bluuebunny/crossref_metadata_2025 huggingface dataset:
European Ground Motion Service: production status and validation
Authors: Solari Lorenzo , Balasis-Levinsen Joanna , Andersen Henrik Steen
Published: February 2023

The European Ground Motion Service (EGMS) allows a wide spectrum of users to access ground motion data over 30 European countries for free, under the Copernicus data policy. The EGMS aims to serve for various applications, of which geohazards are probably the primary target. Also, the Service establishes a baseline for studies dedicated to localised deformation affecting buildings and infrastructure in general.The EGMS is the result of a massive computational effort to process thousands of Sentinel-1 images and derive three levels of products: (a) basic, i.e. line of sight (LOS) velocity maps in ascending and descending orbits referred to a local reference point; (b) calibrated, i.e. LOS velocity maps calibrated with a geodetic reference network and (c) ortho, i.e. components of motion (horizontal and vertical) anchored to the reference geodetic network. The EGMS is implemented under the responsibility of the European Environment Agency in the frame of the Copernicus Programme.The EGMS baseline (2016-2020) and the first annual update (2016-2021) were made available to users in the summer of 2022 and in the first quarter of 2023, respectively. The EGMS products are displayed in the EGMS Explorer (https://egms.land.copernicus.eu/), where users can investigate the data in a 3D web interface, explore the temporal behaviour of ground motion through time series and download one or multiple data tiles. External web map services can be imported in the EGMS Explorer to ease the interpretation of the interferometric measurements.The strategy to update satellite interferometric time series is a hot topic for wide area processing services. So that, one of the goals of this presentation is to show the EGMS update strategy, which should guarantee the best trade-off between the identification of new coherent targets and motion areas and the continuity of the Service in terms of technical implementation and noise level.The expected wide usage of the EGMS products required to setup a validation system that has two goals: verify the usability of the data for the expected range of applications and assess the quality of the products with respect to service requirements. Validation is based on seven activities performed in sixteen different countries and in several validation sites, which are representative for thematic applications (e.g. mining-induced ground motion) in different environments of Europe. To guarantee reproducibility of results, the validation data (e.g. levelling or corner reflectors time series, landslide databases) will be made available to users according to licensing conditions. The results of the validation exercise will be available to users in Q3 2023.
"Power To & By the People": A documentary film on statistical evidence for the contribution of citizen-led initiatives to the energy transition in Europe
Authors: Arghandeh Paudler Heather Jean
Published: February 2023

Often overlooked, citizen-led energy initiatives contribute to the low carbon energy transition in Europe. Under the name of energy communities, these groups have been specifically addressed in two separate EU directives (Directives EU-2018/2001 and EU-2019/944). Their projects have grown to produce, distribute, and consume energy from renewable sources while being governed democratically and benefits accruing locally. Despite this, data collection on the topic and statistical accounting of their impacts have not been undertaken systematically until now. This short documentary film quantifies the aggregate contributions of collective action in pursuit of the sustainable energy transition in Europe, estimating the number of initiatives (10,540), projects (22,830), people involved (2,010,600), installed renewable capacities (7.2-9.9 GW), and investments made (6.2-11.3 billion EUR) for 30 European countries.

The data presented in the video draws on our groundbreaking dataset which is the first systematic data collection to capture the nature and scope of collective citizen-led action in the energy transition for each country in Europe (https://doi.org/10.18710/2CPQHQ). The dataset consists of a broad range of variables to a high degree of granularity, covering both organizations and the individual projects that they manage, e.g., installation of renewable capacities, operation of charging infrastructure for electric vehicles, engagement in energy education and services provision, etc.

The documentary begins with background on energy services and cooperatives, highlighting 10 solutions by citizen action initiatives across Europe addressing various current issues of energy security, sustainability, and the affordable provision of energy services. While many of these initiatives are small in scope, they are of sufficient importance to policymakers as they actively involve people in the transformation. A "Facts & Figures" segment quantifies the aggregate contributions of citizen-led energy initiatives. These aggregate estimates do not suggest that collective action will replace government or commercial action in the short- or medium-term without fundamental alterations to policy and market structures, but the film presents strong evidence for the historical, emerging, and actual importance of citizen-led collective action to the European energy transition. Continued decentralization of energy systems and more stringent decarbonization policies will increase the importance of these actors in the future.
Earth’s energy imbalance trend strengthened by recent aerosol emission reductions
Authors: Hodnebrog Øivind , Myhre Gunnar , Jia Hailing , Quaas Johannes , Jouan Caroline , Forster Piers M.
Published: February 2023

