bluuebunny/crossref_metadata_2025 huggingface dataset:
How repeated use of urease and nitrification inhibitors affect soil microbes and N2O emissions in North China Plain? 
Authors: Zhang Wei , Liu Rui , Meng Fanqiao
Published: March 2021

A common approach to reduce N loss is inclusion of inhibitors with the fertilizer formulation. However, the performance of commercially available inhibitors is often highly unpredictable, with efficacies lasting for few weeks or even only days, for reasons that are still poorly understood. Furthermore, how repeated use of these inhibitors affect soil microbes and nitrogen (N) transformation remains elusive. In the current study, we investigated the response of the community compositions of critical N-cycling biomarkers involved in nitrification and denitrification (including amoA, nxrA, nxrB, narG, nosZ), potential nitrification rates (PNR) and N2O emissions to repeated addition of urease and nitrification inhibitors (nBPT, DMPP) based on a 4-year field experiment. The results demonstrated that 4 years of fertilization significantly affected the community structure of nitrifiers, except AOA. Repeated addition of inhibitors significantly reduced N2O emissions (P ˂ 0.05) and changed the community structure of bacterial-amoA, nxrB, narG and nosZ compared to urea application alone (P ˂ 0.05), but the effects of DMPP and nBPT on N2O emissions and soil microbes were different. Inhibitors had no significant effect on the soil PNR and archaeral-amoA and nxrA. Based on structural equation modeling, amendment with the inhibitors reduced N2O emissions through directly affecting NH4+-N substrate availability for soil microbes and subsequently changing community composition of AOB. These findings help to disentangle the interplay of nBPT and DMPP with soil microbes and N2O emissions in North China Plain.
Dense Glacial Termini Time Series Analysis: Insights from Calving Front Machine (CALFIN)
Authors: Cheng Daniel , Larour Eric , Hayes Wayne
Published: March 2021

Sea level contributions from the Greenland Ice Sheet are influenced by the rapid changes in glacial terminus positions. While manual delineation is labor intensive, recent developments in the field of automated calving front extraction have allowed for high spatio-temporal resolution analysis of Greenlandic glaciers. Specifically, we analyze new developments and results from the Calving Front Machine (CALFIN). CALFIN uses machine learning in the form of deep neural networks to automatically generate 25,000+ calving front positions from 1972 to 2020 across 80+ Greenlandic basins, using Landsat and Sentinel-1 imagery. With this data, we perform a correlative analysis between area changes, centerline length changes, discharge, thickness, bed topography, and temperature, among others. Trends on the local and regional scales are examined for insights in conjunction with existing studies in the field. Ultimately, the current implementation offers a new opportunity to explore trends on the extent of Greenland's margins, and supplies new constraints for simulations of the evolution of the mass balance of the Greenland Ice Sheet and its contributions to future sea level rise. We welcome any critiques, suggestions, or questions regarding the dataset and/or our methods. This work was conducted as a collaboration between NASA’s Jet Propulsion Laboratory and the University of California, Irvine.
Modelling the disastrous Flash Flood of November 2017 in Mandra (Attica, Greece)  
Authors: Tsokanis Konstantinos , Mitsopoulos George , Bloutsos Aristides , Stamou Anastasios I.
Published: March 2021

The region of Attica is characterized by a relatively large number of floods over a long period of time. The flash flood in Mandra on the 15th of November 2017 was the third most disastrous “November” flood in Attica; most of the population was affected by the flood (23 deaths and 24 people injured), while basements and ground floors of buildings in the town were seriously impacted.

The two main streams that pass through the town of Mandra are Soures and Agia Aikaterini, whose catchment area is equal to 23.0 and 22.0 km2, respectively. These streams are characterized by significant morphological changes due to the intensive construction activities in the greater area that resulted in a dramatic decrease of their available cross-sectional areas and the occurrence of floods even at low flow rates.

We applied the HEC-RAS 1D/2D to model the flash flood using a high resolution Digital Surface Model (DSM) and topographic survey data, to obtain the most accurate representation of the area of Mandra. Moreover, we imported to the model all technical works, such as culverts and bridges that affect the flow. For the model calibration, we employed (a) videos, photographs, information from the local population and satellite images to determine the inundation area and (b) in situ measurements of the flood water depth, in various locations within the town of Mandra. The results of the model were compared with calculations performed within a previous Thesis in 2018 using TELEMAC-2D.

The present paper is based on the Master Thesis of the first author; it was performed within the project “National Network on Climate Change and its Impacts (CLIMPACT)” of the General Secretariat of Research and Technology.
Tethys Belt in the Anatolia-Caucasus-Black Sea Region: Basins, Magmatic Arcs, Ophiolites, and LIPs
Authors: Teknik Vahid , Artemieva Irina , Thybo Hans
Published: March 2021

We interpret the paleotectonic evolution and structure in the Tethyan belt by analyzing magnetic data sensitive to the presence of iron-rich minerals in oceanic fragments and mafic intrusions, hidden beneath sedimentary sequences or overprinted by younger tectono-magmatic events. By comparing the depth to magnetic basement (DMB) as a proxy for sedimentary thickness with average crustal magnetic susceptibility (ACMS), we conclude:

 (1) Major ocean and platform basins have DMB >10 km. Trapped ocean relics may be present below Central Anatolian micro-basins with DMB at 6-8 km and high ACSM.  In intra-orogenic basins, we identify magmatic material within the sedimentary cover by significantly smaller DMB than depth to seismic basement.

