18 research outputs found

    The contribution of historical information to flood risk management in the Tagus estuary

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    Estuarine areas are often affected by flood episodes with significant infrastructural and human damages caused by the overlap of different triggering factors. Currently flood risk management practices are subject to increased scrutiny by the public and relevant stakeholders requiring rigorous justification by flood risk managers and careful validation of the technical options and human and financial resources allocated to the management practice. Therefore, flood risk diagnosis through historical sources might constitute an important and effective first approach to public policies validation. In this paper is presented an estuarine flood damage database based on historical information and discussed as to the extent these types of sources can contribute to improve estuarine flood risk management in the Tagus estuary (Portugal). The paper discusses the methodological findings and limitations and highlights the usefulness of historical information integrating the results into the International Risk Governance Council (IRGC) risk management framework.info:eu-repo/semantics/publishedVersio

    Variações morfológicas induzidas por uma tempestade na Praia de Carcavelos, Portugal: contribuição para a gestão costeira

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    Field data based information on the coastal sediment dynamics becomes even more relevant for coastal managers in the present context of climate changes. Due to the sea level rise and the increase of frequency and intensity of coastal storms, coastal managers need to implement effective and efficient solutions for increasing coastal resilience, namely through reprofiling the beach for restoring the sediment balance and providing space for the beach natural dynamics. The study characterises and quantifies the morphological changes in an Atlantic urban sandy beach under extreme wave energy and sea level conditions. The erosion of the foreshore and backshore of this particular beach was characterised as function of the intensity and duration of the hydrodynamic forcing parameters (waves and sea level). This 24-hour duration storm event, which delivered to the beach a total energy of 1.7x109 J, caused the seaward displacement by the undertow current of approximately 3x103 m3 of median well sorted sand from the beach foreshore and backshore.Informação sobre a dinâmica sedimentar costeira baseada em dados de campo torna-se ainda mais relevante para gestores costeiros no presente contexto de alterações climáticas. Devido à subida do nível do mar e ao aumento da frequência e intensidade de tempestades marítimas, os gestores costeiros necessitam de implementar soluções eficazes e eficientes para melhorar a resiliência costeira, nomeadamente através do reperfilamento da praia para restabelecer o balanço sedimentar e conceder espaço para a dinâmica natural da praia. O estudo caracteriza e quantifica as variações morfológicas numa praia arenosa, urbana e Atlântica sob ação de condições extremas de energia das ondas e nível do mar. A erosão da face e do topo da praia foi caracterizada em função da intensidade e duração dos parâmetros forçadores hidrodinâmicos (ondas e nível do mar). Este evento de tempestade com duração de 24 horas, que transmitiu à praia uma energia total de 1.7x109 J, causou a extração de aproximadamente 3x103 m3 de areia média da face e do topo da praia e o seu transporte pela corrente de retorno para maiores profundidades.info:eu-repo/semantics/publishedVersio

    Improving Estuarine Flood Risk Knowledge through Documentary Data Using Multiple Correspondence Analysis

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    Estuarine margins are usually heavily occupied areas that are commonly affected by compound flooding triggers originating from different sources (e.g., coastal, fluvial, and pluvial). Therefore, estuarine flood management remains a challenge due to the need to combine the distinct dimensions of flood triggers and damages. Past flood data are critical for improve our understanding of flood risks in these areas, while providing the basis for a preliminary flood risk assessment, as required by European Floods Directive. This paper presents a spin-off database of estuarine flood events built upon previously existing databases and a framework for working with qualitative past flood information using multiple correspondence analysis. The methodology is presented, with steps ranging from a spin-off database building process to information extraction techniques, and the statistical method used was further explored through the study of information acquired from the categories and their relation to the dimensions. This work enabled the extraction of the most relevant estuarine flood risk indicators and demonstrates the transversal importance of triggers, since they are of utmost importance for the characterization of estuarine flood risks. The results showed a relation between sets of triggers and damages that are related to estuarine margin land use, demonstrating their ability to inform flood risk management options. This work provides a consistent and coherent approach to use qualitative information on past floods, as a useful contribution in the context of scarce data, where measured and documentary data are not simultaneously available.info:eu-repo/semantics/publishedVersio

    Dealing with Multisource Information for Estuarine Flood Risk Appraisal in Two Western European Coastal Areas

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    Estuaries are usually affected by compound flooding triggers that cause diverse territorial damages. While fluvial flood risk assessment frameworks are well established in the literature, integrated management instruments that deal with estuarine flood risk remain incomplete and often lacking. This research presents a methodology to extract relevant information from multiple sources post-event and a database building process that is applied to two contrasting estuaries (the Tagus River estuary in Portugal, and the Shannon River estuary in Ireland) in the Western European coastal area. Overall, a total of 274 documents were analyzed and the information was stored in two databases. Multiple correspondence analysis was applied to extract the most informative and relevant estuarine flood indicators. An integrated estuarine flood risk assessment framework is presented and discussed based on the extracted indicators. The framework is driven by two distinct dimensions (oceanic and hydrographic) and revealed the transversal position of triggers of estuarine floods, reflecting the compounding effects usually present in these areas. The results also highlight two levels of flood risk mostly based on damage typology.info:eu-repo/semantics/acceptedVersio

