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Item Gestão de desastres no Brasil: os planos de emergência e contingência em esferas estaduais e as Geociências(Universidade Federal de Santa Maria) Silva, Aline Freitas da; Mendes, Rodolfo Moreda; Dourado, FranciscoNos últimos anos, temos acompanhado no Brasil e no mundo grandes desastres que exigiram uma maior capacidade de resposta. Este fato já foi apontado até mesmo nas Conferências das Nações Unidas sobre Redução de Risco de Desastres. A contribuição e responsabilidade que o geocientista tem na identificação e avaliação de perigos e na classificação de áreas de risco - ações comuns à Gestão de Riscos - são relativamente mais conhecidas e discutidas, tanto no meio acadêmico quanto técnico, porém, o que não é ainda tão explorado é o papel, e consequentemente os protocolos institucionais e operacionais, do profissional de geociências nas etapas de preparação e resposta ao incidente, ou seja, na Gestão de Desastres. Este estudo tem como objetivo abordar alguns planos de emergência e contingência, em nível estadual, em uso no Brasil, analisando especialmente a inserção e contribuição das geociências para desastres associados a movimentos de massa. Certamente entende-se que a prevenção de desastres é a prioridade, mas saber como respondê-los de forma eficaz, rápida, segura e eficiente também é muito importante e para isso é necessário considerar se os documentos e protocolos existentes atendem adequada e suficientemente as demandas existentes.Item Obtaining 2D soil resistance profiles from the integration of electrical resistivity data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) resistance tests - applications in mass movements studies(Scientific Research Publishing) Bortolozo, Cassiano Antonio; Mendes, Tatiana Sussel Gonçalves; Motta, Mariana Ferreira Benessiuti; Simões, Silvio Jorge Coelho; Pryer, Tristan; Metodiev, Daniel; Andrade, Marcio Roberto Magalhães de; Moraes, Maiconn Vinicius de; Paula, Danielle Silva de; Bastos, Nélio José; Pampuch, Luana Albertani; Mendes, Rodolfo Moreda; Moraes, Marcio Augusto Ernesto deIn Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall; yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies.Item Os geocientistas na linha de frente dos desastres- uma análise do papel dos geólogos nas ações de preparação e resposta a desastres associados a movimentos de massa(Associação Brasileira de Geologia de Engenharia e Ambiental) Silva, Aline Freitas da; Mendes, Rodolfo Moreda; Dourado, FranciscoQuando um desastre ocorre imediatamente equipes de resposta são acionadas para lidar com as consequências geradas por ele e, de certa forma, contribuir no alívio do sofrimento humano. Essas equipes deveriam ser constituídas por inúmeros outros especialistas (além dos bombeiros, da defesa civil e das equipes médicas) com habilidades e conhecimentos específicos, trabalhando coordenada e multidisciplinarmente. Alguns trabalhos destacam como os geocientistas constituem uma primeira linha de defesa contra desastres geodinâmicos, contudo ainda persiste uma lacuna a respeito do papel e da importância do geólogo e as ações que ele pode desempenhar nas operações de desastre. Com isso em mente, esse estudo tem por objetivo analisar a contribuição dos geocientistas nas ações de Preparação e Resposta a um desastre, a partir de uma perspectiva ampla e de forma específica para os geólogos e os desastres associados aos movimentos de massa. Neste artigo são discutidos os resultados obtidos por meio de uma pesquisa de campo realizada a partir de um questionário online e direcionado a especialistas das áreas de gestão de riscos e de desastres, especialmente no Brasil. Constatou-se que a participação de geocientistas nas ações de preparação e resposta é fundamental, mas isso não se observa na prática. A criação de um mecanismo de atuação conjunta, incluindo profissionais de diferentes instituições, para prestarem apoio técnico-científico em emergências se faz altamente necessário bem como a elaboração de normas específicas que amparem a execução da profissão em desastres. Este trabalho fomenta a discussão quanto à necessidade e à importância dos geocientistas, em especial do geólogo, na linha de frente da resposta a um desastre geológico.Item Deadly disasters in southeastern South America: flash floods and landslides of February 2022 in Petrópolis, Rio de Janeiro(European Geosciences Union) Alcântara, Enner; Marengo, José