bluuebunny/crossref_metadata_2025 huggingface dataset:
Deterministic modelling of seismic waves in the Urgent Computing context: progress towards a short-term assessment of seismic hazard
Authors: Pienkowska Marta , Rodríguez Juan Esteban , de la Puente Josep , Fichtner Andreas
Published: March 2021

Seismic wave propagation is currently computationally prohibitive at high frequencies relevant for earthquake engineering or for civil protection purposes (up to 10 Hz). Developments of computational high-performance computing (HPC) infrastructures, however, will render routine executions of high-frequency simulations possible, enabling new approaches to assess seismic hazard - such as Seismic Urgent Computing (UC) in the immediate aftermath of an earthquake. The high spatial resolution of near-real time synthetic wavefields could complement existing live data records where dense seismic networks are present or provide an alternative to live data in regions with low coverage. However, time to solution for local near-field simulations accounting for frequencies above 1 Hz, as well as availability of substantial computational resources pose significant challenges that are incompatible with the requirements of decision makers. Moreover, the simulations require fine tuning of the parameters, as uncertainties in the underlying velocity model and in earthquake source information translate into uncertainties in final results. Estimating such uncertainties on ground motion proxies is non-trivial from a scientific standpoint, especially for the higher frequencies that remain an uncharted territory. In this talk we wish to address some of these key challenges and present our progress in the design and development of a prototype of a Seismic UC service. In the long run, we hope to demonstrate that deterministic modelling of ground motions can indeed in the future contribute to the short-term assessment of seismic hazard.  
Spatial distribution of water-mobilizable colloids and phosphorus from dam reservoir sediment 
Authors: Nguyen Ngoc Diep , Grybos Malgorzata , Rabiet Marion , Deluchat Véronique
Published: March 2021

The hydrodynamics of dam reservoirs favor the accumulation of phosphorus (P) in bottom sediments since it has a strong affinity for the sedimentary particles. However mechanical disturbance of sediment (resuspension) may release P back to water column. The load of sedimentary P poses a serious ecological problem related to the maintaining of water eutrophication. The aim of this study was to evaluate the potential of sediments, accumulated in Champsanglard reservoir (Central France), to release water-mobilizable colloidal and dissolved P. A sampling campaign was carried out at different locations along the main channel of reservoir from riverine to lacustrine area and characterized by different hydrodynamics. The results showed that colloids are intrinsic component of reservoir sediment and contribute up to 2.3% of sediment mass. Colloidal P attributed up to 6% of total sedimentary P and 80% of water-mobilizable P (fraction < 1 µm). The stock of water-mobilizable colloids and associated P varied according to particle size distribution and was strongly dependent to channel morphology, hydrodynamics and inlet of tributary.

Keywords: Dam reservoir, sedimentary colloids, phosphorus form, spatial variability
Global mapping of volumetric water content at 10, 33 and 1500 kPa using the WoSIS global database
Authors: Turek Maria Eliza , Heuvelink Gerard , Batjes Niels , Poggio Laura
Published: March 2021

Soil water content is a key property for modelling the water balance in hydrological, eco-hydrological and agro-hydrological models. Currently available global maps of soil water retention are mostly based on pedotransfer functions applied to maps of other basic soil properties. We developed global maps of the volumetric water content at 10, 33 and 1500 kPa by direct mapping based on soil water content data derived from the WoSIS Soil Profile Database and covariates describing vegetation, terrain morphology, climate, geology and hydrology using the SoilGrids workflow. The preparation of the input soil data consisted of the verification of available volumetric water content data and conversion of gravimetric to volumetric data using measured and estimated bulk density. In total we had 9609, 41082 and 49224 soil water content observations at 10, 33 and 1500 kPa, respectively, and prepared around 200 covariates as candidate predictors. After covariates selection, model tuning and cross-validation and final model fitting for 3D spatial prediction, results were presented for the globe with uncertainty estimation. The results were also compared to other available global maps of water retention to evaluate differences between direct mapping against other types of approaches. Directly developing global maps of soil water content, with associated uncertainty, is a novel approach for this type of properties, and contributes to improving global soil data availability and quality.
Structural reconstruction, fault parameterization, and slip rate analysis in the northern Adriatic Sea (Italy): implications for the Plio-Pleistocene tectonic activity of long-lived offshore buried thrusts.
Authors: Panara Yuri , Maesano Francesco Emanuele , Amadori Chiara , Fedorik Jakub , Ghielmi Manlio , Toscani Giovanni , Basili Roberto
Published: March 2021

