Volume 30 of Reviews in Mineralogy introduces in understanding the behavior of magmatic volatiles and their influence on a wide variety of geological phenomena; in doing this it also becomes apparent that there remain many questions outstanding. The range of topics we have tried to cover is broad, going from atomisticscale aspects of volatile solubility mechanisms and attendant effects on melt physical properties, to the chemistry of volcanic gases and the concentrations of volatiles in magmas, to the global geochemical cycles of volatiles. The reader should quickly see that much progress has been made since Bowen voiced his concerns about Maxwell demons, but like much scientific progress, answers to old questions have prompted even greater numbers of new questions. The Voltiles in Magmas course was organized and transpired at the Napa Valley Sheraton Hotel in California, December 2-4, 1994, just prior to the Fall Meetings of the American Geophysical Union in San Francisco.

Remote sensing data and methods are increasingly being implemented in assessments of volcanic processes and risk. This happens thanks to their capability to provide a spectrum of observation and measurement opportunities to accurately sense the dynamics, magnitude, frequency, and impacts of volcanic activity. This book includes research papers on the use of satellite, aerial, and ground-based remote sensing to detect thermal features and anomalies, investigate lava and pyroclastic flows, predict the flow path of lahars, measure gas emissions and plumes, and estimate ground deformation. The multi-disciplinary character of the approaches employed for volcano monitoring and the combination of a variety of sensor types, platforms, and methods that come out from the papers testify to the current scientific and technology trends toward multi-data and multi-sensor monitoring solutions. The added value of the papers lies in the demonstration of how remote sensing can improve our knowledge of volcanoes that pose a threat to local communities; back-analysis and critical revision of recent volcanic eruptions and unrest periods; and improvement of modeling and prediction methods. Therefore, the selected case studies also demonstrate the societal impact that this scientific discipline can potentially have on volcanic hazard and risk management.

Volcanoes release plumes of gas and ash to the atmosphere during episodes of passive and explosive behavior. These ejecta have important implications for the chemistry and composition of the troposphere and stratosphere, with the capacity to alter Earth's radiation budget and climate system over a range of temporal and spatial scales. Volcanogenic sulphur dioxide reacts to form sulphate aerosols, which increase global albedo, e.g., by reducing surface temperatures, in addition to perturbing the formation processes and optical properties of clouds. Released halogen species can also deplete stratospheric and tropospheric ozone. Volcanic degassing, furthermore, played a key role in the formation of Earth’s atmosphere, and volcanic plumes can affect air quality, pose hazards to aviation and human health, as well as damage ecosystems. The chemical compositions and emission rates of volcanic plumes are also monitored via a range of direct-sampling and remote-sensing instrumentation, in order to gain insights into subterranean processes, in the respect of the magmatic bodies these volatiles exsolve from. Given the significant role these gases play in driving volcanic activity, e.g., via pressurisation, the study of volcanic plumes is proving to be an increasingly fruitful means of improving our understanding of volcanic systems, potentially in concert with observations from geophysics and contributions from fluid dynamical modelling of conduit dynamics. This Special Issue is aimed at presenting the state of the art of the multidisciplinary science concerning all aspects of volcanic plumes, of relevance to the volcanology, climatology, atmospheric science, and remote sensing communities.

Forecasting and Planning for Volcanic Hazards, Risks, and Disasters expands and complements the subject and themes in Volcanic Hazards, Risks and Disasters. Together, the two volumes represent an exhaustive compendium on volcanic hazards, risks, and disasters. Volume two presents a comprehensive picture of the volcano dynamics relevant for volcanic hazard forecasts. It also includes case studies of the associated risks and aspects like operational volcano observatory responses, communication before and across volcanic crises, emergency planning, social science aspects, and resilience from volcanic disasters. Forecasting and Planning for Volcanic Hazards, Risks, and Disasters takes a geoscientific approach to the topic while integrating the social and economic issues related to volcanoes and volcanic hazards and disasters. - Features the expertise of top volcanologists, seismologists, geologists, and geophysicists - Presents the latest research - including case studies of prominent volcanoes and volcanic hazards and disasters - on causality, economic and social impacts, and preparedness and mitigation - Includes numerous tables, maps, diagrams, illustrations, and photographs to aid in grasping key concept