bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing water status of two urban tree species : Acer Platanoides and Tilia Euchlora by very high spatial resolution imagery and field micro-dendrometers measurements
Authors: Canovas Lola , Martiny Nadège , Bur Thomas , Marilleau Nicolas , Hartmann Christian
Published: March 2024

Urban areas are faced with issues of particulate air pollution and urban heat islands, in a context of a growing number of their inhabitants. Ecosystem services provided by urban trees are impacted by the health and functioning mechanism of the trees, in particular the evapotranspiration process. The impact of urban specificities on tree functioning has yet to be fully studied. In recent years, improvement in remote sensing and the availability of very high spatial resolution imagery offer new perspectives and working methods for urban tree. The aim of this study is to explore how Pleiades imagery and field micro-dendrometer measurements can assess the health and water status of the two main tree species present in the city of Dijon: Acer Platanoides and Tilia Euchlora. The work has been leaded in 3 steps. First, the very high spatial resolution Pleiades imagery has been used to identify tree canopy in Dijon city. Generalist and empirical approaches are compared, for instance NDVI, MSAVI2 and EVI vegetation indices. Then, tree canopy, tree species (based on field records), morphological parameters (from topographic data and digital elevation model) and proximity to pollutant emissions are used to select six sites in Dijon. In each site, one or two mature trees (six Tilia Euchlora and five Acer Platanoides overall) are finally equipped with the micro-dendrometer (PepiPIAF system) to record daily stem diameter variations. Variables reflecting the water status of the trees, like the maximum daily shrinkage, are then calculated from these field measurements. The first results are encouraging, a marked response of vegetation indicators to precipitation is observed, with high values after heavy rainy episodes. The next step is to establish the link between vegetation indices obtain via remote sensing and micro-dendrometers measurements. This could in turn be a step forward the modelling of trees’ water status at a high spatial resolution at the scale of the city. 
Microscale investigations of the evolution of deformation mechanisms in a low-temperature marble mylonite, NE Attica, Greece
Authors: Bakowsky Christina , Dubosq Renelle , Schneider David , Grasemann Bernhard
Published: March 2024

Carbonate rocks compose 15% of Earth’s ice-free continental surface and commonly consist of kilometer thick sequences that host complex crustal-scale fault zones, accommodating displacements on the order of tens of kilometers. These intricate fault networks significantly influence fluid migration, further controlling crustal mechanics. Understanding the deformation mechanisms of calcite and dolomite, two of the dominant carbonate forming minerals, is therefore essential for predicting the rheological properties of carbonate rocks. Herein, we conduct a microstructural analysis to investigate the interactions between brittle-ductile structures under greenschist facies conditions in a naturally occurring biphasic marble mylonite. The framework of the mylonite, which is exposed in a tectonic window north of the Greek Cyclades on the Attica peninsula, indicates deformation occurred at 300-350°C and 7-8 kbar during the late Oligocene. The mylonitization is overprinted by a weak, but pervasive axial plane cleavage. A second strong, and densely spaced axial plane cleavage, oriented perpendicular to and truncating the first set, creates a ‘pseudo-boudinage’ of the dolomite layers. Localized shear bands cross-cutt the second axial plane cleavage set, suggesting a fourth phase of deformation. Electron backscatter diffraction analysis of the mylonite reveals coarse (30-200 µm) calcite with evidence of crystal-plasticity in the form of low-angle (
Long-time behaviour of stochastic geophysical fluid dynamics models.
Authors: Carigi Giulia
Published: March 2024

The introduction of random perturbations by noise in partial differential equations has proven extremely useful to understand more about long-time behaviour in complex systems like atmosphere and ocean dynamics or global temperature. Considering additional transport by noise in fluid models has been shown to induce convergence to stationary solutions with enhanced dissipation, under specific conditions. On the other hand the presence of simple additive forcing by noise helps to find a stationary distribution (invariant measure) for the system and understand how this distribution changes with respect to changes in model parameters (response theory). I will discuss these approaches with a multi-layer quasi-geostrophic model as example.
Modelling the Ocean Circulation during the mid-Cretaceous using an Energetically Consistent Internal Wave Model in the Community Earth System Model
Authors: Kattamuri Siva , Paul André , Pollmann Friederike , Green Mattias , Schulz Michael
Published: March 2024

