bluuebunny/crossref_metadata_2025 huggingface dataset:
Deep ultra-hot melting in cratonic mantle roots
Authors: Walsh Carl , Kamber Balz , Tomlinson Emma
Published: March 2022

The persistence of Archaean cratons for >2.5Ga was aided by thick, mechanically strong, and cool lithospheric mantle keels up to 250km deep. It is widely accepted that the cratonic mantle, dominated by depleted harzburgite, lherzolite and dunite, was formed by extensive melt extraction from originally fertile mantle peridotite. Models seeking to explain the formation of deep cratonic mantle in the garnet and diamond stability fields, initially sought to answer how such rocks could form in-situ at high temperatures and pressures and envisaged large-scale thermochemical plume upwellings. More recently, mineralogical and geochemical observations, namely the high Cr content of garnet and low whole rock HREE concentrations in cratonic harzburgites, have led to the conclusion that the deep cratonic mantle couldn’t have originally melted in the garnet stability field.  Mechanical stacking of shallowly depleted oceanic lithosphere was therefore proposed to have thickened the depleted lithosphere cratonic roots. In this process, the spinel facies minerals are envisaged to transform into the garnet stability field.

Here we present the first results of combined thermodynamic and geochemical modelling at temperatures high enough to reconcile the very refractory residues. We found that the requirement for initially shallow melting is no longer supported. Deep (150-250km), ultra-hot (>1800°C), incremental melting can produce the mineralogical and geochemical signatures of depleted cratonic harzburgites. The modelling also implies a link between areas of extreme depletion in the deep lithospheric mantle and the genesis of Earth’s hottest lavas (Al-enriched komatiite) by re-melting depleted harzburgite. Diamond inclusion minerals have a well-documented skew to the most refractory compositions found in cratonic peridotite. We propose that these ultra-depleted, highly reducing regions of the lithospheric root possess the highest diamond formation and preservation potential.
Lateral change of  ELMU–LOMU sources for Cenozoic volcanic rocks from Southeast Mongolia and North China: Tracing zonation of solidified Hadean magma ocean 
Authors: Chuvashova Irina , Rasskazov Sergei , Sun Yi-min , Yasnygina Tatiana , Saranina Elena
Published: March 2022

In terms of Pb isotope ratios, melting anomalies of Central and East Asia show no high μ (HIMU, high 238U/204Pb) signature that was generated on the Earth about 2 Ga ago and was caused by sulfide sequestration of Pb from the mantle to the core [Hart and Gaetany, 2006]. In such particular environment, we use Pb isotope data on Late Phanerozoic volcanic rocks to develop general systematics of their sources through definition of initial viscous protomantle reservoirs with low μ and elevated μ signatures (LOMUVIPMAR and ELMUVIPMAR, respectively) that imply a solidification time of the mantle in the Hadean magma ocean between 4.54 and 4.44 Ga ago. We suggest that the protomantle reservoirs retained specific Pb isotope signatures in the early, middle, and late epochs of the Earth's evolution (4.54–3.6, 2.9–1.8, and  <0.7 Ga ago, respectively) [Rasskazov et al., 2020]. In this presentation, we report the first representative Pb isotope data on the ELMU signature of Late Cenozoic rocks from the Dariganga volcanic field, Southeast Mongolia. Pb isotope secondary-isochron patterns of volcanic rocks show protomantle material that was not differentiated between 4.474 and 4.444 Ga (i.e. directly ascended from a deep mantle reservoir in the Cenozoic). In addition, the material was also differentiated in the deep mantle at about 3.69, 2.16, and 1.74 Ga. Pb isotope data on volcanic fields of North China are indicative for lateral change from the ELMU to LOMU signature (Figure). We infer that sources of volcanic rocks from Southeast Mongolia and North China display the primary inhomogeneity of the deep mantle that was generated in the Hadean magma ocean from its initial solidification as early as 4.54 Ga to its final respond of 4.44 Ga.   

Hart, S.R. &  Gaetani, G.A. (2006). Mantle paradoxes: the sulfide solution. Contrib. Mineral. Petrol., 152, 295–308.

Rasskazov, S., Chuvashova, I., Yasnygina, T., & Saranina, E. (2020). Mantle evolution of Asia inferred from Pb isotopic signatures of sources for Late Phanerozoic volcanic rocks. Minerals, 10 (9), 739. 
Understanding the Information Content in the Hierarchy of Model Development Decisions: Learning From Data
Authors: Gharari Shervan , Gupta Hoshin , Clark Martyn , Hrachowitz Markus , Fenicia Fabrizio , Matgen Patrick , Savenije Hubert
Published: March 2022

