bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation of 3D building model using different LoD
Authors: Dziok Wojciech , Jasińska Aleksandra , Puniach Edyta , Ćwiąkała Paweł
Published: March 2020

            With the technological progress, the demand for a three-dimensional presentation of the world around us is growing. Currently, modelling of urban space in 3d based on presenting it as simple geometric solids is not able to satisfy the needs of the constantly growing market. There are also noticeable trends aimed at representing the real world as faithfully as possible in virtual space.

            The purpose of this work is to show the differences between the individual levels of detail (LoD) of the building facade model obtained using classic geodetic measurements as well as ground photogrammetry and UAV photogrammetry. For this purpose, pictures of the building facade were taken and its characteristic elements were measured so that the generated model was metric.

            Creating a vector model of the facade consisted in modelling individual blocks based on points obtained from the total station measurement. The model was generalized for individual levels of detail using fewer points to make it. Subsequently, vector models were textured by photos.

In addition, oblique facade photos were developed, and then a triangular mesh model was made from the dense point cloud generated on their basis. The model was analyzed for meeting the accuracy criteria of individual LoDs in order to determine whether the use of only photogrammetric data allows the generation of a suitably detailed spatial model.

The resulting models were compared with each other, thanks to which it is possible to verify whether the facade is symmetrical and how repeatable its architectural elements are. The outcome also enables the assessment of the accuracy with which the building elements should be measured in order to obtain a reliable model that meets the criteria of the assumed LoD level for the resulting product.
InSAR as a tool to monitor nuclear decommissioning – a case study across the Fukushima Daiichi Nuclear Power Plant, Japan
Authors: Bestard Jack , Magnall Nathan , Holley Rachel , Thomas Adam
Published: March 2020

The Fukushima Daiichi Nuclear Power Plant, Japan, underwent a series of sequential meltdowns in 2011 related to the magnitude 9.0 earthquake and tsunami of the same year - causing the world’s second ‘Level 7’ nuclear event after Chernobyl. Japan and the Tokyo Electrical Power Company (TEPCO) have been proactive in taking steps towards decommissioning the now hazardous site, with a clean-up timeline continuing work for another 30-40 years. However, this creates a need for long-term monitoring strategies that mitigate radiation hazards for the personnel involved with the decommissioning. Remote sensing can fill this emerging need, more specifically with Interferometric Synthetic Aperture Radar (InSAR).

InSAR can monitor ground and structure stability with millimetre scale accuracy, as well as create a historical baseline for past movement using data from ESA’s Sentinel-1 satellite mission. Here we show the applicability of InSAR monitoring across the Fukushima plant using Sentinel-1 data spanning October 2015 to October 2019. Our results clearly show an uplift signal of ~75 mm around the reactor, during the time period directly coinciding with the implementation of a perimeter ice wall which was constructed to mitigate groundwater leeching.

This study demonstrates the benefits of InSAR to monitor ground stability in near-real time, and across a wide area, without the need for direct interaction with such a hazardous site. Via this study, we have demonstrated that InSAR is a powerful technique for monitoring potential ground stability issues at highly hazardous sites, with applications for the engineering, oil and gas, and mining sectors.
Study of pre-treatments of fly ashes aimed to the reuse as construction materials: chemical and mineralogical characterization
Authors: Destefanis Enrico , Caviglia Caterina , Bernasconi Davide , Bonadiman Costanza , Confalonieri Giorgia , Pastero Linda , Tassinari Renzo , Pavese Alessandro
Published: March 2020

The management of waste and its sustainable reuse is one of the most important concern in our society in recent years, together with the increasing need to find primary materials without resorting to new extraction of resources. In this context, the thermovalorization of municipal solid waste (MSW) is currently the method that is spreading and replacing landfill disposal; the thermal treatment allows to reduce the volumes significantly, producing energy and returning bottom ashes (BA) and fly ashes (FA) in the measure of 20% and 5% of the total waste respectively.
The MSW incineration BA are classified as non-hazardous waste and can be reused as a raw material after some physical-chemical treatments.
The FA, on the contrary, are classified as hazardous waste and according to current legislation, they are usually subjected to vitrification treatments and stored in dedicated landfills. The hazard is due to the high content of soluble salts (chlorides and sulfates) and heavy metals (mainly Zn and Pb). Therefore, for their possible reuse as construction materials (e.g. ceramic, cement, concrete aggregates) or base roads, a preliminary stabilization step is required which often requires the use of significant quantities of energy.
In the present work, low energy cost methods are considered to reduce the dangerousness of FA and consequently make them more easily treatable for their reintegration into the production cycles.
Among the methods, washing of FA with water is examined, to find the lowest L / S ratio in the reduction of salts and heavy metals, analyzing the dissolution kinetics and the mineralogical content of fly ash before and after each washing treatment.
For a better definition of the kinetics, the FA are previously submitted to particle size separation to understand in which fractions the most dangerous substances are concentrated.
Washing treatments can be useful to remove or reduce soluble salts, in particular chlorides, by using a different liquid / solid (L / S) ratio, in order to obtain a more suitable material for the solidification / stabilization treatments carried out by geopolymerization or in cement.
The eluates of washing are also taken into consideration to evaluate the recovery of elemental species of interest and the purification of the liquid phase with biochar.
Augmented reality for volcanic and seismic risk communication
Authors: Reitano Danilo , Falsaperla Susanna
Published: March 2020

Dealing with topics concerning natural risk management in a volcanic environment, can greatly benefit from innovative techniques. In particular, Augmented Reality (AR) and Virtual Reality (VR) are well known by Native Digital and can be used by lower-level and university students to promote their understanding of natural risks.