Antonio; Mantovani, José; Londe, Luciana de Resende; San, Rachel Lau Yu; Park, Edward; Lin, Yunung Nina; Wang, Jingyu; Mendes, Tatiana Sussel Gonçalves; Cunha, Ana Paula; Pampuch, Luana; Seluchi, Marcelo; Simões, Silvio; Cuartas, Luz Adriana; Goncalves, Demerval; Massi, Klécia; Alvalá, Regina; Moraes, Osvaldo; Souza Filho, Carlos; Mendes, Rodolfo Moreda; Nobre, CarlosOn 15 February 2022, the city of Petrópolis in the highlands of the state of Rio de Janeiro, Brazil, received an unusually high volume of rain within 3 h (258 mm), generated by a strongly invigorated mesoscale convective system. It resulted in flash floods and subsequent landslides that caused the deadliest landslide disaster recorded in Petrópolis, with 231 fatalities. In this paper, we analyzed the root causes and the key triggering factors of this landslide disaster by assessing the spatial relationship of landslide occurrence with various environmental factors. Rainfall data were retrieved from 1977 to 2022 (a combination of ground weather stations and the Climate Hazards Group InfraRed Precipitation – CHIRPS). Remotely sensed data were used to map the landslide scars, soil moisture, terrain attributes, line-of-sight displacement (land surface deformation), and urban sprawling (1985–2020). The results showed that the average monthly rainfall for February 2022 was 200 mm, the heaviest recorded in Petrópolis since 1932. Heavy rainfall was also recorded mostly in regions where the landslide occurred, according to analyses of the rainfall spatial distribution. As for terrain, 23 % of slopes between 45–60∘ had landslide occurrences and east-facing slopes appeared to be the most conducive for landslides as they recorded landslide occurrences of about 9 % to 11 %. Regarding the soil moisture, higher variability was found in the lower altitude (842 m) where the residential area is concentrated. Based on our land deformation assessment, the area is geologically stable, and the landslide occurred only in the thin layer at the surface. Out of the 1700 buildings found in the region of interest, 1021 are on the slope between 20 to 45∘ and about 60 houses were directly affected by the landslides. As such, we conclude that the heavy rainfall was not the only cause responsible for the catastrophic event of 15 February 2022; a combination of unplanned urban growth on slopes between 45–60∘, removal of vegetation, and the absence of inspection were also expressive driving forces of this disaster.Item Curupira V1.0: Joint Inversion of VES and TEM for Environmental and Mass Movements Studies(Scientific Research an Academic Publisher) Bortolozo, Cassiano Antonio; Porsani, Jorge Luís; Pryer, Tristan; Benjumea, Jorge Luis Abril; Santos, Fernando Acácio Monteiro dos; Couto, Marco Antonio; Pampuch, Luana Albertani; Mendes, Tatiana Sussel Gonçalves; Metodiev, Daniel; Moraes, Marcio Augusto Ernesto de; Mendes, Rodolfo Moreda; Andrade, Marcio Roberto Magalhães deAn innovative inversion code, named “Curupira v1.0”, has been developed using Matlab to determine the vertical distribution of resistivity beneath the subsoil. The program integrates Vertical Electrical Sounding (VES), successful in shallow subsurface exploration and Time Domain Electromagnetic (TEM) techniques, better suited for deeper exploration, both of which are widely employed in geophysical exploration. These methodologies involve calculating subsurface resistivity through appropriate inversion processes. To address the ill-posed nature of inverse problems in geophysics, a joint inversion scheme combining VES and TEM data has been incorporated into Curupira v1.0. The software has been tested on both synthetic and real-world data, the latter of which was acquired from the Parana sedimentary basin which we summarise here. The results indicate that the joint inversion of VES and TEM techniques offers improved recovery of simulated models and demonstrates significant potential for hydrogeological studies.Item Development of a soil moisture forecasting method for a landslide early warning system (LEWS): Pilot cases in coastal regions of Brazil(Elsevier) Sousa, Isadora Araújo; Bortolozo, Cassiano Antonio; Mendes, Tatiana Sussel Gonçalves; Andrade, Marcio Roberto Magalhães de; Dolif Neto, Giovanni; Metodiev, Daniel; Pryer, Tristan; Howley, Noel; Simões, Silvio Jorge Coelho; Mendes, Rodolfo MoredaClimate change has increased the frequency of extreme weather events and, consequently, the number of occurrences