Deep-time climate simulations typically disregard tidal dynamics while trying to reconstruct the paleoclimate. Tidally induced mixing is a dominant part of vertical mixing in the deep ocean, which is key for maintaining ocean stratification and influences the strength of the Meridional Ocean Circulation (MOC). We add this missing tidal mixing component to the Community Earth System Model (CESM) and try to reconstruct the mid-Cretaceous (~90Ma) climate, which is known for its warm, equable climate and low meridional temperature gradient. In the next step, as an improvement over the default tidal mixing scheme, an energetically consistent internal wave model IDEMIX is used in CESM to get the vertical diffusivity coefficients in simulating the mid-Cretaceous climate. Initially, 90Ma simulations were performed in the conventional method with enhanced constant background diffusivity coefficients for the default vertical mixing scheme and then with the tidal mixing component enabled. Preliminary results from the simulations with tidal mixing show that there is a considerable reduction in the global ocean mean temperature and a change in the strength of MOC in the deep ocean when compared to the simulations without the tidal mixing component. We will be also presenting results from additional experiments that are being performed with the internal wave model IDEMIX as the tidal mixing parameterization in the model. IDEMIX is forced by the dissipated barotropic tidal energy, which is modelled from the mid-Cretaceous bathymetry. With the IDEMIX parameterization, we expect more realistic results for ocean circulation hoping to reduce the disagreements between proxy data and model simulations.
Geophysical characterisation of an actively gas-seeping pockmark on the West-Svalbard continental slope
Authors: Viola Irene , Bünz Stefan , Giuliana Panieri , Massimiliano Zattin
Published: March 2024

Seabed fluid flow is a globally significant natural process with implications for various aspects of the marine and global environment.The study focuses on methane seeping from a newly investigated pockmark in one of the most significant seepage province in the world: the West Svalbard continental drift. The study was conducted on historical databases compared with new geophysical data acquired during Akma2 Ocean Senses expedition in may 2022. The expedition employed ROV technology, SBP data, heat flow and bathymetric data to uncover unprecedented insights into the geological and environmental factors at play. In particular, the study conducted on this active gas-seeping pockmark provided insight about its formation, migration, geothermal and gas exchanges and impact on the marine environment. The importance of understanding the mechanisms and identifying seabed fluid flow is emphasised for comprehending its distribution over time and space. The features associated with fluid flow are determined by fluid and migration mechanisms, influenced by the stress environment within sediments.This study adds new information that can be used for understanding the impact of seabed fluid flow for addressing environmental hazards, evaluating energy resources, and climate changes.
Impacts of using thermal stratification dependent critical bulk Richardson number in a PBL scheme of a climate model
Authors: Namdev Prabhakar , Sharan Maithili , Mishra Saroj K.
Published: March 2024

The planetary boundary layer height (PBLH) is a crucial component in almost all planetary boundary layer (PBL) parameterizations, and the PBLH is calculated using a method based on the bulk Richardson number (RiB), which utilizes a threshold value of RiB called the critical bulk Richardson number (Ricr). In most of the PBL schemes, Ricr prescribed as one single value, and its dependency on thermal stratification has been ignored. In the present study, an effort has been made to incorporate Ricr based on different stratification conditions following a study by Zhang et al. (2014) in the PBL parameterization proposed by Holtslag and Boville (1993) of the National Centre for Atmospheric Research Community Atmosphere Mode version 5 (NCAR-CAM5). The modified scheme is evaluated over Indian land and associated different climatic zones in simulating PBLH, surface turbulent fluxes, near-surface atmospheric variables, and precipitation during the winter (DJF), pre-monsoon (MAM), monsoon (JJA), and post-monsoon (SON) seasons. The simulations with the default and modified schemes have been carried out at a spatial resolution of ~1o for a period of six years, discarding the first year as spin-up time and considering the last five-year simulation for the analysis. The study reveals that the modified scheme is able to produce more accurate estimates for PBLH than the default scheme compared to the ERA5 reanalysis dataset over Indian land, which further enhances the accuracy of turbulent transport of heat, moisture, and momentum inside the PBL under various atmospheric stability regimes. The modified scheme noticeably improved the simulation of surface sensible and latent heat fluxes, surface air temperature, and precipitation compared to the default scheme over Indian land during all four seasons.
Evidence of ongoing SF6 emissions in Germany
Authors: Meixner Katharina , Engel Andreas , Schuck Tanja J. , Wagenhäuser Thomas , Couret Cedric , Meinhardt Frank , Stanley Kieran M. , Manning Alistair J. , Jordan Armin , Gutièrrez Xochilt , Kneuer Tobias , Kubistin Dagmar , Lindauer Matthias , Mueller-Williams Jennifer
Published: March 2024

