1-20 of 36 Results

  • Keywords: climate change x
Clear all

Article

Disaster Epistemology, Vulnerability, and Mitigation in Guatemala  

Roberto E. Barrios

From 1976 to 2023, disaster studies experienced a revolution in the way scholars think about natural hazards and disasters. Central to this transformation was the emergence of vulnerability theory, which defines disasters as processes that unfold over long periods because of human practices that enhance the materially destructive and socially disruptive capacities of natural hazards. For researchers involved in developing this analytical perspective, the 1976 earthquake in Guatemala stands out as a prime example of the role of social forces in engendering disaster. Beyond the 1976 earthquake, a review of Guatemala’s history of disasters illuminates the intimate relationship between development practices, socioeconomic inequity, and catastrophes from the pre-Columbian period to the early 21st century. Paralleling the rise of vulnerability theory in the 1970s was the growing interest of disaster scholars in the methodological potential of catastrophes to reveal social structures (e.g., kinship organization) and fault lines (e.g., class and racial structures) that are not readily apparent in times of “normalcy.” Moreover, this interest in the revelatory qualities of disasters was accompanied by a number of hypotheses concerning the relationship between disasters and social change. Once again, Guatemala has offered a number of case studies that illustrate how disasters allow researchers to see social structures, inequities, and contradictions and have shed light on why some disasters are conducive to progressive social change while others are not. Specifically, the case of Guatemala demands social scientists understand disaster vulnerability and the transformative potential of disasters within the broader global political–economic networks of colonial and postcolonial extraction and exploitation. As the 21st century progresses, Guatemala struggles with the local particularities of global disasters. Central America is the tropical region that stands to be most affected by anthropogenic climate change, yet the country’s national government has not implemented the hazard mitigation, urban planning, and inequity reduction programs necessary to counteract these effects. From 2015 to 2023, climate change–related droughts and floods displaced thousands of subsistence farmers, many of whom chose to migrate internationally in search of better livelihoods. Similarly, the COVID-19 pandemic impacted a country with a fragmented and critically underfunded health care system and deeply entrenched inequities between urban and rural and Indigenous and non-Indigenous populations. As a result, Guatemala’s excess mortality rate during the most acute years of the pandemic (2020 and 2021) more than doubled that of Costa Rica, the Central American nation that was best prepared to confront the global health crisis. Despite the notable role of the 1976 earthquake as a classic example of vulnerability theory and the role disasters have played in inciting socio-political upheavals and change, disaster social science research and disaster risk reduction remain poorly developed in Guatemala.

Article

Climate Change as a Transboundary Policymaking Natural Hazards Problem  

Elizabeth Albright

Throughout the world, major climate-related catastrophic events have devastated lives and livelihoods. These events are predicted to increase in frequency and intensity across the globe, as greenhouse gas emissions continue to accumulate in our atmosphere. The causes and consequences of these disasters are not constrained to geographic and political boundaries, or even temporal scales, increasing the complexity of their management. Differences in cultures, governance and policy processes often occur among jurisdictions in a transboundary setting, whether adjacent nations that are exposed to the same transboundary hazard or across municipalities located within the same political jurisdiction. Political institutions and processes may vary across jurisdictions in a region, presenting challenges to cooperation and coordination of risk management. With shifting climates, risks from climate-related natural hazards are in constant flux, increasing the difficulty of making predictions about and governing these risks. Further, different groups of individuals may be exposed to the same climate hazard, but that exposure may affect these groups in unique ways. Managing climate change as a transboundary natural hazard may mandate a shift from a focus on individual climate risks to developing capacity to encourage learning from and adaptation to a diversity of climatic risks that span boundaries. Potential barriers to adaptation to climate risks must not be considered individually but rather as a part of a more dynamic system in which multiple barriers may interact, impeding effective management. Greater coordination horizontally, for example through networks linking cities, and vertically, across multiple levels of governance (e.g., local, regional, national, global), may aid in the development of increased capacity to deal with these transboundary risks. Greater public engagement in management of risks from climate change hazards, both in risk mitigation and post-hazard recovery, could increase local-level capacity to adapt to these hazards.