The northern Apennines foredeep is characterized by a Plio-Pleistocene tectonic activity whose driving structures (thrust faults and related anticlines) are always buried by a high amount of syntectonic sediments, both onshore (Po Plain) and offshore (Adriatic Sea), thereby leaving subtle or none apparent signatures in the topo-bathymetry. Compared to the rest of Italy, this area has a relatively moderate earthquake hazard, but historical reports and instrumental recordings testify for significant seismicity. Seismological analyses of recent sizeable earthquakes (e.g., the Mw 6.1, Emilia earthquake in 2012) confirmed that the seismic activity is mainly due to the outermost northern Apennines buried thrusts. In this work, we reconstructed and parameterized the 3D geometry of such buried faults in an offshore sector just south of the Po River delta by interpreting a dense network of 2D seismic reflection profiles. The availability of two regional seismic reflection profiles, coupled with a detailed reconstruction of Plio-Pleistocene horizons, allowed us to restore the deformation cumulated by these thrusts. Our analysis was aimed at (1) establishing the age of inception of the main crustal thrusts, (2) reconstruct the main Plio-Pleistocene tectonic events affecting the study area, and (3) calculate the Plio-Pleistocene slip rates at different time slices and reporting them through probability distribution functions that take into account the uncertainties associated with horizon ages and restoration parameters. Our results show that the Plio-Pleistocene tectonic activity is variably distributed on different thrust faults and decreases exponentially over time after the Gelasian. The analysis performed on the most recent reflectors suggests that a low but not negligible tectonic activity characterizes the main thrusts in the studied region in the last 4-500 ka and hints at a residual activity that may last until the present.
On the use of Mobile-DOAS measurements for air quality satellite validation
Authors: Merlaud Alexis , Tack Frederik , Van Roozendael Michel , Eskes Henk , Douros John
Published: March 2021

The TROPOMI/S5p instrument was launched in October 2017, aiming to measure from space the atmospheric composition for air quality and ozone monitoring. Since 30 April 2018, TROPOMI/S5p routinely delivers NO2 tropospheric VCDs in quasi-real-time. The first comparisons between this operational TROPOMI product and measurements from the ground and aircraft generally show good correlations but also a negative bias over polluted areas. Such a bias is expected from the low spatial resolution of the CTM used in the operational TROPOMI retrieval and several studies reported a better agreement with local measurements of NO2 VCDs when using a higher resolution model for the satellite AMFs, in practice, changing the original TM5-MP for the CAMS Ensemble.

We compare mobile-DOAS measurements with the two aforementioned versions of the TROPOMI retrievals (TM5-MP and CAMS). Our Mobile-DOAS measurements were performed with the BIRA-IASB Mobile-DOAS during 19 clear sky days. We sampled polluted and clean areas during TROPOMI overpasses in Belgium and Germany between June 2018 and September 2020. Beside studying the effect of the CTM model on the comparisons, we investigate the general added-values of such mobile-DOAS measurements for the validation of TROPOMI/S5p and forthcoming missions.
Soil moisture estimation from high-resolution UASs imagery based on machine learning approaches for land cover classification
Authors: Pizzolla Teresa , Dal Sasso Silvano Fortunato , Zhuang Ruodan , Pizarro Alonso , Manfreda Salvatore
Published: March 2021

Soil moisture (SM) is an essential variable in the earth system as it influences water, energy and, carbon fluxes between the land surface and the atmosphere. The SM spatio-temporal variability requires detailed analyses, high-definition optics and fast computing approaches for near real-time SM estimation at different spatial scales. Remote Sensing-based Unmanned Aerial Systems (UASs) represents the actual solution providing low-cost approaches to meet the requirements of spatial, spectral and temporal resolutions [1; 3; 4]. In this context, a proper land use classification is crucial in order to discriminate the behaviors of vegetation and bare soil in such high-resolution imagery. Therefore, high-resolution UASs-based imagery requires a specific images classification approach also considering the illumination conditions. In this work, the land use classification was carried out using a methodology based on a combined machine learning approaches: k-means clustering algorithm for removing shadow pixels from UASs images and, binary classifier for vegetation filtering. This approach led to identifying the bare soil on which SM estimation was computed using the Apparent Thermal Inertia (ATI) method [2]. The estimated SM values were compared with field measurements obtaining a good correlation (R2 = 0.80). The accuracy of the results shows good reliability of the procedure and allows extending the use of UASs also in unclassified areas and ungauged basins, where the monitoring of the SM is very complex.

References

[1] Manfreda, S., McCabe, M.F., Miller, P.E., Lucas, R., Pajuelo Madrigal, V., Mallinis, G., Ben Dor, E., Helman, D., Estes, L., Ciraolo, G., et al. On the Use of Unmanned Aerial Systems for Environmental Monitoring, Remote Sensing, 2018, 10, 641.

[2] Minacapilli, M., Cammalleri, C., Ciraolo, G., D’Asaro, F., Iovino, M., and Maltese, A. Thermal Inertia Modeling for Soil Surface Water Content Estimation: A Laboratory Experiment. Soil. Sci. Soc. Amer. J. 2012, vol.76, n.1, pp. 92–100

[3] Paruta, A., P. Nasta, G. Ciraolo, F. Capodici, S. Manfreda, N. Romano, E. Bendor, Y. Zeng, A. Maltese, S. F. Dal Sasso and R. Zhuang, A geostatistical approach to map near-surface soil moisture through hyper-spatial resolution thermal inertia, IEEE Transactions on Geoscience and Remote Sensing, 2020.

