File:The Legacy of David A. Johnston (17754441319).jpg

We take a look back on this #TBT to honor one of our own, David A. Johnston.

Dave a 30-year-old volcanologist with the U.S. Geological Survey, was swept away by the catastrophic eruption of Mount St. Helens on the morning of May 18, 1980. As one of the first members of the U.S. Geological Survey monitoring team to arrive at Mount St. Helens, and the scientist in charge of volcanic-gas studies, Dave spent long hours working on and close to the mountain.

From his experience with active Alaskan volcanoes, Dave understood better than most the hazards of explosive volcanism. Dave helped persuade the authorities first to limit access to the area around the volcano, and then to resist heavy pressure to reopen it, thereby holding the May 18 death toll to a few tens instead of hundreds or thousands.

His work on volcanic gases brought him to the USGS in 1978, where he was assigned to expand the program for monitoring volcanic emissions in Alaska and the Cascade Range. A specific objective of such monitoring is to test whether or not changes in gas geochemistry might provide precursory clues of impending eruptive activity. Thus, it was natural that, when Mount St. Helens reawakened in March 1980, Dave Johnston was one of the first geologists on the volcano.

We honor this exemplary scientist for his dedication and infectious enthusiasm. Dave would have expected us to carry on without him, learning all we could from Mount St. Helens and applying the knowledge gained to other volcanoes for the betterment of the science and public safety.

For more information on David A. Johnston and the eruption of Mount St. Helens 35 years ago, please see "The 1980 Eruptions of Mount St. Helens, Washington:"