Article

Modeling Tropical Cyclones in a Changing Climate  

Enrico Scoccimarro

Tropical cyclones (TCs) in their most intense expression (hurricanes or typhoons) are the main natural hazards known to humankind. The impressive socioeconomic consequences for countries dealing with TCs make our ability to model these organized convective structures a key issue to better understanding their nature and their interaction with the climate system. The destructive effects of TCs are mainly caused by three factors: strong wind, storm surge, and extreme precipitation. These TC-induced effects contribute to the annual worldwide damage of the order of billions of dollars and a death toll of thousands of people. Together with the development of tools able to simulate TCs, an accurate estimate of the impact of global warming on TC activity is thus not only of academic interest but also has important implications from a societal and economic point of view. The aim of this article is to provide a description of the TC modeling implementations available to investigate present and future climate scenarios. The two main approaches to dynamically model TCs under a climate perspective are through hurricane models and climate models. Both classes of models evaluate the numerical equations governing the climate system. A hurricane model is an objective tool, designed to simulate the behavior of a tropical cyclone representing the detailed time evolution of the vortex. Considering the global scale, a climate model can be an atmosphere (or ocean)-only general circulation model (GCM) or a fully coupled general circulation model (CGCM). To improve the ability of a climate model in representing small-scale features, instead of a general circulation model, a regional model (RM) can be used: this approach makes it possible to increase the spatial resolution, reducing the extension of the domain considered. In order to be able to represent the tropical cyclone structure, a climate model needs a sufficiently high horizontal resolution (of the order of tens of kilometers) leading to the usage of a great deal of computational power. Both tools can be used to evaluate TC behavior under different climate conditions. The added value of a climate model is its ability to represent the interplay of TCs with the climate system, namely two-way relationships with both atmosphere and ocean dynamics and thermodynamics. In particular, CGCMs are able to take into account the well-known feedback between atmosphere and ocean components induced by TC activity and also the TC–related remote impacts on large-scale atmospheric circulation. The science surrounding TCs has developed in parallel with the increasing complexity of the mentioned tools, both in terms of progress in explaining the physical processes involved and the increased availability of computational power. Many climate research groups around the world, dealing with such numerical models, continuously provide data sets to the scientific community, feeding this branch of climate change science.

Article

Assessment and Adaptation to Climate Change-Related Flood Risks  

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.

Article

Social Capital and Natural Hazards Governance  

Daniel P. Aldrich, Michelle A. Meyer, and Courtney M. Page-Tan

The impact of disasters continues to grow in the early 21st century, as extreme weather events become more frequent and population density in vulnerable coastal and inland cities increases. Against this backdrop of risk, decision-makers persist in focusing primarily on structural measures to reduce losses centered on physical infrastructure such as berms, seawalls, retrofitted buildings, and levees. Yet a growing body of research emphasizes that strengthening social infrastructure, not just physical infrastructure, serves as a cost-effective way to improve the ability of communities to withstand and rebound from disasters. Three distinct kinds of social connections, including bonding, bridging, and linking social ties, support resilience through increasing the provision of emergency information, mutual aid, and collective action within communities to address natural hazards before, during, and after disaster events. Investing in social capital fosters community resilience that transcends natural hazards and positively affects collective governance and community health. Social capital has a long history in social science research and scholarship, particularly in how it has grown within various disciplines. Broadly, the term describes how social ties generate norms of reciprocity and trust, allow collective action, build solidarity, and foster information and resource flows among people. From education to crime, social capital has been shown to have positive impacts on individual and community outcomes, and research in natural hazards has similarly shown positive outcomes for individual and community resilience. Social capital also can foster negative outcomes, including exclusionary practices, corruption, and increased inequality. Understanding which types of social capital are most useful for increasing resilience is important to move the natural hazards field forward. Many questions about social capital and natural hazards remain, at best, partially answered. Do different types of social capital matter at different stages of disaster—e.g., mitigation, preparedness, response, and recovery? How do social capital’s effects vary across cultural contexts and stratified groups? What measures of social capital are available to practitioners and scholars? What actions are available to decision-makers seeking to invest in the social infrastructure of communities vulnerable to natural hazards? Which programs and interventions have shown merit through field tests? What outcomes can decision-makers anticipate with these investments? Where can scholars find data sets on resilience and social capital? The current state of knowledge about social capital in disaster resilience provides guidance about supporting communities toward more resilience.

