Extreme Natural Events Research Articles

Changes in forest structure and composition in a pine-oak forest in Jaumave, Tamaulipas, Mexico

The pine-oak forest is distributed from the north to the south of Mexico, it has high susceptibility to degradation due to the increasein forest fires, pests, and other extremenatural events, which makes the need to conserve and sustainably use its resources relevant.Even when these forests are in a wide ecological niche (300 to 2500 m altitude), their populations are affected by the interaction ofextreme natural events and anthropogenic disturbances, causing changes in their structure and species composition. The floristiccomposition and forest structure of a pine-oak forest in Jaumave, Tamaulipas, were analyzed over 15 years, with three alternatesamplings in this period. A systematic samplingwas conducted in thirty-two circular plots of 1,000 m². In each plot, all trees with adiameter> 7.5 m were identified and measured. Basalarea (BA), density and species richnesswere calculated. In addition, the type offorest and disturbance type were identified. 3,567 individuals of sixteen distinct species (six familiesand six genera) were registered;the Quercus genus was the most abundant, representing 60% of the arboreal individuals. Three types of forests were defined: pine,oak, and pine-oak, based on the dominance of the basal area. Significant differences were found between measurement dates andfamilies(Pinaceae and Fagaceae, p <0.01). The BA increased with respect to the first and last measurement, increasing the BA of theoaks, while in pines it decreased. The differences were explained by the possible increase in pests, associated with prolongeddroughts registered between the years 2004 and 2010; causing a decrease in AB. Additionally, BA was affected by silviculturaltreatments applied in the control of debarker beetle (Dendroctonus sp.)

Drought assessment of China in 2002–2017 based on a comprehensive drought index

Drought, as an extreme natural disaster event, can cause or exacerbate water, food, and national security hazards. However, because of differences in the regional characteristics and applicability of drought indices, a more comprehensive drought index is necessary for drought assessment over large areas. Here, we propose a new detrended combined climatologic deviation index (Detrended-CCDI), and monitor drought over China from 2002 to 2017 on the basis of pixels on pixels by Detrended-CCDI. Results show that Detrended-CCDI has recorded monthly drought distribution results for China from April 2002 to June 2017, which are similar to those recorded by the Gravity Recovery and Climate Experiment - Drought Severity Index (GRACE-DSI), the Palmer Drought Severity Index (PDSI), the Standardized Precipitation-Evapotranspiration Index (SPEI), and the China Flood and Drought Disaster Bulletin. Detrended-CCDI has a good drought monitoring capability and captures drought recovery more quickly. Three main drought characteristics identified by Detrended-CCDI is similar to those demonstrated by other indices. The drought trend obtained by Detrended-CCDI is similar to that obtained by GRACE-DSI, but is more accurate and can detect more trends associated with becoming wetter or drier than PDSI and SPEI. The drought frequency obtained using Detrended-CCDI was lower than those identified by other indices, due to Detrended-CCDI combines all water layer and precipitation data. The regional drought events obtained by Detrended-CCDI and GRACE-DSI were almost identical (kappa average > 0.8), higher than those obtained by other indices. Our findings provide scientific guidance for drought monitoring and assessment over China.

Increasingly dry/wet abrupt alternation events in a warmer world: Observed evidence from China during 1980–2019