Process-based hydrological models seek to represent the dominant hydrological processes in a catchment. However, due to unavoidable incompleteness of knowledge, the construction of “fidelius” process-based models depends largely on expert judgment. We present a systematic approach that treats models as hierarchical assemblages of hypotheses (conservation principles, system architecture, process parameterization equations, and parameter specification), which enables investigating how the hierarchy of model development decisions impacts model fidelity. Each model development step provides information that progressively changes our uncertainty (increases, decreases, or alters) regarding the input-state-output behavior of the system. Following the principle of maximum entropy, we introduce the concept of “minimally restrictive process parameterization equations—MR-PPEs,” which enables us to enhance the flexibility with which system processes can be represented, and to thereby investigate the important role that the system architectural hypothesis (discretization of the system into subsystem elements) plays in determining model behavior. We illustrate and explore these concepts with synthetic and real-data studies, using models constructed from simple generic buckets as building blocks, thereby paving the way for more-detailed investigations using sophisticated process-based hydrological models. We also discuss how proposed MR-PPEs can bridge the gap between current process-based modeling and machine learning. Finally, we suggest the need for model calibration to evolve from a search over “parameter spaces” to a search over “function spaces.”
Methane flux and its relationship with carbon dioxide emission in urban residential areas in Seoul, Korea.
Authors: Lee Keunmin , Hong Je-Woo , Hong Jinkyu
Published: March 2022

Methane (CH4) is the second most important greenhouse gas. However, the measurement of urban CH4 flux is exceptionally scarce. Here we present the observational results based on the eddy-covariance method at the high-rise and high-population residential area in Seoul, Korea. The magnitude and temporal variation of CH4 flux show a significant strong relationship with carbon dioxide emission rate. The observed emission rate of CH4 over the residential area is 21.8 nmol m-2 s-1 on average, and this is corresponding to 11 gC m-2 yr-1 which is comparable with boreal, taiga, and temperate wetlands. The carbon-isotope compositions (δ13C) of CH4 (about -46‰) and CO2 (about -28‰) point to the same source for both gases suggesting vehicular traffic as a dominant source for CH4 in this study. 

This study is supported by “National Adaptation Plan for Climate Change” (2022-001-01), conducted by the Korea Environment Institute (KEI) upon the request of the Korea Ministry of Environment, and the Korea Meteorological Administration Research and Development Program (grant no. KMI2021-01610).
How does baseflow contribution affect catchment C-Q relationships? A continental synthesis using a Bayesian Hierarchical Model
Authors: Guo Danlu , Minaudo Camille , Lintern Anna , Bende-Michl Ulrike , Liu Shuci , Zhang Kefeng , Duvert Clement
Published: March 2022

Understanding concentration-discharge (C-Q) relationships is critical to inform catchment export processes for solute and particulates. The contribution of baseflow to streamflow has been found to affect C-Q relationships in some catchments in previous studies. Current understanding on the effects of baseflow contribution in shaping the C-Q patterns is largely limited to temperate catchments, but we still lack quantitative understanding of these effects across a wide range of climates (e.g., arid, tropical and subtropical). The study aims to assess how baseflow contributions within individual catchments influence C-Q slopes across Australia. The wide range of hydro-climatic regimes and land use/land cover conditions in Australian catchments make this continent the ideal experimental field to gain such an understanding. We analyzed 157 catchments in Australia spanning five climate zones, for six water quality variables: electrical conductivity (EC), total phosphorus (TP), soluble reactive phosphorus (SRP), total suspended solids (TSS), the sum of nitrate and nitrite (NOx) and total nitrogen (TN). The impact of baseflow contributions was defined by the median and the range of daily baseflow indices (BFI_m and BFI_range, respectively) for each catchment. A novel Bayesian hierarchical model was developed to synthesize these effects for individual catchments across the continent.  

Sediments and nutrient species (TSS, NOx, TN and TP) generally show positive C-Q slopes for most catchments, suggesting a dominance of mobilization export patterns. Further, TSS, NOx and TP show stronger mobilization (i.e., steeper positive C-Q slopes) in catchments with higher values in both the BFI_m and BFI_range, while these two metrics are also positively correlated for most catchments. The enhanced mobilization in catchments with higher BFI_m or BFI_range might be explained by more variable flow pathways in catchments with higher baseflow contributions. In such catchments, the more variable flow pathways can lead to higher concentration gradients between low flows and high flows. These gradients are due to  different dominant flow pathways and contributions of groundwater/slow subsurface flow and surface water sources. Our results highlight the need for further studies focusing on identifying and quantifying: a) the influences of temporal variations of baseflow contributions on flow pathways, and b) the impacts of variable flow pathways on catchment C-Q relationships.
Can the crustal strength in the brittle-plastic transition zone be estimated from the flow stress of calcite mylonite?
Authors: Yokoyama Hiroaki , Muto Jun , Nagahama Hiroyuki
Published: March 2022

Quantifying crustal strength is essential to understanding lithosphere strengths and tectonic processes, such as long-term fault movements caused by plate motions. In this study, we estimated the strength of granitic upper crust using recrystallized grain size piezometer of calcite mylonite intercalated in the Cretaceous granitic Abukuma Mountains. In addition, Raman carbonaceous material thermometer was used to constrain the deformation temperature. Calcite mylonites are originated from Late Carboniferous Tateishi Formation and locate along Shajigami shear zone at eastern margin of Abukuma Mountains, Northeastern Japan. Shajigami shear zone is a strike-slip shear zone active during the Middle Cretaceous. Along Shajigami shear zone, calcite mylonite and granitic cataclasites expose.

