ALBERT

Description: Digitalisation has transformed the way we communicate and collaborate with friends, family, and colleagues. In a similar vein, digitalisation in industry – the so-called industry 4.0 – is expected to transform the way firms and their suppliers collaborate in global supply chains. Considering that 25 percent of global emissions in 2021 were generated by industry (IEA): Can industry 4.0 play a role in greening industrial supply chains? Researchers at the Research Institute for Sustainability (RIFS) at the Helmholtz Centre Potsdam explored the opportunities and risks of digital supply chains for environmental sustainability. In short: sustainability does not simply occur as a by-product of digitalization. Firms should aim to increase sustainability levels in their supply chain – whether through digital or non-digital means.

Description: What to expect of the incoming Lula government’s environmental policy

Description: As we start off the new year and set our sights on new goals and projects, we also want to take stock of the many activities and achievements of the RIFS “Justice in Sustainability” focal topic team during 2022.

Description: The term “triple crisis” loomed large in 2022: The interlinking crises of the pandemic, the climate and energy crises, and the war in Ukraine took many people to their existential limits this past year. Geopolitically, we now face a fragmented world in which power relations are increasingly contested. This was evident at the Sharm el-Sheikh Climate Change Conference (COP 27) in November, where familiar lines of conflict shaped negotiations. Tensions between countries of the Global North and South, for example: Who bears how much responsibility for the climate change that is already occurring (not least of all financial responsibility!) and who (still) counts as a developing country and should be granted support? Debate also continues to rage around the exploitation and use of fossil fuels, which many countries wish to continue for as long as possible – even under the Paris Agreement.

Description: Let's close our eyes for a moment and travel back in time to childhood. Try to remember a time when you felt scared or devastated, the feeling of losing someone you truly love. And now, let’s imagine that these moments begin to multiply and persist. They stay in our minds for days and weeks.

Description: For years now the international community has been negotiating an agreement that will cover more than half of the Earth's surface and establish rules for the conservation and sustainable use of marine biodiversity. Will they succeed?

Description: research

Description: research

Description: Why is it important to go to the major expense and long-term effort of organizing, preparing and executing drilling in the permanently ice-covered, deep-sea regions of the Arctic? Because of its unique characteristics, the Arctic Ocean has a climatic and oceanographic influence far beyond its limited geographic extent. For example, deep water formed in the polar and subpolar seas fills the basins of the rest of the world's ocean. The modern Arctic sea ice cover, although apparently thermodynamically unstable, has existed for severul million years, affecting global heat budgets and therefore the global climate system. Yet we do not know when deep waters of the Arctic Ocean were first linked with those of the Norwegian-Greenland Sea, nor when sea ice first covered the Arctic Basin. Likewise the geologic composition and history of major morphologic features, ridges, plateaus and margins are practically unknown. This knowledge is missing because of a lack of appropriate samples of sediment and bedrock. With a coordinated effort of site surveying and drilling in the Arctic it would be feasible to obtain the required material. This report presents a scientific rationale and an organizational scheme together with various technological options for drilling in this hostile environment.

Description: Viscosity in the momentum equation is needed for numerical stability, as well as to arrest the direct cascade of enstrophy at grid scales. However, a viscous momentum closure tends to over-dissipate eddy kinetic energy. To return excessively dissipated energy to the system, the viscous closure is equipped with what is called dynamic kinetic energy backscatter. The amplitude of backscatter is based on the amount of unresolved kinetic energy (UKE). This energy is tracked through space and time via a prognostic equation. Our study proposes to add advection of UKE by the resolved flow to that equation to explicitly consider the effects of nonlocality on the subgrid energy budget. UKE can consequently be advected by the resolved flow before it is reinjected via backscatter. Furthermore, we suggest incorporating a stochastic element into the UKE equation to account for missing small-scale variability, which is not present in the purely deterministic approach. The implementations are tested on two intermediate complexity setups of the global ocean model FESOM2: an idealized channel setup and a double-gyre setup. The impacts of these additional terms are analyzed, highlighting increased eddy activity and improved flow characteristics when advection and carefully tuned, stochastic sources are incorporated into the UKE budget. Additionally, we provide diagnostics to gain further insights into the effects of scale separation between the viscous dissipation operator and the backscatter operator responsible for the energy injection. Oceanic swirls or "eddies" have a typical size of 10-100 km, which is close to the smallest scales that global ocean models commonly resolve. For physical and numerical reasons, these models require the addition of artificial terms that influence the flow near its smallest scales. Common approaches have the drawback of introducing systematic loss of kinetic energy contained in the eddies, which leads to errors that also affect the oceanic circulation on global scales. In our research, we compensate for this error by returning some of the missing energy back into the simulation, using a so-called kinetic energy backscatter scheme. In this work, we continue the development of an already existing and successful backscatter scheme, adding certain improvements to the way energy is budgeted and returned to the flow: we ensure that the local energy budget is attached to each fluid parcel as it is transported by the large-scale flow, and we also add a random forcing term that mimics unknown sources of such energy to bring its statistical properties closer to reality. We demonstrate that these modifications effectively improve the characteristics of the simulated flow. Extension of the subgrid energy equation of the kinetic energy backscatter parameterization by adding advection and a stochastic term Both additional terms improve several flow characteristics in two idealized test cases, a channel and a double-gyre Scale analysis reveals the necessity of sufficient scale separation between viscous energy dissipation and energy injection via backscatter. Key Points: - Extension of the subgrid energy equation of the kinetic energy backscatter parameterization by adding advection and a stochastic term - Both additional terms improve several flow characteristics in two idealized test cases, a channel and a double-gyre - Scale analysis reveals the necessity of sufficient scale separation between viscous energy dissipation and energy injection via backscatter

Description: The simulation of deep-sea conditions in laboratories is technically challenging but necessary for experiments that aim at a deeper understanding of physiological mechanisms or host-symbiont interactions of deep-sea organisms. In a proof-of-concept study, we designed a recirculating system for long-term culture (〉2 yr) of deep-sea mussels Gigantidas childressi (previously Bathymodiolus childressi). Mussels were automatically (and safely) supplied with a maximum stable level of ~60 μmol L−1 methane in seawater using a novel methane–air mixing system. Experimental animals also received daily doses of live microalgae. Condition indices of cultured G. childressi remained high over the years, and low shell growth rates could be detected, too, which is indicative of positive energy budgets. Using stable isotope data, we demonstrate that G. childressi in our culture system gained energy, both, from the digestion of methane-oxidizing endosymbionts and from digesting particulate food (microalgae). Limitations of the system, as well as opportunities for future experimental approaches involving deep-sea mussels, are discussed.

Description: The presented pilot for the Synthesis Product for Ocean Time Series (SPOTS) includes data from 12 fixed ship-based time-series programs. The related stations represent unique open-ocean and coastal marine environments within the Atlantic Ocean, Pacific Ocean, Mediterranean Sea, Nordic Seas, and Caribbean Sea. The focus of the pilot has been placed on biogeochemical essential ocean variables: dissolved oxygen, dissolved inorganic nutrients, inorganic carbon (pH, total alkalinity, dissolved inorganic carbon, and partial pressure of CO2), particulate matter, and dissolved organic carbon. The time series used include a variety of temporal res- olutions (monthly, seasonal, or irregular), time ranges (10–36 years), and bottom depths (80–6000 m), with the oldest samples dating back to 1983 and the most recent one corresponding to 2021. Besides having been harmo- nized into the same format (semantics, ancillary data, units), the data were subjected to a qualitative assessment in which the applied methods were evaluated and categorized. The most recently applied methods of the time- series programs usually follow the recommendations outlined by the Bermuda Time Series Workshop report (Lorenzoni and Benway, 2013), which is used as the main reference for “method recommendations by prevalent initiatives in the field”. However, measurements of dissolved oxygen and pH, in particular, still show room for improvement. Additional data quality descriptors include precision and accuracy estimates, indicators for data variability, and offsets compared to a reference and widely recognized data product for the global ocean: the GLobal Ocean Data Analysis Project (GLODAP). Generally, these descriptors indicate a high level of continuity in measurement quality within time-series programs and a good consistency with the GLODAP data product, even though robust comparisons to the latter are limited. The data are available as (i) a merged comma-separated file that is compliant with the World Ocean Circulation Experiment (WOCE) exchange format and (ii) a format dependent on user queries via the Environmental Research Division’s Data Access Program (ERDDAP) server of the Global Ocean Observing System (GOOS). The pilot increases the data utility, findability, accessibility, interoperability, and reusability following the FAIR philosophy, enhancing the readiness of biogeochemical time series. It facilitates a variety of applications that benefit from the collective value of biogeochemical time-series observations and forms the basis for a sustained time-series living data product, SPOTS, complementing relevant products for the global interior ocean carbon data (GLobal Ocean Data Analysis Project), global surface ocean carbon data (Surface Ocean CO2 Atlas; SOCAT), and global interior and surface methane and nitrous oxide data (MarinE MethanE and NiTrous Oxide product). Aside from the actual data compilation, the pilot project produced suggestions for reporting metadata, im- plementing quality control measures, and making estimations about uncertainty. These recommendations aim to encourage the community to adopt more consistent and uniform practices for analysis and reporting and to update these practices regularly. The detailed recommendations, links to the original time-series programs, the original data, their documentation, and related efforts are available on the SPOTS website. This site also pro- vides access to the data product (DOI: https://doi.org/10.26008/1912/bco-dmo.896862.2, Lange et al., 2024) and ancillary data.

Description: The sinking of particulate matter from the upper ocean dominates the export and sequestration of organic carbon by the biological pump, a critical component of the Earth's carbon cycle. Controls on carbon export are thought to be driven by ecological processes that produce and repackage sinking biogenic particles. Here, we present observations during the demise of the Northeast Atlantic Ocean spring bloom illustrating the importance of storm-induced turbulence on the dynamics of sinking particles. A sequence of four large storms caused upper layer mean turbulence levels to vary by more than three orders of magnitude. Large particle (>0.1 to 10 mm) abundance and size changed accordingly: increasing via shear coagulation when turbulence was moderate and decreasing rapidly when turbulence was intense due to shear disaggregation. Particle export was also tied to storm forcing as large particles were mixed to depth during mixed layer deepening. After the mixed layer shoaled, these particles, now isolated from intense surface mixing, grew larger and subsequently sank. This sequence of events matched the timing of sinking particle flux observations. Particle export was influenced by increases in aggregate abundance and porosity, which appeared to be enhanced by the repeated creation and destruction of aggregates. Last, particle transit efficiency through the mesopelagic zone was reduced by presumably biotic processes that created small particles (〈0.5 mm) from larger ones. Our results demonstrate that ocean turbulence significantly impacts the nature and dynamics of sinking particles, strongly influencing particle export and the efficiency of the biological pump.

Description: The marine cyanobacterium Trichodesmium has the remarkable ability to interact with and utilize air‐borne dust as a nutrient source. However, dust may adversely affect Trichodesmium through buoyancy loss and exposure to toxic metals. Our study explored the effect of desert dust on buoyancy and mortality of natural Red Sea puff‐shaped Trichodesmium thiebautii . Sinking velocities and ability of individual colonies to stay afloat with increasing dust loads were studied in sedimentation chambers. Low dust loads of up to ∼400 ng per colony did not impact initial sinking velocity and colonies remained afloat in the chamber. Above this threshold, sinking velocity increased linearly with the colony dust load at a slope matching prediction based on Stoke's law. The potential toxicity of dust was assessed with regards to metal dissolution kinetics, differentiating between rapidly released metals, which may impact surface blooms, and gradually released metals that may impact dust‐centering colonies. Incubations with increasing dust concentrations revealed colony death, but the observed lethal dose far exceeded dust concentrations measured in coastal and open ocean systems. Removal of toxic particles as a mechanism to reduce toxicity was explored using SEM‐EDX imaging of colonies incubated with Cu‐minerals, yet observations did not support this pathway. Combining our current and former experiments, we suggest that in natural settings the nutritional benefits gained by Trichodesmium via dust collection outweigh the risks of buoyancy loss and toxicity. Our data and concepts feed into the growing recognition of the significance of dust for Trichodesmium 's ecology and subsequently to ocean productivity. Plain Language Summary Trichodesmium spp. are abundant cyanobacteria, forming extensive blooms in low latitude warm oceans, and contribute significantly to carbon (C) and nitrogen (N) fixation, recycling and export. Desert dust deposited on the ocean surface was shown to supply Trichodesmium with the scarce micronutrient iron. Spherical, millimeter‐sized colonies of Trichodesmium from different ocean basins were reported to actively accumulate dust in their cores. While dust accumulation likely helps Trichodesmium obtain nutrients, it may come at a cost. Metals released from dust may induce toxicity and the dust weight could send Trichodesmium to the ocean depth. Our experimental study with natural Red Sea colonies examined some trade‐offs of dust accumulation. Links between dust load and colony buoyancy were examined in sedimentation experiments. Toxicity thresholds for surface blooms and dust‐accumulating colonies were determined from mortality assays and dust dissolution measurements. We found that metal‐induced toxicity to Trichodesmium is unlikely at typical oceanic dust fluxes, and that dust‐containing colonies can remain buoyant. At high loads, dust weight determined the colony's sinking velocity. Our findings and concepts can be extended to additional aerosols and Trichodesmium ‐rich habitats, and may assist in assessing Trichodesmium 's distribution, ecophysiology, and contribution to C or N transport to the deep ocean. Key Points Dust collected by Trichodesmium colonies from seawater as a nutrient source may result in metal toxification and buoyancy loss At moderate dust loads, colonies kept their buoyancy, but above 400 ng, sinking velocities increased linearly with dust loads Desert dust induced Trichodesmium mortality through toxic metal release, yet the lethal dose far exceeded oceanic dust concentrations

Description: The field of oceanography is transitioning from data-poor to data-rich, thanks in part to increased deployment of in-situ platforms and sensors, such as those that instrument the US-funded Ocean Observatories Initiative (OOI). However, generating science-ready data products from these sensors, particularly those making biogeochemical measurements, often requires extensive end-user calibration and validation procedures, which can present a significant barrier. Openly available community-developed and -vetted Best Practices contribute to overcoming such barriers, but collaboratively developing user-friendly Best Practices can be challenging. Here we describe the process undertaken by the NSF-funded OOI Biogeochemical Sensor Data Working Group to develop Best Practices for creating science-ready biogeochemical data products from OOI data, culminating in the publication of the GOOS-endorsed OOI Biogeochemical Sensor Data Best Practices and User Guide. For Best Practices related to ocean observatories, engaging observatory staff is crucial, but having a “user-defined” process ensures the final product addresses user needs. Our process prioritized bringing together a diverse team and creating an inclusive environment where all participants could effectively contribute. Incorporating the perspectives of a wide range of experts and prospective end users through an iterative review process that included “Beta Testers’’ enabled us to produce a final product that combines technical information with a user-friendly structure that illustrates data analysis pipelines via flowcharts and worked examples accompanied by pseudo-code. Our process and its impact on improving the accessibility and utility of the end product provides a roadmap for other groups undertaking similar community-driven activities to develop and disseminate new Ocean Best Practices.

Description: We present a continuous ∼6.2 Ma long record of explosive activity from the Northwest Pacific volcanic arcs based on a composite tephra sequence derived from Ocean Drilling Program Sites 882A and 884B, and core MD01‐2416 on the Detroit Seamount. Geochemical fingerprinting of tephra glass using major and trace element analyses and correlations of tephra layers between the three cores allowed the identification of 119 unique tephras, suggesting eruptions of magnitude (M) of 5.8–7.8. Age estimates for all the identified eruptions were obtained with the help of published and further refined age models for the studied cores, direct 40 Ar/ 39 Ar dating of four ash layers, and Bayesian age modeling. The glass compositions vary from low‐ to high‐K 2 O basaltic andesite to rhyolite and exhibit typical subduction‐related affinity. The majority of the tephras originated from Kamchatka, only a few tephras—from the neighboring Kuril and Aleutian arcs. The glass compositions revealed no temporal trends but made it possible to identify their source volcanic zones in Kamchatka and, in some cases, to determine their source eruptive centers. Our data indicates episodes of explosive activity recorded in the Detroit tephra sequence at ∼6,200, 5,600–5,000, 4,300–3,700 ka, and almost continuous activity since ∼3,000 ka. Within the latter episode, the most active intervals can be identified at 1,700–1,600, 1,150–1,050, and 600–50 ka. Geochemically fingerprinted and dated Detroit tephra sequence form a framework for dating and correlating diverse paleoenvironmental archives across the Northwest Pacific and for studies of geochemical evolution of the adjacent volcanic arcs. Plain Language Summary Explosive volcanic eruptions produce defragmented material named tephra, which can be spread over large distances and form layers in sediments on ocean floor and continents. Long continuous tephra sequences preserved in marine sediments provide one of the best chronicles of the explosive eruptions, and allow detailed evaluation of their timing relative to climatic changes. We studied one of such natural records of explosive volcanism preserved in the sediments covering the Detroit Seamount in the Northwest Pacific. We identified 119 tephra layers, which have been buried in the sediments during the last 6.2 Ma and represent volcanic eruptions with ≥7 km 3 tephra volume. We analyzed geochemical composition and determined age of each tephra. Most tephras were found to originate from volcanoes in Kamchatka, a few from the Kuril and Aleutian volcanoes. We found that the explosive activity recorded in the Detroit tephra sequence was not uniform over time. It peaked at ∼6,200, 5,600–5,000, 4,300–3,700, has continued since ∼3,000 thousand years ago until present. All tephra layers from our study can be used as unique isochrons for dating and correlating paleoenvironmental archives across the Northwest Pacific and for the reconstruction of the detailed volcanic record in the Earth history. Key Points We report age and composition for 119 tephras from sediment cores representing ∼6.2 Ma record of explosive volcanism in the NW Pacific The tephras have subduction‐related origin and mostly originate from volcanic eruptions with magnitude (M) of 5.8–7.8 in Kamchatka The data indicates episodes of explosive activity at ∼6,200, 5,600–5,000, 4,300–3,700 ka, and almost continuous activity since ∼3,000 ka

Description: Strategies for mitigating climate change today include plans for removing carbon dioxide from the atmosphere through “Negative Emissions Technologies” (NETs). NETs create new opportunities for scientific research, technology development, and the development of financial products, but also new conceptual possibilities, for example of declaring one’s ambition to become “climate neutral.” NETs thus constitute a novel frontier in climate science and politics whose conditions of possibility, characteristics, and consequences can be studied by social scientists and humanists. For environmental sociologists, NETs pose numerous opportunities for engaging with questions around future-making, imaginaries, promises, expertise, markets, infrastructure, justice, publics, and generally, the shape and role of science and technology in a form of social life that is increasingly organized around “planetary” concepts.

Description: CrossGov D2.1 EU and international policy landscape - Mapping EU policies and Green Deal objectives: general observations for policy coherence in the marine domain aims to provide a mapping of the European Green Deal policy landscape relevant to the marine domain and the CrossGov project. It also offers a general introduction into how policy coherence, embedded within the design of (selected) EU policies, supports or impedes progress towards the EGD’s objectives in the marine domain. A total of 36 policies were selected and mapped against five EGD strategies, namely the 2030 Climate Target Plan, the EU Climate Change Adaptation Strategy, the Biodiversity Strategy for 2030, the Zero Pollution Action Plan, and the Sustainable Blue Economy Strategy. These five strategies lay out a total of 25 specific objectives to implement the vision of the EGD, identified as relevant to the marine domain and the focus of the CrossGov project – i.e. climate change, biodiversity loss, and pollution.

