Karlsruhe Institute of Technology

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    Assessing the Spatial Similarity of Soil Moisture Patterns and Their Environmental and Observational Drivers from Remote Sensing and Earth System Modeling Across Europe

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    Soil moisture is an essential climate variable exhibiting strong spatio-temporal dynamics, especially in the topsoil. Therefore, it is assessed multiple times by sensors within in situ networks, satellites, and by modeling of the Earth system. The resulting soil moisture fields from all methods are individual and non-congruent due to the imperfection of the methods and retrievals. But their spatial patterns have valuable similarities that call for investigation to foster intercomparison or even fusion of soil moisture products. In this research study, the similarity of spatial soil moisture patterns between passive microwave remote sensing products and Earth system modeling is investigated. We configure and apply spatial similarity metrics to enable a spatial comparison of the operational SMAP Dual Channe Algorithm (DCA) radiometer soil moisture product with the soil moisture output from IFS model runs of the ECMWF. The pattern assessment spans over the whole of Europe and aims to find the drivers behind the spatial soil moisture distributions at scales ranging from single grid cells (minimum) to continental (maximum) spatial scales, and between growing periods of wet (2021) and dry (2022) years. The two specifically configured metrics, total disagreement and mean category distance, showcase the opportunities and challenges when assessing spatial similarity in soil moisture fields across different scales. In addition, the potential drivers of the spatial moisture patterns were screened. Here, soil texture is the most influential single driver of spatial patterns in the IFS soil moisture runs, when analyzed in absolute terms [m3^3 m3{-3}]. In relative terms of soil moisture [-] (soil wetness index), precipitation and soil temperature explain most of the variability of the IFS soil moisture for Europe. The SMAP retrievals are predominantly driven by the brightness temperatures, mostly influenced by surface temperature, vegetation water content, and soil roughness. These differences in drivers, as well as in methodology, culminate in an inherent discrepancy between the two soil moisture products. However, the assessment of their spatial patterns reveals the underlying similarity from the local to the continental scale

    Fukushima pays de neige – Souvenirs du Vendredi 11 Mars 2011

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    Diese narrative Reflexion erkundet das Zusammenspiel von persönlicher Erinnerung, kultureller Wahrnehmung und Umweltkatastrophe am Beispiel des Tōhoku-Erdbebens, des Tsunamis und der Nuklearkatastrophe von Fukushima am 11. März 2011. Unter Rückgriff auf literarische Bezüge wie Yasunari Kawabatas Schneeland sowie auf eigene Erlebnisse untersucht der Text, wie natürliche und vom Menschen verursachte Katastrophen Landschaften – sowohl physische als auch psychische – umgestalten. Die Träume und Erinnerungen des Autors, verwoben mit historischen und wissenschaftlichen Quellen, offenbaren die Verletzlichkeit menschlicher Infrastrukturen und die anhaltende Macht der Natur, von Vulkanausbrüchen (z. B. Capelinhos, Pico, Ätna) bis hin zu Küstenüberflutungen (z. B. Leucate, Tōhoku). Die Analyse erstreckt sich auf die politischen und gesellschaftlichen Reaktionen in Deutschland und Frankreich, die nach Fukushima unterschiedliche Wege in ihrer Atompolitik einschlugen, und unterstreicht die globale Verwundbarkeit gegenüber Naturgefahren und technologischem Versagen. Durch die Verbindung poetischer Bilder, wissenschaftlicher Literatur und kritischer Kommentare leistet diese Arbeit einen Beitrag zur Debatte über Umweltrisiken, kulturelle Traumata und die Rolle der Erinnerung im Verständnis von Katastrophen

    Core–shell Fe3_3O4_4@CoFe2_2O4_4 nanoparticles as high-performance anode catalysts for enhanced oxygen evolution reaction

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    Water electrolysis is a promising and environmentally friendly means for renewable energy storage. Recent progress in the development of anion exchange membranes (AEMs) has provided new perspectives for high-performance anode catalysts based on transition metal oxides (TMOs) for the sluggish anodic oxygen evolution reaction (OER). Here, we report on core–shell nanoparticles (Fe3_3O4_4@CoFe2_2O4_4) which allow combining an electrocatalytic shell (CoFe2_2O4_4) with a conductive core (Fe3_3O4_4). Such an original approach significantly minimizes critical Co content in the catalyst and avoids addition of unstable conductive carbon black. The core–shell nanoparticles outperform Co(1x)_{(1−x)}Fe(2+x)_{(2+x)}O4_4 nanoparticles and show an exceptional OER activity per Co unit mass (2800 A gcobalt_{cobalt}1^{−1} at 1.65 V vs. RHE) suggesting synergistic interaction between the core and the shell. Along with the core–shell structure, the size of the Fe3O4 core is a critical parameter, with a large conductive Fe3_3O4_4 core being beneficial for OER enhancement

