David A. Johnston

David A. Johnston
David A. Johnston, 13 hours before his death at the 1980 eruption of Mount St. Helens
Born	David Alexander Johnston December 18, 1949 Oak Lawn, Illinois
Died	May 18, 1980 (aged 30) Skamania County, Washington
Cause of death	Killed by the volcanic eruption of Mount St. Helens
Nationality	American

David Alexander Johnston (December 18, 1949 – May 18, 1980) was a volcanologist with the United States Geological Survey (USGS) who was killed by the 1980 eruption of the Mount St. Helens volcano in Washington. One of the principal scientists on the monitoring team, Johnston was killed while manning an observation post about 6 miles (10 km) from the volcano 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. Ham radio operator Jerry Martin observed the lateral blast overtaking Johnston's camp. Though Johnston's remains have never been found, remnants of his USGS trailer were found by state highway workers in 1993.

Johnston was a meticulous and talented volcanologist, and after his death, many of his co-workers commemorated him. All agreed that Johnston's very open-minded nature allowed him to accept any possibilities for an eruption, allowing him to be a brilliant scientist. His image is cemented into the popular culture's image of volcanic eruptions and their threat to society. To date, Johnson is one of just two American volcanologists who have been killed in volcanic eruptions.

Life and career

Johnston was born in Oak Lawn, Illinois to Thomas and Alice Johnston, and grew up with one sister. He never married. After graduating from high school, Johnston went on to run competitively, enjoy photography, and maintain excellent grades at the University of Illinois at Urbana-Champaign, where he studied geology. He graduated with "Highest Honors and Distinction" in 1971. At first just interested in the study of volcanism, his admiration for volcanoes grew as he analyzed Precambrian rock at Michigan's North Peninsula. There he discovered the remains of an ancient structure, and became fascinated with volcanoes. His interest now piqued, Johnston soon studied the San Juan volcanic field in Colorado and other features over the next few years. Beginning in 1976, after Mount Augustive erupted, Johnston helped to essentially prove that the volcano's eruptions had, over time, reduced in pumice material and were caused by basalt magmas. At that point, he had been developing a thesis on the Cimmaron Volcano in San Juan; he changed his mind. In 1978, he completed his Ph.D. at the University of Washington in Seattle, instead a study of the Mount Augustine volcano in Alaska, and in only 25 months. After completing his Ph.D. Johnston progressed to study volatiles' involvement in volcanic activity at Mount Katmai, the site of a massive explosive eruption in the early 20th century. He returned to Augustive Volcano each year, and visited Katmai several more times.

Johnston completed his thesis for his Ph.D. on the Mount Augustine volcano.

Later in 1978 he joined the United States Geological Survey (USGS), where he monitored volcanic emission levels in the volcanic ranges of the Northwestern United States and Alaska, particularly the Cascades. There he helped to strengthen the theory that eruptions can be predicted, to some degree, by changes in the makeup of volcanic gases. His work at Mount Katmai paved the way for his career – he was now known in his field for his exceptional ability to pursue only high-quality samples. Wes Hildreth noted in a dedication paper that "Dave's agility, nerve, patience, and determination around the jet-like summit fumaroles in the crater of Mt. Mageik were to me a spectacle of unforgettable beauty."

At the time of the eruption, Johnston was working at the Menlo Park, California branch of USGS. When the first earthquakes shook the Mount St. Helens on March 16, Johnston was at the University of Washington, where he had pursued his doctorate. Intrigued by the possible advent of an eruption, Johnston contacted Dr. Stephen Malone, a professor of geology at the university. Malone states that he "put him to work" almost instantly, allowing Johnston to escort interested reporters to a place near the volcano. Johnston soon became a leader for the USGS team, taking charge of monitoring of volcanic gas emissions.

The eruption

Precursor activity

Many phreatic eruptions took place at the volcano preceding its explosive eruption on May 18, 1980.

Since its last eruption(s) in the mid-19th century, Mount St. Helens had been largely dormant. In fact, seismographs were not installed until 1972. This period of more than 100 years of inactivity was ended in early 1980. On March 15, a cluster of tiny earthquakes rocked the area around the mountain. For six days, more than 100 earthquakes took place in proximity to the mountain, possibly suggesting that St. Helens was undergoing significant magmatic change. There was initially some doubt as to whether the earthquakes were just part of a cluster or precursors. By March 20, a magnitude 4.2 earthquake shook the wilderness around the volcano. In response, the next day, seismologists installed three seismic recorder stations. After the 25th, a dramatic incline in seismic activity appeared. By March 24, volcanologists at USGS – including Johnston – were sure that this could be a sign of volcanic activity. By March 26, more than seven earthquakes over 4.0 had been recorded, and the next day, hazard warnings were publicly issued. On March 27, a phreatic eruption took place, ejecting a plume of ash nearly 7,000 feet (2,134 m) into the air.

