ALBERT

Description: Nach dem Streit um die Lieferung und den Besitz von Eisenstein zwischen Johannes, Abt des Klosters Grünhain, und Ernst II. von Schönburg, erließ Johannes mit Unterstützung von Kurfürst Johann Friedrich I. 1534 eine Bergordnung für den Eisensteinbergbau am Emmler und dem Hutstein.

Description: source

Description: Over the past two decades, the airborne Light Detection and Ranging (LiDAR) system has become a useful tool for acquiring high-resolution topographic data, especially in active tectonics studies. Analyzing Digital Terrain Models (DTMs) from LiDAR exposes morpho-structural elements, aiding in the understanding of fault zones, among other applications. Despite its effectiveness, challenges persist in regions with rapid deformation, dense vegetation, and human impact. We propose an adapted workflow transitioning from the conventional airborne LiDAR system to the usage of drone-based LiDAR technology for higher-resolution data acquisition. Additionally, drones offer a more cost-effective solution, both in an initial investment and ongoing operational expenses. Our goal is to demonstrate how drone-based LiDAR enhances the identification of active deformation features, particularly for earthquake-induced surface faulting. To evaluate the potential of our technique, we conducted a drone-based LiDAR survey in the Casamicciola Terme area, north of Ischia Island, Italy, known for the occurrence of destructive shallow earthquakes, including the 2017 Md = 4 event. We assessed the quality of our acquired DTM by comparing it with existing elevation datasets for the same area. We discuss the advantages and limitations of each DTM product in relation to our results, particularly when applied to fault mapping. By analyzing derivative DTM products, we identified the fault scarps within the Casamicciola Holocene Graben (CHG) and mapped its structural geometry in detail. The analysis of both linear and areal geomorphic features allowed us to identify the primary factors influencing the current morphological arrangement of the CHG area. Our detailed map depicts a nested graben formed by two main structures (the Maio and Sentinella faults) and minor internal faults (the Purgatorio and Nizzola faults). High-resolution DEMs acquired by drone-based LiDAR facilitated detailed studies of the geomorphology and fault activity. A similar approach can be applied in regions where the evidence of high slip-rate faults is difficult to identify due to vegetation cover and inaccessibility.

Description: Published

Description: 1899

Description: OST3 Vicino alla faglia

Description: JCR Journal

Description: More than forty years after the 23 November 1980 earthquake, which devastated the Campania and Basilicata regions, causing the destruction of a large number of towns and the death of around three thousand people, we have tried, through a large survey, to understand how and to what extent the urban fabric and the most affected communities have been rebuilt. Our main objective was to show, on one side, the commitment of the scientific community, and on the other the transitions that have led from the emergency to reconstruction. Of the Apenninic towns Conza della Campania, Laviano, Lioni, Santomenna, and others, where the devastation was almost total, we have tried to give an iconographic vision of the post-earthquake phase through the change in the urban layout. The partial or total reconstruction of the towns has taken place most of the time in situ, only in some cases by relocating buildings to neighboring areas, as happened in Conza della Campania, Bisaccia and Romagnano al Monte. Reconstruction was carried out mainly of anti-seismic buildings and only in some cases recovering preexisting buildings in historic centres; reconstruction was completed after a very long period, in some cases lasting over thirty years, inevitably passing through a dramatic experience of the population in temporary settlements of various kinds, from tents, caravans, railway carriages, to containers, and finally to thermo-igloos and to prefabricated wooden chalet-type. A very complex and detailed reconstruction was linked to factors not only territorial, economic and political but also conditioned unfortunately by the non-negligible intervention of organized crime.

Description: Published

Description: 103-130

Description: N/A or not JCR

Description: The twenty-eighth Conference of the Parties (COP28) to the United Nations Framework Convention on Climate Change (UNFCCC) in Dubai among many other items concluded the first Global Stocktake (GST) under the Paris Agreement. This article discusses the conference's outcomes in the areas of mitigation, loss and damage, adaptation, climate finance, and cooperation under Article 6 of the Paris Agreement. The conference arguably made history by for the first time ever recognising the need to "transition away" from fossil fuels, adopting specific targets for the scale-up of renewable energy and energy efficiency, and by operationalising a fund to support developing countries in dealing with loss and damage caused by climate change. However, the legal language in the call for an energy transition is relatively non-committal and the conference failed to underpin the new global objectives with adequate resources. Actual implementation of the Dubai outcomes will therefore to a large extent depend on whether COP29 in Baku, Azerbaijan - already billed as "finance COP" - will be able to cut the Gordian knot of finance.

Description: Aufgrund struktureller Haushaltsprobleme ist in vielen Gebietskörperschaften in den letzten Jahrzehnten im Bereich ihrer Liegenschaften ein immer größer werdender Sanierungsstau entstanden. Das heißt, notwendige Instandsetzungsinvestitionen, Modernisierungen und/oder energetische Sanierungen sind vielerorts unterblieben. Dieses Fachbuch zeigt innovative Lösungen auf.

Description: North Rhine-Westphalia (NRW) is the industrial center of Germany and one of the most important industrial locations in Europe. It is a key location for the energy-intensive basic materials industry like the production of steel and non-ferrous metals, (petro)chemicals, cement and lime, bricks, glass and ceramics, and paper. Around 20 % of NRW's total greenhouse emissions derive from industrial processes. By 2045, industry must achieve climate-neutrality, which requires a massive transformation effort. Technologically, this needs large-scale utilization of green hydrogen, carbon management, consequent circular economy, and climate-neutral production of process heat. Furthermore, various adjustments to the policy framework are essential.

Description: Digitalisierung und Nachhaltigkeit sind Megatrends der Gegenwart und der Zukunft. Die Digitalisierung bietet das Potenzial, das Nachhaltigkeitsmanagement von Unternehmen zu unterstützen. Die Nachhaltigkeitsplattform "EcoHub" erlaubt es, Unternehmensdaten mit Bezug zur Nachhaltigkeit an einer zentralen Stelle unter Berücksichtigung von Aspekten der Datensicherheit und Zugriffsberechtigung zu sammeln und als zentrale Datensenke der weiteren Analyse und für die Rückkopplung im Unternehmen zur Verfügung zu stellen.

Description: Over 175 million Nigerians rely on the use of traditional biomass for cooking, and it is estimated that more than 128,000 people died in Nigeria in 2019 from household air pollution related to these fuels. There is currently a gap in the study of possible pathways to meet Nigeria's goals in clean cooking and in understanding the health and climate impacts that different pathways can bring about. We explore clean cooking access scenarios for Nigeria until 2060 under a business-as-usual scenario, a moderate climate mitigation scenario, and an ambitious transformative scenario. We carry out a disaggregation at the state level for the period up to 2030 to better guide shorter-term policy development. Our analysis shows that under an ambitious scenario where 85 million households achieve access to clean cooking by 2060, annual premature deaths due to exposure to household air pollution would decrease by 7 % compared to 2018 levels. A baseline scenario, on the other hand, sees a dramatic 77 % increase, resulting in 209,000 people dying prematurely, of which 94,000 children under 5. Furthermore, we find that woodfuel removals from forestland would lead to a tripling of carbon dioxide emissions from land use change, reaching 602 Mt CO2 by 2060. Our findings stress the vital importance of a clean cooking transition in Nigeria and underline the urgent need for immediate acceleration in national efforts regarding access to clean cooking for all.

