Sin categoría

By Silvia De Angeli , posted on the blog of the Natural Hazards (NH) Division of the European Geosciences Union (EGU)Read the original article here Photo credit, from top left to bottom right: Pamela Trisolino (via Imaggeo), Michiel Baatsen (via Imaggeo), Stefan Doerr (via Imaggeo), Dimitri Defrance (via Imaggeo), Katja Bigge (via Imaggeo), Babak Hejrani (via Imaggeo), Elias Sch (via Pixabay) and Dan Killam (via Imaggeo). With the Natural Hazards 101 series, we mean to bring our readers closer to the terminology often used in the field of natural hazards, but that may not be so familiar. In the first episode of the series, we focused on the definition of hazard and natural hazard. We moved then to the concepts of risk, disaster risk management, and the forecasting and modelling of natural hazards. In this episode, we will explore the meaning of multi-hazards and multi-hazard risk. According to UNDRR [1], the multi-hazard concept refers to “(1) the selection of multiple major hazards that the country faces, and (2) the specific contexts where hazardous events may occur simultaneously, cascadingly or cumulatively over time, and taking into account the potential interrelated effects.” These definitions of multi-hazard represent two major categories in which multi-hazard approaches can be classified: (i) independent multi-hazards approaches, where single hazards are just overlayed and treated as independent phenomena, and (ii) approaches that consider multiple hazards and their potential interactions. Single hazard and independent multi-hazards approaches could potentially underestimate the risk leading to inadequate disaster risk reduction measures. Although more challenging and demanding, the approaches that consider multiple hazards and their potential interactions are better able to capture the real risk in many areas of the world. The interactions between hazards are diverse and complicated, which leads to differences in the literature regarding the identification and classification of these interactions (see for example, [2, 3,4]). However, it is possible to identify some basic mechanisms of interaction: Triggering is when one hazard directly triggers another, generating what is called a “domino effect” or “triggering mechanism” among hazards. This is the case of the Great East Japan Earthquake that struck in the Pacific Ocean off the northeast coast of Japan’s Honshu island in 2011 and triggered a massive tsunami that flooded more than 200 square miles of coastal land [5]. Influence is when one hazard can influence another hazard, for example, changing its probability of occurrence or magnitude, without acting as a trigger. A typical example is the removal of protective forest by an avalanche in winter that leads to higher frequency and magnitude of rock falls during summer [6]. Coincidence is when hazards occur in the same place simultaneously independently from the causal dependence among them. For example, the volcanic eruption of Mount Pinatubo in the Philippines in 1991 coincided with the intense rainfalls caused by the passage of Typhoon Yunya [2]. In contrast to single hazard events, the assessment of multiple hazards and their relationships poses a series of challenges in each step of the risk analysis: from the assessment of the hazard level to the vulnerability analysis and the resultant risk level. Indeed, hazard dependencies may influence the overall hazard level and the vulnerability of elements at risk. As an emerging focus of research and interest, the multi-hazard risk still lacks a common and standard definition and glossary among the different communities [7]. Some authors distinguish between ‘multi-hazard risk’ and ‘multi-risk’. Kappes et al. [6] define multi-hazard risk as a risk evaluation that considers the impact of multiple hazards, and multi-risk as related to the assessment of multiple risks such as economic, ecological, social, etc. Other authors [8, 9] use the term multi-risk to define an approach that determines the whole risk from several hazards, accounting for possible hazards and vulnerability interactions entailing both a multi-hazard and multi-vulnerability perspective. The concept of multi-vulnerability refers to “the ensemble of interconnected and dynamic vulnerabilities among different exposed elements” [9]. For physical vulnerability assessments, multi-vulnerability mainly refers to the development of multi-hazard damage or fragility functions (for example, [10]), able to model the damage caused by simultaneous or subsequent hazards on the same exposed element. Multi-hazard risk (or multi-risk) approaches are crucial to