bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated classification of the German soil map (BUEK 200) into FOOTPRINT soil types and its parameterization for hydrological modelling
Authors: Reichenberger Stefan , Pohlert Thorsten , He Qianwen , Gebler Sebastian , Multsch Sebastian , Erzgraeber Beate
Published: February 2023

The FOOTPRINT Soil Type (FST) system has been derived during the FOOTPRINT project (2006-2009) to facilitate spatially distributed hydrological and solute transport modelling at national or EU scale. The basic idea of this approach is to classify the soil typological units (STUs) of a national or European soil database into a limited number of soil types (FSTs) in order to reduce the number of unique soil-climate combinations for the later numerically expensive simulations. The FST code consists of a hydrological class (the FOOTPRINT Hydrologic Group), a topsoil and a subsoil texture code and an organic matter profile code. The FST system is model-independent, but complete parameterization methodologies were established during FOOTPRINT for MACRO, a 1-D dual permeability model for simulating water flow and solute transport in macroporous soils at field level. In this study we i) translated the latest version of the German soil map 1:200,000 (BUEK200) into FSTs, ii) derived representative profiles for all FSTs with arable land use, and iii) parameterized these representative profiles in MACRO. The 3648 STUs with arable land use in the BUEK200 were classified into 226 FSTs. Area proportions covered by the different FSTs are highly skewed: The 13 FSTs with the largest areas already cover 50 % of the total arable land. The hydrological class of each FST indicates whether artificial drainage is needed to allow arable landuse, and a map of potentially drained arable land was derived for Germany accordingly. A representative soil profile was established for every FST by depth-based averaging over all soil profiles belonging to the same FST. Special care had to be taken to ensure that mineral soil layers were not mixed with peat or hard rock layers. The plausibility of the representative FST profiles and their MACRO parameterization was checked with water balance simulations. The present case study for the BUEK200 soil database demonstrates the potential of the FST system for spatially distributed hydrological and solute transport modelling at large scale based on national soil databases.
Loops of slack in dark fiber and their effect on interferometric analysis of ambient noise – symptoms, consequences and remedies
Authors: Wollin Christopher , Ehsaninezhad Leila , Hart Johannes , Lipus Martin , Krawczyk Charlotte
Published: February 2023

Seismic microzonation and ambient noise tomography via Distributed Acoustic Sensing (DAS) may contribute to the seismic hazard assessment and the exploration or monitoring of utilizable and utilised subsurface volumes at favorable costs. However, numerous technical aspects remain under investigation to further maturate this innovative seismological approach – particularly when applied to dark telecommunication fibers. For instance unknown coupling of the fiber to the ground or presence of loops of slack fiber may disturb the regular measuring of the stringed virtual sensors. In this study, we investigate how loops of slack fiber affect the results of passive ambient tomography, a particularly appealing exploration approach due to its low footprint. We present results obtained with DAS recordings on purposefully installed as well as dark telecommunication optic fiber. Sledgehammer blows were recorded on an optic fiber laid out in an urban heating tunnel before and after introducing several loops of slack. The loops coiled up fractions and multiples of the utilized gauge length and were spaced in sufficient distance to independently analyze the surrounding wavefield. Discontinuous wavefronts can be observed once the coiled fiber exceeds the gauge length. Similar observations were made on the virtual shot gathers calculated along a 4.5 km long segment of dark fiber along a major road in the city of Berlin, Germany. We show how the loops of slack affect the further processing with respect to ambient noise tomography. On average, the removal of virtual sensors identified to be located in coiled fiber reduces the shear-wave velocities in the resulting model. We conclude that the careful removal of virtual sensors within loops of slack is a mandatory processing step towards ambient noise tomography with linear DAS arrays. However, the calculation of virtual shot gathers can help to reveal the affected fiber segments.
ABRUPT Arctic Climate Change
Authors: Risebrobakken Bjørg , Wang Yunyi , Guo Chuncheng , Blindheim Dag Inge , Dokken Trond , Fahl Kirsten , Jansen Eystein , Klockmann Marlene , Tessier Juliette , Tisserand Amandine , Stein Rüdiger , Vetteretti Guido , Witkowski Andrzej
Published: February 2023

At unprecedented resolution we investigate the nature of Dansgaard-Oeschger events in the Fram Strait, the gateway between the Nordic Seas and the Arctic Ocean. The new reconstructions of biomarkers and sea ice variability, stable isotopes and IRD will be seen in context of sea ice conditions, ocean hydrography and climate of the Nordic Seas as seen in multi-model output from three transient glacial GCM simulations (NorESM, CESM, MPI-ESM) and high-resolution reconstructions from an eastern Nordic Seas transect (from the Faeroe-Shetland Channel, via the Norwegian Sea to the Fram Strait). The combined results show that ocean-atmosphere-sea ice processes and dynamics during the transition from H4 to GI8 are strongly coupled.  Both model results and reconstructions suggest subsurface ocean warming and polynya events in the southern- and northernmost Nordic Seas during the cold stadial. For a short time during the stadial to interstadial transition, a corridor of open water and hence sea ice-free conditions existed from the southern Nordic Seas all the way to the Fram Strait. The breakup of the sea ice cover is likely caused by the overshoot of AMOC during the transition and the associated enhanced ocean heat transport into the Nordic Seas. After the transition, winter sea ice grows back in the Fram Strait during the interstadial state, but the Southern Nordic Seas remain ice-free.
Analysis of Ensemble Uncertainty Transfer in AI-Based Downscaling of C3S Seasonal Forecast
Authors: Lin Qing , Heidari Fatemeh , Espitia Sarmiento Edgar Fabián , Adakudlu Muralidhar , Toreti Andrea , Xoplaki Elena
Published: February 2023

