bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution of the Galileo system to space geodesy and fundamental physics
Authors: Sośnica Krzysztof , Zajdel Radosław , Bury Grzegorz , Kazmierski Kamil , Hadaś Tomasz , Mikoś Marcin , Lackowski Maciej , Strugarek Dariusz
Published: March 2022

Although the full operational capability of the Galileo system has not been officially announced as yet, the European GNSS, Galileo, has already remarkably contributed to geodesy, positioning, navigation, timing, and fundamental physics. Galileo metadata with the details on the satellite construction and surface properties allow for the development of the high-accuracy satellite macro-models and precise orbit determination. Two integrated onboard observation techniques – satellite laser ranging (SLR) and microwave GNSS – allow for the integration of space geodetic techniques and co-location in space. Calibrated satellite and receiver antenna offsets allow for scale realization and scale transfer for the reference frames.

GNSS orbits of superior quality constitute the basis for other geodetic products, such as Earth rotation parameters, station coordinates, geocenter motion, international terrestrial reference frames, tropospheric and ionospheric delays. Moreover, the high-quality orbits and clocks installed on a pair of Galileo satellites launched onto eccentric orbits allow for studying effects emerging from general relativity, both related to the time redshift, as well as to orbital Schwarzschild, Lense-Thirring, and de Sitter effects constituting the essential issues of fundamental physics. Finally, high-quality and frequently-updated broadcast orbits together with very stable clocks onboard Galileo assure the superior accuracy of the real-time positioning when compared to other GNSS.

We discuss the advantages and limitations of the Galileo system in terms of its applicability to geodesy, concentrating on daily and sub-daily Earth rotation parameters – polar motion and length-of-day variability, station coordinates, and geocenter motion. We address the system-specific errors discovered in GPS, GLONASS, and Galileo time series due to different satellite revolution periods, aliasing effects, tidal constituents, and orbit modeling issues. Some orbit modeling issues related, e.g., to thermal effects, remain unresolved, however, their impact may be mitigated by estimating empirical parameters and the combination of laser and microwave observations. The co-location in space onboard Galileo paves new opportunities for the realization of the reference frames tied in space, onboard GNSS satellites. We provide results on the recent developments of precise orbit determination and co-location in space based on integrated SLR and GNSS observations. Eventually, we discuss the latest applications of high-accurate orbits of Galileo satellites in near-circular and eccentric orbits toward the verification of the effects emerging from general relativity.
Introducing WALIS, the World Atlas of Last Interglacial Shorelines Version 1.0
Authors: Rovere Alessio , Ryan Deirdre D. , Vacchi Matteo , Dutton Andrea , Simms Alexander , Murray-Wallace Colin
Published: March 2022

We present Version 1.0 of the World Atlas of Last Interglacial Shorelines (WALIS), a global database containing samples and sea-level proxies dated to Marine Isotope Stage 5 (~70 to 130 ka). The database was built through manuscripts and associated datasets compiled in a Special Issue of the journal Earth System Science data (https://essd.copernicus.org/articles/special_issue1055.html). We collated the single contributions (archived in Zenodo at this link: https://zenodo.org/communities/walis_database/) into an open-access standalone database. Database documentation is available at this link: https://doi.org/10.5281/zenodo.3961544. Version 1.0 of the database contains 4005 sea-level index points and 4390 dated samples connected with several tables containing relevant metadata (e.g., elevation measurement techniques, sea-level datums, and literature references).
Intercepting rain and stormwater using clay-sand liners to maximize irrigation to shallow-rooted plants in desert and arid areas
Authors: Dafalla Muawia
Published: March 2022

 

 

ABSTRACT: Harvesting rain and flood water is a common practice in desert and arid areas. The storage of water is always influenced by hot weather periods where most of the stored water is lost either by evaporation or infiltration of water into very deep aquifers.  Utilizing sand clay liners as barriers for near-surface material can work as an efficient tool for better use of water resources.  In desert areas where groundwater is located at a deep level the cost of retrieving water is high and requires expensive infrastructure and systems. The concept of this study is to create an artificial aquifer enhanced with pumping systems to supply water to shallow-rooted plants in an adjacent zone.  A simplified model consisting of major collection tanks with automatic pumps was used in a project to save irrigation water in the Eastern province of Saudi Arabia. This concept can be expanded to create large deep-seated storage overlain by granular soil to minimize evaporation. Water supply from this aquifer can be transported to nearby fields by gravity if the water level in the aquifer is higher than the planted area or by pumping if water is needed at a higher level. The sand-clay liner can be made up of bentonite of 10% to 15% clay content by dry weight. The work presented in this study includes the characteristics of the material used and the mechanism followed to retain and re-use water multiple times.  5TE Decagon sensors capable of recording moisture content, temperature, and electrical conductivity connected to Em50 data loggers were employed.  Chemical tests and the salinity of water were monitored during the process. Suggested storage geometries are presented for efficient use of the system.

