bluuebunny/crossref_metadata_2025 huggingface dataset:
Photo-driven processes for the removal of biotoxins derived from Harmful Microalgal Blooms
Authors: Moreno-Andrés Javier , Lage Sandra , Braga Ana Catarina , Romero-Martínez Leonardo , Acevedo-Merino Asunción , Nebot Enrique , Costa Pedro R
Published: February 2023

Harmful Algal Blooms (HABs) are increasing in frequency and magnitude globally. These episodes are associated with the generation of biotoxins, which pose a potential risk to human and animal health. Biotoxins notably affect aquaculture activities and shellfish production, which has a clear impact on food and human health. Consequently, it is sometimes necessary to close the harvesting areas until the organisms are decontaminated. These natural detoxification mechanisms depend largely on the type of toxin and physiology of the organism, resulting in lengthy processes that can cause severe economic losses to aquaculture activities. As the main goal of this communication, we propose a technological alternative for the degradation of marine biotoxins through the implementation of UV technology as a treatment for agricultural, environmental, and health-related purposes. Therefore, advanced photochemical processes should be evaluated for the efficient degradation of marine biotoxins. The toxin selected was okadaic acid (OA), which is a very stable diarrheal toxin (DSP) and has a great impact on shellfish production areas, e.g. on the Portuguese coast. First, irradiation experiments were performed under UV-A, UV-B, and UV-C irradiation. In general, the concentration remained similar after different UV exposures, indicating that there was no observable photodegradation of OA after 3 h of UV irradiation, detecting a maximum degradation of 19.5% (± 0.95) in the UV-C region, suggesting that OA is clearly resistant to UV photodegradation. Second, the combined UV/H2O2, UV/HSO5−, and UV/S2O82 − processes were tested. Two different UV sources were evaluated: LED and low-pressure lamps (LP), performing OA exposure in distilled water and seawater, with a maximum UV exposure of 3 h. In general, a clear degradation of OA is observed in photochemical processes in distilled water, with a slight decrease in efficiency in the UV/H2O2 process with an LED irradiation source. In the case of UV/S2O82 − and UV/HSO5−, both the LP lamp and LED achieved a total degradation of OA. In the case of the marine matrix, the effect is clearly inhibited for the UV/H2O2 process; however, for UV/ HSO5−, salinity does not seem to affect OA degradation, obtaining practically 100% removal. The study of new UV-LEDs would favor aquaculture activities by increasing sustainability and health safety. Likewise, the results obtained might provide the basis for a possible scale-up of technological processes specifically designed for the minimization of marine biotoxins.
Comparing drought simulation performance from large-scale and locally set up hydrological models for large mountainous rivers in Switzerland
Authors: Chang Annie Y.-Y. , Bogner Konrad , Ramos Maria-Helena , Harrigan Shaun , Domeisen Daniela I.V. , Zappa Massimiliano
Published: February 2023

Historically, Switzerland and the nearby alpine countries have not been associated with major droughts. However, in recent years, the European Alpine space has experienced several unprecedented low-flow conditions and drought events. As many economic sectors in the region depend heavily on sufficient water availability, such as hydropower production, navigation and transportation, agriculture, and tourism, it is important for decision-makers to have early warnings of drought tailored to their needs and geographical conditions.The European Flood Awareness System (EFAS) has been in operation since 2012 providing flood risk overviews for Europe up to 15 days in advance. More recently, it has also run long-range hydrological outlooks for sub-seasonal to seasonal horizons. While EFAS early flood warnings have been extensively evaluated in the past years, less attention has been paid to evaluating the system’s ability to detect upcoming drought conditions. In this study, we turn our focus to this other extreme of the spectrum and on EFAS’ predictability of drought events in large Alpine catchments. Our goal is to investigate how hydrological patterns of skill at a large spatial scale can be combined with local model outputs to more accurately inform decision makers on droughts and their spatio-temporal evolution.For this, we evaluate the performance of EFAS comparatively to that of a local model in terms of the ability to simulate drought conditions. The Precipitation-Runoff-Evapotranspiration HRU (PREVAH) local model was set up for 59 stations in Switzerland. The PREVAH model is a distributed conceptual hydrological model that accounts for processes such as evapotranspiration, interception, snow- and ice-melt, soil moisture storage, groundwater storage, and runoff generation. We analyse 25 overlapping stations between the local model and the EFAS reporting stations (river network points where EFAS outputs are available to users), and compare the drought simulation performances of the two models. We focus on evaluating the duration, deficit, and magnitude of the drought events, as well as metrics including Nash–Sutcliffe model efficiency coefficient (NSE) and Kling-Gupta efficiency (KGE).The outcome of this study will lay a foundation for how a large-scale hydrological model like EFAS can complement a local model like PREVAH to improve the predictability of sub-seasonal drought forecasting and provide more reliable early warnings for better water resources management.
Rift escarpment retreat sustains dynamic landscape for Malagasy flora speciation
Authors: Wang Yanyan , Willett Sean , Liu Yi , Zimmermann Niklaus , Pellissier Loïc
Published: February 2023