The Earth’s energy imbalance (EEI) is the difference in the net solar radiative flux and outgoing longwave radiative flux at the top-of-atmosphere. It has been shown that the positive EEI trend in the previous two decades is unexplained by internal variability and caused by anthropogenic forcing and response, such as that resulting from anthropogenic CO2 emissions. In this work we apply two state-of-the-art global climate models, the CESM2 and ICON-HAM, forced with observed (evolving) sea-surface temperature fields for the period 2000-2019 and with multiple ensemble members, to explore causes for the positive trend in EEI. Both models are able to reproduce the observed EEI trend from the CERES satellite product relatively well. Sensitivity simulations with aerosol emissions kept constant at year 2000 values indicate a relatively strong influence of recent aerosol emission reductions on the EEI trend. Preliminary results further indicate a considerable effect of using the latest CEDS emission version, as opposed to the CMIP6 CEDS version, on the EEI trend.
A review of key material supply constraints to the future deployment of batteries in energy system modelling
Authors: Hvidsten Tobias Verheugen , Zeyringer Marianne , Benth Fred Espen
Published: February 2023

This paper presents a literature review identifying the issues relating to the supply of battery materials most likely to cause constraints. The efforts to decarbonize the electricity and transport sector cause an increasing demand for batteries. Batteries are deployed as energy storage to facilitate high shares of variable renewable energy and in battery electric vehicles. With this rising deployment, the demand for materials utilized in battery technology follow. Lithium, graphite and cobalt are examples of important battery materials expected to experience immense demand growth. The continued access to these materials is essential to decarbonize the electricity and transport sector, which is crucial to meeting the targets of the Paris Agreement.The increased demand for these materials makes it of importance to consider possible constraints to their availability. This paper investigates issues across disciplines to assess these constraints. Causes to such constraints include: (i) Material scarcity, when a material is utilized to the point where reserves are depleted. (ii) Geopolitical issues, which could cause disruptions in supply of a material if reserves are mainly located in one country or region. (iii) Social issues, such as poor working conditions or the effect of extraction on the local environment and population. The literature review is performed to identify these key issues for the supply of critical materials for battery technology, and identify how each of these might constrain the deployment of batteries in the energy system. The key constraining factor of each battery material is identified, and the degree to which this might constrain the deployment of batteries is assessed.Energy system models are often used to assess how to transition to future net-zero energy systems.  To better address sustainability as well as to account for the feasibility of the transition, material constraints should be implemented in the energy system model. This could also lead to optimized energy system developments showing greater resilience against the risks associated with these constraints. The work will provide a comprehensive overview of the main limiting factor to the supply of materials critical to batteries, and with that form a basis for the implementation of these constraints in energy system models.
Mars Sample Return Rock Sampling: Post-landing Extraction of Solid-core Samples.
Authors: Bridges John , Thiessen Fiona ,   NASA-ESA MSR Rock Sampling Team
Published: February 2023

A NASA-ESA Rock Sampling working group has been set up to determine plans for opening the Mars2020 sample tubes once they are returned to Earth. This team works under the oversight of the Mars Campaign Science Group (MCSG). The rocks sampled so far by the Perseverance Rover comprise igneous rocks like basalt and olivine cumulates that experienced various degrees of secondary water alteration; fluviolacustrine sedimentary rocks that show various levels of induration, and unconsolidated Mars regolith. Two main considerations weigh on the strategy that should be adopted for opening the sample tubes on Earth. These are (1) preservation of textural relationships and layering, and (2) minimizing metal and organic, magnetic contamination.It is anticipated that the mechanical state of each sample, as received in the laboratory on Earth, will be assessed by computed tomography (CT) scanning techniques prior to opening.  The decision on how to open each sample tube can therefore be based on geological data collected by the Mars2020 team, tests done on analogue samples, as well as the penetrative imaging data obtained on Earth during basic characterization.The Rock Sampling Team is considering radial and longitudinal cuts through the Ti alloy tubes but finds that a single approach will not be appropriate for all the various types of rock samples that are expected to be returned.  In the next stage of the MSR Rock Sampling Group’s work we will select appropriate Mars2020 analogues and test the proposed tube cutting protocols.The decision to implement MSR will not be finalized until NASA’s completion of the National Environmental Policy Act (NEPA) process. 
Comparing LRI Steering Mirror and Star Camera Data at Low Frequencies
Authors: Müller Laura , Müller Vitali , Misfeldt Malte , Heinzel Gerhard
Published: February 2023

GRACE Follow On measures the Earth's gravitational field by recording distance variations between two satellites flying behind each other around the planet. The attitude and orbit  control system ensures that nominal attitude variations do not exceed a magnitude of a few 100 urad in yaw and pitch. Star cameras and fibre optic gyroscopes measure the inter-satellite pointing angles and indicate when an attitude correction needs to be performed.The Laser Ranging Interferometer (LRI), which was designed as a technology demonstrator but will be implemented as the main science instrument in future missions, measures the distance changes in parallel to the microwave system. However, to maximize the interferometric contrast in the LRI, even when the satellite attitude jitters, a precise pointing between transmitted and received laser beam is necessary and achieved by a two-axes Fast Steering Mirror (FSM).  The FSM measurements provide essentially information about the satellite pointing angles pitch and yaw w.r.t. the line-of-sight connecting both satellites. That allows to compare the FSM to the different attitude sensors like star cameras.We are particularly interested in the characterization of FSM at low-frequencies, i.e. long-term stability of the FSM readout under temperature changes induced for instance by the varying geometry of orbital plane and Sun. We will present recent results on how to model the differences between the star camera and the FSM pointing angles and show analysis results,  which of the instruments might cause the variations in the residuals.Our results are of relevance for future missions, as these missions might employ the LRI FSM as an attitude sensors in order to control the satellite attitude.
Multi-annual variability of a new proxy-constrained modeled AMOC from 1450-1780 CE
Authors: Samakinwa Eric , Riable Christoph , Hand Ralf , Friedman Andrew , Brönnimann Stefan
Published: February 2023