Article

Gender Mainstreaming and Climate Change  

Margaret Alston

Women and girls are disproportionately impacted by climate change, not because of innate characteristics but as a result of the social structures and cultural norms that shape gender inequalities. Feminist activists and transnational organizations continue to voice their concerns regarding the need for greater attention to gender inequalities in the context of climate change. Gender mainstreaming is a policy process designed to address the gendered consequences of any planned actions—the ultimate aim being to achieve gender equality. Gender mainstreaming emerged in the late 1990s at the Beijing Women’s Conference as a result of the frustrations of feminist activists and international nongovernmental organizations about the lack of attention to gender equality. Yet its implementation has been hampered both by a lack of vision as to its purpose and by ongoing tensions, particularly between those who espouse equality and those who support the mainstream. This has led to resistance to gender mainstreaming within departments and units that are charged with its implementation, and indeed a reluctance of key players to commit to gender equality. Yet there is still strong support for the original feminist intent from activists and researchers addressing the impacts of climate change. The transformational potential of gender mainstreaming is still viewed as a process that could address and challenge gender inequalities in the context of increasing climate challenges. However, there are barriers that must be overcome for the transformational potential of gender mainstreaming to be realized. These include equating climate justice with gender justice, ensuring that the radical feminist intent of gender mainstreaming is not co-opted by the neoliberal agenda of maximizing economic development over gender equality and women’s empowerment, and ensuring that organizations tasked with facilitating gender mainstreaming not only understand its intent but also address gender inequalities within their own organizational structures and practices.

Article

Masculinities and Disaster  

Scott McKinnon

Gender plays a role in all phases of the disaster cycle, from the lived experience of disaster survivors to the development of disaster risk reduction (DRR) policy and practice. Early research into the entanglement of gender and disaster revealed how women are made more vulnerable to disaster impacts by sexist and misogynist social structures. Researchers have since identified women’s central roles in building disaster resilience and aiding community recovery. Feminist scholarship has been highly influential in disasters research, prompting consideration of how intersecting social characteristics, including gender, sexuality, race, class, and bodily ability each contributes to the social construction of disaster. Drawing on work in the field of critical men’s studies, a small but growing body of research has engaged with the role of gender in men’s disaster experiences, as well as how hegemonic masculinity shapes emergency management practice, constructs widely understood disaster narratives, and influences the development of DRR policy, including policies related to the crisis of climate change. Rather than a fixed identity, hegemonic masculinity operates as a culturally dominant ideal to which men and boys are expected to strive. It is spatially constituted and relational, often defined by attributes including physical strength, bravery, and confidence. To date, the most substantial focus of research into masculinity and disasters relates to the lived and bodily experience of men impacted by wildfire. Australian researchers in particular have identified ways in which hegemonic ideals increase the disaster vulnerability of men, who feel pressure to act with bravery and to exhibit emotional and physical strength in conditions of extreme danger. Expectations of stoicism and courage equally impact men’s recovery from disaster, potentially limiting opportunities to access necessary support systems, particularly in relation to mental health and emotional well-being. Hegemonic masculine ideals similarly impact the experiences of frontline emergency workers. Emergency management workplaces are often constructed as masculine spaces, encouraging high-risk behaviors by male workers, and limiting opportunities for participation by people of other genders. Male dominance in the leadership of emergency management organizations also impacts policy and practice, including in the distribution of resources and in attentiveness to the role of gender in the disaster experiences of many survivors. Dominant disaster narratives, as seen in movies and the news media, contribute to the idea that disaster landscapes are ideal places for the performance of hegemonic masculine identities. Male voices dominate in media reporting of disasters, often leaving invisible the experiences of other people, with consequences for how disasters are understood by the wider public. Common tropes in Hollywood cinema similarly depict disasters as masculine events, in which brave cisgender men protect vulnerable cisgender women, with people of other genders entirely invisible. Identifying and addressing the role of masculinities in disaster is increasingly important within the crisis of global heating. As climate change increases the frequency and intensity of disasters, new ways of engaging with the environment and constructing DRR policy has become more urgent. Research in this field offers a critical baseline by which to move beyond binary gender definitions and to address damaging masculine ideals that ultimately harm the environment and people of all genders.

Article

Assessment Principles for Glacier and Permafrost Hazards in Mountain Regions  

Simon Allen, Holger Frey, Wilfried Haeberli, Christian Huggel, Marta Chiarle, and Marten Geertsema

