Intro to Mapping and GIS
Card Set Information
Intro to Mapping and GIS
cartography maps GIS
Test 1 Mapping and GIS
What is a cartography map?
a graphic representation of the environment
Name 3 reasons why maps aren't as simple as they seem
Rapid changes in technology
colors without plans
What does it mean when I say 'dubious' quality?
poorly selected symbol sealing
inappropriate symbolization for the data
Why are maps used?
strong visual impact
convenient to use
simply the infromation
What is a chloroplata map?
where each polygon is assigned a color
what is a reference map?
a map that shows a variety of features of the world as a portion
What is a thematic map?
a map that demonstrates particular features or concepts
shows distribution of a single attribute or a relatioship among several
What are the two kinds of thematic maps?
What do qualitative maps show?
the spatial distribution or location of kind (nominal data)
What do qualntitative maps show?
the spatial aspects of numerical data (ex. Vote, income, cancer)
What are persuasive maps do?
they exaggerate some parts of a map (ex. MARTA map)
What do aeronautical charts display?
instrument navigation (eg. road)
The name of the Earth as an irregularly shaped body
Explain the existence of the Tropics of Cancer and Capricorn.
The northern and southernmost positions where the sun is directly overhead
The North-South angular distance from the equator to the point of interest
Angle from the Prime Meridian to the meridian passing through the point of interest
What is the decimal degrees formula?
DD + MM/60 + SS/3600
Convert 25*32'5" to the decimal degrees.
A mathematical model of the Earth, serving as the reference for calculating the geographic coordinates of a location
The equatorial axis
WHy do different countries use various reference ellipsoid?
The reference ellipsoid used before the 1960's
NAD27 Meaded Ranch, KS
the more acccurate reference ellipsoid
NAD83 no single physical initial point
WHen are nautical miles used?
maritime and aviation purposes
1 nautical mile equals
Statute miles are used for
land distances on U.S.
1 statute mile equals
Great circles are _______.
the largest possible circles on the surface of the spherical earth
WHat is the general understanding of great circles?
any meridian can be a great circle
What is a map scale?
the ratio between a map and ground distance
WHat is a typical scale of a large map?
1:1,250,000 (or larger)
WHat are three features that comprises scale bars to map scales in terms of verbal and ratio scales?
scale bar changes size in direct proportion to the physical size of the map
stacked scale bar
easy to figure distances
A scale that varies systematically in the North-South direction (along Parallels)
variable scale bar
A mathematical transformation of a 3D map to a 2D map
The ratio of actual scale compared to principle scale
If you dont have any changes to your map, what is your scale factor?
What is meant by conformal property?
preserving the original shapes
scales of the projection in the x and y direction are always equal
What is azimuthal property?
Preservation of directions
What is equidistance property?
Preserving distances from one point to another
A line of tangency between the projection surface and the globe; no distortion
What is an example of a Cylindrical Family Projection?
Oblique Mercator map
What are the standard lines in Conic Family Projections?
What is an example of a Conic Family Projection?
An east-west extent map (Continental United States map)
What does UTM stand for?
Universal Transverse Mercator
What does SPC stand for?
State Plane Coordinate
Describe tangent case planes.
There is one line of tangency in the middle
no distortion on either ends
Describe secant case planes.
there are two lines of distortion
the least distortion will be above and below the lines of tangency
Which vector data attributes are ranked from least to most and has meaningless orders?
Which vector data attributes use letters and numbers to label objects?
WHich three figures does vector data use to represent spatial features?
WHich vector data attribute have differences between ranks that actually make sense?
Which vector data attribute contains distance and ratios differences that make sense?
How do we classify equal intervals?
(max-min) / number of classes
How are quantiles classified and shown on a map?
total observations/number of classes
data is ranked and equal numbers of observations are placed in each class