This shapefile contains polygon boundaries for thermal areas within Yellowstone National Park (YNP).

The original 1996 coverage, "Thermal Areas of Yellowstone National Park, WY", was used as a base for this shapefile. Using one-meter DOQQs, field observations, historical data, and data from the RCN Thermal Inventory Project, the original boundaries were refined, sub-divided, and attributed. Attributes included general park location, basin or area division and names, group and/or complex division and names, division of areas based on pH grouping of inventoried thermal features within thermal areas. The shapefile was originally created for use by park personnel for resource monitoring and protection.

In 2008 these data were provided to the USGS Yellowstone Volcano Observatory for use in a new thermal monitoring project employing satellite-based thermal infrared remote sensing images to assess and update these thermal area polygons. The data released here are a result of that work and published in the USGS Scientific Investigations Report “Provisional Maps of Thermal Areas in Yellowstone National Park, based on Satellite Thermal Infrared Imaging and Field Observations.” As this is a work in progress, there will be future updates to these data.