The ongoing discussion about the AMOC slowdown over the 21st century requires a detailed understanding of preindustrial AMOC variability. Here, we present a surface nudging technique to reconstruct the AMOC variability during the Little Ice Age from 1450–1780 CE. The AMOC reconstruction is based on a 10-member ensemble ocean model simulation nudged to proxy-reconstructed sea surface temperature. This approach validates and improves existing knowledge of the AMOC variability, showing that the AMOC slowdown under stable atmospheric CO2 conditions is mainly driven by a 4 to 7 year lagged effect of surface heat flux associated with the North Atlantic Oscillation.
Impact of interannual chaotic variability on the total interannual variability of the North Atlantic Eighteen Degree Water
Authors: Narinc Olivier , Penduff Thierry , Maze Guillaume , Leroux Stéphanie , Molines Jean-Marc
Published: February 2023

Using ensemble ocean simulations, recent studies have shown that non-linear intrinsic oceanic processes are a source of chaotic intrinsic oceanic variability (CIOV). It was found that in eddy-active regions and at interannual timescales, this CIOV can be a significant fraction of total variability, and that as model resolution increases small-scale non-linearities can generate variability at large scales. The Eighteen Degree Water (EDW) is a mode water formed in the winter mixed layer within and south of the Gulf Stream. It is the most abundant T,S class of water in the surface North Atlantic and has been shown to be an important contributor to air-sea exchanges over the entire North Atlantic basin. Observational studies have shown that a significant part of the interannual variability of EDW cannot be explained by atmospheric variability. This motivates the present investigation of the importance of interannual CIOV in the total interannual EDW variability. The present study uses a NEMO-core, 1/4°, 50-member ensemble hindcast of the North Atlantic ocean with a realistic atmospheric forcing. This ensemble simulation is assessed using ARMOR3D, a 3-dimensional gridded observational product obtained using satellite altimetry and ARGO floats. In both datasets, the 3-dimensional structure of EDW is identified using physical criteria. This spatial structure is used to compute timeseries of the EDW’s total volume and average temperature, in each ensemble member and in the observational product. It is found that the ensemble simulation produces a realistic EDW, with a comparable total variability. In the ensemble simulation, the CIOV of integrated EDW properties is estimated from their time-averaged ensemble standard deviation, and is compared to the total variability estimated from the ensemble mean of the temporal standard deviations of all members. In the ensemble, CIOV accounts for 13% of the total interannual variability of EDW volume, and 44% of the total interannual variability of EDW temperature. Notably, this means that CIOV is a source of unquantifiable uncertainty in single-member ocean simulations. This suggests that a significant part of observed interannual variability may also be chaotic intrinsic in nature. This calls for a better parametrisation of chaotic variability in ocean simulations.
Potential Impact of climate Change on Cropland Suitability in Africa using CMIP6 Models
Authors: Egbebiyi Temitope Samuel , Lennard Christopher , Izidine Pinto , Mukwenha Phillip , Wiolski Piotr , Quagraine Kwesi Akumenyi , Ogunniyi Jumoke Esther
Published: February 2023

Future changes in the climate are projected to significantly affect the agricultural sector, notably agricultural production which include cropland suitability. The present study examines the impact of climate change on crop suitability and planting season in Africa under the new Shared Socio-economic Pathways (SSPs). Using the multi-model ensemble climate simulation datasets from the CMIP6 simulations under different SSPs (ssp126, 245, 370 & 585) for the historical (1980-2009), near future (2035-2064) and end of century (2070-2099) study periods. Ecocrop, a crop suitability model was used to investigate the impact of climate change at different SSPs on the suitability and planting season of three crop types, cereals (maize), legumes (Cowpea) and root and tuber (Cassava) over Africa owing to their economic importance to the region. Our findings show all three crops are mainly suitable over most part of Africa with suitability index above 0.5 except south of 20oS in southern Africa and in the Sahel zone (north of 14oN) over the historical period. In general, the impact of climate change leads to about 4% and 7% increase in suitable cropland for Maize and Cowpea respectively relative to the historical period while about 4% suitability decrease is projected for Cassava across the four SSPs. Also, a projected decrease about 1-2% in unsuitable area is projected for the three crops both for near future and end of century relative to the historical period. In addition, no change in planting season is expected across the four SSPs except for a projected 1-2month early planting season for Cassava over West and Central Africa in the near future and end of century and 2-month delay in the planting season for cassava over Congo DR by the end of century under carbon emission with no adaptation (ssp585). The study will assist to improve our understanding on the impact climate change under different SSPs on agricultural production in Africa. It will also help inform policy maker in their decision making of adaptation strategies to ensure food security and zero hunger in sub-Saharan Africa.Keywords : Cropland suitability, Ecocrop, Africa, climate chnage, planting season, CMIP6  
EPOS-Norway Portal
Authors: Michálek Jan , Atakan Kuvvet , Ottemøller Lars , Natvik Øyvind , Langeland Tor , Lampe Ove Daae , Fonnes Gro , Cook Jeremy , Christensen Jon Magnus , Baadshaug Ulf , Kierulf Halfdan Pascal , Grøtan Bjørn Ove , Dehls John , Olesen Odleiv , Maupin Valerie
Published: February 2023