AbstractThe evolution of the frequency of dry/wet spells is a hot topic in global climate change research. The synergistic effects of dry/wet spells make their consequences far more significant than a single disaster, having considerable impacts on hydrology, ecology, and economies, especially in the context of global warming. In this study, the standardized precipitation evapotranspiration index (SPEI)‐based identification of dry/wet spells was used to explore the evolution of the frequency of dry/wet abrupt alternation (DWAA) events in the past four decades in China, makes up for the lack of research on the evolution of such compound disasters. China has been affected by dry/wet spells in many areas for a long time. Studies found that high‐frequency DWAA areas are concentrated in densely populated areas, China's essential food bases and core areas for economic development. Dry‐to‐wet (D–W) events and wet‐to‐dry (W–D) events basically increased or decreased at the same pace in this period. We innovatively find DWAA events (D–W events and W–D events) are projected to occur increasingly in a wider region of China. The frequency of D–W events across China has increased from 2.35 in the 1980s to 3.56 in the last decade, a 50% increase. On the other hand, W–D events increased from 2.6 to 3.23, increasing 24%. The three regions with the most remarkable changes in the past four decades are Inner Mongolia, northwest China, and north China, where D–W events increased by 121, 61, and 58%, respectively, and W–D events increased by 71, 57, and 61%, respectively. Hereby, it is vital to implement effective prevention against DWAA events in the area which has been neglected in the past decades because of lower frequency. These results may help policymakers develop suitable disaster mitigation plans for reducing the potential risks of extreme compound natural events.

Enhancing the Use of Flood Resilient Spatial Planning in Dutch Water Management. A Study of Barriers and Opportunities in Practice

Around the world, deltaic and coastal regions like the Netherlands are facing challenges from climate, change such as sea-level rise as well as more frequent and extreme natural events. Since 2009, the Dutch government has tried to mitigate flood vulnerability by deploying a balanced mix of flood protection measures, resilient spatial planning and crisis management (Multi-Layer Safety). However, recent evaluations have concluded that resilient spatial planning is (too) limitedly applied in practice. This article aims to understand the barriers and opportunities for resilient spatial planning in flood risk management by comparing two cases where resilient spatial planning was opted for: Dordrecht and the IJssel-Vecht Delta. The study suggests a large gap between the wide array of possible measures, and those that are actually realized in practice. Three physical-spatial barriers were identified: maximum flood depths, lack of space, and rigidity of the existing built environment. Additionally, institutional-organizational barriers were found, including: a false, low or non-existent safety perception or risk awareness, and therefore a lack of urgency to act; a lack of political and societal support; a suboptimal collaboration between stakeholders; ambiguity regarding responsibilities; finances and a cost-benefit imbalance; and a lack of human capital. Subsequently, the article explores possibilities to overcome these barriers. Overcoming these barriers can pave pathways for flood resilient spatial planning. The institutional-organizational barriers appear surmountable, whereas the physical-spatial barriers prove to be more problematic and form the most important restrictive factor for resilient spatial planning in flood risk management.

Old answers to new questions: using past disaster narratives to make today's organisations more resilient to the challenges of the Anthropocene

The Anthropocene will see a significant increase in the likelihood, frequency, and intensity of natural hazards. This altered context poses new challenges for global societies and economies. In addition to sustainability efforts, building resilience and reducing disaster risk thus become increasingly important strategic topics. This paper proposes that inspiration for how to respond to these challenges, and even use them for transformation and sustainable innovation, may lie in the distant past. By applying insights from sociological disaster studies and discourse analysis to earthquake narratives from ancient Greece, it will be shown how extreme natural events may, or may not, trigger disaster. Subsequently, implications for organisational resilience and disaster risk reduction in the Anthropocene will be derived.

Устойчивое развитие приморских регионов: географические и геополитические факторы и ограничения

Having formed at the end of the 20 th century, the concept of spatial development retains its relevance today. Yet, it is associated with a range of problems with its practical implementation and theoretical vindication, especially at a regional level. Attaining sustainable regional development, understood as a steady progress balanced across the economy, social industries and environmental protection, has been deemed impossible without identifying and considering regional development factors, such as geographical and economic-geographical position, environmental conditions and their geographical diversity, natural resource and their location, spatial features of the economy and the settlement structure. Coastal regions are affected by sundry other factors, such as the presence of a seacoast, viewed as a special resource, access to maritime transport and the availability of marine resources, including renewable ones, which are essential for sustainable development. The geopolitical situation of a region and the components of this situation are considered as geopolitical factors. Other limitations include extreme natural processes and events (large waves, tsunamis, typhoons etc.) The article aims to show that an integral geographical system or a combination thereof covering a region should be considered as the most appropriate object for assessment, planning and management of sustainable development, which is based on regional nature management including water and land resources. It is proposed that sustainable development criteria include economic, social and environmental metrics of regional development. Strategic marine and spatial planning and the monitoring of regional environmental management and development are identified as principal tools for attaining and maintaining sustainable development.

