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Allison Hoadley Anderson
In architecture, mitigation reduces the magnitude of climate change by reducing demand for resources; anticipatory adaptation improves performance against hazards; and planned adaptation creates policies and codes to support adaptation.
Adaptation prepares for a future with intensifying climate conditions. The built environment must prepare for challenges that may be encountered during the service life of the building, and reduce human exposure to hazards. Structures are responsible for about 39% of the primary energy consumption worldwide and 24% of the greenhouse gas emissions, significantly contributing to the causes of climate change. Measures to reduce demand in the initial construction and over the life cycle of the building operation directly impact the climate.
Improving performance against hazards requires a suite of modifications to counter specific threats. Adaptation measures may address higher temperatures, extreme precipitation, stormwater flooding, sea-level rise, hurricanes, drought, soil subsidence, wildfires, extended pest ranges, and multiple hazards. Because resources to meet every threat are inadequate, actions with low costs now which offer high benefits under a range of predicted future climates become high-priority solutions.
Disaster risk is also reduced by aligning policies for planning and construction with anticipated hazards. Climate adaptation policies based on the local effects of climate change are a new tool to communicate risk and share resources. Building codes establish minimum standards for construction, so incorporating adaptation strategies into codes ensures that the resulting structures will survive a range of uncertain futures.
Abdul-Akeem Sadiq and Jenna Tyler
Despite myriad descriptions and indicators used to define a fragile state, the international community has come to an agreement that a fragile state lacks the ability to maintain physical control of its territorial boundaries, provide basic public services, facilitate economic growth, and interact as a full member of the international community. Fragile states have historically experienced a disproportionate amount of natural disaster-related losses. For example, from 2005 to 2009, more than 50% of those impacted by a natural disaster lived in a fragile state, resulting in over $200 billion in losses. When natural disasters occur in such areas, they exacerbate already weak governance structures and further undermine their governments’ capability to respond to the crisis while simultaneously addressing challenges related to poverty and conflict. To remedy these and other complex issues inherent in fragile states, scholars are beginning to recognize the importance of investigating how fragile states can mitigate natural disaster losses through effective agency coordination and cross-sector collaboration. Agency coordination, in the context of natural disaster response, refers to the integration of facilities, equipment, personnel, and communication by public agencies for supporting incident response activities. Cross-sector collaboration refers to the sharing of information and resources by organizations in two or more sectors to achieve an outcome that cannot be produced by organizations in one sector alone. Because forecasts suggest that natural disaster-related losses will only increase in fragile states owing to population growth, urbanization, and climate change, there is a pressing need to understand the ways public organizations not only coordinate before, during, and after a natural disaster, but also how they collaborate across organizational sectors.
Rob A. DeLeo
Agenda setting describes the process through which issues are selected for consideration by a decision-making body. Among the myriad of issues policymakers can consider, few are more vexing than natural hazards. By aggregating (or threatening to aggregate) death, destruction, and economic loss, natural hazards represent a serious and persistent threat to public safety. While citizens rightfully expect policymakers to protect them, many of the policy challenges associated natural hazards fail to reach the crowded government agenda. This article reviews the literature on agenda setting and natural hazards, including the strain between preparing for emerging hazards, on the one hand, and responding to existing disasters, on the other hand. It considers the extent to which natural hazards pose distinctive difficulties during the agenda-setting process, focusing specifically on the dynamics of issue identification, problem definition, venue shopping, and interest group mobilization in natural hazard domains. It closes by suggesting a number of future avenues of agenda-setting research.
Brenden Jongman, Hessel C. Winsemius, Stuart A. Fraser, Sanne Muis, and Philip J. Ward
The flooding of rivers and coastlines is the most frequent and damaging of all natural hazards. Between 1980 and 2016, total direct damages exceeded $1.6 trillion, and at least 225,000 people lost their lives. Recent events causing major economic losses include the 2011 river flooding in Thailand ($40 billion) and the 2013 coastal floods in the United States caused by Hurricane Sandy (over $50 billion). Flooding also triggers great humanitarian challenges. The 2015 Malawi floods were the worst in the country’s history and were followed by food shortage across large parts of the country.
Flood losses are increasing rapidly in some world regions, driven by economic development in floodplains and increases in the frequency of extreme precipitation events and global sea level due to climate change. The largest increase in flood losses is seen in low-income countries, where population growth is rapid and many cities are expanding quickly. At the same time, evidence shows that adaptation to flood risk is already happening, and a large proportion of losses can be contained successfully by effective risk management strategies. Such risk management strategies may include floodplain zoning, construction and maintenance of flood defenses, reforestation of land draining into rivers, and use of early warning systems.
To reduce risk effectively, it is important to know the location and impact of potential floods under current and future social and environmental conditions. In a risk assessment, models can be used to map the flow of water over land after an intense rainfall event or storm surge (the hazard). Modeled for many different potential events, this provides estimates of potential inundation depth in flood-prone areas. Such maps can be constructed for various scenarios of climate change based on specific changes in rainfall, temperature, and sea level.