define successful disaster risk reduction measures. Traditionally, disaster risk reduction measures are implemented to decrease the risk of a single hazard type despite their potential of having unwanted effects on other hazard typologies. These potentially negative effects between measures are defined by de Ruiter et al. [11] as ‘asynergies’. For example, building on stilts is an often-used measure to decrease a building’s flood vulnerability; however, it simultaneously increases its earthquake vulnerability [11]. Multi-hazard risk approaches allow improving the understanding of these asynergies, identifying measures able to successfully reduce the impacts of disasters across different hazards. Please consider that this post does not aim to provide an exhaustive literature review on multi-hazard risk but only provides examples to support the presented concepts and definitions. Read episode 1: What is a -natural- hazard? Read episode 2: The concept of risk. Read episode 3: The disaster cycle. Read episode 4: Forecasting and modelling. References [1] https://www.undrr.org/terminology#R [2] Gill, J. C., & Malamud, B. D. (2014). Reviewing and visualizing the interactions of natural hazards. Reviews of Geophysics, 52(4), 680-722. https://doi.org/10.1002/2013RG000445 [3] Liu, B., Siu, Y. L., & Mitchell, G. (2016). Hazard interaction analysis for multi-hazard risk assessment: a systematic classification based on hazard-forming environment. Natural Hazards and Earth System Sciences, 16(2), 629-642. https://doi.org/10.5194/nhess-16-629-2016 [4] Tilloy, A., Malamud, B. D., Winter, H., & Joly-Laugel, A. (2019). A review of quantification methodologies for multi-hazard interrelationships. Earth-Science Reviews, 196, 102881. https://doi.org/10.1016/j.earscirev.2019.102881 [5] Mimura, N., Yasuhara, K., Kawagoe, S., Yokoki, H., & Kazama, S. (2011). Damage from the Great East Japan Earthquake and Tsunami-a quick report. Mitigation and adaptation strategies for global change, 16(7), 803-818. https://doi.org/10.1007/s11027-011-9297-7 [6] Kappes, M. S., Keiler, M., von Elverfeldt, K., & Glade, T. (2012). Challenges of analyzing multi-hazard risk: a review. Natural hazards, 64(2), 1925-1958. https://doi.org/10.1007/s11069-012-0294-2 [7] Gallina, V., Torresan, S., Critto, A., Sperotto, A., Glade, T., & Marcomini, A.

By Hedieh Soltanpour, posted on the blog of the Natural Hazards (NH) Division of the European Geosciences Union (EGU)Read the original article here Visualising Earth’s Dynamic Hazards. This illustration displays a range of natural hazards, from geological to meteorological, presented in a continuous landscape to emphasise the interconnected nature of these dynamic events. (Image created with OpenAI, DALL.E (2024)) Understanding multi-hazard approaches is crucial in an era of escalating natural hazards leading to disastrous impacts on Earth’s citizens. Triggered by the increasing frequency and severity of these events, this brief post provides a concise yet comprehensive overview of evolving paradigms in multi-hazard research and management. By exploring definitions, historical developments, and current trends, we highlight the critical importance of integrated strategies in mitigating impacts on society all in a nutshell. Foundation: Multi-hazard concept history at one glance It is important to acknowledge that the encouragement of multi-hazard approaches began with the work of Hewitt and Burton (1971) [1]; they emphasised the necessity of systematic cross-hazard approaches in understanding the hazard landscape of an area. However, the importance of multi-hazards was pronounced when this concept was first introduced in the United Nations’ Agenda 21 for Sustainable Development, held in Rio de Janeiro, Brazil, in 1992 under the title of “complete multi-hazard research” [2]. Subsequent international frameworks, including the Johannesburg Plan (UN, 2002), the Hyogo Framework for Action (2005) [3], and the more recent Sendai Framework for Disaster Risk Reduction (2015-2030) [4], have further underscored the importance of these strategies. The Sendai Framework, for instance, highlights the necessity for multi-hazard approaches, defining them as “the selection of multiple major hazards faced by a country, including the specific contexts in which hazardous events may occur simultaneously, cascadingly, or cumulatively over time, with consideration for their potential interrelated effects” [2]. Since then, the field has seen an exponential increase in research across various dimensions of multi-hazards, ranging from social to physical aspects [for example, 5-6]. This trend has persisted, reaching