The Challenge of Social Vulnerability Assessment in the Context of Land Use Changes for Sustainable Urban Planning—Case Studies: Developing Cities in Romania

Urban growth triggers massive changes in land use cover, exacerbating extreme natural and technological events. In order for land use planning to be efficient, it requires the integration of comprehensive risk and vulnerability assessment. This paper aims to create a bridge between the existing vulnerability theories and their implementation in land use planning policies and proposes an innovative approach to determine whether the changes in the territorial dynamics of cities draw considerable changes in communities’ social vulnerability. The methodology identifies and selects three case studies from the Urban Atlas inventory, representative of the dynamics of large Romanian cities, taking into consideration the following hazards: earthquakes, floods, and technological hazards. Vulnerability was then assessed by assigning each land use class a specific vulnerability level. The methodology involved assessing the level of vulnerability specific to the situation in 2018 compared to 2006. The results showed that major changes in land use are related to the transition of areas with a low level of vulnerability to areas with a higher level of vulnerability as a result of the urban areas expansion to the detriment of natural and agricultural areas. This is generally translated into a higher degree of vulnerability due to an increased density of artificial elements and of population in the residential areas. The findings of the study of territorial dynamics in the proximity of large industrial operators did not reveal a tendency that differed from the general trend. Although many territorial changes have been observed in the period 2006–2018, it is necessary to extend the analysis, with the issue of the new versions of the Urban Atlas, to confirm the identified trends and to express the up-to-date situation.

Building a Natural Hazard Insurance System (NHIS): The Long-lasting Italian Case

The worrying growth of extreme natural events and their socioeconomic impact over time is increasingly fuelling the debate on how to manage disasters in view of developing resilient and sustainable societies. One possible financial tool may be represented by insurance against natural hazards, such as earthquakes, floods, and landslides. From this perspective, the current article considers legislative attempts to build a Natural Hazard Insurance System (NHIS) in Italy. The (never promulgated) bills proposed over a time span of about 30 years were analysed by: (a) A text-mining technique, considering the extraction of relevant data for the research; (b) the careful reading of the texts and their cross-correlated critical analysis. Approximately forty bills have been proposed since the 1980s and they mainly concern the proposal of an NHIS based on a certain degree of compulsoriness (the voluntary system is contemplated only on a subordinate basis). Two possible main hurdles to the promulgation of such laws were inferred: the insurance scheme to be adopted and the issue of illegal buildings. Furthermore, the item of natural hazard risk perception was a factor not adequately considered by the bills. Based on the critical scrutiny of the bills and taking advantage of international experiences, the establishment of a voluntary national scheme managed by a public authority with specific competences on NHIS is proposed.

Poverty and vulnerability transitions in Myanmar: An analysis using synthetic panels

AbstractWhile Myanmar achieved distinct progress in economic growth and poverty reduction over the past decade, extreme natural events; economic, political, and social crises; and the ongoing COVID‐19 shock pose serious challenges. This study complements previous analyses of poverty and vulnerability by providing a dynamic perspective for the period 2015–2017. Given the lack of longitudinal household data, the analysis relies on the synthetic panels approach to further our understanding of transitions between different states—poverty, vulnerability, non‐poverty—and the characteristics of the households associated with these transitions. Among the main results, we find that there was a relatively high probability for people, who were poor in 2015 to exit poverty in 2017, and that the probability of remaining in a vulnerable situation was non‐negligible. Moreover, the results point to important differences in the probability of transitioning between different states depending on household and location characteristics. While the COVID‐19 shock has likely increased the proportion of households in the vulnerable and poor groups, these results highlight the need to focus on households with specific characteristics that make them more at risk of remaining or falling into poverty than the rest of the population in a context of diminishing poverty rates and localized vulnerability pockets.