Glacier and permafrost hazards in cold mountain regions encompass various flood and mass movement processes that are strongly affected by rapid and cumulative climate-induced changes in the alpine cryosphere. These processes are characterized by a range of spatial and temporal dimensions, from small volume icefalls and rockfalls that present a frequent but localized danger to less frequent but large magnitude process chains that can threaten people and infrastructure located far downstream. Glacial lake outburst floods (GLOFs) have proven particularly devastating, accounting for the most far-reaching disasters in high mountain regions globally. Comprehensive assessments of glacier and permafrost hazards define two core components (or outcomes): 1. Susceptibility and stability assessment: Identifies likelihood and origin of an event based on analyses of wide-ranging triggering and conditioning factors driven by interlinking atmospheric, cryospheric, geological, geomorphological, and hydrological processes. 2. Hazard mapping: Identifies the potential impact on downslope and downstream areas through a combination of process modeling and field mapping that provides the scientific basis for decision making and planning. Glacier and permafrost hazards gained prominence around the mid-20th century, especially following a series of major disasters in the Peruvian Andes, Alaska, and the Swiss Alps. At that time, related hazard assessments were reactionary and event-focused, aiming to understand the causes of the disasters and to reduce ongoing threats to communities. These disasters and others that followed, such as Kolka Karmadon in 2002, established the fundamental need to consider complex geosystems and cascading processes with their cumulative downstream impacts as one of the distinguishing principles of integrative glacier and permafrost hazard assessment. The widespread availability of satellite imagery enables a preemptive approach to hazard assessment, beginning with regional scale first-order susceptibility and hazard assessment and modeling that provide a first indication of possible unstable slopes or dangerous lakes and related cascading processes. Detailed field investigations and scenario-based hazard mapping can then be targeted to high-priority areas. In view of the rapidly changing mountain environment, leading beyond historical precedence, there is a clear need for future-oriented scenarios to be integrated into the hazard assessment that consider, for example, the threat from new lakes that are projected to emerge in a deglaciating landscape. In particular, low-probability events with extreme magnitudes are a challenge for authorities to plan for, but such events can be appropriately considered as a worst-case scenario in a comprehensive, forward-looking, multiscenario hazard assessment.

Article

Glacier Retreat and Glacial Lake Outburst Floods (GLOFs)  

Adam Emmer

Glacier retreat is considered to be one of the most obvious manifestations of recent and ongoing climate change in the majority of glacierized alpine and high-latitude regions throughout the world. Glacier retreat itself is both directly and indirectly connected to the various interrelated geomorphological/hydrological processes and changes in hydrological regimes. Various types of slope movements and the formation and evolution of lakes are observed in recently deglaciated areas. These are most commonly glacial lakes (ice-dammed, bedrock-dammed, or moraine-dammed lakes). “Glacial lake outburst flood” (GLOF) is a phrase used to describe a sudden release of a significant amount of water retained in a glacial lake, irrespective of the cause. GLOFs are characterized by extreme peak discharges, often several times in excess of the maximum discharges of hydrometeorologically induced floods, with an exceptional erosion/transport potential; therefore, they can turn into flow-type movements (e.g., GLOF-induced debris flows). Some of the Late Pleistocene lake outburst floods are ranked among the largest reconstructed floods, with peak discharges of up to 107 m3/s and significant continental-scale geomorphic impacts. They are also considered capable of influencing global climate by releasing extremely high amounts of cold freshwater into the ocean. Lake outburst floods associated with recent (i.e., post-Little Ice Age) glacier retreat have become a widely studied topic from the perspective of the hazards and risks they pose to human society, and the possibility that they are driven by anthropogenic climate change. Despite apparent regional differences in triggers (causes) and subsequent mechanisms of lake outburst floods, rapid slope movement into lakes, producing displacement waves leading to dam overtopping and eventually dam failure, is documented most frequently, being directly (ice avalanche) and indirectly (slope movement in recently deglaciated areas) related to glacial activity and glacier retreat. Glacier retreat and the occurrence of GLOFs are, therefore, closely tied, because glacier retreat is connected to: (a) the formation of new, and the evolution of existing, lakes; and (b) triggers of lake outburst floods (slope movements).