a point where the term “multi-hazard” has become a common buzzword in nearly every project related to natural hazards [7]. The unfolding story: Initial and ongoing confusion Initially, due to the unclear and varied definition of multi-hazards, studies mainly adopted approaches based on their own perceptions of this term, ranging from an “all-hazards-at-a-place approach” [1] to “more-than-one-hazard” approaches [8]. Kappes (2012) [8] provided an early definition of “multi-hazard” within the framework of risk reduction as “the totality of relevant hazards in a defined area”. This concept aimed to cover all potential environmental or man-made threats that could lead to harm, damage, or degradation. However, the criteria for defining the relevance of a hazard have been subject to debate, ranging from the introduction of a damage-based cut-off point for relevance by Hewitt and Burton (1971) [1], to the European Commission (2011) [9] proposing criteria based on the scale and impact of a hazard [8]. The traditional approach treats each hazard individually as a single event, often confusing decision-makers, particularly in critical circumstances. Managing natural hazards in isolation fails to recognise the interconnection and potential cascading effects that can arise from multiple hazards [8, 10-11]. Gill and Malamud (2016) [11] argue that narrowing the focus to a limited portion of the entire Earth system instead of understanding its dynamic interactions as a whole could lead to decisions that increase vulnerability to overlooked hazards. Consequently, the prevalence of single-hazard approaches inevitably leads to a distortion of management priorities. (Image created by OpenAI, DALL.E (2024)) Modelling perspective: Challenges in multi-hazard mapping Subsequently, multi-hazard mapping could not evidently remain safe from this ambiguity. Multi-hazard/ susceptibility maps are used to communicate complex scientific data with stakeholders. These maps serve as a communication tool to support and aid decision-makers by providing valuable information regarding disaster preparedness mitigation measures and informing urban planning and public policy [12]. To avoid single-hazard approaches, many analyses turned to superimposing separately modelled single hazards in a given area, which they are better called a multi-layer single-hazard approach [11], which is similar to the all-hazards-at-a-place approach, causing the same challenges in practice. In this regard, a full multi-hazard assessment/mapping has been encouraged, where the interrelationships of hazards (triggering, amplifying, compound and consecutive events) are also considered. The final thought: A question mark Moving beyond only assessing individual hazards is essential to manage natural hazards better. Equally important is gaining insights into the complex interplay between various hazards and their cascading relationships and effects. Since natural hazards do not occur in isolation but often exacerbate each other, leading to compounded effects, the strategies for understanding and mitigating them must also be collaborative, drawing from a wide range of scientific disciplines. When different hazards join forces to unleash significant damage, why should not scientists from various fields do the same? Just as these hazards compound their impact by working in tandem, our response should be equally collaborative, bringing together diverse expertise to tackle the challenge head-on. The fundamental step towards this collaboration is facilitating effective communication by establishing a common language where all different terms, yet conveying more or less the same concept, can be understood when discussing multi-hazards and their impacts on society. References [1] Hewitt K, Burton I (1971) Hazardousness of a place: a regional ecology of damaging events. Toronto Press, Toronto [2] UNEP (1992) Agenda 21. Tech. rep., United Nations Environment Programme [3] UNISDR, 2005. Hyogo Framework for Action 2005-2015: Building the Resilience of Nations and Communities to Disasters. United Nations, Hyogo, Japan [4] UNISDR. Sendai Framework for Disaster Risk Reduction 2015–2030. In UN Report UNISDR/GE/015; United Nations Office for Disaster Risk Reduction: Geneva, Switzerland [5] Joffe, H., Potts, H. W., Rossetto, T., Doğulu, C., Gul, E., & Perez-Fuentes, G. (2019). The Fix-it face-to-face intervention increases multihazard household preparedness cross-culturally. Nature human behaviour, 3(5), 453-461 [6] Tilloy, A., Malamud, B.D., Winter, H., Joly-Laugel, A., 2019. A review of quantification methodologies for multi-hazard interrelationships, 102881–102881 Earth-sci. Rev. 196 [7] Al-Khalili, J. host. (2023, June 6). Bruce Malamud on modelling risk for natural hazards. The life scientific

