bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanism of Sand-Mud Transition Dynamics at an Artificial Beach Based on Horizontal and Vertical Sedimentary Modeling
Authors: Liang Huidi , Zhu Xiao , Chen Wei , Shi Lianqiang
Published: February 2023

Sandy-Muddy Transitional beaches (SMT-beaches), which consist of a narrow high-tide sandy beach and wide low-tide mudflat, are well developed in the embayment worldwide (George and Hill, 2008; Zhao et al., 2020). These SMT-beaches provide a large tourism potential, especially along the muddy coasts of East China where are an extreme lack of excellent sandy beaches.  Because of the differences in the physical, geological and biological processes on the two sides of the beach, morphological variations in an SMT-beach are expected to coincide with the Sand-Mud Transition (SMT) boundary migrations (George et al., 2007). The movements of the SMT are closely related to the hydrodynamics forcing, sediment supply and morphology based on previous observations (Guo et al., 2021; Zhao et al., 2020), however, numerical modeling studies unraveling the underlying mechanisms remain rare.    With an artificial sandy beach of Dongtou island, China as a reference site, this study explores the roles of tidal ranges and wave climate on SMT dynamics and sediment sorting using a morphodynamic model that couples hydrodynamics, sediment transport and morphological change. A fair comparison between model simulation and sediment cores is first conducted to validate the performance of morphodynamic model. Then horizontal and vertical sedimentation against multiple hydrodynamic variables is evaluated to reveal the mechanism of the SMT dynamics. This study will gain a more in-depth mechanistic understanding of the morphodynamic processes of SMT-beaches and provide a scientific facet to make sustainable management strategies for potential future nourishment on the muddy coast. ReferenceGeorge, D.A., Hill, P.S., Milligan, T.G., 2007. Flocculation, heavy metals (Cu, Pb, Zn) and the sand-mud transition on the Adriatic continental shelf, Italy. Continental Shelf Research 27,475–488.George, D.A., Hill, P.S., 2008. Wave climate, sediment supply and the depth of the sand–mud transition: A global survey. Marine Geology 254, 121-128.Guo, J., Shi, L., Chen, S., Bruno, C, Chang, Y., Cheng, W., 2021. Sand-mud transition dynamics at embayed beaches during a typhoon season in eastern China. Marine Geology. 441, 106633.Zhao, S., Cai, F., Qi, H., Zhu, J., Zhou, X., Lei, G., Zheng, J., 2020. Contrasting sand-mud transition migrations in estuarine and bay beaches and their potential morphological responses. Geomorphology 365, 107243.
Assessment of agronomic adaptation strategies to climate change in a Mediterranean watershed with SWAT+
Authors: Villani Lorenzo , Castelli Giulio , Addisu Yimer Estifanos , Nkwasa Albert , Penna Daniele , van Griensven Ann , Bresci Elena
Published: February 2023

The Mediterranean region is considered a hotspot for climate change as it is expected to face more severe impacts compared to other regions of the world. To better understand these impacts and plan more effective adaptation strategies, integrated assessments should consider not only biophysical aspects, but also social, political, and economic ones. Plenty of models are available to simulate these various aspects, but certainly, the more models are included, the higher the complexity, which severely affects the reproducibility of the studies. Even when considering only biophysical aspects, related for example to water and food security, individual crop and/or hydrological models have intrinsic limitations. Integrated, distributed, agro-hydrological models such as the Soil and Water Assessment Tool (SWAT) might be the solution to overcome some of these drawbacks, including the point-scale nature of crop-growth models.We applied the SWAT+ model in a medium-sized agricultural watershed in Central Italy, the Ombrone watershed, in order to comprehensively assess climate change impacts on crop production and water management and evaluate autonomous agronomic adaptation strategies. By forcing SWAT+ with five bias-corrected EURO-CORDEX climate models, we assessed future precipitation and temperature in the study area. Moreover, we simulated the fluxes of different water balance components and evaluated how they were affected by the increasing CO2 concentration. Then, we simulated future crop yield and water footprint of three representative crops - durum wheat, sunflower and irrigated maize - and evaluated the adaptive capacity of the agricultural systems by simulating simple adaptation strategies such as shifting sowing dates and applying supplemental irrigation. Finally, we estimated the effects of these adaptation strategies on water balance components.While the temperature was predicted to increase, future precipitation showed much more uncertainty. Furthermore, considering the CO2 fertilization effect enhanced the uncertainty about future aridity conditions, with variables such as potential evapotranspiration that varied up to 50% when considering constant or increasing CO2 concentration. Crop yield was negatively affected mainly by the reduction of crop cycle length caused by increased temperatures, but with adaptation strategies it was possible to reduce losses or even obtain higher production. Finally, management changes such as the inclusion of cover crops in the crop rotation have a significant impact on some water balance components that cannot be neglected. The results of this study show the increasing need to adapt to climate change impacts in the Mediterranean cultivated catchments.
Effects of the realistic vegetation cover on predictions at seasonal and decadal time scales
Authors: Di Carlo Emanuele , Alessandri Andrea , van Oorschot Fransje , Cherchi Annalisa , Corti Susanna , Balsamo Giampaolo , Boussetta Souhail , Stockdale Timothy
Published: February 2023