(2) Known magmatic arcs (Pontides and Urima-Dokhtar) have high-intensity heterogeneous ACMS. We identify a 450 km-long buried (DMB >6 km) magmatic arc or trapped oceanic crust along the western margin of the Kirşehır massif from a strong ACMS anomaly. Large, partially buried magmatic bodies form the Caucasus LIP at the Transcaucasus and Lesser Caucasus and in NW Iran.

(3) Terranes of Gondwana affinity in the Arabian plate, S Anatolia and SW Iran have low-intensity homogenous ACMS.

(4) Local poor correlation between known ophiolites and ACMS anomalies indicate a small volume of presently magnetized material in the Tethyan ophiolites, which we explain by demagnetization during recent magmatism.

(5) ACMS anomalies are weak at tectonic boundaries and faults. However, the Cyprus subduction zone has a strong magnetic signature which extends ca. 500 km into the Arabian plate.
Optimal sensor placement method for wastewater treatment plants based on discrete multi-objective state transition algorithm
Authors: Li Wenting , Yang Chunhua , Han Jie , Zhang Fengxue , Lan Lijuan , Li Yonggang
Published: March 2021

Municipal wastewater treatment plants (WWTPs) reuse domestic sewage, industrial wastewater, and rainfall runoff to realize sustainable utilization of fresh water resources. In order to guarantee the safety, reliability, and profitability of the WWTP, efficient process monitoring and control is becoming increasingly important. However, due to the economic and technical requirements, it is infeasible to place sensors at every process parameter location. Therefore, it is necessary to design the optimal sensor placement scheme which leads to maximum information gain about the plant conditions. Practical issues present in the WWTP, such as harsh physical conditions, fluctuation of water quantity, and variability in process parameters, make the optimal sensor placement problem an especially complicated one. Furthermore, sensors placement problem contains multiple objectives with complex nonlinear relationship. This study focuses on obtaining the optimal flow sensor placement scheme of the WWTP in terms of cost, information richness and redundancy. First, based on the graph theory and structural observability and redundancy criteria, a WWTP system model is constructed. Next, an industrial condition weighting factor setting strategy is introduced to measure the importance of the variables in different processing units, transforming the optimal flow sensor placement problem in the whole process into a discrete multi-objective optimization problem. Then, a novel metaheuristic method named discrete multi-objective state transition algorithm (DMOSTA) is proposed to obtain optimal trade-off solution set. Finally, an evaluation strategy is applied to select the best flow sensor placement scheme from the solution set. The proposed method is applied to three WWTPs with different dimensions. Comparative results show that the optimal flow sensor placement scheme based on the proposed method has the best comprehensive performance in regard to senor cost, process variable observability, sensor redundancy, and computational cost.
High quality monitoring dataset needed for improving VOC emission knowledge in a Mediterranean port city 
Authors: Dufresne Marvin , Salameh Thérèse , Léonardis Thierry , Gille Grégory , Lanzi Ludovic , Armengaud Alexandre , Sauvage Stéphane
Published: March 2021

Volatile Organic Compounds (VOCs) play a key role in the atmospheric pollution, especially as they are precursors of secondary pollutants (ozone, secondary organic aerosols, etc.), and they are key tracers of many sources.. Previous studies in the Mediterranean region, which is a hotspot of air pollution and climate change, have shown a high organic pollution due to VOCs. Moreover, in the Western part of the Mediterranean, few studies have been conducted regarding VOCs despite frequent ozone pollution episodes still occurring especially in Marseille-France. Long-term high quality VOC datasets are therefore crucial for the evaluation of emission inventories used as inputs of the chemical-transport models. The objective of our work is to improve our knowledge regarding VOC source apportionment in Marseille with a focus on emissions related to shipping raising the need of high quality monitoring datasets. For the first time, a one year and half (March 2019 - August 2020) measurement campaign has been conducted in Marseille at an urban area representative site receiving air masses from the harbor. In addition to a large set of instruments, two on-line thermal-desorption gas chromatography flame ionization detector have been used for the continuous hourly measurement of 70 Non-Methane HydroCarbons (NMHCs) from 2 to 16 carbon atoms covering alkanes including IVOCs, alkenes, alkynes, aromatics. Here, we will focus on the metrological aspects of the analytical instruments (traceability, repeatability, etc.), intercomparison of common species measured with both instruments, as well as an intercomparison of several calibration methods developed for IVOC (C10 to C16) measurement. A special attention has been given to the uncertainty estimation following ACTRIS and WMO guidelines.  Finally, we will show an overview of the Positive Matrix Factorization (PMF) model results, applied to a necessarily large robust dataset of observations with the associated uncertainties.
Hydro-Mechanical Modeling of the Year 2000 Hydraulic Stimulation of GPK2 Well, Soultz-sous-Forêts, France
Authors: Javani Dariush , Schmittbuhl Jean , Cornet Francois
Published: March 2021

 Hydraulic stimulation of pre-existing fractures and faults plays a significant role in improving hydraulic conductivity of the fracture network around injection and production wells in geothermal reservoirs. It is therefore important to characterize the hydro-mechanical behavior of the faults against fluid injection. The Soultz-sous-Forêts site (France) has been an EGS pilot site where several major hydraulic stimulations have been performed and are well documented (https://cdgp.u-strasbg.fr/ and https://tcs.ah-epos.eu/).