 

 

KEYWORDS: subsurface storage, barriers, sand-clay mixtures, hydraulic conductivity, evaporation.  
Seismic structure of a Tethyan back-arc: transdimensional ambient noise tomography of the Black Sea lithosphere 
Authors: Petrescu Laura , Borleanu Felix , Placinta Anica
Published: March 2022

The Black Sea is the largest European back-arc basin connected to the subduction and final closure of the Tethys ocean. Its origin and type of crust are widely debated, with contrasting views suggesting it is either a relic of Paleotethys or a rifted back-arc basin formed within the thick and cold Precambrian lithosphere. To investigate the structure of this atypical intra-continental basin, we constructed the highest resolution seismic tomography of the region using the latest techniques of probabilistic inversion of ambient noise data recorded at seismic stations around the sea. Our results indicate the presence of thinned continental crust beneath the basin, likely of Precambrian lithospheric origin, thus invalidating the existence of either a relic Paleotethys fragment or younger oceanic crust. Extension and rifting probably exploited pre-existing sutures, but the rheologically strong lithosphere resisted transition to seafloor spreading. Seismic anisotropy shows complex paleo-deformational imprints within the crust and upper mantle related to the closure of Tethys. Extension caused by subduction roll-back generated anisotropic lithospheric fabric parallel to the rifting axis within the thinnest sections of the crust in the western basin. The eastern part developed on a distinct lithospheric domain that preserves paleo-extension anisotropy signatures in the form of lower crustal viscous deformation. Further south, anisotropy orients along the Balkanide-Pontide collisional system that records the final stages of Neotethys closure. Our results place key constraints on the type of deformations that occurred throughout the Tethyan realm, with fundamental implications for the development and evolution of back-arc basins and continental break-up. 
Storm movement effects on the flash flood response of the Kan catchment
Authors: Khosh Bin Ghomash Shahin , Bachmann Daniel , Caviedes-Voullième Daniel , Hinz Christoph
Published: March 2022

Rainfall is a complex, spatial and temporally variated process and one of the core inputs for hydrological and hydrodynamic modelling. Most rainfalls are known to be moving storms with varying directions and velocities. Storm movement is known to be an important influence on runoff generation, both affecting peak discharge and the shape of hydrographs. Therefore, exploring the extent rainfall dynamics affect runoff generation and consequently flooded areas, can be an asset in effective flood risk management.

In this work, we study how storm movement (e.g. characterized by velocity and direction) can affect surface flow generation, water levels and flooded areas within a catchment. Moreover, the influence of rainfall temporal variability in correlation with storm movement is taken into account. This is achieved by means of numerical-based, spatially explicit surface flow simulations using the tool ProMaIDes (2021), a free software for risk-based evaluation of flood risk mitigation measures. The storm events are generated using a microcanonical random cascade model and further on trajected across the catchment area.

The study area is the Kan river catchment located in the province of Tehran (Iran) with a total area of 836 km², which has experienced multiple flooding events in recent years. Due to its semi-arid climate, steep topography with narrow valleys, this area has high potential for flash flood occurrence as a result of high intensity precipitation.

The results of this study show a range of possible magnitudes of influence of rainfall movement on the catchment´s runoff response. The resulting flood maps highlight the importance of rainfall velocity and most importantly the direction of the movement in the estimation of flood events as well as their likelihood in catchment area. Moreover, its shown that the magnitude of influence of storm velocity and direction on discharge  strongly depends on the location within the river network which it is measured.

ProMaIDes (2021): Protection Measures against Inundation Decision support. https://promaides.h2.de
GRACE-derived groundwater storage estimation: Lake/Reservoir storage controls across Canada
Authors: Akl Mohamed , Thomas Brian , Mills Jon
Published: March 2022

Abstract:
Accurate estimation of groundwater storage is hindered by the lack of direct observations of groundwater over space and time. Gravity Recovery and Climate Experiment (GRACE) satellite observes total water storage, thus presenting issues in applying water budget approaches to extract GRACE-derived groundwater storage. This is especially true in regions with complicated hydrology, ranging from numerous small lakes/reservoirs, elevation variation, and changes in active layer thickness in regions with frozen ground. While the objective of many GRACE studies is to disaggregate total water storage budget, to separately estimate groundwater storage changes, the influence of reservoir storage change within a basin is generally ignored. Extraction of groundwater time series from GRACE, using hydrologic and land surface model output, fails to capture storage changes caused by changes in lake and reservoir storage. In significant surface water areas, reservoir storage may alter water storage changes by increasing leakage errors, and offsetting seasonal variability, leading to accumulation of errors in groundwater estimates. Here, we conducted data-driven experiments to understand the spatial influence of lake and reservoirs on GRACE-derived groundwater storage estimation, using independent information of recorded lake/reservoir water level. The study included comparisons with in-situ groundwater observations throughout Canada to validate our GRACE-derived groundwater storage signal. Accounting for reservoir storage combined with GRACE, improved out estimate of GRACE-derived groundwater storage changes for most basins. Identifying what factors did or did not influence goodness of fit will be addressed.