Copernicus Climate Change Service (C3S) integrates multiple seasonal forecast models of climate variables with multiple ensemble realizations. Assessing the risks of natural hazards with high impacts on human and natural systems and providing actionable services at the local scale require high-resolution predictions. We implement the AI-based approach proposed by Heidari et al. (2023) to address such needs and reach a kilometer scale. While downscaling seasonal forecasts, it is crucial to transfer the full range of the uncertainties given by the ensembles.This study assesses how uncertainty is transferred by an AI-based downscaling approach. Quantile-based metrics are here used to measure the ensemble variability between seasonal forecasts and their downscaled products. On the other side, quantile-based metrics can also give an alternative description of the ensemble variabilities, which could replace the raw ensemble members in the downscaling process. In this study, the AI-downscaling system is tested by inputting (a) raw ensemble members and (b) quantile-based metrics. Transferred uncertainty and downscaling accuracy are then evaluated to develop and implement an optimal downscaling approach with hazard-dependent inputs being selected at  regional and local scales. Heidari F., Lin Q., Espitia Sarmiento E.F., Toreti A., and Xoplaki E. (2023): A deep learning technique to realistically bias correct and downscale seasonal forecast ensembles of climate variables towards the development of an AI-based early warning system, EGU 2023 abstract
Towards improved hydro-meteorological ensemble forecasting for flood warning in small catchments in Saxony, Germany
Authors: Grundmann Jens , Wagner Michael , Philipp Andy
Published: February 2023

Flood forecasting and warning for small catchments are challenging due to the short response time of the catchments on heavy rainfall events. Thus, disaster managers are interested in extended lead times to initiate flood defence measures, which can be obtained by employing forecasts of numerical weather models as driving data for hydrological models. To portray the inherent uncertainty of weather model output, ensemble hydro-meteorological forecasts can be used.By this contribution, we introduce the next steps to improve our operational web-based demonstration platform for ensemble hydrological forecasting in small catchments of Saxony, Germany (http://howa-innovativ.hydro.tu-dresden.de/WebDemoLive/). In its current configuration, it uses the Icon-D2-EPS numerical weather prediction product of the German Weather Service (DWD) and provides a hydrologic forecast ensemble of 20 members each three hours, for lead times up to 27 hours. The system is established for three pilot regions with different hydrological settings in Saxony, Germany. Within the second funding period of the HoWa-project improvements are planned for three main parts of the hydro-meteorological ensemble prediction platform considering a) the for observed and forecasted precipitation input, b) the hydrological forecast modelling, and c) the post-processing, visualisation and communication of results including their uncertainty.In terms of precipitation input we are going to incorporate radar based nowcasting for short term forecasts of the next two hours. Furthermore, we will enlarge the maximum forecast period to 48 hours by exploring the full range of the Icon-D2-EPS NWP forecasts. In addition, forecasts will be updated more frequent. Regarding the hydrological forecasting features will be implemented for flood reservoir operation, and the numbers of catchments/regions will be increased. Finally, a new web-based visualisation dash board will be developed to allow for user oriented analysis and configuration. First steps towards these improvements will be presented.
Economic benefits of ecosystem-based disaster risk reduction and ecosystem-based climate change adaptation: a global review
Authors: Vicarelli Marta , Sudmeier-Rieux Karen , Alsadadi Ali , Kang Michael , Leue Madeline , Schütze Simon , Shrestha Aryen , Steciuk Ella , Wasielewski David , Mysiak Jaroslav , McAndrew Shannon , Marr Michael , Vance Miranda
Published: February 2023

