1 / 55

Geospatial Data

Geospatial Data. Michele Shular Geosciences Librarian mshular@buffalo.edu. UB Libraries GIS Services Where we are now…. One Public Access GIS Workstation Science & Engineering Library ESRI ArcGIS 9.0, ArcView 3.3 & Network Analyst Patron Assistance Locating and Retrieving Data

tomai
Télécharger la présentation

Geospatial Data

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Geospatial Data Michele Shular Geosciences Librarian mshular@buffalo.edu

  2. UB Libraries GIS Services Where we are now… • One Public Access GIS Workstation • Science & Engineering Library • ESRI ArcGIS 9.0, ArcView 3.3 & Network Analyst • Patron Assistance • Locating and Retrieving Data • Using Data & Software Help • ESRI Virtual Campus Courses

  3. ESRI Virtual Campus Courses • Free to UB faculty, staff, students • 50+ courses and workshops • Registration form online • 15-25 hours per course • All needed data provided • Certificate for course completion • http://ublib.buffalo.edu/libraries/asl/gis/GIS-training.html

  4. 12 Factors in Choosing Geospatial Data • Source • Coverage & Extent • Time Period • Scale • Positional Accuracy • Attribute Availability

  5. Originating Sources of Geospatial Data • Government • Local • Regional • State • Federal • International • Utilities • Universities & Research Centers • Commercial • usually originate from govt. sources, but are value added

  6. 12 Factors in Choosing Geospatial Data • Source • Coverage & Extent • Time Period • Scale • Positional Accuracy • Attribute Availability

  7. Coverage & Extent

  8. 12 Factors in Choosing Geospatial Data • Source • Coverage & Extent • Time Period • Scale • Positional Accuracy • Attribute Availability

  9. Time Series

  10. 12 Factors in Choosing Geospatial Data • Source • Coverage & Extent • Time Period • Scale • Positional Accuracy • Attribute Availability

  11. Scale • Ratio of map units to real world units • Choose scale inversely proportional to extent • Standard Scales: • 1:12,000 • 1:24,000 • 1:100,000 • 1:250,000 • 1:1,000,000, etc. LARGE SMALL

  12. 12 Factors in Choosing Geospatial Data • Source • Coverage & Extent • Time Period • Scale • Positional Accuracy • Attribute Availability

  13. Positional Accuracy Tiger Streets (federal) DOT Streets (state) County Streets (local)

  14. 12 Factors in Choosing Geospatial Data • Source • Coverage & Extent • Time Period • Scale • Positional Accuracy • Attribute Availability

  15. Attribute Availability

  16. 12 Factors in Choosing Geospatial Data cont’d • File Size • File Format • Projection & Datum • Tiling Scheme • Metadata Availability • Use Restrictions & Access

  17. File Size: Feature Subset Wessex Streets 5.0 TIGER Data .shp file: 4.67 mb ESRI Major Roads TIGER Subset .shp file: 0.22 mb

  18. 12 Factors in Choosing Geospatial Data cont’d • File Size • File Format • Projection & Datum • Tiling Scheme • Metadata Availability • Use Restrictions & Access

  19. Formats BIP MrSID Orthophotos TIFF BMP JPEG

  20. 12 Factors in Choosing Geospatial Data cont’d • File Size • File Format • Projection & Datum • Tiling Scheme • Metadata Availability • Use Restrictions & Access

  21. Common NYS Projections State Plane NAD83 Geographic Coordinates State Plane NAD27 UTM Zones 17 & 18

  22. 12 Factors in Choosing Geospatial Data cont’d • File Size • File Format • Projection & Datum • Tiling Scheme • Metadata Availability • Use Restrictions & Access

  23. Common TilingSchemes • Counties (soils) • Sub-county (digital orthophotos) • USGS Quad (1:12k, 1:24k, 1:100k, 1:250k) • River Basin or Sub-basin (streams) • State

  24. Tiling Issues • Small Tiles • need to merge data sets: time consuming, possible software limits • Large Tiles • need to clip data sets: time consuming, possible software limits • Incongruous Tiles • Counties and River Basins • need to both merge and clip data