Calcite grains are well recrystallized, and the grain size are determined by electron backscattered diffraction (EBSD) mapping with the step sizes of 2-2.5µm. The mean grain sizes are 17-26 µm. The differential stress estimated by recrystallized grain size piezometer of calcite aggregate (Platt and De Bresser, 2017) is 35-80 MPa. The estimated metamorphic temperature using the Raman carbonaceous material thermometer (Kouketsu et al., 2014) is 340-250 ˚C. The difference in estimated metamorphic temperature is attributed to the thermal effects of the Cretaceous granitoids that penetrated along the calcite mylonite. This is because the estimated metamorphic temperature is higher the closer to the granitoid. Because well dynamically recrystallized calcite grains indicate that the deformation temperature exceeding 200˚C, the estimate by Raman carbonaceous material thermometer is the upper bound for the deformation temperature.

The calcite mylonite and the granitic cataclasite are thought to have formed at the same time in the Shajigami shear zone (Watanuki et al., 2020). Although there is a slight temperature gradient near the granite, widespread deformation has occurred in this area. The deformation temperature obtained in this study is the deformation around the brittle-plastic transition zone of the upper crust. Hence, the collecting flow stress estimated from calcite mylonite intercalated in brittle granitic shear zone may be possible to constrain the stress magnitude of the shear zone data near the brittle-plastic transition at 200-300°C.

 

References

Platt and De Bresser, 2017, J. Struct. Geol., 105, 80-87.

Kouketsu et al., 2014, Island arc, 23, 33-50.

Watanuki et al., 2020, J. Struct. Geol., 137, 104046.
Combined multifractal analysis of wind power production and atmospheric fields using simultaneous measurement of high-resolution data
Authors: Jose Jerry , Gires Auguste , Schnorenberger Ernani , Tchiguirinskaia Ioulia , Schertzer Daniel
Published: March 2022

Atmospheric fields are known to exhibit extreme variability over wide range of temporal and spatial scales, which makes them complex to characterize. When it comes to wind power production, the power available at atmosphere and power extracted by turbines at multiple scales are affected by corresponding variations in coexisting fields. Understanding their variability and correlations helps in quantifying uncertainties in modeling as well as real data analysis. Here, we aim to characterize the variability and correlations across scales of wind power production, and atmospheric fields including 3D wind, rainfall and air density using simultaneous measurements in a wind farm relying on the framework of Universal Multifractal (UM) analysis. It is a widely used, physically based, scale invariant framework for characterizing and simulating geophysical fields over wide range of scales.

Towards this, high-resolution atmospheric data collected from a meteorological mast located in the wind farm of Pays d’Othe operated by Boralex (110 km south-east of Paris, France) is used. The data is being collected under the project RW-Turb (https://hmco.enpc.fr/portfolio-archive/rw-turb/; supported by the French National Research Agency (ANR-19-CE05-0022). The campaign utilizes multiple 3D sonic anemometers (manufactured by Thies), mini meteorological stations (manufactured by Thies), and disdrometers (Parsivel2, manufactured by OTT) installed at turbine hub height along with turbines in the wind farm. The temporal resolution is 100 Hz for the 3D sonic anemometers, 1 Hz for the meteorological stations and 30 s for the disdrometers. Variability in power production is examined according to different meteorological conditions using the framework of UM and consequences of their correlations are discussed. In the process we also make short commentary on the actual sampling resolution at which fields should be considered for extracting useful statistical information about their variability.
Spatial relationship between extreme rainfall anomalies and density of the triggered landslides
Authors: Mtibaa Slim , Tsunetaka Haruka
Published: March 2022

Precipitation extremes affect the landscape differently and often drive numerous landslides widespread with disparate densities and features. Revealing the factors that govern this spatial variability is critical for understanding landslide susceptibility and developing prediction models. To this end, examining the peculiarities of the triggering rainfall event at spatial and temporal scales emerges as a promising method. Here, we relied on radar gauge-analyzed (R/A) rainfall estimates (period > 30 years, spatial resolution ≈ 5 km) and a landslide inventory for studying the spatial relationship between rainfall anomalies and triggered landslide density. The landslide inventory counts more than 7,600 shallow landslides distributed in about 550 km2 and triggered by an extreme rainfall event that hit the Kyushu area in southern Japan in July 2017. A total of 23 R/A cells with different landslide densities were identified from the landslide inventory. A standard period of 72 h (Pstd), where the cumulative rainfall during the triggering event is maximum, was used to evaluate the spatial rainfall peculiarities at short (1 – 24 h) and long (48 – 72) timescales. Subsequently, rainfall anomalies were discussed by plotting the mean intensities computed at multiple timescales within the Pstd in the intensity duration frequency (IDF) curves developed for each R/A cell. The spatial density of triggered landslides was strongly influenced by the rainfall intensities that exceeded the 100-years return levels at disparate timescales and demonstrated anomalies. More than 65 % of the triggered landslides were located in only three R/A cells. In these cells, rainfall intensities of the triggering event exceeded the 100-years return level at the various timescales (from short to long) within the Pstd, favoring numerous landslides of different geometric features. Rainfall intensities in cells with low landslide density reached the 100-years return levels at short timescales (3 – 24 h). However, this was not necessarily achieved in all low landslide density R/A cells. These preliminary results highlighted the spatial impacts of rainfall anomalies computed at multiple timescales on landslide densities and features and motivated further analysis.
Radioactivity in building materials
Authors: Telloli Chiara , Salvi Stefano , Rizzo Antonietta , Taddei Fabio , De Maria Alice , Marrocchino Elena , Vaccaro Carmela
Published: March 2022

All building materials have a small but not negligible amount of natural radioactivity; since they come from the earth’s crust, this radioactivity is due to the radioactive families of Uranium (U-238), Thorium (Th-232), and Potassium (K-40), in varying concentrations depending on the type and origin of the original rocks.

