Landsat Over Wyoming: A New Yellowstone Hot Spot, Burn Maps and Changing Sagebrush

Landsat satellites have imaged Earth’s land surface for 50 years — the world’s longest continuous record of it. In Wyoming, their data help scientists find new geothermal activity, map wildfire damage and track slow changes in the landscape.

A new thermal area in Yellowstone

Yellowstone National Park, established in 1872 in northwestern Wyoming, sits in an area of several historically large volcanic eruptions. Magma lies close to the surface, heating underground water and creating more than 10,000 geothermal features, such as hot springs and geysers. Thermal areas — ground altered by hot water or holding hydrothermal minerals, usually with little vegetation — can warm up or cool down over time.

Landsat 8’s Thermal Infrared Sensor (TIRS) measures surface temperature and maps these areas. In a nighttime Landsat 8 image from April 20, 2017, USGS and National Park Service researchers discovered a new thermal area.

The new thermal area (white pixels show warmth) between the Tern Lake Thermal Area and West Tern Lake, April 20, 2017. Image: U.S. Geological Survey.

Mapping how badly land burned

In 1988, a series of 51 wildfires burned more than a third of Yellowstone — nearly 800,000 acres. Most were started by lightning and worsened by built-up fuel and an unusually dry July. They burned at different intensities, leaving a mosaic of burned and unburned land.

The Landsat-based Monitoring Trends in Burn Severity (MTBS) program maps the severity and extent of large U.S. fires from 1984 to the present — nearly 29,000 fires so far — informing fire management, land management and research on recovery.

MTBS map of the 1988 Clover Mist Fire. Map: U.S. Geological Survey and USDA Forest Service.

Tracking change in sagebrush

Landsat underpins many tools that monitor how land cover changes. In one USGS study of a southwestern Wyoming sagebrush ecosystem, scientists used 32 years of Landsat data to measure how much shrublands changed, how variable they were, and how temperature and precipitation drove the changes — information that can help anticipate the effects of climate change.

Pronghorn foraging in sagebrush near Split Rock, Wyoming. Photo: Jennifer Strickland, U.S. Fish and Wildlife Service.

Landsat for the nation

The USGS National Land Imaging Program supplies satellite imagery and other remote sensing data to government, business, universities and the public, with worldwide access to Landsat data through the USGS Earth Resources Observation and Science (EROS) Center.

• Landsat is the most widely used land remote sensing source in federal civilian agencies, and local, state and Tribal agencies rely on it too — for decisions on land, water and resources that protect life and property, safeguard the environment and support climate resilience.
• Businesses use it for logistics, resource allocation and investment decisions; commercial imaging firms build new services on it.
• A 2017 USGS study put Landsat’s annual economic benefit to the United States at $2.06 billion, far more than it costs to build and run.

Landsat 8 and Landsat 9 together cover Earth’s land every 8 days. NASA and USGS are designing the follow-on mission, Landsat Next, to extend the record.

Sources

Based on "Wyoming and Landsat," U.S. Geological Survey Fact Sheet 2022–3027; a work of the United States government in the public domain. Images from the same fact sheet.