Article

Natural Hazards and Their Governance in Sub-Saharan Africa  

Dewald van Niekerk and Livhuwani David Nemakonde

The sub-Saharan Africa (SSA) region, along with the rest of the African continent, is prone to a wide variety of natural hazards. Most of these hazards and the associated disasters are relatively silent and insidious, encroaching on life and livelihoods, increasing social, economic, and environmental vulnerability even to moderate events. With the majority of SSA’s disasters being of hydrometeorological origin, climate change through an increase in the frequency and magnitude of extreme weather events is likely to exacerbate the situation. Whereas a number of countries in SSA face significant governance challenges to effectively respond to disasters and manage risk reduction measures, considerable progress has been made since the early 2000s in terms of policies, strategies, and/or institutional mechanisms to advance disaster risk reduction and disaster risk management. As such, most countries in SSA have developed/reviewed policies, strategies, and plans and put in place institutions with dedicated staffs and resources for natural hazard management. However, the lack of financial backing, limited skills, lack of coordination among sectors, weak political leadership, inadequate communication, and shallow natural hazard risk assessment, hinders effective natural hazard management in SSA. The focus here is on the governance of natural hazards in the sub-Saharan Africa region, and an outline of SSA’s natural hazard profile is presented. Climate change is increasing the frequency and magnitude of extreme weather events, thus influencing the occurrence of natural hazards in this region. Also emphasized are good practices in natural hazard governance, and SSA’s success stories are described. Finally, recommendations on governance arrangements for effective implementation of disaster risk reduction initiatives and measures are provided.

Article

Natural Hazards Governance in Nigeria  

Steve I. Onu

Nigeria, like many other countries in sub–Saharan Africa, is exposed to natural hazards and disaster events, the most prominent being soil and coastal erosion, flooding, desertification, drought, air pollution as a result of gas flaring, heat waves, deforestation, and soil degradation due to oil spillage. These events have caused serious disasters across the country. In the southeast region, flooding and gully erosion have led to the displacement of communities. In the Niger Delta region, oil exploration has destroyed the mangrove forests as well as the natural habitat for fishes and other aquatic species and flora. In northern Nigeria, desert encroachment, deforestation, and drought have adversely affected agricultural production, thereby threatening national food security. The federal government, through its agencies, has produced and adopted policies and enacted laws and regulations geared toward containing the disastrous effects of natural hazards on the environment. The federal government collaborates with international organizations, such as the World Bank, International Atomic Energy Agency (IAEA), International Fund for Agricultural Development (IFAD), Center for Infectious Disease Research (CIDR), United Nations Industrial Development Organization (UNIDO), United Nations Environment Programme (UNEP), United Nations High Commission for Refugees UNHCR, and non-governmental organizations (NGOs), to address disaster-related problems induced by natural hazards. However, government efforts have not yielded the desired results due to interagency conflicts, corruption, low political will, and lack of manpower capacity for disaster management. There is a need for a good governance system for natural hazards prevention and reduction in the country. This will require inter-agency synergy, increased funding of agencies, capacity building, and public awareness/participation.

Article

Climate Change Adaptation in New Zealand  

Paul Schneider and Bruce Glavovic

Coastal hazard risk is compounded by climate change. The promise and prospects of adaptation to escalating coastal hazard risk is fraught, even in a country like New Zealand that has laudable provisions for local authorities to be proactive in adapting to climate change. Continuing property development in some low-lying coastal areas is resulting in contestation and maladaptation. The resistance of some local authorities to do the inevitable and make long-term planning decisions in the face of amplifying risk can be linked to adaptation barriers. What can be done to overcome barriers and facilitate adaptation? Is transformation of the current mismatch between short-term planning and development aspirations, long-term societal goals, dynamic coastal processes and well-intended legislation and policy goals even possible? What can we learn from adaptation failures? In the face of compelling evidence and an enabling institutional framework, why is it that some coastal communities fail to prepare for the future? We shed light on such questions based on a long-term study of experience in New Zealand’s Coromandel Peninsula. We focus on the overarching question: Why is adaptation so challenging; and why are some coastal communities locked- into maladaptive pathways? We focus on the influence of a short-term decision-making focus of the problem of a low level of understanding and, following from this, the prioritization of protective works to combat erosion. Further, we draw attention to a major storm impact and the failure to turn this window of opportunity to a shift away from business as usual. Through the exploration of key stakeholder insights, the findings from the literature are reinforced and put into local context thus making the otherwise abstract barriers locally relevant. Matching and aligning adaptation theory with local reality can assist in advancing inquiry and policy practice to govern complex adaptation challenges.