Some granites and some tuffs can sometimes record significant concentrations of radioisotopes, while in marbles and carbonate stones radioactivity is rarely present unless they are settled in lagoon environments (i.e., Lecce, Italy limestones). Also building products fabricated with naturally occurring radioactive materials (NORM) can exhibit residual radioactivity, such as in various types of sand, ceramics, or cements.

The radioactive content in the materials used to build is therefore of a certain importance because it can significantly affect the annual effective dose equivalent absorbed due to the long residence time of people inside the buildings.

In Italy the reference regulatory device in the field of work activities involving the presence of natural sources is Legislative Decree 230/95 (including subsequent amendments and additions), while the radioactive content of construction materials is regulated by the Legislative Decree 101/2020.

In order to avoid excessive alarms or, on the contrary, to underestimate the problem, a cognitive investigation was carried out on the radioactivity content in ornamental and structural building materials, in order to possibly identify critical radioactivity concentration. The natural stones analyzed are granite rocks sampled in Sardinia (Ornamental Stones District of Gallura).

The analyses were done in the ENEA’s Environmental Traceability and Radiometry Laboratory specialized in low and very low activity concentration of radioisotopes in the environment. The gamma spectrometry analyses were carried out on the samples reduced to grains, to which, following the EC guidelines, the criteria on the criticality of the materials were applied, calculating three parameters: the activity concentration index (I), the gamma absorbed dose rate (Da) and the annual effective dose (He). The results indicate low concentrations of Uranium and Thorium and therefore compliance with the legislation limits concerning the radio-exposure from minerals, so that they can be used for ornamental purpose in buildings.
Variation Characteristics of PM2.5 and PM10 Concentration and its Driving Factors in the Yangtze River Economic Belt
Authors: Yao Yao , He zi qi
Published: March 2022

Studying the changes of PM2.5 and PM10 in the Yangtze River Economic Belt will help promote the comprehensive management of regional air pollution and promote the ecological environment protection and high-quality economic development of the Yangtze River Economic Belt. This paper selects monthly observation data of six pollutants from 126 cities in the Yangtze River Economic Belt from 2015 to 2020, and applies Mann-Kendall mutation test, Pearson correlation coefficient analysis, spatial autocorrelation analysis and spatial regression analysis to study PM2.5 and PM10 temporal and spatial distribution, evolution characteristic and driving factors, and applies the HYSPLIT backward trajectory analysis model to study the potential impact of long-distance air transport and atmospheric boundary layer conditions on the diffusion and transmission of PM2.5 and PM10 pollution sources in the Yangtze River Economic Belt. The annual average concentrations of PM2.5 and PM10 in the Yangtze River Economic Belt significantly decreased year by year, with obvious seasonal trend of high concentration in winter and low concentration in summer. There is a significant positive spatial correlation relationship, and the spatial accumulation is obvious. In addition, there is a significant positive correlation and homology with other gaseous pollutants. The air mass retrospective direction and atmospheric boundary layer conditions of the upper, middle and lower Yangtze River urban agglomerations have different effects on PM2.5 and PM10. The regional GDP, the proportion of the secondary industry, the population density and the green coverage rate in the built-up areas all affected positively the local PM2.5 and PM10 concentrations. Overall, regional cooperating depollution, synergetic reduction of various air pollutants and transformation of economic development patterns can fundamentally solve the problems of PM2.5 and PM10 pollution in the Yangtze River Economic Belt.
Inhibitors of calcification related enzyme affect calcification in foraminifera
Authors: Toyofuku Takashi , Nagai Yukiko
Published: March 2022