Here we use the 3DEC numerical modeling tool (Itasca) to analyze the year 2000 stimulation of GPK2 well where large scale seismic anomalies have been evidenced during the different stages of the stimulation using 4D-P-wave tomography (Calo et al, 2011). The specificity of the approach is to combine two modeling at different scales. First, a small-scale model (100x100x100 m3) is built to analyze the effective mechanical response of a stochastic discrete fracture network (DFN) following the statistical features of the observed fracture network (Massart et al, 2010). Second, a large-scale numerical model of the Soultz-sous-Forêts reservoir (5000x5000x5000 m3) containing the largest faults of the reservoir defined by Sausse et al., 2010, is developed including regional stresses. The objective is to constrain the large-scale mechanical properties of the surrounding matrix around the fault from the small-scale model, in particular, its hydro-mechanical behavior in terms of non-linear elastic response related to the stochastic DFN. As a first step only the largest fault (GPK3-FZ4770) is considered. The first stage of the stimulation is modelled as a constant flow rate of 30 ls-1 of water injected into the fault at the depth of approximately 4.7 km. We explored the effect of the normal and shear stiffness of the fault on the dynamical response of pore pressure along the fracture and the onset of slip. It is found that the increase of the aperture of the fault during the injection shows a slow migration (~2 cm/s) owing to poro-elastic effects. Also generated fluid pressure throughout the fault shows a long period oscillating behavior (~5 hr) sensitive to the magnitude of the fracture normal stiffness.
Mid-Norwegian continental margin magmatism and Paleogene global climate change: An overview of the upcoming International Ocean Discovery Program (IODP) Expedition 396
Authors: Planke Sverre , Huismans Ritske , Berndt Christian , Gernigon Laurent , Buenz Stefan , Faleide Jan Inge , Jones Morgan T. , Svensen Henrik H. , Jerram Dougal A. , Millett John M. , Myklebust Reidun
Published: March 2021

Continental breakup between Greenland and NW Europe in the Paleogene was associated with transient massive magmatism and a global hot-house named the Paleocene-Eocene Thermal Maximum (PETM). The International Ocean Discovery Program (IODP) Expedition 396 will study the cause of this magmatism and its climate implication by drilling up to nine boreholes across the Vøring and Møre continental margins in August-September 2021. The expeditions will be conducted in conjunction with ICDP project PVOLC which plan to drill the Paleogene sequences in a more distal setting in Denmark in 2022. The NE Atlantic conjugate volcanic rifted margins are characterized by extensive break-up magmatism recorded by basalt flows, volcanogenic sediments, magmatic underplates, and intrusive complexes in sedimentary basins and the crust. Massive injection of magma into organic-rich sedimentary basins is a likely mechanism for triggering short-term global warming during the Paleocene-Eocene Thermal Maximum (PETM). A key objective of this expedition is to document the nature and explain the causes and consequences of excess magmatism during breakup as the large amount of magmatism cannot be easily be explained by passive decompressional melting of sub-lithospheric mantle with a normal potential temperature. New constraints on 1) melting conditions, 2) timing of magmatism, 3) spatial and temporal variations, 4) eruption environment, 5) sedimentary proxy data, and 6) temporal resolution of magmatism and climate change events are required to resolve current controversies. Systematic IODP drilling is a way to provide these constraints and will allow the development of a quantitatively testable framework for volcanic rifted margin formation and consequences for global climate change. New 3D seismic data collected by the industry and academia during the past few years have provided unique imaging of the basalt and sub-basalt sequences and allowed for optimal planning of the drill sites for scientific purposes. Additional holes are located along and outboard of the continent-ocean boundary to constrain the temporal evolution of the breakup magmatism. Two of the scientific drilling aims of this cruise are to core Paleogene sequences across the PETM and to drill one of the thousands of hydrothermal vent complexes to attain a proximal record of NAIP activity. This will give vital information on the proximal environmental disturbances during the NAIP emplacement.
Reconstructing Sea Surface Dynamics Using a Linear Koopman Kalman Filter
Authors: Ouala Said , Fablet Ronan , Pascual Ananda Pascual , Chapron Bertrand , Collard Fabrice , Gaultier Lucile
Published: March 2021

Spatio-temporal interpolation applications are important in the context of ocean surface modeling. Current state-of-the-art techniques typically rely either on optimal interpolation or on model-based approaches which explicitly exploit a dynamical model. While the optimal interpolation suffers from smoothing issues making it unreliable in retrieving fine-scale variability, the selection and parametrization of a dynamical model, when considering model-based data assimilation strategies, remains a complex issue since several trade-offs between the model's complexity and its applicability in sea surface data assimilation need to be carefully addressed. For these reasons, deriving new data assimilation architectures that can perfectly exploit the observations and the current advances in signal processing, modeling and artificial intelligence is crucial.

