Geographical Information System GIS LOOM.02.331 anto.aasa@ut.ee
Scale GIS and spatial planning National Regional Local Strategic (National Dev. Plan) National Goals and development policy Tactical (Regional guidelines Spatial Strategy) Articulation of Strategies Level of Detail Implementation (Development Plans) Land use, Housing, Roads Time Horizon After Keane, M et al & Lee DB
GIS functions Mapping and visualization; administration of geographical information; data collecting and updating; geographical analysis.
GIS in spatial planning GIS as databases Planning Decision Support systems Public Participation and Information Access Modelling & Simulation Activities
Geographic information system (GIS) Mutually related complex of software and data Watching geographical information, Administration of geographical information, Analysis of spatial relationships and patterns, Modelling of spatial processes.
GIS Hardware Software Database Geographical space Theme (attributes) Operations Human resource
History First person who placed different layers on top of each other?
Cholera deaths in London John Snow 1854
History 1963: first nation-wide GIS - Canada 1966: first raster-gis 1972: first civil use remote sensing satellite Landsat 1 1978: first satellites of NAVSTAR (development of GPS technology) 1979: first vector-gis ODYSSEY GIS 1981: Esri ARC/INFO 1986: MapInfo first desktop GIS 1994: beginning of standardization of spatial data and infrastructure (OpenGIS consortium) 1996: first Internet based GIS products 1996: first Internet based map service MapQuest 2000: over 1 million professional GIS users in world, over 5 million average GIS users Today: everyone can GIS
Area of use Land survey, cartography Logistics Aviation Real estate Military forces Trade Local authority Science Infrastructure management Spatial planning
Important factors for spatial analysis Location data Attribute data GIS 12
Spatial databases & GIS Location: spatial vs descriptive? N 48 21 17 E 11 47 15 Germany, Munich airport Relation between objects Distances Patterns 13
Location: Descriptive Spatial Network
Everything, what happens in real world has geographical coordinates X Y Z time (also in virtual space)
Location Map and database must be in same projection and datum Datum model of the earth Projection curved surface to flat plane 16
Earth is not ideal sphere but geoid (potatoshaped) Earth model: ellipsoid Map projection method of representing the surface of Earth on a plane All map projections distort the surface in some fashion Error minimization
Distortions http://blog.perrygeo.net/2005/12/11/tissot-indicatrix-examining-the-distortion-of-2d-maps/ area, direction, scale, distance. 19
Representation of spatial data Real world is too complex Simplified models Maps Cartography http://www.colorado.edu/geography/gcraft/notes/datum/datum_f.html
Modelling the real world Discrete objects Continuous fields Visualization of invisible objects / phenomenas (Augmented, Mixed Reality)
Model accuracy Augmented reality
Point Vector Line Polygon Shp-layer:
Representation of geoinformation in GIS objects points, lines, polygons; raster; attributes.
Raster ortophoto Landuse concentration Lat Lon Value 26.466 58.478 165 slope Elevation shading Population density
Vector layer Attributes table: Rows: map objects Columns: attributes Queries (SQL)
Layer based model: One theme for every layer One data type for every layer (point, line, polygon, raster) Elevation
Perception Use of color Traditions of visualising certain object types orientation Symbols Colors
Perception
Map (data) scale the ratio of a distance on the map to the corresponding distance on the ground (e.g. 1:400 000) Generalization Simplifying of objects Measurements accuracy Model accuracy Amount of data
Generalization
GIS output Table Graph Report Thematic map Something else? What is the aim?
Internet maps Geoportal of Estonian Landboard Open Street Map Google Map Here Map
Creating GIS Reality model (description of the real world) Data model (database structure and technology) Representation model (rules for data representation) e.g. Roads on top of rivers
Management of spatial data Raster model Rectangular regular grid of pixels Vector model Points, lines, polygons (functions determining the shape and form of objects)
Processing of geographical data Processing of the initial data for achievement of goals Queries (response to relevant conditions) Spatial analysis (description of place, attribues and relationships between them)
Quality of spatial data Completeness (missing, redundant data) Consistence Location correctness Up-to-date Thematic correctness
Seminar 1 Simple thematic maps in: Q-GIS (Quantum GIS) http://www.qgis.org/en/site/ R & RStudio http://www.r-project.org/ https://www.rstudio.com/