GIS IS NOT CARTOGRAPHY. 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:
patterns, relationships, and environmental complexity
Maps tell us:
do I get there?
Where am I? After James R. Smith, page 46
How far to my destination?
In what direction do I go?
Basic characteristics of all maps:
attributes of given distributions -- spatial distribution
of per capita income vs. educational attainment
General reference maps
Thematic/special purpose maps
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.
The cartographer's task - explore the ramifications of each
mapping possibility and choose the most appropriate for the
intended task. Who is your audience?
Four main cartographic processes:
constructing 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.
and concern with positional accuracy
come into being; environmental data becomes important
of themes and concept of cartographic modeling
100 A.D. – geometry
1200 – Dark Ages
1300 – Renaissance
1680 – Enlightenment
1800s – Place => Space
1950+ -- Systems Approach
From Robinson, Sixth Edition, page 22
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
The success of computer-assisted mapping rests on the skill of the cartographer and development/ application of computer system components within a cartographic environment.
Mechanical Printing Press
Lens Grinding, Telescope Lenses, Lasers
“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 neighbor’s boundary stone.”
the ellipsoid – used as base figure for mapping.
(based on ground measurements made in Europe, India,
Peru, Russia, South Africa)
approximated by mean sea level in the oceans and the
surface of a series of sea-level canals crisscrossing the
Cartographic use of sphere, ellipsoid, geoid:
continents, larger areas
maps and nautical charts; GPS systems use ellipsoid
horizontal and vertical positions; elevations determined
relative to mean sea level geoid
From James R. Smith, page 34
After James R. Smith, page 52
the graticule on the earths' surface
meridan at point of origin (changes constantly along the arc)
great circles = shortest distance between points
meridians (rhumb line or loxodrome); spirals to pole