In this work, we explore new advances in data-driven data assimilation to exploit the classical Kalman filter in the interpolation of spatio-temporal fields. The proposed algorithm is written in an end-to-end differentiable setting in order to allow for the learning of the linear dynamical model from a data assimilation cost. Furthermore, the linear model is formulated on a space of observables, rather than the space of observations, which allows for perfect replication of non-linear dynamics when considering periodic and quasi-periodic limit sets and providing a decent (short-term) forecast of chaotic ones. One of the main advantages of the proposed architecture is its simplicity since it utilises a linear representation coupled with a Kalman filter. Interestingly, our experiments show that exploiting such a linear representation leads to better data assimilation when compared to non-linear filtering techniques, on numerous applications, including the sea level anomaly reconstruction from satellite remote sensing observations.
Co-design and co-deployment of nature based solutions for river flooding mitigation in northern Italy river embankments
Authors: Pulvirenti Beatrice , Ruggieri Paolo , Domeneghetti Alessio , Toth Elena , Alfieri Silvia Maria , Foroughnia Fatemeh , Menenti Massimo
Published: March 2021

Po valley in the Emilia Romagna region, Northern Italy, is threatened by hydro-meteorological hazards, such as river flooding. In the last 50 years this area was interested by an intensive urbanization (with cities that span from the size of a village to metropolitan urban areas such as Bologna) with the realization of infrastructures, e.g. roads and residential settlements near rivers. In addition, the strengthening and expansion of the embankment system led to the development of the areas prone to floods located nearby the rivers. These modifications, in combination with the occurrence of high flood peaks recently experienced in this area have increased the impacts and thus, the attention, on riverine floods. The last event occurred in December 2020, where Panaro river, a tributary of the Po river, broke its banks near Modena causing large flooded area.

Co-design and co-deployment of nature based solutions (NBS) to reduce flooding risk in the Panaro river is one of the objective of the H2020 project OPEn-air laboRAtories for Nature baseD solUtions to Manage environmental risks (OPERANDUM). A portion of the Panaro river embankment is one of the Open Air Laboratories (OAL) where special deep rooted plants were implemented to evidence the mitigation of hydro-meteorological risks by NBS.

In this work, a combined approach between Earth Observation (EO) data and multi-scale modelling is shown, to support the co-design process of the NBS. Synthetic Aperture Radar (SAR) and optical EO data were used to identify areas at risk, i.e. the area most likely to be affected by severe flooding events.  A thresholding method was applied to the SAR and optical images available during past extreme events to identify size and location of the floods. The remote sensing analysis allowed the definition of specific portions of the Panaro river where NBS can be more effective for flood risk reduction. In a second step, a multi-scale modelling approach, based on the characterisation of deep-rooted plants by laboratory experiments and in-field measurements, is used to determine the response of the identified portions of Panaro river to flooding events and to evaluate the effectiveness of possible NBS.

Remote sensing analysis indicates that the area between Secchia and Panaro rivers, delimited to the north by the town of Bomporto and to the South by the town of Albareto has been most frequently inundated in the recent extreme events. The integrated analysis leads to the identification of potential sites, along the Panaro river, where NBS could be effective for river flooding risk reduction, contributing to the definition of the priority sites among the ones defined by the stakeholders and engineers.
Deploying and operating an Absolute Quantum Gravimeter on the summit of Mount Etna volcano
Authors: Carbone Daniele , Antoni-Micollier Laura , Greco Filippo , Lautier-Gaud Jean , Contrafatto Danilo , Ménoret Vincent , Messina Alfio
Published: March 2021

The NEWTON-g project [1] proposes a paradigm shift in terrain gravimetry to overcome the limitations imposed by currently available instrumentation. The project targets the development of an innovative gravity imager and the field-test of the new instrumentation through the deployment at Mount Etna volcano (Italy). The gravity imager consists in an array of MEMS-based relative gravimeters anchored on an Absolute Quantum Gravimeter [2].
The Absolute Quantum Gravimeter (AQG) is an industry-grade gravimeter measuring g with laser-cooled atoms [3]. Within the NEWTON-g project, an enhanced version of the AQG (AQGB03) has been developed, which is able to produce high-quality data against strong volcanic tremor at the installation site.
After reviewing the key principles of the AQG, we present the deployment of the AQGB03 at the Pizzi Deneri (PDN) Volcanological Observatory (North flank of Mt. Etna; 2800 m elevation; 2.5 km from the summit active craters), which was completed in summer 2020. We then show the demonstrated measurement performances of the AQG, in terms of sensitivity and stability. In particular, we report on a reproducible sensitivity to gravity at a level of 1 μGal, even during intense volcanic activity.
We also discuss how the time series acquired by AQGB03 at PDN compares with measurements from superconducting gravimeters already installed at Mount Etna. In particular, the significant  correlation with gravity data collected at sites 5 to 9 km away from PDN proves that effects due to bulk mass sources, likely related to volcanic processes, are predominant over possible local and/or instrumental artifacts.
This work demonstrates the feasibility to operate a free-falling quantum gravimeter in the field, both as a transportable turn-key device and as a drift-free monitoring device, able to provide high-quality continuous measurements under harsh environmental conditions. It paves the way to a wider use of absolute gravimetry for geophysical monitoring.

