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Fresh coastal groundwater is a valuable water resource of global significance, but its quality is threatened by saltwater intrusion. Excessive groundwater abstraction, sea-level rise (SLR), land subsidence and other climate-related factors are expected to accelerate this process in the future. The objective of this study is to (a) quantify the impact of projected climate change and (b) explore the role of individual hydrogeological boundaries on groundwater salinization of low-lying coastal groundwater systems until 2100 CE. We employ numerical density-dependent groundwater flow and salt transport modeling for this purpose, using Northwestern Germany as a case. Separate model variants are constructed and forced with climate data, that is, projected SLR and groundwater recharge, as well as likely ranges of other hydrogeological boundaries, including land subsidence, abstraction rates and drain levels. We find that autonomous salinization in the marsh areas, resulting from non-equilibrium of the present-day groundwater salinity distribution with current boundary conditions, is responsible for >50% of the salinization increase until 2100 CE. Sea-level rise, land subsidence and drain levels are the other major factors controlling salinization. We further show that salinization of the water resources is a potential threat to coastal water users, including water suppliers and the agrarian sector, as well as coastal ecosystems. Regional-scale uplifting of drain levels is identified as an efficient measure to mitigate salinization of deep and shallow groundwater in the future. The presented modeling approach highlights the consequences of climate change and anthropogenic impacts for coastal salinization, supporting the timely development of mitigation strategies.

Submarine groundwater discharge (SGD) at the interface of land and sea is likely an important part of the global hydrological cycle and has started to attract the attention of a growing interdisciplinary scientific community. Independent of its composition, SGD is of particular relevance for estuarine and coastal areas, since it provides a direct pathway for element and water flow at the connection between land and ocean. Freshwater discharge rates and age may be highly variable, depending on the local hydrogeology. Since SGD may be enriched in nutrients, dissolved inorganic carbon, methane, and metals, it is linked to society-relevant issues, such as coastal eutrophication and the development of harmful algal blooms, the development of hypoxia, greenhouse effect, as well as ocean acidification to mention a few. Due to the direct measurement of the SGD composition and fluxes on small scales, however, biogeochemical and physical contributions to the adjacent coastal water column can be deduced.

Groundwater abstraction and drainage are considered to be the main drivers for the salinization of low-lying coastal groundwater systems, while the role of past boundary conditions is less clear. In this study, 3-D paleo-hydrogeological variable-density groundwater flow and salt transport modeling (“paleo-modeling”) is applied to reconstruct the evolution of groundwater salinities during the Holocene, that is, the last 9,000 years, in Northwestern Germany. Novel aspects of this study include the consideration of highly resolved time-variant boundary conditions in a 3-D paleo-modeling framework, for example, sea-level rise, surface elevation and coastline changes, development of drainage networks and groundwater abstraction, as well as the quantification of isolated processes impacting salinization. Results show that salinization was a function of sea-level rise from 9000 BP until 1300 CE. The creation of the dike line ∼1300 CE set the starting point for increasing anthropogenic control of the hydro(geo)logical system: changes in surface elevation and drainage of low-lying marshes have become main drivers for salinization after 1600 CE when peat was artificially degenerated. Moreover, changes in the dike line caused by storm floods impacted the salinities. Model results for 2020 CE match well with present-day salinity observations. Yet, salinization will continue in the future, as the hydro(geo)logical system has not reached an equilibrium. The presented paleo-modeling framework can be viewed as a blueprint for similar low-lying coastal groundwater systems, influenced by marine transgression and human development. Thereby, it enables the reconstruction of meaningful present-day salinity distributions, serving as a vital basis for modeling future groundwater systems in a changing climate.

For millennia, humans have gravitated towards coastlines for their resource potential and as geopolitical centres for global trade. A basic requirement ensuring water security for coastal communities relies on a delicate balance between the supply and demand of potable water. The interaction between freshwater and saltwater in coastal settings is, therefore, complicated by both natural and human-driven environmental changes at the land-sea interface. In particular, ongoing sea level rise, warming and deoxygenation might exacerbate such perturbations. In this context, an improved understanding of the nature and variability of groundwater fluxes across the land-sea continuum is timely, yet remains out of reach. The flow of terrestrial groundwater across the coastal transition zone as well as the extent of freshened groundwater below the present-day seafloor are receiving increased attention in marine and coastal sciences because they likely represent a significant, yet highly uncertain component of (bio)geochemical budgets, and because of the emerging interest in the potential use of offshore freshened groundwater as a resource. At the same time, “reverse” groundwater flux from offshore to onshore is of prevalent socio-economic interest as terrestrial groundwater resources are continuously pressured by overpumping and seawater intrusion in many coastal regions worldwide. An accurate assessment of the land-ocean connectivity through groundwater and its potential responses to future anthropogenic activities and climate change will require a multidisciplinary approach combining the expertise of geophysicists, hydrogeologists, (bio)geochemists and modellers. Such joint activities will lay the scientific basis for better understanding the role of groundwater in societal-relevant issues such as climate change, pollution and the environmental status of the coastal oceans within the framework of the United Nations Sustainable Development Goals. Here, we present our perspectiv

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Subterranean estuaries are connective zones between inland aquifers and the open sea where terrestrial freshwater and circulating seawater mix and undergo major biogeochemical changes. They are biogeochemical reactors that modify groundwater chemistry prior to discharge into the sea. We propose that subterranean estuaries of high-energy beaches are particularly dynamic environments, where the effect of the dynamic boundary conditions propagates tens of meters into the subsurface, leading to strong spatio-temporal variability of geochemical conditions. We hypothesize that they form a unique habitat with an adapted microbial community unlike other typically more stable subsurface environments. So far, however, studies concerning subterranean estuaries of high-energy beaches have been rare and therefore their functioning, and their importance for coastal ecosystems, as well as for carbon, nutrient and trace element cycling, is little understood. We are addressing this knowledge gap within the interdisciplinary research project DynaDeep by studying the combined effect of surface (hydro- and morphodynamics) on subsurface processes (groundwater flow and transport, biogeochemical reactions, microbiology). A unique subterranean estuary observatory was established on the northern beach of the island of Spiekeroog facing the North Sea, serving as an exemplary high-energy research site and model system. It consists of fixed and permanent infrastructure such as a pole with measuring devices, multi-level groundwater wells and an electrode chain. This forms the base for autonomous measurements, regular repeated sampling, interdisciplinary field campaigns and experimental work, all of which are integrated via mathematical modelling to understand and quantify the functioning of the biogeochemical reactor. First results show that the DynaDeep observatory is collecting the intended spatially and temporally resolved morphological, sedimentological and biogeochemical data. Samples and

