Geographic Information Systems SGO 1910 4930 November 8

Geographic Information Systems SGO 1910, 4930 November 8, 2005

Announcements n n e. Seminar in GIS: Putting the e into GI Science (Mark Birkin, Leeds). Thursday, November 17, room 3514 Georg Sverdups Hus. Norsk ESRI brukerkonferanse 2006 Den 17. norske ESRI brukerkonferansen går av stabelen 1. -3. februar 2006. Konferansen byr på en rekke foredrag, tekniske minikurs, bransjeseminar og sosiale aktiviteter. Vi ser frem til spennende dager sammen med deg! Påmelding og mer informasjon kommer senere.

Announcements Extended access to GIS lab during Nov. Dec? n GIS Internships: Any interest? n

Oslo Project Groups 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Marita Sanni, Kristin I. Dankel, Solveig Melå + Svein Johan Hansen? Åslaug Enger Olsen, Maria Lyngstad, Guro Bakke Håndlykken og Jorunn Randby (4) Nina Ambro Knutsen, Ellen Winje og Leif Ingholm, Gjermund Steinskog (4) Birte Mobraaten, Hans Petter Wiken, Silje Hernes and Bente Lise Stubberud (4) Daniel Molin, Ida Sjølander, Anne-Lise Folland Nicolai Steineger (4) Hæge Skjæveland, Marie Aaberge, Cecilie Hirsch, Kaja Korsnes Kristensen (4) Urs Dippon, Steven huiching Yip, Harald Kvifte & Eirik Waag (4) Marthe Stiansen, Marielle Stigum, Tomas Nesset, Andreas Skjetne (4) Andreas Dyken, Håkon Grevbo, Terje-Andre Gudmundsen, Øystein Kristiansen (4) Andreas Wilhelm Westgaard, Grete Simensen og Ingvild Jøranli, Solveig Lyby (4) Linda Markham, Marte Hunsdal Knutsen, Anette Nesvold, Berit Indset (4) Magnus Campbell, Johannes Devik Brekke, Espen Fait, Mathias Ødegård (4) Julie Aaraas, Tonje Einarsen, Anne Marie Skancke, Bård Bergland (4)

Making Maps With GIS

Introduction Output is the pinnacle of GIS projects n Two main types of output n – Maps – Visualizations (see chapter 13) n Maps are good at summarizing and communicating

What is a map? n “A graphic depiction of all or part of a geographic realm in which the real-world features have been replaced by symbols in their correct spatial location at a reduced scale. ” power line

Map function in GIS Storage n Temporary communication n Intermediate check of data n Final report n

GIS Processing Transformations

Characteristics of Map n Two main types – Topographic – Thematic n Some map problems – Can miscommunicate – Each map is just one of all possible maps – Complex maps can be difficult to understand

Topographic Map

Thematic Map

Map Types Point data n Line data n Area data n Volume data n Time data n

Choosing a Map Type Cartographers have designed hundreds of map types: methods of cartographic representation. n Not all GISs allow all types. n Most have a set of basic types n Depends heavily on the dimension of the data to be shown in the map figure. n

Choosing the Wrong Type Fairly common GIS error. n Due to lack of knowledge about cartographic options. n Can still have perfect symbolization. n Possibility of misinformation n Definite reduction in communication effectiveness. n

Choropleth Class Schemes

Choosing Types n n n Check the data – Continuous – Discrete – Accuracy & Precision – Reliability Dimension (Point, Line, Area, Volume) Scale of Measurement (Nominal, ordinal, etc. ) GIS capability Is there a need to supplement GIS software? (e. g. with a drawing package)

Maps and Cartography Map – ‘digital or analog output from a GIS showing information using well established cartographic conventions’ n Cartography is the art, science and techniques of making maps n

The Need for Design To appear professional and avoid errors, GIS maps should reflect cartographic knowledge about map design. n A map has a visual grammar or structure that must be understood and used if the best map design is desired. n Cartographic conventions should be followed (e. g. forests should be green). n

Map Design Good map design requires that map elements be placed in a balanced arrangement within the neat line. n A GIS map is designed in a process called the design loop. n

To be effective, a map must be correctly designed and constructed.

The Parts of a Map: Map Elements Border Neat line Title The United States of America Figure Legend Ground Alaska 0 1 2 3 4 Hawaii 0 4 Inset Scale Washington, D. C. National Capital hundreds of kilometers 04 Place name Lambert Conformal Conic Projection Source: U. S. Dept. of State North Arrow Credits

Inset map Scale Author North Arrow Data Source Map Body Projection Title Grid Legend

Bertin's Graphic Primitives

Visual balance is key! Visual balance is affected by: v the "weight" of the symbols v the visual hierarchy of the symbols and elements v the location of the elements with respect to each other and the visual center of the map. n

Visual center 5% of height Landscape Portrait

Visual Layout Title Here Eye expects (1) balance and (2) alignment

Text: Selection and Placement POINT LINE e d u M La k Oslo BM 232 Bærum 20 0 Kristiansand R S U 6 6 e t u o AREA Some cartographic label placement conventions. Points: right and above preferred with no overlap. Lines: Following the direction of the line, curved if a river. Areas: On a gently curved line following the shape of the figure and upright.

Text placement Trondheim Path right Trondheim Bogstadvann P a t h D o w n

Symbol “weight” Line weight Pattern Shading Hue

Map Design and GIS When a GIS map is the result of a complex analytical or modeling process, good design is essential for understanding. n The map is what distinguishes GIS as a different approach to the management of information, so extra care should be taken to improve the final maps that a GIS generates in a GIS task. n

Limitations of Paper Maps Fixed scale n Fixed extent n Static view n Flat and hence limited for 3 D visualization n Only presents ‘complete’ world view n Map producer-centric n

Conclusions Cartography is both an art and a science n Maps are fundamental to GIS projects n Modern advances in cartography make it easy to produce good and bad maps n New technology and especially the Internet has change the content and techniques of GIS-based cartography n

Multivariate Mapping