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New Volcanic Gas Monitoring Station Installed at Mount St. Helens.

September 4, 2014

This summer, a new monitoring station was installed on the lava dome in the crater of Mount St. Helens to "sniff" volcanic gases.

Like most volcanoes, the majority of the gas emitted at Mount St. Helens is water vapor (H2O) and carbon dioxide (CO2) with lesser amounts of sulfur dioxide (SO2) and hydrogen sulfide (H2S). In the past, scientists would visit sites inside the crater or conduct airborne surveys to collect gas emission data. With this new station, gas concentrations can be measured daily and the monitoring data sent back to the Cascades Volcano Observatory via radio link for analysis. Monitoring the chemical composition of these gases offers important clues to the inner workings of the volcano. An increase in gas output or a change in the ratios of the different gases can be some of the first above-ground signs of an increase or important change in volcanic activity. Read more about volcanic gas monitoring at Mount St. Helens.