Description: Das zentrale Anliegen des Projektes besteht darin, regionale Stoffkreisläufe in der metallverarbeitenden Industrie zu schließen - mit einem Schwerpunkt auf (Hand-) Werkzeuge und Schneidwaren - sowie dies durch den Einsatz digitaler Technologien zu organisieren und zu optimieren. Das Ziel ist, Ressourcen- und Energieverbräuche zu reduzieren sowie ökonomische Vorteile für die Unternehmen zu realisieren. Im Detail soll es darum gehen, verschlissene metallische Produkte am End-of-Life nicht einer Verwertung durch Umschmelzen zuzuführen, sondern durch Remanufacturing und Repurposing die Nutzungsdauer der mit hohem Energie- und Ressourcenaufwand erzeugten Metalle zu verlängern. Diese Ansätze sollen unternehmensübergreifend aufgestellt werden und erfordern eine digital unterstützte Logistikkette sowie eine vollständige Rückverfolgbarkeit. Eine Rückführung verschlissener Maschinenmesser lohnt sich nach derzeitigem Kenntnisstand nicht, wenn dieses Material nur den Schrottpreis aufweist. Im Projekt "Circle of Tools" soll daher ein neues Geschäftsmodell entwickelt werden, das darauf basiert, sortenreine, qualitativ hochwertige Materialien entweder im primären Herstellungsprozess zu nutzen oder zur Weiterverarbeitung in andere Herstellungsprozesse unternehmensübergreifend zu integrieren. Neben den rein technischen Möglichkeiten werden betriebswirtschaftliche Faktoren, das Ressourceneffizienzpotenzial und der rechtliche Rahmen untersucht. Die in der europäischen Abfallrahmenrichtlinie und dem deutschen Kreislaufwirtschaftsgesetz verankerte Abfallhierarchie geht von der grundsätzlichen ökologischen Vorteilhaftigkeit der unterschiedlichen Stufen aus. Während das stoffliche Recycling von Produkten in der Regel vorteilhafter ist als ihre thermische Verwertung oder Deponierung, sind Reuse/Kaskadennutzung demnach ökologisch vorteilhafter als sämtliche Recyclingtechnologien. Die Datenlage ist hier jedoch im Vergleich zu vielen Recyclingtechnologien noch äußerst lückenhaft und unsystematisch. Einzelne Untersuchungen weisen jedoch auf signifikante Ressourceneffizienzpotenziale hin. Abschätzungen zeigen, dass die in diesem Vorhaben angedachte Reuse-/Kaskadennutzung zu einer Einsparung von 300 Tonnen Primär-Werkzeugstahl führen könnte. Das Vorhaben kann diese signifikanten Potenziale nachweisen und gleichzeitig geeignete und übertragbare Geschäftsmodelle aufzeigen. Auf Grundlage der empirischen Erhebungen werden im Projekt genaue Wirkungen berechnet für folgende Fragen: (1) Welche Mengen an Rohstoffe können durch Remanufacturing/Repurposing eingespart werden? (2) Welche ökonomische Wertschöpfung ist damit zu erzielen? (3) Wie ist ein Remanufacturing/Repurposing im Vergleich zu anderen Verwertungsverfahren ökologisch und ökonomisch einzuschätzen?

Description: The goal of this dissertation is to facilitate the assessment of impacts from sustainable measures and projects with an emphasis on impact reporting for Green, Social or Sustainability Bonds in the Sustainable Finance market. It does so by providing analysts with the means to develop, depict, formulate, and assess a causal hypothesis between an intervention and its subsequent effects in an impact-chain, represented by desired environmental (E), social (S) or governance (G) changes. This is achieved by developing a methodology for so-called ESG Logic Models or ESG-LM, that combine heuristic Theories-of-Change with propositional logic and Bayesian Reasoning. Three research questions are investigated and responded to. Research Question 1 asks how such Theories-of-Change can be developed for any type of ESG-related issue and how the different process steps in a causal chain can be classified, hierarchised, and prioritised regarding their efficacy towards overarching sustainability goals and their plausibility. Research Question 2 studies (a) the means by which the analyst or any other interested third party might be warranted in believing the causal claims from an ESG-LM, and (b) how an ESG-LM can be improved if this credence is low. Research Question 3 then looks at the reporting of impacts themselves regarding indicator selection, indicator assessment and indicator quantification as well as the provision of information on the contributions and attributions by different actors. The dissertation draws on a variety of theories and adapts existing methods to achieve that. It operationalises concepts from empirical Sustainable Finance research and already existing impact assessment methodologies. It adapts scholarly and practitioner approaches for theory-based evaluation and applies a qualitative social science perspective towards theory-building and evaluation, while some of the assessment tools in the dissertation are grounded in Logic, Set Theory and Bayesian Epistemology. Examples for such tools include rules for the Attribution by actors, heuristics for the abduction of plausible outcome pathways, or a four-stage Argument and Decision-Tree to assess the credibility of ESG-LM claims (based on Bayes Theorem). My assessment of the entire methodology is positive overall, as it provides solutions to each of the three research areas. Limitations of the approach, and thus opportunities for further research, are the additional expertise and time required by analysts compared to the existing, and somewhat more pragmatic, solutions in the current market. However, this is outweighed in my opinion by the ability of the framework to strongly mitigate impact washing by actors in the financial markets as well as biases by analysts. Its overall methodology also provides opportunities for new research angles in the area of sustainability indicators and assessments.

Description: This article investigates the event-triggered adaptive containment control problem for a class of stochastic nonlinear multiagent systems with unmeasurable states. A stochastic system with unknown heterogeneous dynamics is established to describe the agents in a random vibration environment. Besides, the uncertain nonlinear dynamics are approximated by radial basis function neural networks (NNs), and the unmeasured states are estimated by constructing the NN-based observer. In addition, the switching-threshold-based event-triggered control method is adopted with the hope of reducing communication consumption and balancing system performance and network constraints. Moreover, we develop the novel distributed containment controller by utilizing the adaptive backstepping control strategy and the dynamic surface control (DSC) approach such that the output of each follower converges to the convex hull spanned by multiple leaders, and all signals of the closed-loop system are cooperatively semi-globally uniformly ultimately bounded in mean square. Finally, we verify the efficiency of the proposed controller by the simulation examples.

Description: This paper presents a study on the predefined-time (PdT) and practical PdT synchronization of competitive neural networks (CNN) in the presence of different time scales and external disturbances. Two types of external disturbances, which satisfy Lipschitz or bounded conditions, are investigated respectively. The new PdT and practical PdT stability theorems are derived in singularly perturbed systems, where the final residual set is given in detail. By employing the newly derived stability theorems, novel autonomous controllers are designed without relying on a continuous linear term and time scale parameters, while enabling PdT or practical PdT synchronization for drive-response CNNs. Additionally, upper bounds for the settling time are estimated, allowing for adjusting the predefined synchronization times regardless of the initial conditions. Finally, numerical simulations are conducted to demonstrate the effectiveness of the main results.