The European Plate Observing System (EPOS) is a European project about building a pan-European infrastructure for accessing solid Earth science data, governed now by EPOS ERIC (European Research Infrastructure Consortium). The EPOS-Norway project (EPOS-N; RCN-Infrastructure Programme - Project no. 245763) is a Norwegian project funded by National Research Council. The aim of the Norwegian EPOS e‑infrastructure is to integrate data from the seismological and geodetic networks, as well as the data from the geological and geophysical data repositories. Among the six EPOS-N project partners, four institutions are providing data – University of Bergen (UIB), - Norwegian Mapping Authority (NMA), Geological Survey of Norway (NGU) and NORSAR.In this contribution, we present the EPOS-Norway Portal as an online, open access, interactive tool, allowing visual analysis of multidimensional data. It supports maps and 2D plots with linked visualizations. Currently access is provided to more than 300 datasets (18 web services, 288 map layers and 14 static datasets) from four subdomains of Earth science in Norway. New datasets are planned to be integrated in the future. EPOS-N Portal can access remote datasets via web services like FDSNWS for seismological data and OGC services for geological and geophysical data (e.g. WMS). Standalone datasets are available through preloaded data files. Users can also simply add another WMS server or upload their own dataset for visualization and comparison with other datasets. This portal provides unique way (first of its kind in Norway) for exploration of various geoscientific datasets in one common interface. One of the key aspects is quick simultaneous visual inspection of data from various disciplines and test of scientific or geohazard related hypothesis. One of such examples can be spatio-temporal correlation of earthquakes (1980 until now) with existing critical infrastructures (e.g. pipelines), geological structures, submarine landslides or unstable slopes. The EPOS-N Portal is implemented by adapting Enlighten-web, a server-client program developed by NORCE. Enlighten-web facilitates interactive visual analysis of large multidimensional data sets, and supports interactive mapping of millions of points. The Enlighten-web client runs inside a web browser. An important element in the Enlighten-web functionality is brushing and linking, which is useful for exploring complex data sets to discover correlations and interesting properties hidden in the data. The views are linked to each other, so that highlighting a subset in one view automatically leads to the corresponding subsets being highlighted in all other linked views.
200 000 years of glacially induced faulting in the Tornquist Fan area, SW Baltic Sea.
Authors: Seidel Elisabeth , Steffen Holger , Steffen Rebekka , Ahlrichs Niklas , Hübscher Christian
Published: February 2023

We present a comparative study of the glacially induced fault reactivation within the Southern Baltic Sea since the Upper Saalian. A complex tectonic pattern characterizes the Tornquist Fan, which spans between the Tornquist Zone in the North and the Trans European Suture Zone in the South. Multiple fault zones result from the varying transpressional and transtensional stress activities since the Paleozoic. The current tectonic pattern of this unique natural laboratory is composed of several faults with varying strike and dip directions, depths and characters (normal, reverse, strike slip). Moreover, some shallow faults are associated with Zechstein salt pillows, and others are related to anticlines formed during the Cretaceous to Paleogene compression.Using finite-element simulations of different glacial isostatic adjustment models (varying the material parameters in the Earth and the ice history), we obtained glaciation induced Coulomb failure stress changes (∆CFS) at the faults over time, covering the past 200 ka. Comparing the activation potential of several faults of different tectonic background reveals the impact of the varying crustal and fault properties, as well as the influence of salt structures below. Besides lateral differences in the ∆CFS due to the changing geology, we see temporal differences, by comparing the occurrence of glacially induced faulting with different ice advances.
Data preparation for the development of a user-friendly, free, online, and interactive platform for the visualization and analysis of interdisciplinary data
Authors: Linck Rosenhaim Ingrid , Mieruch-Schnülle Sebastian , Schlitzer Reiner
Published: February 2023

