Fatalism about natural disasters hinders action to prepare for those disasters, and overcoming this fatalism is one key element to preparing people for these disasters. Research by Bostrom and colleagues shows that failure to act often reflects gaps and misconceptions in citizen’s mental models of disasters. Research by McClure and colleagues shows that fatalistic attitudes reflect people’s attributing damage to uncontrollable natural causes rather than controllable human actions, such as preparation. Research shows which precise features of risk communications lead people to see damage as preventable and to attribute damage to controllable human actions. Messages that enhance the accuracy of mental models of disasters by including human factors recognized by experts lead to increased preparedness. Effective messages also communicate that major damage in disasters is often distinctive and reflects controllable causes. These messages underpin causal judgments that reduce fatalism and enhance preparation. Many of these messages are not only beneficial but also newsworthy. Messages that are logically equivalent but are differently framed have varying effects on risk judgments and preparedness. The causes of harm in disasters are often contested, because they often imply human responsibility for the outcomes and entail significant cost.
Dennis John Parker
Humankind is becoming increasingly dependent on timely flood warnings. Dependence is being driven by an increasing frequency and intensity of heavy rainfall events, a growing number of disruptive and damaging floods, and rising sea levels associated with climate change. At the same time, the population living in flood-risk areas and the value of urban and rural assets exposed to floods are growing rapidly. Flood warnings are an important means of adapting to growing flood risk and learning to live with it by avoiding damage, loss of life, and injury. Such warnings are increasingly being employed in combination with other flood-risk management measures, including large-scale mobile flood barriers and property-level protection measures.
Given that lives may well depend on effective flood warnings and appropriate warning responses, it is crucial that the warnings perform satisfactorily, particularly by being accurate, reliable, and timely. A sufficiently long warning lead time to allow precautions to be taken and property and people to be moved out of harm’s way is particularly important. However, flood warnings are heavily dependent on the other components of flood forecasting, warning, and response systems of which they are a central part. These other components—flood detection, flood forecasting, warning communication, and warning response—form a system that is characterized as a chain, each link of which depends on the other links for effective outcomes. Inherent weaknesses exist in chainlike processes and are often the basis of warning underperformance when it occurs.
A number of key issues confront those seeking to create and successfully operate flood warning systems, including (1) translating technical flood forecasts into warnings that are readily understandable by the public; (2) taking legal responsibility for warnings and their dissemination; (3) raising flood-risk awareness; (4) designing effective flood warning messages; (5) knowing how best and when to communicate warnings; and (6) addressing uncertainties surrounding flood warnings.
Flood warning science brings together a large body of research findings from a particularly wide range of disciplines ranging from hydrometeorological science to social psychology. In recent decades, major advances have been made in forecasting fluvial and coastal floods. Accurately forecasting pluvial events that cause surface-water floods is at the research frontier, with significant progress being made. Over the same time period, impressive advances in a variety of rapid, personalized communication means has transformed the process of flood warning dissemination. Much is now known about the factors that constrain and aid appropriate flood warning responses both at the individual and at organized, flood emergency response levels, and a range of innovations are being applied to improve response effectiveness. Although the uniqueness of each flood and the inherent unpredictability involved in flood events means that sometimes flood warnings may not perform as expected, flood warning science is helping to minimize these occurrences.
Brett F. Sanders
Communities facing urban flood risk have access to powerful flood simulation software for use in disaster-risk-reduction (DRR) initiatives. However, recent research has shown that flood risk continues to escalate globally, despite an increase in the primary outcome of flood simulation: increased knowledge. Thus, a key issue with the utilization of urban flood models is not necessarily development of new knowledge about flooding, but rather the achievement of more socially robust and context-sensitive knowledge production capable of converting knowledge into action. There are early indications that this can be accomplished when an urban flood model is used as a tool to bring together local lay and scientific expertise around local priorities and perceptions, and to advance improved, target-oriented methods of flood risk communication.
The success of urban flood models as a facilitating agent for knowledge coproduction will depend on whether they are trusted by both the scientific and local expert, and to this end, whether the model constitutes an accurate approximation of flood dynamics is a key issue. This is not a sufficient condition for knowledge coproduction, but it is a necessary one. For example, trust can easily be eroded at the local level by disagreements among scientists about what constitutes an accurate approximation.
