bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-sensor 3D mapping of Tethys Bay (Ross Sea – Antarctica) with PROTEUS, an innovative, highly reconfigurable and versatile unmanned marine vehicle
Authors: Bruzzone Gabriele , Aracri Simona , Bibuli Marco , Bruzzone Giorgio , Caccia Massimo , Ferretti Roberta , Giacopelli Mauro , Ivaldi Roberta , Motta Corrado , Odetti Angelo , Spirandelli Edoardo , Zereik Enrica
Published: February 2023

During the XXXVIII Italian Expedition in Antarctica, in the framework of the PNRA RESTORE (Robotic-based invESTigation and mOnitoring Ross sEa) project the PROTEUS (Portable RObotic TEchnology for Underwater Surveys) unmanned marine vehicle (UMV) was used for carrying out an integrated 3D mapping of a portion of the Tethys Bay in the Ross Sea. PROTEUS is an innovative UMV developed by the Marine Robotics research group of CNR-INM which is particularly suitable, with its reduced size and weight, modularity, reconfigurability, and open hardware and software architectures, to operate in extreme environments as the polar ones. For performing the survey seven holes were drilled in the ice pack from which it was possible to deploy the robot in the water. Thanks to the versatility of PROTEUS, it was possible to acquire a comprehensive collection of bio-geo-chemical and physical parameters of the water column (acoustic, conductivity/salinity, temperature, depth, dissolved oxygen, turbidity and chlorophyll), acoustic and video data of the ice and the seabed. All the collected data, once processed, will be made available to the scientific community by means of FAIR (Findable, Accessible, Interoperable and Reusable data) techniques following the UN Ocean Science Decade directives.
A Broadband Cavity-Enhanced Absorption Spectrometer for Simultaneous measurements of NO2 and particulate matter
Authors: Chen Weidong , Wang Gaoxuan , Meng Lingshuo , Gou Qian , Hanoune Benjamin , Crumeyrolle Suzanne , Fagniez Thomas , Coeur Cécile , Akiki Rony
Published: February 2023

A novel instrument based on broadband cavity enhanced absorption spectroscopy has been developed using a supercontinuum broadband light source, which showcases its ability in simultaneous measurements of the concentration of NO2 and the extinction of particulate matter (PM). Side-by-side intercomparison was carried out with the reference NOx analyzer for NO2 and OPC-N2 particle counter for particulate matter, which shows a good linear correlation with r2 > 0.90. Measurement limits (1σ) of the developed instrument were experimentally determined to be 230 pptv in 40 s for NO2 and 1.24 Mm-1 for the PM extinction in 15 s, respectively.This work provides a promising method in simultaneously monitoring atmospheric gaseous compounds and particulate matter, which would further advance our understanding on gas-particle heterogeneous interactions in the context of climate change and air quality.Experimental details and the preliminary results will be discussed and presented. AcknowledgmentsThe authors thank the ﬁnancial supports from the French national research agency (ANR) under the MABCaM (ANR-16-CE04-0009), the CaPPA (ANR-10-LABX-005) contracts, the CPER ECRIN program, and the EU H2020-ATMOS project.
Snow insulation effects on soil surface temperatures in a snow-fence manipulation experiment
Authors: Liu Yijing , U. Hansen Birger , Elberling Bo , Westergaard-Nielsen Andreas
Published: February 2023