The United Nations Food Systems Summit (UNFSS) - What Next?

The United Nations Food Systems Summit (UNFSS) has come and gone. What did it achieve? I contributed to several pre-conference sessions. My message was always very clear, that we need to focus on people. We need to focus on the vulnerable. We need to focus on working towards world peace at all levels. As countries battle to contain the pandemic within their borders, we have failed to link this to mental health and conflicts. During a pandemic like one we have never seen before, few have made so much money by taking advantage of the working class and the hand-to-mouth strugglers in the society. As I went through the community recently after two years, I still witnessed a lot of suffering. What affected me most was not hunger and poverty due to loss of jobs, but parents being unable to afford school fees for their children. These are mostly children in boarding school. Yet, how can children stay in school without paying school fees, what will they eat at school? That is when people like me are called upon to step in. The UNFSS was predicated on the Sustainable Development Goals. GOAL ONE is the eradication of poverty. For a long time, we have talked about eradicating hunger. We do not seem to be succeeding as numbers of the hungry continue to soar, with extreme natural events displacing people, coupled with human conflicts, such as banditry, terror attacks, and survival escapades. Climate variability impacts are making it worse to sustain a viable food supply. One only has to watch global news to see floods, droughts, landslides, melting ice, and volcanic eruptions to realize that these are indeed strange times.

Diagnóstico da implantação das medidas estruturais e não estruturais para a prevenção e combate a inundação no munícipio de Joinville – Santa Catarina / Diagnosis of the implementation of structural and non-structural measures for the prevention and combat of flooding in the municipality of Joinville - Santa Catarina

The city of Joinville, in the northern region of the state of Santa Catarina, has a history of damages caused by floods, caused both by rainfall and by the impact of tides. This paper analyzes the most recent flood control measures in the three main hydrographic basins areas of Joinville, Hydrographic Basin of Cachoeira river (BHRC), Hydrographic Basin of Cubatão do Norte river (BHRCN) and Hydrographic Basin of Piraí River (BHRP). In the BHRC, in recent years there have been interventions in two sub-basins of the BHRC, contrution of macrodrainage has been made in the Morro Alto River and in the Mathias River it has been through recent works of alteration of its bed. In one of the sub-basins of the Piraí River, the Vermelho river basin, rainwater drainage galleries were built. Still in the Piraí Basin, there is a project to build micro drainage networks in the Vila Nova neighborhood (basin and paving of their respective roads as a goal of flood risk reduction). In the BHRCN one of the main works was the construction of an extravasation channel, dam and pourers for flow control. As non-structural measures, the hydro-meteorological monitoring of the Joinville Civil Defense (DCJ) and CEMADEN (National Center for Monitoring and Alerting Natural Disasters), the Evacuation Plan and Contingency Plan for Civil Protection and Defense for extreme natural events of the city developed by DCJ, the flood warning service of Joinville, included in the project of warning of the possible disasters of the Secretariat of Public Security of the State of Santa Catarina, implantation in Joinville of the Regional Center of Management of Risks and Disasters (CIGERD) and the zoning of areas subject to flooding or flooding available on the site of the Municipal Information System Georeferenced (SIMGeo). These actions are the result of the development of public policies that are demanded by a set of laws - municipal, state and federal - in force from time to time, and a historical series of laws and decrees related to flood control is found in the appendix of this work.