The MOSAiC Expedition 2019/20 (https://mosaic-expedition.org) brought together scientists from different research institutes around the globe for a year in the Central Arctic. They collected an incredible amount of data to expand the understanding of the Arctic, its distinct features, and the consequences of a changing climate. Since January 2023, the data collected during the MOSAiC Expedition is available as Open Source in the long-term archive Pangaea (https://pangaea.de) for anyone who would like to learn and study the Arctic Ocean and its features. The M-VRE webODV Project (https://mosaic-vre.org) aims to offer an interactive online exploration, visualization, and analysis of the MOSAiC data in a user-friendly environment. In the M-VRE webODV (https://mvre.webodv.cloud.awi.de), these data are presented as Data Collections that consist of similar datasets aggregated into singular collections and Interdisciplinary Collections, where complementary datasets are aggregated into collections. However, for the MOSAiC data to be explored, visualized, and analyzed with webODV, it has to be converted from the tab file format used in the Pangaea archive to an ODV readable format. Therefore, the data is converted through a six steps process: search, filtering, download of datasets, data aggregation, metadata preparation, and data conversion into the ODV format. Although several datasets after those steps are ready to be uploaded to the M-VRE webODV, other datasets need special and individualized conversions. As a result of the data conversion process and the special conversions, the Data Collections and Interdisciplinary Collections of MOSAiC Expedition data are uploaded to the M-VRE webODV and available for user exploration, visualization, and analysis. The M-VRE webODV is since January 2023 open to the global community, and the number of available Collections is increasing.*MOSAiC – Multidisciplinary drifting Observatory for the Study of Arctic Climate*M-VRE webODV – MOSAiC Virtual Research Environment web Ocean Data View
Influence of evapotranspiration formulation on long-term trends (1980-2022) of the Adige river basin hydrological water budget.
Authors: Bouabdelli Senna , Morlot Martin , Massari Christian , Formetta Giuseppe
Published: February 2023

The Adige river basin (~11000 square kilometers) is the second longest in Italy and affects the population living in the Trentino-Alto Adige and Veneto region. It is an example of hydrological complex river basin because it includes high anthropization causing intensive and often conflicting water uses, presence of seasonal snow cover with runoff delayed from snow falling season to late Spring and Summer, glaciers, and irrigated areas, which are important for food production of the region.In this work, we model the hydrological cycle of the Adige river basin over the period 1980-2022, investigating the effect of three evapotranspiration formulations on the long term trends of each hydrological compartments, i.e. soil moisture, groundwater storage, and river runoff. The modeling part is implemented by exploiting the potential of the open-source, semi-distributed, component-based hydrological modeling system GEOframe modeling system, which is applied at daily time-step and at a high spatial resolution (<5 km²).The model, together with the different evapotranspiration formulations, has been validated against river runoff and satellite retrieved soil moisture data. Results, which have been analyzed also in the context of the 2022 drought which hit Northern Italy, show that increasing the complexity of the evapotranspiration formulation improved model performances for all the simulated hydrological components.
The Power of Many: Utilizing Citizen Science Data in Species Distribution Models to Forecast Urban Avian Biodiversity in the Metropolis Ruhr, Germany
Authors: Bührs Malte , Schmitt Thomas
Published: February 2023

In the last couple of years, the Citizen Science (CS) approach became more reliable, generating a huge amount of environmental data (‘Big Data’) considering the help of volunteers and amateur researchers. In the same time, Remote Sensing capabilities and resolutions improved significantly. Especially in urban environments such as the Ruhr Metropolis, where private lands and high diverse landscapes are predominant and large concentrations of people as potential volunteers are available, combining CS data and Remote Sensing techniques with the predictive power of Species Distribution Models can play an important role to comprehensively investigate and evaluate avian biodiversity representing keystone species in urban ecosystems. However, spatially modeled habitat suitability for multiple avian species in dense and fragmented urban environments are still lacking.An ensemble of different machine learning algorithms, CS datasets of multiple avian species expected to react differently to urban conditions and environmental predictors consisting of bioclimatic variables, digital surface models and land use derived information were applied to forecast avian biodiversity patterns and distributions. These comprehensive predictions of habitat suitability enable policymakers to make sophisticated decisions in landscape planning and conservation taking into consideration present and future land use changes due to urban densification and urban sprawl, especially within the context of an ongoing historical unique transformation process in the Metropolis Ruhr.
Evidence of Synorogenic Extension in the Upper-Middle Crust in Central Taiwan
Authors: Lozano Blanco Olivia , Lund Björn , Ayarza Puy , Álvarez-Marrón Joaquina , Brown Dennis , Wu Yih-Min
Published: February 2023