The simulation of thermal, hydraulic, and mechanical coupled processes can be a decisive factor in the integrity assessment of geotechnical and geological barriers. Modelling decisions, such as the representation of heterogeneity and the constitutive models used, significantly impact the simulation outcome (Wagener and Pianosi, 2019). Furthermore, numerical inputs to the simulation, i.e. material parameters and boundary conditions, are subject to uncertainty. This results in a lower confidence level of the outcome, even if the overall simulation framework is well validated.To derive robust conclusions from such analyses, it is important to quantify the relative impact of modelling decisions and inputs on certain quantities of interest. Parameter uncertainties can be quantified by their forward propagation through the discretized problem (Helton, 1994), providing a natural frame of reference for quantifying structural uncertainty (Bond et al., 2007), such as the representation of heterogeneity, and for model validation. This contribution will focus on the latter aspects.We present research on workflows for the unification of evaluating uncertainty in experimental data and certain modelling decisions. We first focus on parameter uncertainty quantification and the resulting conclusions concerning the chosen modelling approach. Hereafter, scale questions are addressed in the context of heterogeneity and anisotropy, based on selected case studies. We close by discussing two example applications, namely one at the Underground Research Laboratory (URL) scale (Mount Terri Full-Scale Emplacement (FE) experiment) and one at the repository scale (ANSICHT Ton Nord model).This work is done as part of the Bundesministerium für Umwelt, Naturschutz, nukleare Sicherheit und Verbraucherschutz (BGE URS) research cluster.

The selective modification of unprotected carbohydrates for cross-linking in waterborne coatings. As you all know we use a lot of plastic and polymers. There are big problems with plastic since they are oil based and produce a lot of waste. That way they contribute to the problem of global heating because of their carbon footprint. Also in coatings such polymers are used to protect our metal and wooden surfaces. Even though they do not end up the same way as waste, the oil based polymers do not help the carbon footprint. New inventions are tried and used but often they are expensive and difficult to make. What if there already was a cheap and green alternative to the “old oil-based plastics and polymers”? Indeed, it is already possible to take plant-based feedstocks for the production of polymers. Moreover, it is even possible to take organic waste feedstocks, e.g. from industry in form of crap shells. Most of these organic feedstocks have in common, that they are built from large chains of sugar molecules, the so-called polysaccharides. These polysaccharides are perfect starting materials for the production of plastic alternatives because they are already polymerized into large chains and already consist of a large number of functionalities. Functionalities are necessary to perform further chemistry to modify the chains’ properties. The whole process of modifying the bio-waste feedstock is not only an opportunity but also a challenge. The goal is to do all chemistry in aqueous solutions so that no toxic solvents are needed. The same applies to the reagents used for the modifications. It is for example necessary to use catalysts that do not contain heavy metals. This is where the ARC CBBC started its flagship project of waterborne coatings. Coatings are in general also just a protective layer made of plastic. My part of this project is to modify polysaccharides so that they consist of a handle afterwards, which can be used to cross-link c

For millennia, humans have gravitated towards coastlines for their resource potential and as geopolitical centres for global trade. A basic requirement ensuring water security for coastal communities relies on a delicate balance between the supply and demand of potable water. The interaction between freshwater and saltwater in coastal settings is, therefore, complicated by both natural and human-driven environmental changes at the land–sea interface. In particular, ongoing sea-level rise, warming and deoxygenation might exacerbate such perturbations. In this context, an improved understanding of the nature and variability of groundwater fluxes across the land–sea continuum is timely yet remains out of reach. The flow of terrestrial groundwater across the coastal transition zone and the extent of freshened groundwater below the present-day seafloor are receiving increased attention in marine and coastal sciences because they likely represent a significant yet highly uncertain component of (bio)geochemical budgets and because of the emerging interest in the potential use of offshore freshened groundwater as a resource. At the same time, “reverse” groundwater flux from offshore to onshore is of prevalent socio-economic interest, as terrestrial groundwater resources are continuously pressured by over-pumping and seawater intrusion in many coastal regions worldwide. An accurate assessment of the land–ocean connectivity through groundwater and its potential responses to future anthropogenic activities and climate change will require a multidisciplinary approach combining the expertise of geophysicists, hydrogeologists, (bio)geochemists and modellers. Such joint activities will lay the scientific basis for better understanding the role of groundwater in societally relevant issues such as climate change, pollution and the environmental status of the coastal oceans within the framework of the United Nations Sustainable Development Goals. Here, we present our perspectives on

In this paper, the governing equations of non-isothermal two-phase flow in unsaturated, deformable porous media are presented based on different representations of the gaseous phase along with their implementations in the open-source FEM code OpenGeoSys 6. As one implementation utilises the Richards equation to represent the unsaturated system whereas the second implementation relies on a two-component two-phase flow formulation, the impact of a free gaseous phase on model predictions is illustrated by a series of tests of increasing complexity, motivated by similar investigations in Task C of the DECOVALEX 2023 project. We demonstrate that the governing equations of both implementations collapse and become identical in fully saturated regions and that the numerical implementations remain stable in the special cases. Furthermore, the implicit assumptions made in the Richards equation are explicitly applied to the physically more complex and comprehensive TH2M model. Thus, the impact of a constant residual gas pressure on the model predictions is investigated. Finally, the examples chosen for this work feature thermal consolidation and pore fluid pressurisation effects in the Opalinus Clay due to heat release from a nuclear waste canister as well as dry-out with subsequent resaturation of a bentonite buffer around the heat source. All test cases are evaluated on the level of the governing equations of each model as well as on the level of results obtained by each model for a discussion of conceptual model uncertainty.