Description: Die Bestimmung der Temperaturverteilung in der Erdkruste und im oberen Erdmantel ist von großer Bedeutung für die Behandlung geotektonischer Probleme. In dieser Arbeit wird die Temperaturverteilung längs eines Profils in Süditalien untersucht, das vom Südadriatischen Meer durch Kalabrien zum Tyrrhenischen Meer verläuft. Grundlage für diese Untersuchung bilden eine Anzahl publizierter Wärmeflußwerte und ein refraktionsseismisches Profil. Längs des ausgewählten geothermischen Profils sind die Temperatur-Tiefen-Funktionen für zwei Modelle der Wärmeproduktionsverteilung, Schichten- und Exponential-Modell , für den stationären Zustand berechnet worden.

Description: The determination of temperature distribution in the earth's crust and upper mantle is of great importance for geotectonic problems. The temperature distribution is discussed along a profile in southern Italy, which runs from the Adriatic to the Tyrrhenian Seas. This study is based on published heat flow values and seismic refraction data. The temperature-depth-functions are calculated for layer and exponential models for the heat production assuming a stationary state.

Description: thesis

Description: DFG, SUB Göttingen

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Vegetation classification is an essential prerequisite for understanding vegetation‐water relations at a range of spatial scales. However, in site‐specific applications, such classifications were mostly based on a single Unmanned Aerial Vehicle (UAV) flight, which can be challenging in grasslands and/or herbaceous‐dominated systems, as those communities are small in size and highly mixed. Here, we conducted monthly UAV flights for two years in a riparian wetland in Germany, with acquired imagery used for vegetation classification on a monthly basis under different strategies (with or without auxiliary information from other flights) to increase understanding in ecohydrology. The results show that multi‐flight‐based classification outperformed single‐flight‐based classification due to the higher classification accuracy. Moreover, improved sensitivity of temporal changes in community distribution highlights the benefits of multi‐flight‐based classification ‐ providing a more comprehensive picture of community evolution. From reference to the monthly community distribution, we argue that a combination of two or three flights in early‐ and late‐summer is enough to achieve comparable results to monthly flights, while mid‐summer would be a better timing in case only one flight is scheduled. With such detailed vegetation mapping, we further interpreted the complex spatio‐temporal heterogeneity in NDVI and explored the dominant areas and developmental progress of each community. Impacts from management (mowing events) were also evaluated based on the different responses between communities in two years. Finally, we explored how such vegetation mapping could help understand landscape ecohydrology, and found that the spatio‐temporal distribution of minimal soil moisture was related to NDVI peaks of local community, while grass distribution was explained by both topography and low moisture conditions. Such bi‐directional relationships proved that apart from contributing to an evidence base for wetland management, multi‐flight UAV vegetation mapping could also provide fundamental insights into the ecohydrology of wetlands.〈/p〉

Description: Chinese Scholarship Council (CSC)

Description: Einstein Foundation Berlin and Berlin University Alliance

Description: Leverhulme Trust http://dx.doi.org/10.13039/501100000275

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉To evaluate how the presence of pseudotachylytes affects the strength of crustal rocks, deformed pseudotachylytes and their relationship with pristine pseudotachylytes at the base of the Silvretta nappe are analyzed. Pseudotachylytes formed associated with high‐stress crystal plasticity (〈italic〉σ〈/italic〉〈sub〉〈italic〉d〈/italic〉〈/sub〉 > 400 MPa), as indicated by twinned amphiboles in gneisses. Mylonitic quartz clasts enclosed within deformed pseudotachylytes and mylonitic vein‐quartz, hosting folded pseudotachylyte injection veins, reflect creep at lower stresses (ca. 100 MPa) after seismic rupturing. Deformed pseudotachylytes can be crosscut by pristine pseudotachylytes, indicating a second, independent stage of coseismic rupturing after creep. The evidence of dynamic dislocation creep of quartz and the presence of stilpnomelane and epidote associated with all fault rocks indicate similar ambient greenschist facies conditions during all deformation stages. Whereas the intermediate stage of creep is interpreted to represent deformation at large distance to the propagating thrust tip, the pristine pseudotachylytes represent the last stage of rupturing eventually leading to nappe decoupling from its basement. Gneiss clasts in an ultramylonitic matrix (i.e., deformed pseudotachylyte) reveal that pseudotachylytes have a lower strength during creep in relation to the hosting gneisses. In contrast, during coseismic high‐stress crystal plasticity, the coarse gneisses accumulate a higher amount of strain. This strength‐relationship explains that only those rocks rupture, which have not been previously deformed before. The study demonstrates the importance of different strengths of crustal rocks at specific stress‐ and strain‐rate conditions in dependence on the distance to the propagating fault tip.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉Ultramylonites (deformed pseudotachylytes) and mylonites represent creep at large distance to the propagating thrust tip〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Pristine pseudotachylytes represent final deformation at the tip of the propagating thrust fault associated with nappe decoupling〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Pseudotachylytes are weak during aseismic creep and strong during coseismic high‐stress plasticity〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: https://doi.org/10.17632/xhh2ktks9g.4

Description: https://nano.oxinst.com/products/aztec/

Description: https://www.horiba.com/aut/scientific/products/detail/action/show/Product/labspec-6-spectroscopy-suite-software-1843/

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉There have been a number of theories proposed concerning the loss of relativistic electrons from the radiation belts. However, direct observations of loss were not possible on a number of previous missions due to the large field of view of the instruments and often high‐altitude orbits of satellites that did not allow researchers to isolate the precipitating electrons from the stably trapped. We use measurements from the ELFIN‐L suit of instruments flown on Lomonosov spacecraft at LEO orbit, which allows us to distinguish stably trapped from the drift loss cone electrons. The sun‐synchronous orbit of Lomonosov allows us to quantify scattering that occurred into the loss cone on the dawn‐side and the dusk‐side magnetosphere. The loss at MeV energies is observed predominantly on the dawn‐side, consistent with the loss induced by the chorus waves. The companion data publication provides processed measurements.〈/p〉

Description: Plain Language Summary: There have been a number of models proposed concerning the loss of relativistic electrons from radiation belts. However, the direct observations of loss have been missing, as for most of the previous missions; the large aperture telescopes could not isolate the precipitating electrons from being stably trapped. In this study, we use measurements from ELFIN‐L on Lomonosov that allow for such separation and allow us to distinguish stably trapped from precipitating particles. We can also identify the particles that will be lost within one drift around the Earth, the so‐called drift loss cone. For understanding the loss processes and differentiating between them, it's crucially important to quantify where in local magnetic time these electrons will be scattered into the drift loss cone. Measurements from the ELFIN‐L instrument show that the loss at MeV energies is observed predominantly on the dawn side, consistent with the loss induced by the so‐called chorus plasma waves.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉ELFIN‐L measurements allow comparing scattering into the loss cone on the dawn and dusk side〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Processed Level‐3 measurements are provided in the data publication〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Most of the relativistic electrons are scattered into the drift loss cone on the dawn side〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: National Science Foundation

Description: Russian University Satellite Mission

Description: Helmholtz Association

Description: European Union's Horizon 2020 Research and Innovation Program

Description: https://doi.org/10.5880/GFZ.2.7.2023.002

Description: https://doi.org/10.5880/GFZ.2.7.2023.003

Description: https://doi.org/10.5880/GFZ.2.7.2023.004

Description: https://doi.org/10.5880/GFZ.2.7.2023.005

Description: https://doi.org/10.5880/GFZ.2.7.2023.006

Description: https://doi.org/10.5880/GFZ.2.7.2023.007

Description: https://www.ncei.noaa.gov/data/poes-metop-space-environment-monitor/access/l1b/v01r00/

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Mercury is the smallest and innermost planet of our solar system and has a dipole‐dominated internal magnetic field that is relatively weak, very axisymmetric and significantly offset toward north. Through the interaction with the solar wind, a magnetosphere is created. Compared to the magnetosphere of Earth, Mercury's magnetosphere is smaller and more dynamic. To understand the magnetospheric structures and processes we use in situ MESSENGER data to develop further a semi‐empiric model of the magnetospheric magnetic field, which can explain the observations and help to improve the mission planning for the BepiColombo mission en‐route to Mercury. We present this semi‐empiric KTH22‐model, a modular model to calculate the magnetic field inside the Hermean magnetosphere. Korth et al. (2015, 〈ext-link ext-link-type="uri" xlink:href="https://doi.org/10.1002/2015JA021022"〉https://doi.org/10.1002/2015JA021022〈/ext-link〉, 2017, 〈ext-link ext-link-type="uri" xlink:href="https://doi.org/10.1002/2017gl074699"〉https://doi.org/10.1002/2017gl074699〈/ext-link〉) published a model, which is the basis for the KTH22‐model. In this new version, the representation of the neutral sheet current magnetic field is more realistic, because it is now based on observations rather than ad‐hoc assumptions. Furthermore, a new module is added to depict the eastward ring shaped current magnetic field. These enhancements offer the possibility to improve the main field determination. In addition, analyzing the magnetic field residuals allows us to investigate the field‐aligned currents and their possible dependencies on external drivers. We see increasing currents under more disturbed conditions inside the magnetosphere, but no clear dependence on the z‐component of the interplanetary magnetic field nor on the magnetosheath plasma 〈italic〉β〈/italic〉.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉We present a revised model of Mercury's magnetospheric magnetic field〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉The model now includes an eastward ring shaped current and the neutral sheet current is calculated more precisely with Biot Savart's law〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉The strength of the field‐aligned currents increases with higher magnetic activity〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: German Ministerium für Wirtschaft und Klimaschutz and the German Zentrum für Luft‐ und Raumfahrt

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: ESA Research Fellowship

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Recent observations and modeling increasingly reveal the key role of cold pools in organizing the convective cloud field. Several methods for detecting cold pools in simulations exist, but are usually based on buoyancy fields and fall short of reliably identifying the active gust front. The current cold pool (CP) detection and tracking algorithm (CoolDeTA), aims to identify cold pools and follow them in time, thereby distinguishing their active gust fronts and the “offspring” rain cells generated nearby. To accomplish these tasks, CoolDeTA utilizes a combination of thermodynamic and dynamical variables and examines the spatial and temporal relationships between cold pools and rain events. We demonstrate that CoolDeTA can reconstruct CP family trees. Using CoolDeTA we can contrast radiative convective equilibrium (RCE) and diurnal cycle CP dynamics, as well as cases with vertical wind shear and without. We show that the results obtained are consistent with a conceptual model where CP triggering of children rain cells follows a simple birth rate, proportional to a CP's gust front length. The proportionality factor depends on the ambient atmospheric stability and is lower for RCE, in line with marginal stability as traditionally ascribed to the moist adiabat. In the diurnal case, where ambient stability is lower, the birth rate thus becomes substantially higher, in line with periodic insolation forcing—resulting in essentially run‐away mesoscale excitations generated by a single parent rain cell and its CP.〈/p〉

Description: Plain Language Summary: Cold pools are cooled air masses below thunderstorm clouds, produced when rain evaporates underneath such clouds. Cold pools are important, as they produce strong gusts and have been associated with clumping of rain cells, whereby heavy rainfall over relatively small areas could be generated—with implications for flooding. The current work describes a method that helps identify such cold pools in computer simulation data. In contrast to earlier methods, we here show that the interaction between a CP and its surroundings can be reconstructed by the method. We show that this identification works under a range of contexts, such as when horizontal wind is applied in the simulations or when the surface temperature is not constant—as might often be the case over a land surface. The identification reveals interesting dynamical effects, such as that in some cases, cold pools can kick‐start a form of chain reaction, by which “rain cell children” of it give rise to additional cold pools that again produce children, and so forth. The dynamics revealed is in line with expectations of widespread, so‐called mesoscale convective systems over land, whereas over an ocean surface the dynamics is much less explosive.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉Our CoolDeTA algorithm reliably detects and tracks cold pools and their causal chains〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉We propose a simple conceptual model which reproduces the cascade‐like mesoscale cold pool dynamics identified by CoolDeTA〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉CoolDeTA opens for new studies into the dynamics of convective self‐organization through cold pools〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: Villum Fonden http://dx.doi.org/10.13039/100008398

Description: European Research Council http://dx.doi.org/10.13039/501100000781

Description: Novo Nordisk Foundation Interdisciplinary Synergy Program

Description: Scientific Steering Committee

Description: https://doi.org/10.5281/zenodo.6513224

Description: https://github.com/Shakiro7/coldPool-detection-and-tracking

Description: https://doi.org/10.5281/zenodo.10115957

Description: https://doi.org/10.7717/peerj.453

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉The seasonal deposition and sublimation of CO〈sub〉2〈/sub〉 constitute a major element in the Martian volatile cycle. Here, we propose to use the shadow variations of the ice blocks at the foot of the steep scarps of the North Polar Layered Deposits (NPLD) to infer the vertical evolution of the seasonal deposits. We conduct an experiment at a steep scarp centered at (85.0°N, 151.5°E). We assume that no snowfall remains on top of the selected ice blocks, the frost ice layer is homogeneous around the ice blocks and their surroundings, and no significant moating is present. We show that the average thickness of the seasonal deposits due to snowfalls in Mars Year 31 is 0.97 ± 0.13 m at Ls = 350.7° in late winter. The large depth measured makes us wonder if snowfalls are more frequent and violent than previously thought. Meanwhile, we show that the average frost thickness in Mars Year 31 reaches 0.64 ± 0.18 m at Ls = 350.7° in late winter. Combined, the total thickness of the seasonal cover in Mars Year 31 reaches 1.63 ± 0.22 m at Ls = 350.7° in late winter, continuously decreases to 0.45 ± 0.06 m at Ls = 42.8° in middle spring and 0.06 ± 0.05 m at Ls = 69.6° in late spring. These estimates are up to 0.8 m lower than the existing Mars Orbiter Laser Altimeter results during the spring. Meanwhile, we observe that snow in the very early spring of Mars Year 36 can be 0.36 ± 0.13 m thicker than that in Mars Year 31. This study demonstrates the dynamics of the Martian climate and emphasizes the importance of its long‐term monitoring.〈/p〉

Description: Plain Language Summary: Like Earth, Mars also has seasons. Up to one third of the atmospheric CO〈sub〉2〈/sub〉 annually exchanges with the polar surface through seasonal deposition/sublimation processes. Deposition can be either atmospheric precipitation as snowfall or direct surface condensation as frost. At the steep scarps of the North Polar Layered Deposits (NPLD), fractured ice fragments can detach and fall to form ice blocks. We propose to use variations in the shadows of these ice blocks, observed in the High Resolution Imaging Science Experiment images, to infer the thickness evolution of the seasonal deposits. We make reasonable assumptions about the distribution of snowfall and frost around the ice blocks and their surroundings, which allow us to separately measure the thickness of snowfall and frost. Meanwhile, we introduce a novel approach that allows us to estimate the thickness of the seasonal deposits during late winter and early spring when image quality is insufficient. This approach also enables us to peer into the interannual thickness variations of snowfall. We carry out a successful experiment at a scarp centered at (85.0°N, 151.5°E). The obtained thickness measurements demonstrate the dynamics of the Martian volatile cycling and can be used to constrain the Martian climate models.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉We propose to examine the shadow variations of the ice blocks at the Martian polar region to infer the thickness of the seasonal deposits〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Maximum thickness of the seasonal deposits at the study scarp in MY31 is 1.63 ± 0.22 m to which snowfalls contribute 0.97 ± 0.13 m〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Seasonal deposits at the study scarp are up to 0.8 m shallower than previous measurements during spring〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: HX, LML, and PJG

Description: https://doi.org/10.17189/1520303

Description: https://doi.org/10.17632/5yy475dbry.1

Description: https://doi.org/10.17632/x953mzxxvv.1

Description: https://doi.org/10.17189/1520101

Description: http://www.msss.com/moc_gallery/2001

Description: 〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉〈italic〉INSIGHT〈/italic〉 is a Python‐based software tool for processing and reducing 2D grazing‐incidence wide‐ and small‐angle X‐ray scattering (GIWAXS/GISAXS) data. It offers the geometric transformation of the 2D GIWAXS/GISAXS detector image to reciprocal space, including vectorized and parallelized pixel‐wise intensity correction calculations. An explicit focus on efficient data management and batch processing enables full control of large time‐resolved synchrotron and laboratory data sets for a detailed analysis of kinetic GIWAXS/GISAXS studies of thin films. It processes data acquired with arbitrarily rotated detectors and performs vertical, horizontal, azimuthal and radial cuts in reciprocal space. It further allows crystallographic indexing and GIWAXS pattern simulation, and provides various plotting and export functionalities. Customized scripting offers a one‐step solution to reduce, process, analyze and export findings of large 〈italic〉in situ〈/italic〉 and 〈italic〉operando〈/italic〉 data sets.〈/p〉

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Dansgaard‐Oeschger (D‐O) climate variability during the last glaciation was first evidenced in ice cores and marine sediments, and is also recorded in various terrestrial paleoclimate archives in Europe. The relative synchronicity across Greenland, the North Atlantic and Europe implies a tight and fast coupling between those regions, most probably effectuated by an atmospheric transmission mechanism. In this study, we investigated the atmospheric changes during Greenland interstadial (GI) and stadial (GS) phases based on regional climate model simulations using two specific periods, GI‐10 and GS‐9 both around 40 ka, as boundary conditions. Our simulations accurately capture the changes in temperature and precipitation as reconstructed by the available proxy data. Moreover, the simulations depict an intensified and southward shifted eddy‐driven jet during the stadial period. Ultimately, this affects the near‐surface circulation toward more southwesterly and cyclonic flow in western Europe during the stadial period, explaining much of the seasonal climate variability recorded by the proxy data, including oxygen isotopes, at the considered proxy sites.〈/p〉

Description: Plain Language Summary: The climate during the last ice age varied between colder and warmer periods on timescales ranging from hundreds to thousands of years. This variability was first detected in Greenland ice cores and marine sediment cores of the North Atlantic, as well as in continental geological records in Europe. The variation between the colder and warmer periods occur mostly simultaneously in Greenland and in Europe, which is why the atmosphere is assumed to have an important role in transferring the climate signals. We simulated two different periods of the last ice age, one colder and one warmer around 40,000 years ago, using a regional climate model. The aim was to study how the climate and atmospheric circulation changed during these two periods. We find the eddy‐driven jet over the North Atlantic intensified and shifted southward during the colder period. The jet influences the near‐surface atmospheric circulation and leads to more southwesterly and cyclonic flow in western Europe. Oxygen isotope variations observed in western European paleoclimate records may be partly explained by different, more southern moisture sources on top of changes in seasonal temperatures.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉Simulated temperatures agree with proxy data; precipitation is biased but GI‐10 versus GS‐9 differences are well captured〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉The stadial winter jet stream is intensified and shifted southward, consistent with dominant southwesterly/cyclonic flow in western Europe〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Oxygen isotope signal changes at western European proxy sites may be explained not only by temperature but also by varying moisture sources〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: NRDIO