3DTeLC is a three-year trans-European project funded by the Erasmus+ Key Action 2 programme: “Cooperation for Innovation and Exchange of Good Practices, a European scheme that fosters higher education partnerships” (https://www.erasmusplus.org.uk/key-action-2).

The main goal of this project is to help young students to become highly-skilled professionals in the field of environment and geosciences, gaining knowledge in image and 3D-spatial analysis, data management and informatics, and strengthening their mathematical and numerical skills in Earth observation and data analysis.

In the framework of this project INGV team has developed a “Talking poster”, using a custom AR tool to propose a user friendly approach aimed at the reduction of volcanic and seismic risks.
Dependence of benefits of convection permitting models on large-scale conditions
Authors: Belusic Danijel , Lind Petter , Landgren Oskar , Matte Dominic , Pedersen Rasmus Anker , Toivonen Erika , Hansen Felicitas , Wang Fuxing
Published: March 2020

Current literature strongly indicates large benefits of convection permitting models for subdaily summer precipitation extremes. There has been less insight about other variables, seasons and weather conditions. We examine new climate simulations over the Nordic region, performed with the HCLIM38 regional climate model at both convection permitting and coarser scales, searching for benefits of using convection permitting resolutions. The Nordic climate is influenced by the North Atlantic storm track and characterised by large seasonal contrasts in temperature and precipitation. It is also in rapid change, most notably in the winter season when feedback processes involving retreating snow and ice lead to larger warming than in many other regions. This makes the area an ideal testbed for regional climate models. We explore the effects of higher resolution and better reproduction of convection on various aspects of the climate, such as snow in the mountains, coastal and other thermal circulations, convective storms and precipitation with a special focus on extreme events. We investigate how the benefits of convection permitting models change with different variables and seasons, and also their sensitivity to different circulation regimes.
Multi-method efficiency analysis of Rainwater Harvesting Systems in Corredor Seco region, Central America
Authors: Bresci Elena , Castelli Giulio , Ursino Nadia , Giacomin Antonio , Preti Federico
Published: March 2020

The region of Corridor Seco (Dry Corridor, including parts of Guatemala, Honduras and El Salvador) has been facing multiple food crises caused by extreme weather events, water scarcity and land degradation phenomena. In this situation, Rooftop Water Harvesting (RWH) systems can effectively enhance local livelihoods, especially in marginalized communities, by providing an additional water source for domestic use, livestock, and irrigation of small horticultural plots which are key for vegetable production and thus for vitaminic input in a well-balanced diet.

Dimensioning sufficient storage tanks for rainwater collection is key, since smallholder farmers’ capabilities are often hindered by low financial capacity as well as by limited land extension for reservoir building.

Efficiency of storage tanks and design criteria for water harvesting systems are investigated on the base of rainfall time series analysis, probabilistic risk assessment and Monte Carlo simulation (Ursino, 2016). The approach is tested on a series of (RWH) systems built in Guatemalan part of the Corredor Seco, Chiquimula department, with sustainable and appropriate building techniques, but with variable size due to the variability of each household. Factors affecting efficiency of storage tanks are discussed to inform future sustainable water management planning in the area.

Reference:

Ursino, N. Risk Analysis Approach to Rainwater Harvesting Systems. Water 2016, 8, 337. https://doi.org/10.3390/w8080337
Photocatalytic properties of Cu2(Fe,Mn)SnS4 microspheres synthesized via hydrothermal method
Authors: Waluś Edyta , Manecki Maciej
Published: March 2020

The most industrial activities, that require organic dye materials for their applications, release a remarkable fraction of effluent water. As a result, serious environmental problems emerge due to the toxicity of many compounds which these industrial processes produce. The development of inexpensive and green methods for degradation of such organic dye laden water constitutes a landmark for the mitigation or even the elimination of the industrial sewage. Among many strategies, photocatalysis is regarded as the most viable one due to its usage of sunlight to decomposing organic pollutants.

The unlimited applications of nanocrystalline semiconductor materials in all sorts of technological fields, whether photochemical, biological, photovoltaic or photocatalysis have pushed to develop a new assortment of materials featuring novel properties for advanced applications. Semiconductor properties of stannite Cu2FeSnS4 make it a potential candidate for application in photocatalytic industry. In nature, it is a common sulfide mineral which is formed as a result of hydrothermal processes. Its crystal structure allows for numerous substitutions including replacement of Fe by Mn.

