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The need for carbon-emissions-driven climate projections in CMIP7
No full textPrevious phases of the Coupled Model Intercomparison Project (CMIP) have primarily focused on simulations driven by atmospheric concentrations of greenhouse gases (GHGs), for both idealized model experiments and climate projections of different emissions scenarios. We argue that although this approach was practical to allow parallel development of Earth system model simulations and detailed socioeconomic futures, carbon cycle uncertainty as represented by diverse, process-resolving Earth system models (ESMs) is not manifested in the scenario outcomes, thus omitting a dominant source of uncertainty in meeting the Paris Agreement. Mitigation policy is defined in terms of human activity (including emissions), with strategies varying in their timing of net-zero emissions, the balance of mitigation effort between short-lived and long-lived climate forcers, their reliance on land use strategy, and the extent and timing of carbon removals. To explore the response to these drivers, ESMs need to explicitly represent complete cycles of major GHGs, including natural processes and anthropogenic influences. Carbon removal and sequestration strategies, which rely on proposed human management of natural systems, are currently calculated in integrated assessment models (IAMs) during scenario development with only the net carbon emissions passed to the ESM. However, proper accounting of the coupled system impacts of and feedback on such interventions requires explicit process representation in ESMs to build self-consistent physical representations of their potential effectiveness and risks under climate change. We propose that CMIP7 efforts prioritize simulations driven by CO2 emissions from fossil fuel use and projected deployment of carbon dioxide removal technologies, as well as land use and management, using the process resolution allowed by state-of-the-art ESMs to resolve carbon–climate feedbacks. Post-CMIP7 ambitions should aim to incorporate modeling of non-CO2 GHGs (in particular, sources and sinks of methane and nitrous oxide) and process-based representation of carbon removal options. These developments will allow three primary benefits: (1) resources to be allocated to policy-relevant climate projections and better real-time information related to the detectability and verification of emissions reductions and their relationship to expected near-term climate impacts, (2) scenario modeling of the range of possible future climate states including Earth system processes and feedbacks that are increasingly well-represented in ESMs, and (3) optimal utilization of the strengths of ESMs in the wider context of climate modeling infrastructure (which includes simple climate models, machine learning approaches and kilometer-scale climate models).Horizon 2020Biological and Environmental ResearchDeutsche ForschungsgemeinschaftPeer Reviewe
Permafrost and Active Layer Temperature and Freeze/Thaw Timing Reflect Climatic Trends at Bayelva, Svalbard
No full textPermafrost warming has been observed all around the Arctic, however, variations in temperature trends and their drivers remain poorly understood. We present a comprehensive analysis of climatic changes spanning 25 years (1998–2023) at Bayelva (78.92094°N, 11.83333°E) on Spitzbergen, Svalbard. The quality controlled hourly data set includes air temperature, radiation fluxes, snow depth, rainfall, active layer temperature and moisture, and, since 2009, permafrost temperature. Our Bayesian trend analysis reveals an annual air temperature increase of 0.9 ± 0.5°C/decade and strongest warming in September and October. We observed a significant shortening of the snow cover by −14 ± 8 days/decade, coupled with reduced winter snow depth. The active layer simultaneously warmed by 0.6 ± 0.7°C/decade at the top and 0.8 ± 0.5°C/decade at the bottom. While the soil surface got drier, in particular during summer, soil moisture below increased in accordance with the longer unfrozen period and higher winter temperatures. The thawed period prolonged by 10–15 days/decade at different depths. In contrast to earlier top‐soil warming, we observed stable temperatures since 2010 and only little permafrost warming (0.14 ± 0.13°C/decade). This is likely due to recently stable winter air temperature and continuously decreasing winter snow depth. This recent development highlights a complex interplay among climate and soil variables. Our distinctive long‐term data set underscores (a) the changes in seasonal warming patterns, (b) the influential role of snow cover decline, and (c) that air temperature alone is not a sufficient indicator of change in permafrost environments, thereby highlighting the importance of investigating a wider range of parameters, such as soil moisture and snow characteristics.Helmholtz Einstein International Berlin Research School in Data SciencePeer Reviewe
Bulk-suppressed and surface-sensitive Raman scattering by transferable plasmonic membranes with irregular slot-shaped nanopores