A high-relief escarpment characterizes the modern topography of the rifted margin of eastern Madagascar. Although it remained tectonically inactive since the formation from rifting with Seychelles-India in the late Cretaceous, the escarpment landscape has been evolving actively, in that the escarpment retreats laterally due to differential erosion between the escarpment and the high plateau since rifting. The topographically active escarpment of Madagascar corresponds to the island's high endemic species richness, although the island itself is a well-known biodiversity hotspot globally.To investigate the role of tectonic-geomorphic processes in shaping the plant diversity of Madagascar, we constructed a model of elevation change over the entire island. Four geological processes were analyzed for the elevation change: the dynamic uplift from mantle upwelling, the escarpment retreat, the faulting in the Ankay-Alotra Graben, and the sporadic volcanism on the island. We then related the model elevation changes to the phylogenetic patterns and mapped species richness of seed plants. Correlation analysis showed consistence between the observed species richness pattern and the elevation change, in particular, elevation change from the escarpment retreat showed the best correlation with the high species richness.We hypothesized that escarpment retreat leads to vicariant speciation and accumulates the species lineages along the escarpment region over geological time. To demonstrate how the surface processes on an escarpment are linked to speciation, we constructed a landscape evolution model simulating fluvial erosion of an escarpment on the edge of a pre-existing, topographic highland. The model shows that the escarpment retreats laterally, and the drainage basins become longer and broader. However, the basin growth rates are heterogeneous, and the main divide develops sinuosity as individual drainage basins grow at different rates. The differential and transient erosion rates between catchments lead to increased segregation of elevation bands between watersheds, creating isolated highlands detached from the escarpment slope, and providing a highly fragmented habitat in both space and time. The habitat connectivity constantly evolves during the retreat, which we believe, links closely to speciation through the various observed morphological processes.  Retreat of the Madagascar escarpment indirectly influences the orographic precipitation and climatic conditions in that the tropical climatic conditions are sustained, and the tropical habitat expands area during the retreat, both are known favorable conditions of speciation. Overall, we conclude that the escarpment retreat sustains a dynamically evolving landscape, which consequently fosters the flora species hotspot of Madagascar, likely through vicariant speciation.
On the use of seismic geophysical methods to characterize different soil compaction levels
Authors: Carrera Alberto , Pavoni Mirko , Barone Ilaria , Boaga Jacopo , Dal Ferro Nicola , Cassiani Giorgio , Morari Francesco
Published: February 2023

To address the non-invasive way of studying soil structure and its dynamics at different scales, several geophysical techniques can complement traditional characterization methodologies. In this context, the most widespread methods for soil investigations rely on the different electrical properties of earth materials which change with the content and salinity of the incorporated fluids. Although the use of seismic methods in soil science studies is not as common as for geotechnical and reservoir characterization, seismic wave fields contain information about the mechanical properties of the subsurface and may offer insights about soil compaction that other geophysical methods cannot provide.In this work, we evaluate the ability of seismic techniques to assess the differences between small and strong degrees of compaction in soils, relating and validating them with traditional direct measurements. The experiment was conducted at the Experimental Farm “L. Toniolo” of the University of Padova in Legnaro (northeastern Italy), under controlled conditions. The acquisition scheme was designed to resolve small-scale seismic velocity contrasts. Three different levels of induced compaction were investigated with indirect (i.e. geophysics) and direct (i.e. bulk density, texture, volumetric water content) measures.Preliminary results of refraction and surface waves seismic analysis clearly agree with traditional direct measurements. We demonstrate that this approach is not only sensitive to the compaction phenomenon, but it allows to observe both its lateral and in-depth variability. This study opens up interesting future scenarios for geophysics to highlight the different mechanical responses caused both by soil plastic deformation and soil water distribution due to increasing compaction. 
Intransitive Atmosphere Dynamics Leading to Persistent Hot–Dry or Cold–Wet European Summers
Authors: Sperna Weiland Ruud , van der Wiel Karin , Selten Frank , Coumou Dim
Published: February 2023

Persistent hot–dry or cold–wet summer weather can have significant impacts on agriculture, health, and the environment. For northwestern Europe, these weather regimes are typically linked to, respectively, blocked or zonal jet stream states. The fundamental dynamics underlying these circulation states are still poorly understood. Edward Lorenz postulated that summer circulation may be either fully or almost intransitive, implying that part of the phase space (capturing circulation variability) cannot be reached within one specific summer. If true, this would have major implications for the predictability of summer weather and our understanding of the drivers of interannual variability of summer weather. Here, we test the two Lorenz hypotheses (i.e., fully or almost intransitive) for European summer circulation, capitalizing on a newly available very large ensemble (2000 years) of present-day climate data in the fully coupled global climate model EC-Earth. Using self-organizing maps, we quantify the phase space of summer circulation and the trajectories through phase space in unprecedented detail. We show that, based on Markov assumptions, the summer circulation is strongly dependent on its initial state in early summer with the atmospheric memory ranging from 28 days up to ~45 days. The memory is particularly long if the initial state is either a blocked or a zonal flow state. Furthermore, we identify two groups of summers that are characterized by distinctly different trajectories through phase space, and that prefer either a blocked or zonal circulation state, respectively. These results suggest that intransitivity is indeed a fundamental property of the atmosphere and an important driver of interannual variability.
Exposed and hidden geohazards: contribution to the volcanic and seismic risk evaluation
Authors: Italiano Francesco
Published: February 2023