Sulfur hexafluoride (SF6) is a greenhouse gas with an estimated atmospheric lifetime of about 850-1280 years and a global warming potential of 24,700 over 100 years. As this strong greenhouse gas continues to be used in switchgear, circuit breakers, transformers and in other applications; monitoring emissions worldwide is essential. Some global and regional measurement networks, including the AGAGE, NOAA and ICOS programmes, have been measuring surface-based SF6 for several years. Through these measurements and inverse modelling, it has been shown that there are still significant SF6 emissions in western Europe, the largest source estimated to be in southern Germany.Here we present the first time series of all available SF6 observations in Germany to localise the most important source regions of SF6. Data from the following stations were used: Taunus Observatory (AGAGE), Zugspitze / Schneefernerhaus (UBA Germany, GAW, ICOS), Karlsruhe (DWD, ICOS), Hohenpeissenberg (DWD, GAW, ICOS), Lindenberg (DWD, ICOS), Ochsenkopf (MPI-BGC, ICOS), Steinkimmen (ICOS), Gartow (ICOS) and Schauinsland (UBA Germany, GAW, ICOS). This distribution of observation sites provides good resolution of SF6 emissions in Germany. Despite the annual National Inventory Reports to the UNFCCC suggesting a decline in SF6 emissions in Germany, observations show continued episodes of elevated mixing ratios. This is indicative of continuing local emissions in Germany. Depending on wind direction, the highest levels of SF6 were measured at Zugspitze, Schauinsland, Karlsruhe and the Taunus Observatory, consistent with a source in southern to south-western Germany.  The Karlsruhe station stands out in particular, with maximum mixing ratios of more than 70 ppt. In addition to an analysis of such pollution events, the observations are also used in the top-down inverse model InTEM (Inversion Technique for Emission Modelling) coupled to the atmospheric transport model NAME (Numerical Atmospheric Dispersion Modelling Environment).
Agroforestry management practices as nature-based solutions for climate change adaptation in the Galapagos Islands
Authors: Alomia Ilia , Montes Yessenia , Paque Rose , Dixon Jean , Molina Armando , Vanacker Veerle
Published: March 2024

Small tropical islands in the Pacific Ocean are highly vulnerable to climate change. Nature-based solutions can help local communities adapt their local agricultural systems. Through a comparative analysis, we evaluated the effects of agroforestry management practices on soil temperature, soil water availability and storage, and carbon stocks in Santa Cruz Island (Galapagos Archipelago). We installed six monitoring sites that consist of two replicates per agroforestry management practices: (i) conservation of native forest, (ii) traditional agroforestry, and (iii) abandoned farmland in passive restoration. After pedological characterization of the sites, the soil physicochemical and hydrological properties were determined in the laboratory. Over 30 months (July 2019 to December 2021), the environmental sensors captured the hydrometeorological and soil physical and hydrological properties of the sites. This was done by a dense network of rain gauges, air temperature and relative humidity sensors, and time-domain reflectance probes that registered volumetric water content and soil temperature.We measured differences in soil temperature, moisture availability and soil organic carbon content between soils under forest, traditional agroforestry and passive restoration. Forest soils are protected from direct solar radiation, and trees keep the soil 12% cooler than soils converted to agricultural land. Soil moisture is 20% higher under forest than under traditional agroforestry or abandoned farmland, and forest soils have a lower dry bulk density, lower saturated hydraulic conductivity and higher water retention capacity. The forests and sites under passive restoration store more than 377 Mg C. ha-1 (1 m depth), about 50% more than under traditional agroforestry. The study shows that conserving forest patches in an agricultural landscape might be a promising strategy to mitigate increasing soil temperatures, agricultural drought, and decline in soil organic carbon content. However, more studies on landscape scale are needed to corroborate those results.
Characterisation and locations of volcanic high frequency tremor above 10 Hz on Mount Etna
Authors: Weber Maurice , Bean Christopher , Smith Patrick , Lokmer Ivan , Zuccarello Luciano , De Angelis Silvio , Soubestre Jean , Minio Vittorio
Published: March 2024

When it comes to volcanic tremor, low frequency signals (below 5 Hz) are well investigated. Such tremor signals can usually be linked to magma movement or gas fluctuations. However, little is known about seismic tremor signals on Mount Etna above 10 Hz. Hence, a large field campaign targeting high frequencies was undertaken in the summer of 2022. It consisted of the deployment of six dense circular arrays ranging from 30 to 200 m apertures of seismic nodes installed around the summit craters. It led to the detection of tremor bands between 10 and around 20 Hz as well as the typical tremor signals below 5 Hz.The tremor is detected with good coherency at stations within one array (despite an extreme level of scattering) in good agreement with the energy distribution in the average amplitude spectra of the array. The high frequency tremor varies strongly in intensity over time periods of one hour and re-occurs several times throughout the deployment period of almost a week. In contrast the tremor below 5 Hz is relatively constant. This suggests that the high frequency tremor could be a separate signal due to a process that may not yet be fully understood.Localisations of these tremor episodes point to or near the Bocca Nuova Summit Crater which was actively degassing at the time. Interestingly, high frequency seismic tremor is matched in time very well by a narrow 3.5-5 Hz acoustic band. While the match in time clearly suggests a connection between the two signals, the different frequencies indicate two different but linked processes happening simultaneously. The acoustic signal implies degassing processes. Later during the deployment tremor episodes are found which are accompanied by much weaker acoustic signals (if at all present) suggesting gases might not necessarily be involved in generating the detected seismic tremor at all.In summer 2023 we undertook a complementary second deployment of seismic, acoustic and optical camera data in the Bocca Nuova summit area. Once again, we find tremor below 5 Hz, however high frequency characteristics are different to the previous year with tremor bands less dominant than before and much more constant over time. More than one acoustic band is found as well, also constant over time. In this second data set we use camera recordings of the crater activity as a proxy for degassing activity to try and understand the precise origin of these seismic and acoustic volcanic signals.
The relative prevalence of wave-packets and coherent structures in the inertial and kinetic ranges of turbulence as seen by Solar Orbiter
Authors: Bendt Alina , Chapman Sandra , Dudok de Wit Thierry
Published: March 2024

