Augustine Volcano Watch
An indication of how effective modern communications have become is that Fairbanks, in the Alaskan interior 400 miles from erupting Mount St. Augustine in Cook Inlet, is home base for the primary agency monitoring that volcano.
Augustine continues to pose a serious threat to population centers and air traffic in southcentral Alaska, yet it is the Geophysical Institute in Fairbanks that is maintaining an around-the-clock check on the volcano's pulse. It is a situation analogous to the 1980 eruption of Mount St. Helens, when the seismic monitoring was performed at the University of Washington in Seattle, while the endangered population center was Portland, much closer to the volcano.
Like St. Helens, Augustine should be watched. The worst hazard is a sea wave, which would be created if a large portion of the mountain were to fall away into the inlet. This did happen during an 1883 eruption. About 25 minutes after a heavy explosion was heard and dense clouds of smoke were seen rising from Augustine Island, an enormous wall of water reached Port Graham, near the-southern tip of the Kenai Peninsula. The wave was estimated as being from 25 to 30 feet high, and it carried off all the boats in the harbor and inundated the houses. Only the fact that it occurred when the tide was out prevented most of the people in the settlement from being swept away as well. The wave was created when most of the northern half of Augustine island was blown into the sea.
Volcanologist Juergen Kienle of the Geophysical Institute suspects that a similar episode might be developing during the present eruptive cycle, but that this time it would be the southern part of the volcano that goes--the area where there is a substantial crack that is venting steam.
A second major hazard that the volcano presents is the threat to aircraft. During the present Augustine eruptive episode, at least two cases of minor damage have been reported. These involved passenger jets of Sabena and Alaska airlines, both of which sustained sandblasted windows and minor engine damage from volcanic ash in the air.
There are cases on record where the ash fallout has completely shut down engines. An extreme example involved a British Airways 747 with 239 passengers on board in 1982. En route from Kuala Lumpur in Malaysia to Perth in Australia, the plane passed through an eruptive plume from Mount Galunggung in western Java. Because it was nighttime, the crew was unaware of what was happening, or that anything was wrong until, one by one, the engines shut down. The aircraft glided from 37,000 to 12,000 feet before the crew was able to restart the engines and prepare for an emergency landing at Jakarta.
For reasons such as these, and because it would be possible to give only a very short sea-wave or ash-fall warning to the residents of the Kenai Peninsula, the 24-hour watch on Augustine Volcano was begun at the Geophysical Institute on March 27. More than two weeks earlier, earthquake swarms of the type that are known to precede an eruption had begun. On March 22, a team from the Institute, with support from the State Division of Geological and Geophysical Surveys, had beefed up the network of four seismic stations on the island with the installation of a fifth. In addition, the Institute operates eight other stations within a 75 mile radius of the volcano.
The seismic signals from these 13 stations (plus others from around the state) are telemetered over a system of radio and telephone links to Fairbanks, where they are recorded at the Geophysical Institute on the University of Alaska campus. Thus, it is possible for an observer in Fairbanks to tell, at a glance, what the volcano in Cook Inlet is doing.
Since March 26, an alert system had been in effect which connected the Geophysical Institute with the Alaska Department of Emergency Services and other state agencies, as well as with the U.S. Geological Survey, the Federal Aviation Administration, the U.S. Air Force and the Alaska Tsunami Warning Center. The common purpose of this diverse group is to give as much warning as possible of an impending eruption. In the event that a sea wave seems likely, local Civil Defense authorities on the Kenai Peninsula would be alerted and--at least--they would attempt to move people off the Homer spit.
Also on March 26, a rapid increase in the level of seismicity on Augustine was recorded and the first alert was sounded (although it was not judged necessary to carry it down to the local level). At 2 AM the next morning, the volcano erupted. The next alert was given on March 31 at 9:55 AM, when the largest plume to date was spewed into the stratosphere.
A week later, seismic activity of the volcano had dropped back to nearly pre-eruption levels. However, some volcanologists (Kienle included) feel that it may not be over yet. For that reason, the watch continues.