Vegetation is a relevant and highly dynamic component of the Earth System controlling, amongst others, surface roughness, albedo and evapotranspiration; its variability shows changes in seasons, interannual, decadal and longer timescales. In this study, we investigate the effects of improved representation of vegetation dynamics on climate predictions at different timescales: seasonal and decadal. To this aim, the latest generation satellite datasets of vegetation characteristics have been exploited, and a novel and improved parameterization of the effective vegetation cover has been developed. The new parameterization is implemented in the land surface scheme HTESSEL shared by two state-of-the-art Earth system models: ECMWF SEAS5 and EC-Earth3. The former model is used for sensitivity at seasonal timescale, while the latter is used for sensitivity at decadal timescale.Both seasonal and decadal experiments show considerable sensitivity of models' surface climate bias with large effects on December-January-February (DJF) T2M, mean sea level pressure and zonal wind over middle-to-high latitudes. Consistently, a significant improvement in the skill for DJF T2M is found, especially over Euro-Asian Boreal forests. In seasonal experiments, this improvement displays a strong interannual coupling with the local surface albedo. From the region with the most considerable T2M improvement, over Siberia, originates a large-scale effect on circulation encompassing Northern Hemisphere middle-to-high latitudes from Siberia to the North Atlantic. As a result, in seasonal experiments, the correlation between the model NAO index against the ERA5 NAO index improves significantly.These results show a non-negligible effect of the vegetation cover on the general circulation, especially for the northern hemisphere and on the prediction skill.
High-resolution hybrid atomic quantum gravimeter with real-time vibration compensation
Authors: Amorosi Anthony , Teloi Mayana , Amez-Droz Loïc , Faure Laura , Ménoret Vincent , Rosenbusch Peter , Thibaut Brieux , Collette Christophe
Published: February 2023

Over the past decades, gravimeters based on different working principles have been developed, such as superconducting gravimeters, spring gravimeters or interferometric gravimeters. Their ability to measure local changes in gravitational acceleration with a very high level of sensitivity makes these instruments widely used in fundamental physics, inertial navigation and geophysics. Recently, quantum gravimeters based on cold atom interferometry have demonstrated some of the best resolution and stability. The atomic quantum gravimeter (AQG) from iXblue is a drift-free absolute gravimeter with a sensitivity of 750 nm/s^2 at 1 sec and a long-term stability that reaches 10 nm/s^2, currently standing as a top-class industry-standard instrument [1]. However, due to its cyclic operation principle, the sensor is subject to dead times and concentrates on low-frequency variations (DC – 1 Hz). In addition, ground vibrations often overshoot the atom interferometer dynamic range. These issues have been demonstrated to be overcome by combining the quantum gravimeter with a classical accelerometer that senses ground accelerations and decouples the atom interferometer from them, so creating a hybrid quantum-classical sensor [2]. We present the hybridization of an Atomic Quantum Gravimeter with a custom-made optical accelerometer. The accelerometer has been specifically designed to optimally reject ground vibrations in the sensitivity range of the atom interferometer in real time. It consists of a force-feedback interferometric inertial sensor with a bandwidth from 10 s to 100 Hz and sub-picometer resolution. The accelerometer mechanics features fused-silica flexures, allowing to reach a 2.8 Hz natural frequency and a mQ-product of 1100 kg in a compact, 10x10x10 cm3, design. The hybridization of the quantum gravimeter with the optical accelerometer is expected to push down the noise floor of both sensors, ultimately hitting the quantum projection noise of the Absolute Quantum Gravimeter, being 350 nm/s2 at 1 sec. This improvement would therefore open new perspectives for applications of the quantum gravimeter, such as Newtonian-Noise estimation or seismic isolation.[1] Ménoret et al, Gravity measurements below 10-9g with a transportable absolute quantum gravimeter, Scientific Reports 8, 12300 (2018)[2] Merlet et al, Operating an atom interferometer beyond its linear range, Mtrologia 46, 87 (2009)[3] Lautier et al, Hybridizing matter-wave and classical accelerometers, Applied Physics Letters 105, 144102 (2014)
Insect herbivory have significantly altered BVOC emissions, SOA concentration and radiative forcing over Fennoscandian birch forest
Authors: Tang Jing , Wang Hui , Cai Zhanzhang , Guenther Alex , Rinnan Riikka , Olsson Per-Ola , Borchmann Rikke Lauge , Davie-Martin Cleo Lisa , Schurgers Guy , Ren Zhengchao , Rieksta Jolanta , Li Tao
Published: February 2023

