Dorrik A. V. Stow Editor in Chief, Association of Geoscientists for International Development ( AGID) AGID is particularly pleased to see published this latest hurricanes, floods-that are wreaking havoc, destroying report in its Geosciences in International Development livelihood and lives in some corner of the globe. Series, as a significant contribution to the onset of the UN As geoscientists there are perhaps three concerns that Decade of National Disaster Reduction, and as a mark of should be uppermost in our minds as we join an inter AGID's growing concern over the potential and actual national effort to combat the adverse effects of natural effects of geohazards throughout the developing world. hazards. The first must be to improve our scientific The problem of geohazards is increasing, not because understanding of the nature and causes of such hazards and to work towards more reliable prediction of their the rate of earth processes is accelerating, nor because the occurrence and magnitude.

Attention to the problems posed by natural hazards in West and Central Africa was brought into sharp focus by the deaths of an estimated 1700 people in the valleys to the north of Lake Nyos in 1986. Prior to that the only, well documented, major natural catastrophe was the 1983 earthquake which killed at least 275 people in northwestern Guinea. Though we would not wish to appear to suggest that the 1939 Accra earthquake, which killed 16 people, or the Lake Monoun disaster, which killed 37 people in 1984, were not significant events for the areas concerned. The full horror of the Lake Nyos gas disaster was exacerbated, as far as the outside world was concerned, by initial uncertainty concerning its cause. During the first phase of the investigation there were considerable disagreements between some of the participating groups of scientists. Many of these disagreements have now been resolved and it is to be hoped that the contributions in this volume will further help to resolve some of the outstanding uncertainties. However, although it is important to understand what happened at Lake Nyos in 1986, and why it happened, it is more important for the future of that area that further similar disasters should be avoided. We can only hope that this volume will help to establish a solid foundation for future research into ways of removing excess gas from the lake.

This open access book provides a comprehensive overview of volcanic crisis research, the goal being to establish ways of successfully applying volcanology in practice and to identify areas that need to be addressed for future progress. It shows how volcano crises are managed in practice, and helps to establish best practices. Consequently the book brings together authors from all over the globe who work with volcanoes, ranging from observatory volcanologists, disaster practitioners and government officials to NGO-based and government practitioners to address three key aspects of volcanic crises. First, the book explores the unique nature of volcanic hazards, which makes them a particularly challenging threat to forecast and manage, due in part to their varying spatial and temporal characteristics. Second, it presents lessons learned on how to best manage volcanic events based on a number of crises that have shaped our understanding of volcanic hazards and crises management. Third, it discusses the diverse and wide-ranging aspects of communication involved in crises, which merge old practices and new technologies to accommodate an increasingly challenging and globalised world. The information and insights presented here are essential to tapping established knowledge, moving towards more robust volcanic crises management, and understanding how the volcanic world is perceived from a range of standpoints and contexts around the globe.