Description: The evolution of the Antarctic Ice Sheet is of vital importance given the coastal and societal implications of ice loss, with a potential to raise sea level by up to 58 m if melted entirely. However, future ice-sheet trajectories remain highly uncertain. One of the main sources of uncertainty is related to nonlinear processes and feedbacks of the ice sheet with the Earth System on different timescales. Due to these feedbacks and the ice-sheet inertia, ice loss may already be triggered in the next decades and then unfolds delayed on multi-centennial to millennial timescales. This committed Antarctic sea-level contribution is not reflected in typical sea-level projections based on mass balance changes of Antarctica, which often cover decadal-to-centennial timescales. Here, using two ice-sheet models, we systematically assess the multi-millennial sea-level commitment from Antarctica in response to warming projected over the next centuries under low- and high-emission pathways. This allows bringing together the time horizon of stakeholder planning with the much longer response times of the Antarctic Ice Sheet. Our results show that warming levels representative of the lower-emission pathway SSP1-2.6 may already result in an Antarctic mass loss of up to 6 m sea-level equivalent on multi-millennial timescales. This committed mass loss is due to a strong grounding-line retreat in the Amundsen Sea Embayment as well as a potential drainage from the Ross Ice Shelf catchment and onset of ice loss in Wilkes subglacial basin. Beyond warming levels reached by the end of this century under the higher-emission trajectory SSP5-8.5, a collapse of the West Antarctic Ice Sheet is triggered in the entire ensemble of simulations from both ice-sheet models. Under enhanced warming, next to the marine parts, we also find a substantial decline in ice volume of regions grounded above sea level in East Antarctica. Over the next millennia, this gives rise to a sea-level increase of up to 40 m in our experiments, stressing the importance of including the committed Antarctic sea-level contribution in future projections.

Description: Detection of critical slowing down (CSD) is the dominant avenue for anticipating critical transitions from noisy time-series data. Most commonly, changes in variance and lag-1 autocorrelation [AC(1)] are used as CSD indicators. However, these indicators will only produce reliable results if the noise driving the system is white and stationary. In the more realistic case of time-correlated red noise, increasing (decreasing) the correlation of the noise will lead to spurious (masked) alarms for both variance and AC(1). Here, we propose two new methods that can discriminate true CSD from possible changes in the driving noise characteristics. We focus on estimating changes in the linear restoring rate based on Langevin-type dynamics driven by either white or red noise. We assess the capacity of our new estimators to anticipate critical transitions and show that they perform significantly better than other existing methods both for continuous-time and discrete-time models. In addition to conceptual models, we apply our methods to climate model simulations of the termination of the African Humid Period. The estimations rule out spurious signals stemming from nonstationary noise characteristics and reveal a destabilization of the African climate system as the dynamical mechanism underlying this archetype of abrupt climate change in the past.

Description: We show that many delay-based reservoir computers considered in the literature can be characterized by a universal master memory function (MMF). Once computed for two independent parameters, this function provides linear memory capacity for any delay-based single-variable reservoir with small inputs. Moreover, we propose an analytical description of the MMF that enables its efficient and fast computation. Our approach can be applied not only to single-variable delay-based reservoirs governed by known dynamical rules, such as the Mackey–Glass or Stuart–Landau-like systems, but also to reservoirs whose dynamical model is not available.

Description: Central Asia (CA) is among the world's most vulnerable regions to climate change. Increasing anthropogenic greenhouse gas concentrations (GHGs) are the primary forcing of the current and future climate system for the time scale of a century. By analysing observation datasets, we show that a warming of 1.2°C led to a decrease of 20% in snow-depth CA during the last 70 years, especially over the mountains. In recent decades, longer summer times and fewer icing days (more than 20 days·year−1) have exposed unprecedented shock to CA's climate system's components. Furthermore, we analyse 442 model simulations from Coupled Model Inter-comparison Project Phase 5 and 6 (CMIP5, CMIP6) and show that CMIP6 simulations are generally warmer and wetter than the CMIP5 ones in CA. For instance, under the highest emission scenarios (RCP8.5 and SSP5-8.5), CMIP6 projects a 6.1°C increase, while CMIP5 projects a 5.3°C increase, suggesting CMIP6 anticipates greater warming with high emissions. In contrast to CMIP6, the CMIP5 precipitation trends suggest a potential nonlinear relationship between increased greenhouse gas emissions and changes in precipitation, though the impact is much less pronounced than the temperature changes. Our analysis shows that CMIP6 models are more sensitive to temperature rise than CMIP5 ones. Both simulation sets' ensemble means capture well the observed warming trend. The imposed snow-melting leads to an increase in the run-off in the vicinity of glaciers. Such climatic shifts lead to more flooding events in CA. Given the projected warming range of 2–6°C in CA at the end of the century in various scenarios and models, such warming trends might be catastrophic in this region. The seasonal cycle of the temperature change indicates an extension of the glacier's melting period under future scenarios with fossil-fueled development. The models' uncertainty increases for the far-future time-slice, and warming larger than 4°C in CA is very likely among all the models and during all the seasons if no sustainable action is taken. This study also incorporates a detailed Köppen climate classification analysis, revealing significant shifts towards warmer climate categories in Central Asia, which may have profound implications for regional hydrological cycles and water resource management, particularly in the Amu Darya and Syr Darya river basins under warmer scenario by the end of the century. The Tundra and ice cap climate categories will lose more than 60% of their coverage at the end of the century compared to the historical period in the Amu Darya and Syr Darya river basins.

Description: Media inform the public, thereby influencing societal debates and political decisions. Despite climate change’s importance, drivers of media attention to climate change remain differently understood. Here we assess how different sociopolitical and extreme weather events affect climate change media coverage, both immediately and in the weeks following the event. To this end, we construct a data set of over 90,000 climate change articles published in nine major German newspapers over the past three decades and apply fixed effects panel regressions to control for confounders. We find that United Nations Climate Change Conferences affect coverage most strongly and most persistently. Climate protests incite climate coverage that extends well beyond the reporting on the event itself, whereas many articles on weather extremes do not mention climate change. The influence of all events has risen over time, increasing the media prominence of climate change.

Description: Understanding the ongoing investments in coal-fired power plants requires an analysis of the political economy. Here, we conduct a computational analysis of 212 interviews from 12 countries on the political economy of coal using topic modelling (TM). Our study highlights relevant topics by actor group and country. While most topics are similarly distributed across all actor groups, we find distinct clusters of countries in which similar topics play important roles. For example, in Indonesia and India, sustaining low electricity tariffs is brought forward as a reason to invest in coal, whereas in South Africa and Kenya the civil society is considered instrumental in the choice of coal or alternatives. To validate our findings, we compare them to outcomes of qualitative case studies and to papers grouping countries based on quantifiable factors. As this study is among the first to apply TM to interview data, we thereby highlight strengths and challenges for such application and the interpretability of results. We argue that topic models are effective supplements to qualitative case studies, particularly when analysing large amounts of text.

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: Seagrass meadows have a disproportionally high organic carbon (Corg) storage potential within their sediments and thus can play a role in climate change mitigation via their conservation and restoration. However, high spatial heterogeneity is observed in Corg, with wide differences seen globally, regionally, and even locally (within a seagrass meadow). Consequently, it is difficult to determine their contributions to the national remaining carbon dioxide (CO2) budget without introducing a large degree of uncertainty. To address this spatial heterogeneity, we sampled 20 locations across the German Baltic Sea to quantify Corg stocks and sources in Zostera marina seagrass-vegetated and adjacent unvegetated sediments. To predict and integrate the Corg inventory in space, we measured the physical (seawater depth, sediment grain size, current velocity at the seafloor, anthropogenic inputs) and biological (seagrass complexity) environments to determine regional and local drivers of Corg variation. Here, we show that seagrass meadows in Germany constitute a significant Corg stock, storing on average 7,785 g C/m2, 13 times greater than meadows from other parts of the Baltic Sea, and fourfold richer than adjacent unvegetated sediments. Stocks were highly heterogenous; they differed widely between (by 10-fold) and even within (by 3- to 55-fold) sites. Regionally, Corg was controlled by seagrass complexity, fine sediment fraction, and seawater depth. Autochthonous material contributed to 78% of the total Corg in seagrass-vegetated sediments, and the remaining 22% originated from allochthonous sources (phytoplankton and macroalgae). However, relic terrestrial peatland material, deposited approximately 6,000 years BP during the last deglaciation, was an unexpected and significant source of Corg. Collectively, German seagrasses in the Baltic Sea are preventing 8.14 Mt of future CO2 emissions. Because Corg is mostly produced on-site and not imported from outside the meadow boundaries, the richness of this pool may be contingent on seagrass habitat health. Disturbance of this Corg stock could act as a source of CO2 emissions. However, the high spatial heterogeneity warrants site-specific investigations to obtain accurate estimates of blue carbon and a need to consider millennial timescale deposits of Corg beneath seagrass meadows in Germany and potentially other parts of the southwestern Baltic Sea.