Similar activity continued at the volcano, excavating the crater, forming an adjacent caldera, and erupting small amounts of steam, ash, and bits of tephra. With each new week, the plumes of steam and ash from the volcano rose, eventually climbing to 20,000 feet (6,096 m). By late March, it was erupting up to 100 times daily. Spectators gathered continuously about the vicinity of the mountain, hoping for a chance to see its eruptions, joined by intrigued reporters on helicopters and earnest climbers.

On April 17, a bulge was discovered on the mountain's north flank, suggestive that Mount St. Helens was going to produce a lateral blast. Johnson was one of few people who believed this, along with a professor of geology at a Tacoma community college (Jack Hyde). Observing that Mount St. Helens didn't visibly possess vents, Hyde suggested that pressure would increase until the mountain exploded; his idea, seeing as he was not a part of the USGS or in a position of responsibility, was largely dismissed. Both, in fact, were correct. Instead of rising in a straight, upward line, the magma under St. Helens rose. Then, for some reason unbeknowst to volcanologists, went on a tangent and redirected itself into the volcano's north flank, thus creating the bulge.

Final signs and primary blast

Johnston and the other volcanologists working at USGS in its Vancouver branch were now forced to prepare for something. Establishing a new station just 6 miles (10 km) from the mountain, the team was now able to study the development of the bulge in depth, named Coldwater II. Almost right away, it became clear that the bulge was growing at an alarming rate, so measurements would be needed regularly. Then, an evaluation of the volcano's threat to life was facilitated, concluding that a landslide or avalanche in the Toutle River could spawn lahars, or mudflows, downstream.

File:Glicken.jpg

Harry Glicken intended to be at the observation point on the day of the eruption, but left for an urgent meeting, leaving Johnston to take his place.

Installed tiltmeters on the volcano's north side displayed a northwest trending tilt on the mountain, as well as a southwest trending tilt on the south side. Worried that the amount of pressure on the magma underground was increasing, scientists analyzed gases by the crater, and found high traces of sulfur dioxide. After that, they regularly checked the fumarolic activity and monitored the volcano for dramatic changes, but none came. They opted to study the growing bulge and the threat an avalanche could have for humans relatively near the volcano. The only strange thing about the recent activity at that point for USGS was simply that there was a lack of phreatic explosions. Instead of regularly erupting, the phreatic activity was now intermittent. Until May 7, this phenomenon continued, worrying scientists. Between May 10 and May 17, the only change occurred on the volcano's north flank, as the bulge increased in size. On May 16, the mountain stopped its phreatic eruptions completely, and did the same the next day.

The volcano was now extremely different from how it was while dormant, now featuring an enormous bulge and several craters. In the week preceding the eruption, cracks formed in the north sector of the volcano's summit, indicating a movement of magma towards the caldera (from the bulge). The day before the volcano, USGS geologist Harry Glicken was scheduled to observe Mount St. Helens. Because of an interview at a California college, Glicken was fatefully replaced by Johnston on May 17, 1980. Positioned at Coldwater II, Johnston was to observe the volcano for any further signs of an eruption. Just prior to his departure, at 7 pm on the evening of May 17, 13 1/2 hours before the eruption, Glicken took a photograph of Johnston sitting with a computer on his lap, smiling.

In the early morning of the next day, an earthquake measuring 5,1 on the Richter scale rocked the area. The oscillation from this tremor loosened 2.7 cubic kilometers (1 cu mi) of rock, creating a massive landslide. Up to 400 metres (1,312 ft) of rock was knocked off the volcano, including the bulge. With the pressure on it now relieved, the caldera of Mount St. Helens began to rapidly emit steam and other volcanic gases. Soon after, it erupted laterally, sending swift pyroclastic flows and lahars down its flanks at a near supersonic speed. Before being struck by a series of flows, Johnston managed to radio "Vancouver! Vancouver! This is it!" to his USGS co-workers. Seconds later, the signal from the radio went blank.