The active Taiwan mountain belt is located in a complex geodynamic setting that involves two subduction processes. To the northeast, the Philippine Sea Plate subducts northward beneath the Eurasian Plate at the Ryukyu Trench, while in the southwestern part, the Eurasian Plate subducts eastward under the Philippine Sea Plate, where it obliquely collides with the Luzon Volcanic Arc. The Taiwan thrust-and-fold belt is created as a result of this ongoing arc-continent collision. Regardless of the predominance of compression in the overall structure of the island, several studies have also reported normal faulting. This study aims to estimate the local and regional stress field using earthquake focal mechanism data to contribute to a better understanding of crustal deformation in the complex tectonic setting of Taiwan.Manually clustered earthquake focal mechanisms are inverted to obtain an estimate of the principal stress (σ1, σ2, σ3) orientations and the stress ratio (σ1-σ2)/(σ1-σ3), from which the direction of the maximum horizontal stress (SH) is calculated. The initial data set contains 11,587 earthquake focal mechanisms compiled from several sources dating between 1990 and 2020. All deep earthquakes in the Ryukyu subduction zone were removed from the data set. The Chi-Chi 1999 and other major earthquakes and aftershocks were also removed as they may reflect a distorted stress field. After preprocessing, a database consisting of 8,510 events with focal depths between 1-144 km and magnitudes ML=0.7-5.9 was used in the inversion. Depth division was performed in a regular 7 km grid up to 28 km depth, all events deeper than 28 km being considered in the same layer.Preliminary results show that, to the southwest, the notable clockwise rotation of SH from SW-NE to a W-E direction and a change in the fault type from strike-slip to reverse to the east coincides with the interaction between the ENE-striking reactivated inherited structures of the Eurasian continental margin and the NNE-striking thrust faults of the foreland thrust-and-fold belt. To the centre-east, results show normal faulting in the upper crust, which changes to reverse faulting with depth, suggesting that there is a stress transition at approximately 14 km. Beneath that depth, there is a general state of compression. Ongoing research aims at integrating these results with those of numerical modelling and with field data in an effort to understand the locus of deformation and the occurrence of extensional tectonics in compressional settings, here and in other mountains belts worldwide.This research is part of project PGC2018-094227-B-I00 funded by the Spanish Research Agency of the Ministry of Science and Innovation of Spain. Olivia Lozano acknowledges funding from the same agency through contract PRE2019-091431. Funding from SERA European Union H2020 INFRAIA-2016-2017 Agreement, 170522 is also acknowledged. 
A novel source-free frequency-domain full waveform inversion
Authors: Yang Qingjie , Engsig Marcus , Geng Meixia , Kasmi Chaouki
Published: February 2023

Full waveform inversion (FWI) is a challenging data-fitting procedure based on full wavefields to abstract quantitative information from seismograms. During the process, the wave propagation equation is solved for different sources and frequencies. Therefore, an efficient and effective wave propagation engine plays a critical role for FWI. The modelled data, theoretically, can be seen as the composites of Green’s function and source wavelet, convolution in the time domain, or multiplication in the frequency domain. So, the accurate source wavelet is essential for successfully applying full waveform inversion on a real dataset.  Yet, it remains a challenging task for data sets with sparse acquisition and noisy field datasets. In the traditional inversion procedure, the source signal can be estimated from observed seismograms as a part of FWI, which is time consuming and may result in inversion divergence. A source wavelet can also be extracted from the direct arrivals in the streamer dataset. However, the quality of the direct arrivals can be diminished by reflections and near-surface noise for land acquisition, vertical seismic profiling (VSP), and ocean bottom cable (OBC) datasets.To avoid inaccurate source wavelet estimation, various source-independent methods are applied to FWI. Firstly, the deconvolution-based source-independent algorithm is proposed to mitigate the uncertainty of source wavelet estimation by normalizing the seismic data with a reference trace in the frequency domain. Then, the convolution-based source-independent algorithm is presented in the time domain to eliminate the source wavelet influence by convolving the observed data with a reference trace selected from a modelled wavefield, and the modelled data with a reference trace selected from an observed wavefield. To avoid an arbitrary or manual selection of the reference trace, we present a convolution-based source-free method implemented in the frequency domain. Thus, the convolution process becomes a multiplication in our source-free misfit function, achieving a significantly simpler implementation than in the time domain and requiring no artificial interposition.
Soil phosphorus prediction by visNIR could be dependent on the conversional P determination method
Authors: Asrat Tadesse Gashaw , Haefele Stephan M , Sakrabani Ruben , Hassall Kirsty L , Kebede Fassil , Breure Timo , Corstanje Ron
Published: February 2023