To assess the impact of the modeled hazard (e.g., cost of damage or lives lost), the potential exposure (including buildings, population, and infrastructure) must be mapped using land-use and population density data and construction information. Population growth and urban expansion can be simulated by increasing the density or extent of the urban area in the model. The effects of floods on people and different types of buildings and infrastructure are determined using a vulnerability function. This indicates the damage expected to occur to a structure or group of people as a function of flood intensity (e.g., inundation depth and flow velocity).
Potential adaptation measures such as land-use change or new flood defenses can be included in the model in order to understand how effective they may be in reducing flood risk. This way, risk assessments can demonstrate the possible approaches available to policymakers to build a less risky future.
Amr Elnashai and Hussam Mahmoud
With current rapid growth of cities and the move toward the development of both sustainable and resilient infrastructure systems, it is vital for the structural engineering community to continue to improve their knowledge in earthquake engineering to limit infrastructure damage and the associated social and economic impacts. Historically, the development of such knowledge has been accomplished through the deployment of analytical simulations and experimental testing. Experimental testing is considered the most accurate tool by which local behavior of components or global response of systems can be assessed, assuming the test setup is realistically configured and the experiment is effectively executed. However, issues of scale, equipment capacity, and availability of research funding continue to hinder full-scale testing of complete structures. On the other hand, analytical simulation software is limited to solving specific type of problems and in many cases fail to capture complex behaviors, failure modes, and collapse of structural systems. Hybrid simulation has emerged as a potentially accurate and efficient tool for the evaluation of the response of large and complex structures under earthquake loading. In hybrid (experiment-analysis) simulation, part of a structural system is experimentally represented while the rest of the structure is numerically modeled. Typically, the most critical component is physically represented. By combining a physical specimen and a numerical model, the system-level behavior can be better quantified than modeling the entire system purely analytically or testing only a component. This article discusses the use of hybrid simulation as an effective tool for the seismic evaluation of structures. First, a chronicled development of hybrid simulation is presented with an overview of some of the previously conducted studies. Second, an overview of a hybrid simulation environment is provided. Finally, a hybrid simulation application example on the response of steel frames with semi-rigid connections under earthquake excitations is presented. The simulations included a full-scale physical specimen for the experimental module of a connection, and a 2D finite element model for the analytical module. It is demonstrated that hybrid simulation is a powerful tool for advanced assessment when used with appropriate analytical and experimental realizations of the components and that semi-rigid frames are a viable option in earthquake engineering applications.
Economic resilience, in its static form, refers to utilizing remaining resources efficiently to maintain functionality of a household, business, industry, or entire economy after a disaster strikes, and, in its dynamic form, to effectively investing in repair and reconstruction to promote accelerated recovery. As such, economic resilience is oriented to implementing various post-disaster actions (tactics) to reduce business interruption (BI), in contrast to pre-disaster actions such as mitigation that are primarily oriented to preventing property damage. A number of static resilience tactics have been shown to be effective (e.g., conserving scarce inputs, finding substitutes from within and from outside the region, using inventories, and relocating activity to branch plants/offices or other sites). Efforts to measure the effectiveness of the various tactics are relatively new and aim to translate these estimates into dollar benefits, which can be juxtaposed to estimates of dollar costs of implementing the tactics. A comprehensive benefit-cost analysis can assist public- and private sector decision makers in determining the best set of resilience tactics to form an overall resilience strategy.
Bureaucratic politics, discretion, and decision-making for natural hazards governance present an important challenge of the use of autonomous bureaucratic discretion in the absence of political accountability. Understanding how these factors influence discretion and policymaking is of critical importance for natural hazards because the extent to which bureaucrats are able to make decisions means that communities will be safer in the face of disaster. But the extent to which they are held accountable for their decisions has significant implications for public risk and safety. Bureaucrats are unelected and cannot be voted out of office.
There are two significant areas that remain regarding the use of bureaucratic discretion in natural hazards policy. One key area is to consider the increasing emphasis on networked disaster governance on bureaucratic discretion and decision-making. The conventional wisdom is that networks facilitate disaster management much better than command and control approaches. However, the extent to which the use of bureaucratic discretion is important in the implementation of natural hazard policy, particularly for mitigation and preparedness, remains an open area of research.
The other key area is the influence of bureaucratic discretion and decision-making when communities learn after a disaster. The political nature of disasters and the professional expertise of public service professionals imply that in order to make communities safer, bureaucrats will have to use discretion to push forward more aggressive mitigation and preparedness policies. Bureaucratic discretion would need to be used for both political and policy purposes in order to engage in policy learning after disasters that produces a substantive change.
Margreth Keiler and Sven Fuchs
European mountain regions are diverse, from gently rolling hills to high mountain areas, and from low populated rural areas to urban regions or from communities dependent on agricultural productions to hubs of tourist industry. Communities in European mountain regions are threatened by different hazard types: for example floods, landslides, or glacial hazards, mostly in a multi-hazard environment. Due to climate change and socioeconomic developments they are challenged by emerging and spatially as well as temporally highly dynamic risks. Consequently, over decades societies in European mountain ranges developed different hazard and risk management strategies on a national to local level, which are presented below focusing on the European Alps.