Over Fennoscandian mountain birch forest region, there are increased attacks of geometrid moth larvae. These herbivores can change forests from a carbon sink to a carbon source. When moths start to chew on leaves, large quantities of biogenic volatile organic compounds (BVOCs) are released. Herbivory-induced BVOC emissions have been observed and quantified at a few sites over Fennoscandian mountain birch forest, but we know very little of their potential regional implications for atmospheric processes.In this work, we extracted birch defoliation information based on MODIS leaf area index (LAI) for an outbreak year 2012, and together with field-observed relationship between leaf defoliated level and changes in emissions, we modelled herbivory-induced BVOC emissions at regional scale using MEGAN. Taking a step further, we fed MEGAN-modelled BVOC emission data with or without considering herbivory impacts to a two-way coupled WRF-CMAQ system to dynamically assess the impacts of these emissions on the atmospheric chemistry and climate system .During the whole growing season of 2012, the defoliation at some MODIS grids can be as high as 90%, and the large defoliation mainly occurs in June and July. For t-β-ocimene, Other Monoterpenes, Stress and Other compound groups, herbivory contributes to more than 30, 8, 5 and 16 times the increase in the seasonal sum for the defoliated regions. For terpenes, herbivory increased monthly emissions up to 3 times for June and July. The reduction of emissions caused by herbivory-caused decrease in LAI is much smaller than the herbivory-induced increase. We also found strong impacts of herbivory-induced BVOC emissions on downward shortwave radiation and cloud radiative forcing.This is the first time we can link all these components, i.e., satellite monitoring of leaf defoliation, in-situ observation, ecosystem and atmospheric modelling together to answer the research questions related to the regional importance of insect herbivory on atmospheric composition and climate.
Overview of the ACROSS Campaign near Paris in Summer 2022
Authors: Cantrell Christopher , Michoud Vincent , Doussin Jean-Francois , Formenti Paola , Cirtog Manuela , Coll Patrice , Di Antonio Ludovico , Di Biagio Claudia , Gratien Aline , Picquet-Varrault Benedicte , Siour Guillaume ,   ACROSS Measurement and Modeling Team
Published: February 2023

ACROSS (Atmospheric ChemistRy Of the Suburban foreSt) is an integrative, innovative, multi-scale project within the “Make Our Planet Great Again” (MOPGA) initiative designed to advance understanding of the fate of the photochemical processing of urban and biogenic air mass mixtures in the Paris region. An ACROSS hypothesis is that the anthropogenic-biogenic air mass mixing leads to changes in the production of oxygenated volatile organic compounds (VOCs) whose properties alter their importance in incorporation into secondary organic aerosols (SOA) and their roles in production of ozone and other relevant secondary species. A likely important factor is NOx transport to suburban biogenic environments and the resulting modification of key chemical processes.The key highlight of ACROSS was an intensive, multi-platform measurement campaign that took place in the summer of 2022. The campaign included measurements from multi-instrumented ground sites located in the urban, rural, and semi-rural Paris region including a 40-meter tower and from the ground in the Rambouillet suburban forest southwest of Paris, and airborne regional observations following the urban plume downwind of Paris and areas within 150 km (coordinated with other projects in the framework of the PANAME initiative). As the analysis proceeds, the data collected from this campaign will provide a unique snapshot of the properties that are characteristic of combinations of urban and biogenic air masses around one of the largest European megacities. This new knowledge will contribute to advancement of our understanding at the process level and will lead to the ability to better represent such complex systems in numerical models, ultimately resulting in improved capability to predict the impacts on air quality, regional climate, and global climate change.This presentation consists of a summary of the campaign organization and measurements. Some preliminary findings from the analysis of the observations in the early stages are shown as a complement to other, more focused evaluations that are given at this meeting.
Spontaneous Formation of OH Radicals in the Air-Water Interface of Water Droplets
Authors: Angelaki Maria , Carreira Mendes Da Silva Yoan , George Christian
Published: February 2023

Water covers about 71 percent of the Earth’s surface (i.e., oceans, glaciers) and it is crucial for all the biological systems. Although bulk water is inert, water microdroplets provide a favourable environment for chemical processes. The investigation and the understanding of the physico-chemical processes that occur in the atmospheric aerosols is of great importance, while aerosols is well-known that have an adverse effect in air-quality, climate and public health. In the air-water interface the presence of a strong electric field can lead to the acceleration of chemical reactions and initiate spontaneous reduction of organic compounds. Our study is focusing on the spontaneous H2O2 production at the interface of water droplets, which occurs via the recombination of the hydroxyl radicals that are formed via the dissociation of hydroxyl ions, while other pathways cannot be excluded.  H2O2 may play a key role in the oxidation of atmospheric aerosols and therefore, it may alter the oxidation capacity by increasing the production of radicals.Within this framework, a thorough laboratory study, using state-of-the-art instrumentation has been carried out. Two different types of experiments were performed, where the H2O2 and thus the OH production was measured either directly or indirectly by using sensitive water-soluble fluorescent probes. Aqueous microdroplets, in a range of diameter 0.1 to 10 µm were generated by nebulizing salted solutions inside a glass reactor. These particles were then collected after 4 hours reaction time and the liquid phase H2O2 was measured by using an H2O2 analyser. During our experiments, an Optical Particle Counter was connected in order to monitor the size distribution and the number of the particles. To extend our understanding in the processes that occur at the interface, different types of salts were selected (NH4Cl, Na2SO4 and CaSO4) in order to investigate the way that different ions of different valence affect the H2O2 production. A correlation between the size distribution and the hydrogen peroxide concentration was also performed. In order to verify the OH production, salted solutions containing terephalic acid (TA) were also nebulised inside the reactor. The collected droplets were analysed via fluorescent spectroscopy where the 2-hydroxyterephthalic acid (TAOH), product of the reaction of TA with OH radicals, was observed. TAOH was also observed in the particle phase in a size range of 1–5 µm.All the experiments provide evidence that H2O2 is produced in the air-water interface of microdroplets at a range of (1–7)×10-2 µM, which depends on the size distribution, the concentration of the solution and the type of salt. Results from this study are expected to significantly improve our insight on the processes that occur in atmospheric droplets and to assess the contribution of this OH radical source in total atmospheric budget.
The introduction of ITRF2020 in global positioning applications
Authors: Matonti Francesco , Miller Adam , Wnuk Joanna
Published: February 2023

