First Exam: New Date. 6 Geographers Tools Maps and their Parts 9/14/2017 MAP MAKING MAP MAKING MAP PROJECTIONS MAP PROJECTIONS

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1 6 Geographers Tools Maps and their Parts Prof. nthony Grande Hunter ollege Geography Lecture design, content and presentation FG Individual images and illustrations may be subject to prior copyright. First Exam: ew ate THURSY, September 28, ombination of multiple choice questions and map interpretation. ring a #2 pencil with eraser. ased on class lectures supplementing chapter 1. Review lecture slides. If you miss the exam, an essay style make up exam will be given. 2 MP MKIG PROLEM: How do we transfer information about the 3- Planet Earth onto a smaller 2- object without distorting that information? The mapmaker must deal with 3 obstacles: 1. onversion of a sphere (curved surface) to a plane (flat surface). 2. Shrinking of the earth s surface to fit the smaller object. 3. Portrayal of information to make it understandable. MP MKIG The mapmaker deals with them by using: 1. PROJETIO to convert a sphere to a flat surface. 2. SLE to shrink the earth s surface proportionally to fit the object. 3. SYMOLIZTIO to portray information and make it understandable. 3 4 MP PROJETIOS Only a globe can portray the earth s surface without distortion. Only a globe can show true shape true relative area true distance true direction ny flat map will sacrifice 1 or 2 or 3 or all 4 advantages of a globe. map cannot show more than three advantages at any one time! MP PROJETIOS map projection is a representation of the 3- earth s grid on a flat surface. Each of these projections has a combination of unique characteristics to show shape, relative area, distance and direction. If you have a thematic atlas read the section on maps and map projections

2 MP PROJETIOS Geometrical Map Projections The basic concept behind a map projection is having a light source within the globe and having that light source project the earth s grid on to a flat object. However, most currently used map projections are mathematically derived and cannot be projected. 1 min intro to map projections ylindrical onical Planar If the globe is wrapped in a cylinder, a cylindrical projection is created. cone creates a conical projection. plane (flat sheet) creates a planar projection. 7 8 Map istortion YLIRIL PROJETIO ll maps distort shape in some way. OTE: In the illustrations the circles and shape-ofhead diagrams are used to show distortion. In this projection the lines of longitude are parallel! annot show the polar regions. Star illustrates areas of distortion. otice the unusual scale on the map OIL PROJETIO In this projection the lines of longitude are too close at the poles. Lines of longitude are too far apart at the equator. Least distortion in the mid-latitudes PLR PROJETIO In this projection a plane (flat sheet) is placed tangent to the globe. Used mainly for polar areas. Least distortion in the center of the map but perimeter areas are stretched

3 Goode s Homolosine Projection Other Interrupted Projections Peeled globe designs mathematically derived projection providing the illusion of a peeled orange. Its classification is interrupted projection min video map proj 14 SLE Scale is a RTIO. It is the relationship between distance on the map and the equivalent distance on the earth s surface (map to earth). Scale is a means of measurement. Scale influences detail (symbolization). There are 3 ways to show scale. Showing Scale a) VERL/Written: in words b) GRPHI/ar: as a line or bar c) FRTIO/Ratio: as a mathematical equation Scale can be designated large or small. Large scale: Shows greater detail but less of an area. Small scale: SLE Shows greater area but in less detail. ( globe is a small scale map.) Small Scale vs. Large Scale Small scale Large area, little detail Large scale Small area, great detail 17 3

4 Effect of Scale on ETIL Same size squares but each square shows different total surface area and different detail. ote that each shaded box (a, b, c, d) fits into the next one. Map SYMOLIZTIO Symbolization is the portrayal of information. Ideal maps should have the following seven elements: 1. Title 2. ate 3. Grid 4. irection 5. Scale 6. Projection used 7. Legend or key Maps and Symbolization Map Symbols The Legend or Key 21 The reader must know what the shapes, colors, patterns and sizes mean. Therefore a LEGE or KEY is needed. Without it, what is presented are just meaningless shapes and colors. STRIZTIO of SYMOLS Standardization makes it easier to read and interpret maps. USGS topographic maps use standardized colors, symbols and overlays to indicate features of the physical and cultural landscapes. IRETIO Every map needs to have an indication of major compass points: north, south, east and west. This can be done with a compass arrow, marking of lines of latitude and longitude and/or indication of quadrant. Where is north on this map?

5 Southern Hemisphere Which way is north? y following the meridians of longitude away from the South Pole, you will eventually end at the orth Pole. + South Pole Which arrow points orth? E F West This way is orth!! orth Pole E East F World Map What is wrong with this map? Must always follow lines of latitude and longitude to ascertain direction. Pacific Ocean entered World Map World Map E X T What is wrong with this map? TYPES of MPS World Map entered on ustralia