No full textAll authors: Roman M. Wyss; Günter Kewes; Pietro Marabotti; Stefan M. Koepfli; Karl-Philipp Schlichting; Markus Parzefall; Eric Bonvin; Martin F. Sarott; Morgan Trassin; Maximilian Oezkent; Chen-Hsun Lu; Kevin-P. Gradwohl; Thomas Perrault; Lala Habibova; Giorgia Marcelli; Marcela Giraldo; Jan Vermant; Lukas Novotny; Martin Frimmer; Mads C. Weber; Sebastian Heeg
The article processing charge was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 491192747 and the Open Access Publication Fund of Humboldt-Universität zu Berlin.Raman spectroscopy enables the non-destructive characterization of chemical composition, crystallinity, defects, or strain in countless materials. However, the Raman response of surfaces or thin films is often weak and obscured by dominant bulk signals. Here we overcome this limitation by placing a transferable porous gold membrane, (PAuM) on the surface of interest. Slot-shaped nanopores in the membrane act as plasmonic antennas and enhance the Raman response of the surface or thin film underneath. Simultaneously, the PAuM suppresses the penetration of the excitation laser into the bulk, efficiently blocking its Raman signal. Using graphene as a model surface, we show that this method increases the surface-to-bulk Raman signal ratio by three orders of magnitude. We find that 90% of the Raman enhancement occurs within the top 2.5 nm of the material, demonstrating truly surface-sensitive Raman scattering. To validate our approach, we quantify the strain in a 12.5 nm thin Silicon film and analyze the surface of a LaNiO3 thin film. We observe a Raman mode splitting for the LaNiO3 surface-layer, which is spectroscopic evidence that the surface structure differs from the bulk. These results validate that PAuM gives direct access to Raman signatures of thin films and surfaces.Peer Reviewe
Professionelle Handlungskompetenzen durch Begriffsentwicklung auf empirischer Basis
No full textDer Text beschäftigt sich mit der Notwendigkeit einer ausdifferenzierten Begriffsbildung für eine trägerübergreifende professionelle Verständigung. Dieses setzt voraus, dass die Forschung den Gegenstand professionellen Handeln in der Erwachsenenbildung/Weiterbildung (EB/WB) einkreist und dabei sich der Perspektivverschränkung bedient, um das „Da-zwischen“ als Herausforderung bildungswissenschaftlicher Forschung zur Stabilisierung der Professionalität zu platzieren. Dazu bedarf es Detailanalysen unter bestimmten Forschungsfragestellungen. Besonders im Blick sind hierfür die Kompetenzfelder mit den jeweiligen Forschungsausrichtungen wie: Programm(planungs)forschung, Lehr- und Lernforschung, Organisationsforschung und Erforschung von Lernkulturen. Besondere Aufmerksamkeit für die Erwachsenenbildung/Weiterbildung verdient darüber hinaus die habituell einflussnehmenden Einwirkungen durch Bildungsbiographie und Lebensbedingungen, als auch die emotionalen Dispositionen die sich in den Erfahrungen, Lerninteressen und der Beziehungsfähigkeit des Individuums zu In-halten und Personen niederschlagen
First‐Principle Characterization of Structural, Electronic, and Optical Properties of Tin‐Halide Monomers
No full textThe growing interest in tin-halide semiconductors for photovoltaic applications demands in-depth knowledge of the fundamental properties of their constituents, starting from the smallest monomers entering the initial stages of formation. In this first-principles work based on time-dependent density-functional theory, we investigate the structural, electronic, and optical properties of tin-halide molecules SnXn2−n, with n = 1, 2, 3, 4 mathematical equation and X=Cl, Br, I, simulating these compounds in vacuo as well as in an implicit solvent. We find that structural properties are very sensitive to the halogen species while the charge distribution is also affected by stoichiometry. The ionicity of the Sn−X bond is confirmed by the Bader charge analysis albeit charge displacement plots point to more complex metal-halide coordination. Particular focus is posed on the neutral molecules SnX2, for which electronic and optical properties are discussed in detail. Band gaps and absorption onset decrease with increasing size of the halogen species, and despite general common features, each molecule displays peculiar optical signatures. Our results are elaborated in the context of experimental and theoretical literature, including the more widely studied lead-halide analogs, aiming to contribute with microscopic insight to a better understanding of tin-halide perovskites.Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347Niedersächsisches Ministerium für Wissenschaft und Kultur http://dx.doi.org/10.13039/501100010570Peer Reviewe
Amal Khaleefa (2023). Les langues au cœur de l’exil. Les Syriens du camp de Zaatari. Paris : Presse Sorbonne Nouvelle.
No full textErratum: In the review written by Nathalie Thamin on the work of Amal Khaleefa, /Les langues au cœur de l’exil. Les Syriens du camp de Zaatari/, the
date on page 129 stating “7 mars 2023” should be corrected to “7 octobre
2023”. The book was already online in 2023, but the official publication
date was 2024.