Description: AXA Research Fund http://dx.doi.org/10.13039/501100001961

Description: https://doi.org/10.5065/1dfh-6p97

Description: Geophysikalische Sensoren wie Erdgezeitengravimeter und Bohrlochneigungsmesser gehören zu den empfindlichsten mechanischen Meßgeräten, die gebaut werden. Sie zeichnen sich durch große Dynamik bei gleichzeitig extremer Breitbandigkeit aus. Vor allem diesen beiden Aspekten kann bei der konventionellen analogen Registrierung nicht immer Rechnung getragen werden. Deshalb wird mit dieser Arbeit die Einführung eines digitalen Registriersystems für diese Sensoren beschrieben, das moderne Konzepte der digitalen Datenerfassung und -Verarbeitung einsetzt. Bei zwei aktuellen Projekten in Skandinavien werden drei Askania Bohrlochneigungsmesser und ein LaCoste & Romberg Erdgezeitengravimeter betrieben. Bei der Installation in Norwegen geht es mit dem Einsatz von zwei Neigungsmessern um die Registrierung von Auflastsignalen durch einen Stausee und in Finnland soll mit der 3 Komponentenstation das gesamte Spektrum der Krustendynamik von Eigenschwingungen des Erdkörpers bis zu rezenten Deformationen auf gezeichnet werden. Es wird zunächst der Aufbau der Bohrlochneigungsmesser beschrieben und diskutiert, welche Signale in welchem Frequenzbereich gemessen werden können. Für die Vorbereitung dieser Arbeit wurden Modellrechnungen durchgeführt um über das tatsächliche Übertragungsverhalten im Bereich der Eigenperiode des Pendels mit und ohne Fesselung Auskunft zu erhalten. Die Überholung der Bohrlochneigungsmesser mit dem Ersatz des empfindlichen Original Vorverstärkers bilden den Abschluß der Pendelbeschreibung. Die Grundlagen des Meßprinzips der LaCoste & Romberg Gravimeter werden beschrieben und der analoge Eigenschwingungsfilter des Gravimeters untersucht. Für einen breitbandigen Datenkanal stellt sich bei einer Auflösung der Eigenschwingungssignale mit 72dB die Forderung nach einer Gesamtdynamik von 130dB. Bei der Darstellung der Grundlagen der digitalen Datenerfassung wird der Schwerpunkt auf die Beschreibung des Abtasttheorems gelegt und das Prinzip des Oversampling beschrieben. Die Umsetzung dieser Theorie in ein digitales Registriersystem mit einer Dynamik von 130dB bei einer Frequenzauflösung von .02 Hertz und dessen Einsatz im Gelände werden vorgestellt. Dabei wurde eine flexible Lösung gefunden, die sich ohne Probleme als Einkanalstation beim Gravimeter, oder als Mehrkanalsystem mit den Neigungsmessern konfigurieren läßt. Darüber hinaus werden zusätzliche Kanäle für meteorologischen Meßdaten bereitgestellt. Kurze Registrierbeispiele geben einen Eindruck von der Qualität der Rohdaten, und die Berechnung einiger Rauschspektren bestätigt, dass die geforderte Auflösung erreicht werden konnte. Beim Gravimeter konnten im Bereich von 102 bis 104 Sekunden

Description: Geophysical sensors like earth tide gravity meters and borehole tilt meters belong to the group of most sensitive mechanical devices, being available today. Their main features include wide dynamic range and extreme broadband resolution. These aspects are not always taken into consideration when dealing with analogue recording systems. Therefore, this work introduces a digital recording system for the above mentioned sensors which includes the modern concept of data acquisition and data processing. Within the scope of two projects being carried out in Scandinavia, three Askania borehole tilt meters and one LaCoste & Romberg earth tide gravity meter have been put into operation. In Norway two tilt meters are recording the loading signal of a reservoir. In Finland, a three component station is recording the whole spectrum of crusta dynamics, ranging from free mode signals of the earth to active crustal deformation. After the mechanical construction of the tilt meter has been discussed and the expected signal- and frequency range evaluated, model calculations are presented in order to determine the true transfer property of the pendulum around its natural resonance frequency. The introduction of an improved preamplifier stage for the borehole tilt meter then terminates the chapter on tilt meters. In the following the principle of operation of the LaCoste & Romberg gravity meter and the analogue free mode filter are being discussed in detail. For a broadband data stream dissolving the free mode signal at 72dB, the total dynamic range requires 130dB. For a broader understanding the basics of digital data acquisition, the sampling theorem and what is called oversampling are discussed in more detail. Furthermore, a digital recording system with a dynamic range of 130dB (at a frequency resolution of .02Hz) and its performance under field conditions is described. In conclusion, the configuration of the system as single channel station (gravity meter) or multichannel station (tilt meter) is demonstrated. In addition to the already existing data channels other channels are available to include meteorological data. Finally, a few original recordings are presented to demonstrate the quality of the raw data sets. The computation of the noise spectra shows, it was possible to achieve the necessary resolution. The noise amplitudes of the gravity meter at the range of 102 - 104 seconds were less than 2 ngal/√Hz and about 10 ngal/√Hz for the pendula.

Description: thesis

Description: DFG, SUB Göttingen

Description: Die Toskana ist die stärkste geothermische Anomalie auf dem europäischen Kontinent. In dieser Anomalie finden sich zahlreiche lokale geothermische Felder mit hoher Enthalpie, wie z.B. das Feld von Travale. In diesem geothermischen Feld, das im Era-Graben liegt, wurden in den Jahren 1980/81 elektromagnetische Messungen durchgeführt. Es war das Ziel der Untersuchungen, die Quelle und die Ursache dieser teilweise bekannten Anomalie zu finden. Hierzu sollte die Verteilung der elektrischen Leitfähigkeit in der Erdkruste bis in Tiefen der Kruste-Mantel-Grenze mit den Methoden der Magnetotellurik und Erdmagnetischen Tiefensondierung untersucht werden. Parallel dazu wurde die geothermische Anomalie von Travale mit einer Vielzahl weiterer elektromagnetischer, seismischer und geochemischer Methoden untersucht. Das Ziel, die geothermische Anomalie in der Erdkruste zu lokalisieren, war nicht einfach zu erreichen. Deshalb war es notwendig, ein Modell der Anomalie zu erarbeiten, aus dem die Lokalität folgen sollte. Vor angegangene elektromagnetische Untersuchungen (HAAK & SCHWARZ 1981) hatten gezeigt, daß nahezu das gesamte Gebiet der Toskana als eine Anomalie der elektrischen Leitfähigkeit anzusehen ist: Gutleitende Deckschichten, mit bis zu 10 km Mächtigkeit, werden von einem hochohmigen Basement unterlagert. An einigen Meßorten deutet sich der Übergangsbereich Kruste / Mantel - in einer Tiefe zwischen 20 und 30 km - durch eine Zone hoher Leitfähigkeit an. Dieser Bereich zeichnet sich durch Lamellen hoher und extrem niedriger seismischer Wellengeschwindigkeiten aus. Petrologisch kann dieses durch eine Wechsellagerung von basischem und saurem Material gedeutet werden. Die zeitlichen Variationen des elektrischen und magnetischen Feldes wurden im geothermischen Feld von Travale in einem breiten Periodenbereich von 6 - 10.000 s registriert. Die Meßorte liegen überwiegend auf zwei Profilen, eines verläuft parallel zum Era-Graben aus der Anomalie heraus nach NW, das zweite schneidet die Anomalie senkrecht zum Graben. Der Meßpunktabstand war mit einigen hundert Metern bis zu mehreren Kilometern sehr dicht, um möglichst alle lateralen Variationen der scheinbaren spezifischen Widerstände beobachten zu können. Es zeigte sich, daß die lateralen Variationen der spezifischen Widerstände im Gebiet von Travale sehr groß waren. Bis zu Perioden von 50-100 s ist der Era-Graben die dominierende zweidimensionale Leitfähigkeitsstruktur. Die gemessenen scheinbaren spezifischen Widerstände sind bei längeren Perioden durch dreidimensionale Leitfähigkeitsstrukturen verzerrt. Die scheinbaren elektrischen Widerstände sind innerhalb der geothermischen Anomalie mit Werten bis zu 50 Qm äußerst klein, während sie nördlich des geothermischen Feldes auf 100-300 Qm ansteigen, um dann etwa 7 km NW der Anomalie wieder deutlich abzufallen. Selbst in der tieferen Kruste werden keine höheren Widerstände angetroffen. Die integrierte Leitfähigkeit weist das geothermische Feld ebenso als eine Anomalie der elektrischen Leitfähigkeit aus, während nördlich davon die "hochohmige Barriere" bestätigt wurde. Aus den Ergebnissen der Seismik und Magnetotellurik wurde ein Modell für die geothermische Anomalie von Travale und die Toskana abgeleitet, das sich in drei Stockwerke gliedert: - Das unterste Stockwerk, die Übergangszone zwischen Oberem Mantel und Unterkruste in 20-30 km Tiefe ist die Quelle auf steigender heißer Gase und Flüssigkeiten. Die Temperatur beträgt etwa 700° C. - Das mittlere Stockwerk ist von tief reichenden, vertikalen Störungen durchsetzt, die einen konvektiven Wärmetransport durch die hydrothermalen Phasen in das oberste Stockwerk erlauben. Im Gebiet von Travale hat sich durch längs- und zum Era-Graben querstreichende Störungen eine ausgeprägte Schwächezone in der Kruste gebildet, die einen besonders intensiven Wärmetransport zuläßt. Der Temperaturgradient wird mit 15° C/km angenommen. - Das oberste Stockwerk besteht aus Sedimenten und kristallinen Formationen, die im wesentlichen von horizontalen Abscherungs- und Störungsflächen durchzogen sind, in denen hydrothermale Phasen zirkulieren. Innerhalb der Basements hat sich so ein zweites Reservoir ausgebildet, welches das bekannte geothermische Reservoir in den Karbonaten in Tiefen von 1-2 km durch ein ausgeprägtes Bruchsystem speist. Die Temperatur ist in 4 km Tiefe mit 400° C sehr hoch. Die augenblicklich geförderten heißen Gase und Wässer sind meteorologischen Ursprungs und werden an der Oberkante des toskanischen Basements aufgeheizt. Aus tektonischer Sicht besteht das oberste Stockwerk aus allochthonen Decken, die während der Orogenese über die Toskana hinweggeschoben wurden. Dieser tektonischen Kompressionsphase folgte eine Phase starker lateraler Dehnungen, die bis heute andauern. Das System von Grabenbrüchen und tiefgreifenden Verwerfungen ist Ausdruck dieser Dehnungstektonik. Die damit verbundenen Störungszonen tragen zu einer Entwässerung und Entgasung der tiefen Erdkruste bei und lassen die hydrothermalen Phasen in das oberste Stockwerk aufs teigen. In ausgeprägte Schwächezonen, die die gesamte Kruste durchziehen und die durch undurchlässige Schichten nach oben abgeschlossen werden, kann sich so ein geothermisches Reservoir ausbilden.

Description: Tuscany is the strongest geothermal anomaly in continental Europe. Numerous local high enthalpy geothermal fields are to be found within this anomaly, e.g. the Travale field. Electromagnetic soundings have been carried out in this geothermal field, which lies in the Era-Graben, in the years 1980 and 1981. The aim of this study was to find the origin as well as the cause of this partly known anomaly, using the methods of magnetotelluric- and geomagnetic depth soundings to study the distribution of electrical conductivity in the earth's crust downwards to the crust/mantle boundary, at least. Parallel to this study the geothermel anomaly of Travale has been studied with the help of various other methods, including electromagnetic, seismic and geochemical surveys. To localize the geothermal anomaly in the earth's crust was not an easy task. Therefore it seemed to be necessary to develop a model of the anomaly, first, and then to localize it. Earlier electromagnetic investigations (HAAK & SCHWARZ 1981) have shown, that nearly the whole area of Tuscany corresponds to an electrical conductivity anomaly: A well conducting cover, reaching down to 10 km depth is underlain by a high resistive basement. At some places within the geothermal anomaly a zone of high conductivity has been found at the depth of the crust/mantle-boundary (between 20 and 30 km) . Seismic refraction measurements are indicating a wide transition zone between the crust und upper mantle, displayed by alternating high- und extreme low-velocity layers. The time-varying electric- and magnetic fields have been recorded in the Travale area in a broad period range from 6-10.000 s, mainly on two profiles, the one parallel, the other perpendicular to the Era-Graben. The stations have been very close to each other, spacings varied between some hundreds of meters and a few kilometers, to study lateral variations of apparent resistivities within the Graben. In deed, lateral variations of apparent resistivities have been very large in the Travale area. Up to 50-100 s the Era-Graben is the dominating 2D-structure, but for longer periods of investigation the three-dimensionality of the electrical conductivity structure has to be considered. The apparent resistivities inside the geothermal anomaly are extremely low, reaching not more than 50 Gm, even in the lower crust, whereas going up to 100-300 firn north of the geothermal field. Further to NW apparent resistivities are coming down again to 5-5o Gm. Total conductance as well indicates the geothermal field as a local conductivity anomaly, whereas more to the north the poorly conducting "barrier" has been confirmed. Based on the results of the magnetotelluic soundings and those of the seismic survey a geothermal model for the anomaly of Travale as well as for Tuscany has been developed. The crust is built up by 3 stories: - The lowermost story of the transition from the mantle to the crust at 20-30 km depth has to be regarded as the origin of hot gases and fluids. Temperature amounts to 700° C. - The central story is more or less fractured vertically so that pathways allow convective transport of heat by means of hydrothermal fluids to the upper story. In the Travale area a weak crustal zone of faults crossing over has developed, allowing the transport of heat to be very intensive. The temperature gradient is assumed to reach not more than 15° C/km. - The uppermost story consists of sediments and more or less horizontally fractured crystalline formations, filled with hot, circulating fluids. Within the basement a second reservoir has evolved, which feeds the known geothermal reservoir in the carbonate series at 1-2 km depth through fractures and cracks in the top of the basement. The temperature of about 400° C in 4 km depth is extremely high. The actually exploited hot gases and fluids are of meterological origin and heated up at the top of the basement. From the tectonic point of view, the uppermost story consists of allochthonous nappes shifted across Tuscany during orogenesis. This compressive tectonic deformation was followed by strong dilatational forces, which are still active in the whole crust, expressed by the features of graben structures and deep reaching faults. This process gives volatiles and water generated by dehydration in the deep crust the chance to rise to the uppermost story. A basement fractured at the top and an impermeable cover in the uppermost layer will then favour the development of a geothermal reservoir.

Description: thesis

Description: DFG, SUB Göttingen

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉In this contribution we report the first systematic study of zircon U‐Pb geochronology and δ〈sup〉18〈/sup〉O‐〈italic〉ε〈/italic〉Hf〈sub〉(〈italic〉t〈/italic〉)〈/sub〉 isotope geochemistry from 10 islands of the hot‐spot related Galapagos Archipelago. The data extracted from the zircons allow them to be grouped into three types: (a) young zircons (0–∼4 Ma) with 〈italic〉ε〈/italic〉Hf〈sub〉(〈italic〉t〈/italic〉)〈/sub〉 (∼5–13) and δ〈sup〉18〈/sup〉O (∼4–7) isotopic mantle signature with crystallization ages dating the islands, (b) zircons with 〈italic〉ε〈/italic〉Hf〈sub〉(〈italic〉t〈/italic〉)〈/sub〉 (∼5–13) and δ〈sup〉18〈/sup〉O (∼5–7) isotopic mantle signature (∼4–164 Ma) which are interpreted to date the time of plume activity below the islands (∼164 Ma is the minimum time of impingement of the plume below the lithosphere), and (c) very old zircons (∼213–3,000 Ma) with mostly continental (but also juvenile) 〈italic〉ε〈/italic〉Hf〈sub〉(〈italic〉t〈/italic〉)〈/sub〉 (∼−28–8) and δ〈sup〉18〈/sup〉O (∼5–11) isotopic values documenting potential contamination from a number of sources. The first two types with similar isotopic mantle signature define what we call the Galápagos Plume Array (GPA). Given lithospheric plate motion, this result implies that GPA zircon predating the Galápagos lithosphere (i.e., >14–164 Ma) formed and were stored at sublithospheric depths for extended periods of time. In order to explain these observations, we performed 2D and 3D thermo‐mechanical numerical experiments of plume‐lithosphere interaction which show that dynamic plume activity gives rise to complex asthenospheric flow patterns and results in distinct long‐lasting mantle domains beneath a moving lithosphere. This demonstrates that it is physically plausible that old plume‐derived zircons survive at asthenospheric depths below ocean islands.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉Our data define the Galápagos Plume Array defined by mantle 〈italic〉ε〈/italic〉Hf〈sub〉(〈italic〉t〈/italic〉)〈/sub〉 and δ18O values in the range ∼0–164 Ma〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉This finding allows dating back plume activity to, at least, early Middle Jurassic (∼164 Ma)〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Numerical experiments confirm it is plausible that old Plume‐derived zircons survive in the asthenosphere for extended periods of time〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Ministerio de Asuntos Económicos y Transformación Digital, Gobierno de España http://dx.doi.org/10.13039/501100010198

Description: Ministerio de Ciencia e Innovación http://dx.doi.org/10.13039/501100004837

Description: European Research Council http://dx.doi.org/10.13039/501100000781

Description: https://doi.org/10.5281/zenodo.7047729

Description: https://doi.org/10.5281/zenodo.6967187

Description: research

Description: research

Description: research

Description: Es wurden moderne Methoden auf ihre Eignung zur Bestimmung von Fischlarven untersucht. Als Vorbereitung auf die Bestimmung wurden Formen und proportionales Wachstum von Fischlarven der Nordsee und angrenzender Gebiete untersucht. Dazu wurden an 831 Fischlarven aus 33 Arten und 18 Familien die folgenden Messungen durchgeführt: Standardlänge, Präanallänge, Präorbitallänge, Präpektorallänge, Augendurchmesser, Orbitalhöhe, Pektoralhöhe, Analhöhe, Pektoralbreite und Analbreite. Aus den Messungen wurde das Volumen der Larven errechnet. Die Formen von Larven mit einem Volumen zwischen 3 und 5 μl wurden verglichen. Es ergaben sich vier deutlich getrennte Formgruppen: "eel-like", "fusiform", "deep + compressed" und "tadpole-like". Bis auf die Gruppe "fusiform" zeigten alle Gruppen allometrisches Wachstum bei bestimmten Körperproportionen. Die mögliche ökologische Bedeutung dieser Gruppen wird diskutiert. Es wurden drei computergestützte Bestimmungssysteme entwickelt und getestet: Ein numerisches System, ein Expertensystem und eine moderne Datenbank. Als Beispiel einer Methode der numerischen Taxonomie wurde die Quadratische Diskriminanzanalyse untersucht. Dazu wurden aus den durchgeführten Messungen die Diskriminanzfunktionen errechnet und unbekannte Larven zunächst einer Formgruppe und dann einer Art innerhalb der Formgruppe zugeordnet. Die richtige Zuordnung bei dieser Methode betrug 82 % . Die numerische Taxonomie scheint damit zur Bestimmung von Fischlarven grundsätzlich geeignet zu sein. Allerdings ist zweifelhaft, ob genügend Fischlarven (30 - 100 pro Art) zum Aufbau des Systems erhältlich sind. Aufbauend auf dem HALBEISEN-Schlüssel zur Bestimmung von Fischlarven der Nordsee und angrenzender Gebiete wurde das Expertensystem IDEXSYS entwickelt. Es kann als moderne Form traditioneller Bestimmungsschlüssel betrachtet werden. Expertensysteme erweisen sich damit als gut geeignet zur Bestimmung von Fischlarven. Mit einem modernen Datenbankprogramm wurde ein Such- und Eingabeformular mit etwa 80 Merkmalen entwickelt. Alle in der Nordsee und den angrenzenden Gebieten vorkommenden 126 Fischlarvenarten wurden auf diese Merkmale überprüft und in die Datenbank eingegeben. Der Test des Systems ergab, daß durchschnittlich nur drei Merkmale zur Bestimmung einer Fischlarve erforderlich waren. Bei einem Vergleich der Methoden wird für die Bestimmung von Fischlarven dem Datenbanksystem der Vorzug gegeben.