The Solar Orbiter (SO) mission provides a unique opportunity to study the evolution of turbulence in the solar wind across different distances from the sun and different plasma conditions. We use SO observations of extended intervals of homogeneous solar wind turbulence to investigate under what conditions the turbulent cascade in the solar wind is supported by either, or both of two distinct phenomenologies, (i) wave- wave interactions and (ii) coherent structure formation and interaction.We identify nine Solar Orbiter observations of extended intervals of homogeneous solar wind turbulence where each interval is over 10 hours long without current-sheet crossings and other large events. We perform a systematic scale-by-scale decomposition of the observed magnetic field using two wavelets that are known to discriminate between wave-packets and discontinuities, the Daubechies 10 (Db10) and Haar respectively.A characteristic of turbulence is that the probability distributions (pdfs) of fluctuations obtained on small scales exhibit extended supra-Gaussian tails, and as the scale is increased, the moments decrease and there is ultimately a cross-over to Gaussian pdfs at the outer scale of the turbulence. Using quantile quantile plots, we directly compare the fluctuations pdfs obtained from Haar and Db10 decompositions. This reveals three distinct regimes of behaviour. On larger scales, deep within the inertial range (IR), both the Haar and Db10 decompositions give essentially the same fluctuation pdfs. On the smallest scales, deep within the kinetic range (KR), the pdfs are distinct in that the Haar wavelet fluctuations have a much broader distribution, and the largest fluctuations are associated with coherent structures. On intermediate scales, that span the IR-KR scale break identified from the power spectra, the pdf is composed of two populations, a core with a common pdf functional form for the Haar and Db10 fluctuations, and extended tails where the Haar fluctuations dominate. This establishes a cross-over between wave-packet dominated phenomenology in the IR, to coherent structure dominated phenomenology in the KR. We find that the intermediate range of scales is quite narrow around 0.9 au so that the crossover from wave-packet to coherent structure dominated phenomenology is quite abrupt. At around 0.3au, the crossover occurs over a broader range of scales extending down to the 0.25s scale and up to 4s.As coherent structures and wave-wave interactions have been proposed as candidates to mediate the turbulent cascade, these results offer new insights into the evolution of the turbulent cascade with distance from the sun.
Combined approach for hillslope hydrogeological assessment in rainfall-induced shallow landslides prone area.
Authors: Vivaldi Valerio , Bordoni Massimiliano , Torrese Patrizio , Meisina Claudia
Published: March 2024

In the last years extreme rainfall events and seasonal cumulated rainfall distribution variations occurred, increasing also the arise of slope instabilities, mostly in the more susceptible areas.Heavy rainfall events are one of the main triggering factors in shallow landslides occurrence: therefore, a better understanding of the trigger processes is necessary, also for early warning systems development and improvement. The soil water content of the first 3-5 meters of soil becomes thus an important shallow landslide predisposing factor to monitor. At this purpose, the mainly employed technique for soil moisture monitoring is the in-situ measurement, through different types of soil probes directly installed in the first soil layers. However, despite being a very precise technique, this monitoring technique provides only for a punctual dataset.An integrated method to extend the hydrological characterization from site-specific to a slope scale is presented, combining geotechnical analyses, field data monitoring and geophysical investigations, in particular the electrical resistivity tomography (ERT).Geophysical models of the first subsoil were carried out through different geoelectrical investigations (2D-3D-4D) and were calibrated and interpreted based on soil monitoring data, stratigraphic logs and trenches carried out in the study areas.Estimation of the test sites average bulk permeability was performed through time-lapse 3D-S surveys, carried out by simulating very intense precipitations through manual irrigation, that allowed to determine the resistivity variation from undisturbed to disturbed conditions.Finally, resistivity variations were correlated to soil horizons geotechnical parameters to perform hydrogeological conceptual models of the first soil horizons.This conference abstract is part of the project NODES which has received funding from the MUR – M4C2 1.5 of PNRR funded by the European Union - NextGenerationEU (Grant agreement no. ECS00000036).
Pasture N2O emission fluxes by eddy covariance - partitioning and driver analysis
Authors: Ammann Christof , Barczyk Lena
Published: March 2024