With the integration of positioning solutions into mass-production autonomous driving systems, together with the ever-increasing demand for global positioning applications the use of a global reference frame is now a requirement that global correction service providers need to support and deliver, whilst still maintaining support of local (regional) official reference frames. To maintain high precision of the GNSS network we perform a daily solution, which is computed based on precise orbits and following the guidelines of the EPN Analysis Centres. Using the daily solutions, we are estimating the linear velocity of reference stations within GNSS networks and are also considering jumps due to equipment changes. The estimated velocities give the opportunity to monitor the long-term stability of the network as well as the quality of reference station coordinates. The transition between ITRF2014 and ITRF2020 on a large GNSS reference stations worldwide, including the computation of the HxGN SmartNet GNSS network consisting of more than 5300 GNSS reference stations, will be investigated to evaluate the impact that this could have on the users using the correction services.The daily solution and monitoring of GNSS networks, such as HxGN SmartNet, is executed by the Leica Geosystems solution named Leica CrossCheck, which is based on Bernese GNSS software. Leica CrossCheck is capable to monitor GNSS networks of all scales.KEYWORDS: GNSS reference station network, Bernese GNSS 5.4, Leica CrossCheck, Leica GNSS Spider, HxGN SmartNet, Leica GeoMoS Now!References:Dach, R., S. Lutz, P. Walser, P. Fridez (Eds); 2015: Bernese GNSS Software Version 5.2. User manual, Astronomical Institute, Universtiy of Bern, Bern Open Publishing. DOI: 10.7892/boris.72297; ISBN: 978-3-906813-05-9.
POST-QUARRY LANDSCAPE. 3D representation and topology alteration as a tool for landscape recovery and secondary raw material procurement in the context of granite quarries.
Authors: Tinti Lorenzo , Lobosco Gianni , Medici Marco , Aquilano Antonello , Emanueli Luca , Vaccaro Carmela
Published: February 2023

At the end of their activity, quarries require environmental recovery in order to ensure a new balance between the quarry site and its physical and ecological context. Moreover, the activities of the ornamental rock extraction produce a large amount of extraction waste which profoundly modify the site's topography in an increasing way as the accumulations are formed progressively during the quarrying process. These wastes can be either recycled as secondary raw materials (e.g., in the context of the ceramic industry) or reused within the quarry site to mould a new topography and a new landscape as a result. Earth sciences and landscape architecture should constitute the disciplinary basis on which to develop the recovery project associated with the supply of secondary raw materials and the environmental improvement of the quarry site. This contribution discusses the case study of the Buddusò granite quarry (northern Sardinia, Italy), where a design methodology based on topology alteration of the site was applied. Through 3D survey and parametric design, it is possible to calculate the waste volumes within the excavation site and estimate how much and in what way the waste material can be recycled and reused. The first phase of the process consists of taking orthophotographic images by drone with subsequent georeferencing through G.P.S. points acquisition. After processing the acquired data, the topography of quarry volumes is recreated in an explorable 3D model. The last phase concerns the design management of the site topology through the application of parametric design tools. The objective is to create an adaptive project based on parameters such as: the balance between excavation and fill volumes; the recycling potential of waste material; the dynamics of water runoff; the ecological and ecosystem site potential; the site accessibility. The presented design methodology can be carried out either in the pre-quarry phase and/or during the quarry's operation, which allows an a priori assessment of what the future landscape will look like as a consequence of quarrying activities and subsequent site recovery. In practical terms, the presented methodology become a preliminary tool for the assessment of landscape evolution scenarios and ensures that the extraction cycle can be completely closed by reintegrating waste volumes into the recovery process. 
Maize roots under mechanical stress induce increased ethylene concentration in the soil gas phase
Authors: Phalempin Maxime , Lippold Eva , Brauweiler Felix , Apelt Bernd , Würsig Henrike , Tarkka Mika , Schlüter Steffen , Vetterlein Doris
Published: February 2023

