CARTOGRAPHIC BASICS

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GIS IS NOT CARTOGRAPHY
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CARTOGRAPHIC BASICS

• Maps perform two important functions
• Storage medium for information that humanity
  needs
• Provides a picture of the world to help
  understand spatial
• patterns, relationships, and environmental
  complexity
• Maps tell us
• Where is it?
• What is it?
• (often) When is it?
• What is nearby? How far away? In which
  direction? How
• do I get there?
• What other things are there also?
• How might they be related?

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CARTOGRAPHIC BASICS
Where am I? After James R. Smith, page 46 How
far to my destination? In what direction do I
go? How large? What shape?
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CARTOGRAPHIC BASICS

• All maps have the same goal
• Communicating spatial relationships
• Communicating the form of the landscape
• Basic characteristics of all maps
• Location
• Attribution
• Reduction of reality
• Scale
• Geometrical transformation/projection
• Abstractions of reality
• Symbolism

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CARTOGRAPHIC BASICS

• Location and Attribution allow many types of
  relationships
• to be formed
• Relationships among locations with no
  attributes
• distance, bearing
• Relationship among various attributes at the
  same point
• Relationship among different locations of the
  same attribute
• Relationships among locations of
  combined/derived
• attributes of given distributions --
  spatial distribution
• of per capita income vs. educational
  attainment

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CARTOGRAPHIC BASICS

• Classification of maps
• Classed by Scale
• Small scale
• Medium scale
• Large scale
• Classed by Function
• General reference maps
• Thematic/special purpose maps
• Charts
• Classed by Subject Matter
• Cadastral maps
• Plans
• Soil, vegetation, precipitation, etc.
• The principal task of cartography is to
  communicate
• environmental information. The task of the map
  designer is to enhance the map user's ability to
  retrieve information.

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CARTOGRAPHIC BASICS

• Mapping involves information transformations
• Data collection
• Selection
• Classification
• Simplification
• Exaggeration
• Symbolization
• Use of map
• The cartographer's task - explore the
  ramifications of each
• mapping possibility and choose the most
  appropriate for the
• intended task. Who is your audience?

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CARTOGRAPHIC BASICS

• Four main cartographic processes
• Collecting and selecting data for mapping
• Manipulating and generalizing the data,
  designing and
• constructing the map
• Reading or viewing the map
• Interpreting the information presented on the
  map
• Skilled cartographers must be familiar with all
  mapping activities, including geodesy, surveying,
  photogrammetry, remote sensing, GIS.
• Skilled cartographers must be familiar with the
  principals of human thought and communication.
• Skilled cartographers must be familiar with the
  disciplines associated with the environmental
  features being mapped.

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HISTORY OF CARTOGRAPHY

• Changing ideas about cartography
• Earliest maps are figurative, ceremonial,
  artistic
• 100 A.D. the Greeks develop concepts of
  geometry
• 1200 A.D. - 'church maps' of the Dark Ages
• 1300 A.D. - Renaissance brings major expansion
  of world
• knowledge, travel
• 1680 AD the Enlightenment concept of
  'Western science'
• and concern with positional accuracy
• 1800s place gt space concept of
  distribution thematic maps
• come into being environmental data becomes
  important
• 1950 - systems approach to the environment gt
  reintegration
• of themes and concept of cartographic
  modeling

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HISTORY OF CARTOGRAPHY
100 A.D. geometry 1200 Dark Ages 1300
Renaissance 1680 Enlightenment 1800s Place gt
Space 1950 -- Systems Approach
From Robinson, Sixth Edition, page 22
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HISTORY OF CARTOGRAPHY

• Constant goal
• Society demands maps that are timely, accurate
  and complete. There has been a continual demand
  for greater accessibility to lower cost maps.
  Cartographers' constant struggle with these
  demands leads to evolution of maps
• Changing technology
• Manual techniques are still used today
• 12th century magnetic compass
• 16th century mechanical printing press
• 17th century optical technology
• 19th century photo-chemical technology
• 1950 electronic/computer technology
• The success of computer-assisted mapping rests on
  the skill of the cartographer and development/
  application of computer system components within
  a cartographic environment.

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HISTORY OF CARTOGRAPHY
Magnetic Compass Mechanical Printing
Press Lens Grinding, Telescope Lenses,
Lasers Photography, Lithography Computer
Technology
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BASIC GEODESY

• Geodesy is the science that determines the
  figure of the
• earth and the interrelation of selected points on
  its surface
• by either direct or indirect techniques.
• Mapping involves determining the geographic
  locations
• of features on the earth, transforming these
  locations into
• positions on a flat map through the use of map
  projection,
• and graphically symbolizing these features.
• Cursed be he who moves his neighbors boundary
  stone.

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BASIC GEODESY

• The earth is not round
• Authalic sphere a sphere with the same
  surface area as
• the ellipsoid used as base figure for
  mapping.
• WGS 72 and 84 ellipsoids based on satellite
  orbital data
• Clarke 1866 ellipsoid used for mapping in
  North America
• (based on ground measurements made in
  Europe, India,
• Peru, Russia, South Africa)
• Geoid is a more faithful figure of the earth
  3D shape
• approximated by mean sea level in the
  oceans and the
• surface of a series of sea-level canals
  crisscrossing the
• continents.

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BASIC GEODESY

• Cartographic use of sphere, ellipsoid, geoid
• Authalic sphere used for small scale maps of
  countries,
• continents, larger areas
• Ellipsoid used for large scale maps such as
  topographic
• maps and nautical charts GPS systems use
  ellipsoid
• Geoid used as reference surface for ground
  surveyed
• horizontal and vertical positions
  elevations determined
• relative to mean sea level geoid

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BASIC GEODESY
From James R. Smith, page 34
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BASIC GEODESY
After James R. Smith, page 52
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BASIC GEODESY

• Direction on the earth
• Geographic/true directions determined by the
  orientation of
• the graticule on the earths' surface
• Magnetic directions must take into account the
  compass
• variation/magnetic declination
• True azimuth clockwise angle a great circle
  makes with the
• meridan at point of origin (changes
  constantly along the arc)
• great circles shortest distance between
  points
• Constant azimuth line which makes a fixed
  angle with all
• meridians (rhumb line or loxodrome)
  spirals to pole