Grazed and fertilized pastures are considerable sources of the greenhouse gas N2O. While fertilizer applications usually lead to short emission pulses, animal excreta lead to small-scaled emission hotspots resulting in a non-homogeneous source distribution. The strong spatial and temporal source variability represents an inherent problem for the quantification of gaseous emissions from pastures with chamber techniques. The eddy covariance method, integrating emissions over a larger footprint domain, is well suited to quantify total field-scale N2O emissions, but the partitioning of emissions for different sources and the determination of source-specific emission factors (according to the IPCC guidelines) is still a challenge.We present results of two multiple-year field experiments carried out in different regions of Switzerland. The investigated pastures were grazed by dairy cows in an intensive rotational management. The fields were additionally fertilized with organic and/or mineral fertilizer. The field-scale N2O fluxes were quantified with the eddy covariance technique using a fast response Quantum cascade laser spectrometer for N2O concentration measurements. The management and environmental conditions resulted in high temporal and spatial dynamics of the N2O fluxes with highest values typically occurring after fertilization events in the summer months. Total annual N2O emissions amounted to between 2.5 and 5 kg N ha-1 y-1. Data-based partitioning methods of different complexity were used to attribute the observed field-scale emissions to the main source classes (grazing excreta, fertilizer application, and background) and to derive annual N2O emission factors. Using random forest and other regression methods the effect of environmental parameters on grazing-related emissions were analyzed.
Gravity inversion of sub-ice shelf bathymetry in West Antarctica using a geostatistical Markov Chain Monte Carlo approach
Authors: Field Michael , MacKie Emma , Wang Lijing , Muto Atsuhiro
Published: March 2024

Sub-ice-shelf bathymetry controls the delivery of warm water to the ice-shelf bottom in West Antarctica, making the bathymetry beneath ice shelves in the Amundsen Sea critical inputs to ice-sheet and ocean models. Previous estimates of the bathymetry have often used deterministic inversion frameworks or do not account for the non-uniqueness of the inverse problem, and ultimately lack robust uncertainty quantification. To provide more robust and reproducible bathymetry models, we implement a random walk Metropolis-Hastings Markov Chain Monte Carlo (MCMC) inversion approach, which iteratively generates model perturbations using random Gaussian fields and forward models the gravity disturbance of proposed bathymetry models. After convergence, our approach samples the posterior distribution allowing for estimation of the mean and variance of the bathymetry while providing realistic models of the sub-ice-shelf bathymetry. An ensemble of bathymetry models can then be used in ice-sheet and ocean simulations to propagate the uncertainty in bathymetry to dynamic ice processes, resulting in better uncertainty quantification of future sea-level rise. In addition to providing more robust bathymetry models, this work provides a step forward in the reproducibility of geophysical inversions by leveraging the growing open-access geoscientific computing ecosystem of Python.
Assessment of saturated hydraulic conductivity-depth relationships and extended soil column thickness in catchment hydrological modelling
Authors: Mendoza Raul , Weerts Albrecht , van Verseveld Willem
Published: March 2024

Reliable quantification of subsurface dynamics in catchment hydrological models largely depends on good estimates of soil hydraulic properties which influence subsurface runoff generation, flows and storage. In most hydrological modelling concepts, the saturated hydraulic conductivity (Ksat) is a key parameter that controls the vertical transfer of water through the soil layers and the lateral subsurface flow. Ksat values are derived from direct measurements, literature, or available soil datasets, most of which do not reach depths beyond 2 or 3 m. This is one of the common motivations for limiting the soil column to shallow depths in most catchment models. This study investigates the model schematization of Ksat in an extended soil column, where Ksat measurements are absent, and the ensuing impacts on catchment hydrological functioning. The motivation is to determine a suitable modelling approach for catchments with deeper soil columns to sufficiently capture the subsurface, including the groundwater, and the feedback with the surface.Different Ksat–depth relationships were conceptualized and implemented in the distributed hydrological model wflow_sbm. Most wflow_sbm applications so far have used a standard soil column thickness of 2.0 m and an exponentially declining Ksat with depth. The different Ksat schematizations were tested in the Dutch-German catchment Vecht where the model soil column was extended to capture the groundwater system.The results reveal the impact of an extended soil column and the different Ksat schematizations on catchment water balance, surface and subsurface flows, and water table depths. Varying changes were observed among the different Ksat schematizations but all produced generally good, and in some cases improved, model performance when compared with observations of river discharge and water table depth. The results demonstrate the suitability of extending the soil column and applying the different vertical Ksat–depth relationships in catchment hydrological models.
Adjoint-Source Inversion of Microseismic Sources with DAS in Boreholes
Authors: Tuinstra Katinka , Lanza Federica , Noe Sebastian , Fichtner Andreas , Rinaldi Antonio Pio , Edme Pascal , Rosskopf Martina , Obermann Anne , Hertrich Marian , Maurer Hansruedi , Giardini Domenico , Wiemer Stefan ,   Bedretto Team
Published: March 2024

Microseismic source processes can be closely monitored during hydraulic stimulations with optical fiber deployed behind borehole casing, using Distributed Acoustic Sensing (DAS). The Bedretto Underground Laboratory for the Geosciences and Geoenergies (BULGG) provides a test site at the scale of hundreds of meters (meso-scale), where multiple boreholes are instrumented with fibers around a stimulation well. This enables the characterization of source properties of induced seismicity thanks to the dense sampling of the wavefield close to the stimulated region.In 2023 various stimulation activities in the BedrettoLab produced M100 Hz). This study provides a step forward to monitoring microseismicity in hydraulic stimulations with fiber-optic measurements.
Radiative effects of UTLS aerosols in climate simulations
Authors: Tost Holger , Vella Ryan , Hoor Peter
Published: March 2024