Description: Highlights • Development of an autonomous DIC analyzer based on Conductometric technique using a cell with 4 hollow brass electrodes. • CO2 extraction from seawater using a gas diffusion cell with a “Tube In A Tube” configuration and a gas permeable membrane. • Formulation of mathematical temperature and salinity correction to determine accurate DIC concentration. • Demonstration of the analyzer performance in the southwest Baltic Sea. Abstract Background The increase in anthropogenic CO2 concentrations in the Earth's atmosphere since the industrial revolution has resulted in an increased uptake of CO2 by the oceans, leading to ocean acidification. Dissolved Inorganic Carbon (DIC) is one of the key variables to characterize the seawater carbonate system. High quality DIC observations at a high spatial-temporal resolution is required to improve our understanding of the marine carbonate system. To meet the requirements, autonomous DIC analyzers are needed which offer a high sampling frequency, are cost-effective and have a low reagent and power consumption. Results We present the development and validation of a novel analyzer for autonomous measurements of DIC in seawater using conductometric detection. The analyzer employs a gas diffusion sequential injection approach in a “Tube In A Tube” configuration that facilitates diffusion of gaseous CO2 from an acidified sample through a gas permeable membrane into a stream of an alkaline solution. The change in conductivity in the alkaline medium is proportional to the DIC concentration of the sample and is measured using a detection cell constructed of 4 hollow brass electrodes. Physical and chemical optimizations of the analyzer yielded a sampling frequency of 4 samples h−1 using sub mL reagent volumes for each measurement. Temperature and salinity effects on DIC measurements were mathematically corrected to increase accuracy. Analytical precision of ±4.9 μmol kg−1 and ±9.7 μmol kg−1 were achieved from measurements of a DIC reference material in the laboratory and during a field deployment in the southwest Baltic Sea, respectively. Significance This study describes a simple, cost-effective, autonomous, on-site benchtop DIC analyzer capable of measuring DIC in seawater at a high temporal resolution as a step towards an underwater DIC sensor. The analyzer is able to measure a wide range of DIC concentrations in both fresh and marine waters. The achieved accuracy and precision offer an excellent opportunity to employ the analyzer for ocean acidification studies and CO2 leakage detection in the context of Carbon Capture and Storage operations.

Description: Zentrale Aushandlungs- und Gestaltungsprozesse in der Energiewende finden vor Ort in den Regionen und Kommunen statt. Wie gelingt es hier, die Transformation demokratisch zu gestalten und das politische Versprechen von Teilhabe und Mitgestaltung einzulösen? Dieser Frage widmet sich die vorliegende Studie. Um herauszufinden, welche Erfolgsfaktoren und Herausforderungen in Ansätzen der finanziellen Beteiligung sowie in dialogischen und konfliktsensiblen Formaten liegen, haben wir drei unterschiedliche Fallbeispiele zu materieller und immaterieller Beteiligung in der Energiewende analysiert. Auf dieser Grundlage benennt die Studie fünf konkrete Handlungsempfehlungen zur Stärkung von kommunalen Transformationskapazitäten für Bund und Länder.

Description: Fennoskandien ist seit jeher ein Gebiet, auf das sich die geowissenschaftlichen Interessen konzentrierten. Ein Grund dafür ist die seit langem bekannte Landhebung von ca. 10 mm pro Jahr im Zentrum, das im nördlichen Teil des Bottnischen Meerbusens liegt. Neben den seismischen Untersuchungen der Struktur der Lithosphäre wird seit 1966 mit Hilfe der Präzisionsgravimetrie entlang der sog. Landhebungslinien versucht, durch wiederholte Schweremessungen den Effekt der Landhebung zu erfassen und dadurch, neben den Präzisionsnivellements, auch Hinweise auf den Mechanismus zu erhalten. Parallel dazu wurden an vielen Orten gravimetrische Gezeitenbeobachtungen durchgeführt, um realistische Gezeitenparameter für die Korrektur der Präzisionsgravimetrie zu ermitteln. Dabei stellte sich heraus, daß im Bereich der norwegischen Küste eine starke Anomalie der Parameter von bis zu 35% in der Amplitude und mehr als 20° in der Phase festzustellen ist, die man auf die Wirkung der ozeanischen Auf lastgezeiten zurückführen kann. Die vorliegende Arbeit befaßt sich mit den gravimetrischen Gezeitenregistrierungen entlang der Geotraverse "Blaue Straße". Dieses Profil beginnt an der norwegischen Küste in der Nähe des Polarkreises und läuft mit etwa 125° in südöstlicher Richtung bis an den Finnischen Meerbusen nahe der sowjetischen Grenze. Die Besonderheit der Stationsauswahl liegt in der Verdichtung der Meßorte im Bereich der Küste: Hierdurch ist es möglich, das Abklingen des Effektes der ozeanischen Auflast zu erfassen. Dies erlaubt gezielte Mode 11 Untersuchungen zur Überprüfung von lokalen Meeresgezeitenmodellen mit einer unabhängigen Methode: Neben den elastischen Eigenschaften der Lithosphäre, insbesondere der Tiefe der Krusten-/Mantelgrenze gehen lediglich die Verteilung der Amplituden und Phasen der Meeresgezeit in die Rechnung ein, nicht aber die Parameter und die Randbedingungen, die zu ihrer Modellierung benötigt werden. Durch die Verdichtung der Stationen im Küstenbereich können auch Aufschlüsse über die Struktur der Lithosphäre, vor allem die Moho - Tiefe, gewonnen werden. Es standen für die Messungen in den Jahren 1980 bis 1983 fünf Gravimeter zur Verfügung, mit denen insgesamt sieben Stationen vermessen wurden. Die Registrierzeiträume lagen zwischen 10 und 26 Monaten. Im Folgenden werden die bisherigen geowissenschaftlichen Befunde für Fennoskandien und für das Pof il "Blaue Staße" im Besonderen zusammengefaßt, die Methoden der Auflastberechnung diskutiert und die Problematik der Modellierung der Meeresgezeiten dargestellt. Die Messungen schließen intensive experimentelle Arbeiten wie auch Überlegungen zur Datenbearbeitung und Analyse ein. Besonderer Wert war dabei auf die Kalibrierung der Gravimeter zu legen, die im Berliner Gezeitenobservatorium (Insulaner) erfolgte. Die Interpretation der Residuen der Welle M2 hinsichtlich der Auf lastgezeiten ergab schließlich, daß die Schelfgezeiten bei der Modellierung in der Phase um 15 bis 20° verzögert werden müßten, um der Beobachtung zu entsprechen. Hierdurch wird natürlich das Meeresgezeitenmodell nicht korrigiert, die gefundenen Abweichungen sind aber ein Hinweis für die Berechnung der Modelle. Überdies ergab sich eine besonders gute Übereinstimmung für eine flache Kruste. Dies steht im Einklang mit seismischen Ergebnissen aus dem Küstenbereich und bestätigt das Fehlen einer Gebirgswurzel unter den Kaledoniden. Auch für das Residuum der Welle 01 wird eine Inkonsistenz mit dem Meeresgezeitenmodell festgestellt, die sich hier allerdings nicht aus der Modellierung der Schelfgezeiten erklären läßt: Die Amplituden von 01 liegen bei 3 bis 5 cm. Die lokale Wirkung ist demnach gegenüber M2 (80 bis 100 cm) zu klein. Für die Korrekturen der Präzisionsschweremessungen komplettiert dieses Profil das bereits vorhandene Stationsnetz und ermöglicht die flächenhafe Interpolation. Daraus lassen sich dann später unter Hinzuziehung der anderen Hauptwellen realistische Gezeitenkorrekturen für alle Stationen ermitteln.

Description: Fennoscandia has always been an area of special interest for geoscientists. One reason for that ist certainly the well known land uplift of about 10mm/yr in its center, which is located in the northern part of the Gulf of Bothnia. Besides the seismic research of the structure of the Lithosphere since 1966 precise gravity surveys are carried out along the so called land uplift lines. By repetition of these measurements it is hoped to monitor the effect of land uplift, and to get indications of its mechanism. In addition tidal gravity observations were carried out at many places to achieve realistic tidal parameters for the correction of the precise gravity surveys. It was found that esp. adjacent to the sea there is a strong anomaly of the parameters of up to 35% in amplitude and more than 20° in phase. This can be allocated to the effect of the ocean tides. The present work deals with the tidal gravity measurements along the geotraverse 'Blue Road'. This profile starts at the Norwegian coast close to the polar circle running about 125° south-east till the Gulf of Finland, close to the Sowjet border. The speciality of the choice of the station locations is in their concentration near the coast. By these means it is possible to monitor the decrease of the effect of the ocean loading. This enables the check of local ocean tide models by an independent method: In addition to the elastic properties of the Lithosphere, esp. the depth of the crust/mantle boundary, only the distribution of the calculated ocean tidal amplitudes and phases are included into the calculations; the parameters and boundary conditions necessary for the calculation of these models are not used. By concentration of the stations near the coast also hints on the structure of the Lithosphere, esp. the depth of the Moho can be achieved. The measurements were carried out during a period from 1980 to 1983, and five gravimeters were available to measure at seven stations. The recording intervals were between 10 and 23 months each. In the following the geoscientif ic findings obtained up to now for Fennoscandia are put together, in detail for the 'Blue Road' profile. The methods of loading calculations and the problem of modelling the ocean tides are reviewed. The preparations of the measurements include intense experimental work as well as efforts in data treatment and analysis. Special care was necessary for the calibration of the gravimeters which was performed at the Tidal Observatory Berlin (Insulaner). The interpretation of the tidal residuals of the constituent M2 resulted in the fact, that the shelf tides should be retarded by 15 to 20° to fit the observations. Of course, this is no way to correct the tidal chart, but it provides boundary conditions for the calculation of these models. In addition, the best fit was achieved assuming a fairly thin crust in the coastal area. This corresponds to seismic results and confirms the lack of a mountain root below the Caledonides. For the residual of 01 the interpretation showed a significant restvector, too. But here it is not possible to use the shelf area for an explanation: In contrary to M2 (amplitudes of up to 100 cm) the 01 amplitudes of the shelf tides are only in the order of 3 to 5 cm, which is too small. These profile measurements complete the Fennoscandian net of tidal results. This enables the spatial interpolation of the values and, by addition of the other main tidal constituents, it will be possible to derive realistic tidal corections for the repeated precise gravity surveys.

Description: thesis

Description: DFG, SUB Göttingen

Description: In a regional study based upon a large set of sea-level data and meteorological data, the long-period variations in sea-level and the fluctuations of meteorological parameters have been investigated for the Norwegian coast. In the period range between 1 and 20 years, the sea-level is found to be dominated by a few distinct signals. The interaction between meteorological parameters and sea-level is discussed. The sea-level is found to respond to long-period air pressure variations as an inverse barometer. Most of the sea-level signals with periods between 1 and 5 years are at least partly due to similar signals in air pressure and/or wind stress. In the Chandler band, the meteorological parameters contain at least two distinct signals. The oceanic pole tide signal is masked by the atmospheric forcing of the sea-level. This leads to temporal variations in the apparent pole tide, which are uncorrelated with the temporal variations of the Chandler wobble. The air pressure corrected pole tide is still not an equilibrium tide, but the large deviations in phase from equilibrium may well be due to unaccounted effects of wind stress and temperature. The Chandler wobble in polar motion is important as the driving force of the pole tide. In an extensive numerical investigation, the simple and physically reasonable model of a single frequency, damped, harmonic oscillation, which is frequently excited at random times and with random amplitude is found to explain all features of the observed Chandler and annual wobbles. Comparing the results from the numerical investigations to the results from analyses of the polar motion gives strong evidence for the Chandler wobble period to be either 428.5± 1.0 days or 437.2±0.8 days and not the usually assumed period of ≈434 days. No final decision can be made which of the two periods is the true Chandler period, though the shorter one is favoured by several facts. The signals in meteorological parameters can all be related to the variations in sunspot numbers. A non-linear response of the atmosphere to the annual solar forcing, which is modulated by the sunspot cycles explains the observed frequency patterns. The excess of the observed sunspot effects in surface air temperature over those predicted from simple climate models by a factor of 10 indicates the existence of strong positive feedback mechanisms, which are responsible for the signals in air pressure and wind stress, too. The 18.6-year nodal tide lags the equilibrium tide by 0.8 radian, while the amplitudes exceed the equilibrium amplitudes by a factor of 3 to 5. At most parts of the coast, the nodal modulation of the amplitude of the fortnightly lunar tide Mf also lags the equilibrium modulation by 0.5 to 0.7 radian. The amplitude of the nodal modulation is close to equilibrium, except for Oslo and Bergen. At the latter stations, resonance effects may modify the modulation. Mf itself is found to have an amplitude of two to three times the equilibrium amplitude and a phase lag of slightly more than π. Determining the land uplift at the Norwegian coast from the trend in sea-level leads to a varying pattern of isolines, with the land uplift gradient being perpendicular to the general direction of the coast line, and being rather large at parts of the coast. At most parts of the coast, the zero line is further out in the sea than given on other published charts.