Acknowledgement: The researcher, Mohamed Akl, is funded by a full scholarship from the Ministry of Higher Education of the Arab Republic of Egypt.
Reducing uncertainty in dispersal predictions: validation of particle tracking model with drifter data.
Authors: Demmer Jonathan , Lewis Matthew , Rushton Rowan , Neill Simon
Published: March 2022

Lagrangian Particle Tracking Models (PTMs) have a wide range of applications in the marine environment, from predicting the dispersal of microplastics to larval transport. In two decades computational power have increased exponentially allowing PTMs to move from probabilistic approaches (e.g. advection and random walk) to more deterministic methods (e.g. including animal behaviour and buoyancy).

Validation of hydrodynamic models simulating oceanographic processes has allowed confidence in their accuracy at simulating mean-flow fields (i.e. at the order of tens of metres and minutes). However, methods to validate PTMs appear less developed due the complexity of biophysical process interactions; for example, wind and wave combined impact on surface currents and larvae behaviour such as vertical and horizontal swimming.

Here, we use a novel set of data representing the travel of drifters in the Irish Sea during summer 2021. The experiment aim is to reduce the near surface flow uncertainty influencing particle dispersal (i.e. larvae, microplastics and pollutant). Data were collecting using a range of drifters designs released in coastal, estuarine and offshore locations of a tidally dominate shelf-sea (Irish Sea): 1) variation of  drogue depth between 1m and 5m; 2)  variation of period from tidal cycles to spring-neap cycles; and 3) some with reduced “windage” designs (no drogue and minimal exposure above surface).

The results allowed us to measure the difference of dispersal between PTM created associated to high-resolution 3D hydrodynamic model and data collected. The validation of a deterministic PTM created will be presented, with a discussion of wind and wave impact on surface current flow and uncertainty of the PTM. For example, we find some scales of oceanographic processes that affect transport, such as turbulent eddies and waves, were not resolved - and yet our predictions broadly matched observations.
EXCITE: A European infrastructure to promote electron and X-ray microscopy of Earth materials
Authors: Walter Sylvia , Cnudde Veerle , Plümper Oliver , ter Maat Geertje
Published: March 2022

Understanding earth materials is critical to creating a sustainable, carbon-neutral society. Earth materials control the feasibility of subsurface energy storage, geothermal energy extraction, and are a source of critical elements for future-proof battery technologies. Perturbations to geological systems can also result in hazards, such as human-induced earthquakes. If we want to tackle the current, pressing scientific questions related to sustainable development for a circular economy, there is an urgent need to make multi-scale, multi-dimensional characterisations of earth materials available to a broad spectrum of earth-science disciplines. In addition to the society-relevant topics, the properties of earth materials determine how the Earth workson the most fundamental level.To overcome this challenge, 15 European facilities for electron and X-ray microscopy join forces to establish EXCITE. EXCITE is a Horizon Europe infrastructure project, and enables access to high-end microscopy facilities and to join the knowledge and experience from the different institutions. By doing so, EXCITE will develop community-driven technological imaging advancements that will strengthen and extend the current implementation of leading-edge microscopy for earth-materials research. In particular, the EXCITE strategy is to integrate joint research programmes with networking, training, and trans-national access activities, to enable both academia and industry to answer critical questions in earth-materials science and technology. As such, EXCITE builds a community of highly qualified earth scientists, develops correlative imaging technologies providing access to world-class facilities to particularly new and non-expert users that are often hindered from engaging in problem-solving microscopy of earth-materials.This presentation gives an overview EXCITE, its activities and open calls, and the progress of the first year of the project.
Evidence for a ca 1.86 Ga continental margin in the Baltic Sea region: rock chemistry, U-Pb ages, and Nd and Sr isotopic data 
Authors: Skridlaite Grazina , Siliauskas Laurynas , Whitehouse Martin , Johansson Åke , Rimsa Andrius
Published: March 2022

The concealed basement of the Mid-Lithuanian domain (MLD) is considered to be part of a larger Precambrian unit within the western East European Craton (EEC), the Mid-Baltic belt (MBB), established by Bogdanova et al. (2015). New data on rock chemistry, U-Pb ages, and the Sm-Nd and Rb-Sr isotopic systems allow to subdivide the MLD into distinct parts, discuss their origin and correlate them with similar units on the Swedish side.

The MLD can be subdivided into two parts: NW and SE. The NW MLD magmatic rocks crystallized from 1.86 to 1.83 Ga and were subsequently intruded by 1.81-1.80 Ga granitoids and charnockitoids. The NW MLD samples have SiO2 contents between 48 and 71 wt.% but have similar initial εNd values at -1 to -2, while their initial Sr isotope ratios scatter. Nd isotope data suggest either an enriched mantle source, or a mantle magma that was mixed with older crustal material.

The SE MLD magmatic rocks originated from a slightly depleted mantle source from 1.87 to 1.82 Ga. At 1792±9 Ma, they were intruded by gabbronorites which in turn were crosscut by thin veinlets of microgabbronorite at 1758±11 Ma. The SE MLD rocks have positive εNd (+1 to +3) and undisturbed Rb/Sr systems suggesting mantle-derivation, with the variation in composition (mafic to felsic) due to fractionation rather than crustal contributions.

