US: Using satellite images captured by Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), researchers from US Geological Survey (USGS) were able to measure Yellowstone National Park’s temperature. The geothermally active Yellowstone region, the largest in the world with 10,000 features, has been monitored for decades. In 2004, the park set out to track the park’s heat signature from three technologies: from the geothermal systems, from helicopters, airplanes and satellite imagery.
In the past, researchers had to track the temperature of features like hot pools, mud pots and fumaroles on the ground by hiking in and using probes to record the data. Now, the park can gather information more quickly across the park’s 2.2 million acres and with a variety of detail. From space, the detail is only 90 meters by 90 meters for each pixel of the image. From an airplane, the image zooms in to 1 meter by 1 meter, and from a helicopter, the detail is down to 1 foot by 1 foot, said Hank Heasler, Yellowstone’s geologist.
“The satellite imagery gives us a single snapshot of the park of what’s hot and what’s not on a particular day,” Heasler added.
Greg Vaughn, USGS researcher said that this project started a couple of years ago to see if thermal imaging from space could track significant changes over a large area and over a long time period.
Obviously, the satellite data was much easier to gather compared to hiking into each of the thousand features.
“It’s a difficult thing to do because Yellowstone is such a huge area,” Vaughn said. “It’s hard work, it’s time-consuming and there are bears.”
The key to gathering the data was only using night imagery, Vaughn added. That avoided picking up reflected heat from pavement, roofs or rocks that have been heated by the sun. Winter nights are the best, because then the park’s thermal features show up markedly better compared to the snow-covered and frozen surroundings.
Since Yellowstone has seen significant volcanic activity in the past — including an eruption that created the vast Yellowstone caldera — scientists at the Yellowstone Volcano Observatory in Utah are interested in monitoring the thermal features’ vital signs.
“This technology and data could be applied to any geothermal and volcanic areas around the world to monitor eruptions and maybe even predict volcanic activity,” Vaughn said. “Most volcanoes aren’t monitored until they erupt, and I want to get ahead of that.”
Source: Billings Gazette