Description: Die vorliegende Arbeit über langperiodische Variationen des Meeresspiegels entlang der norwegischen Küste basiert auf umfangreichen Datensätzen von Meeresgezeiten und Meteorologie. Alle verwendeten Meeresgezeitendaten lagen als Stundenstützstellen vor, die nach sorgfältiger Fehlersuche auf monatliche Mittelwerte reduziert wurden. Die längsten Meeresgezeiten-Registrierungen an der norwegischen Küste sind für Oslo und Bergen verfügbar, wo die Zeitreihen das Intervall von 1914 bis 1985 umfassen. Für sieben Stationen lagen Registrierungen von 1952 bis 1985 vor, und für jeweils weitere 2 Stationen waren Registrierung für die Zeiträume von 1961 bis 1985 bzw. von 1970 bis 1985 verfügbar. Die meteorologischen Daten standen an drei Station für die längeren Zeiträume von 1952 bis 1983 (Oslo und Bergen) bzw. von 1957 bis 1975 (Narvik ) zur Verfügung, und für 15 Stationen waren die Daten für den kürzeren Zeitraum von 1970 bis 1984 vorhanden. Dabei ist der Luftdruck mit einem Stützstellenabstand von drei Stunden registriert worden, während die übrigen Parameter (Windgeschwindigkeit und -richtung, Lufttemperatur) mit einem Stützstellenabstand von 6 Stunden vorliegen. Auch hier wurden aus den Daten monatliche Mittelwerte berechnet. Da die Wirkung des Windes auf die Meeresoberfläche als dem tangentialen Windstress proportional angenommen wird, wurden aus den Winddaten monatliche Mittelwerte für die beiden tangentialen Windstress-Komponenten berechnet. In dem Periodenbereich von einem bis etwa zwanzig Jahren sind die Schwankungen des Meeresspiegels von einigen wenigen, fast-periodischen Variationen bestimmt. Die Perioden, die in den Meeresspiegelschwankungen gefunden wurden, sind überwiegend auch in den untersuchten meteorologischen Parametern zu finden. Dabei sind diese Signale in Periode, Amplitude und Phase räumlich sehr homogen. Bei der Untersuchung der Signale in den meteorologischen Parametern Luftdruck, Ost-West- und Nord-Süd- Komponente des Windstress und Lufttemperatur zeigte sich, daß der überwiegende Teil der Perioden in ein Muster paßt, daß sich aus der Modulation der jährlichen solaren Anregung der Atmosphäre durch den Sonnenfleckenzyklus ergibt. Aus der Literatur ist bekannt, daß die Variationen in den Sonnenflecken mit Schwankungen in der Solarkonstanten und damit mit Variationen im Wärme-Input in das System Atmosphäre-Ozean verbunden sind. Die in der Lufttemperatur gefundenen Schwankungen mit Perioden zwischen einem und zwanzig Jahren haben Amplituden von ≈0.5°C und liegen damit um eine Größenordnung höhere als die aus einfachen Klima-Modellen abgeschätzten Effekte des Sonnenfleckenzyklus. Nur wenn man die Existenz positiver Rückkopplungs- Mechanismen annimmt, können die in den Beobachtungen gefundenen Variationen erklärt werden. Diese Rückkopplungen sind in beobachteten Veränderungen der vorherrschenden Wetterbedingungen mit dem Sonnenfleckenzyklus zu suchen. Änderun- gen der vorherrschenden Wetterbedingungen erklären dann auch das Vorhandensein dieser Perioden in Luftdruck und Windstress. Benutzt man die monatlichen Mittelwerte um die Antwort des Meeresspiegels auf Luftdruckschwankungen zu ermitteln, so ergibt sich für den größten Teil der Küste eine isostatische Antwort, vergleichbar einem inversen Barometer. Abweichungen finden sich insbesondere an Stationen am Ende von Fjorden (Oslofjord, Ofotfjord). Dort ist dann aber die Korrelation zwischen Windstress und Meeresspiegel höher als an Stationen an der offenen Küste, so daß diese Abweichungen von der isostatischen Antwort in wesentlichen durch Windeffekte bewirkt werden. Im Bereich der Chandler Periode sind im Luftdruck mindestens zwei Signale vorhanden, die mit Perioden von ≈1.14 Jahren und ≈1.22 Jahren die vom Chandler Wobble bewirkte Poltide verdecken. Die Signale im Luftdruck haben Amplituden (bis zu 200 Pa), die bei einer isostatischen Antwort des Meeresspiegels (etwa -1 cm/HPa) zu Signalen im Meeresspiegel führen, deren Amplituden deutlich über der Amplitude einer Gleichgewichts-Poltide (etwa 0.5 cm an der norwegischen Küste) liegen. Zu diesen Signalen im Luftdruck kommen noch Signale im Windstress und in der Lufttemperatur hinzu. Die Veränderungen in der Lufttemperatur können mit einiger Phasenverschiebung zu Signalen in der Wassertemperatur und über den Dichteeffekt zu entsprechenden Signalen im Meeresspiegel führen. Signale in der Temperatur des Meerwassers im Chandler-Band sind aus der Literatur bekannt. Diese komplizierte Wechselwirkung zwischen Atmosphäre und Ozean führt zu einer Verdeckung der vom Chandler Wobble bewirkten Poltide. Die Frequenz-Unterschiede zwischen den Signalen im Chandler-Band in der Atmosphäre und der Chandler Periode selbst (die auch der Periode der Poltide entspricht), führen zu langperiodischen Modulationen einer scheinbaren Poltide. Dadurch sind die beobachteten zeitlichen Variationen der Poltide nicht korreliert mit den zeitlichen Variation des Chandler Wobbles. Wird der isostatische Effekt des Luftdrucks auf den Meeresspiegel eliminiert, so ergibt sich eine Poltide, deren Amplitude nahe der Gleichgewichtsamplitude liegt. Der wesentliche Teil der Amplituden-Überhöhung der beobachteten Poltide gegenüber der Gleichgewichtsamplitude ist damit auf Luftdruckeffekte zurückzuführen. Die Phasenbeziehung zwischen beobachteter Poltide und der Gleichgewichtstide zeigt allerdings starke zeitliche Variationen. So ist im Interval von 1970 bis 1979 die Phase der beobachtete Poltide nahe der Gleichgewichtstide, während sich für das Interval von 1957 bis 1979 deutliche Abweichungen ergeben. Diese zeitliche Variabilität ist durch das Zusammenwirken verschiedener Signale im Chandler Band zu erklären. Insbesondere die in der Temperatur und im Wind gefundenen Signale mit Perioden nahe bei 14 Monaten können diese Variationen bewirken. Insgesamt wurden keine Hinweise gefunden auf eine von der Gleichgewichtstide abweichende Poltide. Der Chandler Wobble in der Polbewegung ist als Ursache für die Poltide wichtig für die vorliegende Arbeit. Da die in der Literatur publizierten Resultate bezüglich des Chandler Wobbles sehr widersprüchlich sind, wurden die Polbewegungsdaten des ILS/IPMS und vom BIH im Rahmen dieser Arbeit erneut analysiert. Mit Hilfe umfangreicher numerischer Untersuchungen konnte gezeigt werden, daß das einfache und physikalisch sinnvolle Modell eines mono-frequenten Chandler Wobbles, der häufig an zufälligen Zeitpunkten mit zufälliger Amplitude angeregt wird, ausreicht, um alle Eigenschaften des beobachteten Chandler Wobbles zu erklären. Durch Vergleich der Modellrechungen mit den Ergebnissen aus der beobachteten Polbewegung ergab sich, daß die tatsächliche Chandler Periode entweder bei 428.5± 1.0 Tagen oder bei 437.2±0.8 Tagen liegt, und nicht bei den üblicherweise angenommenen ≈434 Tagen. Dieses überraschende Ergebnis ist von großer Bedeutung für alle Arbeiten zur rheologischen Struktur der Erde. Dabei ist anzumerken, daß noch keine endgültige Aussage möglich ist, welche der beiden Perioden der tatsächlichen Chandler Periode entspricht. Allerdings wird die Periode von 428.5 Tagen durch einige Ergebnisse bevorzugt. Die in der Literatur üblicherweise genannte Periode von 434 Tagen ergibt sich gewöhnlich aus stark geglätteten Spektren. Diese Glättung führt bei einer Anregung nach dem oben beschriebenen Modell zu fehlerhaften Perioden. Die Untersuchung der aus den Polbewegungen ermittelten Gleichgewichtsbewegungen des Meeresspiegels erbrachte eine weitere interessante Korrelation: Eliminiert man aus diesen Gleichgewichtsbewegungen Poltide und jährliche Variation, so findet sich in den Residuen eine quasi-periodische Schwankung mit einer Periode von grob 30 Jahren. Diese Variation in den Gleichgewichtsbewegungen ist auf die als Markowitz Wobble bezeichnete Polbewegung zurückzuführen. Eine entsprechende, phasengleiche Variation findet sich auch in den Residuen der Meeresspiegelschwankungen, wenn man alle wichtigen Signale mit Perioden von einschließlich einem Jahr bis hin zu etwa 10 Jahren eliminiert. Falls diese Korrelation nicht zufällig ist, so müßte sie auch global zu finden sein. In der globalen Oberflächentemperatur und in der Änderung der Tageslänge finden sich ebenfalls Variationen, die mit den im residualen Meeresspiegel und in den Gleichgewichtsbewegungen gefundenen Signalen korrelieren, wobei die Variationen in der globalen Temperatur gegenüber den andern Parametern phasenverschoben sind. Die nodale Tide mit einer Periode von 18.6 Jahren zeigt entlang der norwegischen Küste gegenüber der Gleichgewichtstide eine Phasenverschiebung von etwa 0.8 Radian, und die Amplituden liegen um einen Faktor von 3 bis 5 über der entsprechenden Gleichgewichtsamplitude. Die Untersuchung der Variationen der Amplitude der vierzehntägigen Tide Mf zeigt eine ähnlich große Phasenverschiebung zwischen der beobachteten und der erwarteten nodalen Modulation, wobei hier die relativen Amplituden für alle Stationen mit Ausnahme von Oslo und Bergen nahe den Erwartungen liegen. Allerdings ist hier zu bemerken, daß die Amplituden der Mf um den Faktor 2 bis 3 über der Gleichgewichtstide liegen, und somit auch die Modulationen entsprechend erhöht sind. Die Unterschiede in Oslo und Bergen deuten auf Resonanz-Effekte hin. Der Trend im Meeresspiegel relativ zum Land ist an der norwegischen Küste im wesentlichen auf die Landhebung infolge der post-glazialen Entlastungsbewegungen zurückzuführen. Bestimmt man die Isolinien der Landhebungen aus den in dieser Arbeit ermittelten Trends, so ergeben sich Linien, die zu dem generellen Verlauf der Küste parallel sind. Bei Ålesund ergibt sich eine deutliche Verzerrung dieser Linien. In Ålesund finden sich starke zeitliche Variationen im Trend, die mit kleinräumigen Prozessen in Verbindung stehen müssen. Generell ist der Gradient der Landhebung senkrecht zum großräumigen Verlauf der Küste. Der hier ermittelte Gradient ist aber höher als in bisher publizierten Arbeiten, und die Lage der Nullinie ist weiter zur See hin verschoben.

Description: thesis

Description: DFG, SUB Göttingen

Description: Vessel-mounted Acoustic Doppler Current Profilers (ADCPs) provide velocity profiles of the upper ocean along the ship track. They are a key tool in oceanographic research to study the oceanic circulation and the associated distribution of mass, heat, contaminants and other tracers. In order to obtain high-quality ocean current data from vessel-mounted ADCP measurements, a number of requirements must be met, from system installation and data acquisition measures to certain essential processing steps. Here, we present an open-source Python toolbox called OSADCP for scientists to convert, clean, calibrate and organize binary raw vessel-mounted ADCP data for scientific use. The toolbox is designed to process ADCP measurements in deep water by Teledyne RDI Ocean Surveyor ADCPs and the data acquisition software VMDAS.

Description: Der Biodiversitätsverlust schreitet in bedrohlichem Ausmaß voran. Mit dem Global Biodiversity Framework und voraussichtlich dem Nature Restoration Law bestehen nun auf internationaler und europäischer Ebene vielversprechende Ansätze, ihm Herr zu werden. Jetzt ist der Bundesgesetzgeber – nicht zuletzt aus verfassungsrechtlichen Erwägungen – aufgerufen, daran anzuknüpfen. Dazu bietet sich die Regelungsform eines Rahmen- und Politikplanungsgesetzes an, wie sie schon aus dem Klimaschutzgesetz und dem Klimaanpassungsgesetz bekannt ist. Der Aufsatz beleuchtet den internationalen, europa- und verfassungsrechtlichen Hintergrund eines solchen ‘Biodiversitätsschutzgesetzes’ und diskutiert – unter Zusammenarbeit sowohl rechts- als auch naturwissenschaftlicher Autor:innen – formale und materielle Ausgestaltungsmöglichkeiten.

Description: The expedition AL570 with the RV Alkor was carried out within the framework of the interdisciplinary DAM MGF-OSTSEE Project “Potential effects of closure for bottom fishing in the marine protected areas (MPAs) of the western Baltic Sea – baseline observations” funded by the Ministry of Education and Research (BMBF). Within MGF-OSTSEE a consortium of scientists from various institutions investigates how benthic ecosystems in Natura 2000 areas within the German exclusive economic zone develop after the exclusion of bottom trawling. Major goals of the project are i. the initial assessment of the environmental state and its variability in- and outside the three Natura 2000 areas Fehmarnbelt, Oder- and Rönnebank under the ongoing pressure of bottom trawling and ii. the general assessment of the effect of bottom trawling on benthic communities and benthic biogeochemical functioning as well as their development after fishery exclusion. The cruise AL570 concludes a series of three previous expeditions EMB238 (2020) and EMB267/268 (2021) and aimed to survey all components of the benthic food web including prokaryotes, protozoans, meiofauna and macrofauna, as well as sediment properties and biogeochemical processes in selected working areas in- and outside of the MPA. The working program comprised 156 station activities of various gears for biological and biogeochemical sampling of sediments. Solute exchange between the sediment and the water column was investigated using Landers and a novel underwater vehicle the Deep-Sea Rover (DSR) Panta Rhei. Investigations in the water column, seafloor observation and deployments of a dredge supplemented the station work. Due to stormy weather in situ solute fluxe measurements were not performed at the Rönnebank.

Description: In this deliverable, we perform Earth system model (ESM) simulations to assess the role of land-based and ocean-based negative emission technologies (NETs) for achieving the temperature target set by the 2015 Paris Agreement. The dataset provided from this work package will be used for investigating carbon sequestration potential, side-effects and potential constraints of combining oceanic and terrestrial NETs with the help of an earth system model, NorESM2. Two long NorESM2 coupled simulations with SSP5-3.4-OS scenario are conducted to check the CDR potential of terrestrial CDR, and terrestrial and marine CDR together by combining land-based Bioenergy for Carbon Capture and Storage (BECCS) and Ocean Alkalinization Enhancement (OAE) scenarios together. For the terrestrial BECCS simulation, the default land use distribution in the original CMIP6 SSP5-3.4 land use dataset is modified to accommodate more bioenergy crop in the future while keeping the total crop area of 2015 for food throughout the century and combining it with a bio-CCS system. For the second simulation we combined the above terrestrial BECCS simulation with 2030-high OAE scenario from Deliverable 4.6. A higher amount of carbon captured by making use of the carbon sequestration potential of land and ocean together.

Description: thesis

Description: DFG, SUB Göttingen

Description: Im nördlichen Bereich der Provinz Kantabrien (Nordspanien) wurden Sedimente der "Mittelkreide" (Oberalb und Cenoman) unter stratigraphischen, faziellen und sedimentologi sehen Gesichtspunkten bearbeitet. Strukturell gehört die Region zum Nordkantabrischen Becken (NCB), dessen Einsenkung mit tektonischen Bewegungen im mittleren Valangin beginnt. Das NCB ist eines der zahlreichen Sedimentbecken, die sich infolge des mesozoischen Riftings und Spreadings in der Biscaya auf dem iberischen Nordschelf bilden. Strukturgeologisch zeigt das NCB eine E/W-Ausrichtung zwischen zwei Hochgebieten im S und N (Cabuemiga-Rücken und Liencres-Hoch), die als "Santillana-Achse" bezeichnet wird. Im W grenzt das NCB an das Paläozoikum des Asturischen Massivs. Östlich Santander wird es strukturell und faziell durch die N/S-streichende Rio-Miera-Flexur vom hochsubs identen Basko-Kantabrischen Becken abgetrennt. Die Sedimentation im NCB wird stark von tektonischen Ereignissen im sich bildenden Biscaya-Ozeans beeinflußt, durch welche die Strukturierung der Schichtenfolge in sedimentäre Megasequenzen erfolgt. Im Alb und Cenoman können folgende Megasequenz-Grenzen erkannt werden, durch welche die Megasequenzen des Alb und Cenoman definiert werden: • Santander-Tectoevent (Cenoman/Turon-Grenzbereich) • Vraconian Tectoevent (hohes Oberalb) • "Mittelalb-Ereignis" ("break-up unconformity", [?hohes] Unteralb). Das Mittelalb-Ereignis fuhrt im Arbeitsgebiet zum Zerbrechen der faziell wenig differenzierten Urgon-Karbonatplattformen des Clansay (Oberapt/Unteralb) in ostvergente Kippschollen. In den entstehenden N/S-orientierten Halbgräben werden im Mittelaib fluvio-deltaische Klastika abgelagert, während auf den Hochschollen eine Verkarstung erfolgt. Im tiefen Oberalb initiiert ein transgressiver Puls die weit verbreitete Ablagerung mariner Sedimente im NCB. Dieses transgressive Ereignis ist in ganz Iberien nachzuweisen. Im Laufe des Oberalb kommt es zu einem Onlap mariner Sedimente auch auf den ehemals emergenten Hochschollen und zu einem Ausgleich des durch das Mittelalb-Ereignis erzeugten Paläoreliefs. Durch weit verbreitete Emersion des NCB's infolge tektonischer Bewegungen im oberen Oberalb (Vraconian Tectoevent) wird die sedimentäre Megasequenz des Alb beendet. Die sedimentäre Megasequenz des Cenoman beginnt im Alb/Cenoman-Grenzbereich mit der Progradation deltaischer Klastika. Die im NCB der Santillana-Achse folgend von W nach E kanalisiert werden. Dieses "Santillana-Delta" mündet im Bereich Galizano/Langre östlich Santander in das Basko-Kantabrische Becken und verzahnt sich dort mit den Prodelta-Sedimenten des Valmaseda-Deltas ("Schwarzer Flysch" der Bilbao-Region). Die differentielle Subsidenz im NCB in Folge des Vraconian Tectoevents wird von den Delta-Sedimenten ausgeglichen. Im tiefen Untercenoman (untere Mantelliceras mantelli-Zone) gestaltet eine bedeutende transgressive Faziesentwicklung das gesamte NCB in einen vollmarinen, karbonatisch dominierten Ablagerungsraum um. Dieser transgressive Puls dürfte mit der "Untercenoman-Transgression" sensu lato korrelieren. Im Cenoman können folgende Ammoniten-Biozonen erkannt werden: • Obercenoman: Eucalycoceras pentagonum-Zone, und Metoicoceras geslinianum-Zone [pars] • Mittel cenoman: [Cunningtoniceras inerme-Zone], Acanthoceras rhotomagense-Zone und A. jukesbrownei-Zone • Untercenoman: Mantelliceras mantelli-Zone und M. dixoni-Zone. Das höchste Obercenoman (oberer Teil der geslinianum-Zone und die Neocardioceras juddii-Zone) fehlt im NCB. In der oberen mantelli-Zonc des NCB etabliert sich in weiten Bereichen die flachmarine Karbonat-Fazies der Altamira-Plattform, die sich östlich der Rio-Miera-Flexur mit mächtigen Beckensedimenten (Mergel, Knollenkalke, Kalk/Mergel-Rhythmite) verzahnt. Im Mittel- bis unteren Obercenoman wird die Altamira-Plattform in drei Schritten von E nach W "ertränkt". Die prominenten Drowning-Unconformities (mineralisierte Hartgründe mit Ammoniten) werden dabei stufenweise nach W jünger. Im Obercenoman (pentagonum-Zono) ist die gesamte Altamira-Plattform ertränkt und weite Teile des NCB werden in die Beckensedimentation einbezogen. Die Ablagerungsgeschichte des Cenoman wird durch das Santander-Tectoevent in der oberen geslinianum-Zonc beendet, infolgedessen weite Teile des NCB trockenfallen. Selbst in hochsubsidenten Beckenprofilen ist der Cenoman/Turon-Grenzbereich durch eine Schicht lücke gekennzeichnet. Die fazielle Entwicklung der cenomanen Megasequenz ist durch die schubweise voranschreitende ("pulsierende") Cenoman-Transgression geprägt. Insgesamt können im Cenoman sechs Sequenzgrenzen (SB's) erkannt werden, durch die die Ablagerungssequenzen DS Ce I bis VI definiert werden. Ihre stratigraphischen Positionen sind: • SB Ce VI = obere geslinianum-Zonc • SB Ce V = Wende Mittel/Obercenoman • SB Ce IV = basale jukesbrownei-Zone • SB Ce III = hohe dixoni-Zone • SB Ce II = obere mantelli-Zone • SB Ce I = untere mantelli-Zone. Im regionalen Vergleich zeigt sich für das Cenoman eine gute Übereinstimmung mit sequentiellen Gliederungen aus dem Basko-Kantabrischen Raum. Überregionale Vergleiche dokumentieren, daß viele der Meeresspiegel-Bewegungen im Cenoman (z.B. SB Ce III, mfz in der rhotomagense-Zone, SB Ce IV, HST in der pentagonum-Zone) über weite Entfernungen korreliert werden können und wahrscheinlich eustatische Signale darstellen. Die Korrelation mit der "globalen Meeresspiegel-Kurve" (Exxon Chart) ist schlecht. Betrachtet man die im Cenoman im NCB abgelagerten Sedimente als "2nd-order cycle", so zeigt sich ein übergeordneter transgressiver Trend mit einem maximalen Onlap im Obercenoman innerhalb der mfz von DS Ce VI (pentagonum-Zone). Das NCB zeigt im Oberalb und Cenoman im biogeographischen Vergleich starke tethyale Einflüsse. Das Turrilites scheuchzerianus/Neohibolites ultimus-Evert. im tiefen Mittelcenoman des NCB korreliert in bio-, sequenz- und Isotopen-stratigraphischer Hinsicht mit dem Actinocamax primus-Event NW-Europas, womit eine eventstratigraphische Anbindung an das "temperierte" Cenoman erreicht werden kann.

