GIS Data Sources. Thomas Talbot

Transcription

1 GIS Data Sources Thomas Talbot Chief, Environmental Health Surveillance Section Bureau of Environmental & Occupational Epidemiology New York State Department of Health

2 Outline Sources of Data Census, health, environmental, base layers Data Accuracy Data Sharing (NYS GIS Clearinghouse) GIS web services Street Address Mapping (NYS SAM)

3 US Census The US Census is mandated by the Constitution. The population is enumerated every 10 years. Results used to allocate Congressional seats, and government funding. The Census Bureau is responsible for the Census. The first census was taken in 1790, under Secretary of State Thomas Jefferson. For years between decennial census, the Census Bureau makes estimates using the American Community Survey.

4 US Census TIGER Files New York State County - 62 Minor Civil Division (Town) 1,013 Census Tract 4,902 Block Group 15,241 Census Block 350,162

5 Census Geography, Albany County

6 Census Geography, City of Albany

7 Other Census Areas Census designated places Delmar, Slingerlands, Westmere Incorporated villages Voorheesville Altamont Cities Binghamton City ZCTA Native American Reservations School Districts Congressional Districts

8 Other Features in TIGER Transportation features (CFCC Codes) Streets & highways (with street number range & name Railroads Ferry Crossings Foot paths Airports Water features (rivers, lakes, streams, ocean) Other features (landmarks, parks, malls, power lines)

9 Decennial Census Basic demographic information Age Sex Race Ethnicity Number of Housing Units Group Quarters Household relationships

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12 American Community Survey A large, continuous demographic survey 250,000 Households nationwide every month Housing unit address is the sample unit not people Produces annual and multi-year estimates of the characteristics of the population and housing

13 American Community Survey Sample of households. Census views it as producing characteristics distributions, NOT counts Produces information for small areas including tracts, block groups & population subgroups

14 American Community Survey

15 Multiple numbers for the same area Data Release Every Year Period rather than point estimates 2010 release for areas of 65,000 or more 1-year estimate (2009 collection) 3-year estimate ( collection) 5-year estimate ( collection) 2010 release for areas of 20,000 to 65,000 3-year estimate ( collection) 5-year estimate ( collection) 2010 for areas areas under 20,000 5-year estimate ONLY ( )

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23 FTP S

24 FTP Site Provides Comma Separated Value (CSV) Files Data which can imported into spreadsheet, statistical or GIS software If you want to import census attribute data to your GIS you need to assign variable names and the select which variables and geographic areas you need. The census and others have developed programs for extracting data and naming the variables.

25 Health Data Vital statistics. Birth and death (ICD Codes) Cancer Incidence Congenital Malformations Alzheimer & Dementia Registry AIDS Infectious Diseases Hospital Discharge Data (SPARCS)

26 Exposure Registries Occupational Heavy Metals Registry Childhood Blood Lead Reporting System Radon Registry Volatile Organic Compound Registry Pesticide Registry

27 Environmental Exposure Sources Toxic Release Inventory Inactive Hazardous Waste Sites Municipal landfills Discharges to water (SPDES) Household measures of radon Soil sample data Drinking water contaminants Air pollution modeled and measured Contaminants in fish Power plants Contaminants in raw and finished drinking water

28 Base Layer Data and Other Streams, Rivers, lakes, wetlands Elevation Aerial Imagery Topographic Maps Soils & geology Land use / land cover Flood zones

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30 US Census TIGER Files Topologically Integrated Geographic Encoding & Referencing Digital database developed to support Census s mapping needs. The data base defines the location and relationship of streets, rivers, railroads, and other features to each other.

31 Census Tracts Census tracts are small, statistical subdivisions of a county. Uniquely numbered in each county with a numeric code Census tracts average about 4,000 inhabitants Minimum Population 1,200 Maximum Population 8,000 31

32 Updating Census Tracts Census tracts are designed to be relatively permanent over time. Any changes are documented so data can be compared from decade to decade. Census tracts with more than 8,000 people are split into 2 or more tracts Census tracts with less than 1,200 people are merged with a neighboring tract Small boundary corrections are sometimes allowed as well. 32

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37 Census Tracts are Merged as Population Decline below 1,200

38 Data Accuracy Attribute Accuracy Spatial Accuracy Temporal Accuracy Determine level of accuracy needed for project. Examples: How many people live within an 30 minute drive to an emergency room. Who lives within 250 feet from a hazardous waste site.

39 ACS Statistical Quality Impute missing data ACS products (sample) Reported at 90-percent confidence level Summary Files also have Standard Errors May affect uses of the data Denominators Regression analysis

40 The census does not always put populations in the correct census area. Merge these blocks before using aggregation tool From 2000 census 40

41 Census Enumeration Errors 831 persons living in Colonie Shopping Center 0 persons living in neighboring apartments

42 Intercensal Estimates are Unreliable example: several disease cases have recently occurred in this area, the intercensal Claritas estimate = 0 population New construction Census Persons 2008 Intercensal Estimate 0 persons 42

43 Temporal Accuracy TIGER Streets Real Property Points

44 Spatial Accuracy Census TIGER Files (2000)

45 New York ALIS Street Files (2005)

46 Data Sharing New York Stat Clearinghouse Model

47 Geographic Databases Framework Data Additional Base Data Land Ownership Transportation Surface Waters Boundaries Geodetic Control Elevation Ortho Imagery Flood Zones Wetlands Landcover Water Lines Sewer Lines Soils 47

48 NYS GIS Data Sharing Cooperative Government, NFP, Academics Contacts Feedback 48

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54 Orthoimagery Program 4-Bands (R, G, B, and N-IR) 1-ft GSD in urban areas, +/- 4-ft 2-ft GSD in rural areas, +/- 8-ft NYC Specs 0.5-ft Color, +/- 2-ft All structures in Manhattan orthorectified Structures above 5-stories in outer boroughs orthorectified June flight for Manhattan Ground Sampling Distance (GSD) - distance between pixel centers

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56 ArcGIS Provides Access to a Number of On-line Base Maps Example : World Street Maps

57 USA Topographic Maps

58 Adding a Web Map Service (WMS) to your Map NYS GIS Clearinghouse Orthoimagery

59 Street Address Mapping(SAM) Create a statewide authoritative address point database to support next-generation and other purposes

60 SAM Big Picture Next Generation 911 requires GIS data Huge range of needs for address data statewide Building to highest level requirements (i.e. 911) will support all lower requirements Not a re-addressing project; we re just mapping what you've got Address point data will Support dispatch Be publicly available for widespread uses Support high-quality geocoding Contain no personal or sensitive information Contain unique IDs

61 61 Apartment Building Complex 70 Mc Carty Ave Building 1, Apt 1; Building 2, Apt 4; etc.

62 Homework Read: Chapter 3: Cromley & McLafferty, GIS & Public Health Mills JW, Curtis A, et al. The clearinghouse concept: a model for geospatial data centralization and dissemination in a disaster. Disasters, (3): Explore: US Census Web site: New York State GIS Clearinghouse: http//gis.ny.gov The End