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Scientific explorers

Camp of the Hayden Geological Survey of 1871 along Yellowstone Lake. 

William H. Jackson, USGS

Yellowstone Caldera Chronicles is a weekly column written by scientists and collaborators of the Yellowstone Volcano Observatory. This week's contribution is from Behnaz Hosseini, geologist, and Jefferson Hungerford, park geologist, at the Yellowstone Center for Resources in Yellowstone National Park.

In the early 19th century, European settlers began exploring the lands of northwestern Wyoming — lands that had been known to Native Americans for millennia. The first organized expedition to the Yellowstone region was in 1869, and it laid the groundwork for the following Washburn-Langford-Doane Expedition of 1870 and Hayden Geological Survey of 1871. The two latter expeditions documented the dynamic and diverse hydrothermal features and played a pivotal role in convincing the U.S. Congress to pass legislation establishing Yellowstone National Park in 1872. With this, America's greatest idea came to fruition.

For more than a decade after its founding, Yellowstone's succession of superintendents struggled to protect the park's natural features without adequate laws or resources. Congress did not allocate funds for an effective administration, and so in 1886 the Secretary of the Interior summoned the U.S. Army to take charge of Yellowstone. Three decades later, the Organic Act of 1916 established the National Park Service, giving Yellowstone the centralized administration required to protect park resources and provide educational experiences for visitors.

Of the eight Yellowstone Volcano Observatory member agencies, the NPS is the "boots on the ground" presence in Yellowstone. As was mentioned in an earlier Yellowstone Caldera Chronicles column, it may be tempting to imagine a legion of scientists stationed at several lookouts over the Yellowstone Caldera. The reality, however, is different but no less compelling: a team of geologists working in the Yellowstone Center for Resources in Mammoth, Wyoming. Due to an on-site presence, the NPS affiliates of YVO are primed to repair inoperative equipment (e.g., seismic stations, data loggers, etc.) and provide updates on geologic activity within the park.

The geology program at the Yellowstone Center for Resources is tasked with research into and preservation of Yellowstone's hydrothermal features. In accordance with the Code of Laws of the United States, a long-term monitoring program was established to initiate a systematic approach to monitoring the park's hydrothermal features. The cornerstone of Yellowstone's monitoring program is the acquisition of temperature data from hydrothermal areas using ground-based and airborne methods.

The monitoring program deploys and maintains data loggers with thermal sensors in the runoff channels of geysers in the Upper Geyser Basin, Lower Geyser Basin, and Norris Geyser Basin. By recording temperature at 30- to 60-second intervals, the data loggers provide indications of when geysers have erupted. In other words, when recorded temperatures exceed a certain baseline for a certain duration, a geyser eruption is implied. This method allows us to continually record the activity of specific geysers and thereby gain insight into the dynamics of the underlying hydrothermal system.

Traditionally, the monitoring program has also acquired 1 meter resolution and 1 degree Celsius accuracy thermal infrared imagery using an equipped helicopter. As described in last week's column, objects on Earth's surface — such as hydrothermal features — emit energy that is a function of the object's temperature. Although hydrothermal features are not hot enough to emit visible light, they do emit thermal infrared light that can be detected by specific sensors. This method allows us to detect changes in radiated heat from hydrothermal areas over time.

Yellowstone's alluring hydrothermal features continue to draw millions of visitors to the park every year. While visiting Yellowstone's hydrothermal areas, it is crucial to remember that they are as dangerous as they are striking. Please be cautious while viewing these features, and remain on boardwalks and designated trails while you enjoy the world's first national park.