Description: Mid-Cretaceous (Upper Albian and Cenomanian) sediments in the northern part of the province of Cantabria (northern Spain) were investigated with the emphasis on stratigraphical and sedimentological aspects. Structurally, the area belongs to the North Cantabrian Basin (NCB), the depositional history of which started with distensional tectonic movements in the Mid-Valanginian. The NCB is one of the numerous sedimentary basins which developed on the north Iberian continental margin in consequence of the rifting and spreading in the Bay of Biscay during Mesozoic times. It is a gulf-like basin with an E/W-elongation ("Santillana axis"). In the south and in the north the NCB is bordered by the Cabuemiga Ridge and the Liencres High, respectively. To the west, the NCB is bordered by the Palaeozoic Asturian Massif; in the east, the N/S-trending Rio Miera Flexure forms a structural boundary to the strongly subsiding Basco-Cantabrian Basin. The depositional history of the NCB was strongly influenced by tectonic events which can be related to the evolving Biscay Ocean. These tectoevents give rise to a gross subdivison of the succession into sedimentary megasequences. Three tectonically induced megasequence boundaries can be recognized in the Albian and Cenomanian, defining the Albian and Cenomanian megasequences: • Santander-Tectoevent (Cenomanian/Turonian boundary interval) • Vraconian Tectoevent (late Late Albian) • "Middle Albian event" (break-up unconformity, [?late] Early Albian). The "Middle Albian event" caused a disintegration of the widespread Urgonian Clansay platforms (Late Aptian/Early Albian) into a palaeo-relief of eastward-dipping tilted blocks. In the N/S trending halfgrabens, fluvio-deltaic clastics were deposited during the Middle Albian, whereas the exposed tilted block crests were karstified. A strong transgressive pulse flooded the NCB in the early part of the Late Albian, giving rise to the widespread deposition of marine Upper Albian sediments. This transgressive event can also be recognised in southern Iberia and Portugal. During the later part of the Late Albian, the emergent crestal areas of the tilted blocks were onlapped by marine sediments, resulting in the filling-up of the Middle Albian palaeo-relief. Tectonic movements in the latest Albian (Vraconian tectoevent), causing emergence in wide parts of the NCB, terminated the Albian Megasequence. The Cenomanian megasequence started in the Albian/Cenomanian boundary interval with progradation of deltaic clastics, which were channelized (following the Santi liana-axis) into an eastward direction. This "Santillana Delta" flowed into the Basco-Cantabrian Basin east of Santander, where an interfingering with the prodeltaic sediments of the Valmaseda Delta ("Black Flysch" of the Bilbao area) took place. The differential subsidence in the NCB due to the Vraconian tectoevent was compensated by the deltaic sedimentation. In the lower part of the Mantelliceras mantelli Zone, a transgressive pulse flooded the NCB and led to the deposition of marine, predominantly calcareous sediments. This transgressive event is thought to correlate with the "Early Cenomanian transgression" sensu lato. In the Cenomanian succession of the NCB, the following ammonite zones can be recognized: • Late Cenomanian: Eucalycoceras pentagonum Zone and Metoicoceras geslinianum Zone [pars] • Middle Cenomanian: [Cunningtoniceras inerme Zone], Acanthoceras rhotomagense Zone and A. jukesbrownei Zone • Early Cenomanian: Mantelliceras mantelli Zone and M. dixoni-Zone. The upper part of the Upper Cenomanian (upper part of the geslinianum Zone and the Neocardioceras juddii Zone) is missing in the NCB. In the upper part of the mantelli Zone, deposition of the shallow marine carbonate sediments of the Altamira Platform became established over large areas of the NCB. In the strongly subsiding area east of the Rio Miera Flexure, thick successions of basinal sediments (marls, nodular limestones, marl/limestone rhythmites) were deposited contemporaneously. During the Middle to early Late Cenomanian, the Altamira Platform was drowned in three successive steps from east to west. The developing drowning unconformities (condensed, mineralized hardgrounds with ammonites) young towards the west, resulting in a backstepping of the Altamira Platform. In the Late Cenomanian (pentagonum Zone), all former sites of shallow marine carbonate deposition were drowned. The depositional history of the Cenomanian was terminated in the higher part of the geslinianum Zone when tectonic movements of the Santander tectoevent caused widespread emersion of the NCB. The resulting Cenomanian/Turonian boundary hiatus can be recognized both in the condensation horizons on top of the submerged platform as well as in the basinal successions. The facies development of the Cenomanian Megasequence is dominated by the pulsatory nature of the "Cenomanian transgression". Within the Cenomanian succession of northern Cantabria, six sequence boundaries can be recognized, which define six depositional (3rd-order) sequences (DS Ce I - VI). The stratigraphic positions of the sequence boundaries (SB) are as follows: • SB Ce VI = upper geslinianum Zone • SB Ce V = Middle/Late Cenomanian boundary interval • SB Ce IV = basal jukesbrownei Zone • SB Ce III = upper dixoni Zone • SB Ce II = upper mantelli Zone • SB Ce I = lower mantelli Zone. Comparison of this sequential subdivision with regional cycle charts from the Basco-Cantabrian area reveals good agreement, whereas correlation with the "global sea-level curve" (Exxon Chart) is poor. The extent to which many of the sea-level events in the Cenomanian (e.g. SB Ce III, mfz within the rhotomagense Zone, SB Ce IV, HST in the pentagonum Zone) can be correlated between basins elsewhere in Europe and Tunisia suggests that they were probably of eustatic nature. Considering the Cenomanian Megasequence as a "2nd-order cycle", an overall transgressive trend occurs throughout the Cenomanian; maximum coastal onlap was reached during the maximum flooding of DS Ce VI (pentagonum Zone). Palaeobiogeographically, the NCB shows strong tethyan affinities in the Late Albian and Cenomanian. The Turrilites scheuchzerianus/Neohibolites ultimus event in the early Middle Cenomanian permits a correlation with the Actinocamax primus event of the temperate Cenomanian of northern Europe by means of bio-, sequence and isotope stratigraphy.

Description: Los sedimentos del Cretácico medio (Albiense superior/Cenomaniense) en la parte septentrional de la Provincia de Cantabria han sido estudiados, centrándose en aspectos estratigráficos y sedimentolögicos. El área de estudio pertenece estructural mente a la Cuenca Norcantábrica (NCB), cuya historia depositional comenzó con movimientos tectónicos distensivos en el Valanginiense medio. La NCB es una de las numerosas cuencas sedimentarias que se desarrollaron en el margen continental norteibérico como consecuencia del "rifting" y apertura del golfo de Vizcaya durante el Mesozoico. Es una cuenca con forma de golfo con una elongatión E/W ("Eje de Santillana"). Los límites septentrional y meridional de la NCB son el "Liencres High" y el Escudo de Cabuemiga respectivamente. Hacia el Oeste, la NCB queda confinada por el Macizo Paleozoico Asturiano; en el Este, el límite estructural conocido como Flexión del Río Miera de dirección N/S, la separa de la Cuenca Vasco-cantábrica mucho más subsidente. La historia deposicional de la NCB estuvo fuertemente influenciada por eventos tectónicos que pueden ser relacionados con la evolution del oceano de Vizcaya. Estos tectoeventos dieron lugar a una gruesa subdivision de la sucesión en megasecuencias sedimentarias. Tres límites de megasecuencias, que están inducidos por la tectónica, pueden ser reconocidos en el Albiense y Cenomaniense, definiendo respectivamente las megasecuencias albienses y cenomanienses: • Tectoevento de Santander (intervalo límite del Cenomaniense/Turoniense) • Tectoevento Vraconiense (Albiense superior tardío) • "Evento del Albiense medio" (discordancia de ruptura, Albiense inferior [?tardio]). El "Evento del Albiense medio" causo una desintegración de las plataformas urgonianas clansayenses (Aptiense superior/Albiense inferior), que estaban muy extendidas en paleorelieves de bloques basculados hacia el Este. Se produjo durante el Albiense medio una sedimentatión clástica fluvio-deltaica en los semi-grabenes, de dirección N/S, mientras que las cimas expuestas de los bloques basculados sufrieron procesos de karstificatión. Un fuerte pulso transgresivo inundó la NCB al comienzo del Albiense superior, dando lugar al depósito de sedimentos marinos en el Albiense superior due alcanzaron una muy amplia extensión. Durante la parte superior del Albiense superior las crestas de los bloques basculados fueron recubiertas por sedimentos marinos, indicando el equilibrio del paleorelieve en el Albiense medio. Los procesos tectónicos al final del Albiense superior (Tectoevento Vraconiense), que causaron la emersión de amplias zonas de la NCB, terminan la megasecuencia albiense. La megasecuencia cenomaniense comenzó en el limite Albiense/Cenomaniense con la progradatión de material clástico deltaico que fue canalizado (siguiendo el Eje de Santillana) hacia el Este. Dicho delta ("Delta de Santillana") discurria al Este de Santander hacia la Cuenca Vasco-cantabrica, interfiriendo con los sedimentos de prodelta del Delta de Valmaseda ("Flysch Negro"). En la parte inferior de la zona de Mantelliceras mantelli, un pulso transgresivo inundó la NCB y permitió el depósito de sedimentos marinos, predominantemente calcáreos. Este evento transgresivo puede ser correlacionado con la "transgresión del Cenomaniense initial" sensu lato. En la sucesion Cenomaniense de la NCB pueden ser reconocidas las siguientes zonas: • Cenomaniense superior: Zona de Eucalycoceras pentagonum y la Zona de Metoicoceras geslinianum [pars] • Cenomaniense medio: [Zona de Cunningtoniceras inerme], Zona de Acanthoceras rhotomagense y Zona de A. jukesbrownei • Cenomaniense inferior: Zona de Mantelliceras mantelli y Zona de M. dixoni. La parte superior del Cenomaniense superior (parte superior de la zona de M. geslinianum y la Zona de Neocardioceras judii) está ausente en la NCB. Los sedimentos marino-someros de naturaleza carbonatada de la "Plataforma de Altamira" comenzaron a depositarse en amplias zonas de la NCB en la parte superior de la zona de mantelli. Al Este de la Flexión de Río Miera, en un área fuertemente subsidente, fueron depositadas contemporáneamente potentes sucesiones de sedimentos de cuenca (margas, calizas nodulares y ritmitas de marga/caliza). Durante el Cenomaniense medio hasta la base del Cenomaniense superior, la Plataforma de Altamira fue inundada desde el Este al Oeste en tres intervalos sucesivos. El desarrollo de discordancias de inundatión ("drowning unconformities" = series condensadas, "hardgrounds" mineralizados con ammonites) resultan más recientes hacia el Oeste, concluyendo en un basculamiento hacia atrás de la Plataforma de Altamira. En el Cenomaniense superior (Zona de pentagonum) todos los anteriores lugares caracterizados por el depósito de carbonates marino-someros fueron anegados. La historia deposicional del Cenomaniense acabó en la parte alta de la zona de geslinianum, cuando movimientos tectonicos del Tectoevento de Santander causaron la emersión generalizada de la NCB. El hiato resultante puede ser reconocido en los horizontes condensados a techo de las plataformas sumergidas e igualmente en las sucesiones de cuenca. El desarrollo de facies del Cenomaniense está dominado por el carácter de pulsos que tuvo la "transgresión cenomaniense". Seis límites de secuencia pueden reconocerse dentro de la sucesión cenomaniense del norte de Cantabria, los cuales definen seis secuencias deposicional es de tercer orden (DS Ce I-VI). La positión estratigráfica de los límites de secuencia (SB) son los siguientes: • SB Ce VI = parte superior de la Zona de geslinianum • SB Ce V = intervalo límite del Cenomaniense medio/superior • SB Ce IV = base de la Zona de jukesbrawnei • SB Ce III = parte superior de la Zona de dixoni • SB Ce II = parte superior de la Zona de mantelli • SB Ce I = parte inferior de la Zona de mantelli. Una comparación de esta subdivisión secuencial con las tablas de ciclos regionales del reino vasco-cantábrico revela una buena correlatión, mientras que la correlatión con la "tabla global" ("Exxon chart") es pobre. La correlatión entre varias cuencas sugiere una causa eustática para los numerosos eventos de cambios del nivel del mar en el Cenomaniense (por ejemplo SB Ce III, mfz dentro de la Zona de rhotomagense, SB Ce IV, HST en la Zona de pentagonum). Considerando la megasecuencia del Cenomaniense como un "ciclo de segundo orden", una tendencia transgresiva general ocurrió a lo largo del Cenomaniense, el máxirno "onlap" costero fue alcanzado durante la máxima inundatión de la DS Ce VI (Zona de pentagonum). Desde el punto de vista paleobiogeográfico, la NCB muestra fuertes afinidades tethyales en el Albiense superior y el Cenomaniense. El "Evento de Turrilites scheuchzerianus/Neohibolites ultimus" al comienzo del Cenomaniense medio permite una correlation con el "Evento de Actinocamax primus" del Cenomaniense de la Provincia templada norteuropea.

Description: thesis

Description: DFG, SUB Göttingen

Description: Geodetic data in plate boundary zones reflect the accrual of tectonic strain and stress, which will ultimately be released in earthquakes, and so they can provide valuable insights into future seismic hazards. To incorporate geodetic measurements of contemporary deformation into the 2022 revision of the New Zealand National Seismic Hazard Model 2022 (NZ NSHM 2022), we derive a range of strain-rate models from published interseismic Global Navigation Satellite Systems velocities for New Zealand. We calculate the uncertainty in strain rate excluding strain from the Taupō rift–Havre trough and Hikurangi subduction zone, which are handled separately, and the corresponding moment rates. A high shear strain rate occurs along the Alpine fault and the North Island dextral fault belt, as well as the eastern coast of the North Island. Dilatation rates are primarily contractional in the South Island and less well constrained in the North Island. Total moment accumulation derived using Kostrov-type summation varies from 0.64 to 2.93×1019 N·m/yr depending on method and parameter choices. To account for both aleatory and epistemic uncertainty in the strain-rate results, we use four different methods for estimating strain rate and calculate various average models and uncertainty metrics. The maximum shear strain rate is similar across all methods, whereas the dilatation rate and overall strain rate style differ more significantly. Each method provides an estimate of its own uncertainty propagated from the data uncertainties, and variability between methods provides an additional estimate of epistemic uncertainty. Epistemic uncertainty in New Zealand tends to be higher than the aleatory uncertainty estimates provided by any single method, and epistemic uncertainty on dilatation rate exceeds the aleatory uncertainty nearly everywhere. These strain-rate models were provided to the NZ NSHM 2022 team and used to develop fault-slip deficit rate models and scaled seismicity rate models.

Description: Highlights: • The interactions between vortices in a four-vortex flow field using a rotating water tank. • Driven by the strain field, non-ideal vortices stretch along the centerline, and manifest an asymmetric stretching pattern. • Non-ideal vortices disperse vorticity, accumulate filaments, and exhibit distinctive variations in anti-symmetric vorticity distribution, impacting respective merging efficiency. Abstract: Oceanic vortex merging is an important physical process for the vortex evolution and its impact on marine environment. However, limitation of the in-situ oceanic observational data of vortex merging inhabits its better understanding. This study investigates the interactions between non-ideal vortices in a four-vortex flow field in a rotating tank. We examine the merging stages of anticyclonic vortices, influenced by two other cyclonic vortices and their respective dynamical behaviors and quantify the effects of merging on vortex characteristics. The results indicate a strong shear flow between two counter-rotating vortices, which accelerates the motion of the anticyclonic vortex, while cyclonic ones exhibit greater stability. Subsequently, different stages of non-ideal vortex merging in a co-rotating framework are defined, primarily the encircling stage, rapid approaching stage, and merging vortex stage. In addition, we quantify and compare variations in morphological parameters and anti-symmetric vorticity distribution of non-ideal vortices across these stages. The stretching of vortices primarily occurs along the line connecting their centers due to the strain field exerted by neighboring vortices, resulting in an asymmetric stretching pattern in the interactions among non-ideal vortices. Furthermore, during the merging process, non-ideal vortices disperse vorticity outward and accumulate vortex filaments in the surrounding environment, leading to distinctive variations in anti-symmetric vorticity distribution, affecting their respective merging efficiency.

Description: During the last decades, the Chilean margin offshore Maule (34±S −36±S) had been reported as a highly locked and seismically quiet zone. The stress-accumulated state finished on the 27th of February 2010, when a megathrust earthquake (with Mw = 8.8) ruptured » 400 km of the Nazca-South America plate boundary. Unfortunately, up to now little was known about the seismic structure offshore Maule. In the frame of the third phase of the project SFB 574 “Volatiles and Fluids in Subduction Zones” of the Christan-Albrechts University of Kiel, seismic data was analyzed in order to obtain detailed images of the deep structure of the margin and of the outer rise. Here are presented constraints on the forearc and the subduction zone structure of the rupture area derived from seismic refraction and wide-angle data. The results show a wedge shaped body » 40 km wide with typical sedimentary velocities interpreted as a frontal accretionary prism (FAP). Landward of the imaged FAP, the velocity model shows an abrupt velocity-contrast suggesting a lithological change, which is interpreted as the contact between the FAP and the paleo accretionary prism (backstop). The backstop location is coincident with the seaward limit of the aftershocks, defining the updip limit of the co-seismic rupture and the seismogenic zone. Furthermore, the seaward limit of the aftershocks coincides with the location of the shelf break in the entire earthquake rupture area (33.5±S−38.5±S), which is interpreted as the location of the backstop along the margin. Published seismic profiles at the northern and southern limit of the rupture area also show the presence of a strong horizontal velocity gradient imaging the seismic backstop at a distance of » 30 km from the deformation front. The seismic wide-angle reflections from the top of the subducting oceanic crust constrain the location of the plate boundary offshore, dipping » 10±. The projection of the epicenter of the Maule earthquake onto our derived interplate boundary yielded a hypocenter around 20 km depth. This implies that the earthquake nucleated somewhere within the seismogenic zone, neither at its updip nor at its downdip limit. The second part of this thesis focuses on the dependency between the incoming plate’s bend faulting, lithospheric hydration and shallow outer rise seismic activity. To support the interpretation, are presented Vp and Vs seismic models obtained from wide angle seismic data and the derived 2D Poisson’s ratio distribution at the outer rise. The oceanic lithosphere shows a high degree of hydration, due to the water infiltration through the bending-related faults exposed to seawater. This process is presumably intensified bythe existence of a seamount in the area. It is concluded that the water infiltrates deep into the lithosphere, triggering shallow earthquakes in the outer rise and likely serpentinization in the mantle, estimated to be about 10%.

Description: In the past three decades, altimeter-based remote sensing has been a widely used system to estimate ocean surface currents. However, it remains a great challenge to effectively resolve scales below ∼100 km at high latitudes and ∼ 300 km at mid-latitudes. In this study, we propose a scheme that utilizes geostrophic equilibrium and surface quasigeostrophy theory (SQG) to improve surface current resolution by incorporating remote sensing sea surface temperature (SST), sea surface height (SSH), and sea surface salinity (SSS) observations. The scheme separately characterizes the larger-scale flows and smaller-scale motions of surface currents. A case study encompassing the Agulhas surface current demonstrates that the smaller-scale motions associated with temperature fronts are well captured by introducing high spatial-temporal resolution SST data. Furthermore, the reconstructed surface current is systemically evaluated by using surface drogued drifters and a Lagrangian synthetic particle tracking tool throughout the South Indian Ocean (SIO) for 2011–2015. Notably, the reconstructed zonal velocity component is closer to the drifter observations than the meridional counterpart and corresponding velocity phase. Regionally, the Antarctic Circumpolar Current (ACC) showcases superior reconstruction performance, with higher skill scores and lower Lagrangian separation distances. However, a relatively large uncertainty is observed around the Agulhas Retroflection (AR) and Greater Agulhas System (GAS), which are linked to complicated regional dynamic regimes. We finally conduct four simulation experiments to explore the effect of different SST products on surface current reconstruction within the subdomain AR. The results indicate the varying potentials of the four evaluated SST products for informing surface current applications. Specifically, the MWIRSST enhances the likelihood of particles reaching the target field, while DMI OI shortens the average deviation distance of the arrived particles.

Description: Sprat (Sprattus sprattus) is one of the most commercially exploited fish species in the Baltic Sea and expresses a pronounced seasonal migration pattern. Spawning takes place, among other places, in the Kiel Bight and Kiel Fjord in early summer. Juvenile sprat leave the nursery areas in late summer/early autumn to move to their feeding and overwintering grounds. What kind of orientation mechanisms sprat use for migration is not known yet. This study shows that juvenile sprat can use a time-compensated sun compass, heading towards the northeast, in the direction of their proposed overwintering grounds in Bornholm Basin. The sprats tested at the end of August oriented themselves in the predicted direction, whereas the sprats tested at the beginning of August only showed a random orientation. For the first time, this demonstrates the onset of migratory readiness in juvenile sprat, indicating the preparation for starting their migration.