The SE MLD magmatic series with oceanic island arc affinity correlate well with the ca 1.85 Ga Fröderyd metavolcanics of the Vetlanda-Oskarshamn belt (Salin et al., 2021) in SE Sweden, while the NW MLD rocks are similar to the TIB-0 (1.86-1.85 Ga) Askersund granitoids (cf. Salin et al., 2021) in the southern Bergslagen area. The younger (1.81-1.79 Ga) intrusives in both areas are time-equivalents of the TIB-1 magmatism on the Swedish side. Thus, the MLD as well as its counterparts on the Swedish side of the Baltic Sea, the TIB-0 magmatism in the southern Bergslagen area and the Vetlanda-Oskarshamn belt, may be assigned to the same Mid-Baltic Belt, representing an active, south-facing continental margin established at ca. 1.86 Ga. The shape and outline of the Belt was affected by the Fennoscandia-Sarmatia collision at ca. 1.82-1.80 Ga, the 1.81-1.76 Ga TIB-1 magmatism, as well as by later Mesoproterozoic intraplate magmatism.

Bogdanova, S. et al., 2015. Precambrian Research 259, 5–33.

Salin, E. et al., 2019. Precambrian Research 328, 287–308.

Salin, E. et al., 2021. Precambrian Research 356, 106134
Biological sulfate reduction in deep subseafloor sediment of Guaymas Basin
Authors: Nagakura Toshiki , Schubert Florian , Kallmeyer Jens ,   IODP Exp. 385 Scientists
Published: March 2022

Sulfate reduction is the quantitatively most important process to degrade organic matter in anoxic marine sediment and has been studied intensively in a variety of settings. Guaymas Basin, a young marginal ocean basin, offers the unique opportunity to study sulfate reduction in an environment characterized by organic-rich sediment, high sedimentation rates, and high geothermal gradients (100-958°C km-1). We measured sulfate reduction rates (SRR) in samples of the International Ocean Discovery Program (IODP) Expedition 385 using incubation experiments with radiolabeled 35SO42- carried out at in-situ pressure and temperature. Site U1548C, outside of a circular hydrothermal mound above a hot sill intrusion (Ringvent), has the highest geothermal gradient (958°C km-1) of all eight sampling sites. In near-surface sediment from this site, we measured the highest SRR (387 nmol cm-3 d-1) of all samples from this expedition. At Site U1548C SRR were generally over an order of magnitude higher than at similar depths at other sites. Site U1546D also had a sill intrusion, but it had already reached thermal equilibrium and SRR were in the same range as nearby Site U1545C, which is minimally affected by sills. The wide temperature range found in the stratigraphic section at each drill site leads to major shifts in microbial community composition with very different temperature optima. At the transition between the mesophilic and thermophilic range around 40 to 60°C, sulfate-reducing activity appears to be decreased, particularly in more oligotrophic settings but shows a slight recovery at higher temperatures.
Biotite as a recorder of an exsolved Li-rich volatile phase in upper crustal silicic magma reservoirs
Authors: Ellis Ben , Neukampf Julia , Bachmann Olivier , Harris Chris , Forni Francesca , Magna Tomas , Laurent Oscar , Ulmer Peter
Published: March 2022

The fate of many economically important elements is controlled at the magmatic-hydrothermal transition, where the co-occurrence of melt and magmatic fluid may significantly change partitioning. With increasing usage of batteries across a range of appliances the requirement for lithium (Li) is growing. Despite this, the behaviour of Li in silicic magmatic systems remains poorly known. Here, we illustrate how compositionally unusual biotites from the Bishop and Kos Plateau tuffs may contain a magmatic volatile phase trapped between layers of biotite crystals. These biotite crystals come from pristine volcanic deposits, appear fresh under the binocular microscope and return oxygen isotopic compositions that, taken together with other phases in the same sample, indicate high-temperature equilibrium. Biotite separates show expected XRD specta indicating the absence of other crystalline phases and yet these biotites return low (< 95 wt.%) analytical totals via electron microprobe (EMP) consistent with the presence of considerable amounts of light elements (non-measurable by EMP). Lithium abundances of these biotites are remarkable with values reaching >2,300 ppm with similar results from both spots and line analyses. Lithium isotopic compositions in these biotites are exceptionally light (δ7Li as low as -27.6‰) and large isotopic fractionation between biotite and corresponding bulk samples (Δ7Libt–bulk as low as −37.3‰). Groundmass glasses, melt inclusions and other mineral phases from the Kos and Bishop systems do not support an extremely Li-rich melt prior to eruption. In contrast, biotites from the phonolitic systems of Campi Flegrei and Tenerife do not exhibit such extreme compositions with bioites and melts having approximately equivalent Li contents with Δ7Libt–bulk to a maximum of −10.9‰. We infer this difference in behaviour to the appearance of biotite in alkaline systems occurring prior to the widespread exsolution of a magmatic volatile phase in the magma reservoir. In the rhyolitic suites, biotite crystallises at lower temperatures and so most biotite growth occurs in the presence of an exsolved fluid phase allowing such a fluid to be trapped within the biotites.  