Calcareous foraminifera is microfossils that are essential tools for geochemical paleoenvironmental analysis. However, they are also significant producers of calcium carbonate in the marine environment, contributing to the global carbon/calcium cycle in the ocean. As long as anthropogenic carbon dioxide continues to be released into the atmosphere via human activities, carbon dioxide uptake by the oceans will continue to increase, making ocean acidification an ongoing and inevitable social problem recognized internationally. The equilibrium of the carbonate system is expected to be unfavorable to calcification under developed ocean acidification. Numerous observations have been made on various calcifying organisms to evaluate the effects of ocean acidification through field and laboratory culture experiments. Different taxonomic groups are affected by ocean acidification in different ways. Ocean acidification affects both the biology of the calcification process and the "mineralogy" and "crystallography" of the deposited calcium carbonate, but as the authors are trying to understand the calcification process in foraminifera, we would like to emphasize the importance of the biological process. In foraminifera, the effects of ocean acidification have been one of the hottest topics among the biogeoscience community, and many studies have been reported. However, the response varies according to species, crystal structure (i.e., hyaline and miliolid), and presence or absence of symbionts. Furthermore, both the chemical composition of the test and the process of calcification should be significantly influenced by physiology. Enzymes are responsible for a large part of the physiological activity of foraminifera. In particular, there is still a limited understanding of which enzymes promote calcification, how they are involuted, and whether their function is inhibited. This study aims to confirm that the target enzymes are in the calcification by laboratory experiments with the addition of enzyme inhibitors and observing the shell formation. Acetozaramide and Bafilomycin were added as inhibitors to the carbonic anhydrase, and proton pump, respectively, which have been strongly suggested to be involved in shell formation by previous studies. Our laboratory experiments were conducted with Ammonia sp. to observe the influence on the morphology of the external surface of the test.
Separating eddy driven and subtropical jets in reanalyses
Authors: Spensberger Clemens , Li Camille , Spengler Thomas
Published: March 2022

The distinction between eddy-driven and subtropical jets is conceptually important and well-founded through different driving mechanisms and dominant types of variability. Despite this clear conceptual distinction between the jet types, it is not straightforward to distinguish between these jet archetypes in reanalysis data of individually detected jets.

Inspired by EOF and cluster analyses exploring the variablity between different jets, we here propose a novel and easy-to-apply criterion to distinguish between subtropical and eddy-driven jets. We document that for most ocean basins and seasons, there is a clear bimodality in the occurrence of jets in a potential temperature/wind speed space. These two jet modes in this phase space align well with the conceptual expectations for subtropical and eddy-driven jets regarding their vertical structure as well as their regional and seasonal occurrence.

Surprisingly, the bimodality in phase space is most pronounced in regions such as the western North Pacific during winter, where jets are typically regarded as “merged”, a mixture of eddy-driven and subtropical. Our results thus call into question this typical intepretation of the Pacific jet, and rather suggest that the Pacific winter jet becomes more “merged” in character towards the eastern end of the storm track.
Improvement of rainfall estimates using opportunistic sensors - the example of the flood in Rhineland-Palatinate in July 2021
Authors: Eisele Micha , Bárdossy András , Chwala Christian , Demuth Norbert , El Hachem Abbas , Graf Maximilian , Kunstmann Harald , Seidel Jochen
Published: March 2022

Abstract

Precipitation is highly variable in space and time. Ground-based precipitation gauging networks such as those from national weather services are often not able to capture this variability. Weather radars have the potential to capture the spatio-temporal characteristics of rainfall fields but they also suffer from specific errors such as attenuation. The increasing number and availability of opportunistic sensors (OS), such as commercial microwave links (CML) and personal weather stations (PWS), provides new opportunities to improve rainfall estimates based on ground observations.

We have developed a geostatistical interpolation method that allows a combination of different opportunistic sensors and their specific features and geometric properties, e.g., point and line information. In addition, the uncertainty of the different data sets can be considered [1].

The flood event in the western provinces of Germany in July 2021 showed that both, the precipitation interpolations based on rain gauge data from the German National Weather Service and radar-based precipitation products, underestimated precipitation. We show that the additional information of OS data can improve precipitation estimates in terms of areal precipitation amounts and spatial distribution.  

 

References
[1] Graf, M., El Hachem, A., Eisele, M., Seidel, J., Chwala, C., Kunstmann, H. and Bárdossy, A.: Rainfall estimates from opportunistic sensors in Germany across spatio-temporal scales, https://doi.org/10.1016/j.ejrh.2021.100883
Comparison between Distributed Acoustic Sensing (DAS) and strain meter measurements at the Black Forest Observatory
Authors: Azzola Jérôme , Toularoud Nasim Karamzadeh , Gaucher Emmanuel , Forbriger Thomas , Widmer-Schnidrig Rudolf , Bögelspacher Felix , Frietsch Michael , Rietbrock Andeas
Published: March 2022

We present an original DAS measurement station, equipped with the Febus A1-R interrogator, which has been deployed at the Black Forest Observatory (Schiltach, Germany). The objective of this deployment is twofold. The first is to test the deployed fibre optic cables and to better characterise the recorded signals. The second is to define standards for the processing of these DAS measurements, with a view to using the equipment for passive seismic monitoring in the INSIDE project (supported by the German Federal Ministry for Economic Affairs and Energy, BMWi).

Testing sensors involving new acquisition technologies, such as instruments based on Distributed Fiber Optic Sensing (DFOS), is part of the observatory's goals, in order to assess, to maintain and to improve signal quality. Interestingly, reference geophysical instruments are also deployed on a permanent basis in this low seismic-noise environment. Our analyses thus benefit from the records of the observatory's measuring instruments, in particular a set of three strain meters recording along various azimuths. This configuration enables a unique comparison between strain meter and DAS measurements. In addition, an STS-2 seismometer (part of German Regional Seismic Network, GRSN) allows for additional comparisons.

