This data layer is an element of the Oregon GIS Framework. The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) Database (MTDB). The MTDB represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation.

Census tracts are small, relatively permanent statistical subdivisions of a county or equivalent entity, and were defined by local participants as part of the 2020 Census Participant Statistical Areas Program. The Census Bureau delineated the census tracts in situations where no local participant existed or where all the potential participants declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of census data and comparison back to previous decennial censuses. Census tracts generally have a population size between 1,200 and 8,000 people, with an optimum size of 4,000 people. When first delineated, census tracts were designed to be homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Physical changes in street patterns caused by highway construction, new development, and so forth, may require boundary revisions. In addition, census tracts occasionally are split due to population growth, or combined as a result of substantial population decline. Census tract boundaries generally follow visible and identifiable features. They may follow legal boundaries such as minor civil division (MCD) or incorporated place boundaries in some States and situations to allow for census tract-to-governmental unit relationships where the governmental boundaries tend to remain unchanged between censuses. State and county boundaries always are census tract boundaries in the standard census geographic hierarchy. In a few rare instances, a census tract may consist of noncontiguous areas. These noncontiguous areas may occur where the census tracts are coextensive with all or parts of legal entities that are themselves noncontiguous. For the 2010 Census and beyond, the census tract code range of 9400 through 9499 was enforced for census tracts that include a majority American Indian population according to Census 2000 data and/or their area was primarily covered by federally recognized American Indian reservations and/or off-reservation trust lands; the code range 9800 through 9899 was enforced for those census tracts that contained little or no population and represented a relatively large special land use area such as a National Park, military installation, or a business/industrial park; and the code range 9900 through 9998 was enforced for those census tracts that contained only water area, no land area.

Urban Heat Island images:MorningAfternoonEveningTacoma Heat Island StudyData collected on 7/25/2018, collected by Dr. Vivek Shandas, Capa StrategiesWhat Earth Economics is working on:Through grant funding, Earth Economics is working on building out an approach and methodology using Urban Heat Island modeling (LANDSAT data) to assume health impacts (mortality rates) on a census tract level, using research on how demographics and UHI impact community health outcomes.Variables:Name: Census Block Group NamePop: Census Block Group populationIncome: Average individual Census Block Group level annual incomeOver 65: Population over age 65Under14: Population under age 14AF: Afternoon temperature (C), averaged to Census Block Group (July 25, 2018). Data collected by Dr. Vivek Shandas using this methodologyPm: Evening temperature (C), averaged to Census Block Group (July 25, 2018)Combtemp: Average of evening and afternoon temperatureHighRiskAgeGroup: Percent of population in a high risk age group for heat related illness (over age 65 and under age 14)Density: Population DensityCity of Tacoma Contact: Vanessa Simpson, Senior Technical GIS Analyst, Environmental Servicesvsimpson@cityoftacoma.org

PARD’s Long Range Plan for Land, Facilities and Programs, Our Parks, Our Future (adopted November 2019) compared Austin’s park system to five peer cities: Atlanta, GA, Dallas, TX, Portland, OR, San Antonio, TX, and San Diego, CA. The peer cities were selected based on characteristics such as population, size, density, and governance type. Portland and San Diego were selected as aspirational cities known for their park systems.

Note that the table below presents each scoring area’s 1 to 100 index, where 100 is the highest possible score.

A dataset listing Maine cities by population for 2024.