The assessment of the volcanic and seismic hazards is still a huge problem for the entire humankind, since every year hundreds of human lives are lost and damages to the economy and to the cultural heritage for billions of euros are recorded. Any natural or industrial risk assessment takes into account two parameters: the probability that an event may occur “P“ and the damage “D” that the event may induce. The scientific community operates to better assess the P parameter either with a probabilistic (earthquakes) and a more deterministic (volcanoes) approach. For the volcanic risk assessment, the P parameter is currently tackled using multidisciplinary observation systems aimed of reconstructing evolution sceneries of ongoing phenomena. The damage parameter “D” is basically evaluated using economic factors that combine the vulnerability factors with their intrinsic value (e.g. buildings, infrastructures, economic activities, human casualties). The better is the evaluation of P and D parameters, the better will be the risk minimization capacity. The risk minimization has severe consequences on the population safety and on the activities planning (including economic, territorial, social etc.) for those area prone to the natural risks. Therefore, to minimize the risk it is necessary to affect the “damage” parameter besides the continuous enhancement of the monitoring methods. In coincidence of volcanic and seismic crises, however, a range of “hidden” effects occur and, unfortunately, they are not yet considered for the evaluation of the D parameter although they are closely related to the territorial planning of the volcanic and seismic-prone areas. Some examples, such as the contamination of drinkable waters, the anomalous degassing of CO2 and radionuclides during seismic and volcanic crisis of the recent past, highlight the necessity of an accurate territorial planning where exposed and hidden natural processes are both considered to gain the result of a correct and effective territory management.
Evaluation of GEOS-CF V1.0 against Surface Observation in Accra: Fine Particulate Matter Concentration
Authors: Owusu-Tawiah Victoria , Yang Benjamin , Thompson Annor , Mwaniki George , Hughes Allison Felix , Appoh Emmanuel , Westervelt Daniel
Published: February 2023

Air pollution is one of the major environmental issues due to increasing anthropogenic activities and its negative impact on human health. Accurate forecasting is crucial in reducing exposure to poor air quality as well as mitigating against the effects of air pollution. For this reason, the performance of available models need to be evaluated to enhance the development of effective early warning systems. The Goddard Earth Observing System composition forecast (GEOS-CF) system is an operational product from NASA's Global Modeling and Assimilation Office (GMAO).The system provides near-real time forecast of atmospheric composites. This study evaluates the GEOS-CF representation of PM2.5 concentrations over Accra against the BAM-1020 ground station measurements. The performance of the model was described using index of agreement (IOA), coefficient of determination (R2) and fraction of prediction with a factor of 2 (FAC2) while the error was assessed with the normalized mean bias (NMB) and root mean square error (RMSE).The results showed good agreement between the GEOS-CF and surface observation with IOA, R2 and FAC2 recording 0.58, 0.52 and 0.81 respectively. The NMB and RMSE were found to be -0.03 and 15.82 respectively. The model skill improved after the application of the XGBoost regression model with an R2 of 0.65 and RMSE of 6.13. The end goal of this study is to apply a bias-correction factor to the model output for air quality forecasting over Ghana.
Investigating causal effects of anthropogenic factors on global fire modeling
Authors: Pande Nirlipta , Dorigo Wouter
Published: February 2023

Humans significantly control the natural environment and natural processes. Global fire ignitions are a prime example of how human actions change the frequency of occurrence of otherwise rare events like wildfires. However, human controls on fire ignition are insufficiently characterised by global fire models because impacts are often indirect, complex, and collinear. Hence, modelling fire activity while considering the complex relationships amongst the input variables and their effect on global ignitions is crucial to developing fire models reflecting the real world. This presentation leverages causal inference and machine learning frameworks applied to global datasets of fire ignitions from Earth observations and potential drivers to uncover anthropogenic pathways on fire ignition. Potential fire controls include human predictors from Earth observations and statistical data combined with variables traditionally associated with fire activity, like weather, and vegetation abundance and state, derived from earth observations and models.Our research models causal relationships between fire control variables and global ignitions using Directed Acyclic Graphs(DAGs). Here, every edge between variables symbolises a relation between them; the edge weight indicates the strength of the relationship, and the orientation of the edge between the variables signifies the cause-and-effect relationship between the variables. However, defining a fire ignition distribution using DAGs is challenging owing to the large combinatorial sample space and acyclicity constraint. We use Bayesian structure learning to make these approximations and infer the extent of human intervention when combined with climate variables and vegetation properties. Our research demonstrates the need for causal modelling and the inclusion of anthropogenic factors in global fire modelling.
Inter-annual and multi-decadal climate variability in hazard forecasting can exacerbate coastal impacts
Authors: Odériz Itxaso , Losada Iñigo J. , Silva Rodolfo , Mori Nobuhito
Published: February 2023