Article

The Impact of Moisture and Temperature on Human Health in Heat Waves  

Michael Wehner, Federico Castillo, and Dáithí Stone

Extremely high air temperatures are uncomfortable for everyone. For some segments of the population, they can be deadly. Both the physical and societal aspects of intense heat waves in a changing climate warrant close study. The large-scale meteorological patterns leading to such events lay the framework for understanding their underlying causal mechanisms, while several methods of quantifying the combination of heat and humidity can be used to determine when these patterns result in stressful conditions. We examine four historic heat waves as case studies to illustrate differences in the structure of heat waves and the variety of effects of extreme heat on humans, which are characterized in terms of demographic, geographic, and socioeconomic impacts, including mortality and economic ramifications. Weather station data and climate model projections for the future point to an increase in the frequency and intensity of extreme heat waves as the overall climate gets warmer. Changes in the radiative energy balance of the planet are the principal culprit behind this increase. Quantifying changes in the statistics of extreme heat waves allows for examination of changes in their potential contribution to human health risk. Large-scale mortality during heat waves always occurs within a context of other factors, including public health policy, rural and urban management and planning, and cultural practices. Consequently, the impacts of heat waves can be reduced, and may in many places be manageable into the future, through implementation of such measures as public health warning systems, effective land management, penetration of air conditioning, and increased monitoring of vulnerable or exposed individuals. Given the potential for severe impacts of the more intense heat waves that are virtually certain to occur in the warmer future, it is critical that both the physical and social sciences be considered together to enable society to adapt to these conditions.

Article

Persistent Homology for Land Cover Change Detection  

Djamel Bouchaffra and Faycal Ykhlef

The need for environmental protection, monitoring, and security is increasing, and land cover change detection (LCCD) can aid in the valuation of burned areas, the study of shifting cultivation, the monitoring of pollution, the assessment of deforestation, and the analysis of desertification, urban growth, and climate change. Because of the imminent need and the availability of data repositories, numerous mathematical models have been devised for change detection. Given a sample of remotely sensed images from the same region acquired at different dates, the models investigate if a region has undergone change. Even if there is no substantial advantage to using pixel-based classification over object-based classification, a pixel-based change detection approach is often adopted. A pixel can encompass a large region, and it is imperative to determine whether this pixel (input) has changed or not. A changed image is compared to the available ground truth image for pixel-based performance evaluation. Some existing change detection systems do not take into account reversible changes due to seasonal weather effects. In other words, when snow falls in a region, the land cover is not considered as a change because it is seasonal (reversible). Some approaches exploit time series of Landsat images, which are based on the Normalized Difference Vegetation Index technique. Others evaluate built-up expansion to assess urban morphology changes using an unsupervised approach that relies on labels clustering. Change detection methods have also been applied to the field of disaster management using object-oriented image classification. Some methodologies are based on spectral mixture analysis. Other techniques invoke a similarity measure based on the evolution of the local statistics of the image between two dates for vegetation LCCD. Probabilistic approaches based on maximum entropy have been applied to vegetation and forest areas, such as Hustai National Park in Mongolia. Researchers in this field have proposed an LCCD scheme based on a feed-forward neural network using backpropagation for training. This paper invokes the new concept of homology theory, a subfield of algebraic topology. Homology theory is incorporated within a Structural Hidden Markov Model.

Article

Linking Hazard Vulnerability, Risk Reduction, and Adaptation  

Jörn Birkmann and Joanna M. McMillan

The concepts of vulnerability, disaster risk reduction and climate change adaptation are interlinked. Risk reduction requires a focus not just on the hazards themselves or on the people and structures exposed to hazards but on the vulnerability of those exposed. Vulnerability helps with the identification of root causes that make people or structures susceptible to being affected by natural and climate-related hazards. It is therefore an essential component of reducing risk of disasters and of adapting to climate change. The need to better assess and acknowledge vulnerability has been recognized by several communities of thought and practice, including the Disaster Risk Reduction (DRR) and Climate Change Adaptation (CCA) communities. The concept of vulnerability was introduced during the 1980s as a way to better understand the differential consequences of similar hazard events and differential impacts of climate change on different societies or social groups and physical structures. Since then, the concept gradually became an integral part of discourses around disaster risk reduction and climate change adaptation. Although the history of the emergence of vulnerability concepts and the different perspectives of these communities mean the way they frame vulnerability differs, the academic discourse has reached wide agreement that risk—and actual harm and losses—are not just caused by physical events apparently out of human control but primarily by what is exposed and vulnerable to those events. In the international policy arena, vulnerability, risk, and adaptation concepts are now integrated into the global agenda on sustainable development, disaster risk reduction, and climate change. In the context of international development projects and financial aid, the terms and concepts are increasingly used and applied. However, there is still too little focus on addressing underlying vulnerabilities.