Until the late 19th century, the paradigm of hazard protection was related to engineering measures, mostly implemented in the catchments, and new authorities responsible for mitigation were founded. From the 19th century, more integrative strategies became prominent, becoming manifest in the 1960s with land-use management strategies targeted at a separation of hazardous areas and areas used for settlement and economic purpose. In research and in the application, the concept of hazard mitigation was step by step replaced by the concept of risk. The concept of risk includes three components (or drivers), apart from hazard analysis also the assessment and evaluation of exposure and vulnerability; thus, it addresses in the management of risk reduction all three components. These three drivers are all dynamic, while the concept of risk itself is thus far a static approach. The dynamic of risk drivers is a result of both climate change and socioeconomic change, leading through different combinations either to an increase or a decrease in risk. Consequently, natural hazard and risk management, defined since the 21st century using the complexity paradigm, should acknowledge such dynamics. Moreover, researchers from different disciplines as well as practitioners have to meet the challenges of sustainable development in the European mountains. Thus, they should consider the effects of dynamics in risk drivers (e.g., increasing exposure, increasing vulnerability, changes in magnitude, and frequency of hazard events), and possible effects on development areas. These challenges, furthermore, can be better met in the future by concepts of risk governance, including but not limited to improved land management strategies and adaptive risk management.
Children and youth are greatly affected by disasters, and as climate instability leads to more weather-related disasters, the risks to the youngest members of societies will continue to increase. Children are more likely to live in risky places, such as floodplains, coastal areas, and earthquake zones, and more likely to be poor than other groups of people. While children and youth in industrialized countries are experiencing increased risks, the children and youth in developing countries are the most at risk to disasters.
Children and youth are vulnerable before, during, and after a disaster. In a disaster, many children and youth experience simultaneous and ongoing disruptions in their families, schooling, housing, health and access to healthcare, friendships, and other key areas of their lives. Many are at risk to separation from guardians, long-term displacement, injury, illness, and even death. In disaster planning, there is often an assumption that parents will protect their children in a disaster event, and yet children are often separated from their parents when they are at school, childcare centers, home alone, with friends, and at work. Children do not have the resources or independence to prepare for disasters, so they are often reliant on adults to make evacuation decisions, secure shelter, and provide resources. Children also may hide or have trouble articulating their distress to adults after a disaster. In the disaster aftermath, it has been found that children and youth—no matter how personally resilient—cannot fully recover without the necessary resources and social support.
Social location—such as social class, race, gender, neighborhood, resources, and networks—prior to a disaster often determines, at least in part, many of the children’s post-disaster outcomes. In other words, age intersects with many other factors. Girls, for example, are at risk to sexual violence and exploitation in some disaster aftermath situations. In addition, a child’s experience in a disaster could also be affected by language, type of housing, immigration status, legal status, and disability issues. Those living in poverty have more difficulties preparing for disasters, do not have the resources to evacuate, and live in lower quality housing that is less able to withstand a disaster. Thus, it is crucial to consider the child’s environment before and after the disaster, to realize that some children experience cumulative vulnerability, or an accumulation of risk factors, and that disasters may occur on top of other crises, such as drought, epidemics, political instability, violence, or a family crisis such as divorce or death.
Even as children and youth are vulnerable, they also demonstrate important and often unnoticed capacities, skills, and strengths, as they assist themselves and others before and after disaster strikes. Frequently, children are portrayed as helpless, fragile, passive, and powerless. But children and youth are creative social beings and active agents, and they have played important roles in preparedness activities and recovery for their families and communities. Thus, both children’s vulnerabilities and capacities in disasters should be a research and policy priority.
Gabriele Villarini and Louise Slater
Flood losses in the United States have increased dramatically over the course of the past century, averaging US$7.96 billion in damages per year for the 30-year period ranging from 1985 to 2014. In terms of human fatalities, floods are the second largest weather-related hazard in the United States, causing approximately 80 deaths per year over the same period. Given the wide-reaching impacts of flooding across the United States, the evaluation of flood-generating mechanisms and of the drivers of changing flood hazard are two areas of active research.
Flood frequency analysis has traditionally been based on statistical analyses of the observed flood distributions that rarely distinguish among physical flood-generating processes. However, recent scientific advances have shown that flood frequency distributions are often characterized by “mixed populations” arising from multiple flood-generating mechanisms, which can be challenging to disentangle. Flood events can be driven by a variety of physical mechanisms, including rain and snowmelt, frontal systems, monsoons, intense tropical cyclones, and more generic cyclonic storms.
Temporal changes in the frequency and magnitude of flooding have also been the subject of a large body of work in recent decades. The science has moved from a focus on the detection of trends and shifts in flood peak distributions towards the attribution of these changes, with particular emphasis on climatic and anthropogenic factors, including urbanization and changes in agricultural practices. A better understanding of these temporal changes in flood peak distributions, as well as of the physical flood-generating mechanisms, will enable us to move forward with the estimation of future flood design values in the context of both climatic and anthropogenic change.