Description: Seit über einem halben Jahrhundert wissen wir um die erschreckenden Auswirkungen von Umweltzerstörung und Klimawandel. Zwar häufen sich internationale Umwelt- und Klimakonferenzen, doch warum handeln wir nicht konsequent gegen die verheerenden Bedrohungen? Mojib Latif wendet sich in diesem Buch der Frage zu, warum unsere Welt trotz besseren Wissens weiterhin auf gefährliche Weise den Ast absägt, auf dem sie sitzt. Latif stellt die unbequemen Fragen nach dem Versagen der Politik und den Interessen weniger mächtiger Konzerne, die von dieser fatalen Entwicklung profitieren. Die zentrale These dieses Buches ist ebenso klar wie dringlich: Der Klimawandel ist zum verhängnisvollen Verhandlungsobjekt geworden. Nur wenige dabei gewinnen – zahllose verlieren. Doch es gibt Hoffnung, und Latif zeigt den Weg: Die Zukunft nachfolgender Generationen kann gerettet werden, wenn wir uns auf globale Zusammenarbeit besinnen sowie Wohlstand und Nachhaltigkeit in Einklang bringen.

Description: Persistently high marine temperatures are escalating and threating marine biodiversity. The Baltic Sea, warming faster than other seas, is a good model to study the impact of increasing sea surface temperatures. Zostera marina, a key player in the Baltic ecosystem, faces susceptibility to disturbances, especially under chronic high temperatures. Despite the increasing number of studies on the impact of global warming on seagrasses, little attention has been paid to the role of the holobiont. Using an outdoor benthocosm to replicate near-natural conditions, this study explores the repercussions of persistent warming on the microbiome of Z. marina and its implications for holobiont function. Results show that both seasonal warming and chronic warming, impact Z. marina roots and sediment microbiome. Compared with roots, sediments demonstrate higher diversity and stability throughout the study, but temperature effects manifest earlier in both compartments, possibly linked to premature Z. marina die-offs under chronic warming. Shifts in microbial composition, such as an increase in organic matter-degrading and sulfur-related bacteria, accompany chronic warming. A higher ratio of sulfate-reducing bacteria compared to sulfide oxidizers was found in the warming treatment which may result in the collapse of the seagrasses, due to toxic levels of sulfide. Differentiating predicted pathways for warmest temperatures were related to sulfur and nitrogen cycles, suggest an increase of the microbial metabolism, and possible seagrass protection strategies through the production of isoprene. These structural and compositional variations in the associated microbiome offer early insights into the ecological status of seagrasses. Certain taxa/genes/pathways may serve as markers for specific stresses. Monitoring programs should integrate this aspect to identify early indicators of seagrass health. Understanding microbiome changes under stress is crucial for the use of potential probiotic taxa to mitigate climate change effects. Broader-scale examination of seagrass–microorganism interactions is needed to leverage knowledge on host–microbe interactions in seagrasses.

Description: We contend that ocean turbulent fluxes should be included in the list of Essential Ocean Variables (EOVs) created by the Global Ocean Observing System. This list aims to identify variables that are essential to observe to inform policy and maintain a healthy and resilient ocean. Diapycnal turbulent fluxes quantify the rates of exchange of tracers (such as temperature, salinity, density or nutrients, all of which are already EOVs) across a density layer. Measuring them is necessary to close the tracer concentration budgets of these quantities. Measuring turbulent fluxes of buoyancy (Jb), heat (Jq), salinity (JS) or any other tracer requires either synchronous microscale (a few centimeters) measurements of both the vector velocity and the scalar (e.g., temperature) to produce time series of the highly correlated perturbations of the two variables, or microscale measurements of turbulent dissipation rates of kinetic energy (ϵ) and of thermal/salinity/tracer variance (χ), from which fluxes can be derived. Unlike isopycnal turbulent fluxes, which are dominated by the mesoscale (tens of kilometers), microscale diapycnal fluxes cannot be derived as the product of existing EOVs, but rather require observations at the appropriate scales. The instrumentation, standardization of measurement practices, and data coordination of turbulence observations have advanced greatly in the past decade and are becoming increasingly robust. With more routine measurements, we can begin to unravel the relationships between physical mixing processes and ecosystem health. In addition to laying out the scientific relevance of the turbulent diapycnal fluxes, this review also compiles the current developments steering the community toward such routine measurements, strengthening the case for registering the turbulent diapycnal fluxes as an pilot Essential Ocean Variable.

Description: The 2015 Paris Agreement aims to strengthen the global response to climate change, and to maintain an average global temperature well below 2 °C, with aspirations towards 1.5 °C, by means of balancing sources and sinks of greenhouse gas emissions. Following this, the importance of carbon dioxide removal in global emission pathways has been further emphasized, and Negative Emissions Technologies (NETs) that capture carbon from the atmosphere and remove it from the system have been put in the spotlight. NETs range from innovative, engineered technologies, to well-known approaches like afforestation/reforestation. These technologies essentially compensate for a shrinking carbon budget coupled with hard-to-abate future emissions, and a historical lack of action. However, none has been deployed at scales close to what is envisioned in emission pathways in line with the Paris Agreement goals. To understand the potential contribution of NETs to meet global emission goals, we need to better understand opportunities and constraints for deploying NETs on a national level. We examine 17 Long-Term Low Greenhouse Gas Emission Development Strategies (LT-LEDS), and discuss them in the context of available NETs feasibility assessments. Our mapping shows that most countries include NETs in their long-term strategies, and that enhancement of natural sinks is the most dominating type of NET in these strategies. In line with many feasibility assessments, LT-LEDS focus on technical and biophysical considerations, and neglect socio-cultural dimensions. We suggest that feasibility assessments at the national level need to be more holistic; context-specific and comprehensive in terms of aspects assessed.

Description: Deep convection in the Subpolar Gyre (SPG) forms a link between the upper and lower limbs of the Atlantic Meridional Overturning Circulation (AMOC). The intensity of convection in ocean studies is usually estimated using mixed layer depth (MLD). Here MLD is derived using vertical profiles of potential density from the gridded ARMOR3D dataset and from in situ observations of the EN4 dataset. Given limited areas of convective chimneys, the robustness of the estimates from an available set of vertical profiles needs to be verified before accessing mechanisms of interannual variability of deep convection. For reaching this goal, we first outlined three convection domains in the SPG with a high frequency of deep convection events: the southwestern Labrador Sea (L-DC), the central Irminger Sea (I-DC), and the area south of Cape Farewell (F-DC). The minimum number of randomly scattered casts, required to be executed from January to April for a robust estimate of the maximum MLD, depends on the typical area of the convective regions within the domain and forms 50 casts for L-DC, 40 casts for I-DC and 10 casts for F-DC. For the investigated convection domains, a sufficient number of casts were collected for several standalone winters of the late 1990s, while continuous time series of the convection intensity can be obtained only since the mid-2000s.