Description: Laterally discontinuous subsea permafrost is present in the Arctic along the Beaufort Sea margin. Discontinuities within the permafrost include unfrozen zones from which fluids are free to migrate vertically or laterally, potentially accelerating permafrost degradation. This process releases greenhouse gases that further contribute to global warming. Generally, because of its contrasting viscoelastic properties compared to unfrozen sediments, permafrost can be easily detected by seismic methods. A discontinuity in subsea permafrost corresponds to the termination of a frozen layer. At this termination, seismic energy is diffracted rather than reflected or refracted. This condition is well suited for diffraction imaging. Here, we present a processing workflow to identify subsea permafrost discontinuities using the diffracted wavefield. This workflow aims to extract diffractions from seismic data collected on the continental shelf of the Canadian Beaufort Sea. The shallow water environment combined with the occurrence of subsea permafrost generates highly energetic free surface multiples that overprinted diffractions. Thus, preliminary steps of the processing flow focused on multiple attenuation. A recursive velocity analysis, starting with a 100 common-midpoint (CMP) interval and ending with a 5 CMP interval, is also performed to better capture lateral permafrost discontinuities. Then, the full wavefield data are migrated, collapsing the energy distributed along the hyperbolic trajectory of the diffractions at their apexes. Afterwards, reflections are adaptively subtracted from the migrated data. Finally, demigration of the residuals (i.e., collapsed diffractions) is performed. The resulting image reveals several near-surface diffractions attributed to discontinuities at the top of the subsea permafrost. Diffractions present distinct amplitude, frequency and velocity characteristics suggesting that various permafrost conditions coexist across the continental shelf.

Description: Mud volcanoes (MVs) have been found in various geological settings on passive and active margins but are mostly known from collision zones on Earth. Mud volcanoes are well known to occur on land (e.g. in Azerbaijan), where at least 1000 MVs have been counted. The amount of submarine MVs is believed to be much larger and recent improvements in seafloor mapping led to the discovery of many MVs in all oceans. To contribute to the knowledge of submarine MVs, in particular the internal structure across Venere MV, we conducted a multi-geophysical imaging approach using high resolution multibeam bathymetry, (constraining seafloor expressions), multichannel, and wide-angle seismic data (constraining the internal structure and P-wave velocity distribution). Venere MV is located at the southern rim of the Crotone forearc basin of the Calabrian arc, offshore southern Italy, in a water depth of ~1500 m. The dimension of Venere MV from its bathymetric expression is ~10 km in the EW- and ~7 km in the NS-direction. Two circular cones of ~100 m elevation and ~1.5 km diameter are located in the center of Venere MV. The upper 200 m below the seafloor (bsf) consist of layers with seismic P-wave velocities gradually increasing from 1.53 to 1.7 km/s (sub-) parallel to the seafloor. A prominent reflection ~200 m bsf and a sudden increase of seismic P-wave velocities from 1.7 to 1.8 km/s mark a change with depth in the internal structure, where reflections dip, and seismic P-wave velocities laterally decrease towards the center of Venere MV. The MCS as well as seismic P-wave velocity structure indicate two separate feeder conduits of the two center cones of Venere MV. However, we do not map the roots of the MV, which are at depths beyond our data resolution. Reduced reflectivity occurs ~4 km across the center of the MV 200 m bsf and downwards. We mapped the chaotic reflections of the acoustic basement in depths varying from 500 m to 800 m bsf. Reduced reflectivity of the acoustic basement occurs beneath the center of the MV as well. Mapping of the fault system leads to the subseafloor dimension of Venere MV that exceeds its seafloor dimension by the factor of two.

Description: During the last 1 Ma in the Canadian Arctic, permafrost and permafrost-associated gas hydrates formed extensively due to mean annual subaerial temperatures of approximately -20°C. Following the last glaciation, a marine transgression occurred and former terrestrially exposed shelves became inundated, resulting in present submarine bottom water temperatures around -1°C. Relict submarine permafrost and gas hydrates in the Canadian Beaufort Sea are still responding to this thermal change resulting in their ongoing degradation. Thawing of permafrost and destabilisation of permafrost-associated gas hydrates can release previously trapped greenhouse gases and can lead to even further gas hydrate dissociation with important implications for the global climate. However, both the extent of the submarine permafrost and the permafrost-associated gas hydrates are still not well known. In this study, we use marine multichannel seismic data to model the base of permafrost from the depth of the base of the gas hydrate stability zone. From this depth, we estimate the theoretical gas hydrate dissociation temperature, which allows us to model the depth of the thermal base of permafrost (0°C isotherm). The base of permafrost we modelled correlates with the lower boundary of a diffuse zone of high diffractivity in seismic data suggesting the presence of ice-bearing permafrost. These results combined show that the base of permafrost still extends close to the shelf edge indicating less permafrost retreat than previously suggested. Our study provides a different approach to accessing the current depth and extent of submarine permafrost on the outermost Canadian Beaufort Shelf.

Description: Marine imaging studies have unique constraints on the data collected requiring a tool for defining the biological scope to facilitate data discovery, quality evaluation, sharing and reuse. Defining the ‘target population’ is way of scoping biological sampling or observations by setting the pool of organisms to be observed or sampled. It is used in survey design and planning, to determine statistical inference, and is critical for data interpretation and reuse (both images and derived data). We designed a set of attributes for defining and recording the target population in biological studies using marine photography, incorporating ecological and environmental delineation and marine imaging method constraints. We describe how this definition may be altered and recorded at different phases of a project. The set of attributes records the definition of the target population in a structured metadata format to enhance data FAIRness. It is designed as an extension to the image FAIR Digital Objects metadata standard, and we map terms to other biological data standards where possible. This set of attributes serves a need to update ecological metadata to align with new remotely-sensed data, and can be applied to other remotely-sensed ecological image data.

Description: We carried out measurements of the CO2 system parameters to evaluate the impact of carbonate and nutrients' chemistry on phytoplankton populations in the Gulf of Guinea (GoG). The seasonal variations of the CO2 system parameters (fCO2, DIC, pH and TA) along with nitrates and phosphates were quantified weekly at surface (between 0 and 5 m depth) (5.57 degrees N - 4.57 degrees W) in the GoG from May to December 2020. Seawater pH varied widely during the study period, ranging between 8.10-8.35 pH units; DIC and TA varied between 1810 and 2094 mu mol kg-1, and between 2051 and 2216 mu mol-1 respectively. DIC peaks coincided with the high upwelling period (August and September). For phytoplankton, a total of 60 species were found belonging to four taxonomic phyla: Bacillariophyta, Dinophyta, Chlorophyta and Dictyochophyta. The highest number of phytoplanktonic species were recorded for Bacillariophyta phylum with 36 species (60%). The phylum Dinophyta comprised 22 taxa (36%) and Chlorophyta and Dictyochophyta recorded only one species (2%). The highest specific diversities were observed in August and September with 29 and 26 taxa respectively and the lowest was found in October-November (5 taxa) and December (one taxa). Bacillariophyta and Dinophyta appeared throughout the entire study period. The only species for Chlorophyta phylum appeared in June and July and the Dictyochophyta's one in May, July and August. In general, the physical (SST, SSS) and chemical (TA, DIC, pH) parameters influenced less than 50% of the phytoplankton population in the coastal area of the GoG. Our study shows that Bacillariophyta population grows up when the physicochemical parameters' variability increase.

Description: ALKOR cruise AL590 took place as part of the project CONMAR (https://conmarmunition.eu/) which is part of the DAM mission sustainMare (https://www.sustainmare.de/). It was the continuation of the munition monitoring started within the BMBF‐funded project UDEMM (Environmental Monitoring for the Delaboration of Munition in the Sea; https://udemm.geomar.de/), the EMFF (European Maritime and Fisheries Fund) ‐funded projects BASTA (Boost Applied munition detection through Smart data detection in and AI workflows; https://www.basta‐munition.eu) and ExPloTect (Ex‐situ, near‐real‐time detection compound detection in seawater). ALKOR worked for two weeks in the Baltic Sea in the munition dumpsites Kolberger Heide, Falshöft, in Lübeck Bight and west of Rügen. Munition sites were mapped via hydroacoustic (multibeam and synthetic aperture sonar) and visual (ROV and towed camera) methods. Water samples were taken for explosive- type compounds and eDNA analysis and sediment samples for macro faunal distribution studies. A change of crew happened on 24th March in Neustadt i.H. with support of the Coast Guard t of the federal police.

Description: In the northeastern tropical Atlantic, a region of high potential vorticity (PV) determines the size of the exchange window for the interior thermocline flow of the subtropical cell via its variations in strength and extent. Variability of this PV barrier has the potential to impact the ventilation of the tropical Atlantic on decadal timescales. Here, the impact of the North Atlantic Oscillation (NAO) on the PV barrier related to isopycnals within the thermocline of the subtropical-tropical Atlantic Ocean is assessed from Argo observations for the time period of 2006-2022. Relative to the negative NAO phase (2009-2010), during the positive NAO phase (2014-2019), the North Atlantic subtropical high and the northeast trades are intensified. Satellite-derived wind stress curl shows increased upwelling/downwelling on the equatorward/poleward side of the trade wind zone, respectively. In the subtropical-tropical Atlantic, a symmetric pattern of isopycnal heave is observed: rising isopycnals within 20 degrees N and 20 degrees S and sinking poleward of that. With rising isopycnals, the PV barrier in the northeastern tropical Atlantic becomes stronger. Analyses of geostrophic velocities and the Sverdrup streamfunction show that during the positive NAO phase there are increased equatorward velocities at thermocline level along the western boundary and reduced velocities through the interior as a result of intensified northeast trades and therefore a strengthened PV barrier. Intensified trades lead to enhanced subduction of thermocline waters and, independent of that, to a strengthened Equatorial Undercurrent transport as observed at the mooring site at 0 degrees, 23 degrees W, likely via the pulling effect of the subtropical cells. In the North Atlantic Ocean, subducted water from the subtropics has two possible pathways within the thermocline toward the equatorial region: the interior pathway and the pathway along the western boundary. The size of the exchange window between subtropics and tropics depends on the extent of a barrier zone in the eastern part of the basin that is associated with wind-driven upwelling of density surfaces. The North Atlantic Oscillation (NAO) is the dominant atmospheric climate mode in the North Atlantic and in this study, we show how the NAO impacts the barrier for the equatorward thermocline flow in the tropical Atlantic Ocean. During positive NAO phases (e.g., 2014-2019), density surfaces become shallower and strengthen the barrier, while during negative NAO phases (e.g., 2009-2010) the barrier weakens. Geostrophic velocity analysis reveals that during positive NAO phases more thermocline water is transported equatorward via the western boundary and less via the interior pathway. Additionally, observations from a mooring site at 0 degrees, 23 degrees W show stronger Equatorial Undercurrent transport as a result of intensified trade winds during positive NAO phases. Trade winds in the northeastern tropical Atlantic strengthen during positive phases of the North Atlantic Oscillation (NAO+) Potential vorticity barrier for the interior equatorward thermocline flow of the North Atlantic Subtropical Cell strengthens during NAO+ Annual subduction of thermocline water and Equatorial Undercurrent transport increase simultaneously from 2008 to 2018

Description: Variations in trace metal contents and sulfur isotope ratios (δ34S) within pyrite, at the scale of individual mineral grains, preserves a record of temporal fluctuations in the source of metals and sulfur as well as changes in the chemical composition and temperature of hydrothermal fluid during the evolution of the Brothers volcano, Kermadec arc, New Zealand. In this study, we analyzed pyrite from drill core recovered from two geochemically distinct hydrothermal systems at the Brothers volcano, the seawater-influenced NW Caldera (Site U1530) and magmatic-volatile-dominated Upper Cone (Site U1528) during the International Ocean Discovery Program’s Expedition 376. At the NW Caldera site, from 189 m below the seafloor, a seawater-derived hydrothermal fluid forming chlorite-rich alteration overprints early pyrophyllite + illite alteration. Within ~ 30 m of the seafloor at this same site, pyrite contains zones of high As content with a variable δ34S signature that ranges from -4.5 to 3.4‰ (n = 26). Values for δ34S 〉 0‰ record shallow mixing of seawater with upwelling hydrothermal fluids. In deeper parts of the system, but still within the chlorite-rich alteration zone, δ34S values 〉 0‰ are absent, indicating that relatively more sulfur is contributed from magmatic volatile degassing and SO2 disproportionation. In the pyrophyllite-rich alteration zone, pyrite contains Co-enriched cores that correspond to sharp changes in δ34S values from -5.3‰ to 4.6‰ (n = 68). Cobalt enrichment occurs in response to the mixing of seawater-derived hydrothermal fluid with Co-rich magmatic brines. At the Upper Cone site, a relatively constant supply of a low-salinity magmatic fluid results in pyrite grains that rarely exhibit any internal zonation in trace metal content. In pyrite where zonation does exist, a correlation between Cu and Sb and uniformly low δ34S values (〈 0‰) indicates a link between metal enrichment, the pulsed degassing of magmatic volatiles, and SO2 disproportionation.

Description: The question of how science can become a lever in achieving the Sustainable Development Goals permeates most recent sustainability research. Wide-ranging literature calling for a transformative approach has emerged in recent years. This ‘transformative turn’ is fueled by publications from fields such as sustainability science, social-ecological research, conservation science, sustainability transitions, or sustainability governance studies. However, there is a lack of a shared understanding specifically of what is meant for research to be transformative in this developing discourse around doing science differently to tackle sustainability problems. We aim to advance transformative research for sustainability. We define transformative research and outline six of its characteristics: (1) interventional nature and a theory of change focus; (2) collaborative modes of knowledge production, experimentation and learning; (3) systems thinking literacy and contextualization; (4) reflexivity, normative and inner dimensions; (5) local agency, decolonization, and reshaping power; (6) new quality criteria and rethinking impact. We highlight three tensions between transformative research and traditional paradigms of academic research: (1) process- and output-orientation; (2) accountability toward society and toward science; (3) methodologies rooted in scientific traditions and post-normal methodologies. We conclude with future directions on how academia could reconcile these tensions to support and promote transformative research.

Description: Dominant ways of doing research are not enough to achieve the UN Sustainable Development Goals. The typical response of science to dealing with the current local and global sustainability crises is to produce and accumulate more knowledge. Transformative research seeks to couple knowledge production with co-creating change. This paper defines the transformative way of doing research to pro-actively support society's fight against pressing societal and environmental problems. We present six characteristics of transformative research. We reflect on the challenges related to implementing these characteristics in scientific practice and on how academia can play its part.

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Description: Im Zusammenhang mit der Neuordnung der Bergverwaltung fand auch in Berggießhübel eine Besichtigung der Bergwerke statt. Aufgrund der festgestellten Unregelmäßigkeiten wurde eine neue Bergordnung erlassen. In 11 Paragrafen wurde eine ordentliche Rechnungslegung festgelegt, die Hammerherren zur pünktlichen Bezahlung des Eisensteins aufgefordert und eine strenge Kontrolle der Arbeitszeit angeordnet. Weiterhin erhielten Gewerken eine Steuererleichterung beim Stollnvortrieb.

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Description: Purpose: The surface store governs the rainwater partition, e.g., water storage and evaporation on paved surfaces, especially for low-intensity and low-sum rain events, which account for the greatest part of the total rainfall in a temperate climate city like Berlin, Germany. The surface store S is a fixed value, dependent on surface relief and pore system characteristics. Contrary, in this study, the surface storage was assumed to depend also on the rain intensity, thus being variable from event to event. Materials and methods: The surface store filling dynamics for dense (DP), porous (PP), and highly infiltrative (IP) paving materials were studied in a rainfall simulator. Irrigation intensities p ranged from 0.016 to 0.1 mm min〈sup〉−1〈/sup〉 which represent the 25 to 88% quantiles of the rain event distribution in Berlin, Germany (1961 to 1990). Results and discussion: Three surface stores can be separated: storage until initial runoff, S〈sub〉f〈/sub〉, at maximum filling, S〈sub〉m〈/sub〉, and for steady-state runoff, S〈sub〉eq〈/sub〉—all of them can be regarded as effective stores depending on the aim of its use. The equilibrium store varies from 0.2 to 3 mm for DP, PP, and IP for the investigated rainfall intensities. Conclusions: For all pavers, the surface store depends on rainfall intensity, which was shown experimentally and confirmed by numerical simulation of the infiltration. We introduce a simple and robust method to describe S〈sub〉f〈/sub〉, S〈sub〉m〈/sub〉 = f(p) for different pavers. Pavers can evaporate a multiple of their surface store per day, depending on the rainfall distribution, which implicates the need for high temporal resolutions in urban hydrology modeling. Pavers can evaporate a multiple of their surface store per day, depending on the rainfall distribution. That implicates the need for high temporal resolutions in urban hydrology modeling.

Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

Description: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Horizontal wavenumber spectra across the middle atmosphere are investigated based on density measurements with the Airborne Lidar for Middle Atmosphere research (ALIMA) in the vicinity of the Southern Andes, the Drake passage and the Antarctic peninsula in September 2019. The probed horizontal scales range from 2000 to 25 km. Spectral slopes are close to 〈italic〉k〈/italic〉〈sup〉−5/3〈/sup〉 in the stratosphere and get shallower for horizontal wavelengths 〈200 km in the mesosphere. The spectral slopes are shown to be statistically robust with the presented number of flight legs despite the unknown orientation of true wave vectors relative to the flight track using synthetic data and a Monte Carlo approach. The largest spectral amplitudes are found over the ocean rather than over topography. The 2019 sudden stratospheric warming caused a critical level for MWs and a reduction of spectral amplitudes at horizontal wavelengths of about 200 km in the mesosphere.〈/p〉

Description: Plain Language Summary: The spectral analysis of observations along extended flight tracks helps to determine the contribution of different length scales to atmospheric processes. In this study we calculate horizontal wavenumber spectra in the altitude range between 20 and 80 km, the middle atmosphere, based on observations from the Airborne Lidar for Middle Atmosphere research onboard the HALO aircraft. The observations were performed in the vicinity of the Southern Andes, the Drake passage and the Antarctic peninsula during September 2019. The observed horizontal scales range from 2000 km to about 25 km and cover almost the entire mesoscale range of atmospheric dynamics in the middle atmosphere. This study finds that vertical oscillations in the atmosphere, called gravity waves, cause the slopes and power of the spectra at the observed horizontal scales in the middle atmosphere. The slopes and power of the horizontal spectra vary with varying gravity wave activity during the period of observations.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉Horizontal wavenumber spectra across the middle atmosphere are computed using airborne lidar observations during the 2019 sudden stratospheric warming (SSW)〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Horizontal wavenumber spectra are close to 〈italic〉k〈/italic〉〈sup〉−5/3〈/sup〉 in the stratosphere, and become shallower in the mesosphere during the SSW〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Observational evidence is provided that the mesoscale spectral slope in the middle atmosphere is caused by the occurrence of gravity waves〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: German Federal Ministry for Education and Research

Description: Internal Funds of the German Aerospace Center

Description: Karlsruhe Institute of Technology

Description: Forschungszentrum Jülich

Description: German Science Foundation

Description: https://doi.org/10.5281/zenodo.7861915

Description: Einer Anregung des 11. Arbeitskurses Niederdollendorf folgend, wurde eine Methode der Bearbeitung farbiger Originale kartographischer Landschaftsdarstellung entwickelt und erprobt. Eine erste Bestandsaufnahme hatte einen Bedarf an solchen Darstellungen bestätigt; geeignete Techniken stehen zur Verfügung, es fehlt jedoch eine lern- und lehrbare Methode der Bearbeitung, die unabhängig von der Person des Bearbeiters vergleichbare Ergebnisse liefert. Hier wurde nun ein in der thematischen Kartographie als Anleitung zu planmäßigen Vorgehen bewährtes System von Arbeitsschritten mit einigen Modifikationen als Richtlinie für die Bearbeitung von Landschaftskarten eingesetzt. Nicht zuletzt wird die Arbeitsweise von den verfügbaren Unterlagen beeinflußt und entweder der Ableitung topographischer Folgemaßstabskarten oder der freien Bearbeitung thematischer Karten entsprechen.