of natural disasters. In Brazil, among these disasters, floods, flash floods, and landslides account for the highest number of deaths, the latter being the most lethal. Bearing in mind the importance of monitoring areas susceptible to disasters, the REMADEN/REDEGEO project of the National Center for Monitoring and Natural Disaster Alerts (Cemaden) has promoted the installation of a network of soil moisture sensors in regions with a long history of landslides. This network was used in the present paper as a base to develop a system for moisture forecasting in those critical zones. The time series of rainfall and moisture were used in an inversion algorithm to obtain the geotechnical parameters of the soil. Then the geotechnical model was used in a forward calculation with the rainfall prediction to obtain the soil moisture forecast. The landslide events of March 2020 and May 2022 in Guarujá and Recife, respectively, were used as study cases for the developed system. The obtained results indicate that the proposed methodology has the potential to be used as an important tool in the decision-making process for issuing landslide alerts.Item A precariedade dos serviços de esgotamento sanitário nos aglomerados subnormais do estado de São Paulo: uma chaga de difícil tratamento(Universidade Salvador) Vieira, José Moacir de Sousa; Valério Filho, Mário; Mendes, Rodolfo MoredaEste artigo tem como objetivo analisar a problemática da precariedade dos serviços de esgotamento sanitário em aglomerados subnormais no estado de São Paulo. A pesquisa apresenta dados atualizados sobre a coleta e tratamento de esgotos e um panorama da evolução do número de aglomerados subnormais no estado. A proliferação desses aglomerados se torna um problema ainda maior quando relacionada às dificuldades na universalização do saneamento básico nesses assentamentos, especialmente concernentes aos serviços de esgotamento sanitário. Este trabalho adota uma abordagem dialética e um procedimento metodológico baseado na técnica de documentação indireta, utilizando fontes estatísticas de órgãos governamentais e explorando bibliograficamente obras e pesquisas relacionadas ao tema. Os resultados deste estudo revelam os desafios enfrentados pelos moradores desses aglomerados no que diz respeito ao acesso aos serviços de esgotamento sanitário. Além disso, apontam que o aumento no número de aglomerados subnormais nos municípios paulistas é uma tendência preocupante, diretamente relacionada à falta de acesso à moradia digna e à precariedade do saneamento básico. Este estudo contribui para uma melhor compreensão das desigualdades sociais, lançando luz sobre as defasagens presentes nas condições de saneamento básico em comunidades periféricas. Além disso, oferece subsídios que podem orientar esforços destinados a melhorar essas condições e auxiliar os moradores dessas comunidades na superação das dificuldades inerentes à vida nos aglomerados subnormais. Esta pesquisa enfatiza a necessidade de políticas públicas e ações concretas para melhorar a qualidade de vida dessas populações vulneráveis e promover o acesso a serviços de saneamento independentemente de condição socioeconômica ou localização geográfica.Item Alert scenarios for the Metropolitan Region of Recife-PE based on monitoring of rainfall and soil humidity – a case study(Brazilian Association for Soil Mechanics and Geotechnical Engineering) Coutinho, Roberto Quental; Morais, Bruno Diego de; Mendes, Rodolfo Moreda; Andrade, Marcio Roberto Magalhães deIn Brazil, landslides are frequent, causing deaths and property damage, and occur under the influence of natural and/or anthropic conditions. Rain acts as the main non-anthropic agent in triggering this phenomenon. Because of this, the prediction of landslides becomes an essential tool for managing high-risk areas. The Metropolitan Region of Recife (MRR) has a large history with numerous cases of mass movements over the years. Currently, research points out improvements in the quality of forecasts by including hydrological information, such as soil moisture, in warning systems. Given the importance of measuring soil moisture in situ, a network of equipment consisting of rain gauges and capacitive moisture sensors was installed in the MRR, to monitor rainfall and soil moisture in an integrated manner. The objective of this article is to understand the hydrological conditions of the soil in two high-risk areas of the MRR, built over the Barreiras