Slide 1

What are GIS Models? A simplified, manageable view of reality They capture spatial relationships of objects They capture attributes of an object Models can help us understand, describe, or predict how things work in the real world They can also help us understand our level of knowledge about the real world Slide 2 A Globe is a model of the Earth Slide 3 A Map is a graphical model of the earth surface Slide 4 A Photo is a pictorial model of surface features Slide 5 Digital Elevation Model Slide 6 A cooking recipe is a model Baking Soda Sugar Flour MIXED DOUGH Put in a OVEN At 300 F BREAD Slide 7 Models are of many different types A model could be a theory, a law, a hypothesis, an equation, or even a structured idea Common types of GIS Models: Representation Process: suitability distance surface hydrologic From Haggett and Chorley, 1967 Slide 8 What is Spatial Modeling ? The process of manipulating and analyzing spatial/geographical data to generate useful information for solving complex problems Slide 9 Why Spatial Modeling ? Finding relationships among geographic features to understand and address any particular problem Homes School Districts Streets Zip Codes Cities Counties Source: ESRI Slide 10 Systematic distortions in world fisheries catch trends Reg Watson & Daniel Pauly, Nature November 29, 2001 Catch predictions based upon: depth, primary productivity, ice cover, surface temperature, latitude, distance from shore, Upwelling index, 33 biogeochemical provinces, coastal biome Slide 11 Sequence of events In the 1970s biologists predicted that global fishery catches would start declining in the 90s. However, based upon reported catches by the different countries global catches continued to increase. It was attributed to better technology & unknown fish stocks. The Watson & Paul model implied there was a problem with the numbers of fish China was reporting. China rewarded their officials for reporting large catches which encouraged false reporting. The worlds fisheries maybe in much worse shape than expected. Slide 12 Differences between fish reported and fish predicted Slide 13 Global report catch Slide 14 Modeling Spatial Problems Are you asking the right question? Do you have the data to answer your question? Does the accuracy and resolution of the data meet the demands of your question? Do you have a good understanding of the objects in the real world that you are trying to model? Slide 15 ArcMarine Data Extraction Models to automatically extract environmental data layers for spatio-temporal analysis Model: Get-SST AML to Modeler conversion at ArcGIS 9.x From Marine Data Model Technical Workshop, 2005 ESRI UC, Halpin et al. Slide 16 Introduction to ArcGIS Slide 17 Overview of ArcGIS Increasing Functionality from ArcView to ArcInfo ArcReader is freeware. ArcGIS Extensions give added functionality to the software. Slide 18 What was a Project is now a Map Document Slide 19 ArcGIS ArcCatalog: database design and data management ArcMap map making, editing, spatial analysis ArcToolbox opens within ArcCatalog or ArcMap and it is, in essence, a huge toolbox Slide 20 The ArcMap Interface