By using the USGS- developed, GIS-based tool, we can automate the dasymetric mapping process. We have worked with various communities to create accurate population density maps to aid in risk and vulnerability analysis linked to natural hazards. By using the USGS- developed, GIS-based tool, we can automate the dasymetric mapping process. We have worked with various communities to create accurate population density maps to aid in risk and vulnerability analysis linked to natural hazards.
Problem: Human population distributions are commonly displayed using decennial census data. However, these data are aggregates of geographic units (census tracts or block groups) whose boundaries do not always reflect the natural distribution of human populations. A dasymetric mapping technique is one potential solution for mapping population density relative to residential land-use. Dasymetric mapping depicts quantitative areal data using boundaries that divide the area into zones of relative homogeneity with the purpose of better portraying the population distribution.
Future Work: With the automated tool, we have the ability to map and analyze any area of interest provided the appropriate data sources. We plan to update the tool to function in ArcGIS 10.
Time-Series Map of Population Distribution for Clackamas, County, Oregon: 1990-2007
Illustrated below is a time series of residential development and habitation within Clackamas County, Oregon from 1990 to 2007. Population estimates and changes to population totals over the study period are depicted by 30 meter pixels overlain on a shaded relief background generated by a 10 meter digital elevation model. High accuracy/resolution data (street address file, 0.5m ortho-imagery) from the county, combined with NLCD and Census data greatly enhanced the ability to refine the depiction of inhabited areas.
Below are publications associated with this project.
Geographic Information System Software to Remodel Population Data Using Dasymetric Mapping Methods
A New Method for Mapping Population Distribution
- Overview
By using the USGS- developed, GIS-based tool, we can automate the dasymetric mapping process. We have worked with various communities to create accurate population density maps to aid in risk and vulnerability analysis linked to natural hazards. By using the USGS- developed, GIS-based tool, we can automate the dasymetric mapping process. We have worked with various communities to create accurate population density maps to aid in risk and vulnerability analysis linked to natural hazards.
Dasymetric Map of the San Francisco Bay Area(Public domain.) Problem: Human population distributions are commonly displayed using decennial census data. However, these data are aggregates of geographic units (census tracts or block groups) whose boundaries do not always reflect the natural distribution of human populations. A dasymetric mapping technique is one potential solution for mapping population density relative to residential land-use. Dasymetric mapping depicts quantitative areal data using boundaries that divide the area into zones of relative homogeneity with the purpose of better portraying the population distribution.
Future Work: With the automated tool, we have the ability to map and analyze any area of interest provided the appropriate data sources. We plan to update the tool to function in ArcGIS 10.
Time-Series Map of Population Distribution for Clackamas, County, Oregon: 1990-2007
2000 Population Distribution(Public domain.) 1990 Population Distribution(Public domain.) Illustrated below is a time series of residential development and habitation within Clackamas County, Oregon from 1990 to 2007. Population estimates and changes to population totals over the study period are depicted by 30 meter pixels overlain on a shaded relief background generated by a 10 meter digital elevation model. High accuracy/resolution data (street address file, 0.5m ortho-imagery) from the county, combined with NLCD and Census data greatly enhanced the ability to refine the depiction of inhabited areas.
- Publications
Below are publications associated with this project.
Geographic Information System Software to Remodel Population Data Using Dasymetric Mapping Methods
The U.S. Census Bureau provides decadal demographic data collected at the household level and aggregated to larger enumeration units for anonymity purposes. Although this system is appropriate for the dissemination of large amounts of national demographic data, often the boundaries of the enumeration units do not reflect the distribution of the underlying statistical phenomena. Conventional mappinAuthorsRachel Sleeter, Michael GouldA New Method for Mapping Population Distribution
Human population counts are collected and commonly displayed uniformly across areas, such as U.S. Census Bureau block-groups and tracts. The limitation inherent in this type of representation is the assumption that people are evenly distributed across each areal unit, when in actuality many areas such as parks, open spaces, and industrial zones are uninhabited. The U.S. Geological Survey (USGS) haAuthorsRachel Sleeter