Description: A novel strain, MA3_2.13T, was isolated from deep-sea sediment of Madeira Archipelago, Portugal, and characterized using a polyphasic approach. This strain produced dark brown soluble pigments, bronwish black substrate mycelia and an aerial mycelium with yellowish white spores, when grown on GYM 50SW agar. The main respiratory quinones were MK-10(H4), MK-10(H6) and MK-10(H8). Diphosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids and two glycophospholipids were identified as the main phospholipids. The major cellular fatty acids were iso-C16: 1, iso-C16: 0, anteiso-C17: 1 and anteisoC17: 0 . Phylogenetic analyses based on 16S rRNA gene showed that strain MA3_2.13T is a member of the genus Streptomyces and was most closely related to Streptomyces triticirhizae NEAU-YY642T (NR_180032.1; 16S rRNA gene similarity 97.9 %), Streptomyces sedi YIM 65188T (NR_044582.1; 16S rRNA gene similarity 97.4 %), Streptomyces mimosae 3MP-10T (NR_170412.1; 16S rRNA gene similarity 97.3 %) and Streptomyces zhaozhouensis NEAU-LZS-5T (NR_133874.1; 16S rRNA gene similarity 97.0 %). Genome pairwise comparisons with closest related type strains retrieved values below the threshold for species delineation suggesting that strain MA3_2.13T represents a new branch within the genus Streptomyces. Based on these results, strain MA3_2.13T (=DSM 115980T=LMG 33094T) is proposed as the type strain of a novel species of the genus Streptomyces, for which the name Streptomyces profundus sp. nov. is proposed.

Description: The recent severe European summer heat waves of 2015 and 2018 co-occurred with cold subpolar North Atlantic (NA) sea surface temperatures (SSTs). However, a significant connection between this oceanic state and European heat waves was not yet established. We performed two AMIP-like model experiments: (a) employing daily 2018 SSTs as observed and (b) applying a novel approach to remove the negative NA SST anomaly, while keeping SST daily and small-scale variability. Comparing these experiments, we find that cold subpolar NA SSTs significantly increase heat wave duration and magnitude downstream over the European continent. Surface temperature and circulation anomalies are connected by the upper-tropospheric summer wave pattern of meridional winds over the North Atlantic European sector, which is enhanced with cold NA SSTs. Our results highlight the relevance of the subpolar NA region for European summer conditions, a region that is marked by large biases in current coupled climate model simulations. Key Points: - Model study designed to investigate the ocean impact on European heat waves by prescribing observed and realistic ocean surface conditions - Cold subpolar North Atlantic sea surface temperatures significantly enhance heat wave intensity and duration over the European continent - North Atlantic ocean and European surface temperature and circulation anomalies are bridged by the upper-tropospheric summer mean wave

Description: The impact of oxygen on the preservation of organic matter in marine surface sediments is still controversial. We revisited this long-standing debate by determining the burial efficiency of sedimentary organic matter in the Black Sea, the largest anoxic and euxinic basin in the modern ocean. Surface sediments were sampled in the Danube paleodelta on the northwestern margin of the Black Sea at 420–1550 m water depth. Steady-state modeling of solid species (particulate organic carbon and nitrogen) and solutes (ammonium, sulfate, and total alkalinity) in sediments was performed to quantify rates of mass accumulation, particulate organic matter (POM) degradation, and POM burial. We develop a novel analytical model to quantify these rates applying an inverse modelling approach to down core data accounting for molecular diffusion, sediment burial and compaction. Our model results indicate that 56.7 ± 6.6 % of the particulate organic matter deposited in the study area is not degraded in surface sediments but accumulates below 10 cm sediment depth. This burial efficiency is substantially higher than those previously derived for seafloor areas underlying oxygenated bottom waters. Hence, our study confirms previous studies showing that euxinic bottom water conditions promote the preservation of particulate organic matter in marine sediments.

Description: The western Andean belt of Argentina displays a comprehensive record of the Carboniferous and earliest Permian rocks so extensive that it allows an exceptional reconstruction of the Late Paleozoic Ice Age of the southwestern margin of the South American Gondwana area. Severe endemism of the Gondwana biota during this period makes it difficult to achieve a precise correlation of these glacially influenced deposits with the coeval sequences of the palaeoequatorial belt, where the subdivisions of the International Chronostratigraphic Chart (ICC) are currently defined. The abundant palaeontological record available from the Upper Paleozoic deposits of central-western Argentina, central Patagonia and eastern Argentina makes it possible to recognize five successive faunal stages that allow a proper ordering of the sequences of this period. The proposed regional stages, and their assumed chronological position regarding the standards of the current ICC, are: the Malimanian (late Tournaisian), Barrealian (Mid-Carboniferous or Serpukhovian–Bashkirian), Aguanegrian (Upper Pennsylvanian), Uspallatian (Asselian–Tastubian?) and Bonetian (Sakmarian). This paper aims to reiterate former recommendations about the convenience of having regional reference units and suggests the consideration of the available faunal stages as possible chronostratigraphic subdivisions for the Carboniferous–early Permian of the southeastern margin of Gondwana.

Description: In its latest assessment report the IPCC stresses the need for carbon dioxide removal (CDR) to counterbalance residual emissions to achieve net zero carbon dioxide or greenhouse gas emissions. There are currently a wide variety of CDR measures available. Their potential and feasibility, however, depends on context specific conditions, as among others biophysical site characteristics, or availability of infrastructure and resources. In our study, we selected 13 CDR concepts which we present in the form of exemplary CDR units described in dedicated fact sheets. They cover technical CO2 removal (two concepts of direct air carbon capture), hybrid solutions (six bioenergy with carbon capture technologies) and five options for natural sink enhancement. Our estimates for their CO2 removal potentials in 2050 range from 0.06 to 30 million tons of CO2, depending on the option. Ten of the 13 CDR concepts provide technical removal potentials higher than 1 million tons of CO2 per year. To better understand the potential contribution of analyzed CDR options to reaching net-zero CO2 emissions, we compare our results with the current CO2 emissions and potential residual CO2 emissions in 2050 in Germany. To complement the necessary information on technology-based and hybrid options, we also provide an overview on possible solutions for CO2 storage for Germany. Taking biophysical conditions and infrastructure into account, northern Germany seems a preferable area for deployment of many concepts. However, for their successful implementation further socio-economic analysis, clear regulations, and policy incentives are necessary.

Description: In geoscience and other fields, researchers use models as a simplified representation of reality. The models include processes that often rely on uncertain parameters that reduce model performance in reflecting real-world processes. The problem is commonly addressed by adapting parameter values to reach a good match between model simulations and corresponding observations. Different optimization tools have been successfully applied to address this task of model calibration. However, seeking one best value for every single model parameter might not always be optimal. For example, if model equations integrate over multiple real-world processes which cannot be fully resolved, it might be preferable to consider associated model parameters as random parameters. In this paper, a random parameter is drawn from a wide probability distribution for every singe model simulation. We developed an optimization approach that allows us to declare certain parameters random while optimizing those that are assumed to take fixed values. We designed a corresponding variant of the well known Covariance Matrix Adaption Evolution Strategy (CMA-ES). The new algorithm was applied to a global biogeochemical circulation model to quantify the impact of zooplankton mortality on the underlying biogeochemistry. Compared to the deterministic CMA-ES, our new method converges to a solution that better suits the credible range of the corresponding random parameter with less computational effort.