Seasonal snow cover is a key control on winter soil temperature (Tsoil) in the Arctic because of its insulating effects. It is still uncertain how variations in soil moisture, climate warming, and vegetation types affect this insulating effect and thus the difference between Tsoil and air temperature (ΔT). In this study, we present an analysis of 8 years (2012–2020) of snow dynamics in an Arctic ecosystem manipulation experiment (using snow fences) on Disko Island, West Greenland. We explore the snow insulation effects under four different treatments ((1) mesic tundra heath as a dry site and fen area as a wet site, (2) snow addition because of the snow fence, (3) summer warming using open-top chambers, and (4) shrub removal) on a plot level scale. The ΔT at 5-cm soil depth (ΔT5) was higher on the snow addition side than on the control side of the snow fences. The ranges of maximum weekly ΔT5 and annual mean accumulated daily ΔT5 were from 11.2 to 19.3 ℃ and 1297 to 1631 ℃ on the control side, and from 14.4 to 22.1 ℃ and 1372 to 1830 ℃ on the snow addition side across all study years, respectively. Based on linear mixed-effects models, we conclude that the snow depth was the decisive factor affecting ΔT5 (p < 0.0001) with a coefficient of 0.05, and found the ΔT5 to be 1.93 ℃ higher (p < 0.0001) in the wet site than in the dry site during the snow cover season. The change rate of ΔT5 as the function of snow depth varies with the evolution of snow cover, it is quicker during the period between the day with maximum snow depth to the last day with snow in most experimental plots. During the snow-free season, there were certain lagged effects of the snow cover on Tsoil and they offset the warming effects from open-top chambers and shrub removal, i.e., the combination of warming and removal treatments could increase ΔT5 by 1.71 ℃ on the control side but only 0.83 ℃ on the snow addition side in the dry site. However, the effects of warming and removal treatments on Tsoil are limited in the wet site because of a higher soil water content. This study quantifies important dynamics in soil-air temperature offsets linked to both snow and ecosystem changes mimicking climate change and provides a reference for future surface process simulations.
Tropical Climate Variability and Coral Reefs - A Past to Future Perspective on Current Rates of Change at Ultra-High Resolution
Authors: Felis Thomas , Pfeiffer Miriam , Hargreaves Jessica ,   SPP2299 Programme
Published: February 2023

Climate change, in particular the rise in tropical sea surface temperatures, is the greatest threat to coral reef ecosystems today and causes climatic extremes affecting the livelihood of tropical societies. Assessing how future warming will change coral reef ecosystems and tropical climate variability is therefore of extreme urgency. Ultra-high resolution (monthly, weekly) coral geochemistry provides a tool to understand the temporal response of corals and coral reefs to ongoing climate and environmental change, to reconstruct past tropical climate and environmental variability, and to use these data in conjunction with advanced statistical methods, earth system modelling and observed ecosystem responses for improved projections of future changes in tropical climate and coral reef ecosystems. The recently established Priority Programme “Tropical Climate Variability and Coral Reefs - A Past to Future Perspective on Current Rates of Change at Ultra-High Resolution” (SPP 2299, https://www.spp2299.tropicalclimatecorals.de/) of the German Research Foundation (DFG) aims to enhance our current understanding of tropical marine climate variability and its impact on coral reef ecosystems in a warming world, by quantifying climatic and environmental changes during both the ongoing warming and past warm periods on timescales relevant for society. The programme aims to provide an ultra-high resolution past to future perspective on current rates of change to project how tropical marine climate variability and coral reef ecosystems will change in a warming world. Information on the organisational structure and research topics of this collaborative programme, which involves ten universities and five research centres from all over Germany, will be provided.
Structural uncertainty in full-plate reconstructions as a way to account for lost intra-oceanic plate boundaries
Authors: Merdith Andrew , Arnould Maëlis
Published: February 2023

The past decade has seen the rise of fully kinematic palaeogeographic models that explicitly define the evolution of both plate boundaries and tectonic plates. Included in these models are (possible) interpretations of spreading systems in extinct ocean basins. Typically, the primary constraint on controlling these synthetic mid-ocean ridges is ensuring that at known (i.e. preserved in the geological record) subduction zones there is convergence, and that at modelled mid-ocean ridges there is divergence. The most common way this is expressed in models is through a quasi-stable triple junction. While obviously subject to large inherent uncertainties, the advantage of modelling such ocean basins is that they can provide an internally consistent model of (tectonic) ocean evolution, tied to the underlaying palaeomagnetic and palaeotectonic framework. Here we explore this inherent uncertainty in such synthetic ocean basins, by introducing the concept of ‘structural uncertainty’ within a full-plate model. We describe structural uncertainty as the answer to the question, “how much oceanic-oceanic subduction (i.e. not preserved in the geological record) is required to balance the modelled synthetic spreading ridges?” While an initial inclination that models tending to ‘zero’ might be best, we entertain the possibility that there is a range of ‘lost’ subduction. To assess this hypothesis, we also interrogate whole-mantle convection models that produce self-consistent plate tectonics to determine the proportion of subduction around or adjacent to continents (representative of what might be preserved in the geological record), and subduction occurring within ocean basins (representative of what might be lost to the geological record).
Evaluation of the mechanism of residence time change of Shimabara springs based on high frequency water sampling survey
Authors: Ishibashi Miku , Sakakibara Koichi , Kagabu Makoto
Published: February 2023