Ecosystems and ecosystem services may contribute to reduction in disaster risk, sustainable development and climate change adaptation. The potential of Nature-based Solutions (NbS) is now recognized by major national policies and international framework agreements. However, to date there is limited scientific evidence about their economic viability and equity impacts. In this study we developed a global database of 406 observations from 87 peer-reviewed studies published between 2000 and 2020, completing economic evaluations of NbS for Ecosystem-based Climate Adaptation (EbA) and Ecosystem-based Disaster Risk Reduction (Eco-DRR). We examine available scientific knowledge on the economic viability and performance of NbS for Eco-DRR and EbA, both in terms of efficiency and equity. More than 40% of the studies analyze the role of coastal ecosystems, coral reefs, wetlands, and mangroves in attenuating disaster risk, with a special focus on floods, storms and erosion. Abundant are also studies examining forest ecosystems (30%), followed by urban (25%) and riparian ecosystems (23%). A smaller number of studies analyzes agro-ecosystems. The number of studies per region suggests that Europe, Asia, and North America are the regions where most Eco-DRR research was undertaken. Based on our results, 71% of studies found that the ecosystems studied were effective NbS in mitigating hazards. 24% of studies found that the ecosystems were occasionally effective in mitigating hazards. None of the studies found NbS ineffective in mitigating hazards. The ecosystems most frequently effective in mitigating hazards included mangroves (80%), forests (77%), and coastal ecosystems (73%). A subset of studies compared the efficacy and cost-effectiveness of NbS and engineering-based solutions in mitigating certain hazards (39%). Among these studies, 65% found that NbS are always more effective in attenuating hazards compared to engineering-based solutions, and 26% found that NbS are partially more effective. No study found that NbS are less effective than engineering-based solutions. 
What makes science-and-policy-dialogue successful? Impact analysis of a parliamentary evening in the German Bundestag.
Authors: Heidenreich Marie
Published: February 2023

The term “Science-and-policy-dialogue” in contrast to “Science-to-policy-advise” indicates the need for a dialogue instead of a one-way-advice. Our communication must be needs-based, addressing what’s on the political agenda. The objective is science-based policymaking, which means politicians use high-quality information to inform political decisions. While science-and-policy dialogues face many challenges – e. g. different focal points and timelines of research and politics, no prospect of higher scientific reputation – they are worth the effort because, for apparent reasons, trial-and-error is not an option in Earth system politics.

SynCom is the overarching synthesis and communication platform of the research field 'Earth and Environment' of the Helmholtz Association. SynCom synthesizes research results and builds bridges across various disciplines. Functioning as an interface between science and society, SynCom supports evidence-based climate and environmental politics.

In my talk, I will present the results of an impact analysis of a parliamentary evening on the "climate-resilient city", which we held in November 2022 on the dome of the German Bundestag.
Permafrost evidence near Snezhnika microglaier, Pirin Mountain, Bulgaria
Authors: Georgieva Gergana , Tzankov Christian , Kisyov Atanas , Dragomirov Dragomir , Georgieva Bojourka , Buchakchiev Valentin , Dimitrova Kalina , Ishlyamski Daniel
Published: February 2023

Snezhnika microglacier in Golyam Kazan, Pirin, Bulgaria is considered as the southernmost microglacier in Europe. Its size has been monitored since 1994, but information about its thickness and underlying structure is sparse. In 2018, 2019 and 2020 we conducted geophysical measurements, using ground penetrating radar (GPR) and resistivity tomography (ERT) in order to estimate the thickness and internal structure of the ice body as well as the subsurface structure beneath and near it. The mean thickness estimated from GPR profiles is about 4–6 m, but can reach up to 8 m in the southern part of the ice body. These results are partialy in agreement with the results from early borehole measurements. ERT measurements in the lowest part of the microglacier’s bed show an anomaly with very high resistivity (> 60000 Ωm). The ERT measurements were repeated over 3 consecutive years, and the anomaly was detected during every measurement campaign. The values observed are typical for ice. This can be taken as evidence of permafrost in the Pirin Mountains. Our study provides more information on less investigated distribution of permafrost in low latitude areas, as well as on thickness of microglacier. This data for the thickness of the microglacier can be used for further studies on mass balance monitoring.
Evidence of destructive debris flows at (pre-) Hispanic Cayambe settlements, Ecuador
Authors: Vasconez Francisco J. , Samaniego Pablo , Phillips Jeremy , Andrade S. Daniel , Simbaña Edwin , Nogales Valeria , Román Carrión José Luis , Vásconez Müller Anais , Vásquez María Antonieta
Published: February 2023

In Ecuador, a country with numerous potentially active volcanoes, recurrent large earthquakes, and regular climate-related events, it is surmised that phenomena such as debris flows have affected pre-Hispanic populations since their settlement in ~5000 cal BC. Here, using a multidisciplinary approach, we studied the most recent debris flow events that affected the Cayambe city area, located 15 km west of the active glacier-clad Cayambe volcano. Based on detailed characterization of the deposits, including sedimentological, archaeological, and paleontological analyses, as well as radiocarbon dating. We found that two debris flow (i.e., Río Blanco I and II) destroyed Caranqui settlements in 665–775 cal AD and 774–892 cal AD, respectively, while another event impacted a Spanish colonial farm in 1590 –1620 cal AD (Río Blanco III). The grain size distribution of these deposits indicates a gravel-rich flow for Río Blanco I and clay-rich flow for Río Blanco II and III, whilst componentry suggests low juvenile volcanic content for all three deposits. Juvenile components include pumice and lustrous dense dacites, while accidental clasts are dull dense dacites, oxidized and hydrothermally-altered material, as well as archaeological artifacts. These results, in addition to radiocarbon ages, suggest that the debris flows could either be post-eruptive or not related to volcanic eruptions. Potential non-volcanic trigger mechanisms for these events include rainfall and/or earthquakes, which implies that they can occur at any time and without forecast. Currently, the city of Cayambe is rapidly expanding and, consequently, our findings are relevant for creating impact scenarios for future debris flows forming in the Rio Blanco headwaters and descending to the city.
Influence of the basement on the eruptive dynamics: the case of the Puig de la Banya del Boc volcano, Garrotxa Volcanic Field, NE Iberian Peninsula.
Authors: Cerda Daniela , Pedrazzi Dario , Geyer Adelina , Martí Joan , Aulinas Meritxell , Planagumà Llorenç , de Bolós Xavier
Published: February 2023