[4] Petropoulos, G.P., A. Maltese, T. N. Carlson, G. Provenzano, A. Pavlides, G. Ciraolo, D. Hristopulos, F. Capodici, C. Chalkias, G. Dardanelli, S. Manfreda, Exploring the use of UAVs with the simplified “triangle” technique for Soil Water Content and Evaporative Fraction retrievals in a Mediterranean setting, International Journal of Remote Sensing, 2020.
Comparing High Frequency Radar radial and total derived observations capability to correct surface currents using Data Assimilation
Authors: Hernandez Lasheras Jaime , Mourre Baptiste , Orfila Alejandro , Santana Alex , Reyes Emma , Tintoré Joaquin
Published: March 2021

High Frequency Radars (HFR) are a mature remote sensing technology which is widely used in ocean observing systems to monitor surface currents in coastal areas.  HFR systems are composed of 2 or more antennas which measure water motion speed along certain bearings, providing radial observations, which are later on postprocessed and mapped to generate orthogonal currents observations (u, v), herein named Totals.

Both Radial and Total observations have been used to correct surface currents through data assimilation in numerous works in the past years, but, in our opinion, there is a lack of studies comparing the performance of both types of data. Here we present a series of experiments evaluating the capabilities of HFR to correct surface currents in the Ibiza Channel using data assimilation. We put special interest in assessing the potentialities of whether using radial or total observations and also their capabilities in a real operational context.

A Lagrangian assessment using a set of 14 surface drifters deployed in the area allows to evaluate the performance of both kinds of observations, showing how the separation distance between drifting buoys and virtual particles is reduced in both cases.
New paleomagnetic results of the earliest Permian dykes in South Mongolia and their implications for the paleogeography of the Eastern CAOB
Authors: Zhang Donghai , Zhao Guochun , Huang Baochun , Zhao Qian , Zhou Hai , Orsoo Enkh-Orshikh
Published: March 2021

Debates of the Permo-Carboniferous paleogeography of the eastern Central Asian Orogenic Belt (CAOB) mainly focus on the existence, extent, and thereby evolutionary history of the Paleo-Asian Ocean (PAO) in this period. South Mongolia locates at a key position that denotes the southernmost margin of the Mongolia block. Here, we present a paleomagnetic study on the earliest Permian dykes near the Khanbogd of South Gobi Province in Mongolia to better constrain the paleo-position of the Mongolia block. Zircon U-Pb dating results of the studied dykes indicate an emplacement age of 299 ± 3 Ma. Magnetites are the dominant magnetic carriers as revealed by the synthesized rock magnetic experiments. A likely primary high coercivity/temperature component was isolated from 66 of 125 samples and displays consistent reverse polarity, which coincides with the Kiaman Reverse Superchron that overlapping the emplacement age of our studied dykes. Accordingly, a ~299 Ma paleomagnetic pole is calculated at λ/φ = −4.1°N/146.3°E (dp = 3.8, dm = 5.8, n = 66). Potential influence from Paleo-Secular Variation (PSV) is excluded following the Deenen et al. (2011) procedure. Our new results present a ~30.9°N paleolatitude for the Mongolia block, which differs from the lower paleolatitude of the North China and Xilinhot blocks as well as the much higher paleolititude of Siberia. Surrounded by these blocks of different paleolatitude, the PAO and Mongol-Okhotsk Ocean both remained wide open at least by the earliest Permian.

Acknowledgments
This research was funded by the Natural Science Foundation of China (NSFC) (41902229, 41730213, 42072264, 41902229, 41972237), China Postdoctoral Science Foundation funded project and Hong Kong RGC GRF (17307918).

References

Deenen, M. H. L. , Langereis, C. G. , Van, H. D. J. J. , & Biggin, A. J. . (2011). Geomagnetic secular variation and the statistics of palaeomagnetic directions. Geophysical Journal International(2), 509-520.
Tectonic stress patterns along the Vrancea subcrustal zone from the inversion of focal mechanisms data
Authors: Craiu Andreea , Craiu Marius , Mihai Mariu , Manea Elena , Marmureanu Alexandru
Published: March 2021

The Vrancea zone is an unique area with both crustal and intermediate-depth seismic activity and constitutes one of the most active seismic area in Europe.  An intense and persistent seismicity is generated between 60 and 180 km depth, within a relic slab sinking nearly vertical in the Earth’s mantle due to the increasing of the stress state within this volume. At intermediate-depths, large magnitude events are frequent, i.e. four earthquakes with moment magnitudes (Mw) >7 occurred in the last century. An unique slab geometry, likely preserved until the present, causes stress localization due to the slab bending and subsequent stress release resulting in large mantle earthquakes in the region.

In this study, we evaluate the current stress field along the Vrancea subcrustal region by computing the fault plane solutions of 422 seismic events since January 2005. The continuous development of the National Seismic Network allows us to constrain the fault plane solutions and subsequently to evaluate the current stress field.