 
Dynamical propagation and growth mechanisms for convectively coupled equatorial Kelvin waves over the Indian Ocean
Authors: Matthews Adrian
Published: March 2022

Convectively coupled equatorial Kelvin waves (CCKWs) are tropical weather systems that can lead to extreme precipitation. A vorticity budget for CCKWs over the Indian Ocean is presented, to identify the basic mechanisms of eastward propagation and growth. The budget is well closed, with a small residual. In the lower troposphere, CCKWs behave like strongly modified theoretical equatorial Kelvin waves. Vortex stretching, from the divergence of the Kelvin wave acting on planetary vorticity (the −f D term), is the sole mechanism by which the vorticity structure of a theoretical Kelvin wave propagates eastward. In the lower and middle troposphere, this term is also the key mechanism for the eastward propagation of CCKWs but, due to subtleties in its structure and phasing linked to a combination of modal structures, it also contributes to growth. Unlike in the theoretical Kelvin wave, other vorticity source terms also play a role in the propagation and growth of CCKWs. In particular, vortex stretching from relative vorticity (the - zeta D term) is the largest source term, and this leads strongly to growth, through interactions between the background and perturbation vorticity and divergence. Horizontal vorticity advection by the background flow contributes to propagation, and also acts to retard the growth of the CCKW. The sum of the source terms in this complex vorticity budget leads to eastward propagation and growth of CCKWs. The structure and vorticity budget of CCKWs in the upper troposphere is quite unlike that of a Kelvin wave, and appears to arise as a forced response to the lower-tropospheric structure.
Estimated effect of the permafrost carbon stability on the zero emissions commitment to climate change
Authors: MacDougall Andrew H.
Published: March 2022

Zero Emissions Commitment (ZEC), the expected change in global temperature following the cessation of anthropogenic greenhouse gas emissions has recently been assessed by the Zero Emissions Commitment Model Intercomparison Project (ZECMIP). ZECMIP concluded that the component of ZEC from CO2 emissions will likely be close to zero in the decades following the cessation of emissions. However, of the 18 Earth system models that participated in ZECMIP only two included a representation of the permafrost carbon feedback to climate change. To better assess the potential impact of permafrost carbon decay on ZEC a series of perturbed parameter experiments were conducted with an Earth system model of intermediate complexity. The experiment suggest that the permafrost carbon cycle feedback will directly add 0.06 [0.02 to 0.14]oC to the benchmark ZEC value assesses 50 years after 1000 PgC of CO2 has been emitted to the atmosphere. An additional 0.04 [0 to 0.06]oC is likely to been added relative to the benchmark ZEC value from the thaw-lag effect unaccounted for in the ZECMIP experiment design. Overall we assess that the permafrost carbon feedback is unlikely to change the assessment that ZEC is close to zero on decadal timescales, however the feedback is expected to become more important over the coming centuries.
LEELA: The Met Offices next generation lightning location system
Authors: Marlton Graeme , Potts Mike , Twelves Sue , Prust Stephen , Stone Ed , O'Sullivan Debbie
Published: March 2022

Lightning location information has a broad range of uses from Nowcasting through to aviation safety. Hence, the Met Office, based in the United Kingdom, has operated Lightning location systems since 1935. Here the Met Office’s next generation VLF lightning location system: Lightning Electromagnetic Emission Location using Arrival time differencing (LEELA) is described. It is set to replace ATDnet, the Met Office’s current operational system in 2022. LEELA features newly designed hardware and processing architecture, with a new novel technique to extract the sferics from the raw VLF data, and new fixing algorithms that improve location accuracy and detection efficiency over that of ATDnet. The night time issues from modal interference that ATDnet suffered from have been mitigated against and the night time performance of LEELA is improved. It will be shown that LEELA can provide lightning information over Europe, Africa, middle east and central America. In addition to this, the new processing architecture means that a near constant stream of VLF data is recorded and archived allowing investigations into sudden Ionospheric disturbances by observing changes in received power from VLF transmitters.
Feasibility of Brassica juncea as a Hyperaccumulator in Phytomining of Cu and Zn
Authors: Grimm Mark
Published: March 2022

