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Geospatial Data Awareness. Overview. What is GIS? Definition Spatial Data Storage Spatial Data Analysis Spatial Data Visualization Demo: Making Non-Spatial Data Into Spatial Data Identifying or Creating a Spatial Field Cleaning up Data Geocoding and Joining Data Data Sources
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Geospatial Data Awareness Overview • What is GIS? • Definition • Spatial Data Storage • Spatial Data Analysis • Spatial Data Visualization • Demo: Making Non-Spatial Data Into Spatial Data • Identifying or Creating a Spatial Field • Cleaning up Data • Geocoding and Joining Data • Data Sources • County GIS Offices • Maryland’s GIO Office & State Agencies • Geo-spatial Data Portals • Scenario / Q & A
Information System Spatial Data Storage Query What is GIS? GIS (Geographic Information System) is a computer-based information system that can input, store, manipulate, display AND analyze geographically referenced (spatial) data. Raw Spatial Data Field Data Imagery Survey Data Etc… Information
What is GIS? Spatial Data Storage A spatial dataset consists of tabular data that is tied to a location. Raster Vector Features represented as points, lines or polygons Image made up of rows and columns of numbers
What is GIS? Spatial Data Storage The benefit of vector spatial data is that multiple fields can be tied to a single record (feature).
What is GIS? Spatial Data Storage A common format used to store spatial data is ESRI’s shapefile format. Geospatial data is often made available to the public in a shapefile format. A shapefile consists of several individual files.
What is GIS? Spatial Data Analysis Spatial Data Analysis Examples Spatial Query How many above ground storage tanks exist in Baltimore County?
What is GIS? Spatial Data Analysis Spatial Data Analysis Examples Spatial Reclassification What areas in Dorchester County are vulnerable to a 0 – 5 foot sea level rise?
What is GIS? Spatial Data Visualization Spatial Data Visualization Formats Hard Copy Maps (Small and Large Format) Digital Maps (PDF, JPEG, TIFF, etc.) Web Mapping Applications (Java Script, FLEX, etc.)
Making Your Non-Spatial Data Spatial Identifying or Creating a Spatial Field As long as your dataset has a field containing spatial data, you can map your data.
Making Your Non-Spatial Data Spatial Cleaning Up Your Data Your tabular data must be “clean” in order for it to be properly mapped. Avoid Special Characters Appropriately Formatted Fields Avoid Rare Fonts / Elaborate Table Styling Make Sure Addresses Are Correct Exclude Units in Fields Containing Measurements
Making Your Non-Spatial Data Spatial Geocoding and Joining When working with a GIS, it is important to remember there are two different types of tables one may work with: 1) Feature Attribute Table (points, lines & polygons) 2) Non-spatial Attribute Table (“flat files”) If you want to map the variations found in your non-spatial attribute table, you first need to join it to a feature attribute table using a common field or unique identifier.
Making Your Non-Spatial Data Spatial Geocoding and Joining This is a separate table (a “flat file”)
Making Your Non-Spatial Data Spatial Geocoding and Joining Georeferencing is the process ofaligning geographic data to a known coordinate system so it can be viewed, queried, and analyzed with other geographic data.
Making Your Non-Spatial Data Spatial Geocoding and Joining Demonstration Creating Spatial Data by Joining
Geospatial Data Sources Local Data If you are interested in obtaining local spatial data, the first place to check are local GIS offices.
Geospatial Data Sources State Data If you are interested in obtaining statewide spatial data for Maryland, check out these resources.
Geospatial Data Sources Federal Data If you are interested in obtaining federal-level data, the first places to check are the federal data portals. http://www.data.gov/ http://geo.data.gov/geoportal/ http://www.census.gov/geo/maps-data/ http://www.usgs.gov/pubprod/data.html#data http://www.ncdc.noaa.gov/
Geospatial Data Sources Other Geospatial Portals There are also several geospatial portals that can be used to locate various spatial datasets. http://gisinventory.net/ http://www.esri.com/data/find-data http://planet.openstreetmap.org/
Scenario / Q & A What kind of projects do you work on where spatial data is needed?
Contact Information Towson University Center for GIS Terrace Dale Building - Suite 260 Tom Earp tearp@towson.edu Jeremy Monn jmonn@towson.edu