Motivated by the need for confidence in urban flood models, and the wide variety of models available to users, this article reviews progress in urban flood model development over three eras: (1) the era of theory, when the foundation of urban flood models was established using fluid mechanics principles and considerable attention focused on development of computational methods for solving the one- and two-dimensional equations governing flood flows; (2) the era of data, which took form in the 2000s, and has motivated a reexamination of urban flood model design in response to the transformation from a data-poor to a data-rich modeling environment; and (3) the era of disaster risk reduction, whereby modeling tools are put in the hands of communities facing flood risk and are used to codevelop flood risk knowledge and transform knowledge to action. The article aims to inform decision makers and policy makers regarding the match between model selection and decision points, to orient the engineering community to the varied decision-making and policy needs that arise in the context of DRR activities, to highlight the opportunities and pitfalls associated with alternative urban flood modeling techniques, and to frame areas for future research.
Populations that are rendered socially invisible by their relegation to realms that are excluded—either physically or experientially—from the rest of society tend to similarly be left out of community disaster planning, often with dire consequences. Older adults, persons with disabilities, linguistic minorities, and other socially marginalized groups face amplified risks that translate into disproportionately negative outcomes when disasters strike. Moreover, these disparities are often reproduced in the aftermath of disasters, further reinforcing preexisting inequities. Even well-intentioned approaches to disaster service delivery have historically homogenized and segregated distinct populations under the generic moniker of “special needs,” thereby undermining their own effectiveness at serving those in need.
The access and functional needs perspective has been promoted within the emergency management field as a practical and inclusive means of accommodating a range of functional capacities in disaster planning. This framework calls for operationalizing needs into specific mechanisms of functional support that can be applied at each stage of the disaster lifecycle. Additionally, experts have emphasized the need to engage advocacy groups, organizations that routinely serve socially marginalized populations, and persons with activity limitations themselves to identify support needs. Incorporating these diverse entities into the planning process can help to build stronger, more resilient communities.
Maria Papathoma-Köhle and Dale Dominey-Howes
The second priority of the Sendai Framework for Disaster Risk Reduction 2015–2030 stresses that, to efficiently manage risk posed by natural hazards, disaster risk governance should be strengthened for all phases of the disaster cycle. Disaster management should be based on adequate strategies and plans, guidance, and inter-sector coordination and communication, as well as the participation and inclusion of all relevant stakeholders—including the general public. Natural hazards that occur with limited-notice or no-notice (LNN) challenge these efforts.
Different types of natural hazards present different challenges to societies in the Global North and the Global South in terms of detection, monitoring, and early warning (and then response and recovery). For example, some natural hazards occur suddenly with little or no warning (e.g., earthquakes, landslides, tsunamis, snow avalanches, flash floods, etc.) whereas others are slow onset (e.g., drought and desertification). Natural hazards such as hurricanes, volcanic eruptions, and floods may unfold at a pace that affords decision-makers and emergency managers enough time to affect warnings and to undertake preparedness and mitigative activities. Others do not. Detection and monitoring technologies (e.g., seismometers, stream gauges, meteorological forecasting equipment) and early warning systems (e.g., The Australian Tsunami Warning System) have been developed for a number of natural hazard types. However, their reliability and effectiveness vary with the phenomenon and its location. For example, tsunamis generated by submarine landslides occur without notice, generally rendering tsunami-warning systems inadequate.
Where warnings are unreliable or mis-timed, there are serious implications for risk governance processes and practices. To assist in the management of LNN events, we suggest emphasis should be given to the preparedness and mitigation phases of the disaster cycle, and in particular, to efforts to engage and educate the public. Risk and vulnerability assessment is also of paramount importance. The identification of especially vulnerable groups, appropriate land use planning, and the introduction and enforcement of building codes and reinforcement regulations, can all help to reduce casualties and damage to the built environment caused by unexpected events. Moreover, emergency plans have to adapt accordingly as they may differ from the evacuation plans for events with a longer lead-time. Risk transfer mechanisms, such as insurance, and public-private partnerships should be strengthened, and redevelopment should consider relocation and reinforcement of new buildings. Finally, participation by relevant stakeholders is a key concept for the management of LNN events as it is also a central component for efficient risk governance. All relevant stakeholders should be identified and included in decisions and their implementation, supported by good communication before, during, and after natural hazard events.
The implications for risk governance of a number of natural hazards are presented and illustrated with examples from different countries from the Global North and the Global South.