Mechanical stress induced by soil compaction affects drastically root system architecture and the morphology of individual root segments. Typical effects of mechanical stress on the root responses include decreased root elongation, increased radial thickening and sloughing of cap cells. Many studies have established a link between the mechanical stress encountered by roots (generated in triaxial cells or by restricting root growth with a barrier) and the gaseous plant hormone ethylene; the data suggests that ethylene acts as an endogenous root growth regulator. To the best of our knowledge however, none of the studies on the ethylene and mechanical stress feedback mechanisms measured ethylene concentrations under realistic soil conditions, i.e., in the soil gas phase and over a long period of time. In this study, we aimed at filling this knowledge gap and set up an experiment which allowed to measure ethylene concentration directly in the soil gas phase with passive diffusive samplers and for maize plants subjected to different levels of soil compaction over a period of 21 days in repacked soil columns in the laboratory. With the help of X-ray computed tomography, we investigated the spatiotemporal patterns of ethylene concentrations in the vicinity of roots, in order to assess which type of roots act as a major source of ethylene in the soil. In accordance with the literature, soil compaction induced a significant increase in ethylene concentration in the soil gas phase, which impacted root growth by reducing significantly the growth of fine roots and increasing the share of thicker roots. A visual inspection of the X-ray CT images at different time points of gas sampling showed that high concentrations of ethylene (i.e., above the third quartile of the distribution) were not strictly ascribable to the abundance or type of roots in the vicinity of a probe. Yet, the highest concentrations of ethylene were recorded on the occasions where roots were present close to a probe. The sampling depths and time of sampling had no or very little effect on the measured ethylene concentrations. Our results suggest that ethylene was diffusing rather homogeneously in the soil columns and that microbial activity was also responsible for a good fraction of the ethylene production. Future experiments are planned to assess the contribution of microbes to the total ethylene production.
The technical relationship between vertical greening and built heritage
Authors: De Groeve Marie , Kale Eda , Orr Scott Allan , De Kock Tim
Published: February 2023

Built heritage is rich in cultural and economic values and is an essential part of urban environments. These buildings are abundant in city centres that have been the site of development for several centuries. This has produced a dense environment, exhibiting strong urban heat island effects. Green initiatives are increasingly being implemented to mitigate current climate stressors and improve the health and well-being of residents. However, built heritage is often excluded from these approaches due to concerns about their impact on materials and structural integrity, which is poorly understood. This research scopes the technical compatibility of vertical greening with built heritage in an urban environment regarding the degradation of historic building materials. Vertical greening here is understood to include plants, rooted in the ground, growing along a vertical surface by either attaching themselves to the façade or trellising. Investigating the impact of vertical greening on the local microclimate by monitoring case studies, lab experiments and analysing current literature can help us understand how vertical greening affects common forms of degradation caused by salts, frost, bio-activity and air pollution. Each method has its own approach to understanding the relationship of vertical greening with built heritage and is complementary to the others. The lab experiments explore the three main factors impacted by vertical greening such as temperature and relative humidity, incoming solar irradiation and precipitation exposure. Temperature and relative humidity are inseparably connected with each other and therefore analysed together. The impact of vertical greening on the aforementioned environmental parameters is investigated separately to provide better insights into those microclimatic changes that determine the risk of weathering of historic building materials.
GPU-based finite-difference solution of 3-D stress distribution around continental plateaus in spherical coordinates
Authors: Macherel Emilie , Podladchikov Yuri , Räss Ludovic , Schmalholz Stefan M.
Published: February 2023

On Earth, different geodynamic features form in response to a tectonic event. Continental plateaus, such as the Tibetan Plateau, are formed in a collisional environment and they are characterized by an unusually large crustal thickness, which generates lateral variations of gravitational potential energy per unit area (GPE). These GPE variations cause the thickened crust to flow apart and thin by gravitational collapse. Although plateau and lowland are in isostatic equilibrium, the lateral GPE variations must be balanced by horizontal differential stresses, which prevent the plateau from flowing-apart instantaneously. However, the magnitude and distribution of differential stress around plateau corners for three-dimensional (3-D) spherical geometries relevant on Earth remain disputed. Due to the ellipticity of the Earth, the lithosphere is mechanically analogous to a shell, characterized by a double curvature. Shells exhibit fundamentally different mechanical characteristics compared to plates, having no curvature in their undeformed state. Understanding the magnitude and the spatial distribution of strain, strain-rate and stress inside a deforming lithospheric shell is thus crucial but technically challenging. Resolving the stress distribution in a 3-D geometrically and mechanically heterogeneous lithosphere requires high-resolution calcuations and high-performance computing.Here, we present numerical simulations solving the Stokes equations under gravity. We employ the accelerated pseudo-transient finite-difference (PTFD) method, which enables efficient simulations of high-resolution 3-D mechanical processes relying on a fast iterative and implicit solution strategy of the governing equations. The main challenges are to guarantee convergence, minimize the iteration count and ensure optimal execution time per iteration. We implemented the PTFD algorithm using the Julia language. The Julia packages ParallelStencil.jl and ImplicitGlobalGrid.jl enable optimal parallel execution on mulitple CPUs and GPUs and ideal scalability up to thousands of GPUs.The aim of this study is to quantify the impact of different lithosphere curvatures on the resulting stress field. To achieve this, we use a simplified plateau geometry and density structure implemented in a spherical coordinate system. The curvature is modified by varying the radius of the coordinates system, without altering the initial geometry. We particularly focus on stress magnitudes and distributions in the corner regions of the plateau.
The ethics of volcano geoengineering
Authors: Mani Lara , Cassidy Mike , Sandberg Anders
Published: February 2023

