Volcanology, the scientific study of volcanoes, is a relatively young field of earth science. Although eruptions have been observed for centuries, the systematic, long-term study of these natural hazards required intense geologic activity and a catastrophic event to galvanize global attention. Alaska is recognized worldwide as a primary location where the foundational research and institutional structures for modern volcanology were first established. The state’s unique environment provides a natural laboratory that drove the development of many monitoring techniques used by scientists today.
The Geological Setting of the Aleutian Arc
The tremendous concentration of volcanoes in Alaska is a direct consequence of its location on the Pacific Ring of Fire, specifically along the Aleutian Arc. This 3,000-kilometer-long chain of volcanic islands and the Alaska Peninsula is a classic example of a subduction zone. The dense Pacific Plate is actively sliding beneath the lighter North American Plate at the Aleutian Trench, a process that occurs at a rate ranging from 51 to 75 millimeters per year.
As the Pacific Plate descends into the Earth’s mantle, increasing pressure and temperature cause the release of water from the subducting slab. This water rises into the overlying North American Plate, lowering the melting point of the rock and generating magma. The magma then ascends to the surface, feeding the roughly 50 historically active volcanic centers that define the arc. This active and diverse environment provides an unparalleled setting for studying different eruptive styles, magma compositions, and precursory signals.
The Catalyst: The 1912 Novarupta Eruption
The event that truly started the systematic study of Alaskan volcanoes was the 1912 Novarupta eruption on the Alaska Peninsula. Spanning approximately 60 hours in early June, this VEI 6 event was the most voluminous explosive eruption of the 20th century. It vented an enormous volume of material, estimated to be around 13.5 cubic kilometers of magma, including widespread fallout and dense ash flows.
This sheer magnitude and the resulting landscape transformation immediately drew international scientific attention to the remote region. The eruption produced unique features, including the Valley of Ten Thousand Smokes, which was filled with hot ash flows that sustained high-temperature fumaroles for over a decade. Early scientific expeditions, notably those led by the U.S. Geological Survey and the National Geographic Society starting in 1915, faced arduous conditions to study these deposits.
The complex nature of the eruption—where magma vented at Novarupta but caused the collapse of Mount Katmai’s summit 10 kilometers away—provided unprecedented insights into magma plumbing systems. These early, difficult expeditions marked the beginning of long-term, government-funded research programs focused on the unique geology of the Aleutian Arc. The study of the 1912 deposits has continued for a century, providing foundational knowledge on ash-flow tuffs and magmatic processes.
Formalizing Research: The Role of the Alaska Volcano Observatory
The sustained threat demonstrated by the 1912 Novarupta event and subsequent eruptions led to the establishment of the Alaska Volcano Observatory (AVO). Founded in 1988, AVO is a collaborative effort between the U.S. Geological Survey, the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys. Its creation institutionalized the continuous monitoring necessary for this active volcanic region.
The observatory’s mission focuses on mitigating hazards to international air travel, as many active volcanoes lie directly beneath the high-volume Great Circle Route. Volcanic ash clouds, composed of sharp glass and rock fragments, pose an extreme risk to jet engines and aircraft systems. Because of this specific aviation threat, AVO pioneered many of the communication and monitoring protocols now used globally.
For instance, AVO developed the color-coded alert system for aviation during the 1989–1990 eruption of Redoubt Volcano. This system uses a simple ranking of Green, Yellow, Orange, and Red to communicate the level of volcanic ash hazard. This system has since been adopted by the International Civil Aviation Organization (ICAO) and is a standard for volcano observatories worldwide. AVO’s integration of seismic data, satellite imagery, and ground deformation measurements established the model for sustained, multi-parameter volcano monitoring.