Proximal soil spectroscopy can be useful to estimate relevant soil properties in real time and cheaply for agricultural decision support and soil health monitoring. However, prediction performance of plant available soil phosphorus by the visNIR has been unsatisfactory as it is considered among the least spectrally active soil properties. Hence, we compared prediction performance among plant available soil phosphorus (Olsen P), extractable soil phosphorus (ammonium-oxalate extract of P - AmOxP), total soil phosphorus (Aqua regia extract of P - TP) and phosphorus buffer index (PBI) using visNIR soil spectral sensing instrumentations (Neospectra and Fieldspec-4) using East African agricultural soils. The comparison was made by scanning 360 archived soil samples which were collected from 0-20cm soil depth in Ethiopia, Kenya and Tanzania. The spectra data was pre-treated with SavitskyGolay smoothing + first derivative and a PLSR was used to develop the predictive models from a 75% of the dataset (#270) subsampled by a conditioned Latin Hypercubic sampling (cLHS) method using the spectra space. The model performance was evaluated by an independent set of samples (#90) by calculating the concordance correlation coefficient (CCC), ratio of performance to interquartile range (RPIQ), bias and root mean square error of prediction (RMSEP).  The most important wavelengths for all soil P indicators in the NIR instrument ranged between 2150 -2400 nm whereas it included 500-570 nm for the visNIR instrument. PBI was predicted with higher CCC value of 0.94 and 0.89 for visNIR and NIR, respectively, however it has the least RPIQ (0.4 and 0.3, respectively) values when compared to other soil P prediction by both instruments. TP and AmOxP were predicted with higher accuracy and model consistency when compared to OlsenP and PBI. The visNIR range gave better prediction accuracy and model consistency for all soil P indicators than the NIR range. Hence, our findings indicated that TP and AmOxP could be preferred to predict soil phosphorus status for any agricultural and soil health monitoring using soil spectroscopic techniques.Keywords: proximal soil spectroscopy, PLSR model, Savitzky-Golay smoothing filter, first derivative, Neospectra, Fieldspec-4, East Africa.
Exploration of the lunar deep interior through global deformation modeling.
Authors: Briaud Arthur , Ganino Clément , Fienga Agnès , Rambaux Nicolas , Mémin Anthony , Hussmann Hauke , Stark Alexander , Hu Xyanyu
Published: February 2023

The Moon is the most well-known extraterrestrial planetary body thanks to observations from ground-based, space-borne instruments and lunar surface missions. Data from Lunar Laser Ranging (LLR), magnetic, gravity, surface observations and seismic Apollo ground stations help us to quantify the deformation undergone by the Moon due to body tides. These observations provide one of the most significant constraints that can be employed to unravel the deep interior. The Moon deforms in response to tidal forcing exerted by, to first order, the Earth, the Sun and, to a lesser extent, by other planetary bodies. We use the degree-2 tidal Love number as a tool for studying the inner structure of our satellite. Based on measurements of the tidal Love numbers k2 and h2 and quality factors from the GRAIL mission, LLR and Laser Altimetry on board the LRO spacecraft, we perform a random walk Monte Carlo samplings for combinations of thicknesses and viscosities for models of Moon with and without inner core. By comparing predicted and observed parameters of the lunar tidal deformations, we infer constraints on the outer core viscosity, for a Moon with a thin outer core and a thick inner core, and a Moon with a thicker outer core but a denser and thinner inner core. In addition, by deducing the temperature and assuming the chemical composition of the low-viscosity zone, we obtain stringent constraints on its radius, viscosity and density. 
Collapse of Late Permian chert factories in the equatorial Tethys and the nature of the Early Triassic chert gap
Authors: Yang Fen , Sun Yadong , Frings Patrick , Luo Lin , Eh Jingwen , Wang Lina , Huang Yafei , Wang Tan , Müller Johann , Xie Shucheng
Published: February 2023

The Permian witnessed the extensive development of cherts from the palaeoequator to the northern high latitudes. However, large-scale chert deposition was abruptly terminated in the latest Permian, resulting in the Early Triassic "chert gap". Deepwater sedimentary successions in South China across the Permian-Triassic transition recorded the shift from radiolarian- and spicule-bearing siliceous units to carbonate/siliciclastic facies in the equatorial Tethys. In order to constrain the onset time of the chert production crisis and understand its nature, we carried out sedimentological, palaeontological, and geochemical analyses on two deepwater sections along the northern margin of the South China Block. Our results suggest that chert production in equatorial latitudes was already weakened in the Clarkina changxingensis conodont zone. The final collapse of the chert factory occurred in the Clarkina yini - Hindeodus praeparvus/Clarkina zhangi Zone and was accompanied by a significant decrease in SiO2 content, which predated the negative carbonate carbon isotope excursion and climate warming but coincided with a sharp decline in primary productivity. Combined with Si box model results, our study suggests that global warming cannot maintain a multi-million-year chert gap. Instead, the loss of siliceous skeleton producers was the primary cause of the Early Triassic chert demise.
The onset of a large gravitational slope deformation on Mt. Svínafellsfjall, SE Iceland.
Authors: Ben-Yehoshua Daniel , Sæmundsson Þorsteinn , Hermanns Reginald L. , Erlingsson Sigurður , Helgason Jón Kristinn , Magnússon Eyjólfur , Ófeigsson Benedikt
Published: February 2023