The UTLS (upper troposphere lower stratosphere) is known for its strong susceptibility of changes of the radiative impact of their constituents, with effects relevant also for near surface temperatures. To assess the effects of particulate radiative effects, we have developed a new calculation scheme for the optical properties of internally and externally mixed aerosol compounds both in the shortwave (visible and near-infrared) and the longwave spectrum, differentiating between scattering and absorbing contributions. The scheme is easily extendable to consider specific compounds, e.g., including volcanic ash or differentiating between organics from anthropogenic sources versus biogenic SOA.This scheme has been implemented into the chemistry climate model EMAC to investigate the effects of aerosol radiative impacts in the UTLS on the troposphere. This study shows corresponding results, including an assessment of how the refractive indices of the individual compounds have an overall impact on the global radiative effects.
Investigating Seagrass as a Nature-Based Solution for Coastal Protection: toward a Digital Twin Modelling Framework
Authors: Alessandri Jacopo , Federico Ivan , Biocca Nicolás , Causio Salvatore , Bonamano Simone , Piermattei Viviana , Mentaschi Lorenzo , Coppini Giovanni , Marcelli Marco , Valentini Andrea , Pinardi Nadia
Published: March 2024

The large presence of human infrastructure, protected natural environments, cultural heritage and major economic activities makes the coast one of the most vulnerable areas to climate change-related problems such as sea level rise and an increasing number of extreme events. Storm surges are the main cause of flooding and coastal erosion due to the combined effects of waves and currents that resuspend and transport sediments. In addition to the classic "gray" solutions, including engineered structures such as seawalls and groins, nature-based solutions have emerged in the last decade, based on the idea of finding solutions that are both effective and environmentally sustainable. It is well known that seagrass meadows can provide critical ecosystem services. Among them, coastal protection is one of the most important. The aim of this work is to investigate the effects of seagrass meadows on physical ocean variables relevant for sediment transport and sea level using a digital twin of the ocean. The seagrass is implemented in a three-dimensional unstructured grid ocean model (SHYFEM-MPI) as a form drag in the momentum equations, considering the flexibility of the plants. The implementation was verified with idealized test cases and three focus areas were selected along the Italian coast. The three areas are the Venice lagoon, the Emilia-Romagna coast (northern Adriatic Sea) and the Civitavecchia coast (Tyrrhenian Sea) and differ in morphology and seagrass species (Zostera marina, Posidonia oceanica). These areas are representative of a wide range of coastal environments. Interestingly, the results show different behavior depending on the geomorphology of the area. The lagoon environment, when exposed to extreme storm surge events, shows an alternating pattern of sea level variation with a reduction that can reach 5-10%, while in the other focus area the effect of seagrass on sea level is negligible. In all three areas, seagrass is very effective in reducing bottom current velocity by up to 50-60%, suggesting a possible important role against coastal erosion.
Linking geology and art: observations to interpretations of the Sanetsch Fold, Helvetic Alps
Authors: Sleath Phoebe , Butler Rob , Bond Clare
Published: March 2024

Illustrations of field outcrops are a fundamental tool for scientists in both research and learning as an important method of documenting interpretations. Whether field sketches, photos, concept diagrams or virtual outcrops, researchers through time have used a variety of different ways to visualise outcrops. What do the views and annotations a researcher chooses to represent a field outcrop tell us about the evolution of understanding and uncertainty in geology?Here we investigate a variety of illustrations of a well-studied outcrop in the Helvetic Alps of Switzerland, at the Col de Sanetsch. The Urgonian limestone is folded into a 500m high NW-facing fold pair, exposed in the South face of Spitzhorn (2807m). The fold has a complicated structural history, as it contains an array of SE-dipping normal faults which have been onlapped by Cenozoic turbidites before folding. Views of the outcrop are very accessible, by cable car or road, but the entire outcrop is a cliff and almost completely inaccessible.During field mapping in 2022, watercolour sketches of the outcrop were completed from different viewpoints, along with photos and GPS points. We compare these with historical illustrations of the outcrop by other researchers, from sketches in field notebooks to photographs and figures in published papers. By analysing how the outcrop has been drawn and therefore how the researcher has percieved the geology, we can better understand how they have worked and where they fit in the evolution of ideas. This has implications for our own work, finding the right tools and the best perspective to clearly illustrate our work, understand the science and communicate interpretations.
Predicting GOES Electron Fluxes With Comprehensive Inner Magnetosphere-Ionosphere (CIMI) Model for Different Types of Geomagnetic Storms
Authors: Buzulukova Natalia , Rodriguez Juan , Kress Brian , Fok Mei-Ching , Holappa Lauri , Redmon Rob , Smirnov Artem
Published: March 2024