The main style of faulting for Vrancea subcrustal events presents a predominant reverse one, with two main earthquakes categories: the first one with the nodal planes oriented NE-SW parallel with the Carpathian Arc and the second one with the nodal planes oriented NW-SE perpendicular on the Carpathian Arc. The main axis of the moment tensor may indicate a predominant compressional stress field (Tpl>450 Ppl<450). Another characteristic of  the Vrancea subcrustal zone is the tendency of the extension axis T to be almost vertical and the compression axis P being almost horizontal.

The results of stress inversion indicate a dominant reverse faulting style, with an average stress regime index of 2.9. Other tectonic regimes were observed in the present dataset as normal and strike-slip but they are retrieved for a restrained number of events.

The stress patterns obtained from formal stress inversion of focal mechanism solutions reveal many features of the current stress field that were not captured by large-scale numerical models.
Estimating the travel time and the most likely path from the Global Drifter Program
Authors: O'Malley Michael , M. Sykulski Adam , Laso-Jadart Romuald , Madoui Mohammed-Amin
Published: March 2021

We provide a novel method and tool for computing the most likely path taken by drifters between arbitrary fixed locations in the ocean. In addition to this we provide an estimate of the travel time associated with the path. Lagrangian pathways and travel times are of practical value not just in understanding surface currents, but also in modelling the transport of ocean-borne species such as planktonic organisms, and floating debris such as plastics. To demonstrate the capabilities of this method we show emperical results derived from the Global Drifter Program data. We use the drifter data to construct Markov transition matrices and apply Dijkstra's algorithm to find the most likely paths. The novelty is that we apply hexagonal tessellation of the ocean using Uber's H3 index (which we show is far superior to the standard practice of rectangular or lat-lon gridding). Furthermore, we provide techniques for measuring uncertainty by bootstrapping and applying rotations to the hexagonal grid. The methodology is purely data-driven, and requires no simulations of drifter trajectories. The method scales globally and is computationally efficient.
Periodic Fluid-mediated Weakening and Cementation Drives Cyclic Reorganisation of Shallow Basaltic Fault Zones
Authors: Bamberg Bob , Walker Richard , Reichow Marc
Published: March 2021

Faults constitute the major source for mechanical and permeability heterogeneity in basaltic sequences, yet their architecture, and mechanical and physical properties remain poorly understood. These are however critical as basaltic reservoirs are becoming increasingly important for geothermal applications and CO2 storage. Here we present a detailed microstructural- to outcrop-scale characterisation of mature (decametre-hectometre displacement) fault zones in layered basalts, in the Faroe Islands. Outcrop scale structures and fault rock distribution within the fault zone were mapped in the field to build 3D virtual outcrop models, with detailed characterisation of fault rock microstructure and petrology obtained from optical and SE-microscopy.

The fault zones exhibit evidence for cyclic activity controlled by fault internal fluid pressure variation. Deformation mechanisms in the core alternate between shear-compaction, evidenced by foliated cataclasite and gouge development, and dilatation through fluid overpressure, leading to hydrofracture and vein formation. Generally, a decametre-wide damage zone of Riedel faults is centrally transected by the fault core. The fault core is organised around a principal slip surface (PSS) hosted in a decimetre-wide principal slip zone (PSZ). The PSS and PSZ are dominantly composed of (ultra-) cataclasites, while the remaining core comprises anastomosing cataclastic bands bounding lenticular zones of various brecciated fault rocks. Further, PSS-proximal zones show significant late-stage dilatation by hydrothermal breccias or tabular veins with up to decimetre apertures, filled with early syntaxial to blocky zeolite and/or late coarse (≤ 1 cm) blocky calcite. The structures in the fault core are mutually overprinting, evidencing pulsed fault activity and PSS migration. The native plagioclase-pyroxene assemblage of the host rock is almost completely altered to zeolites and red-brown smectites in the fault core and along surrounding damage of mature faults, while lower displacement faults preserve the host rock mineralogy even in gouge. We infer that fluid flow along initial damage promotes alteration and the associated chemical weakening localises strain into a narrow PSZ. Here, fault activity is governed by alternating deformation styles – shear‑compaction and dilatation – suggesting changes in deformation mechanism linked to transient permeability decrease within the PSZ, followed by fluid overpressure and hydrofracture. Overall rock mechanical properties are thus governed by the combined effects of permanent chemical weakening and transient fluid-mediated mechanical weakening, alternating with cementation and healing, and will be explored by direct shear deformation experiments in the future.
Defining Terms for Climate Literacy
Authors: Singer Katie
Published: March 2021

 

To move forward with substantial, constructive actions that reduce overall consumption and emissions, the public, scientists and policymakers need agreement about our terms. Terms like "sustainability," "zero-emissions" and "carbon-neutrality" tend to focus on a device or vehicle's energy use and emissions during operation--and to exclude energy use and emission during extraction, smelting, manufacturing and recycling or discard. What do such exclusions mean for e-vehicles, smartphones and solar panels? How can we encourage learning about and reducing electronics' true costs? Katie Singer will describe the process involved in manufacturing electronic-grade silicon (similar to solar-grade silicon), and propose that every Internet user learn the international supply chain of one substance (of 1000+) in their device. She will also propose ways to counterbalance a digital footprint.
An experimentally-validated framework for interpreting active-DTS measurements conducted in fully saturated porous media
Authors: Simon Nataline , Bour Olivier , Lavenant Nicolas , Porel Gilles , Nauleau Benoît , Pouladi Behzad , Longuevergne Laurent , Crave Alain
Published: March 2021