In this report, the photocatalytic activity of  Cu2FeSnS4 (CFTS) and Cu2MnSnS4 (CMTS) synthetic microspheres for degradation of environment polluting dye such as methylene blue (MB) has been explored under UV light illumination. The unique morphology of the as-synthesized nanomaterial is expected to play a major role in tailoring the optical and electrical properties for the possible photo-voltaic application. The photocatalytic activity shows the potential use of this material as an efficient photocatalyst for wastewater treatment.

Modified stannite was synthesized by hydrothermal method using reactions of metal salts and sulfur in hot ethylene glycol at presence PVP solution in an autoclave at 195oC. The crystallinity, structural features, morphology and chemical composition were investigated using XRD, Raman, FTIR, and SEM - EDS. Synthetic Cu2(Fe,Mn)SnS4 solid solutions are composed of spheres 1 – 1.5 µm in size, with rough surface and concentric internal structure. The structure matches hexagonal stannite. The promising optoelectrical and photocatalytic properties of CFTS and CMTS microspheres make them a potential candidate for photovoltaics as well as for effective wastewater treatment, providing further study has to be carried out to improve specific properties.

Financial support for the research was provided by Polish Ministry of Higher Education grant No. DI2016 004946 under "Diamond Grant" program.
Understanding risk and resilience in alpine communities: A conceptual model for coupling human and landscape systems
Authors: Keiler Margreth , Ramirez Jorge Alberto , Hossain Md Sarwar , Haisch Tina , Martius Olivia , Ifejika Speranza Chinwe , Mayer Heike
Published: March 2020

Disasters induced by natural hazards or extreme events consist of interacting human and natural components. While progress has been made to mitigate and adapt to natural hazards, much of the existing research lacks interdisciplinary approaches that equally consider both natural and social processes. More importantly, this lack of integration between approaches remains a major challenge in developing disaster risk management plans for communities. In this study, we made a first attempt to develop a conceptual model of a coupled human-landscape system in Swiss Alpine communities. The conceptual model contains a system dynamics (e.g. interaction, feedbacks) component to reproduce community level, socio-economic developments and shocks that include economic crises leading to unemployment, depopulation and diminished community revenue. Additionally, the conceptual model contains climate, hydrology, and geomorphic components that are sources of natural hazards such as floods and debris flows. Feedbacks between the socio-economic and biophysical systems permit adaptation to flood and debris flow risks by implementing spatially explicit mitigation options including flood defences and land cover changes. Here we justify the components, scales, and feedbacks present in the conceptual model and provide guidance on how to operationalize the conceptual model to assess risk and community resilience of Swiss Alpine communities.
How can natural hazard scientists enhance their contribution to building sustainable and resilient societies?
Authors: Gill Joel C. , Taylor Faith E. , Duncan Melanie , Mohadjer Solmaz , Budimir Mirianna , Mdala Hassan
Published: March 2020

Reducing disaster risk is critical to securing the ambitions of the Sustainable Development Goals (SDGs), and natural hazard scientists can help to do this. Their understanding of Earth dynamics underpins hazard analysis, which (alongside analysis of other disaster risk drivers) in turn informs the actions needed to manage and reduce disaster risk. Here we outline how natural hazard research scientists can contribute to the planning and development of sustainable and resilient communities through improved engagement in disaster risk reduction (DRR). Building on existing good practice, this talk therefore aims to provoke discussion in the natural hazard science community about how we strengthen our engagement in DRR. We first set out seven reflections on improving the integration of natural hazard science into DRR: (i) characterise multi-hazard environments, (ii) prioritise effective, long-term partnerships, (iii) understand and listen to stakeholder, (iv) embed cultural understanding into natural hazards research, (v) ensure improved and equitable access to hazards information, (vi) champion people-centred DRR (leave no one behind), and (vii) improve links between DRR and sustainable development. We then proceed to synthesise key actions that natural hazards scientists and research funders can take to improve education, training, and research design, and to strengthen institutional, financial and policy actions. We suggest that these actions support the translation, adoption and effective application of natural hazards science, and will enable the natural hazard science community to contribute more effectively to the integrated work needed to improve DRR activities.
Investigating the Relation of Arctic Tropospheric Bro Derived by Satellite Remote Sensing to Sea Ice Age and Meteorological Driving Mechanisms Under the Impact of Arctic Amplification
Authors: Bougoudis Ilias , Blechschmidt Anne-Marlene , Richter Andreas , Seo Sora , Burrows John
Published: March 2020