During monogenetic eruptions, external controlling parameters such as fracturing patterns, differences in the hydraulic properties and heterogeneities of the basement rocks play an important role in creating small edifices. This is reflected by changes in eruptive styles, deposits as well as the morphology of the volcanic cones.The deposits of the Puig de la Banya del Boc (PBB), a monogenetic volcanic cone located in the Garrotxa Volcanic Field (GVF) are a good example of the complex basement-influenced eruptive behaviour.The aim of this study is to determine the eruptive history and dynamics of the PBB volcano, by means of sedimentological, stratigraphic and lithostratigraphic analyses of its deposits. The PBB cone, located on a hard basement of Palaeozoic metamorphic rocks, was built during a single eruption and it shows a complex eruptive succession with phreatomagmatic, Strombolian, and effusive phases.The succession of deposits of the PBB reveals the influence of the substrate, upon which the volcano forms, in this case the crystalline Paleozoic basement, and its hydrodynamic properties that controlled the way in which magma/water interactions occurred throughout the eruptionThis work represents a further step towards improving the understanding of magma-water interaction in complex environments as the GVF.This work was funded by the BECAS CHILE- ANID, PhD Scholarship Abroad, announcement 2022/Folio 72220257.
Renewable energy forecasting: results of the Smart4RES project and future research directions.
Authors: Kariniotakis Georges , Camal Simon ,   Smart4RES Team
Published: February 2023

The European Horizon 2020 project Smart4RES (http://www.smart4res.eu), which started in 2019 and runs until April 2023, aims at improving modelling and forecasting of weather variables necessary to optimize the integration of weather-dependent renewable energy (RES) production (i.e. wind, solar) into power systems and electricity markets. It gathers experts from several disciplines ranging from meteorology, data science, power systems a.o. It aims to contribute to the pathway towards energy systems with very high RES penetrations by 2030 and beyond.This presentation has a double objective:(1) To present a comprehensive overview in terms of KPI improvements of the final results obtained by the project. These results cover thematic objectives including:Improvement of weather and RES forecasting;
Streamlined extraction of optimal value from the data through data sharing, data market places, and novel business models for the data;
New data-driven optimization and decision-aid tools for market and grid management applications;
Validation of new models in living labs and assessment of forecasting value vs costly remedies to hedge uncertainties (i.e. storage). 
The results obtained are numerous. Without being exhaustive, they include: improved forecasting of weather variables with focus on extreme situations and also through innovative measuring settings (i.e. a network of sky cameras); A seamless approach to couple outputs from different ensemble numerical weather prediction (NWP) models with different temporal resolutions; Advances from ultra-high resolution NWPs based on Large Eddy Simulation; Approaches for RES production forecasting aiming at efficiently combining highly dimensionally input (various types of satellite images, NWPs, spatially distributed measurements etc.); Seamless probabilistic RES forecasting covering multiple time frames and data inputs; Resilient energy forecasting. In the front of applications methods are proposed to optimally use forecasts for the management of storage systems coupled with renewables, for the optimal trading of renewables in multiple markets and for grid management optimization and dynamic security assessment. Prescriptive analytics and explainable AI methods are proposed to optimize decision making.  A cost benefit analysis is performed to assess the contribution of different types of data in forecasting problems.(2) To present hierarchized proposals for future research directions. An international workshop is organized by the project (14/04/2023), where experts are invited to assess where RES predictability stands today and propose research directions for the future. In this presentation we will present the conclusions of this workshop. This will be a useful insight for academics, industrials as well as policy makers in the field.
Modeling the Impact of Geomagnetically Induced Currents on Electrified Railway Signalling Systems in the United Kingdom
Authors: Wild James , Patterson Cameron , Boteler David
Published: February 2023