            Our ability to characterize aquifers, predict contaminant transport and understand biogeochemical reactions occurring in the subsurface directly depends on our ability of characterizing the distribution of groundwater flow. In this context, recently-developed active-Distributed Temperature Sensing (DTS) experiments are particularly promising, offering the possibility to characterize groundwater flows resulting from heterogeneous flow fields. Here, based on theoretical developments and numerical simulations, we propose a general framework for estimating active-DTS measurements, which can be easily applied and takes into account the spatial distribution of the thermal conductivities of sediments.

            Two independent methods for interpreting active-DTS experiments are proposed to estimate both the porous media thermal conductivities and the groundwater fluxes in sediments. These methods rely on the interpretation of the temperature increase measured along a single heated fiber optic (FO) cable and consider heat transfer processes occurring both through the FO cable itself and through the porous media. In order to validate these interpretation methods with independent experimental data, active-DTS measurements were collected under different flow-conditions during laboratory tests in a sandbox. First, the combination of a numerical model with laboratory experiments allowed improving the understanding of the thermal processes controlling the temperature increase. Then, the two complementary and independent interpretation methods providing an estimate of both the thermal conductivity and the groundwater flux were fully validated and the excellent accuracy of groundwater flux estimates (< 5%) was demonstrated.

            Our results suggest that active-DTS experiments allow investigating groundwater fluxes over a large range spanning 1x10-6 to 5x10-2 m/s, depending on the duration of the experiment. The active-DTS method could thus be potentially applied to a very wide range of flow systems since groundwater fluxes can be investigated over more than three orders of magnitude. In the field, the reliable and direct estimation of the distribution of fluxes could replace the measurement of hydraulic conductivity, whose distribution and variability still remains difficult and time consuming to evaluate.
Spatio-Temporal Gaussianization Flows for Extreme Event Detection
Authors: Fernández-Torres Miguel-Ángel , Johnson J. Emmanuel , Piles María , Camps-Valls Gustau
Published: March 2021

Automatic anticipation and detection of extreme events constitute a major challenge in the current context of climate change. Machine learning approaches have excelled in detection of extremes and anomalies in Earth data cubes recently, but are typically both computationally costly and supervised, which hamper their wide adoption. We alternatively present here an unsupervised, efficient, generative approach for extreme event detection, whose performance is illustrated for drought detection in Europe during the severe Russian heat wave in 2010. The core architecture of the model is generic and could naturally be extended to the detection of other kinds of anomalies. First, it computes hierarchical appearance (spatial) and motion (temporal) representations of several informative Essential Climate Variables (ECVs), including soil moisture, land surface temperature, as well as features describing vegetation health. Then, these representations are combined using Gaussianization Flows that yield a spatio-temporal anomaly score. This allows the proposed model not only to detect droughts areas, but also to explain why they were produced, monitoring the individual contributions of each of the ECVs to the indicator at its output.
EUFAR: the European Facility for Airborne Research
Authors: Brown Philip , Gerard Elisabeth
Published: March 2021

Since its creation in 2000, the European Facility for Airborne Research, EUFAR, evolved into the central network for the airborne research community in Europe. From the beginning until 2018, EUFAR has received funding within the different Framework Programmes of the European Commission. In January 2018, EUFAR became an AISBL (international non-profit association under Belgian law) establishing EUFAR as an independent legal structure and ensuring EUFAR’s future.

Via EUFAR Transnational Access, a range of aircraft and instrumentation has been made available to European researchers who do not have access to a suitable research infrastructure in their home country. This has provided both a comprehensive range of atmospheric in-situ measurements together with a variety of remote-sensing instruments and hyperspectral imagers for studies of land or water surfaces, vegetation etc. Examples of successful TA activities will be shown. In order that researchers should continue in future to have access to the most appropriate research aircraft and instrumentation to meet their science objectives independently of EC funding, EUFAR is now working to develop principles of Open Access (OA).

EUFAR supports Expert Working Group meetings to exchange knowledge and promote best practice across the range of activities involved in airborne research. These cover, for example, instrument developments, data processing software and the scientific uses of airborne data. Via its previous EC funding, EUFAR has been able to support training courses for early-career researchers to introduce them to the use of airborne measurements for environmental research. Where possible, new software tools resulting from these activities are provided openly via the EUFAR website. EUFAR also promotes access to its members' data from airborne platforms and instruments and will be working with the AERIS data centre in France to provide a data portal to assist with this.