It is essential to clarify the groundwater flow system and its scale for the sustainable use and management of local water resources. One effective method is to estimate the residence time of groundwater. The Shimabara springs exist in Nagasaki Prefecture, Japan, and its water quality has been characterized over time. However, there have been few studies on water quality characteristics and isotope variations with fine resolution in a region such as Japan, where seasonal changes in precipitation are observed. Therefore, we conducted periodic water sampling at five locations in the Shimabara Springs at a frequency of about once a month, and evaluated water quality characteristics and isotope variations. CFC-12, an age dating tracer, was also used for a multifaceted study. During the observation period, we observed precipitation that was more than five times larger than the normal year, and in response to this, we were able to identify springs that showed changes in various hydrologic parameters. In the presentation, we will discuss the relationship between precipitation, residence time, and water quality, and present a schematic diagram of the mechanism of this spring discharge.
Nutrient dynamics in fen peat in relation to water level management: a mesocosm experiment
Authors: van der Laan Annick , van Dijk Jerry , Rebel Karin , Wassen Martin
Published: February 2023

Peatlands are valuable ecosystems that hold a high biodiversity and provide many ecosystem services such as carbon sequestration, water storage and water purification. However, a large part of the peatlands are drained, often for agricultural purposes, resulting in CO2 emissions, soil subsidence and biodiversity loss. To combat these negative effects, various rewetting measures are being installed which can be combined with varying land-uses such as intensive dairy farming, extensive agriculture, semi-natural grasslands, paludiculture (farming on moist/wet soils) and nature restoration. This broad applicability implies that the extent by which the groundwater level is raised can be fine-tuned to the intended land use. In our study, we conducted a mesocosm experiment in which we exposed intact fen peat cores (80cm, 20cm Ø) to five different water levels (0, 20, 40, 60 cm and variable - surface), two nutrient application levels and two water qualities. For an eight-month period, monthly samples from each peat core were taken at two depths and chemically analyzed. Further, the vegetation in the cores was cut five times throughout the growing season. Above-ground biomass was measured as well as nutrient concentrations in the vegetation. Our results show increased phosphate and ammonium availability upon fully rewetting (0 cm – surface), in contrast to partially rewetted circumstances (20cm – surface) where nutrient availability was lowest. Above-ground biomass was strongly affected by nutrient application and, except for early spring growth, less by water levels. Nitrogen concentrations in the vegetation decreased with increasing water levels indicating stronger nitrogen limitation. This is likely the result of increased denitrification rates under wet circumstances. We conclude that in order to achieve nature restoration under fully rewetted conditions, additional steps must be taken to remove nutrients, particularly phosphorus, from the system. Further, we conclude that partial rewetting can be a solution to slow down the adverse effects of drainage, although agricultural production will decrease. 
Quantifying statistical associations among persistent events: Interval coincidence analysis between Northern hemisphere heatwaves and different types of circulation anomalies
Authors: Donner Reik , Diedrich Dominik , Praast Sven , Di Capua Giorgia
Published: February 2023