In this paper, thermo-hydro-mechanically (THM) coupled processes triggered during the construction, operation and closure of a deep geological repository for heat generating, high level radioactive waste are discussed based on a generic disposal concept. For this purpose, we are using the numerical non-isothermal two-phase-two-component flow in deformable porous media ((THM)-M-2) implementation (Grunwald et al. in Geomech Geophys Geo-energy Geo-resour, 2022) in the open-source software OpenGeoSys (Bilke et al. in Transport Porous Media 130(1):337-361, 2019, ). THM coupled effects covered in this work focus on single and two-phase-flow phenomena, gas and heat generation as well as poro-elastic medium deformation. A suitable set of benchmarks covering aforementioned THM-effects, devised in the scope of the BenVaSim benchmarking project (Lux et al. in Synthesis report. BenVaSim-International Benchmarking for Verification and Validation of TH2M Simulators with Special Consideration of Fluid Dynamical Processes in Radioactive Waste Repository Systems. Tech. rep., 2021, ) is chosen and one additional benchmark is presented, allowing for the demonstration and comparison of the OGS-6 (THM)-M-2 implementation against results obtained by other well-established codes used in the field. Apart from the code comparison, the benchmarks also serve as means to analyze THM coupled processes in a repository based on very simplified geometries. Therefore, they can help to improve the process understanding, but any quantitative results should not be interpreted as predictions of the behaviour of a real repository. The results obtained in this work agree well with the results presented by the project partners in BenVaSim-both in single phasic, fully liquid saturated cases and in partially saturated two phase regions. Hence, the suitability of the OGS-6 (THM)-M-2 implementation for the application in the field of radioactive waste management, supporting the safety case and analyzing the i

In this chapter, we investigate hydro-mechanical effects in the Opalinus Clay, especially those leading to cracking. We present a methodology comprising laboratory and field scale experiments, as well as the development and application of numerical approaches.

GeomInt2 is the follow-up project to the joint project “Geomechanical Integrity of Host and Barrier Rocks—Experiment, Modelling and Analysis of Discontinuities (GeomInt)”. The results of GeomInt made essential contributions to the analysis of the origin and development of discontinuities in clay, salt and crystalline rocks. Discontinuities are considered in many forms, be it as volumetrically distributed damage macroscopically representing fissures in the rock microstructure, discontinuities that can form anew at phase interfaces as well as discrete cracks or fracture networks. The pathways created or extended by these discontinuities entail the risk of migration of fluid phases from deep to near-surface geological layers and must therefore be taken into account in geotechnical safety analyses.

Understanding the interaction of terrestrial freshwater and seawater in the subterranean estuary (STE) is an important factor when considering nutrient fluxes from land to sea. State-of-the-art research describes the STE by a tide-induced upper saline recirculation cell, a freshwater discharge tube and a deep saltwater wedge. However, recent numerical modelling and shallow hydrogeochemical investigations for high-energy beaches indicate that multiple saline recirculation cells may exist and affect the land-sea interaction. Electrical Resistivity Tomography (ERT) and Direct Push (DP) technologies are common tools to explore the subsurface. Due to their sensitivity to the electrical conductivity of pore water, they permit investigating the STE. This study combines ERT and DP to image the salinity distribution within the STE of a meso-tidal, high-energy beach. We actively incorporate the DP data into the ERT inversion and use geostatistical regularization for closing the resolution gap. For the first time, our experimental results confirm the existence of several 10-20 m deep reaching upper saline recirculation cells and corresponding brackish discharge locations generated by a pronounced runnel-ridge beach system in 2019, whereas in 2021 only a single cell was displayed for a flat topography at the time.

Underground Research Laboratories (URLs) allow geoscientific in-situ experiments at large scale. At the Mont Terri URL in Switzerland, international research groups conduct numerous experiments in parallel. The measured and simulated data as well as research results obtained from them are highly relevant as they improve the general understanding of geological processes, for example in the context of radioactive waste disposal. Unfortunately, the data obtained at the test site is often only available to researchers who are directly involved in a particular experiment. Furthermore, typical visualisation techniques of such data by domain scientists often lack spatial context and accessing and exploring the data requires prior technical knowledge and a high level of effort.We created a digital replica of the Mont Terri URL and thereby implemented a prototype of a Virtual Experiment Information System that integrates highly heterogeneous data from several different sources. It allows accessing and exploring the relevant data embedded in its spatial context without much prior technical knowledge. Both, simulation results and observation data are displayed within the same system. The 4D visualisation approach focuses on three exemplary experiments conducted at Mont Terri and is easily transferable to other experiments or even other URLs. The Unity Game Engine has been used to develop the prototype. This allowed to build the application for various output devices like desktop computers or Virtual Reality hardware without much additional effort. The implemented system reduces the technical effort required to access and explore highly relevant research data and lowers the cognitive effort usually needed to gain insights from measurements, simulation models and context data. Moreover, it promotes exchange among research groups by enabling interactive visualisations embedded in the URL’s spatial context. In addition, a future use of the system for the communication of scientifi

In the published article, there was an error concerning the FE Experiment. Incorrect information was used regarding the heaters’ power and temperature. A correction has been made to Chapter 3: Visualisation of Selected Experiments, Sub-section 3.3 “Full- Scale Emplacement Experiment”, Paragraph 1. The sentence previously stated: “They work with up to 1,500W each and emit heat up to 195°C.” The corrected sentence now states: “They work with up to 1,350W each and emit heat up to 135°C.” The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.

For millennia humans have gravitated towards coastlines for their resource potential and as geopolitical centres for global trade. A basic requirement ensuring water security for coastal communities relies on a delicate balance between the supply and demand of potable water. The interaction between freshwater and saltwater in coastal settings is, therefore, complicated by both natural and human-driven environmental changes at the land-sea interface. In particular, ongoing sea level rise, warming and deoxygenation might exacerbate such perturbations. In this context, an improved understanding of the nature and variability of groundwater fluxes across the land-sea continuum is timely, yet remains out of reach. The flow of terrestrial groundwater across the coastal transition zone as well as the extent of freshened groundwater below the present-day seafloor are receiving increased attention in marine and coastal sciences because they likely represent a significant, yet highly uncertain component of (bio)geochemical budgets, and because of the emerging interest in the potential use of offshore freshened groundwater as a resource. At the same time, “reverse” groundwater flux from offshore to onshore is of prevalent socio-economic interest as terrestrial groundwater resources are continuously pressured by overpumping and seawater intrusion in many coastal regions worldwide. An accurate assessment of the land-ocean connectivity through groundwater and its potential responses to future anthropogenic activities and climate change will require a multidisciplinary approach combining the expertise of geophysicists, hydrogeologists, (bio)geochemists and modellers. Such joint activities will lay the scientific basis for better understanding the role of groundwater in societal-relevant issues such as climate change, pollution and the environmental status of the coastal oceans within the framework of the United Nations Sustainable Development Goals. Here, we present our perspective