Studies of space weather impacts on ground-based infrastructure have largely focused on power networks and pipelines, but railway signalling systems are also affected, with misoperations observed in several countries. This paper advances recent theoretical work on geomagnetically induced currents in railway signalling systems by modeling realistic railway lines with parameters from current industrial standards. Focusing on two example lines in the United Kingdom with different locations and orientation, a range of uniform electric fields are simulated along each modelled line. The results show that misoperations could be caused by geomagnetic interference at disturbance levels expected to recur over timescales of several decades. We also demonstrate that the UK estimate for the geoelectric field induced by a 1 in 100-year extreme storm would be strong enough to cause widespread signal misoperations in both lines studied.
Quantitative structural analysis of fracture networks in outcrop analogues of fractured reservoirs: a review of measurement methodologies and statistical techniques
Authors: Bistacchi Andrea , Mayolle Sylvain , Casiraghi Stefano , De Paolo Erica , Martinelli Mattia , Agliardi Federico , La Valle Fabio
Published: February 2023

The characterization and modelling of fractured reservoirs of geofluids are becoming increasingly important in the ongoing energy transition and climate crisis. Fractured reservoirs are fundamental for critical applications such as CO2 sequestration, H2 and natural gas storage, exploitation of geothermal fluids and hydrothermal ore deposits, and management and safeguard of groundwater resources (deep aquifers are considered more resilient in drought scenarios). In addition, the characterization of fracture networks is relevant in earthquake mechanics, slope stability and engineering geology.Characterization of natural fracture systems and fracture networks is often based on characterization of outcrop analogues, with measurement of large structural datasets with a combination of field and remote sensing techniques (e.g. Digital Outcrop Models - DOMs), leading to statistical and topological analysis. Numerous studies provide significant amounts of data from a broad variety of methodologies and protocols used in the field. These methodologies aim at characterizing fracture systems by a large number of parameters. Individual “fracture” sets are characterized by genetic features (e.g. joint vs. stylolite), relative chronology, spatial distribution (regular, random, clustered...), density and intensity (e.g. P20 and P21), and by statistical distributions of spacing, orientation, length, height, and aperture (the latter being a dynamical property that varies with fluid pressure and confining stress). Fracture networks composed by several sets are also characterized by topology and connectivity (characterized for instance in terms of fracture terminations or with graphs).Here we propose a thorough review, supported by rich case studies, of quantitative methods for fracture network characterization and analysis on DOMs. This review aims at determining the most relevant and efficient methods for field and remote-sensing measurement, and best-practice statistical analysis techniques, in order to accurately characterize outcrop analogues that can be used to model fractured reservoirs.
The Effects of Meteorological Parameters on GNSS Height Component
Authors: Tekin Ünlütürk Nihal , Doğan Uğur
Published: February 2023

In this study, when the height components of continuous GNSS stations were examined, it was seen that there were seasonal effects, and it was investigated whether the height components were related to meteorological parameters. Linear regression analysis was performed to obtain how dependent the height components of the continuous GNSS stations were on meteorological parameters. As a result of the analysis, the height components of the continuous GNSS stations are dependent on the meteorological parameters such as temperature, pressure, relative humidity, wind velocity and precipitation. In addition, height component time series analysis of continuous GNSS stations was performed by using Autoregressive Moving Average (ARMA) models from linear time series methods. As a result of the study, the performance of the ARMA modeling results again indicated the dependence of the height component of the continuous GNSS stations on the meteorological parameters.Moreover, the measurements of Turkish National Permanent GNSS Network-Aktif (TUSAGA-Aktif) stations covering the 2014-2019 date range were used. The daily coordinates of GNSS stations were obtained as a result of GAMIT/GLOBK software solution. The analyzes subject to the study were carried out in Python.Keywords: GNSS height component, Meteorological parameters, Linear Regression, ARMA Model
Representation, evolution and validation of the stratopause and stratospheric contraction in reanalyses data
Authors: de la Torre Laura , Añel Juan Antonio , Kuchař Aleš , Sacha Petr
Published: February 2023

Recent work using models from the Chemistry-Climate Model Initiative shows that the stratopause is descending and that the stratosphere has contracted substantially over the last decades, being the increasing concentrations of greenhouse gases (GHGs) the main driver. This stratospheric contraction is not a mere response to stratospheric cooling, as changes in both tropopause and stratopause pressure contribute significantly to it.Here we present the evolution over the last decades of the stratopause and stratospheric thickness in the main reanalyses datasets: MERRA-2, JRA-55, and ERA5.1. We compare them to model results with WACCM-X and satellite observations (GOMOS, MLS and SABER). For our computations, we consider the discontinuity problems in temperature at stratopause heights suitable to affect its structure and behaviour due to the assimilation of new observational data as they become available.Our results show that there is high variability in the percentages of stratopauses and their height, a significant dependence on the latitude and dataset for the stratopause height and limitations of JRA-55 to represent elevated stratopause cases (probably linked to sudden stratospheric warnings) over the polar regions because of its low-top compared to other reanalyses.
Past and present monitoring results of acid mine drainage around copper mines and smelter in Bor, Serbia
Authors: Stefan Dordievski
Published: February 2023