These instruments provide a basis for a comparative analysis between the DAS records and the measurements of well-calibrated sensing devices (STS-2 sensor, strain meter array). Such a comparison is indeed essential to physically understand the measurements provided by the Febus A1-R interrogator and to characterise the coupling between the ground and the fiber, in various deployment configurations.

We present the experiment where we investigate several Fiber Optic Cable layouts, with currently our most successful setup involving loading a dedicated fiber with sandbags. We discuss different processing approaches, resulting in a considerable improvement of the fit between DAS and strain array acquisitions. The presented comparative analysis is based on the recordings of different earthquakes, including regional and teleseismic events.
Underground workings as a most suitable place for the development of mining technologies - a case study from Polish copper mines
Authors: Fulawka Krzysztof , Mertuszka Piotr , Pytel Witold , Szumny Marcin , Stolecki Lech
Published: March 2022

The current EU policy emphasizes the necessity of the development of more safe and efficient mineral raw exploitation methods. The higher extraction rate and lowest possible environmental footprint of mining activities are the main goals of many international projects. Still, as recent experiences have shown it is challenging to develop new technologies in standard laboratory conditions. This is due to the inability to reproduce the environments present in most of the underground sites. Therefore post-mining underground workings seem to be the most suitable places for the development, validation and testing of new, more efficient mining technologies.

Such activities are continuously performed in KGHM Polish Copper mines, which are the test sites for numerous national and international research projects aimed at improving machinery, monitoring systems, mining methods and safety of work in underground conditions.  

In the present research, the recent experiences of KGHM CUPRUM company in terms of the development of new mining technologies fitted to Polish underground copper mines have been presented.
Quantification of oblique orographic gravity wave propagation deduced from a mountain wave model
Authors: Rhode Sebastian , Preusse Peter , Ern Manfred , Krasauskas Lukas , Geldenhuys Markus , Riese Martin
Published: March 2022

Observations and high resolution models suggest a high potential for gravity waves (GW) to propagate horizontally, which is usually not considered in current parameterizations of general circulation models (GCM). For a quantification of the oblique propagation of orographic GWs and their transport of momentum throughout the atmosphere, we present a mountain wave model (MWM) that describes the terrain induced GW sources, propagation and momentum flux. Being aware of horizontal wind gradients, the model also allows for GW refraction which leads to a turning of the wave vector.

The MWM we present here is a simplified model identifying orographic GW sources from topography data. It is similar to the one presented in Bacmeister et.al. (1994). First, the topography is smoothed using a Gaussian bandpass filter, which allows to consider the different scales of generated MWs separately. This smoothed topography is afterwards reduced to the inherent ridge structure (i.e. to the arêtes of mountains) by employing edge and line detection algorithms from computer vision. Using this underlying arête structure in combination with a fit of idealized Gaussian-shaped mountain ridges to the topography gives us a straightforward way of determining MW parameters for launching a ray, i.e. source location, orientation and size of the wave vector as well as the displacement amplitude. These parameters are then used to calculate the propagation in space and time in given atmospheric backgrounds (determined from smoothed ERA5 (European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis 5th Generation) data) with the ray tracer GROGRAT. The results can then be binned in terms of momentum flux and drag or used for a reconstruction of 3D temperature perturbations for a given time.

The MWM presented here has been validated against global satellite data as well as local measurements to a new quality compared to previous studies. The validation has been performed by applying an instrument-specific observational filter to the model data before considering global maps of momentum flux distributions and horizontal cross-sections of temperature perturbations. Comparisons of these to satellite data and limb measurement retrievals respectively will be shown in this presentation.
18O tracer shows diagenetic isotope exchange in biocalcites to be fast, pervasive and species-dependent
Authors: Cisneros-Lazaro Deyanira , Adams Arthur , Guo Jinming , Bernard Sylvain , Baumgartner Lukas P. , Daval Damien , Baronnet Alain , Grauby Olivier , Vennemann Torsten , Stolarski Jarosław , Escrig Stéphane , Meibom Anders
Published: March 2022

Ocean paleotemperatures have been reconstructed for almost the entirety of the Phanerozoic using the oxygen isotope compositions of calcium carbonates formed by marine organisms and preserved in ocean sediments. However, the isotopic composition of these calcitic tests and shells can be substantially altered through diagenetic processes. Here, we used 18O as an isotopic tracer in controlled experiments designed to simulate early diagenesis of modern benthic foraminifera tests to investigate how fluids penetrate into and exchange oxygen isotopes with these biogenic calcites. Initially pristine tests of Ammonia sp., Haynesina germanica, and Amphistegina lessonii were immersed in an 18O-enriched artificial seawater at 90 °C for hours to days. High-resolution SEM images of the tests before and after the experiments were indistinguishable yet the bulk oxygen isotope compositions of reacted tests revealed rapid and species-dependent isotopic exchange with the water. Correlated SEM, TEM and NanoSIMS imaging of 18O intra-test distributions showed that fluid penetration and exchange is ubiquitous yet heterogenous, and is intimately tied to test ultrastructure and associated organic matter. Species level differences in ultrastructure, quantified through image analysis, explained the observed species-dependent rates of isotopic exchange. Consequently, even calcitic skeletons considered texturally pristine for paleo-climatic reconstruction purposes may have experienced substantial isotopic exchange and hence a critical re-examination of the paleo-temperature record is warranted.
Towards deciphering the contribution of permafrost and active layer to summer runoff in a small alpine catchment
Authors: Kraushaar Sabine , Bloethe Jan Henrik
Published: March 2022

High-mountain regions are very sensitive to climatic changes, which is particularly visible in the drastic retreat of Alpine glaciers. Concomitant with retreating glaciers, permafrost degradation affects large parts of high-mountain regions. In recent years, the hydrological significance of permafrost ice has therefore increasingly come into focus. However, surprisingly little is known about the current state and size of water resources in alpine permafrost. Moreover, it remains unknown whether the thawing of permafrost is already making a significant contribution to late summer runoff in alpine catchments.