Formation to set the foundations for the development of a Landslide Early Warning System (LEWS) that integrates rain and humidity. The data showed that the variation in soil moisture is very dependent on rainfall and presents sudden variations in moisture with increasing hourly rainfall. The data also revealed that the monitored soils remained wet for approximately six months in the year 2022, highlighting the potential for moderate rainfall during this period to trigger landslides.Item Enhancing landslide predictability: Validating geophysical surveys for soil moisture detection in 2D and 3D scenarios(Elsevier) Bortolozo, Cassiano Antonio; Mendes, Tatiana Sussel Gonçalves; Egas, Harideva Marturano; Metodiev, Daniel; Moraes, Maiconn Vinicius de; Andrade, Marcio Roberto Magalhães de; Pryer, Tristan; Ashby, Ben; Motta, Mariana Ferreira Benessiuti; Simões, Silvio Jorge Coelho; Pampuch, Luana Albertani; Mendes, Rodolfo Moreda; Moraes, Marcio Augusto Ernesto deEvery year, Brazil grapples with the destructive impact of landslides, typically during the summer season. The National Centre for Monitoring and Alerts of Natural Disasters (Cemaden) places significant emphasis on studying these phenomena to understand their processes and causes more deeply. One key challenge faced in this endeavour is the procurement of geotechnical properties of the soil in high-risk areas, with soil moisture being a crucial factor. Collecting point samples for acquiring these geotechnical parameters is not only costly but also limited in providing a comprehensive two-dimensional or three-dimensional coverage. Therefore, the primary aim of the proposed project is to validate the method of acquiring soil moisture data through geophysical surveys in both 2D and 3D scenarios. Data was gathered from soil moisture stations within Cemaden's network and various collected samples to confirm the results. To generate more controlled yet realistic conditions, a sequence of field infiltration experiments was conducted. The findings, related to the ability of the geoelectric method to define soil moisture, derived from this project form an invaluable foundation for future investigations spearheaded by the Geodynamics Group and its collaborating institutions.Item ARHCS (Automatic Rainfall Half-Life Cluster System): A Landslides Early Warning System (LEWS) Using Cluster Analysis and Automatic Threshold Definition(Scientific Research Publishing) Bortolozo, Cassiano Antonio; Pampuch, Luana Albertani; Andrade, Marcio Roberto Magalhães de; Metodiev, Daniel; Carvalho, Adenilson Roberto; Mendes, Tatiana Sussel Gonçalves; Pryer, Tristan; Egas, Harideva Marturano; Mendes, Rodolfo Moreda; Sousa, Isadora Araújo; Power, JennyA significant portion of Landslide Early Warning Systems (LEWS) relies on the definition of operational thresholds and the monitoring of cumulative rainfall for alert issuance. These thresholds can be obtained in various ways, but most often they are based on previous landslide data. This approach introduces several limitations. For instance, there is a requirement for the location to have been previously monitored in some way to have this type of information recorded. Another significant limitation is the need for information regarding the location and timing of incidents. Despite the current ease of obtaining location information (GPS, drone images, etc.), the timing of the event remains challenging to ascertain for a considerable portion of landslide data. Concerning rainfall monitoring, there are multiple ways to consider it, for instance, examining accumulations over various intervals (1 h, 6 h, 24 h, 72 h), as well as in the calculation of effective rainfall, which represents the precipitation that actually infiltrates the soil. However, in the vast majority of cases, both the thresholds and the rain monitoring approach are defined manually and subjectively, relying on the operators’ experience. This makes the process labor-intensive and time-consuming, hindering the establishment of a truly standardized and rapidly scalable methodology on a large scale. In this work, we propose a Landslides Early Warning System (LEWS) based on the concept of rainfall half-life and the determination of thresholds using Cluster Analysis and data inversion. The system is designed to be applied in extensive monitoring networks, such as the one utilized by Cemaden, Brazil’s National Center for Monitoring and Early Warning of Natural Disasters.