    Estuarine flooding in urban areas: enhancing vulnerability assessment

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    The assessment of vulnerability provides valuable knowledge in the risk assessment steps of a risk governance process. Given the multiscale, multilevel, and multisectorial aspects of flood risk, the diversified entities that directly and indirectly intervene in risk management require specific outputs from the assessment studies. Urban areas in estuarine margins are particularly exposed and vulnerable to flooding. Such interface conditions are found in the Old City Centre of the Seixal, located in the Tagus estuary, Portugal. Here, two distinct methodologies were applied for the assessment of territorial vulnerability. A regional, lower-scale, methodology explores the application of the statistical procedure based on the SoVI at the statistical block level. A second, local and higher-scale, methodology is based in data collected through field matrices at the building and statistical sub-block level. Comparison of results revealed that the lower-scale assessment provides information on the vulnerability drivers at the regional and municipal level. Nevertheless, only at a higher-scale, it is possible to characterize and differentiate the smaller geographical units of analysis that compose the Old City Centre of Seixal. The lower-scale vulnerability assessment allows a strategic response, based on adaptation measures such as spatial planning, institutional capacity building and public awareness. The local level assessment provides more accurate knowledge to support local emergency planning and the allocation of operational and material resources at the urban level. Nevertheless, rather than antagonistic, both models can be considered as complementary, having in mind the requirements of an holistic flood risk governance model.info:eu-repo/semantics/publishedVersio

    Enhancing estuarine flood risk management: comparative analysis of three estuarine systems

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    Estuarine flood risk management is a challenge for coastal managers since this type of system is usually complex due to the presence of multiple trigger combinations that can induce flood events affecting different types of human occupation. Furthermore, legal directives demanded countries to have flood risk assessment tools therefore enhancing knowledge on estuarine triggers and flood damage typologies is useful for coastal managers. In this study three different flood events are compared and contrasted, each one having occurred in a different estuarine system chosen based on a set of criteria (temporal proximity, occurrence of human damages and at least three flood triggers identified in each database). The diversity of data sources that characterizes each database was examined, for the three events, which are described in terms of triggers and damages. The comparison highlighted that the local context was important in the estuarine flood combination of triggers and disclosed two categories (one category comprising infrastructure economic and human damages; and another category involving circulation interruption and functions disruption) of flood damages common between the studied systems corresponding to different levels of relevance for management. The enhanced knowledge acquired allowed the construction of a conceptual framework for damages that can contribute to more adequate estuarine flood risk frameworks.info:eu-repo/semantics/publishedVersio

    The complexity of the coastal zone: definition of typologies in Portugal as a contribution to coastal disaster risk reduction and management

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    Mainland Portugal presents an extensive, diversified and complex coastal zone. This diversity gives rise to diverse geomorphologic features which support different densities of human occupancy and a range of land uses and activities. In this sense, the coastal zone becomes an area of great national strategic value, but has also into a multi-hazard zone. To understand this complexity, two statistical techniques, namely Cluster Analysis and Principal Component Analysis, were used to identify and differentiate, between the different coastal typologies, based on a set of variables that express the territorial complexity and the occurrences and impacts of coastal flooding. The chosen methodology enabled a diverse set of coastal typologies to be identified, which contributes towards differentiating local specific characteristics. The holistic and differentiating nature of the applied methodology and the results obtained allows it to contribute to the definition of mitigation strategies and the implementation of adaptation measures. The results enable us to define a set of typologies associated with Coastal Disaster Risk Reduction and Management which are an important contribution to comprehensive coastal flood risk assessment and management.info:eu-repo/semantics/publishedVersio

    mRNA-activated matrices encoding transcription factors as primers of cell differentiation in tissue engineering

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    Gene-activated matrices (GAMs) encoding pivotal transcription factors (TFs) represent a powerful tool to direct stem cell specification for tissue engineering applications. However, current TF-based GAMs activated with pDNA, are challenged by their low transfection efficiency and delayed transgene expression. Here, we report a GAM technology activated with mRNAs encoding TFs SOX9 (cartilage) and MYOD (muscle). We find that these mRNA-GAMs induce a higher and faster TF expression compared to pDNA-GAMs, especially in the case of RNase resistant mRNA sequences. This potent TF expression was translated into a high synthesis of cartilage- and muscle-specific markers, and ultimately, into successful tissue specification in vitro. Additionally, we show that the expression of tissue-specific markers can be further modulated by altering the properties of the mRNA-GAM environment. These results highlight the value of this GAM technology for priming cell lineage specification, a key centerpiece for future tissue engineering devices.This work has been funded by Ministerio de Economía y Competitividad (MINECO-RETOS, Grant MAT2017-84361-R, Feder Funds), Fundación BBVA 2014-PO0110 and Xunta de Galicia (Grupos de Referencia Competitiva, Feder Funds; Convenio para fomentar a actividade investigadora do persoal investigador finalista nas convocatorias de axudas do ERC no marco da H2020). AML was a recipient of a FPU grant from Ministerio de Economía y Competitividad (FPU12/05528)S
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