In this study we combine UAV-derived volumetric change detection with the hydro-chemical analysis of δ18O and δ2H isotope signatures and the radio nuclide 129I in the discharge from the Kaiserberg rock glacier in the Austrian Alps. The combination of these methods allows a direct and indirect quantification of permafrost degradation. Furthermore, the isotopic signatures help to decipher the relative and absolute permafrost contribution to discharge over the summer months.

First results from the analysis of digital elevation models show an average volume loss of several thousand cubic metres per year between 2017 and 2019. In addition, geochemical data on δ18O- and δ2H-isotopes and the radionuclide 129I indicate an increased contribution of meltwater from the permafrost body of the Kaiserberg rock glacier in the summer months, which is dominant on single days in late summer. 
Comparing the transport of pristine and biofouled microplastic particles on rough surfaces 
Authors: Laermanns Hannes , Haas David , Rolf Markus , Steininger Florian , Löder Martin , Bogner Christina
Published: March 2022

Although the occurrence of microplastic particles (MPs) and their impact on different environments have become a widely recognized research topics, their transport mechanisms in terrestrial environments are still understudied. While first research in this field have focused on the abundance of MPs in soils and its vertical distribution, only little is known about the mechanisms of MP transport on sediment and soils surfaces. This might be explained by the challenges of detecting MPs in terrestrial settings.

Therefore, we investigate the surface transport mechanisms and patterns by using fluorescent MP particles that can be tracked by an advanced complementary metal–oxide–semiconductor (CMOS) high-resolution camera. Within this study we used an experimental set-up including a flume box with surfaces of different roughness and several rates of surface discharge. We traced the pathways of environmentally pristine and biofouled fluorescent amorphously shaped Polystyrene (PS) and Polymethyl methacrylate (PMMA) to analyze how polymer type, biofilm, surface roughness and film thickness influence their transport. Subsequently, time series analysis of the images were performed and evaluated using R software. This included the calculation of particle size, estimation of pathways and path lengths. First results suggest a large influence of the water film thickness of the runoff and the surface roughness. 
Atmospheric Rossby Waves as a Link Between North Atlantic Storm Track Variability and Eastern Mediterranean Cyclones
Authors: Sandler Dor , Ziv Baruch , Saaroni Hadas , Rostkier-Edelstein Dorita , Harnik Nili
Published: March 2022

The Mediterranean Basin has several features that enhance cyclonic activity, such as its complex topography and sharp land-sea temperature differences. However, some processes occurring outside the basin can influence its seasonal variability. In this work, we highlight the relationship between the North Atlantic Storm Track (NAST) and cyclones passing through the Eastern Mediterranean (EM). We use Empirical Orthogonal Function (EOF) analysis of upper-level meridional wind variance to inspect monthly NAST regimes and their influence on wintertime flow in the EM.

We find that the higher functions (EOF4-5) show stronger links to the region and specifically, to anomalies in synoptic fields associated with cyclones (upper-level potential vorticity, sea level pressure) and in monthly precipitation. These functions manifest as a pair of orthogonal zonal waves, reminiscent of subseasonal teleconnections that were previously linked to seasonal precipitation extremes in the EM (the South Levant pattern). It is hypothesized that this connection is mainly brought about by large-scale adiabatic advection of PV in the upper levels. Meanwhile, the two leading NAST modes (“pulsing” and latitudinal “shifting”) were found to produce a comparatively smaller effect.

On the daily scale, we investigate the NAST-EM connection through the lens of zonally propagating Rossby wave packets, in both reanalysis and CMIP6 models (which capture the patterns well).
Iron speciation in southern Israel  phosphates: paleoenvironmental implications
Authors: Zweig Irina , Kamyshny Alexey , Teutsch Nadya , Schneider-Mor Aya
Published: March 2022

Phosphorite deposits in southern Israel alternate between low phosphorous pristine phosphorites and high phosphorous reworked phosphorites. Deposition of pristine phosphorites occurs at high productivity and sedimentation rates under suboxic to anoxic conditions, whereas deposition of reworked phosphorites has been attributed to oxidizing conditions at low sedimentation rates during high-energy episodes accompanied by bioturbation. In this study, iron speciation in primary and reworked phosphates was used for investigating paleoenvironmental conditions of the two phosphate facies. Studied phosphates include low iron sections (Zin and Rotem synclines, North Negev) and iron-rich phosphates deposit (Ein-Ofarim, North Arava). Iron speciation in different synclines provides information on diagenetic processes during phosphogenesis and reworking processes.