Description: Sea spray aerosols (SSA) greatly affect the climate system by scattering solar radiation and acting as seeds for cloud droplet formation. The ecosystems in the Arctic Ocean are rapidly changing due to global warming, and the effects these changes have on the generation of SSA, and thereby clouds and fog formation in this region, are unknown. During the ship-based Arctic Century Expedition, we examined the dependency of forced SSA production on the biogeochemical characteristics of seawater using an on-board temperature-controlled aerosol generation chamber with a plunging jet system. Our results indicate that mainly seawater salinity and organic content influence the production and size distribution of SSA. However, we observed a 2-fold higher SSA production from waters with similar salinity collected north of 81°N compared to samples collected south of this latitude. This variability was not explained by phytoplankton and bacterial abundances or Chlorophyll-a concentration but by the presence of glucose in seawater. The synergic action of sea salt (essential component) and glucose or glucose-rich saccharides (enhancer) accounts for 〉80% of SSA predictability throughout the cruise. Our results suggest that besides wind speed and salinity, SSA production in Arctic waters is also affected by specific organics released by the microbiota.

Description: The University of Victoria Earth system climate model of intermediate complexity has been a useful tool in recent assessments of long-term climate changes including paleo-climate modelling. Since the last official release of the UVic ESCM 2.9, and the two official updates during the last decade, a lot of model development has taken place in multiple groups. The new version 2.10 of the University of Victoria Earth System Climate Model (UVic ESCM), to be used in the 6th phase of the coupled model intercomparison project (CMIP6), presented here combines and brings together multiple model developments and new components that have taken place since the last official release of the model. To set the foundation of its use, we here describe the UVic ESCM 2.10 and evaluate results from transient historical simulations against observational data. We find that the UVic ESCM 2.10 is capable of reproducing well changes in historical temperature and carbon fluxes, as well as the spatial distribution of many ocean tracers, including temperature, salinity, phosphate and nitrate. This is connected to a good representation of ocean physical properties. For the moment, there remain biases in ocean alkalinity and dissolved inorganic carbon, which will be addressed in the next updates to the model.

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: Following several small-scale benthic disturbance experiments, an industrial polymetallic nodule collector trial was conducted by the company Global Sea mineral Resources (GSR) in their exploration contract area in the Clarion-Clipperton Zone using the pre-prototype vehicle Patania II (PATII). In this study, meiofaunal (i.e., nematode abundance, ASV diversity and genus composition) and environmental (i.e., grain size, total organic carbon/total nitrogen and pigment) properties are compared between disturbance categories (i.e., Pre-impact, Collector Impact and Plume Impact). One week after the trial, proxies for food availability within the Collector Impact sediments were altered with lower total organic carbon (TOC) and pigment (i.e., CPE: sum of Chlorophyll a and phaeopigments) values. Albeit not significant, the observed decrease of nematode abundance and ASV diversity, further indicate the consequences of the removal of the ecologically important surface sediment layer within the PATII tracks. Next to sediment removal, exposed sediments were modified in different ways (e.g., central strips, parallel caterpillar imprints with alternating bands of depressions/ripples and interface patches) and were also subject to heavy collector-induced sediment blanketing. We propose that these cumulative impacts have led to intricate seabed modifications with various levels of disturbance intensity which resulted in the high meiofaunal variability observed. Adjacent nodule-rich areas (i.e., Plume Impact) received considerable levels of sediment deposition (2-3 cm) and were defined by significantly lower food sources (CPE, TOC, carbon to nitrogen ratio) and an observation of meiofaunal enrichment (i.e., higher average nematode abundance and ASV diversity; although statistically non-significant), but mechanisms behind these ecological changes (e.g., suspended material-surface fluxes, passive dispersal of fauna in the plume vs. active upward migration and “viability” of redeposited fauna) remain unresolved. We conclude that complex benthic pressure-response relationships associated with the PATII trial, combined with the high degree of natural spatial and temporal variability in abyssal meiofaunal communities and sedimentary parameters, complicates the quantitative assessment of deep-sea mining associated disturbances.

Description: Flow of dense shelf water provide an efficient mechanism for pumping CO 2 to the deep ocean along the continental shelf slope, particularly around the Antarctic bottom water (AABW) formation areas where much of the global bottom water is formed. However, the contribution of the formation of AABW to sequestering anthropogenic carbon ( C ant ) and its consequences remain unclear. Here, we show prominent transport of C ant (25.0 ± 4.7 Tg C yr −1 ) into the deep ocean (〉2,000 m) in four AABW formation regions around Antarctica based on an integrated observational data set (1974–2018). This maintains a lower C ant in the upper waters than that of other open oceans to sustain a stronger CO 2 uptake capacity (16.9 ± 3.8 Tg C yr −1 ). Nevertheless, the accumulation of C ant can further trigger acidification of AABW at a rate of −0.0006 ± 0.0001 pH unit yr −1 . Our findings elucidate the prominent role of AABW in controlling the Southern Ocean carbon uptake and storage to mitigate climate change, whereas its side effects (e.g., acidification) could also spread to other ocean basins via the global ocean conveyor belt. Plain Language Summary The Southern Ocean is thought to uptake and store a large amount of anthropogenic CO 2 ( C ant ), but little attention has been paid to the Antarctic coastal regions in the south of 60°S, mainly due to the lack of observations. Based on an integrated data set, we discovered the deep penetration of C ant and a visible pattern of relatively high concentration of C ant along the AABW formation pathway, and the concentration of C ant along the shelf‐slope is higher than that of other marginal seas at low‐mid latitudes, implying a highly effective C ant transport in AABW formation areas. We also found strong upper‐layer CO 2 uptake and a significant acidification rate in the deep waters of the Southern Ocean due to the AABW‐driven CO 2 transport, which is 3 times faster than those in other deep oceans. It is therefore crucial to understand how the Antarctic shelf regions affect the global carbon cycle through the uptake and transport of anthropogenic CO 2 , which also drives acidification in the other ocean basins. Key Points We show evidence for the accumulation of C ant along the Antarctic shelf‐slope into the deep ocean The process of AABW formation drives C ant downward transport at 25.0 ± 4.7 Tg C yr −1 , sustaining the CO 2 uptake in the surface ocean This further triggers acidification of AABW at a rate of −0.0006 ± 0.0001 pH unit yr −1 , which is faster than in other deep oceans

Description: The ocean region along the latitude of 40oS in the South Atlantic, characterized by enhanced primary productivity, forms a transition zone between the nutrient replete but iron depleted Southern Ocean, and the nitrate and iron depleted Subtropical Gyre. Here, we present distributions of nutrient-type dissolved and particulate trace metals (dTMs and pTMs) including cadmium (Cd), nickel (Ni), copper (Cu), and zinc (Zn) in the South Atlantic from the GEOTRACES GA10 cruises. Phytoplankton uptake, riverine and atmospheric inputs shaped dTM and pTM concentrations in surface waters (dCd 27.8±36.0 pmol kg-1, n=222; dCu 0.732±0.429 nmol kg-1, n=222; dNi 3.38±0.52 nmol kg-1, n=219; dZn 0.332±0.398 nmol kg-1, n=214). Subsurface nutrients and dTMs (dCd 563±184 pmol kg-1, n=335; dCu 1.819±0.773 nmol kg-1, n=334; dNi 6.19±1.06 nmol kg-1, n=330; dZn 3.71±2.10 nmol kg-1, n=333) were controlled by the mixing of Antarctic origin waters and North Atlantic Deep Waters (NADW) with negligible contributions from local remineralization. Dissolved and particulate TMs in the Argentine Basin showed elevated concentrations towards the seafloor because of benthic inputs. Direct hydrothermal inputs of dTMs and pTMs to deep waters were not observed along the transect. The Cd-Cu-Zn-phosphate stoichiometries of Antarctic origin waters were set by a combination of dynamic physical circulation and preferential uptake of Cd, Cu, and Zn relative to phosphate in surface waters because of a dominance by diatoms in the Southern Ocean. Water mass mixing subsequently produced convoluted dCu-P and dZn-P relationships and apparent linear dCd-P and dNi-P relationships in the South Atlantic. More importantly, endmember characteristics of Antarctic waters and NADW are largely fixed in their formation regions in high latitude oceans. Therefore, the highly dynamic high latitude oceans are key regions that supply nutrients and TMs at specific ratios to low latitude oceans via the thermohaline circulation. Changes to processes in the high latitude oceans may have consequences for marine primary productivity downstream, and hence the global carbon cycle.