Statistical associations between variables of interest are commonly assessed by applying similarity measures like Pearson correlation to corresponding observational time series. Most traditional measures focus on continuous variables and their associated complete variability, while there is a vast amount of practical examples where only times with specific conditions (e.g. extreme events) are of interest. For the latter cases, concepts like event synchronization strength or event coincidence rates have been introduced as proper similarity measures, and have proven their broad applicability across many areas of research. However, recent work has shown that such event based similarity measures may have conceptual as well as practical limitations when studying co-occurrence statistics between temporally clustered or extended events that do not meet the common assumption of serially uncorrelated point processes.In this work, we introduce and discuss a straightforward extension of event coincidence analysis (ECA) to studying statistical associations between sequences of persistent events, which we tentatively call interval coincidence analysis (InCA). Here, each event of interest corresponds to a well-defined time interval, and the discrete counts of event co-occurrences in ECA are replaced by the fractions of time during which event intervals in two sequences mutually overlap. A statistical significance test for the obtained interval coincidence rates is realized by block bootstrapping event and non-event intervals, retaining the event duration and waiting time distributions of the persistent events in both sequences.We demonstrate the practical potentials of InCA, as well as its similarities and differences with ECA, for a specific case study on atmospheric dynamics. Specifically, we apply both methods to studying the likelihood of co-occurrences between boreal summer (June to August) heatwaves in different parts of the Northern hemisphere and hemispheric anomalies of the atmospheric circulation, such as a jet stream pattern exhibiting two distinct wind bands known as double-jet. Our analysis reveals large-scale regions of markedly elevated likelihood of co-occurrences over Northern Europe, Central to Eastern Siberia, Northeastern Canada as well as the Middle East, Eastern China, the Southwestern and Northeastern United States and Northwest Africa, indicating a particular vulnerability of those regions to the presence of double-jet patterns.
Grain shape effects in bed load sediment transport
Authors: Deal Eric , Venditti Jeremy , Benavides Santiago , Bradley Ryan , Zhang Qiong , Kamrin Ken , Perron Taylor
Published: February 2023

Predictions of bed load sediment flux are notoriously imprecise despite widespread occurrence and importance in contexts ranging from river restoration to planetary exploration. Natural variations in grain size, shape and density are possible sources of inaccuracy in sediment transport, as well as mixtures of different grain sizesand time-dependent bed structure. While many of these effects have been studied in depth, the effects of grain shape have rarely been quantified, even though shape has long been hypothesized to influence sediment transport.During bed load transport, the granular bed is sheared by the flow passing over it. Aspherical grains and rough surfaces generally increase the resistance to such shearing, enhancing frictional resistance, and reducing the efficiency of bed load transport. However, aspherical grains also experience higher fluid drag force than spherical grains of the same volume, enhancing transport efficiency under the same flow conditions. These two competing effects generally get stronger as grain shape deviates from spherical, making it challenging to predict the net effect of grain shape on sediment transport. We disentangle these competing effects by formulating a theory that accounts for the influence of grain shape on both fluid-grain and grain-grain interactions. It predicts that the onset and efficiency of transport depend on the average coefficients of drag and bulk friction of the transported grains. Because we use the average statistics of drag and friction to characterize the effect of grain shape, our approach is also applicable to materials like natural gravel that have many different shapes in the same sample.Using a series of flume experiments with different granular materials of distinct shapes, we show that grain shape can modify bed load transport rates by an amount comparable to the scatter in many sediment transport data sets. Our data also demonstrates that, although bed load transport of aspherical grains is generally inhibited by higher bulk friction and enhanced by higher fluid drag, these two effects do not simply cancel each other. This means that the effect of grain shape on sediment transport can be difficult to intuit from the appearance of grains, with the possibility for grain shape changes to lead to either a reduction or an enhancement of sediment transport efficiency.
Use of Anionic Polyacrylamide to improve soil properties and challenge slope instabilities: preliminary data
Authors: Frutaz Giulia , Meisina Claudia , Bordoni Massimiliano , Sorgenti Rinaldo
Published: February 2023