By Sophie Buijs and Marleen de Ruiter, posted on the blog of the Natural Hazards (NH) Division of the European Geosciences Union (EGU)Read the original article here In the past year, the world has witnessed many severe disasters caused by multiple hazards whose impacts overlapped in time and space. February this year, two severe earthquakes hit Syria and Turkey shortly after each other, followed by two more powerful earthquakes and over a hundred aftershocks in subsequent weeks [1,2]. The disaster caused over 48 thousand fatalities, and many people are still missing [3]. Another example is Afghanistan in June 2022, where an earthquake struck when people were already affected by a multi-year drought, followed by extreme rainfall and flooding in August [4,5]. Pakistan too was faced with an unfortunate series of events over the course of 2022. After a period of drought, heatwave-induced glacier melting combined with a heavy rain season resulted in devastating flooding, landslides, and disease outbreaks [4,6]. Additionally, the country was dealing with severe wildfires in May and June 2022 [7]. The United Nations Office for Disaster Risk Reduction defines such complex events as multi-hazard events involving the simultaneous or sequential occurrence of two or more hazards and their potentially interrelated effects [8]. For example, the flash floods in Pakistan were likely exacerbated by the wildfires in other regions [7]. Due to connections and feedback between multiple events, the combined impact of a multi-hazard event can be different from the sum of the impacts of multiple individual disasters [9]. Despite growing awareness among disaster risk researchers and managers of the importance of adopting a multi-hazard approach [10,11], complex multi-hazard events are often not recognised and reported upon as such by the mainstream media and disaster reporting websites. Such a fragmented approach to disaster reporting can result in an incomplete understanding of disasters and their impacts. It can limit the general public awareness of multi-hazard disasters, which in turn can affect disaster risk reduction and resilience-building efforts. For example, regarding the Afghanistan hazards, ReliefWeb – a humanitarian information service provided by the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) – reports the drought, earthquake, and flood as three separate disasters (Fig 1). The coincidence of these hazards is only briefly, and in some cases not at all, mentioned in the descriptions of the individual disasters [12-14].   Fig 1. A snapshot of the disasters as reported by ReliefWeb on their website for Afghanistan mid- and end-2022 [15].   In some instances, disasters are reported together (Fig 2), but this mainly occurs in the case of physically dependent disasters (i.e. where the occurrence of one hazard triggers that of another), while a multi-hazard event can also consist of multiple independent hazards with overlapping impacts [9].   Fig 2. A snapshot of the disasters as reported by ReliefWeb on their website for Afghanistan early 2012 [15].   This single-hazard-oriented reporting that can be observed in the provision of information by ReliefWeb and other humanitarian information services is also reflected in the way that disaster data is reported by aid organizations such as the International Federation of Red Cross and Red Crescent Societies (IFRC), but also more scientific sources, such as the Emergency Events Database EMDAT or the UNDRR’s Desinventar databases. The data that can be retrieved from these sources provide information per event, looking at one hazard at a time [16-18]. EMDAT provides a column for ‘associated disasters’, but this accounts, again, only for associations between physically dependent hazards. For example, the two tropical cyclones that hit northern Mozambique in 2019 only six weeks apart; these are not associated with each other in the EMDAT database, while the impacts of the second cyclone compounded with the residual impacts of the first [19]. The sequential disease outbreak resulting from the sanitation infrastructure disruptions [20] is also not linked to the storms as an associated disaster. While it is understandable that attributing impacts to individual natural hazards can be relevant for research purposes, it can be questioned if attributing impacts or emergency funding to single hazards is even possible when disaster impacts are strongly intertwined. Also, inconsistent and single-hazard-oriented