Article

Planning Systems for Natural Hazard Risk Reduction  

James C. Schwab

Planning systems are essentially a layer of guidance or legal requirements that sit atop plans of any type at any governmental level at or below the source of that guidance. In the case of natural hazard risk reduction, they involve rules or laws dealing with plans to reduce loss of life or property from such events. In much of the world, this is either unexplored territory or the frontier of public planning; very little of what exists in this realm predates the 1980s, although one can find earlier roots of the public discussion behind such systems. That said, the evolution of such systems in 21st century has been fairly rapid, at least in those nations with the resources and technical capacity to pursue the subject. Driven largely by substantial increases in disaster losses and growing concern about worldwide impacts of climate change, research, technology, and lessons from practice have grown apace. However, that progress has been uneven and subject to inequities in resources and governmental capacity.

Article

Climate Adaptation Governance in Pakistan  

Syed-Muhammad Ali, Akhtar Naeem Khan, and Hamna Shakeel

Climate change is one of the greatest threats to the security of water, food, and energy in Pakistan. Pakistan has seen increased visibility of direct and indirect impacts of climate change since the early 1990s. Pakistan’s government achieved a milestone in 2012 when the first National Climate Change Policy (NCCP) was proposed. In response to dynamic climate trends, it provided a broad set of adaptation measures for vulnerable sectors such as power, food, water, and health. In 2014, a more precise follow-up framework was developed which proposed strategies to achieve the objectives of the NCCP. The government is also cooperating with national and international organizations and societies to make vulnerable sectors and local communities resilient against water shortages, flash floods, cyclones, and temperature extremes. Analysis of the existing state of adaptation actions and systems exposes several deficiencies. There is a huge knowledge gap between researchers and policymakers which needs to be bridged. Stakeholders, local communities, and experts from relevant fields need to be involved in the process of policy making for the development of a comprehensive adaptation plan. Educational and research institutes in Pakistan are deficient in expertise and modern tools and technologies for predicting future climatic trends and the risks they pose to various sectors of the country. Lack of awareness in the general public, related to climate change and associated risks, is also an obstacle in developing climate-resilient communities. The government of Pakistan is giving due importance to the development of policies and capacity building of relevant implementing departments and research institutes. However, there is still a need for a strong enforcement body at the national, provincial, and municipal levels to successfully implement government strategies.

Article

Lessons on Risk Governance From the UNISDR Experience  

Sálvano Briceño

In the context of this article, risk governance addresses the ways and means—or institutional framework—to lead and manage the issue of risk related to natural phenomena, events, or hazards, also referred to popularly, although incorrectly, as “natural disasters.” At the present time, risk related to natural phenomena includes a major focus on the issue of climate change with which it is intimately connected, climate change being a major source of risk. To lead involves mainly defining policies and proposing legislation, hence proposing goals, conducting, promoting, orienting, providing a vision—namely, reducing the loss of lives and livelihoods as part of sustainable development—also, raising awareness and educating on the topic and addressing the ethical perspective that motivates and facilitates engagement by citizens. To manage involves, among other things, proposing organizational and technical arrangements, as well as regulations allowing the implementation of policies and legislation. Also, it involves monitoring and supervising such implementation to draw further lessons to periodically enhance the policies, legislation, regulations, and organizational and technical arrangements. UNISDR (now known as UNDRR) was established in 2000 to promote and facilitate risk reduction, becoming in a few years one of the main promoters of risk governance in the world and the main global advocate from within the United Nations system. It was an honor to serve as the first director of the UNISDR (2001–2011). A first lesson to be drawn from this experience was the need to identify, understand, and address the obstacles not allowing the implementation of what seems to be obvious to the scientific community but of difficult implementation by governments, private sector, and civil society; and alternatively, the reasons for shortcomings and weaknesses in risk governance. A second lesson identified was that risk related to natural phenomena also provides lessons for governance related to other types of risk in society—environmental, financial, health, security, and so on, each a separate and specialized topic, sharing, however, common risk governance approaches. A third lesson was the relevance of understanding leadership and management as essential components in governance. Drawing lessons on one’s own experience is always risky as it involves some subjectivity in the analysis. In the article, the aim has, nonetheless, been at the utmost objectivity on the essential learnings in having conducted the United Nations International Strategy for Disaster Reduction—UNISDR—from 2001 to around 2009 when leading and managing was shared with another manager, as I prepared for retirement in 2011. Additional lessons are identified, including those related to risk governance as it is academically conceived, hence, what risk governance includes and how it has been implemented by different international, regional, national, and local authorities. Secondly, I identify those lessons related to the experience of leading and managing an organization focused on disaster risk at the international level and in the context of the United Nations system.