Description: To reach their net-zero targets, countries will have to compensate hard-to-abate CO2 emissions through carbon dioxide removal (CDR). Yet, current assessments rarely include socio-cultural or institutional aspects or fail to contextualize CDR options for implementation. Here we present a context-specific feasibility assessment of CDR options for the example of Germany. We assess 14 CDR options, including three chemical carbon capture options, six options for bioenergy combined with carbon capture and storage (BECCS), and five options that aim to increase ecosystem carbon uptake. The assessment addresses technological, economic, environmental, institutional, social-cultural and systemic considerations using a traffic-light system to evaluate implementation opportunities and hurdles. We find that in Germany CDR options like cover crops or seagrass restoration currently face comparably low implementation hurdles in terms of technological, economic, or environmental feasibility and low institutional or social opposition but show comparably small CO2 removal potentials. In contrast, some BECCS options that show high CDR potentials face significant techno-economic, societal and institutional hurdles when it comes to the geological storage of CO2. While a combination of CDR options is likely required to meet the net-zero target in Germany, the current climate protection law includes a limited set of options. Our analysis aims to provide comprehensive information on CDR hurdles and possibilities for Germany for use in further research on CDR options, climate, and energy scenario development, as well as an effective decision support basis for various actors. Key Points: - More context-specific assessments of carbon dioxide removal (CDR) options are needed to guide national net-zero decision making - Ecosystem-based CDR options with comparably low implementation hurdles in Germany show relatively small CO2 removal potentials - High CDR potential options in Germany face high institutional, technological and societal hurdles linked in many ways to geological storage

Description: The data set contains measurements performed by the passive radiometer Humidity And Temperature PROfiler (HATPRO; Rose et al., 2005) operated on board the Polar 5 research aircraft during 13 flights of the HALO-AC3 airborne campaign, carried out in early spring 2022 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of brightness temperature measurements at the nadir view with respect to the aircraft's fuselage at seven frequencies in the 22.24 GHz water vapor absorption band and seven at the 60 GHz oxygen absorption complex. It should be considered that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality-checked and is available separately in NetCDF format for each flight.

Description: The published data set consists of measurements performed by the active cloud radar as part of the Microwave Radar and radiometer for Arctic Clouds (MiRAC; Mech et al., 2019) operated on board the Polar 5 research aircraft during 11 flights of the HALO-AC3 airborne campaign, carried out in early spring 2022 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of radar reflectivities of the FMCW 94 GHz cloud radar transformed to nadir view and brightness temperature measurements at 89 GHz with a 25 deg backward inclination with respect to the aircraft's fuselage. It should be considered that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality-checked and is available in NetCDF format for each flight separately. Details on the instrument can be found in Mech et al. (2019).

Description: The data set contains measurements performed by the passive radiometer Humidity And Temperature PROfiler (HATPRO; Rose et al., 2005) operated on board the Polar 5 research aircraft during 9 flights of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Airborne observations in the Central Arctic (MOSAiC-ACA; Mech et al., 2022) campaign, carried out in late summer 2020 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of brightness temperature measurements at nadir view with respect to the aircraft's fuselage at seven frequencies in the 22.24 GHz water vapor absorption band and seven at the 60 GHz oxygen absorption complex. It should be considered that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality-checked and is available in NetCDF format for each flight separately. Details on the dataset and its usage can be found in Mech et al. (2022).

Description: The data set contains the cloud mask and cloud top altitude derived from measurements with the Airborne Mobile Aerosol Lidar (AMALi; Stachlewska et al., 2010) operated on board the Polar 5 research aircraft during 11 flights of the HALO-AC3 airborne campaign carried out in early spring 2022 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. It should be considered that the measurements have not been corrected for aircraft attitude. The data set has been quality-checked and is available in NetCDF format for each flight separately.

Description: The published data set consists of measurements performed by the active cloud radar as part of the Microwave Radar and radiometer for Arctic Clouds (MiRAC; Mech et al., 2019) operated on board the Polar 5 research aircraft during 7 flights of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Airborne observations in the Central Arctic (MOSAiC-ACA; Mech et al., 2022) campaign, carried out in late summer 2020 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of radar reflectivities of the FMCW 94 GHz cloud radar transformed to nadir view as well as brightness temperature measurements at 89 GHz with a 25 deg backward inclination with respect to the aircraft's fuselage. It should be considered that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality-checked and is available in NetCDF format for each flight separately. Details on the instrument can be found in Mech et al. (2019) and on the dataset and its usage in Mech et al. (2022).

Description: The data set contains measurements performed by the passive radiometer as part of the Microwave Radar and radiometer for Arctic Clouds (MiRAC; Mech et al., 2019) operated on board the Polar 5 research aircraft during 14 flights of the Airborne measurements of radiative and turbulent FLUXes of energy and momentum in the Arctic boundary layer (AFLUX; Mech et al., 2022) campaign, carried out in spring 2019 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of brightness temperature measurements at nadir view with respect to the aircraft's fuselage at six frequencies in the water vapor absorption band at around 183.31 GHz and at two additional channels at 243 and 340 GHz. It should be considered that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality-checked and is available in NetCDF format for each flight separately. Details on the instrument can be found in Mech et al. (2019) and on the dataset and its usage in Mech et al. (2022).

Description: During the HALO-(AC)3 campaign, the hyperspectral and polarized imaging system specMACS was integrated into the German research aircraft HALO. This dataset contains videos with measurements of the two polarization resolving cameras of specMACS which measure the two-dimensional distribution of the I, Q, and U components of the Stokes vector at red, green, and blue color channels with an acquisition rate of 8Hz. Both cameras are operated in a nadir looking perspective and have a combined field of view of 91 x 117 degree in along and across track direction. The videos include RGB images as well as images of the degree of linear polarization derived from the measurements.

Description: The published data set consists of measurements performed by the active cloud radar as part of the Microwave Radar and radiometer for Arctic Clouds (MiRAC; Mech et al., 2019) operated on board the Polar 5 research aircraft during 14 flights of the Airborne measurements of radiative and turbulent FLUXes of energy and momentum in the Arctic boundary layer (AFLUX) campaign, carried out in spring 2019 northwest of Svalbard (Norway). The measurement campaign is embedded in the Transregional Collaborative Research Centre TR 172 (ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3. The published data set consists of radar reflectivities of the FMCW 94 GHz cloud radar transformed to nadir view as well as brightness temperature measurements at 89 GHz with a 25 deg backward inclination with respect to the aircraft's fuselage. It should be considered that the brightness temperatures have not been corrected for aircraft attitude. The data set has been quality-checked and is available in NetCDF format for each flight separately. Details on the instrument can be found in Mech et al. (2019) and on the dataset and its usage in Mech et al. (2022)

Description: This data set is composed of in-situ measurement of arctic cloud microphysical properties (particle size distribution and volumic cloud particle scattering properties) observed during the HALO-AC3 campaign, which occurred between March 20th and April 10th 2022. These measurements were made using the 2D stereoscopic (2D-S, SPEC Inc.) and Polar Nephelometer (Gayet et al., 1997) probes from the airborne measurement platform of the Laboratoire de Météorologie Physique (CNRS/UCA, Aubière, France). There is one file per flight. All files are in NetCDF format, with a complete description of the parameters inside. A detailed list of the parameters present in the data set is added in a separate document (see "Further details" link).