reporting can often be observed when it comes to multi-hazard events in the mainstream media. When reporting on the first two severe earthquakes that struck Syria and Turkey in early February this year, the Guardian, for example, inconsistently uses ‘earthquake’ and ‘earthquakes’ in their articles: Two weeks after the Turkey-Syria Earthquakes – a photo essay Guardian article by Lorenzo Tondo and Ruth Michaelson, published February 21, 2023 Thousands dead, millions displaced: the earthquake fallout in Turkey and Syria Guardian article by Oliver Holmes, Elena Morresi and Finbarr Sheehy, published February 21, 2023     Another example is an article in the New York Times regarding the floods and looming food crisis faced by Pakistan in 2022:  ‘Very Dire’: Devastated by Floods, Pakistan Faces Looming Food Crisis New York Times article by Christina Goldbaum and Zia ur-Rehman, published September 11, 2022   While the article explains how the floods affected the country’s agricultural sector, for example, through the destruction of crops, this provides a simplified view of the actual situation. The food security conditions in the region, while worsened by the flood impacts, were already dire prior to the floods due to the drought and heat wave in early 2022, combined with economic instability and political unrest [21]. Research has shown that both consecutive hazard conditions and unstable socio-economic conditions can significantly affect the impacts of such a multi-hazard disaster [22]. However, recent news articles have taken initial steps towards a more comprehensive multi-hazard approach to disaster reporting. There are examples of articles discussing multiple hazards and their interconnections, like this article by the Guardian: Bushfires, ash rain, dust storms and flash floods: two weeks in apocalyptic Australia Guardian article by Kate Lyons, published January 24, 2020 This comprehensive article explains the natural hazards experienced by Australia in 2019-2020 (i.e. bushfires, extreme rain, flash floods, heatwave, mud streams, drought, dust and hail storms) and how they were interconnected. Recently the BBC even used the term ‘multi-hazard’ in their reporting [23]. This is

By Silvia De Angeli, posted on the blog of the Natural Hazards (NH) Division of the European Geosciences Union (EGU)Read the original article here COVID-19 has been a disruptive ‘tsunami’ that most countries were not prepared to handle. The pandemic has been representing a global slow-onset long-lasting disaster that has drastically challenged all emergency management systems worldwide. The pandemic slow-onset disaster has been characterized by a prolonged emergency phase with varying intensity levels, and a cyclic behavior, where the interpandemic, alert, pandemic, and transition phases [1] alternated for more than two years. In the first phases of the pandemic spread, the level of preparedness – including pre-existing protocols, development of testing and tracing capabilities, and the stockpile of personal protective equipment– was not adequate to deal with such an unexpected and complex event. Moreover, the health systems have been stretched to their limits, with a dramatic overload in intensive care units. Capano [2] identified that almost all Western countries had to go through a problem-recognition process before reacting effectively to the pandemic outbreak. After the first phase of denial (‘it is not happening’), then the countries went through the phases of normalization of the risk (‘it will not happen here’), underreaction (‘we must do something to show that we are doing something’), and finally arrived at the recognition and reframing (‘it is here, and it is our problem!’).   Is COVID-19 a black swan?  The scientific community and public opinion have widely debated whether the COVID-19 pandemic could be considered a Black Swan event, i.e., an event with an outsized impact, that is harder to predict and even harder to compute its probabilities. Professor John Drake, Director of the Center for the Ecology of Infectious Diseases at the University of Georgia (US), says it’s not [3]. Drake says that pandemics have always been part of human history and the number of recorded epidemics is vast. “Epidemics that affect a lot of people are less common, but certainly not rare” [3]. On the other hand, the COVID-19 pandemic has been different from any other disaster type and even other diseases [4]. Indeed, the COVID-19 pandemic management has involved temporal and spatial scales very different from those characterizing sudden-onset natural hazards such as earthquakes, floods, or landslides [5]. Regarding