It has been demonstrated that modes of climate variability influence ocean wave and wind climate variability at inter-annual and multi-decadal scales (Odériz et al., 2021), trigger local impacts modifying coastal erosion patterns (Barnard et al., 2015) and disturbing seasonal coastal risk (Wahl & Plant, 2015). Besides, extreme events and modes of variability that have occurred simultaneously have above-normal struck coastlines around the world (Barnard et al., 2017) and have evidenced that omitting them in hazard forecasting can lead to underestimating coastal impacts. Moreover, in long-term analysis, the internal natural variability that modes of variability cause on wave climate can mask global warming trends in areas with vast natural fluctuations, such as the Southern Ocean (Odériz et al., 2021).The complexity of spatiotemporal scales, in addition to a misconception of teleconnections, have led modes of variability to not integrate into coastal management and underestimate their impact on physical and biological hazards. This study identifies energetic and calm teleconnections induced by the leading polar (Arctic Oscillation-AO and Antarctic Oscillation-AAO) and tropical (El Niño Southern Oscillation-ENSO) modes of variability on the world’s coasts. Teleconnections are comprehensively characterized by (1) sign, (2) duration, (3) amplitude, and (4) spatial patterns. Global spatial-temporal fluctuations are analysed by season, parameter (near-surface wind velocity, total-wave power, swell-wave power, and wind sea-wave power), and planetary systems (winds and wave climates).As an example of the results, we found that wind velocity increases up to ~+1m/s around Tuvalu Island, induced by La Niña (the negative phase of ENSO); in Chile induced by the positive phase of AO; while in Guinea, Indonesia, and Papua New Guinea this increase is triggered by El Niño (the positive phase of ENSO). In addition, the wave power of westerly swells increases up to ~+10 kW/m over an average season, induced by the positive phase of AO in Ireland, Norway, and the UK; in the USA induced by El Niño; and in Australia, New Zealand, and Chile influenced by the positive phase of AAO. This framework can serve as a source of predictability and provide a basis for a proactive response to coastal impacts in anomalous seasons and be transferred to financial risk and insurance instruments.
Volcanic cloud detection and retrieval by micro-millimetre-waves and thermal-infrared satellite observations
Authors: Romeo Francesco , Mereu Luigi , Corradini Stefano , Merucci Luca , Scollo Simona
Published: February 2023

The characterization of the eruption source parameters (EPS) of explosive eruptions is of vital importance to prevent damages, mitigate environmental impact and reduce aviation risks.  We consider highly explosive eruptions with a Volcanic Explosive Index (VEI) greater than 3. During these eruptions, a great number of volcanic particles are ejected into the atmosphere where they can remain suspended for several weeks. Satellite passive sensors can be adopted to monitor volcanoes due to their high spatial and temporal resolution. In this work we combine the Microwave (MW) and Millimetre-wave (MMW) observations with Thermal-InfraRed (TIR) radiometric data from Low Earth Orbit (LEO) satellites to have a complete characterization of the volcanic clouds. MW-MMW passive sensors are adopted to detect larger volcanic particles (i.e. size bigger than 20 µm) by working at lower frequencies. TIR observations are employed to study smaller particles due to the sensor settings which work at smaller wavelengths. We describe new physical-statistical methods together with machine learning techniques aiming at detecting and retrieving volcanic clouds masses of 2015 Calbuco, 2014 Kelud as well as other eruptions having high explosive activities worldwide. Concerning the detection, we compare the well-known split-window methods with a machine learning algorithm named Random Forest (RF). This work highlights how the machine learning model is suitable to automatically identify tephra contaminated pixels by combining different spectral information (i.e. MW-MMW and TIR) coming from different satellite platforms. Indeed, we used data coming from: Advanced Technology Microwave Sounder (ATMS) and Visible Infrared Imaging Radiometer Suite (VIIRS) sensors on board the Suomi-NPP LEO satellite; Microwave Humidity Sounder (MHS) and Advanced Very High Resolution Radiometer (AVHRR) sensors on board the Metop series.  In terms of retrieval, the new developed Radiative Transfer Model Algorithm (RTMA) is designed to estimate the total columnar content (TCC) and in turn the mass, for both MW-MMW and TIR observations. The synthetic BTs (simulated by RTMA) are linked with the observed BTs to retrieve the volcanic clouds features. In this respect, two minimization techniques, the Maximum Likelihood Estimation (MLE) and the Neural Network (NN) architecture, are also compared and discussed. Results show a good comparison of the mass obtained using the MLE and NN methods for all the analysed bands but also with previous studies on the deposit as well as other validated satellite retrieval methods. In conclusion, this work shows how the machine learning model can be an effective tool for volcanic cloud detection and how the synergic use of the TIR and MW-MMW observations can give more accurate estimates of the near source volcanic cloud.
Detection and (re)location of earthquakes using Jammu And Kashmir Seismological NETwork
Authors: Shamim Sk , Ghosh Ayon , Mitra Supriyo , Priestley Keith , Wanchoo Sunil Kumar
Published: February 2023