Arctic Amplification, the rapid increase of air temperature in higher latitudes over the last decades, is expected to have drastic impacts on all the sub-systems of the Arctic ecosystem. Bromine Oxides play a key role in the atmospheric composition of the Arctic. During polar spring, bromine molecules are released from young sea ice covered regions.  A rapid chemical chain reaction starts, the -so called 'bromine explosion', which depletes ozone, alters the production of OH, and thereby eventually changes the oxidizing capacity of the troposphere. Halogens oxidize elemental to gaseous mercury, which may then be deposited and harm the ecosystem. Based on current literature, there is considerable uncertainty on the impact of Arctic Amplification on halogen evolution. On one hand, the melting of multi-year sea ice should result in formation of more young sea ice, which favors bromine release. On the other hand, BrO explosion events are triggered by low temperatures, an effect expected to be reduced due to Arctic Amplification. Moreover, changes of other meteorological drivers, such as cyclone frequency and wind speed may impact on BrO amounts in the Arctic troposphere.

In this study, a long-term time-series of tropospheric BrO derived from 4 UV-VIS instruments (GOME, SCIAMACHY, GOME-2A, GOME-2B) is used as a basis, in order to investigate the impact of Arctic Amplification on BrO amounts in the Arctic. The long-term BrO data is being compared to sea ice age (NSIDC) and meteorological (air temperature, mean sea level pressure, wind speed and boundary layer height from ERA-5 & ASR-2) data. Our results focus on determining the relation between tropospheric BrO and its drivers, and especially on how the drivers impact on the formation of BrO plumes. Different cases studies throughout the 22 years of the BrO dataset were performed and evaluated. The changes in the tropospheric BrO abundances come in general agreement with changes in the drivers of BrO explosion events.

 

We gratefully acknowledge the funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Projektnummer 268020496 – TRR 172, within the Transregional Collaborative Research Center “ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)³”.
Multi-scale numerical modelling of debris flow: coupling 2D and 3D simulation strategies
Authors: Pasqua Andrea , Leonardi Alessandro , Pirulli Marina
Published: March 2020

Debris flows consist of mixtures of poorly sized sediments mixed with mater, moving with high speed within natural channels. They pose a constant threat to settlements located on mountainous terrains, with casualties and economic losses reported every year. An efficient numerical model, able to aid in the design of mitigation structures, is a long-sought tool by the community of practitioners.

One of the challenging aspects of debris flows is their complex multiscale nature. Typically, events are characterized by long runouts, with debris transported for kilometres after their initial mobilization. At the same time, the scale of interaction between flow and obstacles is much smaller, because debris-resisting structures are seldom taller than a few meters. For this reason, numerical methods typically focus on one of two aspects: the runout simulation, or the flow-structure interaction problem. This is however problematic: the type of interaction is a function of the equilibrium conditions achieved by the flow during runout, which can hardly be reconstructed if the phenomenon is not reproduced in its entirety.

In an effort to bypass this problem, we present here a coupling strategy between RASH3D, a depth-averaged model based on the shallow-water equation, and the Lattice-Boltzmann Model (LBM), an innovative 3D Navier-Stokes solver. RASH3D is employed for simulating the initial mobilization and flow runout. Before impact with a barrier, the flow variables are converted from their depth-averaged values into full 3D fields, inverting the depth-averaging procedure. The 3D flow-structure interaction is then solved with LBM. The most important and innovating point about this strategy consists in saving computational time using RASH3D without losing any important information (velocity, pressure, volume etc…) at interaction between structures and flow thanks to LBM, thus reconstructing with good precision and efficiency the whole problem.

References:

Leonardi, A., Wittel, F. K., Mendoza, M., Vetter, R., & Herrmann, H. J. (2016). Particle-Fluid-Structure Interaction for Debris Flow Impact on Flexible Barriers. Computer-Aided Civil and Infrastructure Engineering, 31(5).

Thorimbert, Y., Lätt, J., & Chopard, B. (2019). Coupling of lattice Boltzmann shallow water model with lattice Boltzmann free-surface model. Journal of Computational Science, 33, 1-10.
Eocene post-collisional magmatism in Himalaya orogenic belt: evidence from petrography, zircon U-Pb age and Sr-Nd-Hf isotope of the Mayum alkaline complex, southern Lhasa subterrane
Authors: Chen Xiaoshuang , Xu Haijin
Published: March 2020