the temporal scale, the COVID-19 pandemic disaster has been ongoing for more than two years, with the number of cases and deaths continuously varying with time. As a consequence, there has not been a clear distinction between the impact and response phases and casualties can continue to increase even when response activities are already implemented [4]. Looking at the spatial scale, COVID-19 has almost simultaneously struck wide areas – even larger than a continent – contrary to all other disaster types that are geographically circumscribed. Several surrounding countries were coping at the same time with a high demand for emergency response resources, hampering the allocation of resources from one place to another, and leading to a reduction in international assistance [4,5].   A complex multi-risk scenario To make the scenario even more complex, the COVID-19 pandemic has overlapped and interacted with co-occurring disasters that happened all over the world since the beginning of the pandemic crisis [5,6,7,8], such as the earthquake in Croatia, the tropical cyclone Harold, and the floods in Western Europe. The lack of multi-hazard risk Early Warning Systems has increased the risk of compounding impacts originating from natural hazard events during the COVID-19 pandemic, including both the natural hazard disaster’s effects being worse than they would otherwise be without COVID-19 and an additional spread of COVID-19 due to the presence of a compound disaster [6]. A series of complex logistics and ‘‘asynergies” arose in this multi-hazard management since procedures and protocols for the integrated management of pandemics and natural hazards were underdeveloped or absent [9]. Indeed, emergency response for natural hazard disasters, such as an earthquake can necessitate evacuation and mass gathering measures, which are in contrast with the pandemic prevention strategies, such as physical distancing and home isolation. For example, staying at a shelter during the COVID-19 pandemic would potentially lead to a pandemic outbreak, highlighting what has been defined by Sayfouri et al. [10] as the “Contradictory Nature” of COVID-19 and the Earthquake Co-occurrence. The co-occurrence of COVID-19 and other natural hazards has dramatically highlighted the need for an improved scientific understanding of the interactions between natural hazards and pandemics, and for a better assessment of these complex multi-risk scenarios, where both synergies and trade-offs among disaster risk reduction measures can arise.   COVID-19 and natural hazards at EGU23  During the next EGU General Assembly, which will be held in Vienna from 23 to 28 April 2023, the Union Symposium US1 ”Managing compounding impacts from extreme events through societal crises”, will address how Europe can more effectively face multiple hazards and compounding impacts from extreme events through ongoing societal crises, such as the COVID-19 pandemic crisis. Moreover, complex multi-hazard risk scenarios and the interplay between natural hazards and pandemics will be explored in several scientific sessions inside the program of the Natural Hazards Division, such as NH9.2 New data and methods to explore the interplay between natural hazards and social vulnerability, NH9.3 Resilience to natural hazards: assessments, frameworks and tools, and NH10.1 Innovative approaches for multi-hazard risk assessments and their applications to disaster risk reduction and climate change adaptation, among others. References [1] World Health Organization (2017). Pandemic influenza risk management: a WHO guide to inform and harmonize national and international pandemic preparedness and response (technical documents). https://apps.who.int/iris/bitstream/handle/10665/259893/WHO-WHE-IHM-GIP-2017.1-eng.pdf?sequence=1&isAllowed=y [2] Capano, G. (2020). Policy design and state capacity in the COVID-19 emergency in Italy: if you are not prepared for the (un)expected, you can be only what you already are. Policy and Society, 39(3), 326-344. [3] Drake, J. “Was Covid-19 A Black Swan Event?” Forbes, Nov 11, 2021, https://www.forbes.com/sites/johndrake/2021/11/11/was-covid-19-a-black-swan-event/?sh=6b499411bd36. [4] Peleg, K., Bodas, M., Hertelendy, A. J., & Kirsch, T. D. (2021). The COVID-19 pandemic challenge to the All-Hazards Approach for disaster planning. International Journal of Disaster Risk Reduction, 55, 102103. [5] Terzi, S., De Angeli, S., Miozzo, D., Massucchielli, L. S., Szarzynski, J., Carturan, F., & Boni, G. (2022). Learning from the COVID-19 pandemic in Italy to advance multi-hazard disaster risk management. Progress in disaster science, 16, 100268.