Pristine phosphorites are associated with substantially higher total iron (FeT) and highly reactive iron (FeHR) contents compared to the reworked phosphorites. On the other hand, the FeHR to FeT ratio is higher in reworked phosphorites. The pyrite Fe (Fepy) fraction to FeHR ratio is diagnostic for non-sulfidic water conditions for all studied phosphorites. The combination of FeHR/FeT and Fepy/FeHR paleoredox proxies points to possibly anoxic to anoxic-ferruginous sedimentary settings for pristine phosphorites while reworked phosphorites seem to be formed under more anoxic conditions. However, this observation opposes the general concept of reworked facies formation under aerated conditions. As ferruginous conditions are implausible, an alternative explanation for the observed iron speciation could be external input (possibly aeolian dust) of iron-rich particles during initial phosphate. During the reworking processes, removal of poorly reactive iron-rich smectites during reworking processes, although both fractions were depleted by up to 90%. Thus, the observed differences in FeHR to FeT ratio between pristine and reworked phosphates were likely caused by physical processes rather than changes in environmental redox conditions.
Towards the establishment of a global COsmic-ray Soil Moisture Observing System
Authors: Rosolem Rafael , Power Daniel , Rico-Ramirez Miguel , Stowell John Patrick , McJannet David , Schrön Martin , Bogena Heye
Published: March 2022

Soil moisture is an important component of the water balance despite accounting for a small volume relative to other hydrological cycle components. With the continuing evolution of land surface and global hydrological models, characterizing soil moisture dynamics at sub-kilometer scales is becoming ever important. To help with that, the cosmic-ray neutron sensing is an established technology that provides estimates of root-zone soil moisture at 200-300m radius. In simple terms, cosmic-ray neutron sensors can estimate root zone soil moisture through an indirect relationship between measured neutrons scattered from the soil and the amount of hydrogen atoms observed in the soil water.

Following its development in the late 2010s and the establishment of the first COsmic-ray Soil Moisture Observing System (COSMOS) network in the USA, a continuing adoption of this technology has been observed over the years, notably with the establishment of other national scale networks in Germany, Australia, and in the UK. As the cosmic-ray neutron sensing technology matures, so does our understanding on how to better isolate the soil moisture signal from other sources of hydrogen within the sensor footprint. However, despite recent improvements in our understanding, continental and global-scale datasets from cosmic-ray stations are still inexistent, partially due to a lack of proper data harmonization. This is simply because distinct networks operate under their own data processing protocols. This poses unwanted limitations to the use of these data by the wider scientific community.

Here, we introduce the initial steps towards the harmonization of cosmic-ray neutron sensors worldwide. The harmonization is performed using the state-of-the-art and recent developed Cosmic-Ray Sensor PYthon data processing tool, applied to publicly available data from more than 200 stations. We highlight examples of applications using this global harmonized dataset in hydrology, agriculture, and environmental sciences; and present an open discussion about challenges and opportunities in potentially establishing a Global COSMOS network.
Annual deformation and sliding in an alpine temperate glacier: observations and implications for ice rheology and seasonal variation
Authors: Roldan Blasco Juan Pedro , Piard Luc , Gilbert Adrien , Gimbert Florent , Vincent Christian , Gagliardini Olivier , Togaibekov Anuar , Walpersdorf Andrea
Published: March 2022

Glacier deformation velocity is typically linked to ice thickness and is very sensitive to parameters of the Glen’s flow law (i.e. rate factor A and flow exponent n). Detailed observations of glacier deformation in the Greenland Ice Sheet (Ryser et al. 2014, Maier et al. 2019, 2021) reveal that the deformation profile close to the bed, where most of the deformation takes place, is not well represented by typical models and is heavily influenced by bed geometry. We present a similar study done on the ablation zone of Argentière Glacier, a temperate glacier in the french Alps. Glacier deformation was observed during 2020 with permanently installed inclinometers that record deformation at high temporal frequency. This data set is complemented with a dense network of GNSS sensors providing surface velocity. Combining the two sets of observations, we are able to reconstruct the deformation profile with depth and the sliding velocity. We show that the Shallow Ice Approximation strongly overestimates shear stress gradients at depth, such that it can lead to a wrong interpretation of deformation profiles. Instead, the use of a three-dimensional full-stokes model enables us to demonstrate that the yearly-averaged deformation profile is poorly sensitive to the flow law exponent n and instead mainly reflects an increase in the  rate factor with depth. We interpret this rate factor increase by an associated increase in water content with depth, as expected from experimental data and field observations (Duval et al., 1977, Vallon et al., 1976). We further show that internal ice deformation also exhibits seasonal variability that is concomitant with and even stronger than surface velocity changes, such that basal sliding actually has to decrease in summer (at least locally) for our observations to be consistent. These results challenge the general view that glacier seasonal variability is mainly due to seasonal variability in sliding velocity. Further work remains to be conducted in order to fully determine the cause for internal deformation seasonality, which may be explained by changes in stress distribution, in water content or to other yet unidentified factors.