Nowadays, changing climate is continuously posing new challenges to land management and conservation, also in built areas and agricultural fields. Polymers such as polyacrylamide (PAM) offer a suitable tool to stem soil degradation, as well as having a wide range of applications. We performed a detailed investigation about this polymer applications with particular attention to the field of slope instabilities through a systematic literature review to assess the extent and the specifics of the research done on Polyacrylamide as an improver of soil features, browsing between more than 800 articles published from 1990 to 2022. Research on polyacrylamide application increased since the 2000s, its main use being the prevention of irrigation-connected erosion, even if in more recent years its ability as a soil stabilizer became more and more newsworthy. We then proceeded to reconstruct soil samples in laboratory to observe the effects of application of anionic polyacrylamide (PAM) on their physical, volumetric, mechanical, and hydrological properties. First, two sets of samples were reconstructed using kaolin and sandy loam soil, respectively, with three different dry densities (varying between 1.2 and 1.6 g/cm3), three different initial water contents (varying between 10% and 40%) and five different polymer application rates (0%, 0.003%, 0.03%, 0.3%, and 1%by weight). The polymer, a granular anionic polyacrylamide, provided by Micronizzazione Innovativa Srl, has been manually applied and mixed with the samples, constituted by pvc cylinders with a diameter of 9.5 cm and 15 cm high. Preliminary results showed that the increase of PAM percentage in samples generally coincided with increase of liquid limit and plasticity index, causing at the same time a more gradual and regular release of samples water compared to untreated samples. These preliminary results can stress on the possible application of PAM to improve other soil features which could impact on slope instabilities occurrence, in a frame of sustainable solutions for reduction of landslides susceptibility, hazard and risk.  Keywords PolyacrylamideLandslidesSoil conservationLand degradation
Three-dimensional maps of a heterogeneous peridotite of the Cima Lunga unit: resolution of lithological limits and geological implication (Central Alps, Switzerland)
Authors: Schenker Filippo Luca , Zwahlen Jodok , Spataro Alessio
Published: February 2023

Remote sensing helps to evaluate quantitatively geological processes by increasing the precision of 3D geological maps, especially in areas that are poorly accessible. Here, we investigate the feasibility and the maximum obtainable resolution of digital geological maps of a heterogeneous High-Pressure ultramafic body (length of ca. 300 m) embedded within paragneisses of the Cima Lunga unit (Central Alps, Switzerland). The peridotite contains deformed mafic layers of amphibolite, eclogite, metarodingite or eclogitic metarodingite. Furthermore, calcsilicate layers locally cut the peridotite and are usually interpreted as ophicalcites that formed on the seafloor, prior to Alpine deformation and metamorphism.Remote sensing data was acquired by an unmanned aircraft system (UAS) and elaborated with the software Aegisoft Photoscan for the image mosaic, Cloud compare for the Digital Elevation Model and QGIS for the visualizations. The model was georeferenced using ground control points, whose exact coordinates were obtained in the field using a GPS (with errors of ± 3 cm). In a first step, we mapped the ultramafic body using the 3D model, the orthoimages and the published geological data. In a second step, we mapped the ultramafic body in the field using our high-precision 3D topographic model (scale 1:1’000). In a last step, we fused the two maps and compared the different approaches in terms of precision of geological boundaries, lithological content and of work efficiency.The results show that the map interpreted with the digital 3D model yields a high accuracy of the main ultramafic body (<1 m). However, internal small-scale geological features (e.g. mafic dikes <1.5 m) are very hard to distinguish, unless known from prior work. In addition, mapping with UAS images only is not reliable in suboptimal terrain such as loose rocks, grassy ledges, area with large light contrasts, etc.In comparison, field mapping yielded a much more detailed map with lithological details up to 0.3 m, but the uncertainties of the lithological limits varied from 2.5 to 5 m associated with the precision of the localization in the field. In addition, the field observations helped with the geological interpretation across the partially covered outcrops. However, such an approach was time-consuming.The fusion of both approaches combined the precision of the 3D model (<1 m) with the resolution of the fieldwork and allowed to resolve features as small as 0.3 m.Finally, the final 3D map helped to clear up a geological feature: The calcsilicates cannot be considered metamorphosed ophicalcites that formed at the seafloor. Indeed, the map shows that calcsilica-breccias and migmatitic leucogneisses (presumably Alpine in age) together intruded the necking zones of the boudinaged ultramafic body, locally cutting the foliation of the peridotite.
The southward expansion rate of the desertification in the Adamawa Plateau (Central Cameroon): implication for the speed of the Sahel desertification progress in Central Africa
Authors: N'nanga Alexandrine , Anselmetti Flavio S.
Published: February 2023