Broadband waveform data from the recently established Jammu And Kashmir Seismological NETwork (JAKSNET) has been used to detect and locate earthquakes in the Jammu and Kashmir (J&K) Himalaya. Continuous data recorded by the network between 2015 and 2018 has been used for the analysis. The Coalescence Microseismic Mapping (CMM) algorithm is used to detect and locate hundreds of earthquakes, not reported in regional and global catalogs. These earthquakes are then relocated using a probabilistic relocation method of NonLinLoc (NLL). This produced a subset of earthquakes within 200 km of the network and having spatial uncertainty of less than 10 km. Most of the earthquakes are located beneath the Lesser and Higher Himalaya, with depth less than 25 km. A few earthquakes have depths between 30-60 km and lie across the entire region. The shallow earthquakes occur within the Himalayan wedge and define the locked-to-creep transition (unlocking) zone on the Main Himalayan Thrust. These earthquakes occur in clusters in the Jammu-Kishtwar segment, immediately south of the Kishtwar window, beneath the Kashmir Valley and in the NW Syntaxis, surrounding the 2005 (Mw 7.6) Kashmir earthquake source zone. These events provide the first evidence of the MHT locked segment beneath J&K Himalaya. The deeper events are within the underthrusting Indian crust, which reveal that the entire Indian crust is seismogenic. Double-difference algorithm is being used to improve the relative location of the shallow events to study possible clustering of earthquakes in the MHT.  
Integrating Natural Hazards into the Planning and Design of Critical Infrastructures in Urban Coastal Areas. A Case Study in Le Havre, France
Authors: Clemente Maria Fabrizia , Barroca Bruno
Published: February 2023

Critical infrastructures (CIs) have a priority role for society, the interruption or partial operation of such infrastructures can compromise the functioning of the entire city, limiting the safety and well-being of the population. In recent years, the increasing number of natural hazards, combined with the growing intensity of such phenomena, have led to long interruptions and malfunctions of CIs. These infrastructures are also interdependent and, therefore, the failure of one can cause domino effects on others.In coastal areas, CIs are subject to multiple natural hazards such as flooding, landslides, or storm surge; among them the maritime transport system represents a fundamental element of global and local economies, around 90% of international trade in goods are carried out by sea. Ports are therefore strategic nodes of this complex network; their operability must be guaranteed to not compromise the entire logistics chain.Keeping ports operational means ensuring their functional resilience also during critical climate events. To support decision-makers in planning and design, innovative models need to be developed in order to read city-port systems as complex systems and to integrate natural hazards within the projects.The contribution proposes an approach to analyze the dependencies and the interdependencies between and within the city-port systems, also in relation to other CIs (such as the energy system, road transport system or railway transport system). This approach can help decision-makers to plan measures, design uses and spaces, taking into account natural hazards considering long terms climate scenarios.The city of Le Havre, in France, will be examined as case study. A special focus will be made on the coastal areas where is located the Grand Port Maritime du Havre (GPMH), the first port in France and one of the most important ports in Europe. As indicated in the PPRL (Plans de Prévention des Risques Littoraux), the GPMH will be, in fact, at risk due to the sea level rise scenarios by 2100, so it will be necessary to implement disaster risk prevention, preparedness and reduction measures, or even relocation of infrastructures.
4C analysis of atmospheric methane: development of a portable sampling system
Authors: Zazzeri Giulia , Wacker Lukas , Haghipour Negar , Gautschi Philip , Graven Heather
Published: February 2023

Measurements of radiocarbon (14C) in atmospheric methane (CH4) provide a powerful tool to distinguish fossil from biogenic methane emissions, because fossil methane is completely devoid of 14C. However, these measurements are particularly challenging as CH4 is at low concentration in the atmosphere and large volumes of air must be sampled.At the Laboratory of Ion Beam Physics (LIP), ETH, we developed a portable sampler based on the laboratory prototype in Zazzeri et al. 2021 [1]. The new system enables extraction of carbon from CH4 while sampling in the field, reducing the sample processing in the laboratory and allowing collection of a hundred liters of air onto a 0.5 g zeolite trap.Here we present an overview of the sampling system and the technical developments that have been implemented at LIP. The relatively small size of the sampler and its interface with the gas ion source of the AMS system make 14CH4 measurements much easier to perform. Its portability will enable collection of CH4 samples in any environment, with the potential of assessing the radiocarbon signature of methane emissions that have not been yet characterized.[1] Zazzeri, G., Xu, X., & Graven, H. (2021). Environmental Science & Technology, 55(13), 8535-8541.
Terrestrial West African climate and environmental responses to orbital forcing across Neogene boundary condition changes
Authors: Lupien Rachel , Uno Kevin , Kuzina Maria , de Menocal Peter
Published: February 2023