This presentation will give an overview of EUFAR, its recent achievements and future plans.
Analysis of the interaction between soil and plant components of green infrastructure in urbanized areas: the case of New Moscow.
Authors: Demina Sofiya , Makhinya Ksenia , Vasenev Viacheslav
Published: March 2021

Soils and green spaces are involved in ensuring the sustainable development and functioning of cities, contributing to the reduction of volatile organic substances and fine dust in the air, the formation of a microclimate, optimization of water balance and the preservation of biodiversity, and provide cultural, aesthetic and educational functions and services. The interaction of soil and plant components has a more significant impact on the sustainable development of green infrastructure in the city. The study of these processes is relevant for new urbanized territories, where their properties are primarily influenced by the history of land use. The research is aimed at studying the soil and plant components of 10 parks located in New Moscow with a different history of land use. According to the data obtained from 4 parks (2 formed on the site of arable land and two formed on the site of a forest), the lightest particle size distribution can be noted in parks located at a distance of more than 15 km from Moscow Ring Road (sandy loam and light loam). The difference between soils in parks formed on the site of arable land from forest parks can be observed in color, the number of horizons in the profile, the abundance of anthropogenic inclusions, and a less pronounced structure. Chemical analysis data show the most significant pollution in parks located far from the Moscow Ring Road. For example, in the parks of the 3rd microdistrict of Moskovsky and Butovo, at none of the points is there an excess of the RPC of Ni, Cu, Cd, As, Pb, in contrast to the other two parks. Analysis of the state of tree plantations shows the impact of land-use history on species diversity in recreational areas. So in the parks formed on the site of arable land, decorative growing trees prevail, which do not grow in natural conditions, this territory. And in the forest-park zones, there is a similarity of the species composition because both parks are formed on the site of a mixed forest.
Geochemical and sedimentological responses of Arctic glacial Lake Ilirney, Chukotka (Far East Russia) to palaeoenvironmental change since ~ 51.8 ka BP
Authors: Vyse Stuart , Herzschuh Ulrike , Andreev Andrei , Pestryakova Lyudmila , Diekmann Bernhard , Armitage Simon , Biskaborn Boris
Published: March 2021

Palaeoenvironmental reconstructions with temporal coverages extending beyond Marine Isotope Stage (MIS) three are scarce within the data sparse region of Chukotka, Far East Russia. The objective of this work was to infer palaeoenvironmental variability from a 10.76 m long, radiocarbon and OSL dated sediment core from Lake Ilirney, Chukotka (67°21´N, 168°19´E). We performed acoustic sub-bottom profiling of the lake basin and analysed high-resolution elements (XRF), organic carbon (TC, TN, TOC), grain-size, mineralogy (XRD) and partly also diatoms and pollen from the core. Our results affirm the application of XRF-based sediment-geochemical proxies as effective tracers of palaeoenvironmental variability within arctic lake systems. Our work reveals that a lake formed during MIS 3 from ca. 51.8 ka BP, following an extensive MIS 4 glaciation in the Ilirney valley. Catchment palaeoenvironmental conditions during this time likely remained cold associated with the continued presence of a catchment glacier until ca. 36.2 ka BP. Partial amelioration reflected by increased diatom, catchment vegetation and lake organic productivity and clastic sediment input from mixed sources from ca. 36.2 ka BP potentially resulted in a lake high-stand ~15 m above the present level and may represent evidence of a more productive palaeoenvironment overlapping in timing with the MIS 3 interstadial optimum. A transitional period of deteriorating palaeoenvironmental conditions occurred ca. 30- 27.9 ka BP and was superseded by periglacial-glacial conditions from ca. 27.9 ka BP, during MIS 2. Deglaciation as marked by sediment-geochemical proxies commenced ca. 20.2 ka BP. Our findings are compared with lacustrine, Yedoma and river-bluff records from across Beringia and potentially yield limited support for a marked Younger Dryas cooling in the study area.
Numerical Modeling of Sampling Seafloor Sediments to Study Their Rheological Properties
Authors: Dubinya Nikita , Nachev Victor , Sergey Tikhotskii
Published: March 2021

The work presents the results of applying SIMULIA Abaqus's capabilities to solve problems related to infrastructure development in the development of oil and gas fields on the continental shelf. The primary attention is paid to the stability of the load-bearing structures of infrastructure facilities. When developing oil and gas fields located in the continental shelf, several geomechanical problems not typical for onshore fields arise. First of all, there is a need to construct a detailed model of the mechanical properties of the upper layers of bottom sediments in conditions of limited data on these properties. This limitation of data is caused by the complexity and cost of engineering drilling, which in other conditions provides the necessary information regarding the properties of the upper layers of sediments. Current study describes the proposed set of methods for studying the mechanical properties of the upper layers of bottom sediments using sampling. It is shown that the process of bottom sampling itself makes it possible to estimate the mechanical properties of bottom sediments. Quantitatively, such estimations can be made based on a numerical solution of the contact problem of gravity corer indentation into visco-elastoplastic medium, the specific rheological properties of which are a priori unknown. The possibility of determining the possible values of these properties from the data obtained in the sampling process (the dependence of the acceleration of the contact point on time) is demonstrated in the study with solution of the inverse problem.
The choice of a thermodynamic formulation dramatically affects modelled chemical zoning in minerals
Authors: Tajcmanova Lucie , Podladchikov Yury , Moulas Evangelos
Published: March 2021