  25. 12 Factors in Choosing Geospatial Data cont’d • File Size • File Format • Projection & Datum • Tiling Scheme • Metadata Availability • Use Restrictions & Access

  26. Metadata Availability • Federal data is required by U.S. law to be accompanied by FGDC compliant metadata • State, Local and Commercial data producers are not required, and therefore, many do not • Some data producers may provide metadata for a dataset, but not for individual layers

  27. 12 Factors in Choosing Geospatial Data cont’d • File Size • File Format • Projection & Datum • Tiling Scheme • Metadata Availability • Use Restrictions & Access

  28. Data Use Restrictions & Access • Federally produced unclassified data is in the public-domain. • State, local, and commercial data are generally under distribution agreements that limit their use for educational purposes only. • Distribution of data for “un-seeable” features (underground infrastructure) is being stopped for homeland security.

  29. GIS Data Types • Feature Data • Digital Imagery & Photography • Tabular data

  30. USGS Datasets • Digital Raster Graphic (DRG) • Digital Line Graph (DLG) • National Hydrography Dataset (NHD) • National Land Cover Dataset (NLCD) • Digital Orthophoto Quadrangle (DOQ) • Digital Elevation Model (DEM) • National Elevation Dataset (NED) • Geographic Names Information System (GNIS)

  31. Digital Raster Graphic (DRGs)

  32. Digital Line Graph (DLGs)

  33. DLGs Nine Categories of Attributes • Public Land • Boundaries • Transportation • Hydrography • Hypsography (elevation) • Non-vegetative Features • Survey Control and Markers • Manmade Features • Vegetative Surface Cover

  34. National Hydrography Dataset (NHDs)

  35. Digital Orthophoto Quadrangles (DOQs)

  36. Digital Elevation Model (DEMs)

  37. National Elevation Dataset (NEDs)

  38. National Elevation Dataset (NEDs)

  39. National Land Cover Dataset (NLCDs)

  40. National Land Cover Dataset (NLCDs)

  41. NLCD Legend

  42. More Federal Types… • FEMA: flood zones • NOAA: coastal data • EPA: environmental data • NRCS: soil surveys, agricultural data • FWS: Natl. Wetlands Inventory (NWI), wildlife • NPS: recreational, historic data • USDA: forest, agriculture, natural resources

  43. Tabular Census Data • Population Census • Economic Census • Agricultural Census • State Data Centers

  44. CensusPopulation Data • Year 2000 latest complete data • Varied geographies to census blocks • Population, race/ethnicity, income, housing, family structure, employment, education, etc. • SF1 = short form, 100% count • SF3 = long form, about 17% count, more attributes • Join tabular data to Census geography shapefiles • UB Libraries Census Resources Information Guide • http://ublib.buffalo.edu/libraries/asl/guides/busdoc/census.html

  45. Census Data Resources Online • Generate tables from American Factfinder • http://factfinder.census.gov/ • Be sure to get a geographic ID field to join your tables to the shapefiles. Download TIGER shapefiles from ESRI • http://www.esri.com/data/download/census2000_tigerline/index.html • Some basic tables can be downloaded here too

  46. Internet Mapping Services (IMS) • Interact with GIS data via Web browser • GIS access for those without: • Expensive GIS software • GIS-capable computer equipment • GIS expertise • High networkbandwidth • Data storage space

  47. Erie County Internet Mappinghttp://erie-gis.co.erie.ny.us/website/erie_help/help.htm

  48. Local Data – Typical Layers • Cadastral (tax parcels) • Digital Orthophotos • Street centerlines • Topographic contours • School, sheriff, fire, EMS districts • Voting precincts • Miscellaneous cultural and infrastructure

  49. CUGIR Cornell Univ Geospatial Information Repository • http://cugir.mannlib.cornell.edu/ • Adirondack Park Agency • Cornell Department of Natural Resources • National Atlas • NYS Dpt of Agriculture and Markets • NYS Dpt of Environmental Conservation • Tompkins County ITS/GIS • US Census Bureau • US Geological Survey • USDA Natural Resources • Conservation Service

  50. GNIS Database - USGS • Geographic Names Information System • http://geonames.usgs.gov/redirect.html Can query: • State • County • Feature Class • Topo Map Name

More Related