Yellowstone’s semipermanent GPS sensors head home for the winter.

Mike Poland, the ScientistinCharge of the Yellowstone Volcano Observatory, provides the October update from the warehouse at the Cascades Volcano Observatory, where the YVO field team is getting ready to head out to Yellowstone to pick up instruments that have been collecting data on ground surface changes all summer.

Yellowstone volcano is monitored by dozens of GPS stations that continuously radio information to the observatory in realtime, 24/7, 365 days a year. The deformation network also includes semipermanent GPS that are installed every May and collected in October. These instruments are not connected by a radio link, so data has to be downloaded when the instruments are back at the observatory. The primary purpose of the semipermanent GPS network is to add to the data collected by the continuous network, to gain a broad picture of changes that happen from year to year.

The semipermanent GPS is also good at collecting data on subtle changes in different areas. A good example of this is the deformation caused by Yellowstone Lake. Every spring, when the snow starts to melt, the level of Yellowstone Lake rises as it fills with water. During the summer, the lake level goes down as water drains into the outlet channel.

As the water rises in the springtime, more weight is put on the ground, and the ground around the lake subsides. As the water drains out of the lake, the ground rises because some of that water weight is removed. The weight of water causes ground deformation that can be detected by the semipermanent GPS network deployed along the shore.

The video shows the components of a semipermanent GPS station, and includes a recap of seismic activity and ground deformation at Yellowstone volcano for the past month, along with what’s going on at Steamboat Geyser.

Video:https://www.usgs.gov/media/videos/mon...