Quantifying natural processes that shape our planet is a key to understanding the geological observations. Many phenomena in the Earth are not in thermodynamic equilibrium. Cooling of the Earth, mantle convection, mountain building are examples of dynamic processes that evolve in time and space and are driven by gradients. During those irreversible processes, entropy is produced. In petrology, several thermodynamic approaches have been suggested to quantify systems under chemical and mechanical gradients. Yet, their thermodynamic admissibility has not been investigated in detail. Here, we focus on a fundamental, though not yet unequivocally answered, question: which thermodynamic formulation for petrological systems under gradients is appropriate – mass or molar?  We provide a comparison of both thermodynamic formulations for chemical diffusion flux, applying the positive entropy production principle as a necessary admissibility condition. Furthermore, we show that the inappropriate solution has dramatic consequences for understanding the key processes in petrology, such as chemical diffusion in the presence of stress gradients.
Historical and projected future hydroclimatic risk on seasonal yield in the irrigated rice paddies of Malaysia
Authors: Zulkafli Zed , Raffar Nurfarhana , Abdi Mukhtar Jibril , Jajarmizadeh Amirparsa , Ahmad Shukri Mohamad Shahmi , Muharam Farrah Melissa , Nurulhuda Khairudin , Rehan Balqis Mohamed , Chung Jing Xiang , Liew Juneng , Tangang Fredolin
Published: March 2021

Food security is an increasing threat to rice-consuming nations in the face of a changing climate. In this study, we present a framework for analysing  the historical and projecting the future relationship between climate variability and rice yield in the context of weather index insurance. The case study is the Muda rice granary, the largest rice paddy planting area in Malaysia producing approximately 40% of the national output. First, correlation and linear regression are used to explore the response of seasonal rice yield to various average and extreme precipitation, temperature and streamflow-based indices over a 16 year period between 2001 to 2016.  The highest Pearson correlation (r) and coefficient of determination (R2) values were obtained with June minimum temperature in the dry season, and December maximum 1 day precipitation and  January mean streamflow in the wet season. The results suggest that rice yield is most at risk from the impact of hydroclimatic variability and change during the flowering and maturity stages of crop growth. Next, findings from the statistical analysis are integrated with hydro-crop simulation of the 4,515 km2 catchment area, using a calibrated Soil Water Assessment Tool (SWAT) and bias-corrected Regional Climate Model output from the Coordinated Regional Downscaling Experiment for South East Asia (CORDEX-SEA). The output is finally used to construct projected future risk profiles for rice production in the area. 
 Spatio-temporal characterization of rainfall using an innovative trend and discrete wavelet transformation approaches in Bhakra catchment, India
Authors: Gupta Neha , Chavan Sagar
Published: March 2021

Using a high-resolution daily gridded rainfall data of 0.25° from the Indian Meteorological Department (IMD), the present study investigates the detailed characteristics of rainfall in the Bhakra Catchment from 1901 to 2019. The long term spatial and temporal rainfall variations in Bhakra Catchment are not well explored. The spatial pattern of rainfall regimes in this catchment is identified by estimating index like the precipitation concentration index (PCI) and seasonality index (SI). Extreme rainfall trends on annual and seasonal basis are examined using the innovative trend analysis (ITA) method. Reliability of ITA was assessed by comparing them with widely applied Mann–Kendall (MK) or modified Mann–Kendall (mMK) test results. Furthermore, the change in two halves of rainfall series is estimated using percent bias technique for estimating changes in rainfall. Changes in slopes are estimated by using Sen’s slope estimator (Q). Discrete wavelet transform (DWT) in conjunction with Sequential Mann–Kendall test (SQMK) is employed to find out the dominant periodicity in rainfall patterns. The effectiveness of the graphical method in qualitative analysis can be seen, while DWT is found efficient in identifying periodicity. Both positive and negative trends are detected in annual and seasonal time series over the study area. The outcomes of this study may be helpful in the planning and management of water resources projects in the catchment along with the planning of mitigation measures to alleviate the effects of climate change under extreme rainfall conditions.
Time to re-think agricultural phosphorus modelling for the 2020s  
Authors: Davies Jennifer M. , Janes-Bassett Victoria , Blackwell Martin , Burgess Andrew , Davies Jessica , Haygarth Philip M.
Published: March 2021

Phosphorus (P) is critical to our food production systems with many crop systems dependent on continual inputs to meet yield demands. However, a consequence of the widespread application of P to agricultural soils in the past 60 years has led to concerns about the long-term sustainability of P fertiliser supply and to P being transferred from soil systems to watercourses, causing diffuse pollution. This highlights the multi-scaled and interdisciplinary nature of the past, present and future of P management.  

The aim of this research is to define a starting framework to consider the best ways to develop a model that addresses the contemporary understanding of P processes, integrating the needs of the crop, with biogeochemical and hydrological modelling considerations, going beyond P transfer to the role of P in both food and water challenges.  