Volcano engineering is the practice of altering the state of volcanic systems and/or volcanic eruptions to exploit them or mitigate their risk. Past and current examples of volcano engineering are limited but include drilling crater walls to drain volcanic lakes, channeling and bombing lava flows, siphoning off CO2 rich volcanic lakes, and cooling lava flows with seawater. There have also been several incidental examples of drilling into magma reservoirs in search for geothermal resources in Hawaii, Iceland, and Kenya. While not causing anything more damaging than the loss of drill bits or forcing the use of alternative holes, this demonstrates that humans are increasingly able to reach volcanic plumbing systems. As the pursuit of high temperature and enhanced geothermal energy increases as the world strives for renewable energy and critical metal resources, it is also likely that such contacts will become more common. We must accept, therefore, that despite the controversial nature of this topic, geoengineering of volcanic systems is an inevitable consequence of such exploration in the coming century. Since we possess the technological and engineering potential to perturb volcanic systems, the question we ask here is, should we? Do we have the scientific knowledge to do so? What are the potential benefits to future humanity? And, what are the ways it could do more harm than good? We highlight that while volcano geoengineering has significant potential benefits, the risks and uncertainties are too great to justify its use in the short term. Even if we do not decide to conduct volcano geoengineering, we believe there is a strong ethical case to support research into the efficacy and safety of volcano geoengineering going forwards. In this work, we lay out a series of protocols and practices based on the ethical arguments to be followed should humanity decide to conduct volcano geoengineering in the future.
The Petrinja earthquake series located and visualised using machine learning
Authors: Sindija Dinko , Ammirati Jean-Baptiste , Mustac Brcic Marija , Stipcevic Josip , Hetenyi Gyorgy
Published: February 2023

Earthquake detection and phase picking are crucial steps in the analysis of earthquakes. With the increasing number of seismic instruments available, large amounts of seismic data are generated, requiring the use of automatic algorithms to process earthquake series and to include events that would not be discovered with manual approaches. The Petrinja earthquake series started with local magnitude ML5.0 earthquake on December 28, 2020, followed by ML6.4 earthquake one day later. In the two years of this earthquake series, human analysts picked a total of 16,000 earthquakes smaller than M2.0, 1528 with magnitudes M2.0-2.9, 156 with magnitudes M3.0-3.9, 17 with magnitudes M4.0-4.9, 2 with magnitudes M5.0-5.9 and one earthquake with magnitude greater than M6.0. While the seismic network at the onset of this sequence counted only a few instruments in the epicentral area, the rapid aftershock deployment of 5 stations in the near vicinity of the fault zone, and the further gradual yet still remarkable growth of the seismic network to more than 50 instruments, produced an extraordinary amount of data, which are perfectly suited for employing machine learning (ML) methods for seismic phase picking and earthquake detection.In this study we present application of various ML methods to the Petrinja earthquake series. We also compare how the results change when we train a model using a subset of data from this earthquake series. Our results show that these machine learning methods are promising approaches for accurately detecting and picking phases in such earthquake series, and also delineate tectonic features responsible for generating them.
Radon risk mitigation in urban environments: experiences from active monitoring
Authors: Soldati Gaia , Ciaccio Maria Grazia , Piersanti Antonio , Cannelli Valentina , Galli Gianfranco
Published: February 2023