[1] www.newton-g.com

[2] D. Carbone et al., “The NEWTON-g Gravity Imager: Toward New Paradigms for Terrain Gravimetry”, Front. Earth Sci. 8:573396 (2020)

[3] V. Ménoret et al., "Gravity measurements below 10−9 g with a transportable absolute quantum gravimeter", Nature Scientific Reports, vol. 8, 12300 (2018)
Epistemic and aleatoric uncertainty maps in high resolution biophysical parameter retrieval 
Authors: Martínez-Ferrer Laura , Moreno-Martínez Álvaro , Muñoz-Marí Jordi , Izquierdo-Verdiguier Emma , Campos-Taberner Manuel , García-Haro Javier , Maneta Marco , Robinson Nathaniel , Clinton Nicholas , Kimball John , Running Steven W. , Camps-Valls Gustau
Published: March 2021

Biophysical parameters such as the Leaf Area Index (LAI), Fraction Absorbed Photosynthetically Active Radiation (FAPAR) and Canopy Water Content (CWC) are key inputs for ecological, meteorological and agricultural applications and models. Moreover, LAI and FAPAR are considered Essential Climate Variables (ECVs) which are feasible for global climate observation. Within this context, there are two main issues to achieve a reliable biophysical variable retrieval: cloud contamination and oversimplified uncertainties from the operational products. We propose a methodology based on a hybrid method which inverts a radiative transfer model (PROSAIL) with artificial neural networks (ANN) to produce 30m resolution continuous time series of biophysical variables (FAPAR, LAI, FVC, CWC, CCC) over large areas. To obtain gap free input reflectance data, we used a cloud optimized fusion algorithm (HISTARFM) combining MODIS and Landsat information. In addition, HISTARFM provides realistic uncertainty estimates along with the fused reflectances. This valuable information allows us to carry out an exhaustive uncertainty analysis considering the aleatoric uncertainty (data error) that needs to be propagated through the ANN, and the epistemic uncertainty (model error). We validate our biophysical retrieval with operational MODIS and Copernicus products. This study is performed over the contiguous US (CONUS) area with Google Earth Engine (GEE). The proposed retrieval methodology combined with the unprecedented GEE computational power allows to obtain high spatial resolution biophysical products and realistic uncertainty estimates to capture the needed spatial detail and adequately monitor croplands and heterogeneous vegetated landscapes at very broad scales.
Identification of Ice-Nucleating Macromolecules from Pollen Washing Water
Authors: Bieber Paul , Seifried Teresa M. , Grothe Hinrich
Published: March 2021

Pummer et al., 2012 found evidence that ice-nucleating particles from birch and conifer pollen are in the macromolecular size category, which has gained attention and verification by the scientific community of atmospheric ice nucleation. Moreover, the abundance of ice-nucleating macromolecules (INMs) is not limited to pollen, as Felgitsch et al., 2018 reported INMs to be extractable from branches, leaves and bark of birches. Furthermore, Seifried et al., 2020 demonstrated the atmospheric relevance of INMs, which are accumulated near the surface of trees, showing that INM are washed out by rain-droplets during rainfall events. However, the chemical composition of INMs still remains poorly understood.

To address atmospheric aerosol measurements to specific INMs, the biochemical identification of INMs is inevitable. To construct a concept, we analyzed birch pollen washing water (BPWW) regarding fluorescence and infrared (IR) spectroscopy. We found that the fluorescent bands of proteins are present in BPWW, however quenched by Quercetin-3O-sophoroside, a strong UV-light absorbing substance. Furthermore, BPWW shows intense IR bands in various regions of sugars. However, after a salting out, filtration and purification procedure, the IR spectra of ice nucleation active solutions show characteristic amide bands suggesting (glyco-)proteins to be one type of INMs from pollen.

 

References:

Pummer, B. G., Bauer, H., Bernardi, J., Bleicher, S., & Grothe, H. (2012). Suspendable macromolecules are responsible for ice nucleation activity of birch and conifer pollen. Atmospheric Chemistry and Physics, 12(5), 2541.

Felgitsch, L., Baloh, P., Burkart, J., Mayr, M., Momken, M. E., Seifried, T. M., ... & Grothe, H. (2018). Birch leaves and branches as a source of ice-nucleating macromolecules.