The Sahel is highly sensitive to both floods and droughts, risking food and other resources on which nearly 100 million people depend. Understanding how natural variations of precipitation and vegetation fluctuate in response to orbital forcing across major shifts in boundary conditions, like temperature, ice volume, and land surface, can help constrain the regional sensitivity to a wide range of external forcings. However, these interactions between climate and ecosystem changes remain uncertain for sub-Saharan Africa due to the lack of long, highly resolved, quantitative, terrestrial records that span major global and regional shifts in deep time. Here we present leaf wax precipitation and vegetation records from targeted study windows throughout the last 25 million years, derived from long-chain n-alkane hydrogen (δDwax) and carbon (δ13Cwax) isotopes, respectively, in a sediment core from ODP Site 959 in the Gulf of Guinea, where westerly winds and major river systems transport Western Sahel-sourced leaf waxes. Analyses of trend, amplitude of variability, and periodicity document a range of rainfall and vegetation responses to orbital forcings, depending on the specific boundary conditions of the study window. We find that the Western Sahel got wetter, yet more C4-rich, over the Neogene. Orbital-scale precipitation was highly variable throughout the study periods, but particularly strong during the warm Miocene. While unlike many East African leaf wax isotope records that are precessionally driven, obliquity appears to play a role in the late Pleistocene, suggesting that climate-driving orbital parameters may vary regionally. Further, because of the high resolution and temporal coverage of these new biomarker isotope records, we can examine nonlinear relationships between precipitation and vegetation fluctuations, including prior to C4-expansion when we find strong correlation despite minimal variation in δ13Cwax, advancing our understanding of climate and ecosystem feedbacks millions of years ago.
Analytical model of the equatorial Magnetic-Archimedes-Coriolis waves propagating at Earth’s core surface and the potential implications
Authors: Duan Pengshuo
Published: February 2023

Modern observations show that the fast fluctuations in geomagnetic acceleration and fluid core surface flow motions always occur at the equatorial regions, which may arise from the rapidly hydromagnetic waves atop the Earth’s core. But, the exact origins of these waves are still unclear, though the so-called eMAC waves may provide a potential mechanism. Given that the physical expressions of describing the physical properties (e.g., equatorial confinement and latitudinal distribution, damping rate, eigen-period) and the perturbed magnetic fields of the eMAC waves have not been given before, this work carefully revisits the currently eMAC wave theory and firstly gives the systematically analytical expressions for these physical properties. Importantly, the perturbation analysis indicates that the eMAC wave model can own the high accuracy (i.e., the relative errors are less than 5%) to describe the low-latitude waves with latitude below 25 degrees, which can cover the regions where the equatorial waves mainly locate. In summary, this work provides an important complement for the currently eMAC wave theory. The results of this work are significant to understand the physical mechanism responsible for the origins of the inferred equatorial waves, their physical properties and the dynamics of the Earth’s equatorial regions.
Effect of land management on incorporation of prickly pear crop residues in different soil organic matter fractions of a Sicilian soil under desertification risk
Authors: Grilli Eleonora , Malrieu Iseult , Ishaq Hafiz Khuzama , D’Ascoli Rosaria , Coppola Elio , Battipaglia Giovanna , Altieri Simona , Castaldi Simona
Published: February 2023

The return of organic amendments and plants residues to the soil is a fundamental measure for carbon (C) accrual in soil, in particular in agroecosystems of Southern Mediterranean areas, where aridity limits plant growth and litter inputs as well as soil organic matter (SOM) decomposition, often resulting in land degradation and desertification risk. The allocation of this residual C in SOM fractions which are more prone to fast mineralization, at the onset of the rainy season, might significantly vary with the quality of the residues and the type of land management. The extent of residues incorporation is also relevant as it increase the SOM-microbial interactions responsible of SOM processing, mineralization and stabilization. We investigated the effect of two types of land management, no tillage and minimum tillage, on the incorporation of C from a list studied soil amendment, pruned prickly pear cladode residues, in the SOM of the same crop site, and its distribution in the particulate organic and mineral associated organic matter fractions. The characteristics 13C signature of the Opuntia ficus-indica (L.) Mill, which is an obligate CAM plant, was used to identify which of the two soil management practices was more effective in storing more C and of a more stable form along the soil profile (0-30 cm). Two adjacent cactus plantation located in southern Sicily, were used, where the different land management was maintained in the last 10 years. The analysis was part of the measures of adaptation investigated by the project Desert-Adapt (LIFE16 CCA/IT/000011) in areas under desertification risk.
Modelling the future of Nevado Coropuna (Peru), the world’s largest tropical ice cap.
Authors: Pellitero Ramón , Bonshoms Martí , Ely Jeremy C. , Liguori Giovanni
Published: February 2023