Famous for calling the mountain a "dynamite keg with the fuse lit", Johnston supported the lateral blast theory; he believed the volcano's explosion would be ejected straight out of the volcano, not upward. He may have believed that the eruption would originate from the bulge, though this is unclear. Nonetheless, Johnston was aware of the volcano's threat. He was among the first volcanologists at the volcano when eruptive signs appeared, where he was named the head of monitoring the volcano's gases. He was known for a very careful and studious nature when evaluating a volcano's threat of eruption, choosing to conduct dangerous "on-site monitoring". He strongly believed that scientists needed to take this risk for themselves, in order to prevent civilian deaths, and succeeded with his effort to do this at St. Helens. Johnson and several other alarmed volcanologists prevented people from being near the volcano during the few months of pre-eruptive activity, later ignoring the public argument over opening the area in proximity to Helens again. Through his long hours of work, Johnston understood the signs of an explosive eruption and the enormous threat St. Helens posed to humans.

Effects and response

Johnston was the only geologist with the USGS to correctly predict the nature of the eruption. The official USGS prediction was that the volcano would experience a conventional vertical column eruption, while Johnston (who had been doing extensive research on the volcano and the geologic forces at play within and around it) had proposed that the blast would be lateral and originate from the bulge which he had observed developing on the side of the mountain.

While many were shocked by Johnston's death, most of his co-workers and family asserted that Johnston died "doing what he wanted to do." His mother made statements in an interview shortly after the eruption. "Not many people get to do what they really want to do in this world, but our son did. [...] He would tell us he may never get rich but he was doing what he wanted. He wanted to be near if the eruption came. In a phone call on Mother's Day, he told us it's a sight very few geologists get to see."

Legacy

Johnston, affectionately nicknamed Dave, was commemorated by both his co-workers and by the government. Known for his diligent and particular nature, he was called "an exemplary scientist" by a USGS dedication paper, which also described him as "unaffectedly genuine, with an infectious curiosity and enthusiasm." He was quick to "dissipate cynicism" and believed that "careful evaluation and interpretation" was the best approach to his work. Co-worker Andrew Alden states that Johnston had great potential, declaring that he "had many friends and a bright future".

Johnston Ridge from the Observatory.

Because Johnston was believed to be safe at Coldwater Ridge II, the fact that he died shocked his friends and co-workers alike. However, Dr. Stephen Malone describes Johnston as a "fire dog"; he believes Johnston died in a way that he would have preferred. He also argued that Johnston "was very good at his work." After his death, Johnston's field of study, predicting volcanic eruptions, was advanced. Geologists have made strides, since discovering long-period earthquakes, studying the amount of magmatic gases that a volcano emits, and attentive study to uplift probably from intrusive magma. Improved and efficient technology now monitors many active volcanoes and could allow seismologists and volcanologists to effectively predict an eruption.

Despite volcanologist deaths in later eruptions at Mount Unzen and Galeras, the prediction theory allowed scientists to convince settlements near the Mount Pinatubo volcano to evacuate, preventing thousands of deaths. In addition to his work, Johnston himself is cemented into the history of volcanic eruptions. With Harry Glicken, he is one of two volcanologists from the United States to die in a volcanic eruption. Ironically, Glicken was a mentor of Johnston, who would have taken up the post Johnston did, but instead went to California for a meeting at a university. Glicken died from a pyroclastic flow at Unzen Volcano in Japan.

In commemoration, the area where Coldwater II had been was sectioned off. Eventually, a observatory was built in Johnston's name. Located just over 5 miles (8 km) from the north flank of Mount St. Helens, the observatory boasts a public opportunity to admire the open crater, new activity, and the debris of the 1980 eruption. Part of the Mount St. Helens National Volcanic Monument, the Johnston Ridge Observatory was constructed for USD 10.5 million, equipped with monitoring equipment. It also includes tours, a theater, and an exhibit hall. Most importantly, the Observatory, which is the station most responsible for monitoring St. Helens, helped to predict each and every one of the eruptions at the volcano between 1980 and 1985.

David Huffman starred as a renamed Johnston (David Jackson) in the film St. Helens, where, controversially, his character became involved in a love affair and was killed by the blast while on top of the mountain. Johnston's parents criticized the production of the film, arguing that it possessed not "an ounce of David in it" and portrayed "him as a daredevil rather than a careful scientist". In fact, they threatened to sue over the fact that they felt their son's memory had been contaminated. Mrs. Johnston stated that the film had changed many true aspects of the eruption, and depicted her son as "a rebel" with "a history of disciplinary trouble".

See also

• Harry Randall Truman
• List of volcanoes in the United States of America

External links

• Obituary on the USGS web site
• A life in science sometimes becomes a death, too, an article in The San Diego Union-Tribune.
• David A. Johnston at Find-A-Grave