Description: During the HALO-(AC)3 campaign, the hyperspectral and polarized imaging system specMACS was integrated into the German research aircraft HALO in a nadir-looking perspective. This dataset contains calibrated spectral radiances in mW/(m2 nm sr) for the shortwave infrared wavelength range between about 1000 and 2400nm measured by the SWIR spectrometer of specMACS. The spectrometer has 320 spatial pixels along a spatial line oriented in across-track direction with a field of view of 35.5 degree and measures at an acquisition frequency of 30Hz. The calibration of the data was performed as described in Ewald et al. (2016). Because of the large size of the data, the calibrated radiances for each research flight were split into different files along the wavelength dimension. Each dataset contains measurements of 20 wavelength channels for the wavelength range given in the file name. Additionally, the dataset includes georeferencing information with viewing zenith and viewing azimuth angles as well as sensor latitude, longitude, and height above WGS84 for every measured pixel as a separate file for every flight. Note that during the first three flights there was some icing of the window in front of the cameras which is visible in the data.

Description: During the HALO-(AC)³ campaign in March and April 2022 downward looking lidar profiles were measured onboard of the High Altitude LOng range research aircraft (HALO) over the Arctic sea ice and ocean using the airborne demonstrator for the WAter vapour Lidar Experiment in Space (WALES). The data set gives time series of profiles of backscatter ratio, particle depolarization and water vapour molecular density measured along the flight path of HALO on 17 days. All flights started from Kiruna, Sweden and headed into the Fram Straight and towards the central Arctic. The goal of the campaign was to study warm air intrusions and cold air outbreaks to and from the Arctic and to follow those air masses over several days with remote sensing instrumentation aboard HALO. The first research flight (RF) was RF02. RF01 was the transfer flight from Oberpfaffenhofen, Germany to Kiruna. Backscatter ratio and aerosol depolarization data is given with at one second time resolution and 15 m vertical binning at a wavelength of 532 nm. The backscatter profiles are extinction corrected using the High Spectral Resolution Lidar (HSRL) method. The water vapour profiles have a time resolution of 12 s and a vertical binning of 15 m. For H2O the vertical resolution is lower than given by the binning, where the real resolution is determined by an averaging kernel which is constant over height and has a full width at half maximum (FWHM) of 250 m. All data is regridded to a constant altitude scale over mean sea level, irrespective of the actual flight altitude.

Description: One of the main goals of the HALO-(AC)3 Arctic airborne campaign conducted in spring 2022 was a quasi-Lagrangian sampling of air masses. This means that the same air masses were to be sampled twice. Such a measurement strategy allows for concrete observations of air mass transformations, which can for example be used to benchmark weather models. After finishing the campaign, trajectory calculations were conducted for all flights of the HALO aircraft to check whether the flight strategy was a success. For this, the trajectory calculation tool Lagranto was used in conjunction with wind fields from the ERA5 reanalysis. Latter has an output resolution of around 30 km and one hour. The hourly data was bi-linearly interpolated to one minute resolution. Air masses were initialized temporally every one minute along the flight track of HALO, and vertically every 5 hPa between 250 hPa and 10 hPa above the ground level. Horizontally, air masses were started within a 30 km radius circle centered around the location of HALO. In each circle, 30 air masses were initialized evenly spaced approximately every 10 km, allowing for a better statistical analysis. Trajectories were then calculated in one-minute steps up to 10 hours forward in time. At typical HALO flight times of up to 10 hours, around 2.7 million trajectories were calculated per research flight. A quasi-Lagrangian match is registered if the same air mass is seen again below HALO at a later time of the same day and within the same 30 km radius. In order to allow air masses to evolve, a minimum temporal threshold of one hour was applied between matches.

Description: TRIAXUS is a towed and undulating system which was equipped with a SEABIRD FASTCAT, SBE 49, AANDERAA OXYGEN OPTODE 4330 F, and a SEASCAN SUNADeep Nitrate Sensor. It measured: seawater temperatures, salinity, dissolved oxygen and nitrate concentrations in the water column.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (in review). The data processing is described in Pilz et al. (in preparation). The present dataset covers the solar irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020.

Description: The Mini Dot Oxygen Sensor (MDO) was attached to a mooring and recorded seawater temperatures and dissolved oxygen concentrations.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: In the framework of the Multidisciplinary Observatory for the Study of Arctic Climate (MOSAiC) expedition, the tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was deployed from a research camp on an ice floe drifting in the Fram Strait in Summer 2020. The BELUGA system consists of a 90 m³ helium-filled balloon with modular instrumentation. Lonardi et al. 2021 (submitted to Elementa) gives an overview of the BELUGA observations during MOSAiC leg 4. Pilz et al. (in preparation) describe the BELUGA operations and data processing routines. The present data set covers the aerosol particle measurements with the Cubic Aerosol Measurement Platform (CAMP) (details in Pilz et al. in preparation) on 18 flights with mean altitudes of 1 km between 29 June and 27 July 2020.

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (submitted). The data processing is described in Pilz et al. (in preparation). The present dataset covers the processed terrestrial irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Terrestrial irradiances were corrected for the time response of the pyrgeometer (6 s) and averaged over 3 s. Flagging of ice and liquid water is provided, based on the analysis of 0.1 Hz pictures of the upper pyrgeometer. Solar irradiances are also available (doi:10.1594/PANGAEA.944232).

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (submitted). The data processing is described in Pilz et al. (in preparation). The present dataset covers the processed terrestrial irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Terrestrial irradiances were corrected for the time response of the pyrgeometer (6 s) and averaged over 3 s. Flagging of ice and liquid water is provided, based on the analysis of 0.1 Hz pictures of the upper pyrgeometer. Solar irradiances are also available (doi:10.1594/PANGAEA.944232).

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (submitted). The data processing is described in Pilz et al. (in preparation). The present dataset covers the processed terrestrial irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Terrestrial irradiances were corrected for the time response of the pyrgeometer (6 s) and averaged over 3 s. Flagging of ice and liquid water is provided, based on the analysis of 0.1 Hz pictures of the upper pyrgeometer. Solar irradiances are also available (doi:10.1594/PANGAEA.944232).

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (submitted). The data processing is described in Pilz et al. (in preparation). The present dataset covers the processed terrestrial irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Terrestrial irradiances were corrected for the time response of the pyrgeometer (6 s) and averaged over 3 s. Flagging of ice and liquid water is provided, based on the analysis of 0.1 Hz pictures of the upper pyrgeometer. Solar irradiances are also available (doi:10.1594/PANGAEA.944232).

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (submitted). The data processing is described in Pilz et al. (in preparation). The present dataset covers the processed terrestrial irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Terrestrial irradiances were corrected for the time response of the pyrgeometer (6 s) and averaged over 3 s. Flagging of ice and liquid water is provided, based on the analysis of 0.1 Hz pictures of the upper pyrgeometer. Solar irradiances are also available (doi:10.1594/PANGAEA.944232).

Description: The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (in review). The data processing is described in Pilz et al. (in preparation). The present dataset covers the solar irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020.