Affordable environmentally friendly solutions are essential for the remediation of waste sites globally. 
Phytoremediation is an increasingly popular environmentally friendly method to help remediate waste 
sites and offset costs of waste site remediation. A greenhouse experiment was set up using to determine 
uptake of metallic zinc (Zn) and copper (Cu) solution by known hyperaccumulator Brassica juncea. With
treatments (T)1- 4, having final added soil concentrations of 100, 200, 310, and 330 mg kg -1 elemental Zn 
and Cu respectively. At 8 weeks, samples were harvested, weighed, and measured for atomic emission 
spectrometry (Agilent Technologies 4210 MP-AES). Phytotoxicity was determined based on visual 
observation, biomass, and chlorophyll measurements. The results showed no significant difference 
between the root mass of control, T1, and T2, whereafter T3 and T4 showed a 52.6%, and 73.7% 
decrease in mean root mass. There was no observable significant difference in leaf or stem mass among 
control, T1-T3, though the mean average of leaf mass decreased across all treatments. T4 showed 
significant difference in average leaf mass from control with a 46.1% decrease in average mass. At the 
highest concentration levels, T4 showed a 62.3% decrease in stem mass when compared to the control. 
AES measurements revealed pools of Zn and Cu in root, leaf, and stem material. The highest 
concentrations of Zn and Cu were to be found in the stem material, with highest observed 
concentrations (T4) being 11,700 mg kg-1 of Zn and 3,116 mg kg-1 of Cu. AES measured leaf material also 
showed large pools of both Zn and Cu with highest observed values (T4) being 5,813 mg kg-1
for Zn and 2,901 mg kg-1 for Cu. It can be determined from this experiment that B. juncea shows the ability to grow 
in heightened levels of Zn and Cu, as well as associate excess free Zn and Cu ions into plant tissues. 
Particles in humus leaching solution influence the input–output budget of the major elements
Authors: Marie Dincher
Published: March 2022

This study presents a complete budget of the input/output fluxes of major elements in the humus layer by considering dust inputs and, for the first time, particle output. Indeed, in a context where forest ecosystems usually develop on poor and unfertilised soils, nutrient cycles and input/output balances are key  to determine the sustainability of forests. This is especially true for the humus compartment.

In this study, we studied mulls in beech ecosystems considering two contrasting soil types.  Over a timespan of 7 years  the inputs and outputs of elements, i.e. both particles (dust inputs and particles in the outgoing solution) and solutions, have been quantified.

The concentrations of the elements in the particles output were 3 or 16 times higher than those in dust, because some particles were produced in the humus. The input/output balances  were in equilibrium for K, Na and S in both soils and for P, Si and Mg in one soil. These elements were transported in the humus mainly as a solution or in soluble form in plant tissues. The inputs were higher than the outputs for Ca and Mn in both soils and for P, Si and Mg in one soil, which are the elements found in biominerals. This indicates that other outputs were not taken into account in this budget, such as biomineral  sedimentation or uptake by fungi. In conclusion this study highlights the importance of the humus particles in element cycles.
Estimation of longshore sediment transport: the case of Lithuania
Authors: Sakurova Ilona , Kondrat Vitalijus , Baltranaite Egle , Kelpsaite-Rimkiene Loreta
Published: March 2022

The Baltic Sea is a semi-enclosed sea that connects with the Global ocean through the Danish straits. The Lithuanian coast of the Baltic Sea is a generic type of almost straight, relatively high-energy, actively developing coasts that (1) contain a large amount of finer, mobile sediment, (2) are open to predominating wind and wave directions, and (3) are exposed to waves from a wide range of directions.

The combination of angular wind distribution and coastal geometry is such that the longshore sediment transport caused by waves is, on average, to the north through the entire Curonian Spit and the mainland coast of Lithuania. This predominant sediment flow means that sediment availability or transportation changes in these areas significantly impact the sediment budget north of Klaipeda. While sediment flows along the spit predominantly occur under natural conditions, further sediment transport to Lithuania's mainland coast is obstructed by jetties and breakwaters of Klaipeda Port, out-flowing currents from Klaipeda Strait, dredging of the port entrance channel, and other factors.

Knowledge of the cross-shore distribution of longshore sediment transport in the surf zone is necessary to design and plan groins, jetties, weirs, and pipeline landfalls.

Accurate estimation of the longshore sediment transport distribution helps understand spit development, migration of sediments, natural or artificial, and the development of other coastal morphologic features.
The role of spatial rainfall variability for the emergence of heavy tails in streamflow distributions
Authors: Wang Hsing-Jui , Yang Soohyun , Merz Ralf , Basso Stefano
Published: March 2022

Heavy-tailed probability distributions of streamflow are frequently observed in river basins. In case of right skewed distributions, the larger probability assigned to relatively high flows translates into an unneglectable chance of occurrence of extreme floods in a long-term hydrological response. Although the spatial variability of rainfall has been identified as an impactful driver of flood events, delineating its effects for the emergence of heavy tails of streamflow distributions is still challenging.

In this study we apply a simple stochastic approach to generate spatially various rainfall as the input of a well-established continuous hydrological model. The model embeds the soil water balance in hillslopes, the probability distributions of transit times in the hillslopes of subcatchments, and the response time distribution in channels derived from a geomorphological analysis of the river network. We investigate the role of spatially variable rainfall for the emergence of heavy tails in streamflow distributions by simulating a wide range of spatial rainfall variability in five catchments in Germany, and then put the modelling results into real world context by analyzing historical data in 175 catchments across the whole Germany.