Alkaline magmatism is commonly generated in extensional settings, playing an important role in constraining the timing of slab breakoff. Eocene post-collisional magmatism is widely distributed along the Gangdese belt of southern Tibet. However, few Eocene post-collisional alkaline magmatism has been identified. Here, we present a comprehensive study of whole-rock geochemistry, zircon U-Pb ages and Sr-Nd-Hf isotopes of the Mayum alkaline complex from the Southern Lhasa Subterrane, providing an insight into the timing of breakoff of the Neo-Tethyan slab. The alkaline complex is composed of amphibolite syenite, quartz syenite and alkaline granite. The mafic microgranular enclaves are ubiquitous in the syenites. Zircon U-Pb analyses indicates that the alkaline rocks were generated in Early Eocene (ca. 53-50 Ma). These ages suggest that the alkaline rocks emplaced shortly (10-15Ma) after the continental collision between the Indian and Eurasian plates. The alkaline rocks have high SiO2 (64.32-77.36 wt.%), Na2O + K2O (6.63-9.03 wt.%) contents, low MgO (0.14-2.52 wt.%) contents. These rocks show obvious arc-like geochemical features in trace elements, i.e., enrichment in LILEs (e.g., Rb, K), LREEs, Th and U, and depletion in HFSEs (e.g., Nb, Ta, Ti), HREEs with strongly to moderately negative Eu anomalies (δEu=0.28–0.72). These features together with high FeOT/MgO, Ga/Al, Ce/Nb and Y/Nb values, and low Ba, Sr contents, suggesting that the Mayum alkaline rocks belong to an A2-type granitoids. Besides, the alkaline rocks have homogeneous initial 87Sr/86Sr ratios (0.7052-0.7059) and negative εNd(t) values (-2.1 to -0.9) for whole-rock, and positive zircon εHf(t) values (+0.73 to +11.16). Nd-Hf isotope decoupling suggests that the alkaline was likely produced by mixing of mantle- and crust-derived magmas under a post-collisional extensional setting. Combined with previous published results, we propose that the slab breakoff of the subducting Neo-Tethyan oceanic lithosphere at least prior to Early Eocene (ca. 53Ma). The Eocene Mayum alkaline complex might be related to asthenosphere upwelling trigged by the slab breakoff.
Oriented particles in microwave and submillimeter radiative transfer simulations of ice clouds
Authors: Brath Manfred , Ekelund Robin , Eriksson Patrick , Lemke Oliver , Buehler Stefan A.
Published: March 2020

Observations of Global Precipitation Measurement Microwave Imager (GMI) at 166 GHz consistently show polarized scattering signals of ice clouds. Conceptual models indicate that these signals emerge from oriented ice particles. Existing databases of scattering data of realistically shaped ice crystals for microwave and submillimeter typically assume total random orientation of ice particles. This is often a very reasonable assumption, but cannot explain the polarized ice cloud signals. Only few works considering oriented ice crystals exist, but they only consider microwave. With the upcoming Ice Cloud Imager (ICI) on board of Metop-SG B satellite, there will be additional dual-polarization measurements at 243 GHz and 664 GHz. These measurements will deliver new insights about clouds and their structure, if we know the scattering properties of oriented and realistically shaped ice crystals.

We provide publicly available scattering data for 51 different sized hexagonal plates and 18 different sized plate aggregates for 35 frequencies between 1 GHz and 864 GHz. The ice particles are assumed to be azimuthally randomly oriented with a fixed but arbitrary tilt angle. The scattering data for azimuthal random orientation is much more complex than for total random orientation. The scattering data of azimuthally randomly oriented particles depends in general on the incidence angle and two scattering angles compared to only one scattering angle for total random orientation. The scattering data is based on discrete dipole approximation simulations in combination with a self-developed orientation averaging approach.

We present detailed radiative transfer simulations of polarized GMI observations at 166 GHz and ICI observations at 243 GHz and at 664 GHz using our scattering data. The simulations of GMI recreate the observed polarization patterns. Analysis shows that not only orientation affects the polarization signal but also the hydrometeor composition. Furthermore, particle orientation also affects single polarized observations. Ignoring orientation can cause a negative bias for vertically polarized observations and a positive bias for horizontally polarized observations.
Predictability of precipitation extremes over the Mediterranean
Authors: Giuntoli Ignazio , Fabiano Federico , Corti Susanna
Published: March 2020

Intense precipitations events are associated with impacts like damages to infrastructures, economic activities, agricultural crops, power production and society in general. The ability to predict extreme precipitation events months in advance is therefore of great value in densely populated areas like the Mediterranean and may be achieved using seasonal prediction systems like the Copernicus Climate Change Services (C3S) suite of models. Using weather regimes (WRs) from 500 hPa geopotential heights over the Mediterranean the two main objectives of this study are: first to identify how these regimes are linked to extreme precipitation events over the region using reanalysis data; and second to assess the ability of the C3S models in reproducing/predicting these extreme events. We identify four weather regimes for the winter season (DJF) describing the atmospheric circulation in the Mediterranean using the 1993-2016 period as reference, i.e. maximum availability of C3S hindcasts. We thus provide an assessment of the models’s ability in predicting extreme precipitation over the Mediterranean having quantified how daily precipitation anomalies are associated to each WR.
Colloidal Aspects of the Formation of the Interactions between Humic Substances and Surfactants
Authors: Kalina Michal , Duchacek Tomas , Krouska Jitka , Sedlacek Petr , Smilek Jiri
Published: March 2020