With around 46 km2, Nevado Coropuna (NC, 15°32’S, 72°39’W; 6377 m) is the largest tropical icecap in the world. NC is situated on a stratovolcano structure with six peaks over 6000 meters, in the arid border of the Andean plateau, Southern Peru. NC is a vital source of freshwater for the communities within the Majes valley and the vast irrigation plans located in the same valley and on the arid coastal strip. Our MOTICE project will model the evolution of NC until 2100 CE in response to climate change.We present initial results on the modelling of NC, which will be used to tune the glaciological parameters for the projections under different RCP scenarios. Mass balance was modelled using the COupled Snowpack and Ice surface energy and MAss balance model in Python (COSIPY). This was forced with climate data for the 1950-2020 period from the ERA5-Land reanalysis, which provided surface pressure, cloud cover, incoming shortwave and longwave radiation, wind speed, 2-meter air temperature and relative humidity fields. This was combined with the RAIN4PE gridded product outputs for daily precipitation during the 1981-2015 period. The climate dataset was downscaled and validated with observed temperature and relative humidity from a weather station located on the Cavalca glacier (5800 m above sea level), at the northern part of NC. Glacier mass balance results were validated with measured mass balance in the same glacier for the 2014-2019 period. The mass-balance outputs from COSIPY were used for glacial flow modelling, using the Parallel Ice Sheet Model (PISM).Subglacial topography was modelled using the Volume and Topography Automation (VOLTA) tool in a DEM that had been previously corrected with 70 differential GPR points measured “in situ”. The subglacial topography was also tuned and validated against in-situ GPR measurements in four glaciers of NC. Both GPR and GPS measurements were conducted during the 2022 fieldwork campaign, in which large areas of debris-covered ice were also located, mapped and measured. However, debris covered ice has not been considered in this initial model run.Our preliminary results were compared to the actual 1955-2020 glacier surface evolution, which was retrieved from aerial photography and topographic maps for the initial stage in 1955 and from satellite images from 1975 onwards. This work highlighted the difficulty of modelling tropical glaciers, especially accounting for processes important to tropical ice, such as sublimation, and short-lived meteorological events.
Evapotranspiration measurements on an eroded cropland using an automated and mobile chamber system: gap filling strategies and impact of soil type and topsoil modification
Authors: Dahlmann Adrian , Hoffmann Mathias , Verch Gernot , Schmidt Marten , Sommer Michael , Augustin Jürgen , Dubbert Maren
Published: February 2023

In light of the ongoing global change in climatic conditions and a related trend to increases in extreme hydrological events, it is increasingly crucial to assess ecosystem resilience and - in agricultural systems - to ensure sustainable management and food security.  A comprehensive understanding of ecosystem water cycle budgets and spatio-temporal dynamics is indispensable. Evapotranspiration (ET) plays a pivotal role returning up to 90 % of ingoing precipitation back to the atmosphere. Here, we studied impacts of soil types and management on an agroecosystem's water budgets and agronomic water use efficiencies (WUEagro). To do so, a plot experiment with winter rye (September 17, 2020 to June 30, 2021) was conducted at an eroded cropland which is located in the hilly and dry ground moraine landscape of the Uckermark region in NE Germany. Along the experimental plot (110 m x 16 m), a gantry crane mounted mobile and automated two chamber system (FluxCrane as part of the AgroFlux platform within the CarboZALF-D research site) was used for the first time to continuously measure water fluxes and determine evapotranspiration. Three soil types representing the soil erosion gradient related to the hummocky ground moraine landscape (extremely eroded: Calcaric Regosol, strongly eroded: Nudiargic Luvisol, non-eroded: Calcic Luvisol) and additional soil manipulation (topsoil removal and subsoil admixture) were investigated (randomized block design, 3 replicates per treatment). Five different gap-filling approaches were used and compared in light of their potential for reliable water budgets over the entire crop growth period as well as reproduce short-term (day-to-day, diurnal) water flux dynamics. The best calibration performance was achieved with approaches based on machine learning, such as support vector machine (SVM) and artificial neural networks (with Bayesian regularization; ANN_BR), while especially SVM yielded in most reliable predictions of measured ET during validation.We found significant differences in dry biomass (DM) and minor in evapotranspiration between soil types, resulting in different water use efficiencies (WUEagro). The Calcaric Regosol (extremely eroded) shows a maximum of around 37% lower evapotranspiration and a maximum of around 52% lower water use efficiency (WUEagro) compared to the non-eroded Calcic Luvisol.  The key period contributing to ~ 70% of overall ET of the entire growth period was from April until June (harvest), however differences in the overall ET budget (ETsum) between soil types and manipulation resulted predominantly from small differences between the treatments over the entire growth period. 
An approach to relate uranium to indoor radon: a case study from the western Ligurian Alps (Italy)
Authors: Bonorino Linda , Beccaris Gianluca , Bisi Paola , Chiozzi Paolo , Cogorno Andrea , Filippi Elga , Narizzano Riccardo , Prandi Sonja , Verdoya Massimo
Published: February 2023