Description: According to a suggestion made by the 11th study group of Niederdollendorf a method of how to treat coloured originals of cartographic landscape representation has been developed and testet. A first stocktaking had confirmed the demand for such types of representation; although suitable techniques are available, a learnable and teachable method of treatment is needed which provides comparable results independent of the person incharge. In this case a slightly modified system of working steps has been used as a guideline for the treatment of maps which is a time-tested instruction for systematic procedure in thematic cartography. This method is not least influenced by the available records, corresponding either to a derivation of topographic maps on a consecutive scale or to the free treatment of thematic maps.

Description: PUHLMANN, G.: Eine Methode der Bearbeitung farbiger Originale kartographischer Landschaftsdarstellung ... 5 ; KOCHLER, J.: "Landschaften" in China und die Präzisierung dieser Kategorie in verschiedenen Typologien zur Gliederung des chinesischen Territoriums ... 13 ; STRAUB, W.: Eine Vegetationskarte der Volksrepublik China ... 23 ; MERTINS, M.: Eine Landschaftskarte der Volksrepublik China ... 71 ; BETKE, D. : Anmerkungen zu zwei kartographischen Neuerscheinungen zur Landnutzung und Vegetation der VR China ... 123 ;

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Description: DFG, SUB Göttingen

Description: The stable water isotopic composition in firn and ice cores provides valuable information on past climatic conditions. Because of uneven accumulation and post‐depositional modifications on local spatial scales up to hundreds of meters, time series derived from adjacent cores differ significantly and do not directly reflect the temporal evolution of the precipitated snow isotopic signal. Hence, a characterization of how the isotopic profile in the snow develops is needed to reliably interpret the isotopic variability in firn and ice cores. By combining digital elevation models of the snow surface and repeated high‐resolution snow sampling for stable water isotope measurements of a transect at the East Greenland Ice‐core Project campsite on the Greenland Ice Sheet, we are able to visualize the buildup and post‐depositional changes of the upper snowpack across one summer season. To this end, 30 cm deep snow profiles were sampled on six dates at 20 adjacent locations along a 40 m transect. Near‐daily photogrammetry provided snow height information for the same transect. Our data shows that erosion and redeposition of the original snowfall lead to a complex stratification in the δ〈sup〉18〈/sup〉O signature. Post‐depositional processes through vapor‐snow exchange affect the near surface snow with d‐excess showing a decrease in surface and near‐surface layers. Our data suggests that the interplay of stratigraphic noise, accumulation intermittency, and local post‐depositional processes form the proxy signal in the upper snowpack.

Description: Plain Language Summary: We study the process of the formation of the stable water isotope signal in surface snow on the Greenland Ice Sheet to better understand temperature information which is stored as a climate proxy in snow and ice. Our data consist of high‐resolution surface topography information illustrating the timing and location of snowfall, erosion, and redeposition along a transect of 40 m, as well as stable water isotope records of the upper 30 cm of the snowpack sampled biweekly on 20 positions at the same 40 m long transect. The data cover a 2‐month period during the summer of 2019. We find that the isotopic composition shows spatial variability of layers with low and high values, presumably winter and summer layers. We further observe that prevailing surface structures, such as dunes, influence the snow deposition and contribute to the found variable structure of the climatic information. Eventually, snow accumulation alone cannot explain all of the observed patterns in the isotopic data which is likely related to exchange processes between the snow and the atmosphere which modify the signal in the snow column after deposition.

Description: Key Points: Combining digital elevation models and repeated snow sampling reveals the heterogeneous buildup of δ〈sup〉18〈/sup〉O signal in the snow column. Surface structures (stratigraphic noise) substantially contribute to internal heterogeneity in δ〈sup〉18〈/sup〉O signature in the upper snowpack. Proxy signals are formed in the surface layer by local processes, advected downwards with limited post‐depositional influences below 10 cm.

Description: Horizon 2020 Framework Programme http://dx.doi.org/10.13039/100010661

Description: A. P. Møller Foundation, University of Copenhagen

Description: US National Science Foundation, Office of Polar Programs

Description: Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research

Description: National Institute of Polar Research and Arctic Challenge for Sustainability

Description: University of Bergen

Description: Trond Mohn Foundation

Description: Swiss National Science Foundation

Description: French Polar Institute Paul‐Emile Victor, Institute for Geosciences and Environmental Research

Description: University of Manitoba

Description: Chinese Academy of Sciences

Description: Beijing Normal University

Description: https://doi.org/10.1594/PANGAEA.954944

Description: https://doi.org/10.1594/PANGAEA.954945

Description: https://doi.org/10.1594/PANGAEA.951583

Description: https://doi.org/10.1594/PANGAEA.925618

Description: https://doi.org/10.1594/PANGAEA.928827

Description: https://www.agisoft.com/downloads/installer/

Description: VORWORT ... 1 ; INHALTSVERZEICHNIS ... 2 ; 1 PÖHLMANN, G.: Basiskarten arider Gebiete ... 3 ; 2 MEISSNER, B.: Topographische Interpretation von Fernerkundungsdaten für "Basiskarten zur thematischen Kartierung arider Gebiete" ... 57 ; 3 MEISSNER, B. & RIPKE, U. : Luft- und Satellitenbild-Interpretation für die Karte "MUT 1 : 100 000"... 69 ; 4 KRAMER, G.: Topographische Ergänzungsmessungen ... 85 ; 5 RIPKE, U.: Die Herstellung des Kartenblattes MUT 1 : 100 000 ... 97 ; 6 ZIRN, V.: Höhenlinienstudie South Bir Tarfawi ... 105 ;

Description: research

Description: DFG, SUB Göttingen

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉Heavy‐mineral suites are used widely in sandstone provenance and are key when connecting source and sink. When characterizing provenance related signatures, it is essential to understand the different factors that may influence a particular heavy‐mineral assemblage for example, chemical weathering or diagenetic processes. Hydrodynamics, causing size‐density sorting, exert major control on the distribution of heavy minerals. Here, we highlight the effect of grain‐size inheritance, essentially the absence of certain grain sizes within a specific heavy‐mineral species, on two distinct types of sediments. Modern deposits from a high‐energy beach in NW Denmark give an analog for heavily reworked sediment, primarily controlled by hydrodynamic processes. In contrast, three Palaeogene turbidite successions in the Eastern Alps were sampled, presenting a more complex history that includes diagenesis. All samples were processed for their heavy‐mineral compositions using Raman spectroscopy, and several techniques applied to determine the effect of grain‐size inheritance. Results show that (a) even within the hydrodynamically well‐sorted beach and placer deposits, evidence of grain‐size inheritance is apparent, and (b) turbidites of variable heavy‐mineral composition show strong effects of grain‐size inheritance for several mineral species. Moreover, considerable intersample contrasts within single turbidite beds are observed. We enforce the importance of understanding grain‐size inheritance, as well as other processes effecting size‐density relations in clastic sediment that go well beyond purely hydrodynamic control of intrasample heavy‐mineral variability.〈/p〉

Description: Plain Language Summary: Heavy minerals are commonly found within sediments and sedimentary rocks and can tell us from which source regions the sediment may have originated. However, it is important to understand that the type, size, and abundance of particular heavy minerals can change depending on factors such as environmental conditions. The size, shape, and density of the heavy minerals also limits when and where they will settle and/or stay. A lack of big or small grains of a particular heavy mineral in the source rocks dictates the size of the minerals deposited; this is known as grain‐size inheritance. Using both ancient and modern sediment, we are looking for traces of grain‐size inheritance. Surprisingly, in all samples investigated we noted effects of grain‐size inheritance, for different heavy‐mineral types. The modern beach sediments, as expected, show more impact of hydraulic processes, but inherited grain sizes are still apparent. Within the ancient examples, grain‐size inheritance is more obvious, with further variations even observed between samples collected from the same area. Having identified this control on grain size, we can highlight the importance of understanding this effect when analyzing clastic sediments.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉Understanding factors that can modify a heavy‐mineral assemblage is fundamental in provenance analysis〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Heavy minerals of two distinct sedimentary environments were analyzed and compared to their “ideal” hydrodynamically sorted compositions〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉Several heavy‐mineral species of modern and ancient settings were identified to be influenced by grain‐size inheritance from the source〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: https://doi.org/10.25625/MVUIJQ

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉The transboundary region of the Iishana system in the western Cuvelai Basin, between southern Angola and northern Namibia, is frequently affected by floods at irregular intervals. As a result, the predominantly rural, subsistence farming population has experienced crop failures, human, and economic losses. To date, very little is known about the generation of floods, flood concentration, and stormwater drainage dynamics in this region. In this study, 2D‐hydrodynamic modeling was applied to reconstruct one of the latest major flood events during the rainy season from November 2008 to March 2009 in order to study the runoff behavior and interconnectivity of the Iishana system. The model focused on the eastern part of the Iishana system, which was most affected by floods and flood damage due to the high population density in and around Oshakati, the regional capital. Two main streams were identified noteworthy because they merge and subsequently affect Oshakati. Regarding the simulated flood event water depths vary from 0.1 m to 14 m, with an average of 0.2 m, while water depths above 5 m were attributed to borrow pits. The inundation area ranged up to 1860 km〈sup〉2〈/sup〉 and the amount of water left after the rainy season on March 25th, 2009, was determined between 0.116 and 0.547 km〈sup〉3〈/sup〉, depending on the amount of evapotranspiration considered in the model. Thus, in the Angolan part of the Iishana system, significantly larger quantities of water are available for longer periods of time during the subsequent dry season, whereas the system in Namibia stores less water, resulting in a shorter water retention period.〈/p〉

Description: Deutsche Hydrologische Gesellschaft (DHG)

Description: Freie Universität Berlin http://dx.doi.org/10.13039/501100007537

Description: https://dx.doi.org/10.17169/refubium-35737

Description: 〈title xmlns:mml="http://www.w3.org/1998/Math/MathML"〉Abstract〈/title〉〈p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en"〉The Ismenius Lacus region of Mars has a diverse geological history, and we present the first high‐resolution map of Deuteronilus Cavus (36.2°N; 14.0°E, ∼120 km diameter) in the fretted terrain south of the dichotomy boundary. Strong evidence suggests a volcanic origin of the regional plains, based on the ∼50 m thick volcanic bed underlying 180–300 m of sublimation residue associated with Amazonian plateau glaciation. Pervasive external volcanic flooding, internal erosional modification, and enlargement of a pre‐existing crater by up to 175%–200% resulted in the cavus' present shape. The phyllosilicates detected within Deuteronilus Cavus could be primary materials associated with the surficial aqueous activity, subsurface alteration products excavated by impacts, or a combination of both. We observe branching fluvial channels that are more recent than the traditional valley networks and may be related to fretted terrain resurfacing during the waning period of a high‐obliquity glaciation phase. This is consistent with our interpretation of the ∼600 m thick lobate and lineated deposits, which are remnants of receding glaciers. The glacial ice, protected by a 15–20 m insulating layer of debris cover, is of significant interest for future landing missions because of its potential to preserve biological and climatological signatures, to provide a critical test of Amazonian plateau glaciation, and to be used for in situ resource utilization. With our detailed geological mapping, we improved our understanding of the geological evolution and climatic conditions in the enigmatic fretted terrain near the dichotomy boundary.〈/p〉

Description: Plain Language Summary: The ∼120 km long Deuteronilus Cavus was initiated by an impact event. The resulting impact crater was modified by glacial erosional and fluvial processes, leading to the enlargement of 175%–200% of the pre‐existing crater. In addition, we find strong evidence for recent glaciation (〈1 Ga) that left 180–300 m of sublimation residue on the plateau superimposed on a ∼50 m thick volcanic bed, suggesting a volcanic origin of the regional plains. During the waning period of a high‐glacial phase, the meltwater ponded on the surface of the cavus, altered surface rocks to produce phyllosilicates, formed channels (now observed as inverted sinuous ridges), and locally distributed branched fluvial channels that are more recent than the traditional valley networks. Glacial landforms still contain up to 600 m of remnant ice from the retreating glaciers at the end of the last glacial period. The relatively pure ice, protected by a 15–20 m insulating layer of debris cover, is critical for future landing missions because of its potential to preserve biological and climatological signatures and to be used for in situ resource utilization. Overall, this research enhances our understanding of the geological evolution and climatic history of Mars.〈/p〉

Description: Key Points: 〈list list-type="bullet"〉 〈list-item〉 〈p xml:lang="en"〉We have produced the first high‐resolution map of Deuteronilus Cavus in the fretted terrain south of the Martian dichotomy boundary〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉The region records a complex erosional and depositional history, including fluvial and glacial processes in the Amazonian period〈/p〉〈/list-item〉 〈list-item〉 〈p xml:lang="en"〉This study provides a framework for exploration of high‐obliquity mid‐latitude plateau glaciation〈/p〉〈/list-item〉 〈/list〉 〈/p〉

Description: Deutsches Zentrum für Luft‐ und Raumfahrt http://dx.doi.org/10.13039/501100002946

Description: https://doi.org/10.5281/zenodo.8205276

Description: https://doi.org/10.17189/1520332

Description: https://doi.org/10.17189/1520266

Description: https://doi.org/10.17189/1520303

Description: https://doi.org/10.5270/esa-pm8ptbq

Description: MEISSNER, B.: Fernerkundung bei der Grünplanung für die Stadtregion Berlin (West) ... 5 ; FIETZ, M. & MEISSNER, B.: Zur Auswertung von Color-Infrarot-Luftbildem (Berlin/West 1979) bei der Vegetationskartierung ... 23 ; FÖRSTER, U.: Vitalitätsbestimmung von Straßenbäumen. - Erfahrungen und Ergebnisse der Color-Infrarot-Bef 1 iegung in Berlin (West) 1979 ... 43 ; FIETZ, M.: Lebensbedingungen von Straßenbäumen in Berlin-Neukölln ... 53 ; BALTSCHUN, M. : Botanischer Garten - Karte der Gehölze - 1 : 1250 ... 65 ; BORYS, 6.: Karte zum Straßenbaumkataster - Berlin (West) - 1 : 2000 ... 101 ; ZEUNERT, C.: Karte zur Grünflächenplanung Berlin (West) - 1 : 4000 ... 121 ; MEISSNER, B.: Grünverteilung in Berlin (West) 1 : l0 000, eine Inventur - Bestandsaufnahme städtischer Vegetation mit Hilfe von reprotechnischen Mitteln und stark limitierter Bildinterpretation durch Color-Infrarot-Luftbilder... 141 ; MEISSNER, B., DOBBRICK, K. & MUNIER, C.: Satelliten-Fernerkundungs-Daten für städtische Grünübersicht? - Zur Einsatzfähigkeit von multispektralen Landsat-Scanner-Daten für jährliche Übersichts-Inventuren des Stadtgrüns von Berlin (West) ... 147 ; ANHANG ... 153 ;

Description: research

Description: DFG, SUB Göttingen

Description: Tropical peat swamp forests are wetland ecosystems characterized by peat accumulation from partially decomposing organic matter in lowland areas. In southeast Asia, tropical peat swamps account for about 11-14% of the carbon stored in all peatlands. However, converting these ecosystems for agricultural activities has potential implications for releasing materials, including trace elements. This study explores the interplay of anthropogenic activities and trace element export to the estuaries and coastal waters. The result indicated the role of pH, salinity, dissolved organic carbon (DOC), and iron (Fe) and manganese (Mn) oxides in regulating the global biogeochemical cycling of trace elements. Seasonal variabilities contribute to trace element fluxes, especially during the wet season (December), with implications for material supplies to the coastal waters. The NICA- Donnan model was used to investigate the combined impact of DOC and pH on the formation of solid iron hydroxide (Fe(OH)3(s)). The Maludam River was predicted to be supersaturated for Fe hydroxides, and the field results affirmed our model prediction. The output showed Fe and Cu had a strong affinity for DOC and, to a lesser extent, Al and Ni in the conditions prevailing at the study sites. Furthermore, the concentration of DOC (12000 μmol L−1) in the natural peat increased, while the concentration of trace elements increased in the disturbed peat. Porewater samples from the disturbed and natural peat also indicated enhanced trace element concentrations in the disturbed peat compared to the natural peat. The observed increase in trace element concentrations reflects the impact of peat conversion on agricultural activities and catchment chemistry.

Description: El Niño events are characterized by surface warming of the tropical Pacific Ocean and weakening of equatorial trade winds that occur every few years. Such conditions are accompanied by changes in atmospheric and oceanic circulation, affecting global climate, marine and terrestrial ecosystems, fisheries and human activities. The alternation of warm El Niño and cold La Niña conditions, referred to as the El Niño–Southern Oscillation (ENSO), represents the strongest year-to-year fluctuation of the global climate system. Here we provide a synopsis of our current understanding of the spatio-temporal complexity of this important climate mode and its influence on the Earth system.

Description: Understanding the behavioural ecology of endangered taxa can inform conservation strategies. The activity budgets of the loggerhead turtle Caretta caretta are still poorly understood because many tracking methods show only horizontal displacement and ignore dives and associated behaviours. However, time-depth recorders have enabled researchers to identify flat, U-shaped dives (or type 1a dives) and these are conventionally labelled as resting dives on the seabed because they involve no vertical displacement of the animal. Video- and acceleration-based studies have demonstrated this is not always true. Focusing on sea turtles nesting on the Cabo Verde archipelago, we describe a new metric derived from magnetometer data, absolute angular velocity, that integrates indices of angular rotation in the horizontal plane to infer activity. Using this metric, we evaluated the variation in putative resting behaviours during the bottom phase of type 1a dives for 5 individuals over 13 to 17 d at sea during a single inter-nesting interval (over 75 turtle d in total). We defined absolute resting within the bottom phase of type 1a dives as periods with no discernible acceleration or angular movement. Whilst absolute resting constituted a significant proportion of each turtle’s time budget for this 1a dive type, turtles allocated 16−38% of their bottom time to activity, with many dives being episodic, comprised of intermittent bouts of rest and rotational activity. This implies that previously considered resting behaviours are complex and need to be accounted for in energy budgets, particularly since energy budgets may impact conservation strategies. © The authors 2021. Open Access under Creative Commons by Attribution Licence. Use, distribution and reproduction are unrestricted. Authors and original publication must be credited