Since the end of the Little Ice Age in the late 19th century Iceland’s glaciers have experienced dramatic mass loss. Thinning outlet glaciers are exposing oversteepened rock slopes, which sometimes adjust in the form of slow slope deformations that can occasionally result in catastrophic paraglacial rock slope failures. Especially around the country’s deglaciating central volcanoes large landslides have occurred in the past decades. We describe a cluster of gravitational mass movements around the margin of the Svínafellsjökull outlet glacier in Southeast Iceland. The glacier margin is a popular tourist attraction with hundreds of visitors daily. Housing, a hotel, a gas station and the national ring-road are located within one kilometer downstream from the glacier. The largest deformation in the valley is located on the northern slope of Mt. Svínafellsfjall and is evidenced by a 2-km-long fracture system that separates an area of about 1km2 and a rock volume in the range of 50-150x106m3 from the mountain slope. The unstable slope is characterized by about elongated 200 sinkholes where soil cover has collapsed into underlying bedrock fractures. In several places across the slope, deep vertical bedrock fractures with no visible vertical displacement were observed. Based on morphological and structural mapping we suggest that the deformation occurs as a composite slide. Remote sensing data, eyewitnesses and field observations indicate that the onset of the deformation occurred between 2003 and 2007. This is parallel with the fastest glacier thinning rate within the 131-year record of existing data. Since 2011 the glacier surface hasn’t lowered significantly, in part due to the deposits of a large debris avalanche from 2013 on the glacial tongue which protect the glacier against ablation. The slope hasn’t shown new signs of deformation since 2018. It is however likely that the slope deformation will start again when glacier thinning continues. Even though deformation rates have been small it is crucial to continue monitoring the slope since several large rock slope failures in Iceland have shown only a short pre-failure deformation period. In a worst-case scenario a catastrophic landslide could travel across the glacier and enter two pro-glacial lakes which may lead to an outburst flood. This study shows how climate change driven glacier thinning has and likely will have further destabilizing effects on paraglacial slopes in Iceland and similar environments elsewhere.
A seasonal calibration approach of conceptual hydrological models for improved real-time river forecasting
Authors: Nossent Jiri , Nsubuga Ronald
Published: February 2023

Conceptual hydrological models can play an important role in real-time river forecasting systems due to their limited calculation time and versatility. Nevertheless, their simplified structure, very often based on the water content in multiple storages, and constrained physical background hampers their applicability in seasonally influenced catchments. In particular, these models often show good forecasting performance in one season (e.g. for high discharges in wet seasons), but fail to capture events in other seasons (e.g. due to typical high intensity precipitation during dry periods). To overcome this issue, we propose a seasonal calibration approach for conceptual hydrological models, based on the results of a seasonal sensitivity analysis. The obtained seasonal models however induce an additional challenge within a continuous real-time river forecasting system: the transition from one seasonal model to another. The latter is of particular importance when the volume of the storages in the conceptual model changes between different seasons. An application with the conceptual NAM model for three catchments in Belgium will be used to illustrate the proposed calibration strategy and a number of possible solutions for the transition issue.
Optimization of deficit irrigation through monitoring the plant and soil water status in adult lemon trees
Authors: Temnani Abdelmalek , Pérez-López Raúl , Berríos Pablo , Fioretti Giorgio , Zapata-García Susana , Pérez-Pastor Alejandro
Published: February 2023

Agriculture located in arid-conditions is under high pressure for water resources, due to scarcity and poor quality of water resources to a large extent. Under these conditions, this sector may need up to 70% of the available water, and there is a high level of competition with other economic sectors. The Region of Murcia (Spain) is one of the main productive areas of the country and has the largest irrigated area in relation to its extension. The SE Spain is characterized by a robust hydraulic infrastructure, efficient irrigation systems and a high incorporation of technology for irrigation scheduling. Also, a significant decrease in water resources due to climate change is projected, so it is necessary to maximize irrigation water use efficiency (iWUE) to ensure the economic and environmental sustainability of the sector. Therefore, the main objective of the study was to increase the iWUE and nutrient use to maximize the sustainability of the lemon trees ‘Fino 95’ (Citrus limon L.) in Campo de Cartagena by monitoring the plant and soil water status, during two consecutive seasons. The orchard was established in a 6.5 × 4.5 m planting frame in 2010 with a drip irrigation. A randomized experimental design was established with 12 trees as an experimental unit. Two treatments with four replicates were tested: (i) a control (CTL) irrigated to satisfy the 110% of the crop evapotranspiration (ETc) during the entire crop cycle according to FAO; and (ii) a precision irrigation treatment (PI), irrigated in both seasons as CTL until the start of the fruit-phase II in which the irrigation was reduced by 40%. Several multispectral vegetation indices over canopy were calculated monthly to evaluate the irrigation effect on chlorophyll content and crop vigor. NDVI ranged from 0.8-0.87 and CGI from 4.3-8.7, both reaching maximum values in December, but no differences between treatments were detected. The results confirm the possibility of applying regulated deficit irrigation strategies on lemon trees, achieving a 34% increase in iWUE, and a water saving of around 25% with respect to the CTL treatment. However, the water deficit period should be better delimited according to the trunk growth in this period, as has recently been proven in other citrus fruits, in order not to affect the earliness of the harvest and to obtain a higher percentage of irrigation water savings.Acknowledgments: The authors would like to thank the ‘Sindicato Central de Regantes del Acueducto Tajo-Segura’ for funding this experiment through the agreement “6217/20IA-C” with the UPCT.