Central Africa experiences desertification hazards mostly due to deforestation in context with climate change and human activities like iron melting and agricultural practices. However, one of the most severe obstacles for sustainable development in Central Africa is the Sahel desertification whose speed of progress is underexplored. Among multiple lines of evidence recorded in geological archives, which suggest its southward progress in Central Cameroon over the Anthropocene epoch, the southward shift of the Intertropical Convergence Zone since 3.6 kyr BP is the most warning signal followed by forest disruption in favor of savannah expansion. This project aims at estimating the speed of the Sahel desertification progress in Central Africa, by quantifying its progress rate in Central Cameroon located between the sahelian zone, to the north, and the equatorial zone, to the south. For this purpose, four lake-sediment cores were collected in four shallow lakes on the Adamawa Plateau. They are investigated for sedimentology, geochemistry, mineralogy, and radiocarbon chronology. The goal of this study is to characterize the sedimentary sequences, pinpoint related environmental change in sediment supply and source area and differentiate relevant paleoclimate indicators of intensification of dry conditions over time. The importance of these centennial to decadal natural trends and variations as well as possible effects of human activities will contribute to a better understanding of the Sahel desertification progress in Central Africa.
Seismic Monitoring of Permafrost Dynamics at Mt. Zugspitze (German/Austrian Alps)
Authors: Lindner Fabian , Smolinski Krystyna , Scandroglio Riccardo , Fichtner Andreas , Wassermann Joachim
Published: February 2023

As observed elsewhere on a global scale, mountain permafrost at the Zugspitze (German/Austrian Alps) is degrading in response to climate change, which affects the rock slope stability and thus the hazard potential. Recent studies suggest that passive seismology is a promising and emerging tool to monitor permafrost changes as the seismic velocity of rocks strongly decreases/increases upon thawing/freezing. Compared to other, more classical methods like borehole temperature logging or electrical resistivity tomography (ERT), seismology is less laborious and costly, non-invasive and allows continuous monitoring. At Mt. Zugspitze, we exploit these advantages using a permanent seismic station (installed in 2006) as well as three small seismic arrays and Distributed Acoustic Sensing (DAS; both available since summer/fall 2021), to infer permafrost dynamics with high spatio-temporal resolution. The seismic data show repeating diurnal noise generated by the operation of cable cars, which we leverage for cross-correlation analysis. Our results suggest that the dominant signal in the retrieved seismic velocity change time series is caused by the seasonal freeze-thaw cycles associated with permafrost bodies on the northern side of the mountain ridge. On the long-term, the time series show a gradual velocity decrease associated with permafrost degradation due to atmospheric warming and compare well with modeled velocity change time series using rock temperature data from a nearby borehole, which intersects the mountain ridge. We discuss differences in our seismic analysis results obtained from direct and coda waves as well as from single station to station pairs and DAS and interpret the results in the light of other measurements including ERT, rock temperature logging and meteorological parameters.
Multi-source UAV remote sensing and AI for crop growth monitoring
Authors: Sun Zhigang , Zhu Wanxue , Eyshi Rezaei Ehsan , Peng Jinbang , Yu Danyang , Siebert Stefan
Published: February 2023

Accurate and in-time monitoring of cropping systems is critical to precision farming in order to facilitate decision-making for agronomic management and enhancing crop yield under changing climate. In this study, multi-source unmanned aerial vehicle (UAV) remote sensing observations were conducted at several key growing stages of crops at a standard wheat-maize cropping system field trials in the North China Plain from 2018 to 2020. Crop leaf area index, above-ground biomass, chlorophyll content, grain yield, and plant density were estimated using multi-source UAV remote sensing observations (including RGB, multi/hyperspectral, LiDAR, and thermal sensors) processed by machine/deep learning approaches.In this study, we will give a comprehensive research introduction focusing on how to improve the estimation accuracy of the above crop growth variables via UAV remote sensing and machine/deep learning approaches, including three aspects:(1) Data source and fusion, including the integration of multi-source UAV information for comprehensive maize growth monitoring, comparison of UAV-based point clouds with different densities for crop biomass estimation, and crop chlorophyll content estimation using multi-scale hyperspectral information.(2) Optimization of UAV observation management: we will answer when is the most relevant phenological stage for maize yield estimation via high-frequent UAV observations; investigate extrapolation artefacts, validate the suitability and discuss the uncertainty of the UAV-based strategies for 'model calibration at a small site while applying these models at a large extent' for crop monitoring.(3) Modeling improvement will give two cases to introduce improving crop biomass estimation accuracyand realize the plant density counting during the vigorous growing period employing deep learning.
A deep machine learning approach to predict Sea Surface Temperature and Marine Heatwaves occurrences over the Mediterranean Sea
Authors: Bonino Giulia , Masina Simona , Galimberti Giuliano , Clementi Emanuela
Published: February 2023