Article

Impact of Climate Change on Flood Factors and Extent of Damages in the Hindu Kush Region  

Atta-ur Rahman, Shakeel Mahmood, Mohammad Dawood, Ghani Rahman, and Fang Chen

This chapter analyzes the impacts of climate change on flood factors and extent of associated damages in the Hindu Kush (HK) region. HK mountains system is located in the west of the Himalayas and Karakorum. It is the greatest watershed of the River Kabul, River Chitral, River Panjkora, and River Swat in the eastern Hindu Kush and River Amu in western Hindu Kush. The Hindu Kush system hosts numerous glaciers, snow-clad mountains, and fertile river valleys; it also supports large populations and provides year-round water to recharge streams and rivers. The study region is vulnerable to a wide range of hazards including floods, earthquakes, landslides, desertification, and drought. Flash floods and riverine floods are the deadliest extreme hydro-meteorological events. The upper reaches experience characteristics of flash flooding, whereas the lower reach is where river floods occur. Flash floods are more destructive and sudden. Almost every year in summer, monsoonal rainfall and high temperature join hands with heavy melting of glaciers and snow accelerating discharge in the river system. In the face of climate change, a significant correlation between rainfall patterns, trends in temperature, and resultant peaks in river discharge have been recorded. A rising trend was found in temperature, which leads to early and rapid melting of glaciers and snow in the headwater region. The analysis reveals that during the past three decades, radical changes in the behavior of numerous valley glaciers have been noted. In addition, the spatial and temporal scales of violent weather events have been growing, since the 1980s. Such changes in water regimes including the frequent but substantial increase in heavy precipitation events and rapid melting of snow in the headwater region, siltation in active channels, excessive deforestation, and human encroachments onto the active flood channel have further escalated the flooding events. The HK region is beyond the reach of existing weather RADAR network, and hence forecasting and early warning is ineffective. Here, almost every year, the floods cause damages to infrastructure, scarce farmland, and sources of livelihood.

Article

Permafrost-Related Geohazards in Cold Russian Regions  

Dmitry Sergeev

Permafrost, or perennially frozen ground, and the processes linked to the water phase change in ground-pore media are sources of specific dangers to infrastructure and economic activity in cold mountainous regions. Additionally, conventional natural hazards (such as earthquakes, floods, and landslides) assume special characteristics in permafrost territories. Permafrost hazards are created under two conditions. The first is a location with ice-bounded or water-saturated ground, in which the large amount of ice leads to potentially intensive processes of surface settlement or frost heaving. The second is linked with external, natural, and human-made disturbances that change the heat-exchange conditions. The places where ice-bounded ground meets areas that are subject to effective disturbances are the focus of hazard mapping and risk evaluation. The fundamentals of geohazard evaluation and geohazard mapping in permafrost regions were originally developed by Gunnar Beskow, Vladimir Kudryavtsev, Troy Péwé, Oscar Ferrians, Jerry Brown, and other American, European, and Soviet authors from 1940s to the 1980s. Modern knowledge of permafrost hazards was significantly enriched by the publication of Russian book called Permafrost Hazards, part of the six-volume series Natural Hazards in Russia (2000). The book describes, analyses, and evaluates permafrost-related hazards and includes methods for their modeling and mapping. Simultaneous work on permafrost hazard evaluation continued in different countries with the active support of the International Permafrost Association. Prominent contributions during the new period of investigation were published by Drozdov, Clarke, Kääb, Pavlov, Koff and several other thematic groups of researchers. The importance of common international works became evident. The international project RiskNat: A Cross-Border European Project Taking into Account Permafrost-Related Hazards was developed as a new phenomenon in scientific development. The intensive economic development in China presented new challenges for linear transportation routes and hydrologic infrastructures. A study of active fault lines and geological hazards along the Golmud–Lhasa Railway across the Tibetan plateau is a good example of the achievements by Chinese scientists. The method for evaluating the permafrost hazards was based on survey data, monitoring data, and modeling results. The survey data reflected the current environmental conditions, and they are usually shown on a permafrost map. The monitoring data are helpful in understanding the current tendencies of permafrost evolution in different landscapes and regions. The modeling data provided a permafrost forecast that takes climate change and its impact on humans into account. The International Conference on Permafrost in 2016, in Potsdam, Germany, demonstrated the new horizons of conventional and special permafrost mapping in offshore and continental areas. Permafrost hazards concern large and diverse aspects of human life. It is necessary to expand the approach to this problem from geology to also include geography, biology, social sciences, engineering, and other spheres of competencies in order to synthesize local and regional information. The relevance of this branch of science grows with taking into account climate change and the growing number of natural disasters.