Seifried, T. M., Bieber, P., Felgitsch, L., Vlasich, J., Reyzek, F., Schmale III, D. G., & Grothe, H. (2020). Surfaces of silver birch (Betula pendula) are sources of biological ice nuclei: in vivo and in situ investigations. Biogeosciences, 17(22), 5655-5667.
The contribution of spatiotemporal modelling to spatial planning instruments on the local level
Authors: Lichtenwoehrer Peter , Neugebauer Georg , Abart-Heriszt Lore , Suppan Franz , Stoeglehner Gernot
Published: March 2021

In the course of the energy transition, spatial and temporal aspects of energy demand and renewable energy supply are increasingly coming to the forefront of scientific studies and political debates. In this context, the use of spatiotemporal models has been identified as a decisive methodology for integrated spatial and energy planning. However, the transformation of spatiotemporal results into concrete spatial planning instruments has not yet been sufficiently discussed. Therefore, this research aims to provide answers by using specific results of a case study in Austria. In the case study evaluation, energy demand is considered in high spatial resolution using statistic data in 250m raster cells as a basis. The results are supplemented with an assessment of high spatio-temporal solar energy potentials. Taking these results as a basis, the following questions are addressed: How can spatial and temporal evaluations of energy demand and supply support the energy transition by means of spatial planning on the local level? What measures with respect to renewable energy generation, storage and grid capacity can be derived and which effects are expected to be achieved? With respect to renewable energy provision, initial results reveal added value for the spatial delimitation of district heating supply areas. Further, building integrated solar energy generation reveals high shares of excess energy – both thermal and electric – which has to be properly used, taking into account different sectors of energy demand. As a consequence, the results of this research also offer the opportunity to reflect on the benefits of sector coupling, as well as the new organization of energy supply via energy communities.
A high-resolution multi-phase thermo-geophysical permafrost rock model to verify long-term ERT monitoring at the Zugspitze (German/Austrian Alps)
Authors: Schroeder Tanja , Krautblatter Michael
Published: March 2021

In the context of climate change, permafrost degradation is a key variable in understanding rock slope failures in high mountain areas. Permafrost degradation imposes a variety of environmental, economic and humanitarian impacts on infrastructure and people in high mountain areas. Therefore, new high-quality monitoring and modelling strategies are needed.

We developed a new, numerical, thermo-geophysical rock permafrost model (TGRPM) to assess spatial-temporal variations of the ground thermal regime in steep permafrost rock walls on the basis of 13-years of Electrical Resistivity Tomography (ERT) monitoring of permafrost at the Zugspitze. TGRPM is a simple to understand and workable numerical 2D MATLAB-model, which is adaptable to different topographic and sub-surface conditions, and further relies on a minimum of input-data to assess the surface energy balance and the ground thermal regime. It simulates the thermal response for permafrost rock walls, including their complex topography, to climate forcing over multiple years. It aims to assess seasonal and long-term permafrost development in steep alpine rock walls, as well as serving as a straightforward calculation routine, which is solely based on physical processes and does not require any fitting of certain parameters.

At first, the model was tested against direct temperature measurements from the LfU-borehole at the Zugspitze summit to prove its accuracy. Then, it is run against a 13-year ERT data-set from the Zugspitze Kammstollen to validate the ERT measurements.

Here, we show the first thermo-geophysical model referencing thermal evolution in a permafrost rock wall with temperature-calibrated ERT. The TGRPM successfully computes the thermal evolution within the Zugspitze mountain ridge from a 2D coupled energy balance and heat conduction scheme in complex topography. It furthermore validates the temperature-resistivity relationship by Krautblatter et al. (2010) for natural rock walls reaching a correlation of 85 to 95 % between measured, ERT-derived and modelled temperatures.

Krautblatter, M., Verleysdonk, S., Flores-Orozco, A. & Kemna, A. (2010): Temperature-calibrated imaging of seasonal changes in permafrost rock walls by quantitative electrical resistivity tomography (Zugspitze, German/Austrian Alps). J. Geophys. Res. 115: F02003.
A calibrated visual web camera network for measuring volcanic plume heights: technical aspects and implementation for operational use
Authors: Barnie Talfan , Hjörvar Tryggvi , Sigurðsson Eysteinn Már , Pfeffer Melissa Anne , Arason Þórður , Barsotti Sara
Published: March 2021

The Icelandic Meteorological Office (IMO) maintains a network of web cameras for monitoring the environment and identifying possible hazards, including reduced atmospheric visibility, changing river flow conditions and snow accumulation. Recently, the network has been expanded to improve the volcano monitoring capacity, with the specific aim of observing eruption onset and estimating volcanic plume heights. Here, we present how sites for cameras are chosen, the environmental constraints that inform the two camera designs currently in use, how the data is transmitted to the institute, stored, and pushed through the data processing system, and the different techniques used to calibrate the cameras and calculate the orientations of plumes such that measurements can be made from the images they produce. Camera calibration is a particular challenge for such a diverse range of cameras and environments, with some cameras already installed and inaccessible, and here we show how we use laboratory calibration, feature matching, horizon matching and star matching to find the internal camera geometry and camera orientation in different scenarios. Once calibrated, geometric measurements can be extracted from the images by either providing constraints from Numerical Weather Prediction (NWP) models on the likely orientation of the plume, or by using two images with different views, which provide enough information to pin down a point in three dimensions. In the latter case we show how ray projection can be used to locate a point. These plume calculation tools and final images are made available to the forecasters and natural hazard specialists on-duty using an interactive webpage. The plume height time series are easily saved for ingestion into the Volcanic Eruptive Source Parameter Assessment (VESPA) inversion system designed to assess eruption intensity and to provide calculated eruption source parameters in input to the tephra dispersion forecasting model.
Assessing of tight reservoir by combining the porosity of geological units, and simulated images of rock types: A case study
Authors: Boussa Lamia , Boudella Amar , Almeida José
Published: March 2021

Reservoir characterization and flow studies require accurate inputs of petrophysical properties such as porosity, permeability, water and residual oil saturation and capillary pressure functions. All these parameters are necessary to evaluate, predict and optimize the production of a reservoir.

