Daily Archives: January 7, 2015

Integrating Political/Statistical Geography with OpenStreetMaps

OpenStreetMaps (OSM) is a collaborative project to create/maintain a free editable map of the world. The OSM Internet-based map resource is built by a community of people who contribute and maintain data about roads, local geography and much more, all over the world.

Houston, TX; Texas 113th Congressional District 29
The following view illustrates using a congressional district shapefile (blue boundary) in combination with OSM as a base layer.

GIS Applications Linking/Combining Shapefiles with OSM
This section illustrates viewing political/statistical geography in context of streets/roads shapefiles and/or Web-based street/ground coverage graphics. When using GIS tools to view census tracts (as one example) rendered through the use of shapefiles, there is often no convenient way to view the boundaries in context of roads/ground cover. There are two alternatives. One option is to add a layer using the corresponding streets/roads shapefile. This option has important features but is often difficult, time-consuming or not feasible as the roads shapefile coverages are organized in county units. Also roads shapefiles provide only part of the picture with respect to ground coverage. A second option is to use Web-based roads/ground coverage tiling services such as OpenStreetMap. Both options are reviewed here.

Georgia Metropolitan Statistical Areas shapefile overlay
Metropolitan areas are shown as brown boundaries in the following view.

The CV XE GIS software is used to view a census tracts shapefile/layer in context with 1) roads shapefile/layer and 2) Web-based OpenStreetMap (OSM) layer via OSM WMS (OGC Web Map Service). CV XE GIS supports the OGC WMS standard, which means that it can be used to open map layers from any properly functioning WMS server, including OSM WMS servers. Use of the OSM shown here is available at no cost and has global coverage. Tiling graphics are courtesy of MapQuest.

Honolulu, Hawaii with Census Tract Boundaries
The Hawaii census tracts boundaries (red) are shown in the following view.

Get Started Now
No registration or fees are required to use the CV XE GIS software with OSM. Run the CV XE GIS installer on a Windows-based computer and create views/applications such as those shown below. Make custom maps of your neighborhood or a city/country anywhere in the world.

New York City with Census Tract Boundaries
New York census tracts boundaries (red) are shown in the following view.

Atlanta, GA Region Diversity Patterns Neighborhood
Census tracts are colored based on value of the diversity index. See color patterns assigned based on diversity index values as shown in legend at left of the map. Blue tracts are most diverse; red tracts are least diverse. Tracts shown with black cross-hatched pattern are tracts with 50-percent or more Hispanic population. Transparency of the shapefile layer is set to 80% enabling the view of the OSM basemap layer.

About the Author
— Warren Glimpse, developer of the CV XE GIS software, is former senior Census Bureau statistician responsible for innovative data access and use operations. He is developer of the Columbia, MO GBF/DIME used as the prototype for the Census Bureau TIGER/Line system. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data.