1. GUS: 0262 Fundamentals of GIS Lecture Presentation 2: Cartography in a Nutshell Jeremy Mennis Department of Geography and Urban Studies Temple University

2. Maps as Models Maps are models of reality. They emphasize some aspects of reality in a cartographic representation while ignoring or greatly simplifying other aspects of reality.

3. Scale the amount of reduction in the representation of a real world geographic phenomenon on a map. or, the ratio of map distance to earth distance 1:24,000 1 inch = 2000 ft 1 2000 ft verbal scale representative fraction bar scale

4. Geometric Representation Points Lines Polygons

5. Generalization

7. Measurement Levels Nominal: equivalence eg. land cover (residential, industrial) Ordinal: ranking e.g. city size (small, large) Interval: ratio assuming an arbitrary 0 value e.g. temperature in degrees F Ratio: ratio assuming a true 0 value e.g. temperature in degrees K

8. Map Projections a means to depict the spherical earth on a two dimensional medium cannot simultaneously preserve all of these properties of the earth in two dimensions: shape (of a region) distance (between two points) direction (bearing from one point to another) area (of a region)

9. Map Projections

10. Conformal projection preserves direction e.g. Mercator Equal area projection preserves area e.g. Alber’s equal area

11. Geoid and Datum Geoid: a model of the earth’s shape Clarke 1866 GRS80 Datum: reference point for establishing horizontal control NAD27 uses Clarke 1866 NAD83 uses GRS80

12. Coordinate Systems provide a spatial referencing system to locate points on the earth surface spherical coordinate system coordinates that describe locations on a sphere planar coordinate system coordinates that describe locations within a two dimensional Cartesian space

13. Spherical Coordinate Systems latitude and longitude parallel: lines parallel to equator meridian: lines going from pole to pole

14. Planar Coordinate Systems rectangular grid with X and Y axes X: easting Y: northing point is defined by X,Y coordinate

15. Planar Coordinate Systems Universal Transverse Mercator (UTM) units in meters transverse cylindrical projection 60 vertical zones cover globe northing in meters from equator easting in meters from false origin 500,000 meters west of zone central meridian

16. Planar Coordinate Systems Universal Transverse Mercator (UTM)

17. Planar Coordinate Systems United States State Plane Coordinate System units in feet projection in transverse Mercator or Lambert’s conformal conic tied to U.S. datum one or more zones for each state with a false origin southwest of the zone

18. Planar Coordinate Systems United States State Plane Coordinate System

19. Types of Maps Reference Map Thematic Map Qualitative Quantitative Dot Map Isarithmic Map Cartogram Proportional Symbol Choropleth Map

20. Dot Mapping

21. Isarithmic Mapping

22. Cartogram

23. Choropleth Mapping

25. Breast Cancer Incidence by County in North Carolina

26. Classification in Choropleth Mapping Constant IntervalsEqual Interval Standard Deviation Variable IntervalsQuantile Arithmetic Progression Geometric Progression Natural BreaksVisual Maximum change in slope Optimal (Jenks)

27. Classification in Choropleth Mapping

28. Thematic Map Elements Title Legend Scale Credits Mapped and unmapped areas Borders and neatline Map symbols Place names and labeling

29. Thematic Map Elements For more on choropleth mapping: http://www.personal.psu.edu/faculty/c/a/cab38/GEOG321/05_choro02/choro1_02.html