This study is the continuity of a previous work that summarize the construction of a net rock aerial map by combining stochastic simulation of rock types and processed seismic data. In this case study; petrophysical data are integrated to construct a 3D model of porosity corresponding to the 3D model of rock type. This is in order to further understand the intricacies of the geostatistical methods used and the impact of the technique on the resulting uncertainty profile

For the construction of 3D model of porosity corresponding to the 3D model of rock types, a geostatistical workflow encompassing the modelling of experimental variograms and sequential Gaussian simulation (SGS) were used. The geostatsitical methodologies of stochastic simulation such as SGS enabled the generation of several realistic scenarios of constinuous data, such as porosity, within a volume, thus facilitating the association of local probabilities of occurrence of each rock type.

The resulting porosity image properly combines the available seismic and well data and balance the local and regional uncertainty of the studied reservoir volume.

Keywords: Geostatistics, Sequential Gaussian Simulation (SGS), Rock types, Porosity, Uncertainty, Spatial resolution.
Pan-Arctic and regional trends of reflectance, clouds and fluxes: implications for Arctic Amplification
Authors: Lelli Luca , Khosravi Narges , Vountas Marco , Burrows John
Published: March 2021

It is now well known that the sea ice extent in the Artic has been shrinking in the past three decades in the period known as the Arctic Amplification. A simple assumption would be that if the sea ice extent has been reduced, then the spectral reflectance at the top of the atmosphere - RTOA - would have also decreased across the Arctic. On the other hand, Arctic reflectivity also largely depends on the presence of clouds, shielding the underlying surface, and on changes of their optical and physical properties. Thus, the assessment of trends of spectral reflectivity and cloud properties are essential to understand those forcings and feedbacks considered drivers of Arctic Amplification as well as the interactions between the components of the Arctic cryosphere. In the reported study we observationally tackle the stated problem investigating changes of RTOA at selected wavelengths making use of spaceborne measurements of the Global Ozone Monitoring Experiment (GOME onboard ERS-2 and MetOp A/B/C) and of the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY onboard Envisat) for the period 1995-2018. We complement this record with cloud properties and fluxes at top of the atmosphere and at the surface, inferred from measurements of the post-meridiem orbits of the Advanced Very High Resolution Radiometer (AVHRR onboard POES). Although the Pan-Arctic reflectivity has decreased, the analysis of regional trends shows distinct areas where the reflectivity trends diverge. While darkening areas can be attributed to seasonal sea ice decline, an increase of Arctic brightness over sea ice free regions can be largely attributed to changes in the optical properties of clouds. While the multiyear mean of the radiative forcing by clouds points to a TOA cooling and a surface warming, its trends exhibit opposite tendencies. In the last two decades, the cloud radiative effect at TOA is expected to warm the lower latitudes (below 75 N) and to cool the circumpolar belt, while an opposite trend at BOA, amounting to 5 W m-2 per decade, cools the lower Arctic latitudes and warms the permanent sea ice region, this effect being more pronounced in spring months (April to June) than in summer months (July to September).
Role of kinematic thermomechanical modelling on constraining asymmetric continental break up
Authors: Perron Paul , Le Pourhiet Laetitia , Jourdon Anthony , Cornu Tristan , Gout Claude
Published: March 2021

For a long time, the complexity of the lithosphere was ignored by numerical modelling because the inherited structural and compositional complexity of the “real” lithosphere is indeed mainly unknown to geologists so modeler preferred to understand first order parameters such as rate of extension, lithospheric thickness, mechanical coupling or decoupling at the Moho. These models were not representative of any particular region but they were helpful. As a wider community of geologist became interested in numerical modelling, a growing number of numerical models have attempted to account for a major player in structural geology: inheritance. However, the complexity of “real” Earth has been simplified and “idealized” where inherited “anomalies” (e.g. fault, pluton, craton) or a combination of them has been added without really knowing the exact initial conditions which are the unknown of the problem. Yet another approach has been to add a lot of them in a more or less random mater or to replace them by initial noise in the parameters. None of these approaches actually fulfil the need for end-users community to have predictive models.

Realizing that structural inheritance is some kind of kinematic forcing in the solution of the models but also that it is not possible to anticipate and identify all the geological structures that can be inherited in rifted margin lithospheres, we have developed a new approach, through the integration of a new kinematic module to pTatin2D thermomechanical code, permitting to understand the kinematics of deformation of the continental lithosphere and asthenosphere through time leading to the establishment of rifted margins. The method is settled and validated by fitting the architecture (i.e. basement, Moho, LAB, Tmax) and by solving the kinematics of a random unknow 2D cross section extracted from 3D thermomechanical rifted margin model.

This new tool aims to help geologists to better constrain and draw on their 2D geological cross sections the position of the Moho, the Lithosphere-Asthenosphere boundary (LAB), the temperature isotherms and the heat flux.

