Abstract Tsunami catalogues provide important datasets in assessing the risk from infrequent but potentially high-impact events. Although the UK is located away from subduction zones (the most common origin of tsunamis), tsunamis have struck its shores, most notably those triggered by the prehistoric Storegga submarine landslide and the 1755 Lisbon earthquake. Since the major events of 2004 (Indian Ocean) and 2011 (Japan) tsunamis are in the public psyche, even if the risks to UK coasts are not. Due to this heightened awareness, many reported events are claimed to be tsunamis and the potential for tsunamis is increasingly included in risk planning; understanding the true frequency of tsunamis is therefore important. Within the UK, the evidence for tsunamis includes tide gauge readings, reported visual observations and interpretation of sedimentological features. Catalogues need to consider whether the event is a true tsunami in order to avoid a plethora of claims that confound risk assessments; for example, recent well-documented events generated by weather systems (meteotsunamis) provide a possible explanation for some historical events. A detailed examination of the impact of tsunamis upon the UK coast is provided, including examples of events triggered by the three primary causes of tsunamis: seismicity, submarine landslides and coastal landslides.

Abstract Hot springs, geysers, mud pots, and fumaroles are dynamic surface features that represent interacting subterranean systems of water, heat, and rocks. Identifying the locations of these features and monitoring their heat, water flow, and chemistry can provide land managers with data needed to make informed decisions about management options. This chapter describes vital signs and contains options for monitoring surface and near-surface geothermal features, such as hot springs, geysers, mud pots, and fumaroles. Its focus is the description of techniques for detecting change in hydrothermal systems through time due to natural or human-related causes. The goal of this chapter is to describe selected techniques for monitoring important vital signs of geothermal systems. Information in this chapter will not make the reader an expert in all geological aspects of geothermal systems. Some monitoring techniques are simple and can be performed by interested volunteers with no specialized background. Other techniques are complex and are best done by experts, with study results interpreted by seasoned practitioners. The described monitoring options may not meet all statutory and regulatory requirements that land managers may face. The terms geothermal and hydrothermal have specific connotations as used in this chapter ( Jackson, 1997 ). Geothermal refers to any system that transfers heat from within the Earth to its surface. Hot rocks, without water, are geothermal. Hydrothermal is a subset of geothermal, and means that the transfer of heat involves water, either in liquid or vapor state (hence the “hydro”). Hot springs and geysers, for example, are hydrothermal