or near

the earth’s surface into smaller & smaller pieces called sediment (mud, sand, silt)

1. Mechanical Weathering

a. Occurs when rock is broken or weakened b. Changes size – NOT composition

1) Frost Wedging most common – when ice crystals build up/expand in cracks of rock & create enough pressure to fracture rock into smaller pieces

2) organic activity: root pry, burrowing animals, human activity

3) Gravity: rocks falling and

colliding w/ others

2. Chemical Weathering

a. occurs when rock is changed into a new substance as a result of interaction btwn elements in the air or water & the minerals

in a rock

b. Can change one type of rock into a diff. kindc. Agents of Chemical Weathering

1) water – dissolves minerals out of rocks making them weaker

2) acid - dissolves minerals in rocks (examples: carbonic acid, acid rain,

and plant acid)

3) oxidation- Oxygen combines with iron minerals and sulfur minerals changing the composition of the rock

d. Acid Rain – chemicals in polluted water combine w/ water vapor – falls back to

earth as acid rain

3000 year old Egyptian Obelisk

3000 year old Egyptian Obelisk after 100 years in

NY

Acid Rain in Action

Acid Rain in Action

B. Erosion - the mvmt of weathered material such as sand, soil, gravel to be moved by action of wind, water, ice or gravity

** significant agent in mechanical weathering and soil building!

1. Water

a. Greatest cause of erosion = moving water such as rain, rivers, streams, &

oceans

b. New landforms created as sediment settles with slowing water Alluvial fan

Water Erosion in Action

2. Wind

a. Vulnerable in areas w/ little water, few plants to hold soil in place

b. Benefits? Deposits loess – wind-blown mineral rich silt & clay deposits that

produce very fertile soil

c. Can be major form of erosion – windblown sand carves or smoothes surface of rock

formations & man-made objects

Dust storm approaching

Stafford, TX 1930s

Wind Erosion in Action

3. Glaciers – huge slow-moving sheets of ice formed over many yrs that move b/c of great weight + gravity

a. Glacial landscape diff. from water shaped landscape

1) Rivers = V shaped valleys

2) Glaciers = U shaped valleys

b. Carved out Great Lakes & more

c. Today, fewer glaciers. 80% of Greenland, most of Antarctica – chunks break off to produce floating icebergs

d. Degree of glacial erosion depends on size & speed of glacier + terrain & texture of bedrock being covered

e. Alpine Glaciers – found all over on high mts