The Comprehensive Inner Magnetosphere-Ionosphere (CIMI) model has proved to be an effective tool to understand dynamics of charged particles in the Earth's inner magnetosphere. The CIMI model can predict fluxes of radiation belt electrons, ring current particles, cold plasmaspheric population as a function of solar wind parameters, indices, equatorial radial distance, local time, energy and pitch-angle information (for radiation belts/ring current). For electrons, the CIMI model solves advection-diffusion equation combined with statistical models for chorus wave intensity and tabulated diffusion coefficients to predict radiation belt fluxes. An important part of the CIMI model is calculation of the electric field in the inner magnetosphere that is self-consistent with the ring current pressure distribution. For this study, we use the CIMI model to simulate GOES electron fluxes in the energy range 40-450 keV. Fluxes in this energy range are highly dynamic and their prediction is very important for complete space weather analysis. Additional motivation for understanding the dynamics of this energy range is demonstrated by recent findings that establish the population of electrons with energies of 100–200 keV in GEO orbit as a new class of previously neglected space weather hazards. We simulate CIMI electron fluxes for ~20 CIR-type geomagnetic storms and ~20 CME-type geomagnetic storms, and study both the model response and GOES fluxes as a function of the drivers (storm type, IMF Bz , Vx, dynamic pressure) and the local time sector. Finally, we evaluate the model's performance in terms of statistical metrics and propose ways to improve the model's predictions.
ML Surrogate for Tsunami Forecasting and Hazard Assessment in Eastern Sicily
Authors: Ragu Ramalingam Naveen , Briseid Storrøsten Erlend , Gibbons Steven , Johnson Kendra , Davies Gareth , Lorito Stefano , Abbate Alice , Volpe Manuela , Romano Fabrizio  , Løvholt Finn , Pagani Marco , Martina Mario
Published: March 2024

Addressing the challenges associated with the high computational cost of tsunami inundation simulation has been a persistent issue, particularly in capturing earthquake source uncertainty and solving the nonlinear shallow water equations on high-resolution grids. This study aims to alleviate this computational burden by leveraging machine learning surrogates. Further, evaluating these ML models is often hindered by their black-box nature and the limited size of training and testing datasets, posing challenges for practitioners. We propose an encoder-decoder neural network where offshore tsunami waveforms and local co-seismic deformation fields serve as the basis for predicting high-resolution inundation maps at 10m grids. The model is applied to the coastal region of Catania in Sicily, Italy, integrating diverse earthquake scenarios from a large simulation dataset of 53,550 tsunamigenic events in the Mediterranean Sea. We adopt a pretraining-fine-tuning approach for building the machine learning surrogate and address crucial questions regarding the efficient selection of training scenarios, model design, and training. Leveraging this large simulation dataset, we identify specific locations, scenarios and model conditions where the machine-learning surrogate demonstrates sufficient accuracy and reliability. This provides an efficient mechanism for long-term tsunami hazard assessment or urgent tsunami prediction in real-time situations.
Thompson Microphysics Updates in the Unified Forecast System
Authors: Sun Ruiyu , Yang Fanglin , Hong Songyou , Bao Jianwen , Han Jongil , Aligo Eric , Cheng Anning , Thompson Greg , Dong Jili , Liu Qingfu
Published: March 2024

The Thompson microphysics scheme was evaluated in the Unified Forecast System (UFS) for medium-range weather application in both atmosphere-only and fully coupled atmosphere-ocean-ice-wave system configurations. Initial tests based on the Global Forecast System (GFS) version 16 configuration showed that the Thompson microphysics scheme became unstable with a typical GFS time step. An inner-loop time-splitting approach and a new semi-Lagrangian sedimentation algorithm for rain and graupel were implemented in the scheme to alleviate this numerical instability problem. To reduce biases of radiative fluxes  at the surface and at the top of the atmosphere, the conversions from cloud ice to snow and from snow to graupel in the scheme were modified along with the falling velocity of cloud ice. A few other parameters related to the cloud ice formation process were also adjusted to help improve the accuracy of radiative fluxes. Convective cloud condensate was included in the calculations of the total cloud cover and radiative transfer. Both atmosphere-only and air-sea coupled experiments were conducted to examine the impacts of these changes on global and regional forecast skills at different temporal and spatial scales.  
GRACE for Earth system science: novel insights into hydrology, sea level rise, and solid Earth uplift
Authors: Vishwakarma Bramha Dutt
Published: March 2024

The Gravity Recovery and Climate Experiment Satellite mission has provided estimates of spatiotemporal changes in the Earth’s gravity field, which represents mass transport near the surface of the Earth. This unique satellite mission has been used to study groundwater depletion, lake volume changes, sea level rise, and the viscoelastic response of solid Earth to glacial cycles; glacial isostatic adjustment. In this talk, I will share my experiences: published, unpublished, and even incomplete, in using GRACE data for Earth system science and emphasize the power and limitations of this unique satellite mission. 
Northern high latitude peat fires: from lab to modelling 
Authors: Tarasi Dimitra , Boleti Eirini , Blackford Katie , Kasoar Matthew , Grillakis Emmanouil , Rein Guillermo , Mulyasih Hafizha , Voulgarakis Apostolos
Published: March 2024