The first recorded environmental protests in Bor, Serbia, began in 1906, only 3 years after the mining and smelting of copper ores started. In 1931, one of the first results of chemical analysis of river water were issued, stating that the content of free acid (as H2SO4) in Bor River just after the mine was 0.0168 %. Another report from 1935 stated that the pH value of Bor River was 4.5, the concentration of Fe was 81 mg/L, and the concentration of Cu was 22 mg/L. At that time, sampling and analysis of river water were initiated by the rebellious local community who wanted compensation for the damage made to their agricultural fields. Throughout the years, the pollution of Bor River became a norm, and researchers from Serbia and the world investigated the pollution from the physical, chemical, mineralogical, and microbiological aspects. From 2015 to 2021, the pH value of Bor River ranged from 2.1 to 6.3, the concentration of Fe ranged from 66 to 355 mg/L, and the concentration of Cu ranged from 4 to 116 mg/L, depending on the intensity of mining and smelting activities. These more recent results are not so different from those about a century before. However, since the mining and smelting combine Bor changed its ownership in 2018, the monitoring of the pollution became more advanced, and there are more reclamation activities. Several automatic monitoring stations with inductively coupled plasma optical emission spectrometers or mass spectrometers (ICP-OES or ICP-MS) were installed in the field by the polluted rivers for the purpose of monitoring. Water from the largest acid mine drainage accumulation, the Robule Lake, was treated, drained, and in 2023. the Robule Lake does not exist anymore. Additional monitoring and reclamation activities are expected which could reduce the pollution of Bor River in the future.
Forced subduction initiation near spreading centers: effects of brittle-ductile damage
Authors: Liu Mingqi , Gerya Taras
Published: February 2023

Although positive buoyancy of young lithosphere near spreading centers does not favor spontaneous subduction, subduction initiation occurs easily near ridges due to their intrinsic rheological weakness when plate motion reverses from extension to compression. It has also been repeatedly proposed that inherited detachment faults may directly control the nucleation of new subduction zones near ridges subjected to forced compression. However, recent 3D numerical experiments suggested that direct inversion of a single detachment fault does not occur. Here we further investigate this controversy numerically by focusing on the influence of brittle-ductile damage on the dynamics of near-ridge subduction initiation. We self-consistently model the inversion of tectonic patterns formed during oceanic spreading using 3D high-resolution thermomechanical numerical models with strain weakening of faults and grain size evolution. Numerical results show that forced compression predominantly reactivates and rotates inherited extensional faults, shortening and thickening the weakest near-ridge region of the oceanic lithosphere, thereby producing ridge swellings. As a result, a new megathrust zone is developed, which accommodates further shortening and subduction initiation. Furthermore, brittle/plastic strain weakening has a key impact on the collapse of the thickened ridge and the onset of near-ridge subduction initiation. In contrast, grain size evolution of the mantle only slightly enhances the localization of shear zones at the brittle-ductile transition and thus plays a subordinate role. Compared to the geological record, our numerical results provide new helpful insights into possible physical controls and dynamics of natural near-ridge subduction initiation processes recorded by the Mirdita ophiolite of Albania.
Deformation bands characterization in porous carbonates: a case study from the Matera High (Southern Italy)
Authors: Freda Giovanni , Mittempergher Silvia , Balsamo Fabrizio , Di Cuia Raffaele , Ricciato Angelo
Published: February 2023

Faults and fractures have a crucial role in controlling the permeability in carbonate reservoirs, as they can act as a conduit or barrier for fluid flow. Reservoir-scale outcrop analogue studies provide a useful tool to investigate their spatial distribution and connectivity and to establish the relationships between small-scale structures with larger structures that can be identified in the subsurface.In this contribution, we describe the preliminary results of a structural study carried out in the Matera's High, South Italy, as an analogue for porous carbonate structures that could be used as CO2 storage fields. Matera High is located on the western side of the Murge region, at the boundary between the Apulian foreland and the foredeep of the southern Apennines thrust belt. It consists of an asymmetrical horst structure involving the Cretaceous carbonates of the Apulian platform (Calcare di Altamura). The Calcare di Altamura is unconformably overlain by Plio-Pleistocene shallow-marine coarse-grained carbonates (Calcarenite di Gravina). The Calcare di Altamura is moderately tilted and is characterised by NW-SE striking normal faults with a throw variable from centimetres to tens of meters. The Cretaceous sequence is also characterised by widespread joints, whose intensity increases approaching faults. The Plio-Pleistocene carbonate succession has very few faults. It is dominated by deformation bands organized into 3 main sets dipping at high angles and striking N-S, NW-SE, and NE-SW. This geological setting allows us to conduct a detailed structural study on an area of about 80 km2, investigating how deformation structures affect the secondary porosity in tight limestone and porous calcarenites. The study was conducted at multiple scales in the field and laboratory and includes (1) geological mapping and structural measurements of faults, fractures and deformation bands; (2) use of linear scan-lines to characterise the deformation bands density across faults; (3) use of photogrammetric techniques to obtain Virtual Outcrop Models (VOMs); (4) development of 3D model based on statistical and topological analysis obtained from scan lines and scan areas in the field and VOMs, (5) petrophysical logging (uniaxial strength, in situ permeability, gamma ray) to highlight the factors that control the formation of the deformation bands, (6) image analysis of blue-resin impregnated thin section and optical cathodoluminescence images, and (7) He-density and Hg-intrusion porosimetry to quantify host rock and deformation bands porosity and pore size distribution.The preliminary results suggest that the combination of fieldwork, VOMs and laboratory measurements allow the characterization of the deformation bands with more confidence to obtain conceptual and quantitative models about its effects on the fluid flow which can be used for reservoirs characterization for CO2 sequestration.
Growth reduction and alteration of nonstructural carbohydrate (NSC)allocation in a sympodial bamboo (Indocalamus decorus) under atmospheric O3 enrichment
Authors: Li Li
Published: February 2023