The primary stone building material of ancient Rome from its initial settlement until recent times is constituted by the tuff; easy to cut, resistant to weathering, and an effective thermal insulator, with the disadvantage of a significant radionuclide content. An accurate monitoring of indoor radon in workplaces and residential dwellings constitutes a first step towards mitigating the exposure to the population. Since radon diffusion dynamics involves complex interactions among many environmental parameters on different time scales, a proper assessment of radon concentration variations can be better achieved by means of active monitoring approaches. We present here the results of continuous measurements conducted in 35 residential dwellings located in the municipality of Rome and its suburban area, and in a public building and workplace: the geophysical museum of Rocca di Papa.The use of active devices makes it possible to discriminate between average indoor radon measured during the day, when workers and visitors are more likely present, and overnight, more relevant for the exposure of residents. Collecting long time series of radon concentration enables us to identify fluctuations over seasonal scales, with radon generally decreasing in the warm season. The simultaneous tracking of different floors of the same building shows an inversion of the dynamics of gas convection during the warm season compared to the cold one, likely depending on the chimney effect. Monitoring different rooms of the same dwelling reveals that values of gas concentration may greatly differ, indicating the importance of ventilation and/or heating system. Considering several dwellings allows us to question the general belief of a constantly higher exposure of the lowest floors to the indoor radon risk with respect to elevated floors (radon would enter mainly through foundation walls). Finally, the clustering of houses with high indoor radon levels in the historic center of Rome indicates the influence of geogenic radon and of building characteristics like age, typology, and construction materials.With so many endogenous and exogenous factors affecting the healthiness of indoor environments in terms of radon concentration, a proper assessment of health hazard requires the knowledge of the dynamics of the gas generation and transport inside the buildings, and of its temporal fluctuations; our analysis provides the instruments to disclose the characteristics of such dynamics, with the final goal to select the most suitable preventive measures to reduce radon exposure. 
High-resolution imaging of sedimentary basins in New Zealand’s fjords using boomer-sourced multi-channel seismic reflection data
Authors: Gorman Andrew , Wilson Gary , Moy Chris , Riesselman Christina , Beagley Jackson , Gilmer Greer , Dagg Bob , Bowman Hamish
Published: February 2023

Fiordland, on the southwest coast of New Zealand’s South Island, hosts 15 distinct fjords that extend up to 40 km inland from the Tasman Sea into mountainous terrain consisting primarily of hard crystalline igneous and metamorphic rocks. All of these fjords have seaward entrance sills, and most have glacially eroded and overdeepened basins that contain sediments deposited following the retreat of the glaciers that carved the valleys out. These sedimentary basins preserve a record of post-glacial environments that can be used to evaluate changes in regional sea level, climate, vegetation and other conditions. For example, in cases where the entrance sills were higher than the last glacial maximum sea level, the present-day fjords would have previously been isolated glacial lakes prior to marine ingression due to post-glacial sea level rise; this lacustrine-marine transition is recorded in the fjord sediments, e.g., as flooded deltas and beaches.Over the last 10 years, we have collected high-resolution boomer-sourced seismic reflection data in most of the fjords of Fiordland using a 75-m-long 24-channel Geometrics MicroEel array recording signals from an acoustic boomer source (initially a Ferranti system and then, more recently, one from Applied Acoustics). Processing has been undertaken using commercial (GLOBE Claritas) seismic processing software. We present a summary of this work, showing profiles along a number of the fjords including, from north to south, Milford, Nancy, George, Thompson/Bradshaw, Doubtful, Dagg, Dusky and Long sounds. Seismic sections show a wide variety of sediment accumulations in the fjords depending on periglacial conditions, sill depth, catchment size, catchment rock types and vegetation history, etc. Sediment thicknesses are observed to exceed several hundred metres in some of the basins – which supports an interpretation of interbedded strata of muds, silts, and fine sands. The depositional history of the sedimentary units imaged by these data, in conjunction with additional seafloor mapping, direct seafloor sampling and shallow cores, will be confirmed by deep drilling efforts in the fjords.
Sedimentation and carbon accumulation rates in UK saltmarshes
Authors: Garrett Ed , Smeaton Craig , Gehrels W. Roland , Barlow Natasha , Blake Will , Koot Martha B. , Miller Lucy , Havelock Glenn , McMahon Lucy , Ladd Cai , Austin William
Published: February 2023

Saltmarshes play a key role in sequestering and storing carbon, as well as providing a wide range of other ecosystem services. Assessments of both total carbon stocks and rates of carbon accumulation are vital for quantifying saltmarsh contributions to climate-change mitigation and for guiding efforts to protect and restore coastal wetlands. Current assessments of the rates at which UK saltmarshes accumulate carbon are based on a small and spatially limited dataset. To address this knowledge gap, we estimate sedimentation rates and assess organic carbon density from 22 saltmarshes distributed around the UK. Bayesian modelling quantifies the relationship between depth and age from 210Pb and 137Cs activity data. We combine these sedimentation rates with centimetre-resolution organic carbon density measurements to quantify carbon accumulation rates through time. By upscaling these estimates to the total UK saltmarsh area and fully quantifying uncertainties, we conclude that UK saltmarsh carbon burial rates are lower than previously thought.
Machine learning based two-step urban tree carbon storage estimation fusing airborne LiDAR, and Sentinel-2
Authors: Lee Yeonsu , Son Bokyung , Im Jungho
Published: February 2023