Dans la recension écrite par Nathalie Thamin de l’ouvrage d’Amal Khaleefa, /Les langues au cœur de l’exil. Les Syriens du camp de/
/Zaatari/, la date sur la page 129 indiquant le « 7 mars 2023 » doit
être remplacée par le « 7 octobre 2023 ». Le livre était déjà disponible
en ligne en 2023, mais sa date de publication officielle était 2024.Peer Reviewe
Characterization of Anticancer Drug Protomers Using Electrospray Ionization and Ion Mobility Spectrometry–Mass Spectrometry
No full textWe used electrospray ionization and ion mobility spectrometry–mass spectrometry to detect and characterize the three anticancer drugs palbociclib, copanlisib, and olaparib. Ion mobility–mass spectrometry and density functional theory revealed that these compounds generate isomers during ionization (protomers) due to the presence of multiple protonation sites within their chemical structures. Our work has implications for understanding the solution- and gas-phase chemistry of these molecules during spray-based ionization processes.Deutsche Forschungsgemeinschaft 10.13039/501100001659Bundesministerium f?r Bildung und Forschung 10.13039/501100002347Max-Planck-Gesellschaft 10.13039/501100004189Core Facility BioSupraMol NAPeer Reviewe
Музыка в лозунгах монстрации
No full textThe paper discusses the slogans of Monstration, a carnival manifestation that was held for the first time in Novosibirsk in 2004 and soon became an important social and cultural event in Russia. The posters of the participants reflect the current agenda of today's mass culture and some subcultures; therefore the research of the posters is important not only for the studies of the Monstration phenomenon but also the studies of modern culture. The paper focuses on the slogans that contain music references and, as a result, presents a general picture of musical tastes of the Monstration participants. Besides, the analysis of the music references allows us to propose a hypothesis about the role of music for today's youth.Статья посвящена слоганам Монстрации — карнавального шествия, впервые проведенного в 2004 году в Новосибирске и с тех пор ставшего важным социальным и культурным событием в России. Плакаты участников отражают повестку дня массовой культуры и некоторых субкультур и, таким образом, работа с этим материалом имеет значение не только для изучения самого феномена Монстрации, но также и современной культуры в целом. В фокусе внимания настоящего исследования находятся слоганы, содержащие разного рода отсылки к музыке и позволяющие воссоздать общую картину музыкальных вкусов монстрантов, а также выдвинуть предположение о роли, которую музыка играет в жизни молодых людей
Very high resolution aerial image orthomosaics, point clouds, and elevation datasets of select permafrost landscapes in Alaska and northwestern Canada
No full textPermafrost landscapes in the Arctic are highly vulnerable to warming, with rapid changes underway. High-resolution remote sensing, especially aerial datasets, offers valuable insights into current permafrost characteristics and thaw dynamics. Here, we present a new dataset of very high resolution orthomosaics, point clouds, and digital surface models that we acquired over permafrost landscapes in northwestern Canada and northern and northwestern Alaska for the purpose of better understanding the impacts of climate change on permafrost landscapes. The imagery was collected with the Modular Aerial Camera System (MACS) during aerial campaigns conducted by the Alfred Wegener Institute in the summers of 2018, 2019, and 2021. The MACS was specifically developed by the German Aerospace Center (DLR) for operation under challenging light conditions in polar environments. It features cameras in the optical and the near-infrared wavelengths with up to a 16 MP resolution. We processed the images to four-band (blue–green–red–near-infrared) orthomosaics and digital surface models with spatial resolutions of 7 to 20 cm as well as 3D point clouds with point densities of up to 41 points m −2 . The dataset collection features 102 subprojects from 35 target regions (1.4–161.1 km 2 in size). Project sizes range from 4.8 to 336 GB. In total, 3.17 TB were published. The horizontal precision of the datasets is in the range of 1–2 px and vertical precision is better than 0.10 m. The datasets are not radiometrically calibrated. Overall, these very high resolution images and point clouds provide significant opportunities for mapping permafrost landforms and generating detailed training datasets for machine learning, can serve as a baseline for change detection for thermokarst and thermo-erosion processes, and help with upscaling of field measurements to lower-resolution satellite observations. The dataset is available on the PANGAEA repository at 10.1594/PANGAEA.961577 .Peer Reviewe
[Sammelrezension] Yohann Aucante: The Swedish Experiment. The COVID-19 Response and its Controversies. Bristol: Bristol UP 2022, 184 S. ; Sigurd Bergmann, Martin Lindström (eds): Sweden’s Pandemic Experiment. London/New York: Routledge 2022, 332 S. ; SOU 2022:10: Sverige under pandemin. Volym 1: Samhällets, företagens och enskildas ekonomi. Stockholm: SOU 2022, 220 S. ; SOU 2022:10: Sverige under pandemin. Volym 2: Förutsättningar, vägval och utvärdering. Stockholm: SOU 2022, 758 S.
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