EARTH SCIENCE AND SOCIETY: ADVANCES IN NATURAL HAZARD SCIENCE AND ASSESSMENT, 1963–2013

Natural hazard assessments provide society with information on the size, location and likelihood of future hazardous events, as well as quantify their potential impacts and consequences. Hazard maps, event forecasts, and hazard assessments are used by society for guiding evacuation, establishing insurance premiums, in building codes, and in land use planning. In the past 50 years natural hazard science and assessment came into its own as a distinct discipline in part due to several key scientific and technological advances: (1) establishment of plate tectonics theory as a unifying framework; (2) high dynamic range monitoring sensors made possible by the digital technology revolution; (3) land-based, airborne and satellite capabilities for real-time data acquisition and processing; (4) development of probabilistic hazard analysis methodology; and finally (5) an important movement toward data transparency, open access, and near real-time forecasting and impact assessment. Major scientific advances that have dramatically improved our ability to carry out earthquake hazard assessments include: identification and mapping of active faults, development of paleoseismology to determine history of past earthquakes, geodetic monitoring and modeling of strain accumulation, the Gutenberg-Richter magnitude/frequency power-law relationship, stress transfer and Coulomb failure analysis, and ground motion prediction. Key breakthroughs in tsunami hazard science assessment include: identification of past tsunamis in the geologic record, constraints on tsunami character of different source types, ocean buoy systems for tsunamis detection and recording, and hydrodynamic modeling to predict runup and inundation. Volcanic hazard assessment has arisen from a number of scientific advances including: development of the volcanic explosivity index, recognition that volcanic eruptions produce both constructive and destructive landforms, understanding of physio-chemical constraints on explosivity, use of seismic signals to constrain mass transport processes, development of eruption forecasting methodology, recognition of hazards posed by volcanic ash and gases, and physical modeling of volcanic eruption processes enabling prediction of the aerial and spatial distribution of volcanic products.