Climate warming is occurring most rapidly at high latitudes, heightening the vulnerability of carbon-rich peatlands to fire. Northern peatlands comprise the largest terrestrial carbon store, and exert a net cooling effect on the climate. Warmer and drier conditions due to the anticipated climate change are expected to contribute substantially to increased fire severity and frequency in the northern high latitudes, potentially shifting peatlands from being carbon sinks to being greenhouse gas emission sources. Therefore, peat fires, which are considered the largest and most persistent fires on Earth, can significantly impact the global carbon cycle, atmospheric composition, climate, air quality, and human health. Representing peatland fire feedbacks to climate in Earth system models is essential for accurately predicting the future of the climate system. Here, we present the first steps of an effort to distill lab results on peat burning and emissions into global fire modelling. Since peat moisture content and the depth of burn have been experimentally proved to be critical for the representation of peat fires, we aim to incorporate those mechanisms into a global model functionality. More specifically, we aim to represent the mechanistic understanding of the ignition and spread of peat fires in INFERNO-peat, the peat module of the JULES-INFERNO global fire model. To assess the added value of our updated model, we compare the simulated burnt area and carbon emissions with observation-based products. As boreal regions remain a big mystery for the future of our planet, our improved model representation of peat fires in northern high latitudes contributes to a better understanding of future atmospheric composition, radiative forcing and climate. 
Mineral dust in the climate system: Dust source types and their response to environmental changes in a changing climate
Authors: Schepanski Kerstin
Published: March 2024

Mineral dust aerosol particles are tiny soil particles mobilized and entrained into the atmosphere by wind. Suspended in the atmosphere and transported away from source regions by prevailing wind systems, dust aerosol alters the Earth’s radiation budget, stimulates cloud and precipitation formation processes, and modulates the carbon cycle as it may enhance bio-productivity due to its mineralogical composition. In the light of the manifold dust feedbacks with relevance to the climate, knowledge on the atmospheric pathway of dust from source to sink is essential for accurate climate simulations. Thereby, the spatio-temporal variability of dust source activity, and consequent dust production and entrainment into the atmosphere is of particular interest as dust emission marks the beginning of the atmospheric dust cycle. Although crucial for the understanding of the climate system, detailed knowledge on the interannual variability of dust source characteristics (i.e., emissivity and their susceptibility to wind erosion) and activity (i.e., occurrence frequency of dust emission events and emission fluxes) is still somewhat limited. In particular the impact of changing environmental conditions on dust sources and their emission variability is not fully understood yet and requires further research. This is also of importance in order to assess the spatially and temporally changing contribution of dust sources to the local and regional atmospheric dust burden and related dust feedbacks.This presentation will provide an overview of different dust source types, their key characteristics, and their response to environmental changes due to climate change with regard to emission flux and dust source activity. It will include examples from remote sensing approaches and dust modelling in order to examine the interannual variability in a changing climate.
Non-destructive tests for monitoring the degradation of reinforced concrete structures: preliminary results of Icarus project
Authors: Capozzoli Luigi , Vasanelli Emilia , Imperatore Stefania , De Martino Gregory , Nerilli Francesca
Published: March 2024

The monitoring of degraded reinforced concrete structures represents one of the most important topics for scientific research. Considering that the global non-destructive testing (NDT) market is constantly growing, the possibility of adopting new methods and approaches to identify possible causes of deterioration is fundamental for saving time and costs for repairs and maintenance in civil structures and infrastructures. Consequently, smart use of existing methods and/or the development of innovative strategies based on the integration of non-invasive methodologies play a crucial role in the field of engineering. In this context, CNR (IMAA and ISPC) and Unicusano have proposed the Italian Research Project of National Relevance (PRIN) – ICARUS, an innovative project based on the development of a multiscale and multisensory integrated approach for the assessment of deterioration in reinforced concrete structures.The starting point of the research involves evaluating the capability of geophysical methodologies and other NDT methods to highlight deterioration phenomena affecting concrete and/or reinforcements (Capozzoli et al, 2021; Fornasari et al,2023). Data obtained non-invasively are supported and validated by destructive analyses to develop improved laws regarding adhesion, slip, and tensile stiffness.The first phase of the research was conducted on three types of reinforced concrete specimens reinforced with ribbed bars, smooth bars, and strands.  A set of specimens with limited dimensions (200x200x200mm) was created in a previous experimental test (Benenato et al. 2020), and some of them were subjected to an accelerated corrosion process. In this research phase, only six specimens were studied, three intact and three corroded, using ground-penetrating radar (GPR) and ultrasonic tests (UT). Pullout tests and microscopic measurements were carried out to validate the approach's usefulness.The specimens were studied without degradation and at the end of the degradation process. Future research will be conducted through monitoring at intermediate levels of corrosion to identify the capability of NDT tests to assess possible deterioration phenomena in the early stages of rebar corrosion.Despite the uncertainties attributable to the limited size of the samples and the heterogeneities of the concrete, preliminary results show the capability of GPR and ultrasonic tests to identify variations related to the corrosion phenomena occurring in reinforced concrete structures. 