This article studies the meaning and rhetorical function of conversion stories in four Colonial texts: the epic poem La Araucana by Alonso de Ercilla and three chronicles about the Arauco War and the evangelization in the Kingdom of Chile. On the one hand, there are narratives of “mortal conversion” in which the converted native dies immediately afterwards. One the other hand, the chronicle Restauración de la Imperial y conversión de almas infieles by Juan de Barrenechea y Albis contains an account of “productive conversion”, in which the native reproduces the structure of the Christian family after conversion. These conversion stories aim to both the necessity and the limitations of the evangelizing project of the conquest, the distance between baptism and the “complete” Christianization of the native, and the various ways in which evangelization is hampered by the violence of war, exploitation of the native and sexual violence, Este artículo se pregunta por el sentido y función retórica de los relatos de conversión que encontramos en cuatro textos coloniales: el poema épico La Araucana de Alonso de Ercilla y tres crónicas que hablan sobre la guerra de Arauco y la evangelización en el Reino de Chile. Se reconocen, por un lado, relatos de “conversión mortal”, en los que el indígena que se convierte muere inmediatamente después, y un relato de “conversión productiva”, en el que el indígena reproduce la estructura de la familia cristiana tras la conversión. Esta última está representada en la crónica Restauración de la Imperial y conversión de almas infieles del mercedario Juan de Barrenechea y Albis. Estos relatos de conversión aluden tanto a la necesidad como a las limitaciones del proyecto evangelizador de la conquista, a la distancia que hay entre el bautismo y la cristianización “completa” del indígena y a las diversas formas en las que la evangelización se ve entorpecida por la violencia propia de la guerra, la explotación del indígena y la violencia sexual.

Coastal observatories are key to improve the understanding of processes within the coastal area and their interactions with regional and global environmental changes. The land-sea transition zone is an essential area that allows research on unique scientific questions under anthropogenic and natural influences. Amid the Wadden Sea UNESCO world natural heritage site – the largest tidal flat region worldwide – the barrier island Spiekeroog is an excellent location for an observatory studying land-sea interactions. The integrated Spiekeroog Coastal Observatory (SCO) operated by the Institute for Chemistry and Biology of the Marine Environment (ICBM, University of Oldenburg) is dedicated to interdisciplinary marine and terrestrial ecosystem research. Its position within the tidal area and the multitude of research-field addressed establishes the SCO as a unique coastal observatory with the potential to identify patterns in long-term variability and simultaneously understanding short-term changes. The establishment of the Time-Series Station (TSS) Spiekeroog in a tidal channel west of Spiekeroog back in 2002 laid the foundation of the SCO. Since then, the observatory is expanding continuously and is now representing a valuable asset supporting education, industry, government, and environmental conservation efforts in the area. Summing up the infrastructure and technical components, the importance of the SCO is evident, and individual projects greatly benefit from the collaboration with the partners in and the elements of the SCO. Harmonizing the infrastructure and competences of contributing partners will be a next step to further consolidate the SCO. A challenge poses the maintenance of the SCO based on projects, which is focused on the addition of new facilities, not maintaining, refurbishing, or (if necessary) deconstructing existing infrastructure. Therefore, structural support and funding opportunities not linked to projects but aiming to sustain observational capac

High-variety earth science data is being produced at an increasing velocity and accuracy to power environmental research, reinforced by the advancements in Internet of Things (IoT) technologies and the widespread deployment of internet-connected sensors. Utilizing this enormous data set for context-aware and on-site analysis that is enhanced with realistic visualizations and event dynamics transcends the capabilities and reach of traditional information systems for environmental management. So much data from diverse sources requires integrated and interactive solutions to allow the professionals, academics, decision makers, and public to perceive the complete picture regarding the consequences of climate change as well as the environmental issues revolving around a community, and to discover actionable knowledge upon context-informed analysis.Mixed reality and serious gaming present an immense potential in earth sciences to overcome the challenges of engaging stakeholders and community members in decision-making and disaster preparedness, communicating huge environmental data within geospatial context, and simulating nonreplicable extreme events for evaluation. Furthermore, the incorporation of gamification and interaction into data exploration and decision-making for risk reduction and environmental management shows significant potential for participatory planning, collaborative learning, and building conceptual understanding of physical phenomena and processes.Here, we encourage original research articles on the development and evaluation of virtual and augmented reality experiences as well as serious gaming approaches with application in the earth science and water resources domain. Topics of interest include, but are not limited to:- Disaster preparedness, mitigation, and recovery;- First-responder training and emergency response;- Hydrological data exploration and visualization;- In-situ geospatial visualizations and community scenario simulations;- Visual anal

We propose a formulation for non-isothermal two-component two-phase flow through deformable porous media. The approach covers phase transitions among both phases, i.e. liquid phase components evaporate into the gas phase while gas phase components dissolve or condensate into the liquid phase. These phase transitions always take place in thermodynamic equilibrium. The set of model equations is thereby largely independent of the specific constitutive relations. Starting from general equilibrium equations, we show the evolution of the system of weak formulations of all governing equations, which are then discretised with Taylor-Hood elements in a standard finite element approach. The model equations and the construction of the constitutive equilibria are implemented in the open-source simulator OpenGeoSys, which can be freely used and modified. To verify the implementation, we have selected a number of complementary test cases covering a wide range of process couplings. The numerical model is compared with analytical and semi-analytical solutions of these problems as well as with experimental results. It is shown in the paper that by including thermodynamic effects, solid mechanics, and phase transition processes, the proposed numerical model covers many characteristic features of unsaturated geomaterials and can be employed for the description of a broad range of problems encountered in geotechnical engineering.