We find that increasing spatial variability of rainfall determines heavier streamflow tails only beyond a certain increase threshold which depends on physiographic features of catchments. Small and elongated catchments are less resilient to increasing spatial rainfall variability, i.e., their streamflow distributions begin to exhibit heavier tails for smaller increments of the spatial variability of rainfall. The distribution of runoff-routing pathway is suggested to be an effective attribute of catchments in this process.
Searching for partial ruptures of repeating earthquakes in Parkfield, California
Authors: Turner Alice , Hawthorne Jessica
Published: March 2022

Repeating earthquakes are thought to represent the repeated rupture of loaded patches surrounded by regions that are slipping aseismically; they provide a natural laboratory to study interactions between seismic and aseismic processes. These events occur less often than one would expect if these earthquakes accommodate all of the long-term slip. Recent crack models using rate-and-state friction (Cattania and Segall, 2019; Chen and Lapusta, 2009 ) suggest a possible explanation: for small events, a larger amount of the slip budget on the patch being taken up by aseismic slip. For larger events where most of the slip budget is seismic, the patch experiences partial ruptures, also leading to the deviation from expected scaling. We aim to test the predictions of this model of repeating ruptures by searching for the proposed partial ruptures. We choose to search using the Northern California earthquakes catalogue, which contains many well-located repeating earthquake sequences. Preliminary results suggest that partial ruptures in the Parkfield region are not common. If preliminary results pass additional tests, it may suggest that partial ruptures do not make up a significant proportion of the slip budget of larger repeating earthquakes in this region. 
The IMFogram: a new time-frequency representation algorithm for nonstationary signals
Authors: Cicone Antonio
Published: March 2022

In this presentation, we introduce the IMFogram method ( pronounced like "infogram" ), which is a new, fast, local, and reliable time-frequency representation (TFR) method for nonstationary signals. This technique is based on the Intrinsic Mode Functions (IMFs) decomposition produced by a decomposition method, like the Empirical Mode Decomposition-based techniques, Iterative Filtering-based algorithms, or any equivalent method developed so far. We present the mathematical properties of the IMFogram, and show the proof that this method is a generalization of the Spectrogram. We conclude the presentation with some applications, as well as a comparison of its performance with other existing TFR techniques.
On the Multi-component Information of DAS for Near-Surface Seismic: A Pilot Field Experiment in the Groningen Area
Authors: Al Hasani Musab , Drijkoningen Guy , Wapenaar Kees
Published: March 2022

In a surface-seismic setting, Distributed Acoustic Sensing (DAS) is still not a widely adopted method for near-surface characterisation, especially for reflection seismic imaging, despite the dense spatial sampling it provides over long distances. This is mainly due to the decreased broadside sensitivity that DAS suffers from when buried horizontally in the ground (that is when the upgoing wavefield (e.g. reflected wavefield) is perpendicular to the optical fibre). This is unlike borehole settings (e.g. zero-offset Vertical Seismic Profiling), where DAS has been widely adopted for many monitoring applications. Advancements in the field, like shaping the fibre to a helix, commonly known as helically wound fibre, allow better sensitivity for the reflections.

The promise of spatially dense seismic data over long distances is an attractive prospect for retrieving the local variations of near-surface properties. This is particularly valuable for areas impacted by induced seismicity, as is the case in the Groningen Province in the north of The Netherlands,  where near-surface properties, mostly composed of clays and peats, play an essential role on the amount of damage on the very near-surface and the structures built on it. Installing fibre-optic cables for passive and active measurements is valuable in this situation. We installed multiple cables containing different fibre configurations of straight and helically wound fibres, buried in a 2-m deep trench. The combination of the different fibre configurations allows us to obtain multi-component information. We observe differences in the amplitude and phase information, suggesting that these differences can be used for separating the different components of the wave motion. We also see that using enhanced backscatter fibres, reflection images can be obtained for the helically wound fibre as well as the straight fibre, despite the decreased broadside sensitivity for the latter.
Local Constraints on the Dark Sector by Future Missions to Uranus and Neptune
Authors: Zwick Lorenz , Soyuer Deniz , Saha Prasenjit
Published: March 2022

Future ice giant missions could be used to constrain the dark sector. Modifications to the third Kepler-law and deviations from the inverse square law of gravity can be tested by observing the extra perihelion precession of Uranus and Neptune, which allows probing the local dark matter density, modified gravity scenarios and Yukawa-like interactions. As of now, the extraprecession measurements of ice giants are done via ephemerides measurements, which have large uncertainties and provide looser constraints with respect to constraints by other planets. Current upper bound on the local dark matter density lies around ρDM ~ 10-20 g/cm3. However, Doppler tracking missions to Uranus and Neptune with radio ranging accuracy of a few meters can improve this upper bound by 2 to 3 orders of magnitude via the extraprecession technique. Moreover, estimates coming from the spacecraft cruise time energy budget could yield an even better estimate than the Doppler ephemerides measurements, potentially providing evidence for dark matter or shedding light on modified gravity scenarios. Therefore, in addition to planetary science, in situ exploration of Uranus and Neptune also carries significance for exploring the local dark sector and probing fundamental physics.
Black crusts as past air pollution archives
Authors: Ropiquet Mathilde , Verney-Carron Aurélie , Chabas Anne
Published: March 2022

Since the Industrial revolution, emissions of pollutant (gas, aerosols) due to human activities increased and modified the composition of the atmosphere, causing air pollution and climate change. However, pollution measurements are relatively recent. In order to know past air pollution and assess its impact on monuments, proxies need to be found and studied.