Do disasters provide an opportunity for regional development and change the societal trend of impacted communities?: Case study on the 1995 Kobe earthquake

Extreme natural events have a significant impact on communities. Post-disaster demographic changes can be an indicator of societal changes in communities. These changes in communities would differ reflecting the societal situation of the pre-event, even though the impact of damage and reconstruction projects is similar. However, it is still not clear what societal changes are specifically caused by disasters and thus are distinguishable from general changes. This study conducted a case study of the 1995 Kobe Earthquake and assessed the variations in impacts on regional demographics through comparisons with other regions with similar neighborhood characteristics. This study set out with three tasks: (1) to quantitatively classify neighborhood characteristics across Japan; (2) compare the demographics of the damaged area with those of others; and (3) assess the relationship between damage, demographics, and housing investments in affected areas. The results of the analysis show that an event concentrated neighborhood changes and facilitated them in heavily damaged areas, based on preexisting demands. This implies that the disaster in Kobe (1995), did not create new development demand and suggests that reconstruction after disasters should not be considered a development opportunity to accelerate regional growth but is actually dealing with preexisting demands.

Archaeoecology. The Application of Palaeoenvironmental Sciences for the Reconstruction of Human–Environment Interactions

The study of human–environment interactions is one of the mainstream topics in archaeological research, with increasing interest in the context of current societal challenges concerning environmental shifts related to climate change, sea-level rise, extreme natural events and also the exponential increase in anthropisation in recent decades [...]

Impact of Natural Extreme Events on Geophysical Fields in the Environment

Impact of Natural Extreme Events on Geophysical Fields in the Environment

Out-of-plane strengthening of adobe masonry using hemp fibre ropes: An experimental investigation

Adobe masonry structures are common in many parts of the world, particularly in developing countries. Whilst the ease of construction, low cost and familiarity of the material make it a popular building method, adobe is vulnerable to out-of-plane forces. Many countries where adobe structures are abundant are often subject to extreme natural events such as cyclones, seismic actions etc., these can result in significant horizontal forces leading to serious damage or collapse. This paper presents an experimental study of a novel strengthening method involving the application of hemp fibre rope nets to the surface of adobe walls. The method can be applied during construction and also as a retro-fit for existing structures. Hemp fibre ropes were chosen as the strengthening system in order to match the low cost, sustainability and buildability credentials of adobe itself. A series of plain and strengthened adobe panels were subject to bending, both parallel and perpendicular to the bed joints. The rope reinforced panels exhibited significant enhancements in strength and deformation capacity, with the latter achieving up to 10 times that of the un-strengthened case.

Review of HVDC systems for enhancing resilience after extreme natural events

Review of HVDC systems for enhancing resilience after extreme natural events

Recent advancements in multi-temporal methods applied to new generation SAR systems and applications in South America

Detection and continuous monitoring of Earth's ground surface changes, triggered by natural phenomena or induced by human activities, is nowadays possible using Earth Observation (EO) technologies. Indeed, the exploitation of remotely sensed data collected by constellations of new-generation satellite platforms, complemented with in-situ measurements and ground-based observation systems, represents a well-established practice to get valuable information on Earth's crust and subsurface dynamics. The effects of extreme natural or man-induced events (e.g., earthquakes, volcanic eruptions, flooding phenomena, sea-level rise, big fires, etc.) have severe societal and economic impacts. In particular, the technologies based on the use of Synthetic Aperture Radar (SAR) images reached significant improvements in the last decade due to the growing availability of vast amounts of data collected by multiple-satellite sensors operating at different frequency bands and with complementary viewing angles, polarization and acquisition modes. Accordingly, to process a large amount of SAR data in a timely fashion, up-to-date high-performance computing (HPC) methods and tools are required. This paper addresses the state-of-the-art of SAR technologies for the analysis of long sequences of multiple sets of SAR images and provides a perspective on the forthcoming improvements of these technologies. In particular, the emphasis is placed on novel interferometric SAR and change detection methods, giving an overview of how those processing techniques have been used for investigating sites located in South and Central America. Moreover, an overview of the new generation of SAR sensors' observational capability, especially in the field of ground deformation analysis for mitigating the risk associated with natural and human-induced hazards, is provided. COSMO-SkyMed, ALOS, Sentinel-1, and SAOCOM data are exploited to show how natural and human-induced terrain displacement phenomena can be detected and investigated in different portions (X-, L- and C-band) of the microwave spectrum using SAR technologies.