To enable safe geological storage of high-level radioactive waste, a comprehensive understanding of the overall system must include relevant physical processes, geological and geotechnical boundary conditions. In the Mont Terri Rock Laboratory (Switzerland) the Cyclic Deformation (CD-A) experiment has been established with the excavation of the two twin niches in the year 2019. To study the impact of the different climatic conditions on the hydraulic and mechanical processes in the claystone, an extensive investigation program has been carried out. As part of the CD-A experiment, we present here a multidisciplinary interpretation including geological characterisation, geodetic and geotechnical measurements, numerical modelling and visualisation techniques. The period under consideration runs between September 2019 and March 2021. Geological mappings illustrate different zones of tectonically induced faulted rock in the sandy facies of the Opalinus Clay and laserscans conducted at regular intervals show small convergence of the niches. While the deformation around the open niche tends to continue, extensometer measurements around the closed twin indicate a reduced deformation after the first months. First coupled hydraulic-mechanical simulations demonstrate that the numerical approach is capable of reproducing the hydro-mechanical behaviour qualitatively, including the extent of the desaturated zone. The application of state-of-the-art visualisation techniques allows simultaneous evaluation and comparison of geological features, measurements and simulation results. This holistic approach - discussed here exemplary for the mechanical effects - provides a valuable basis for the rating of the impact of geologic structures, material heterogeneities, and climatic conditions on the Opalinus Clay. Thus, it can be a valuable component for the safe construction and operation of a repository and for the long term safety assessment.

The 4th Industrial Revolution is the culmination of the digital age. Nowadays, technologies such as robotics, nanotechnology, genetics, and artificial intelligence promise to transform our world and the way we live. Artificial Intelligence Ethics and Safety is an emerging research field that has been gaining popularity in recent years. Several private, public and non-governmental organizations have published guidelines proposing ethical principles for regulating the use and development of autonomous intelligent systems. Meta-analyses of the AI Ethics research field point to convergence on certain principles that supposedly govern the AI industry. However, little is known about the effectiveness of this form of Ethics. In this paper, we would like to conduct a critical analysis of the current state of AI Ethics and suggest that this form of governance based on principled ethical guidelines is not sufficient to norm the AI industry and its developers. We believe that drastic changes are necessary, both in the training processes of professionals in the fields related to the development of software and intelligent systems and in the increased regulation of these professionals and their industry. To this end, we suggest that law should benefit from recent contributions from bioethics, to make the contributions of AI ethics to governance explicit in legal terms.

The utilization of artificial intelligence (AI) applications has experienced tremendous growth in recent years, bringing forth numerous benefits and conveniences. However, this expansion has also provoked ethical concerns, such as privacy breaches, algorithmic discrimination, security and reliability issues, transparency, and other unintended consequences. To determine whether a global consensus exists regarding the ethical principles that should govern AI applications and to contribute to the formation of future regulations, this paper conducts a meta-analysis of 200 governance policies and ethical guidelines for AI usage published by public bodies, academic institutions, private companies, and civil society organizations worldwide. We identified at least 17 resonating principles prevalent in the policies and guidelines of our dataset, released as an open-source database and tool. We present the limitations of performing a global scale analysis study paired with a critical analysis of our findings, presenting areas of consensus that should be incorporated into future regulatory efforts. All components tied to this work can be found in https://nkluge-correa.github.io/worldwide_AI-ethics

This open access book summarizes the results of the collaborative project “GeomInt: Geomechanical integrity of host and barrier rocks - experiment, modeling and analysis of discontinuities” within the Program: Geo Research for Sustainability (GEO: N) of the Federal Ministry of Education and Research (BMBF). The use of geosystems as a source of resources, a storage space, for installing underground municipal or traffic infrastructure has become much more intensive and diverse in recent years. Increasing utilization of the geological environment requires careful analyses of the rock–fluid systems as well as assessments of the feasibility, efficiency and environmental impacts of the technologies under consideration. The establishment of safe, economic and ecological operation of underground geosystems requires a comprehensive understanding of the physical, (geo)chemical and microbiological processes on all relevant time and length scales. This understanding can only be deepened on the basis of intensive laboratory and in-situ experiments in conjunction with reliable studies on the modeling and simulation (numerical experiments) of the corresponding multi-physical/chemical processes. The present work provides a unique handbook for experimentalists, modelers, analysts and even decision makers concerning the characterization of various types of host rocks (salt, clay, crystalline formations) for various geotechnical applications.

Subterranean estuaries (STEs), the subsurface mixing zones of terrestrial groundwater and seawater, substantially influence solute fluxes to the oceans. Solutes brought by groundwater from land and solutes brought from the sea can undergo biogeochemical reactions, often mediated by microbes, which determine the composition of fluids discharging from STEs (e.g., submarine groundwater discharge), which may have consequences showing in coastal ecosystems. While at the local scale (meters), processes have been intensively studied, the impact of STE processes on solute fluxes to the coastal ocean remains poorly constrained at the regional scale (kilometers). In the present communication, we review the processes that occur in STEs, focusing mainly on fluid flow and biogeochemical transformations of nitrogen, phosphorus, carbon, sulfur and trace metal. We highlight the spatio-temporal dynamics and measurable manifestations of those processes. The objective of this contribution is to provide a perspective on how tracer studies, geophysical methods, remote sensing and hydrogeological modeling could exploit such manifestations to estimate the regional-scale impact of processes in STEs on solute fluxes to the coastal ocean.

An essential scientific goal of the GeomInt project is the analysis of potentials and limitations of different numerical approaches for the modelling of discontinuities in the rocks under consideration in order to improve the understanding of methods and their synergies with regard to theoretical and numerical fundamentals. As numerical methods, the “Lattice Element Method” (LEM), the non-continuous discontinuum methods “Discrete Element Method” (DEM), the “Smoothed Particle Hydrodynamics” (SPH), the “Forces on Fracture Surfaces” (FFS) as well as the continuum approaches “Phase-Field Method” (PFM), “Lower-Interface-Method” (LIE), “Non-Local Deformation” (NLD) and the “Hybrid-Dimensional Finite-Element-Method” (HDF) will be systematically investigated and appropriately extended based on experimental results (Fig. 3.1).

