GEOG 1112 Lecture 2 Notes

Earth is not a perfect sphere because…

it has a geoidal bulge at the equator

Where is the geoidal bulge located?

at the equator

what grid system is used to locate things on Earth?

latitude and longitude system

parallels of latitude are the lines that run…

East to West

how are latitude lines measured?

they are parallel and measured North or South, starting at 0 degrees (the equator) and ending at 90 degrees (the N & S poles)

Meridians of Longitude are the lines that run…

North to South

how are the Meridians of Longitude measured?

they are non-parallel and are measured East or West, starting at 0 degrees (the equator) and ending at 180 degrees (the International Date Line)

What can the degrees of latitude and longitude be subdivided into?

they can be subdivided into minutes and seconds

What is a degree?

A degree is a part of a circle, with 360 parts of degrees in a complete circle.

How much can a degree be sub-divided further?

a degree can be further sub-divided into 60 equal parts or minutes, and a minute is further subdivided into 60 equal parts or seconds.

What does this mean: 12 degrees, 35’ 15’’N 104 degrees, 55’ 30’’E

12 degrees, 35 minutes, 15 seconds North and 104 degrees, 55 minutes, 30 seconds East

when writing positions latitude and longitude coordinates, what is the correct order?

Latitude is written first and then longitude after

Major lines of latitude

1. equator (0 degrees)

2. Tropic of Cancer (23.5 degrees N)

3. Tropic of Capricorn (23.5 degrees S)

4. Arctic Circle (66.5 degrees N)

5. Antarctic Circle (66.5 degrees S)

6. North Pole (90 degrees N)

7. South Pole (90 degrees S)

major lines of longitude

1. Prime Meridian (0 degrees)

2. International Date Line (180 degrees)

Equator

0 degrees

Tropic of Cancer

23.5 degrees N

Tropic of Capricorn

23.5 degrees S

Arctic Circle

66.5 degrees N

Antarctic Circle

66.5 degrees S

North Pole

90 degrees N

South Pole

90 degrees S

Prime Meridian

0 degrees

International Date Line

180 degrees

What determines Earth’s Time Zones?

Earth’s rotation & Meridians of Longitude

Greenwich Mean Time (GMT) refers to

the local time in London, England (Greenwich)

How can difference in time be determined between time zones?

by knowing the longitude of each location.

transferring 3D objects onto flat 2D surfaces can cause

distortion of the physical size and shape of the area represented.

What is the scale of a map?

the ratio distance on the map to the actual distance on the ground

Different types of scales?

1. written scale

2. representative fraction

3. graphic (bar) scale

What would a written scale look like?

One inch equals four miles (means that 1 inch on the map equals 4 miles on the ground)

What would a representative fraction look like?

1:24,000 (which means that 1 inch on the map equals 24,000 inches (2,000 feet on the ground)

What does a graphic scale look like?

a line marked at intervals to show the distance on the earth which the distance on the scale represents.

Maps can be classified as…

small, medium, or large scales

A large scale map (1:24,000) shows a

relatively small area of the Earth’s surface

more detail

A small scale Map (1:1000000) shows a…

relatively large area of the Earth’s surface

less detail

Types of Maps

1. topographic

2. road maps

3. nautical charts

4. weather maps

5. thematic maps

What are thematic maps?

they show the distribution of a phenomena (climate, language, religion), or show relationships between places (population, economic activity, transportation routes)

What is the most common type of map used in Geography?

Thematic Maps

Spacial distribution is

the arrangement on the landscape of the feature being studied.

must also answer why is that distribution the way it is, what causes it.

What are the 3 aspects or properties of spatial distribution?

1. density

2. concentration

3. pattern

density refers to

the frequency with which a feature/phenomenon occurs within a given area

What is concentration of a feature/phenomenon?

Concentration of a feature/phenomenon is the arrangement or spread of that feature over a unit of area

What is a Pattern of the feature/phenomenon?

Refers to the geometric arrangement of that feature across the landscape.

What is a mental map?

mental map is the image in your mind (the cognitive image) of a particular area, place or route

What is involved in a mental map?

it involves the idea of environmental perception, your memories (sights, sounds, smells) of a place or route.