Publications

We used the volcanic ash transport and dispersion model Ash3d to estimate the distribution of ashfall that would result from a modern-day Plinian supereruption at Yellowstone volcano. The simulations required modifying Ash3d to consider growth of a continent-scale umbrella cloud and its interaction with ambient wind fields. We simulated eruptions lasting 3 days, 1 week, and 1 month, each...

Explosive eruptions of large-volume rhyolitic magma systems are common in the geologic record and pose a major potential threat to society. Unlike other natural hazards, such as earthquakes and tsunamis, a large rhyolitic volcano may provide warning signs long before a caldera-forming eruption occurs. Yet, these signs—and what they imply about magma-crust dynamics—are not well known...

Significant progress has been made over the past century in understanding, characterizing, and communicating the societal risks posed by volcanic, earthquake, and tsunami hazards in Hawai‘i. The work of the Hawaiian Volcano Observatory (HVO), with a century-long commitment to serving the public with credible hazards information, contributed substantially to this global progress. Thomas A...

Continuously operating thermal cameras are becoming more common around the world for volcano monitoring, and offer distinct advantages over conventional visual webcams for observing volcanic activity. Thermal cameras can sometimes “see” through volcanic fume that obscures views to visual webcams and the naked eye, and often provide a much clearer view of the extent of high temperature...

Active long-path differential optical absorption spectroscopy (LP-DOAS) has been an effective tool for measuring atmospheric trace gases for several decades. However, instruments were large, heavy and power-inefficient, making their application to remote environments extremely challenging. Recent developments in fibre-coupling telescope technology and the availability of ultraviolet...

The 19 known shield volcanoes of the main Hawaiian Islands—15 now emergent, 3 submerged, and 1 newly born and still submarine—lie at the southeast end of a long-lived hot spot chain. As the Pacific Plate of the Earth’s lithosphere moves slowly northwestward over the Hawaiian hot spot, volcanoes are successively born above it, evolve as they drift away from it, and eventually die and...

Hawaiian volcanoes build long rift zones and some of the largest volcanic edifices on Earth. For the active volcanoes on the Island of Hawai‘i, the growth of these rift zones is upward and seaward and occurs through a repetitive process of decades-long buildup of a magma-system head along the rift zones, followed by rapid large-scale displacement of the seaward flank in seconds to...

The characteristics of magma supply, storage, and transport are among the most critical parameters governing volcanic activity, yet they remain largely unconstrained because all three processes are hidden beneath the surface. Hawaiian volcanoes, particularly Kīlauea and Mauna Loa, offer excellent prospects for studying subsurface magmatic processes, owing to their accessibility and...

The Hawaiian Volcano Observatory (HVO) was established as a natural laboratory to study volcanic processes. Since the most frequent form of volcanic activity in Hawai‘i is effusive, a major contribution of the past century of research at HVO has been to describe and quantify lava flow emplacement processes. Lava flow research has taken many forms; first and foremost it has been a...

In September 2004, Mount St. Helens volcano erupted after nearly 18 years of quiescence. However, it is unclear from the limited geophysical observations when or if the magma chamber replenished following the 1980–1986 eruptions in the years before the 2004–2008 extrusive eruption. We use coda wave interferometry with repeating earthquakes to measure small changes in the velocity...

The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980–1986 and 2004–2008. More than three decades after the emplacement of the 1980 debris avalanche, high sediment production persists in the North Fork Toutle...

The rivers of western Oregon have diverse forms and characteristics, with channel substrates ranging from continuous alluvial gravel to bare bedrock. Analysis of several measurable morphologic attributes of 24 valley reaches on 17 rivers provides a basis for comparing nonalluvial and alluvial channels. Key differences are that alluvial reaches have greater bar area, greater migration...