David Alexander Johnston
was a volcanologist
with the United States Geological Survey
(USGS) who was killed by the 1980 eruption
of Mount St. Helens
in Washington. One of the principal scientists on the monitoring team, Johnston died while manning an observation post on the morning of May 18, 1980. He was the first to report the eruption, transmitting the famous message "Vancouver! Vancouver! This is it!" before being swept away by the lateral blast
created by the collapse of the mountain's north flank. His work and that of his fellow USGS scientists had convinced the authorities to close Mount St. Helens to the general public and to maintain the closure in spite of heavy pressure to re-open the area; their work saved thousands of lives. His story has become part of the popular image of volcanic eruptions and their threat to society, and also part of the history of volcanology. Following his death, Johnston was commemorated in several ways, including a memorial fund set up in his name at the University of Washington
, and two volcano observatories that were named after him. Johnston's life and death have been featured in several documentaries, films, docudramas and books about the eruption. Along with other people killed by the volcano, Johnston's name is inscribed on memorials dedicated to their memory.