Urban trees are important carbon sink in human settlements by absorbing carbon dioxide and storing them as biomass. As urban areas continue to expand, quantification of carbon storage (CS) in human settlements is becoming important. Usually, urban tree CS is extrapolated using total tree area statistics and carbon stocks per unit area. However, since urban trees show large variability due to diverse growing conditions, additional information such as vegetation vitality or three-dimensional structures should be considered in CS estimation. This study suggests a new two-step approach to estimate urban tree CS using forest tree carbon stocks and then correcting it to human settlements via machine learning (ML) regression models and remote sensing data. First, urban tree CS was estimated using a high-resolution urban tree canopy cover map which classified by deep-learning approach and forest tree carbon stocks which were calculated using merchantable growing stocks and biomass expansion factor (Step 1 CS). Second, urban tree CS was estimated via ML models using Step 1 CS, Sentinel-2 images, and airborne light detection and ranging (LiDAR) measurement as independent variables. As dependent variable, the field-measured CS values calculated using allometric equations and field-measured diameter at breast height using terrestrial LiDAR were utilized. Step 2 CS using random forest showed the best performance with a correlation coefficient of 0.90 and a root-mean-squared-error of 0.48. Tree height and normalized difference vegetation index appeared as important variables in estimating urban tree CS. Suggested model can estimate urban tree CS more sophisticatedly and spatially explicitly. The output, high-resolution urban tree CS map, can be used in urban planning to achieve carbon neutrality and pleasant urban environment. 
Comparing different radar-raingauge precipitation merging methods for Tuscany region
Authors: Ciampalini Rossano , Antonini Andrea , Mazza Alessandro , Melani Samantha , Ortolani Alberto , Rosi Ascanio , Segoni Samuele , Moretti Sandro
Published: February 2023

Radar-based rainfall estimation represents an effective tool for hydrological modelling. Nevertheless, this data type is subject to systemic and natural perturbations that need to be considered before to use it. Because of that and to improve data quality, corrections based on raingauge observations are frequently adopted. Here, we compared the efficacy of different radar-raingauge merging procedures over a regional raingauge-radar network focusing on a selected number of rainfalls events.We adopted the methods: 1) Kriging with External Drift (KED) interpolation (Wackernagel 1998), 2) Probability-Matching-Method (PMM, Rosenfeld et al., 1994), and 3) a kriging mixed method exploiting the Conditional Merging (CM) process (Sinclair-Pegram, 2005) based on elaborations available at DPCN (Italian National Civil Protection Department). These methods have been applied on the Tuscany Regional Territory using raingauge recorded rainfalls at 15’ time-step and CAPPI (Constant altitude plan position indicator) reflectivity data at 2000/3000/5000 m at 5’ and 10’.Relationships describing precipitation VS radar reflectivity were integrated and elaborated as part of the development of the merging procedures, while the comparison involved the analysis of variance and diversity coefficients. Kriging-based elaborations showed different spatial patterns depending on the applied procedure, with patterns closer to radar variability when using DPCN, and more reflecting the gauge data structure when adopting KED. The probabilistic method (PMM), instead, had the advantage of integrating the gauge data while preserving the spatial radar patterns, confirming interesting perspectives.
Tracing the water footprint of food losses the in trade network: the case of wheat
Authors: Semeria Francesco , Laio Francesco , Ridolfi Luca , Tuninetti Marta
Published: February 2023

Food loss and waste is increasingly becoming a topic of great public concern: in 2011, FAO presented the estimate that around one third of the world’s food was lost or wasted every year and SDG 12 (“Sustainable consumption and production”) from Agenda 2030 includes among its targets to “halve per capita global food waste” and to “reduce food losses”. The impact on environmental resources is significant: in particular, 24% of total freshwater resources used in food crop production are lost in the different stages of food loss and waste. While in high-income countries food is mainly wasted at the consumer level, low-income ones record losses concentrated in the agricultural and post-harvest stages. Globally, food markets are telecoupled and globalized, so wasted food has effects on water resources in the whole supply chain, propagating along the trade network up to the countries of initial production, where water resources have been utilized, often through irrigation, altering the local hydrological cycle. The reconstruction of such network is one of the most challenging aspects of tracing the impact of food waste on water resources. The difficulties are due to the numerous food re-exports and nested supply chains, to the different origins of food waste (from production to distribution and consumption), and to the marked variability of the country-specific unit water footprints. As a key hypothesis, we assumed that in each country the ratio between imports and domestic production would be the same in both domestic consumption and exports, to cope with re-export feedbacks in the network. Focusing on the emblematic case of wheat and its derivatives (e.g., flour, bread, pasta), we were able to reconstruct the complex global network that connects losses and wastes at any stage along the supply chain with the corresponding wasted water resources.Our results show that, for most countries, the network is very extensive and involves many states around the world. For example, in 2016 over 20 foreign countries employed their water resources to produce wheat which in turn was wasted as bread in Italy at the consumer level, accounting for around 15% of the bread’s water footprint (870 m3/t).  This highlights how much water resources are now globalized and that the waste of food in a country can impact even very distant water resources. We also quantify the contribution of each waste component, from agriculture’s field losses to consumers’ household wastes. For Italy, 54% of losses related to bread are at the consumption stage, while only 6% occur at the agricultural stage. Eventually, we present how the relative importance of each component varies, depending on the network of countries involved in the production, storing, processing, distribution and consumption of food.