Humic substances (HS) represent fascinating heterogeneous mixture of natural molecules, which possess a high potential to interact with various substances e.g. metals, surfactants, dyes, pesticides. This beneficial property allows their further utilization as the reactive part of sorbents with possible applications in remediation processes of soils and waste waters treatment plants. Surfactants represent a group of substances, which are artificially introduced in the nature by human driven applications causing the undesirable foaming of waters and enhancing the solubility of hydrophobic organic pollutants such as highly toxic polycyclic aromatic hydrocarbons. The present work is focused on the study of colloidal aspects of interactions between selected representatives of surfactants and humic substances, as the example of a promising sorbent and flocculant. For purposes of present work Hexadecyltrimethylammonium bromide, Tetradecyltrimethylammonium bromide, and Carbethoxypendecinium bromide were used as selected cationic surfactants, Sodium dodecyl sulphate as anionic and TWEEN-20 as a non-ionic. The interactions between the individual components were studied by using a combination of dynamic light scattering (determination of the changes in particle size distributions), electrophoretic light scattering (zeta potential – stability investigation) and isothermic titration calorimetry (thermodynamic parameters of interactions) in titration mode of measurement. This set-up provided us the determination of the critical aggregation concentrations of the surfactant-humic system, which corresponded to its phase separation. Moreover, the interactions between the components were confirmed also by routine physico-chemical methods (e.g. thermogravimetry and Fourier transform infrared spectroscopy).  We believe that the outcomes of our work will help to shed a new light on the phenomenon of the formation of the interaction between surfactants and humic substances and will provide the crucial insight in the broader utilization of specific fractions humic substances as the universal sorbent for surfactants mainly from the waste waters.
The energetic electron instrument (IDEE) onboard the TARANIS spacecraft to search lightning-connected energetic electron populations
Authors: Prech Lubomir , Blelly Pierre-Louis , Devoto Pierre , Sauvaud Jean-Andre , Wong Kingwah , Orttner Guillaume , Baby Nathalie , Cermak Ivo
Published: March 2020

TARANIS (Tool for the Analysis of RAdiations from lightNIngs and Sprites) is a French CNES microsatellite dedicated to the study of the impulsive energy transfer between the Earth’s atmosphere and the space environment as widely observed above the active thunderstorm regions. After years of development and testing, the satellite is approaching to its launch (expected in June 2020). The comprehensive satellite scientific payload incorporates optical, field, and particle sensors including the energetic electron instrument (IDEE) with very high sensitivity and time resolution. Its main scientific tasks are: to measure high resolution energetic electron spectra (70 keV to 4MeV) and pitch angle distributions, to separate upward accelerated electrons and downward precipitated electrons, to detect burst of electrons associated with Terrestrial Gamma ray Flashes, to identify Lightning-induced Electron Precipitation (LEP), and to provide alert signals about high-energy electron bursts to other TARANIS experiments.  The aim of this contribution is to describe the final design and expected performance of the IDEE experiment, including the data products. We also want to show how we are going to enhance the today’s scientific knowledge of the thunderstorm related phenomena in synergy with other ground-based and space-born experiments.
Dusty plasma effects in the nighttime ionosphere of mars
Authors: Izvekova Yulia , Popel Sergey , Besedina Alina
Published: March 2020

A self-consistent consideration of the motion of dust particles in plasma systems in the atmosphere of Mars can lead to the detection of oscillations and waves, which, in particular, can be detected from the surface of the planet. The presence of local magnetic fields leads to significant inhomogeneities in the ionosphere of Mars, especially noticeable on the night side. On the night side of the ionosphere, there are areas of sharp increase in electron concentrations in areas where the lines of force of the magnetic field are perpendicular to the surface of the planet. In the areas where the magnetic field is parallel to the surface, the electrons of the solar wind do not penetrate the atmosphere and there is no ionization. Horizontal gradients of electron density on the night side can exceed 10 ^ 4 cm ^ -3 for several tens of kilometers. Such high plasma density gradients lead to local plasma transfer perpendicular to the external magnetic field, horizontal currents and electric fields are generated. Interaction of the plasma of the solar wind with a plasma containing dust particles can lead to the generation of high-frequency waves.

The work is supported by the Russian Science Foundation (project No 18-72-00119).
Spatio-temporal missing data reconstruction in satellite displacement measurement time series
Authors: Hippert-Ferrer Alexandre , Yan Yajing , Bolon Philippe
Published: March 2020