Regional increases in atmospheric O3, mainly produced photochemically from anthropogenic precursor gases, have phytotoxicity due to its strong oxidizing properties. To determine the response of bamboo physiology to elevated O3 levels, three-year-old dwarf bamboo (Indocalamus decorus) clones were exposed to three O3 concentrations (Ambient-AA, 21.3 to 80.9 ppb in the daytime; AA+70, 70 ppb O3 above ambient; AA+140, 140 ppb O3 above ambient) in open-top chambers for one growing season in Beijing, China. Gas exchange, biomass, growth, soluble sugar, and starch contents were examined at the end of the experiment. Our findings indicated that: (1) elevated O3 treatments decreased the photosynthesis rate, total biomass, and bud numbers but increased individual bud biomass and rhizome bud to rhizome biomass ratio. The most severe reduction was observed in new rhizome biomass (35.9% reduction in AA+70 and 57.2%reduction in AA+140), whereas individual bud biomass increased by 50%and 75%in the AA+70and AA+140 groups compared with AA, respectively; (2) the starch contents in the rhizome decreased by 28.4%, whereas soluble sugar increased by 38.1% in the AA+140 rhizome buds compared to AA; (3) only the culm numbers of pachymorph rhizomes (clumped) decreased, whereas no changes in leptomorph rhizomes were observed. However, the mean distance between two ramets was lengthened by 49.4% and 86.5% in AA+70 and AA+140, respectively. In conclusion, Indocalamus decorus allocated more nonstructural carbohydrates (NSCs) from the rhizome to the buds to form stronger buds and ensure the survival of newer generations as a high priority in response to O3 exposure. Indocalamus decorus may be conducive to escaping from disadvantaged habitats and decreasing resource competition by lengthening the distance between two ramets.
Gravity Wave Phase Speeds, Wavelengths, and Momentum Fluxes Observed Above the Southern Ocean
Authors: Green Brian , Sheshadri Aditi
Published: February 2023

From March to December 2014, Loon LLC flew 107 super-pressure balloons in the lower stratosphere over the Southern Ocean. Their GPS sampling frequency of 1Hz allowed them to sample motion associated with atmospheric internal gravity waves generated by the Andes mountains, small islands, and non-orographic sources such as fronts. Analyzing the balloons’ data time series using wavelets, we present distributions of the gravity waves’ momentum fluxes, phase speeds, and wavelengths, both in the time-mean and as they vary from month to month. Many climate models parameterize gravity waves using a phase speed-momentum flux relationship, so we focus on the relationship between those quantities.
Numerical and analytical modelling of bending-induced tensile fractures
Authors: Schöpfer Martin , Grasemann Bernhard , Hinsch Ralph
Published: February 2023

Although the origin of outer-arc extension fractures in folded sequences is well-understood and documented in many natural examples, geometric and geomechanical factors controlling their spacing are hitherto unexplored. This study investigates the formation of bending-induced tensile fractures during constant-curvature forced folding using two-dimensional Distinct Element Method (DEM) numerical modelling. The DEM model comprises a central brittle layer embedded within elastic layers; the layer interfaces are cohesionless. Folding of this three-layer system is enforced by a velocity boundary condition at the model base, while a constant overburden pressure is maintained at the model top.The models illustrate several key stages of fracture array development: (i) Prior to the onset of fracture, the neutral surface is located midway between the layer boundaries, consistent with pure bending; (ii) Once the outer-fibre stress equals the tensile strength of the layer, fractures nucleate and propagate through the brittle layer; (iii) The rate of fracture formation as a function of curvature decreases nonlinearly, with new fractures developing approximately midway between two existing fractures; (iv) Eventually no new fractures form, irrespective of any further increase in fold curvature, a state referred to as fracture saturation.On the basis of these numerical model results, an approximate analytical solution for fracture spacing based on classic beam theory is developed. The predicted range of fracture spacing as a function of fold curvature is in good agreement with the numerical model results. Importantly, the analytical solution reveals which geometric and geomechanical factors control fracture spacing, namely layer thickness, radius of curvature, Young’s modulus, tensile strength and confining pressure. The fracture spacing to layer thickness ratio at saturation however depends only (nonlinearly) on the ratio of tensile strength to overburden pressure.The numerical model results are qualitatively compared with field observations at outcrops located in the Montpellier Fold region. The folded lithologies are of Jurassic age and comprise (brittle) limestones, with (ductile) marl intercalations. Fracture-bound limestone blocks located within the fold hinges and observed on the fold-profile plane are laterally bound by V-shaped veins that thin towards the fold core. In the inner-arc of each vein-bound limestone block, the marl interbed thickens towards the veins, whereas in the outer-arc it thins towards the veins. Clearly, the thickness distribution of the marl interbeds reflects non-uniform loading, which is consistent with the loading conditions hypothesised on the basis of the theoretical models.
Modeling influence of sea ice on gas exchanges between atmosphere and ocean in a global Earth System Model
Authors: Torsvik Tomas
Published: February 2023

