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Monitoring Cascade Volcanoes

Active volcanoes are complex natural systems, and understanding a volcano's behaviors requires the attention of specialists from many science disciplines. It demands a combination of current knowledge about magma systems, tectonic plate motion, volcano deformation, earthquakes, gases, chemistry, volcano histories, processes, and hazards.

 Volcano eruption forecasting relies on several disciplines of volcanology.

Helicopter dropping off monitoring equipment at Mount St. Helens, W...
Helicopter dropping off monitoring equipment at Mount St. Helens, Washington. (Credit: Mosbrucker, Adam. Public domain.)
Rime ice coats telemetry station north of Mount St. Helens. ...
Rime ice coats telemetry station north of Mount St. Helens, Washington. (Credit: Mosbrucker, Adam. Public domain.)

No single tool or technique can adequately monitor or predict volcanic behaviors. Therefore, volcanologists rely on an assortment of instruments and techniques to monitor volcanic unrest. This requires placement of monitoring instruments both close to and far away from the primary source of eruptive activity (e.g. in a crater, on the crater rim, and on the volcano's flanks). By placing sensitive monitoring instruments at hazardous volcanoes in advance of the unrest, the USGS CVO helps to ensure that communities at risk can be forewarned with sufficient time to prepare and implement response plans and mitigation measures. Recommendations for the numbers and types of ground-based sensors were made by an interdisciplinary team of scientists as part of planning for the National Volcano Early Warning System. CVO uses these recommendations to plan monitoring improvements throughout the Cascades.

You can watch interviews with volcano scientists (Web Shorts) about their research and monitoring efforts and videos about volcano monitoring techniques in the Multimedia section of this website.

Cascade volcanoes present unique challenges for volcano monitoring.

The events surrounding the May 18, 1980 eruption of Mount St. Helens helped scientists to recognize some new and subtle patterns of volcanic activity that could help them forecast Cascade volcanoes' eruptions. Since then, tools for tracking the movement of magma beneath Cascade volcanoes have evolved from the use of isolated instruments to dense networks of ground-based sensors that measure earthquakes, swelling of the volcano, and emission of volcanic gases.

SWFL seismic station, on the crater rim of Mount St. Helens, was re...
SWFL seismic station, on the crater rim of Mount St. Helens, was replaced on Aug 8, 2013 with SWF2 at a lower elevation. (Credit: Bard, Joe. Public domain.)

Today, scientists rely upon remote monitoring equipment 24 hours a day and 365 days a year to deliver real-time data to the CVO. When scientists design and install monitoring stations on the Cascade volcanoes, they must consider the remoteness of sites, rough terrain, and wintry conditions. Each monitoring station contains delicate sensors, a power unit, and an antenna that can withstand strong winds, heavy snowpack, and sub-zero temperatures. Just as important to the monitoring devices are telemetry systems designed to transmit data from each volcano to the CVO. The systems are developed to relay radio signals reliably, unimpeded by miles of rugged mountainous terrain.

USGS expands volcano monitoring networks to detect volcanic restlessness.

During the past decade at Cascade volcanoes, USGS and the Pacific Northwest Seismograph Network (PNSN) have expanded monitoring networks on Mount St. HelensMount RainierMount HoodNewberry Volcano, and Crater Lake. CVO currently has plans in development to augment sparse monitoring on other hazardous Cascade volcanoes including Mount Baker and Glacier Peak. You might see these instruments on a volcano's slopes; please know that they are hard at work for communities downwind and downstream of the volcano.

To see the monitoring data for specific volcanoes within the Cascades Volcano Observatory area of responsibility, follow the links below. 


Monitored Cascade Range Volcanoes

Oregon volcanoes Washington Volcanoes
Mount Hood Glacier Peak
Mount Jefferson Mount Adams
Newberry Mount Baker
Three Sisters Mount Rainier
Crater Lake Mount St. Helens