Time series analysis constitutes a thriving subject in satellite image derived displacement measurement, especially since the launching of Sentinel satellites which provide free and systematic satellite image acquisitions with extended spatial coverage and reduced revisiting time. Large volumes of satellite images are available for monitoring numerous targets at the Earth’s surface, which allows for significant improvements of the displacement measurement precision by means of advanced multi-temporal methods. However, satellite image derived displacement time series can suffer from missing data, which is mainly due to technical limitations of the ground displacement computation methods (e.g. offset tracking) and surface property changes from one acquisition to another. Missing data can hinder the full exploitation of the displacement time series, which can potentially weaken both knowledge and interpretation of the physical phenomenon under observation. Therefore, an efficient missing data imputation approach seems of particular importance for data completeness. In this work, an iterative method, namely extended Expectation Maximization - Empirical Orthogonal Functions (EM-EOF) is proposed to retrieve missing values in satellite image derived displacement time series. The method uses both spatial and temporal correlations in the displacement time series for reconstruction. For this purpose, the spatio-temporal covariance of the time series is iteratively estimated and decomposed into different EOF modes by solving the eigenvalue problem in an EM-like scheme. To determine the optimal number of EOFs modes, two robust metrics, the cross validation error and a confidence index obtained from eigenvalue uncertainty, are defined. The former metric is also used as a convergence criterion of the iterative update of the missing values. Synthetic simulations are first performed in order to demonstrate the ability of missing data imputation of the extended EM-EOF method in cases of complex displacement, gaps and noise behaviors. Then, the method is applied to time series of offset tracking displacement measurement of Sentinel-2 images acquired between January 2017 and September 2019 over Fox Glacier in the Southern Alps of New Zealand. Promising results confirm the efficiency of the extended EM-EOF method in missing data imputation of satellite image derived displacement time series.
The Drought & Flood Mitigation Service in Uganda – First Results
Authors: Westerbeeke Hermen , Bamanya Deus , Gibson George
Published: March 2020

Since 2017, the governments of Uganda and the United Kingdom have been taking an innovative approach to mitigating the impacts of drought and floods on Ugandan society in the DFMS Project. Recognising both that the only sustainable solution to this issue is the continued capacity development in Uganda’s National Meteorological and Hydrological Services, and that it will take time for this capacity development to deliver results, the Drought & Flood Mitigation Service Project developed DFMS, bringing together meteorological, hydrological, and Earth observation information products and making these available to decision-makers in Uganda.

After the DFMS Platform was designed and developed in cooperation between a group of UK organisations that includes the Met Office and is led by the REA Group and five Ugandan government agencies including UNMA, led by the Ministry of Water and Environment (MWE), 2020 saw the start of a 2.5-year Demonstration Phase in which UNMA, MWE, and the other agencies will trial DFMS and DFMS will be fine-tuned to their needs. We will be presenting the first experiences with DFMS, including how it is being used related to SDG monitoring, and will showcase the platform itself in what we hope will be a very interactive session.

DFMS is a suite of information products and access only requires an Internet-connected device (e.g. PC, laptop, tablet, smart phone). Data and information are provided as maps or in graphs and tables, and several analysis tools allow for bespoke data processing and visualisation. Alarms can be tailored to indicate when observed or forecast parameters exceed user-defined thresholds. DFMS also comes with automatic programmable interfaces allowing it to be integrated with other automatic systems. The DFMS Platform is built using Open Source software, including Open Data Cube technology for storing and analysing Earth Observation data. It extensively uses (free) satellite remote sensing data, but also takes in data gathered in situ. By making the platform scalable and replicable, DFMS can be extended to contain additional features (e.g. related to landslides or crop diseases) or be rolled out in other countries in the region and beyond.
The potential of a synergestic lidar and sunphotometer retrieval for the characterization of a dust event over Finokalia and for aerosol model evaluation
Authors: Konsta Dimitra , Tsekeri Alexandra , Solomos Stavros , Lopatin Anton , Goloub Philippe , Dubovik Oleg , Amiridis Vassilis , Nastos Panagiotis
Published: March 2020

The ability of three-dimensional dust models to accurately represent the dust life cycle is crucial for describing dust effects on radiation and clouds and for reducing the uncertainties on these processes. To improve the reliabilty of dust models, it is therefore imperative to carry out thorough evaluations of the dust properties. Dust optical and microphysical properties are accurately accessed through groundbased observations: multiwavelength lidars and sunphotometers. In this study we use the Generalized Retrieval of Atmospheric and Surface Properties (GRASP) data algorithm that combines the lidar and sunphotometer data to retrieve dust properties. GRASP is applied on a Saharan dust episode over Finokalia, Crete in Greece, on 14 May 2017. More precisely the measurements from PollyXT lidar participating in the European Aerosol Research Network (EARLINET) and the CIMEL sunphotometer participating in Aerosol Robotic Network (AERONET) are synergetically combined using the GRASP algorithm. The dust event is fully characterised through the retrieval of dust optical and microphysical properties. The retrieved properties are found to be in good agreement with the initial measurements from the AERONET sunphotometer and the lidar. Then the aforementioned tools are used to evaluate the performance of the regional dust model NMME-DREAM that has been developed to simulate and predict the atmospheric cycle of mineral dust aerosols. It is shown that the model has problems in simulating the high dust concentration values at low levels, probably due to the low spatial resolution of the model that causes difficulties in capturing the orography and the downdrafts winds.
Assessing and monitoring the vulnerability to drought and climate anomalies of Mediterranenan oak forests by using NDVI
Authors: Castellaneta Maria , Rita Angelo , Camarero J. Julio , Colangelo Michele , Nolè Angelo , Ripullone Francesco
Published: March 2020