This open access book summarizes the results of the collaborative project “GeomInt: Geomechanical integrity of host and barrier rocks - experiment, modeling and analysis of discontinuities” within the Program: Geo Research for Sustainability (GEO: N) of the Federal Ministry of Education and Research (BMBF). The use of geosystems as a source of resources, a storage space, for installing underground municipal or traffic infrastructure has become much more intensive and diverse in recent years. Increasing utilization of the geological environment requires careful analyses of the rock–fluid systems as well as assessments of the feasibility, efficiency and environmental impacts of the technologies under consideration. The establishment of safe, economic and ecological operation of underground geosystems requires a comprehensive understanding of the physical, (geo)chemical and microbiological processes on all relevant time and length scales. This understanding can only be deepened on the basis of intensive laboratory and in-situ experiments in conjunction with reliable studies on the modeling and simulation (numerical experiments) of the corresponding multi-physical/chemical processes. The present work provides a unique handbook for experimentalists, modelers, analysts and even decision makers concerning the characterization of various types of host rocks (salt, clay, crystalline formations) for various geotechnical applications.

A potential repository site for high-level radioactive waste should ensure the highest possible safety level over a period of one million years. In addition to design issues, demonstrating the integrity of the barrier is essential as it ensures the long-term containment of radioactive waste. Therefore, a multi-disciplinary approach is necessary for the characterization of the surrounding rock and for the understanding of the occurring physical processes. For site selection, however, the understanding of the respective system is essential as well: Do fault zones exist in the relevant area? Are these active and relevant for interpreting system behavior? What is the role of the existing heterogeneities of the claystone and how do these site-dependent conditions influence the physical effects? To answer these questions, the site-selection procedure requires underground exploration, which includes geophysical and geological investigations on milli- to decameter scales. Their results serve as the basis for numerical modelling. This combined, multi-disciplinary interpretation requires extensive knowledge of the various methods, their capabilities, limitations, and areas of application.In the cyclic deformation (CD-A) experiment in the Mont Terri rock laboratory, the hydraulic–mechanical effects due to excavation and the climatic conditions within the rock laboratory are investigated in two niches in the Opalinus Clay. The twin niches differ mainly with regard to the relative humidity inside them, but are also characterized by different boundary conditions such as existing fault zones, the technical construction of the neighboring gallery, etc. In order to gain insights into the relevance of the individual influences, comparative studies are being carried out on both niches. The presented results provide a first insight into the initial experimental years of the CD-A long-term experiment and illustrate the benefits of multi-disciplinary investigations in terms of system und

The FFS method (see Sect.  3.2.1) was developed to simulate direct shear tests. To provide a tool for the project work and get things easier done a graphical user interface (GUI) was also created. The GUI simply calls all necessary functions by letting the user either fill form fields or choose input files from the working folder. The rock parameters and the conditions of the direct shear test with the normal stress levels and shear displacements have to be selected. If an experiment is simulated the lab results can be selected as a text file so a visual comparison is possible. The geometry has to be loaded as a point cloud or an artificial surface can be generated. With small modifications the code can do multiple executions using artificial surfaces.

Data management includes the development and use of architectures, guidelines, practices and procedures for accurate managing of data during the entire data lifecycle of an institutional unit or a research project. Data are defined as different information units such as numbers, alphabetic characters, and symbols that are particularly formatted and can be processed by computer. The data in the project is provided by various actors which can be GeomInt partners, their legal representatives, employees, and external partners.

The basic idea of Model-Experiment-Exercises (MEX) is to link modelling and experimental works from the very beginning i.e. in the conceptual phase. Due to the complexity of each part in the systems analysis, this combination is sometimes lost. Moreover, both models and experiments require highly sophisticated tools and equipment as well as highly specialized professionals, which also necessitate adequate measures and incentives for collaboration. GeomInt is introducing the MEX concept exactly for this purpose. Therefore, the following MEX studies occupy the largest part of the GeomInt book and feed most of the publications with research material.

The present paper gives an overview of the GeomInt project “Geomechanical integrity of host and barrier rocks—experiment, modelling and analysis of discontinuities” which has been conducted from 2017–2020 within the framework of the “Geo:N Geosciences for Sustainability” program. The research concept of the collaborative project is briefly introduced followed by a summary of the most important outcomes. The research concept puts geological discontinuities into the centre of investigations—as these belong to the most interesting and critical elements for any subsurface utilisation. Thus, while research questions are specific, they bear relevance to a wide range of applications. The specific research is thus integrated into a generic concept in order to make the results more generally applicable and transferable. The generic part includes a variety of conceptual approaches and their numerical realisations for describing the evolution of discontinuities in the most important types of barrier rocks. An explicit validation concept for the generic framework was developed and realised by specific “model-experiment-exercises” (MEX) which combined experiments and models in a systematic way from the very beginning. 16 MEX have been developed which cover a wide range of fundamental fracturing mechanisms, i.e. swelling/shrinkage, fluid percolation, and stress redistribution processes. The progress in model development is also demonstrated by field-scale applications, e.g. in the analysis and design of experiments in underground research laboratories in Opalinus Clay (URL Mont Terri, Switzerland) and salt rock (research mine Springen, Germany).

As a result of the GeomInt research project (Chap. 1) a broad combined experimental and numerical platform for the investigation of discontinuities due to swelling and shrinking processes (WP1, Sect. 2.3), pressure-driven percolation (WP2, Sect. 2.4) and stress redistribution (WP3, Sect. 2.4) for important reservoir and barrier rocks (clay, salt, crystalline) has been developed. Model comparisons for damage and fracture processes driven by different processes provide information on the optimal areas of application of the numerical methods (Sect. 2.5).

The use of the subsurface as a source of resources, a storage space and for installing underground municipal or traffic infrastructure has become much more intensive and diverse in recent years. In addition to classical anthropogenic interventions such as mining, oil and gas production or tunnel construction, other forms of underground use have come into the focus of economic, political and scientific research, particularly in connection with the transformation of energy systems.