Analysis of risk and disaster reduction strategies in South American countries

There is a growing interest in disaster risk management due to an increasing vulnerability to extreme natural events and man-made disasters that prevent normal relations in societies worldwide. Thus, this study aimed to analyze disaster risk reduction (DRR) strategies in the context of seven Spanish-speaking South American countries, namely Argentina, Bolivia, Colombia, Chile, Ecuador, Paraguay, and Peru. We conducted an analysis of different DRR plans by using text mining techniques. Textual processing of the DRR strategies was conducted using computer-assisted qualitative data analysis. This process was complemented with the use of statistical models, such as the hierarchical cluster analysis and multiple correspondence analysis. Among the main results, 87 DRR strategies were found in the selected countries. The categorization of these strategies were different based on four management planning elements: planning based on social participation and stakeholder management, management planning based on disaster response, post-disaster continuity management planning, and management planning of essential sector continuity. Thus, this paper highlights the region's strengths and weaknesses and serves as a basis to follow up on the 2030 agenda for DRR discussed at Sendai in 2015.

A review of power system protection and asset management with machine learning techniques

Power system protection and asset management have drawn the attention of researchers for several decades; but they still suffer from unresolved and challenging technical issues. The situation has been recently exacerbated in the wake of the ever-changing landscape of power systems driven by the growing uncertainty and volatility subsequent to the vast renewable energy integration, more frequent natural extreme events due to climate changes, increasing malicious cyberattacks, and more constrained transmission systems as the result of load growth and limited investments. On the opposite side, the proliferation of advanced measuring devices such as phasor measurement units, emerging electric and non-electric sensors, and Internet of Thing (IoT)-enabled data gathering platforms continually expand/nourish the databases; they hence offer unprecedented opportunities to take the advantage of data-driven techniques. Machine learning (ML) as a principal class of artificial intelligence is the perfect match solution to this need and has newly revoked many researchers’ interests to tackle the problems excluding their exact/detailed models. This paper aims to provide an overview on applications of ML techniques in power system protection and asset management. This paper elaborates on issues pertaining to (1) synchronous generators, (2) power transformers, (3) transmission lines, and (4) special and system-integrity protection schemes. In addition to the opportunities offered by the ML techniques, this paper discourses on the barriers and challenges to the wide-spread application of ML techniques in real-world practices.

Coral reefs of India a review on their status and management

Coral reefs are one of the most ancient and dynamic ecosystems of India. Often referred to as the rainforests of the sea, coral reef ecosystems account for nearly one quarter of the total marine biodiversity, despite only covering 0.2% of the total seafloor by area. Coral reefs not only provide a sanctuary to a myriad of marine life but also play a key role in protecting the coastline from erosion. People living along the 8, 000 km long coastal stretch of India depend on coral reefs for their livelihood. India is centrally placed within the warm tropical region of the Indian Ocean and exhibits extensive coral reefs in its marine territories. Despite their immense importance, coral reefs are being damaged and destroyed due to natural and anthropogenic activities. The major reef formations in India are restricted to the Gulf of Mannar, Palk bay, Gulf of Kutch, Andaman and Nicobar Islands and the Lakshadweep islands. While the Lakshadweep reefs are atolls, the others are all fringing reefs. Patchy coral is present in the inter-tidal areas of the central west coast of the country. Coral reefs have been threatened by coral bleaching, ocean acidification, Extreme natural events, coral diseases, unmanaged coral fishing, and anthropogenic activities although laws are sufficient in theory to go for management and protection of the reefs in India. But still these fragile eco-systems are threatened and need to be conserved. It can be achieved by implementing the laws and adopting research oriented activities. The paper reviews the causes and management methods adopted to conserve these biodiversity rich regions.