Lecture 3 + Chapter 3

Question 1

what is a map scale

Answer 1

measures how much the features of the world as reduced in size to fit on a map
- large scale maps = more detail
- small scale maps = larger area with less detail
1:625000

Question 2

What are the 3 different map scale types

Answer 2

1. Representative fraction (1: 6500)
2. Graphic scale (image)
3. Verbal description (one cm = one mile)

Question 3

Cartesian Coordinates

Answer 3

• uses x and y axes to define a point on a 2-dimensional plane
• (3,2) represents a point on a grid

Question 4

What is extent

Answer 4

• the area of the earth that is visible on the map
  the extent of a map would be everything that is shown on the map
  the resolution would be the smallest unit that is mapped (will tell you in the title)
  “Life expectancy by US country, 2024

Question 5

Geographic Coordinates

Answer 5

cartesian system that is adjusted to deal with the Earth’s spherical nature
- longitude (east-west lines)
- latitude (north-south lines)

Question 6

what is the graticule

Answer 6

the network of lines representing latitude and longitude - used to locate positions on earth

Question 7

what is a projection

Answer 7

turning a 3-dimensional globe into a 2-dimensional map
- multiple issues - not perfectly possible without shearing, compressing, tearing
** All projections distort shape, area, or distance - the best is based off of your preference

Question 8

what are the developable surfaces of a projection

Answer 8

the surface that the globe is being transformed on to
- plane, cone, cylinder

Question 9

what is a tangent point or line on a projection

Answer 9

the place where the developable surface touches the globe
will be the most accurate here
(cone - more accurate around circumference, plane will be the most accurate on one point)

Question 10

What are the projection mechanics

Answer 10

conformal projections
equal area projections
equidistant projections
interrupted projection
comprise projection
artistic projections

Question 11

Explain conformal projections

Answer 11

good shape and angle but distorts the area near the poles (much larger) - Antarctica is very large in this projection
EX: Mercator Projection

Question 12

Explain equal area projection

Answer 12

projections that preserve are and angle but distort shape
- EX: Gall Peters
- countries seem to be stretched elongated

Question 13

Explain equidistant projection

Answer 13

projections that preserve distance along only a few specified lines
- used to visualize airplane flight paths from city to city
EX: azimuthal equidistant projection

Question 14

Explain compromise projections

Answer 14

projections that have a balance of distortion between area, shape and angle
- they do not preserve any property
- often used for small-scale thematic maps around the world
- EX: Robinson projection
- focuses on aesthetic but not good for analysis and measurement

Question 15

Explain interrupted projection

Answer 15

projections that tear the earth in strategic places to reduce the shape and area distortion
- preserves shape and angle but distorts DISTANCES
EX: goode homolosine projection
(cuts in the waters - unknown distances from continent to continent

Question 16

explain the artistic projection

Answer 16

• projections that are used for aesthetics/pleasing
• not intended for measurement/navigation/data
  EX: Stabius-Werner projection

Question 17

What is the best projection

Answer 17

all maps distort - all maps are wrong - they just do it in different ways
- the best projection is based on what you like and what you are doing with the map

Question 18

what are 3 common projection systems

Answer 18

1. cylindrical (least distortion near equator)
2. conic (cone shape - distortion at poles)
3. azimuthal (onto a plane)