Key words: Kinematic thermomechanical modelling, asymmetric rifted margin architecture, modelling method.
Creating community and empowering underrepresented geospatial professionals at Women in Geospatial+
Authors: Szeto Sabrina H. , Wagemann Julia , Porter Heather , Omoja Sharon , Vrinceanu Cristina
Published: March 2021

Women in Geospatial+ is a professional network to promote gender-equality and diversity in the geospatial industry and academia. We are a vibrant and active community with more than 2,200 registered members from all over the world and over 14,000 followers on Twitter & LinkedIn. We have a range of activities all with the aim to inspire, unite and empower us as individuals but also us as a community.

This community brings together women and other people from underrepresented gender backgrounds in the geospatial field by providing a safe platform on Slack for open communication and exchange, which is especially crucial for networking during the COVID-19 era. We promote and foster the professional development of our members by sharing geospatial news and job vacancies as well as articles about diversity and tips about leadership and career development. We regularly run online career development workshops and panel discussions. Each week, we post a profile on LinkedIn to feature the work and achievements of women geospatial leaders. In 2020, our second international mentorship programme cohort grew to over 110 participants. We also launched a global speakers database which allows event organisers to search for and invite speakers from underrepresented gender backgrounds. 

This presentation will highlight key activities of the Women in Geospatial+ network, tapping into some current facts and figures on diversity in the geospatial field. We will explain how to join the community and how you can contribute to its success and expansion. Let us change the status quo together by creating a strong network of Women in Geospatial+ leaders and changemakers.
Investigation of stable vertical density structures formed in water bodies in zones of active technogenesis on an example of the Solikamsk-Bereznikovsky industrial hub (RF)
Authors: Parshakova Yanina , Lyubimova Tatyana , Anatoliy Lepikhin
Published: March 2021

Due to the active development of the Verkhnekamskoye deposit of potassium and magnesium salts (Russia) not only watercourses - wastewater receivers, but also water bodies that are not directly affected by technogenic impact fall into the zone of its influence. This impact, due to the high density of brines, is very important from an environmental point of view, but it is not recorded within the framework of traditional production monitoring. The carried out field observations show that the content of macrocomponents in water is significantly heterogeneous in depth and is characterized by the presence of a sharp jump of density. The concentration of salts in the near-bottom horizon is more than an order of magnitude higher than their content in the near-surface layer.

The situation is significantly complicated by the fact that during spring floods and during the passage of rain floods, less mineralized, fresh waters "slide" without mixing with more "dense" water masses located below the density jump layer. Therefore, the efficiency of washing of these reservoirs is significantly reduced. Since water intake for production purposes, as a rule, is made from the bottom horizons, this stratification creates serious problems with ensuring sustainable water supply to production facilities.

To solve these applied problems, the study of the formation of stable density structures was carried out on the basis of combined field studies and computational experiments performed on the basis of a hydrodynamic model in a full 3D formulation in a non-hydrostatic approach. The studies carried out made it possible to evaluate and compare various technologies for increasing the sustainability of technical water supply from these water bodies, to choose the most efficient of them.

The study was supported by Russian Science Foundation (grant 17-77-20093).
Modelling wildfire ash transport by concentrated flow
Authors: Neris Jonay , Brown Robert E. , Robichaud Peter R. , Elliot William J. , Santin Cristina , Doerr Stefan H.
Published: March 2021

Wildfire ash is a mixture of pyrogenic organic and inorganic materials with high concentration in nutrients and potential contaminants that is easily mobilized by runoff. Ash has been identified as a major threat to water quality since it can impact aquatic life and disrupt water treatment operations when is washed off into water bodies. The ability to modelling ash transport, however, is in its infancy.  One reason for this is that the relationship between runoff and ash transport for concentrated flow has not been described yet, limiting the capabilities of current runoff-erosion models to predict ash transport and delivery in fire-affected areas.

To fill this knowledge gap, we conducted a series of laboratory experiments on ash transport using concentrated flow on flumes. Ash collected from US conifer forest burned at high severity was applied at two different rates (corresponding to layers of 1 and 3 cm thickness) to an artificial substrate of gravel and sand attached to the bottom of the flumes that simulates soil roughness. Three different flow rates were consecutively applied to each flume in all possible combinations (6 flow rate combinations and 6 replicates per combination and ash thickness).

The results show that ash is easily transported by concentrated flow, confirming previous observations on ash mobility. The runoff rate required to start transporting the ash was close to 0 (0.005 L min-1 for both 1 and 3 cm ash layers) and the average concentration of ash in the runoff once this process started was considerably high (120 and 176 g L-1 for 1 and 3 cm ash layers respectively), probably due to the low density and cohesion of this fire by-product. The results also show that ash depletion is a critical process when modelling ash transport and, thus, that ash transport by concentrated flow is better modelled using a variable sediment transport rate to account for ash decay with consecutive rainfall events. This is especially true for the 1 cm ash layer. The relationships between runoff and ash transport for concentrated flow obtained here for the evaluated ash type and loads are critical parameters to predict ash transport and will be used to refine ash transport capabilities of WEPPcloud-WATAR, a new tool aimed at predicting ash contamination risks after wildfires.