So, this review explores some of the current P models and the future opportunities for expanding their representation of P processes in agricultural systems. This goes beyond nesting existing models and reshapes approaches to posing research and modelling questions to achieve P models that cross disciplinary boundaries and have meaning and usability in practice. As part of this contribution, we welcome modellers and P scientists to come forward and help drive this complex issue of P in agriculture. 
The Multi-Pairwise Image Correlation (MPIC) processing chain, an end-to-end online service for ice motion monitoring using optical imagery
Authors: Michea David , Provost Floriane , Malet Jean-Philippe , Doin Marie-Pierre , Lacroix Pascal , Dehecq Amaury , Boissier Enguerran , Pointal Elisabeth , Bally Philippe
Published: March 2021

Documenting ground deformation is important for a range of areas in Earth and environmental sci-
ences (such as earthquake, volcanoes, landslides and glaciers/ice sheets monitoring). In particular
monitoring the deformation of the cryosphere is key to understand its evolution in a context of
global changes, through the creation of long-term ice velocity datasets, but also possibly detect
failure onsets. The availability of optical satellite constellations with a frequent revisit time at medi-
um to high spatial resolution and an open access policy (e.g. Sentinel 2, Landsat 7/8) provides the
potential to contribute to ice monitoring on a global basis. However, this observational capability
also represents a challenge in term of storage capacity and computing resources which together
with the complexity of the tuning of the different parameters, may prevent users from exploiting the
data.

Here we propose a new version of the Multi-Pairwise Image Correlation for OPTical images
(MPIC-OPT) algorithm. The new version of the algorithm offers a complete chain to process optical
images including data download, image pairs creation and advanced analysis of the displacement
field. It offers the choice to compute the ground displacement associated to image pairs with two
correlation techniques (MicMac, developed by IGN; GéFolki developed by ONERA). Finally, the
Time-Series Inversion for Opical image (TIO) algorithm is integrated to provide displacement time
series.

The processing chain is accessible through the Geohazards Exploitation Platform (GEP) in the
framework of the Thematic Exploitation Platform initiative of the European Space Agency and the
runs are performed using the High Performance Computing facility at the A2S/Mesocentre of Uni-
versity of Strasbourg.

We present the results of the chain in various cryospheric areas: the European Alps glaciers
(France, Italy, Switzerland), the Astrolabe ice shelf (Antartica) and the Gangotri glacier (India). We
define some relevant strategies for an operational use of the service for regional monitoring of
land-ice from satellite images. We compare the results of the MPIC-OPT-ICE service to in-situ
dataset and/or results obtained with similar strategies (e.g. GoLive or ITS-LIVE products, etc.). We
discuss the influence of the pair network and the inversion strategy to retrieve short-term to long-
term kinematic regimes.
Variability of the hydrological characteristics of the Eastern Mediterranean over the last decade
Authors: Estournel Claude , Marsaleix Patrick , Ulses Caroline
Published: March 2021

A hydrodynamic simulation is carried out over the entire Mediterranean basin at a resolution of 3 to 4 km and a duration of about 10 years (2011-2020). The results are systematically evaluated using Argo profiles focusing on the spatial distribution of water mass properties along their path, the main mesoscale structures, the mean vertical temperature and salinity profiles by sub-basins as well as their "pseudo temporal evolution" biased by the variability of the spatial and temporal distribution of Argo observations.

The simulation has generally very low mean biases (of the order of 0.01 for salinity) and correlations on the monthly time series reconstructed from the observations, of the order of 0.9 at the scale of the eastern basin, both in surface waters and at 200 m in intermediate waters.

The evolution of salinity over the decade is then analyzed from the simulation. Particular attention is paid to the main basins of water mass formation, the Adriatic, the Levantine basin and the South Aegean Sea. The factors driving this evolution are analyzed in each of these basins. The propagation of the changes from these formation areas to the entire eastern basin is then examined, with a particular focus on the intermediate waters.
Microbial communities in soil macro-aggregates respire less, are more diverse and stable across successional and geographical gradients
Authors: Sun Daquan , Angst Gerrit , Frouz Jan
Published: March 2021

The stability of soil organic carbon is empirically believed to relate to the location of soil microorganisms inside or between aggregates. However, there are knowledge gaps about how micro-niches shape the microbial community composition and activity and how these effects vary between various soils. Here, we investigate fungal and bacterial community structures (composition and biomass), networks, and respiration in individual micro-niches between and inside soil aggregates using seven different chronosequences (both primary and secondary successions covering sites from pioneer stages to well-developed ecosystems) from a maritime climate in Belgium to a more continental climate in Hungary. We show that while the sampling site is the most crucial factor in shaping microbial community structures, soil aggregates are often more important than succession age and vegetation in differentiating major microbial taxa. Soil fractions are also the dominant factor affecting microbial biomass along the individual chronosequences. Specifically, macro-aggregates often have more variable α-diversities and high microbial community stability, accompanied by low microbial respiration rates. Although the other isolated soil fractions have similar microbial diversities as macro-aggregates, they feature unstable microbial communities with a higher respiration rate. The isolated primary particles have more stable bacterial communities in secondary than primary successions. We, thus, provide a mechanism for interpreting the links between soil microsite heterogeneity, microbial community stability, and microbial respiration. 