BACKGROUND AND AIMS The Soufriere Hills volcano, Montserrat, has been erupting since July 1995 and volcanic ash has fallen on the island throughout most of the eruption. The ash contains substantial quantities of respirable particles and unusually large amounts (15-20%) of the crystalline silica mineral, cristobalite. The purpose of the surveys described here, undertaken between December 1996 a...

To the Editor — Detailed analysis of volcanic materials1 allows the study of eruptions that have not been witnessed directly. Rotella et al.2 undertake the challenge of interpreting submarine volcaniclastic deposits around Macauley Volcano, part of the Kermadec Arc in the southwest Pacific Ocean. They propose a ‘Tangaroan’ eruption style, based on the textural characteristics of dredged pumice ...

Volcanic eruptions caused major weather and climatic changes on timescales ranging from hours to centuries in the past. Volcanic particles are injected in the atmosphere both as primary particles rapidly deposited due to their large sizes on time scales of minutes to a few weeks in the troposphere, and secondary particles mainly derived from the oxidation of sulfur dioxide. These particles are ...

Glaciers and ice sheets on many active volcanoes are rapidly receding. There is compelling evidence that melting of ice during the last deglaciation triggered a dramatic acceleration in volcanic activity. Will melting of ice this century, which is associated with climate change, similarly affect volcanic activity and associated hazards? This paper provides a critical overview of the evidence th...

A suite of spatially distributed, multi-century cores collected since 1995 under NASA's Program for Arctic Regional Climate Assessment (PARCA) provides an excellent archive of volcanic emissions reaching Greenland. As records of equiv­ alent quality from higher accumulation sites in Antarctica become available, their integration will produce a richer, better temporally constrained and more clim...

Geophysical imaging by using attenuation property of multichannel seismic reflection data was tested to map spatial variation of physical properties of rocks in a volcanic area. The study area is located around Miyakejima volcanic island, where an intensive earthquake swarm was observed associated with 2000 Miyakejima eruption. Seismic reflection survey was conducted five months after the swarm...

Historical records show that the A.D. 1783-1784 Laki eruption in Iceland caused severe environmental stress and posed a health hazard far beyond the borders of Iceland. Given the reasonable likelihood of such an event recurring, it is important to assess the scale on which a future eruption could impact society. We quantify the potential health effects caused by an increase in air pollution dur...

Evidence is presented supporting the identification of a discrete, well-preserved air fall deposit generated by explosive volcanism on Mars. The deposit is located immediately to the west of the summit caldera of Hecates Tholus (32øN, 209øW), the northernmost of the three volcanic constructs in the Elysium Planitia region. The absence of superposed impact craters larger than the resolution limi...

Many years of low growth identified in a western USA regional chronology of upper forest border bristlecone pine (Pinus longaeva and Pinus aristata) over the last 5000 yr coincide with known large explosive volcanic eruptions and/or ice core signals of past eruptions. Over the last millennium the agreement between the tree-ring data and volcano/ice-core data is high: years of ring-width minima ...

We examined recent volcanic cloud events in the Western Pacific and Indonesian area, to validate the performance of remote sensing techniques used to support the International Airways Volcano Watch (IAVW). Five events were considered, during which eruptions from eight volcanoes injected ash into the upper troposphere or lower stratosphere. For one of the eruptions, at Miyakejima, Japan, at leas...