Unit 2

Question 1

Ancient Greek philosophers

Answer 1

– Spherical shape

• 350 BCE

Question 2

Eratosthenes

Answer 2

– Accurately estimated Earth’s
circumference
• 200 BCE

Question 3

Ellipsoid Earth

Answer 3

– Similar to a sphere, but with a bulge around the center (Equator)
• Earth is not a perfect “Ellipsoid”
– Rugged terrain
• Mt. Everest (8.8 km above sea level)
• Marianas Trench (10.9 km below sea 
level)

Question 4

spheres of the earth

Answer 4

• Atmosphere
• Lithosphere
• Hydrosphere
• Cryosphere
• Biosphere
• Hemisphere

Question 5

Atmosphere

Answer 5

– Blanket of air that adheres to the 
Earth’s surface
– Ranges from a few meters below 
the surface to 60,000 km (37,000 
mi)
– In continuous motion due to solar 
energy

Question 6

Lithosphere

Answer 6

– Outermost shell of the solid Earth
– Forms Earth’s scenery
• Mountains
• Valleys
• Seafloor

Question 7

Hydrosphere

Answer 7

– All of the liquid water on the
Earth’s surface and in the
atmosphere
– 71% of the Earth’s surface

Question 8

Cryosphere

Answer 8

– All of the frozen water including
glaciers, floating ice, snow cover,
and permafrost

Question 9

Biosphere

Answer 9

– Zone of life

– Includes vegetation and animals

Question 10

Hemisphere

Answer 10

– Hemi –meaning half

– Sphaira –meaning sphere

Question 11

equator

Answer 11

Imaginary line that circles the earth at zero degrees latitude

Question 12

prime meridian

Answer 12

– Imaginary line that runs from the North Pole to the South Pole and passes through Greenwich, England

Question 13

international date line

Answer 13

– Imaginary line that runs from the North Pole to the South Pole and passes through the Pacific Ocean

Question 14

northern hemisphere

Answer 14

– From Equator to the North Pole

– 70% of Earth’s land area

Question 15

southern hemisphere

Answer 15

– From Equator to the South Pole

– Dominated by water

Question 16

western hemisphere

Answer 16

– Extends from the Prime Meridian
westward to the International
Date Line

Question 17

eastern hemisphere

Answer 17

– Extends from the Prime Meridian
eastward to the International
Date Line

Question 18

cartography

Answer 18

– The science, art, and
technology of mapmaking and
map use

Question 19

Location

Answer 19

– A grid is formed on the Earth’s 
surface as lines run both E-W 
and N-S
•Lines form great circles and 
small circles

Question 20

great circle

Answer 20

– Plane that passes through the center 
of a sphere dividing it in half
– Represents the circumference of a 
sphere
– Ex: Circle of Illumination

Question 21

small circle

Answer 21

– Plane that passes through any other
part of a sphere than the center
– Ex: Tropic of Cancer

Question 22

lines of latitude

Answer 22

– Run E-W around the Earth
•Measure N/S component of a
location

Question 23

lines of longitude

Answer 23

– Run N-S around the Earth
•Measure E/W component of a
location

Question 24

conversion equations

Answer 24

– To convert from minutes and seconds to decimal form:
•Divide seconds by 3,600 and divide minutes by 60 and add the two
– To convert from decimal to degrees and seconds:
•Multiply decimal by 60. Whole number is minutes. Multiply the remaining
decimal by 60. That is the number of seconds

Question 25

elevation

Answer 25

``` – Height above some reference value (i.e. vertical datum) – Distance above mean sea level (AMSL) • Use average to eliminate tidal and other effects ```

Question 26

GPS

Answer 26

– Easy way to determine location – Relies on a network of 24 satellites, which are in geosynchronous orbit – Uses signals from these satellites

Question 27

Map Projections

Answer 27

– Project Earth and its “lines” onto a surface to create a 2D map •Will be errors!

Question 28

conformal

Answer 28

– Map projection that preserves the true shape – Area is not preserved -mercator

Question 29

equal area

Answer 29

– Map projection that preserves the true area – Shape is not preserved -peters

Question 30

cylindrical map projections

Answer 30

``` •Transfer of Earth’s latitude and longitude grid from a globe to a cylinder •Ex: Mercator Projection – Most popular cylindrical projection – Any straight line is a line of true and straight compass bearing ```

Question 31

conic map projection

Answer 31

``` – Conic •Transfer of Earth’s latitude and longitude grid from a globe to a cone •Typically used in mid-latitudes that cover a large expansion of longitudes ```

Question 32

Standard parallel

Answer 32

``` – The line of latitude where the projection surface touches the globe – Found in conic or cylindrical projections •Tangent: 1 standard parallel •Secant: 2 standard parallels ```

Question 33

planar map projections

Answer 33

– Planar •Imaginary plane that touches the globe at a single point •Typically used for polar regions

Question 34

mathematical map projections

Answer 34

•No projection surface •Minimize distortion – Devote most of the projection to the parts that project best – Deemphasize areas of the globe that are not essentia

Question 35

scale

Answer 35

– Ratio of map distance to Earth distance – Should always be 1:some #

Question 36

small scale

Answer 36

– Shows large area with less detail (i.e. world map) – Large denominator (1:75,000,000)

Question 37

large scale

Answer 37

– Shows small area with great detail (i.e. hiking map) – Small denominator (1:7,500

Question 38

Isopleth (Isolines)

Answer 38

– Depict surfaces – “iso” means equal – Numerous lines that represent points of equal value

Question 39

Contouring (contour lines)

Answer 39

– Measure elevation – Each contour line represents an elevation value

Question 40

isotherms

Answer 40

– Measure temperature – Each line represents a temperature value

Question 41

gis

Answer 41

``` – A grouping of computer software and hardware – Enables spatial data to be collected, analyzed, stored, retrieved, manipulated, and displayed – A lot of spatial data collected using remote sensing techniques – “Interactive Mapping ```

Question 42

remote sensing

Answer 42

``` – Ability to scan the Earth from airborne and satellite observation platforms to gain information •Examples: – Elevation – Cloud cover – Vegetation – Infrastructure ```