Radiometric surveys are used to investigate different scientific and practical issues in Earth’s science studies, ranging from basic geophysics to mineral exploration and natural radiation monitoring. The latter is a topic of growing interest. 238U, 232Th and 40K, which occur in variable quantities in the Earth’s crust rocks, are the primary cause of natural, potentially hazardous, gamma-ray exposure. Another important environmental aspect of natural radioactivity regards the effects of  222Rn resulting from the 238U decay. This paper proposes an experimental approach to investigate the relationship between uranium and indoor radon concentration. We combined ground gamma-spectrometry with alpha-track detector measurements. We tested this methodology in the Alpine geological units of western Liguria (Italy). This area is densely populated and characterised by various lithotypes, spanning from sedimentary to metasedimentary and metavolcanic rocks. The latter are known for their abundance of natural radionuclides. Due to the width of the surveyed area (408 km2), we carried out about 300 gamma-ray determinations on the more extensive geological formations, with particular reference to those hosting the main residential areas, together with about 130 measurements of indoor radon. By considering the nineteenth percentile of the recorded specific activity, the largest value of 238U was 93 Bq/kg. It was found in the more acid metamorphic rocks (metarhyolites and porphyric schists) where we carried out also the largest number of gamma-ray spectrometry measurements. In the metasedimentary rocks, the largest activities of 238U were observed in quartzschists and micaschists (89 Bq/kg). In the sedimentary lithotypes, specific activities are generally lower than 40 Bq/kg. We found that the number of buildings with 222Rn exceeding 200 Bq/m3 increases where the specific activity of 238U is larger. About 40% of dwellings and public buildings with 222Rn>200 Bq/m3 occurs in the lithotypes (metarhyolites and micaschists) with 238U>60 Bq/kg. A comparison between the indoor 222Rn concentration and the 238U specific activity measured on the same geological formation showed a linear correlation. Using the records of 238U specific activity, we developed a map of the expected radon concentration on the different geological formations of the surveyed area. Despite the limitations and uncertainties, mainly related to the uneven data coverage and the complex interaction between the building and the bedrock, the proposed approach showed that gamma-ray spectrometry can be a valuable tool to identify areas of more significant potential risk of radon emanation.
The costs of the emergency and the role of the Court of Auditors
Authors: Manzetti Vanessa , Colombini Giovanna , Carpita Francesca , Colangelo Letizia
Published: February 2023

This paper aims to highlight how the Italian Court of Auditors can help to detect the costs of the recent pandemic emergency. The Court of Auditors is assigned the scrutiny of the economic-financial balance of the Public administrations in order to protect the economic unity of the Italian Republic.  Such prerogatives have a great importance in the framework outlined by art. 2 §1 of the Constitutional Law n.1/2012, which, in line with the European Union legal system, recalls the Public Administrations as a whole to ensure balanced budgets and the sustainability of the public debt. This means that the surveys of the Court of Auditors in the performance of its functions (judicial, control and advisory) should indirectly also reveal the emergency costs. The paper will examine some fundamental documents such as the Report on the financial management of the local authorities 2019-2021, the deliberations of the Regional Audit sections of the Court on budgets of the local health authorities, as well as the Reports on the result of the controls on the financial management of the companies subject to the control of the Court of Auditors ex art. 12 of the Law n. 259 of 1958. The exam will also focus on the controls that the Regional Control Sections of the Court of Auditors carries out on the budgets and final accounts of Local Authorities to verify the compliance with the annual objectives set by the Internal Stability Pact and the compliance with the obligation provided by article 119 § 6 of the Italian Constitution. These controls aim also to verify the debt sustainability and the absence of irregularities that could jeopardize the balance economic-financial aspects of the Local Authorities. An important perspective to better quantify the costs of the emergency is also identified by article 103 of the Italian Constitution which attributes to the Court of Auditors the jurisdiction on public accounting, civil, military and war pensions, as well as the jurisdiction on the liability of public accountants, public administrators and public officials in judgements concerning the management of the public money. This approach could also lead to reflect on the relationship between public debt and emergency, and on the possibility of judgments raised by a party before the Court of Auditors. Lastly, the examination of the Opinions drawn up by the Court of Auditors in the exercise of its advisory function could be also useful to trace the unclear perimeter of the costs of the emergency.   The work consists of two parts: a general part carried out by Professors Giovanna Colombini and Vanessa Manzetti and a part of analysis of case studies carried out by Dr. Francesca Carpita and Dr. Letizia Colangelo. 
Industrial Atmospheric Pollution Estimation Using Gaussian Process Regression
Authors: Sokolov Anton , Delbarre Hervé , Boldyriev Daniil , Bulana Tetiana , Molodets Bohdan , Grabovets Dmytro
Published: February 2023

Industrial pollution remains a major challenge in spite of recent technological developments and purification procedures. To effectively monitor atmosphere contamination, data from air quality networks should be coupled with advanced spatiotemporal statistical methods.Our previous studies showed that standard interpolation techniques (like inverse distance weighting, linear or spline interpolation, kernel-based Gaussian Process Regression, GPR) are quite limited for the simulation of a smoke-like narrow-directed industrial pollution in the vicinity of the source (a few tenths of kilometers). In this work, we try to apply GPR, based on statistically estimated covariances. These covariances are calculated using СALPUFF atmospheric pollution dispersion model for a one-year simulation in the Kryvyi Rih region. The application of GPR permits taking into account high correlations between pollution values in neighboring points revealed by modeling. The result of the GPR covariance-based technique is compared with other interpolation techniques. It can be used then in the estimation and optimization of air quality networks.