We present results from an international model comparison study involving a series of controlled fault activation experiments in Opalinus Clay at the Mont Terri Laboratory, Switzerland. The fault activation experiments were conducted in situ by water injection at variable pressure from boreholes targeting different parts of the Main Fault crossing several tunnels and galleries of the Mont Terri Laboratory. The model simulations focused on (1) an experiment activating a discontinuity (fracture or minor fault) within the damage zone of the main fault, and (2) an experiment activating discontinuities close to the core of the Main Fault. The experimental data consist of coupled hydraulic and mechanical responses monitored at an injection borehole and a monitoring borehole located a few meters away. After overcoming several modeling issues along with necessary model developments, a reasonably good agreement was achieved between the modeling results and the field observations. The fault activation experiments displayed an abrupt flow rate increase associated with a sudden fracture opening and rupture propagation after the injection pressure reached above the estimated normal stress on the fracture. This was followed by an abrupt flow rate decrease, indicating hydraulic closing, once the injection pressure decreases to an estimated 1–2 MPa below the stress normal to the opened fracture. The models were able to capture this abrupt hydromechanical behavior, including an observed dominant opening behavior along with the rupture propagation, while the spatial extent of the shear rupture and the quantity of peak injection flow were the most challenging to predict.

This article presents new thoughts on the limits of the epic form in Pedro de Oña’s Arauco domado (1596), drawing attention on two devices that undermine the panegyric of the viceroy García Hurtado de Mendoza: the debatable nature of the viceroy›s exploits and the growing relevance of indigenous figures as the story progresses. The representation of the latter emulates, in turn, the pattern of the pastoral novel, an issue that has been read by critics as a purely imitative attitude of the author, but which is presented here as an instrument to manifest a Creole nostalgia for the homeland, Este artículo presenta nuevas consideraciones sobre las limitaciones del carácter épico del Arauco domado (1596) de Pedro de Oña, poniendo especial énfasis en dos dispositivos que menoscaban el encomio al virrey García Hurtado de Mendoza: el carácter debatible de las hazañas del virrey y la creciente relevancia de las figuras indígenas a medida que avanza la narración. Estas últimas siguen, a su vez, el patrón de la novela pastoril, cuestión que ha sido leída por la crítica como una actitud puramente imitativa del autor, pero que aquí se presenta como un instrumento para manifestar una nostalgia criolla por el suelo patrio

Seit Inkrafttreten des Stromeinspeisegesetzes im Jahr 1991 und des Erneuerbaren-Energien-Gesetzes (EEG) im Jahr 2000 entwickeln sich die erneuerbaren Energien (EE) insbesondere im Strombereich rasant. Wurden im Jahr 1990 nur ca. 19 TWh Strom aus EE erzeugt, waren es im Jahr 2017 schon ca. 216 TWh. EE nehmen nach Braun- und Steinkohle damit den zweiten Rang im deutschen Strommix ein. Ihr Anteil am Bruttostromverbrauch lag im Jahr 2017 bereits bei ca. 36 %. Ein weiterer kräftiger Ausbau ist notwendig, um bis zum Jahr 2050 den Zielwert von 80 % Anteil am Bruttostromverbrauch zu erreichen.Die Notwendigkeit des Umbaus des Energiesystems sowie die positiven Effekte der EE für die Reduktion von Treibhausgasemissionen sind unstrittig. Klimaschutz ist eine wichtige Voraussetzung für den Erhalt von Natur und Landschaft und trägt dazu bei, das Überleben von Arten langfristig zu sichern. Galten EE lange Zeit als per se umweltfreundlich, so treten mit zunehmendem Ausbau Auswirkungen auf Natur und Umwelt deutlicher zu Tage, die zu zunehmenden Konflikten mit den Zielen des Naturschutzes führen können. Eine bundesweite, systematische und wiederkehrende Beschreibung, die die durch die Errichtung und den Betrieb von Anlagen zur Erzeugung und Übertragung von Strom aus EE verursachten Beeinträchtigungen von Natur und Umwelt bündelt, gibt es derzeit noch nicht. Ein solches Monitoringsystem könnte unter anderem sowohl die nationale Berichterstattung zum Ausbau der EE um die Auswirkungen auf Natur und Landschaft erweitern als auch mittelfristig das Wirkungswissen schrittweise verbessern. Problematische Entwicklungen könnten damit frühzeitig erkannt und vermieden werden. Ziel des Forschungsvorhabens „Naturschutzfachliches Monitoring des Ausbaus der erneuerbaren Energien im Strombereich und Entwicklung von Instrumenten zur Verminderung der Beeinträchtigung von Natur und Landschaft“ war daher eine möglichst systematische Erfassung und Darstellung (Monitoring) der Entwicklungen und daraus fol

Scientific visualization deals with increasingly complex data consisting of multiple fields. Typical disciplines generating multivariate data are fluid dynamics, structural mechanics, geology, bioengineering, and climate research. Quite often, scientists are interested in the relation between some of these variables. A popular visualization technique for a single scalar field is the extraction and rendering of isosurfaces. With this technique, the domain can be split into two parts, i.e. a volume with higher values and one with lower values than the selected isovalue. Fiber surfaces generalize this concept to two or three scalar variables up to now. This article extends the notion further to potentially any finite number of scalar fields. We generalize the fiber surface extraction algorithm of Raith et al. [RBN∗19] from 3 to d dimensions and demonstrate the technique using two examples from geology and climate research. The first application concerns a generic model of a nuclear waste repository and the second one an atmospheric simulation over central Europe. Both require complex simulations which involve multiple physical processes. In both cases, the new extended fiber surfaces helps us finding regions of interest like the nuclear waste repository or the power supply of a storm due to their characteristic properties.

This article features a simple method for describing the phase equilibrium of the ternary water-salt-carbon dioxide system. At first, an iterative solution is shown using well known equations of state and solubility correlations to predict the compositions of liquid and gas phases in a saline aquifer. By virtue of several assumptions, iterations can be avoided entirely in order to use the method for demanding large-scale numerical simulations. Subsequently, the iterative method as well as the simplification are evaluated against experimental data. Both solutions provide adequate accuracy for engineering problems such as subsurface carbon dioxide storage.