    First experiments at the new thermohydraulic facility

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    From minerals to dollars: A scrutiny of lithium-ion battery cost models

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    The accelerating growth of electric mobility and stationary storage has intensified demand for lithium-ion bat- teries, where raw materials represent 50–70% of total cost. Volatility in Ni, Co and Li markets therefore poses major risks for affordability and investment decisions. This study systematically evaluates existing battery-cost models with a specific focus on how raw-material price inputs are represented, standardized and propagated into final /kWhoutputs.Acomparativereviewofsixteenrepresentativemodels,includingBatPaC,GREET®,EverBattandCellEST,investigatesmethodologicalassumptions,costelementstructure,andtransparencyofdatasources.Thisworkprovidesthefirstreviewthatjointlyanalysesdeterministiccostmodelsalongsideprobabilisticvalidationusingrealworldcommodityvolatility.Robustnessisassessedthrougha1,000runMonteCarlosimulationbasedonhistoricalpricedistributionsofkeymetals.Resultsindicatecleardifferentiationamongchemistries.NMC111exhibitsthewidest595rangeduetocobaltsensitivity,whereasNMC811andNMC9525shownarrowerbandsreflectingreducedcobaltexposure.Bottomupprocessbasedmodelsofferstrongercosttraceabilityandbetteruncertaintyrepresentationthantopdownmacroforecasts,whichoftenlackexplicitlinkagesto/kWh outputs. A comparative review of sixteen representative models, including BatPaC, GREET®, EverBatt and CellEST, investigates methodological assumptions, cost-element structure, and transparency of data sources. This work provides the first review that jointly analyses deterministic cost models alongside probabilistic validation using real-world commodity volatility. Robustness is assessed through a 1,000-run Monte Carlo simulation based on historical price distributions of key metals. Results indicate clear differentiation among chemistries. NMC-111 exhibits the widest 5–95% uncertainty range due to cobalt sensitivity, whereas NMC-811 and NMC-9525 show narrower bands reflecting reduced cobalt exposure. Bottom-up process-based models offer stronger cost traceability and better uncertainty representation than top-down macro forecasts, which often lack explicit linkages to /kWh outputs. Findings demonstrate that raw-material price treatment strongly influences forecast accuracy, and that scenario-free point estimates sys- tematically under-represent market risk. To address these gaps, the study proposes a structured multi-source data acquisition strategy integrating public databases, commodity-market feeds and industry publications. The review enhances transparency, establishes reproducible comparison criteria, and quantifies price-volatility effects, offering actionable guidance for re- searchers, analysts and policymakers aiming to improve reliability and reduce uncertainty in LIB cost assessment

    Dimensions of Register Variation in Contemporary German

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    Dieser Artikel präsentiert die erste vollständige multidimensionale (MD) Analyse des gesprochenen und geschriebenen Deutschen. Während frühere MD-Studien sich auf Englisch, Spanisch und Portugiesisch konzentrierten, blieb Deutsch bislang unerforscht. Unsere Untersuchung stützt sich auf einen Korpus von über 3.000 Texten, die sich auf 52 Varietäten verteilen. Der Korpus wurde mit drei Part-of-Speech-Taggern annotiert, wodurch über sechzig lexikogrammatikalische Variablen extrahiert werden konnten. Durch explorative Faktorenanalyse wurden fünf Faktoren aufgedeckt, die durch die Interpretation einer großen Anzahl von Texten hinsichtlich ihrer zugrunde liegenden kommunikativen Funktionen wie folgt bezeichnet wurden: (1) Prozessualität vs. Reifikation, (2) involvierte vs. informative Produktion, (3) offene Ausdrucksweise der Überzeugung, (4) Evidentialitätsstrategie und (5) narrativer Diskurs. Diese Dimensionen erklären bis zu 78,1 % der Varianz zwischen den Registern. Abschließend vergleichen wir die deutschen Dimensionen mit denen, die für Englisch, Spanisch und Portugiesisch berichtet wurden. Wesentliche Unterscheidungen wie mündlich/schriftlich und narrativ/nicht-narrativ treten in allen Sprachen auf, was ihren Status als potenzielle sprachübergreifende dimensionale Universalien untermauert, während Deutsch sprachspezifische Konfigurationen im evidentialen Diskurs aufweist

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