One of these potential local proxies is black crusts that are a chemical alteration pattern mainly found on limestone or marble monuments. They are forming a dark mineralogical layer composed of gypsum (CaSO4.2H2O) that results from the sulfation reaction between the calcite (CaCO3) of the stone and the sulphur dioxide (SO2) from the atmosphere. As gypsum is easily soluble, this pattern particularly affects sheltered area from the rain where particulate matter is trapped and accumulates. Therefore, black crusts act as passive sampler and could be used as an archive of air pollution.

To validate black crusts nomination as a new proxy and to find the best pollution marker, samples were collected at Père Lachaise cemetery on ancient tombs (dated from the 1820’s). A specific protocol was applied to separate strata from each other. Then, multiple analyses were realised using SEM-EDS, ICP-AES, and ICP-MS. The results show a different particulate content as a function of the depth, with different contributions of fly-ash typical of coal and oil combustion. This is confirmed by the chemical analyses as the trace metal concentrations are in agreement with the pollution sources. This study demonstrates that laminar black crusts have an internal stratigraphy that can be crucial to reconstruct past air pollution and provides precious data on pollution sources.
Soil compressive behavior: a global assessment of research outputs
Authors: Chagas Torres Lorena , ten Damme Loraine , Holzknecht Alena , Dietrich Maria , Nemes Attila , Keller Thomas
Published: March 2022

Understanding the compressive behavior of soils is essential for establishing management strategies to reduce the risk of soil compaction. Soil compressive properties such as precompression stress, compression index, and swelling index are used to estimate the stress-strain relationship of soil, i.e., the changes of soil volume as a function of applied stress. However, there is no consensus regarding the influence of basic soil physical properties and conditions, such as soil texture, organic carbon content, clay mineralogy, water content, and bulk density on soil compressive properties. Moreover, soil compressive behavior has been measured following non-standardized methods, for example regarding sample size, loading time, methods to obtain the compressive properties from the stress-strain curve, and stress components and packing state of the soil by which the soil compressive behavior can be expressed. These differences in methodology influence the obtained values of soil compressive properties, make comparisons difficult, and limit our understanding of the soil’s stress-strain relationship. We conducted a comprehensive literature study in search of quantifications of compressive properties of agricultural and forest soils, such as precompression stress, compression index, and swelling index, in peer-reviewed articles from the Web of Science and Scopus databases, which currently includes more than 200 articles. We systematically collected the compressive properties as well as information on the soil, soil conditions, methodologies, and other relevant information for each of the published studies. A large part of data originates from a limited number of laboratories in Brazil, Denmark, Germany, Iran, and Sweden, while other parts of the world are less or not represented. We find large variability in soil mechanical properties, that is associated both with variability in soil texture and land use but also with methodological issues. Initial soil moisture was identified as a key driver of soil mechanical properties. Our database allows compiling, synthesizing, and analyzing the data in favor of a comprehensive establishment of relationships between basic soil physical attributes and compressive properties. At the same time, the database is used to identify knowledge gaps and future directions for studies. These findings help the potential development of pedotransfer functions to improve estimations of the soil response to compaction, and to provide a research agenda for a more unified approach for the study of soil compressive properties.
Investigation of mantle anisotropy in NW Namibia by shear-wave splitting analysis: evidence for large-scale mantle flow and fossil-anisotropy
Authors: komeazi Abolfazl , Rümpker Georg , Kaviani Ayoub
Published: March 2022

Presence of the Etendeka continental flood basalts in northwestern Namibia, at the eastern extension of Walvis Ridge toward the African coast, is taken as evidence for the assumption that this region was affected by the Tristan da Cunha mantle plume during the rifting/break-up process between Africa and South America. Investigation of seismic anisotropy can provide further evidence for the cause-and-effect relationship between mantle flow, lithospheric deformation and surface structures. We investigate seismic anisotropy beneath NW Namibia by splitting analysis of core-refracted teleseismic shear waves (SKS family). The waveform data was obtained from two different GEOFON seismic networks in the region. The XC network with 5 stations, which has been operating for two years since 1998 and 6A network with 40 stations including both land and off-shore (OBS) stations, operated for longer than two years in 2010-2012.

The data was analyzed using the SplitRacer software and the results of joint splitting analysis assuming a one-layer of anisotropy are presented here. The less-noisy waveform data from the land stations provide reliable and consistent measurements. We obtained few reliable measurements from the OBS stations due to higher noise level and ambiguity about the sensor orientation. The majority of our fast directions exhibit an NE-SW direction consistent with the regional trend of seismic anisotropy in western Africa compatible with a model of large-scale mantle flow due to the NE-ward motion of the African plate. In the northern part of the study area, we observe an anti-clockwise rotation of the splitting polarization directions that seems to be caused by the Kaoko belt and the Puros shear zone. Based on the short-scale variation of the splitting parameters in this region, we believe that the cause of the lateral variation in SKS-splitting observation is the shallow lithospheric structure rather than a variation of deep mantle flow. Our results does not show any direct plume related observations in the study region.