Subterranean estuaries (STEs) are land-ocean interfaces where meteoric fresh groundwater mixes with intruding seawater in a coastal aquifer, before discharging into the adjacent water column. In contrast to surface estuaries, STEs have the potential to amplify concentrations of constituents such as copper (Cu) and iron (Fe) due to long residence times and reductive dissolution of mineral phases along the groundwater flowpaths. However, oxidative precipitation of Fe and Mn at the sediment-water interface may scavenge many constituents again before they reach the coastal water column. Hence, the geochemical impact of the suboxic to anoxic submarine groundwater discharge (SGD) on the oxygenated coastal ocean relies on the capability of constituents such as Cu and Fe to stay in solution across redox boundaries. Here, we propose that dissolved organic matter (DOM) in the STE plays a pivotal role in the speciation of Cu and Fe through (i) fueling reductive dissolution and (ii) providing ligands to form stable metal-DOM complexes, increasing their transfer from the STE into the coastal ocean. We investigated the concentrations and speciation of Cu and Fe, and DOM chemical characteristics, in two beach STEs of a barrier island. By combining well-established techniques with novel quantification and speciation approaches from both the inorganic and organic geochemical realm (size-fractionation filtration, ferrozine detection, voltammetry, sequential DOM extraction, and ultra-high resolution mass spectrometry) we characterized metal-DOM associations down to the molecular level. Overall, pore water from both STEs was enriched with Cu and Fe compared to seawater, which indicated transfer potential for both trace metals across the sediment-water interface. However, Fe gradients from pore water to surface were steeper than those for Cu, indicating a larger net transfer of the latter compared to the former. Our voltammetry data showed that Cu was exclusively organically bound in bo

Submarine groundwater discharge (SGD) is a ubiquitous source of meteoric fresh groundwater and recirculating seawater to the coastal ocean. Due to the hidden distribution of SGD, as well as the hydraulic- and stratigraphy-driven spatial and temporal heterogeneities, one of the biggest challenges to date is the correct assessment of SGD-driven constituent fluxes. Here, we present results from a 3-dimensional seasonal sampling campaign of a shallow subterranean estuary in a high-energy, meso-tidal beach, Spiekeroog Island, Northern Germany. We determined beach topography and analyzed physico-chemical and biogeochemical parameters such as salinity, temperature, dissolved oxygen, Fe(II) and dissolved organic matter fluorescence (FDOM). Overall, the highest gradients in pore water chemistry were found in the cross-shore direction. In particular, a strong physico-chemical differentiation between the tidal high water and low water line was found and reflected relatively stable in- and exfiltrating conditions in these areas. Contrastingly, in between, the pore water compositions in the existing foreshore ridge and runnel system were very heterogeneous on a spatial and temporal scale. The reasons for this observation may be the strong morphological changes that occur throughout the entire year, which affect the exact locations and heights of the ridge and runnel structures and associated flow paths. Further, seasonal changes in temperature and inland hydraulic head, and the associated effect on microbial mediated redox reactions likely overprint these patterns. In the long-shore direction the pore water chemistry varied less than the along the cross-shore direction. Variation in long-shore direction was probably occurring due to topography changes of the ridge-runnel structure and a physical heterogeneity of the sediment, which produced non-uniform groundwater flow conditions. We conclude that on meso-tidal high energy beaches, the rapidly changing beach morphology produces

Die Autorin stellt die Frage, ob das subjektive Alter in Abgrenzung zum chronologischen Alter ein Untersuchungsmerkmal in der Weiterbildungsforschung sein kann. In der Dissertation entwickelt sie ausgehend von der Alters- und Weiterbildungsforschung neue Untersuchungsperspektiven. Basis sind zwei Studien, die mittels Regressionsanalysen und Strukturgleichungsmodellen ausgewertet werden. In ihren Ergebnissen beschreibt die Autorin das Erkenntnispotenzial des subjektiven Alters als Untersuchungsvariable und skizziert mögliche Forschungsfelder, die unter diesem Aspekt bearbeitet werden könnten.

Claystone is a potential host rock for the longterm storage of highly radioactive waste. This type of rock is characterised by a complex, highly-coupled hydraulic-mechanical behavior. The physical understanding of the related effects is of great importance to understand the stability and the integrity of a potential repository. The CD-A experiment addresses these effects in the Mont Terri underground rock labora-tory (Switzerland). A comparison of the processes in two parallel niches will be car-ried out: one niche is characterized by effects due to seasonal desaturation whereas desaturation effects are minimized for the other by maintaining a constant high hu-midity. A comprehensive measuring program as well as numerical simulations (OGS, CodeBright) are planned to investigate the impact of the humidity on the seasonal and longterm deformation behavior.Ein komplexes, stark gekoppeltes hydraulisch-mechanisches Verhalten ist charakte-ristisch für Tonstein. Zur Beurteilung von Standsicherheitsfragen ebenso wie für die Langzeitsicherheit eines potentiellen Endlagers für hochradioaktive, Wärme entwi-ckelnde Abfälle ist das physikalische Verständnis dieser Effekte unerlässlich. Im CD-A Experiment im Felslabor Mont Terri (Schweiz) werden vergleichende Untersuchun-gen in zwei Nischen mit verschiedenen klimatischen Bedingungen durchgeführt: Während das Verhalten der einen Nische durch Entsättigungseffekte gekennzeichnet ist, werden diese Effekte in der anderen Nische soweit wie möglich vermieden. Ein komplexes Messprogramm sowie begleitende numerische Simulationen (OGS, CodeBright) untersuchen den Einfluss der Luftfeuchte auf das saisonale und langfris-tige Verformungsverhalten.

The continental tropics play a leading role in the terrestrial energy, water, and carbon cycles. Land–atmosphere interactions are integral in the regulation of these fluxes across multiple spatial and temporal scales over tropical continents. We review here some of the important characteristics of tropical continental climates and how land–atmosphere interactions regulate them. Along with a wide range of climates, the tropics manifest a diverse array of land–atmosphere interactions. Broadly speaking, in tropical rainforest climates, light and energy are typically more limiting than precipitation and water supply for photosynthesis and evapotranspiration (ET), whereas in savanna and semi-arid climates, water is the critical regulator of surface fluxes and land–atmosphere interactions. We discuss the impact of the land surface, how it affects shallow and deep clouds, and how these clouds in turn can feed back to the surface by modulating surface radiation and precipitation. Some results from recent research suggest that shallow clouds may be especially critical to land–atmosphere interactions. On the other hand, the impact of land-surface conditions on deep convection appears to occur over larger, nonlocal scales and may be a more relevant land–atmosphere feedback mechanism in transitional dry-to-wet regions and climate regimes.