Global Earth System Models (ESMs) seek to simulate physical, chemical and biological processes that are relevant for the evolution of global climate. One key feature of an ESM is the ability to simulate fluxes of greenhouse gases and aerosols between the atmosphere and ocean, keep track of the inventories in the respective model components and allow for feedback on the climate system. These fluxes are usually calculated based on bulk formulations derived from open water measurements, and are restricted by the sea ice fraction in regions covered by sea ice.The air-sea gas exchange is determined by the difference in concentration across the air-sea interface, and a gas transfer velocity that is specific for the gas in question. Using CO2 as example, the air-sea gas exchange is           FCO2 = (1 - βCsea-ice ) ⋅ kw(CO2) ⋅ ( [CO2]sea - α[CO2]air)   (1)where Csea-ice is the sea ice concentration, kw(CO2) is the gas transfer velocity, and α is the Ostwald solubility coefficient. Traditional formulas use β = 1 (complete barrier), but in order to account for cracks and leads in the sea ice, Steiner et al. (2013) proposed a modified formula with β ∈ [0, 1], allowing the sea ice to act as a partial barrier (0 < β < 1) or allowing free exchange in sea ice covered regions (β = 0).We implement the modified gas exchange formula (eq. 1) in the Norwegian Earth System Model NorESM2, for all model tracers exchanged over the air-sea interface (CO2, O2, N2, N2O, DMS). Experimenting with different β values, we find that small increases (β ∈ [0.01, 0.02]) may result in either increased or decreased gas fluxes in high latitude regions. This can be attributed to the internal variability of the sea ice area, in particular for the summer minimum, which responds to changes in greenhouse gases and aerosols in the atmosphere. For β ∈ [0.1, 0.2] we find an increase in CO2 flux of 16% — 22% north of 68°N, and 5% — 8% south of 60°S. Observational datasets based on eddy covariance data for CO2 in the atmospheric boundary layer will be used infuture work in order to determine a realistic range for β.REFERENCES:N. S. Steiner, W. G. Lee, and J. R. Christian. Enhanced gas fluxes in small sea ice leads and cracks: Effects on CO2 exchange and ocean acidification. Journal of Geophysical Research: Oceans, 118(3):1195–1205, 2013. doi: 10.1002/jgrc.20100.
Groundwater resources in barrier islands are vulnerable to storm-surge salinization through various dominating processes, as revealed by data-based modeling
Authors: Frederiks Ryan S. , Paldor Anner , Donati Lauren , Michael Holly A.
Published: February 2023

Groundwater resources on barrier islands sustain both human lives and ecosystem functioning worldwide. A critical threat to these vital freshwater resources is the projected increase in frequency of storm-surges with climate change. These extreme events have the potential to salinize the aquifer, which increases the mortality of stabilizing vegetation and potentially causes substantial erosion. It is important to understand which types of systems are most vulnerable to better plan mitigation efforts. To that end, we collected data on water level and salinity at three different barrier islands along the east coast of the US. These study sites span a range of barrier island typologies, including differences in topography, vegetation, overwash frequency and connection to the ocean. The relationship between the various processes and the vulnerability to salinization was quantified using transfer function noise models (Pastas) and cross correlation. It was found that changes in groundwater head can be well represented with bay water levels, ocean water levels, recharge (both precipitation and evapotranspiration), and overwash events (periods of time when bay or ocean water levels exceed the land surface elevation of the wells). The data-based models indicate that ocean/bay levels are the primary driver of water level change close to the shore while in the center of the barrier islands precipitation is a more significant driver. Substantial differences were found between the different sites in terms of the dominating factors and the overall vulnerability. A sheltered maritime forest site showed minimal impact from storm surge overwash while a less sheltered marsh and maritime forest site showed a clear relationship between the height and duration of overwash events and the total amount of salinity observed in the wells. Finally, at a barren high energy beach site, storm surge appeared to both salinize the aquifer from the top and raise the freshwater-saltwater interface from below. These findings have important implications for management of barrier island groundwater resources, which is a vital resource that is compromised by future changes in storm surge frequency and intensity.