Several die-off episodes related to heat weaves and drought spells have evidenced the high vulnerability of Mediterranean oak forests. These events consisted in the loss in tree vitality and manifested as growths decline, elevated crown transparency (defoliation) and rising tree mortality rate. In this context, the changes in vegetation productivity and canopy greenness may represent valuable proxies to analyze how extreme climatic events trigger forest die-off. Such changes in vegetation status may be analyzed using remote-sensing data, specifically multi-temporal spectral information. For instance, the Normalized Difference Vegetation Index (NDVI) measures changes in vegetation greenness and is a proxy of changes in leaf area index (LAI), forest aboveground biomass and productivity. In this study, we analyzed the temporal patterns of vegetation in three Mediterranean oak forests showing recent die-off in response to the 2017 severe summer drought. For this purpose, we used an open-source platform (Google Earth Engine) to extract collections of MODIS NDVI time-series from 2000 to 2019. The analysis of both NDVI trends and anomalies were used to infer differential patterns of vegetation phenology among sites comparing plots where most trees were declining and showed high defoliation (test) versus plots were most trees were considered healthy (ctrl) and showed low or no defoliation. Here we discuss: i) the likely offset in NDVI time-series between test- versus ctrl- sites; and ii) the impact of summer droughts  on NDVI.

Keywords: climate change, forest vulnerability, time series, remote sensing.
Impact of Soil Moisture Initialization on Temperature Extreme Detection in the context of Regional Climate Modeling
Authors: García-Valdecasas Ojeda Matilde , Rosa-Cánovas Juan José , Romero-Jiménez Emilio , Yeste Patricio , Gámiz-Fortis Sonia R. , Castro-Díez Yolanda , Esteban-Parra María Jesús
Published: March 2020

Land surface-related processes play an essential role in the climate conditions at a regional scale. In this study, the impact of soil moisture (SM) initialization on regional climate modeling has been explored by using a dynamical downscaling experiment. To this end, the Weather Research and Forecasting (WRF) model was used to generate a set of high-resolution climate simulations driven by the ERA-Interim reanalysis for a period from 1989 to 2009. As the spatial configuration, two one-way nested domains were used, with the finer domain being centered over the Iberian Peninsula (IP) at a spatial resolution of about 10 km, and nested over a coarser domain that covers the Euro-CORDEX region at 50 km of spatial resolution.

The sensitivity experiment consisted of two control runs (CTRL) performed using as SM initial conditions those provided by ERA-Interim, and initialized for two different dates times (January and June). Additionally, another set of runs was completed driven by the same climate data but using as initial conditions prescribed SM under wet and dry scenarios.

The study is based on assessing the WRF performance by comparing the CTRL simulations with those performed with the different prescribed SM, and also, comparing them with the observations from the Spanish Temperature At Daily scale (STEAD) dataset. In this sense, we used two temperature extreme indices within the framework of decadal predictions: the warm spell index (WSDI) and the daily temperature range (DTR).

These results provide valuable information about the impact of the SM initial conditions on the ability of the WRF model to detect temperature extremes, and how long these affect the regional climate in this region. Additionally, these results may provide a source of knowledge about the mechanisms involved in the occurrence of extreme events such as heatwaves, which are expected to increase in frequency, duration, and magnitude under the context of climate change.

Keywords: soil moisture initial conditions, temperature extremes, regional climate, Weather Research and Forecasting model

Acknowledgments: This work has been financed by the project CGL2017-89836-R (MINECO-Spain, FEDER). The WRF simulations were performed in the Picasso Supercomputer at the University of Málaga, a member of the Spanish Supercomputing Network.
Development of a Physics-Based Prototype Model Chain for Solar Energetic Particle Acceleration and Transport Forecasting for the Inner Heliosphere
Authors: Kozarev Kamen , Miteva Rositsa , Dechev Momchil , Zucca Pietro
Published: March 2020

We present the project SPREAdFAST – Solar Particle Radiation Environment Analysis and Forecasting - Acceleration and Scattering Transport. This investigation fulfills a vital component of the space weather requirements of ESA’s Space Situational Awareness program by contributing to the capability to protect space assets from solar activity space radiation. It will allow for producing predictions of SEP fluxes at multiple locations in the inner heliosphere, by modelling their acceleration at Coronal Mass Ejections (CMEs) near the Sun, and their subsequent interplanetary transport using a physics-based, data-driven approach. The system prototype will incorporate results from our scientific investigations, the modification and linking of existing open source scientific software, and its adaptation to the goals of the proposed work. It will incorporate a chain of data-driven analytic and numerical models, for estimating: coronal magnetic fields; dynamics of large-scale coronal (CME-driven) shock waves; energetic particle acceleration; scatter-based (not simple ballistic), time-dependent SEP propagation in the heliosphere to specific time-dependent locations.