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“3-D” & Temporal GIS. Horizontal sure, but …. . how to deal with elevation/depth or time Vertical Horizontal and vertical Horizontal, vertical, and time. ArcScene 9 Demo. http://dusk.geo.orst.edu/gis/captivate_arcscene/arcscene_demo.htm. The Vertical Dimension. - PowerPoint PPT Presentation
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“3-D” & Temporal GIS
Horizontal sure, but ….
how to deal with elevation/depth or time
VerticalHorizontal and verticalHorizontal, vertical, and time
ArcScene 9 Demo
http://dusk.geo.orst.edu/gis/captivate_arcscene/arcscene_demo.htm
The Vertical Dimensiontwo very different ways of looking at representations of the vertical dimension (third dimension) in GIS“2.5-D” and “3-D”vertical dimension combined with temporal query = “4-D”
“2.5 D”most common way of “doing 3D” in commercial GIS packagesz value (normally elevation) is recorded as an attribute for each data point (x,y)z values can be used in a perspective plot to create the appearance of 3 dimensionsnot true 3-D representation because elevation is not encoded in data structure, not in topology
2.5 D Representationsattractive displays of topography and other continuous surfaces from DEMs or TINsperspective plots computed from any viewpointadditional layers "draped" over the surface
“Coastal Terrain Model”USGS Topography
+ =
Integrated Topo-Bathy Model
BathymetryTopography
…a surface that integrates topography and bathymetry
Satellite ImageryDraped on Topo-bathy model
Boundary RepresentationTIN is a 2.5 D type of B-rep
one value of z for every x,y each object has faces, edges, points
Perspective Plot from TIN (2.5-D B-Rep)
B-Rep of a Cave Passage
True 3-Dstore data in structures that actually reference locations in 3D space (x,y,z)here z is not an attribute but an element of the location of the point if z is missing, object does not exist!several z’s possible for a single x-y pair,
soundings in the ocean or atmosphere, geologic logs of wells
3-D Applicationsgeological/geophysical exploration engineering design of mines, quarries, dams, reservoirs, etc.scientific explanation of 3D processes such as ocean currents or lava flows
“data driven” - may not necessarily know what you will find in 3Dso the structure of the representation may enhance types of analyses that can be performed
Fonseca, Mayer, and Paton in Wright (ed.) Undersea with GIS published by ESRI Press
Fonseca, Mayer, and Paton in Wright (ed.) Undersea with GIS published by ESRI Press
“Fledermaus”Interactive Visualization Systemswww.ivs3d.comhttp://dusk.geo.orst.edu/gis/captivate_ivs/ivs1.htm
http://dusk.geo.orst.edu/gis/captivate_ivs/ivs2.htm
http://dusk.geo.orst.edu/gis/captivate_ivs/ivs3.htm
Volumesvisualization of volumesmodeling of volumes
algorithms for 3D spatial analysis simpler, more efficient, if data in a volumetric form
Example two: Hydrothermal Plume model output
VTK/Java3D allows volumecalculations,rendering, and analysis.
● 3D probe● animation● bathymetry
● multibeam● Smith/Sandwell
Vance et al., NOAA Alaska Fisheries Science Center
Underwater Behavior of Humpback Whales: Potential Entanglement in Fishing Gear
Stellwagen Bank National Marine Sanctuary - Ware et al., Center for Coastal and Ocean Mapping, U. of New Hampshire
Spatial Occupancy Enumeration(SOE)
volume is divided into cubes or voxelsusually produced by converting from B-reps (similar to converting vectors to rasters in 2D)mass, volume and surface area are quickly computed as Boolean operations [on (full) / off (empty)] or voxel counts
SOE of a Mine/Quarry
Surface Water Runoff
Gold, Transactions in GIS, 2006
Commercially Available?Research frontiernot too many truly 3D GIS packages on the market2- or 2.5D GIS linked to 3D modeling package
You knew I had to mention it…GOOGLE EARTH
Sketch Ups and Touch TablesInsert your own objects
Google Ocean“Visualize” with your hands
http://www.youtube.com/watch?v=X2pPeW4cUgU&feature=PlayList&p=FB02B6AD35983A48&playnext=1&index=14http://www.youtube.com/watch?v=W3dz2xpCJVU&feature=related
Time Dependencetime dependence adds a third dimension to spatial data, just as the vertical dimension doesor may be added to 3 spatial dimensions to give 4D
Coastal Evolution of OR/WA
Cross & Twichell, USGS Woods Hole in Wright (ed.) Undersea with GIS, ESRI Press, 2002.
Time and Geographical Datacomputer science has dealt with time dependence of records in databases
e.g., records may be valid only for limited times geographical cases are more complex -
objects may have limited existence, but may also move, change shape, and change attributes
database models for time? few “temporal GISs” on the market
Tracking Analyst for ArcGIS
Dealing with Time in GISshape of objects same, but attributes changesame shape, same attributes, but boundaries between objects or locations of objects change
Turn on/off or moveshapes of objects change through time
define a limited number of time "slices"