Marine Heat Waves (MHWs) have significant social and ecological consequences. There is a growing need to predict these extreme events to prevent and possibly mitigate their negative impacts and to better inform decision-makers on MHWs-related risks. In this context, we applied Long Short-Term Memory (LSTM) networks to predict Sea Surface Temperature (SST) time-series and, in turn, MHWs, over the Mediterranean Sea. LSTM networks are types of recurrent neural networks capable of learning order dependence in sequence prediction problems, and they have been widely applied in temperature forecasting problems. The model is a multi-step LSTM model, which means that it predicts seven time-steps of SST into the future. In order to build an efficient prediction model, as input times-series, LSTM exploits SST together with other relevant atmospheric variables (e.g. Geopotential Height, Incoming solar radiation), selected as potential MHWs drivers. The datasets used to train and to test the model are the European Space Agency (ESA) Climate Change Initiative (CCI) Sea Surface Temperature (SST) v2.1 for SST and ERA5 reanalysis for the atmospheric components from 1981 to 2016.  Preliminary results over target areas suggest that, besides the SST itself, the incoming solar radiation has the highest predictive skill on SST variability with respect to the other atmospheric variables. The model is accurate in predicting the occurrence of MHWs in the test dataset at the earliest days of forecast. In addition, the root mean square error analysis between predicted and actual SST time-series shows that LSTM models errors compare favorably with respect to the Copernicus Mediterranean Forecasting System (MedFS, i.e. dynamical model) errors, at least at the earliest days of forecast.
Aerobic methanotrophic bacteria cause carbonate corrosion at a marine methane seep
Authors: Birgel Daniel , Cordova-Gonzalez Alexmar , Wisshak Max , Urich Tim , Brinkmann Florian , Bohrmann Gerhard , Marcon Yann , Peckmann Jörn
Published: February 2023

Methane seeps are typified by authigenic carbonate formation. Many seep carbonates exhibit corrosion surfaces and secondary porosity, which are believed to be caused by microbial carbonate dissolution. Aerobic methane oxidation and sulfur oxidation are the two most likely processes capable of inducing carbonate corrosion at methane seeps. Although the potential of aerobic methanotrophy to dissolve carbonate was confirmed in laboratory experiments, this process has not been studied in the environment to date. Here, we report on a carbonate corrosion experiment carried out in the REGAB Pockmark, Gabon-Congo-Angola passive margin, in which marble cubes were deployed for 2.5 years at two sites (CAB-B and CAB-C) with apparent active methane seepage and one site (CAB-D) without methane seepage. Marble cubes exposed to active seepage (experiment CAB-C) were found to be affected by a new type of microbioerosion. Based on 16S rRNA gene analysis, the biofilms adhering to the bioeroded marble mostly consisted of aerobic methanotrophic bacteria, predominantly belonging to the uncultured Hyd24-01 clade. The presence of abundant 13C-depleted lipid biomarkers including fatty acids (n-C16:1ω8c, n-C18:1ω8c, n-C16:1ω5t), various 4-mono- and 4,4-dimethyl sterols, and diplopterol agrees with the dominance of aerobic methanotrophs in the CAB-C biofilms. Among the lipids of aerobic methanotrophs, the uncommon 4α-methylcholest-8(14)-en-3β,25-diol is interpreted to be a specific biomarker for the Hyd24-01 clade. The combination of textural, genetic, and organic geochemical evidence suggests that aerobic methanotrophs are the main drivers of carbonate dissolution observed in the CAB-C experiment at the REGAB pockmark.
Using a seismic array to study sediment redistribution after dam breaching
Authors: Chang Tzu-Yao , Chao Wei-An , Hung Chi-Yao
Published: February 2023

In the case of dam breaches in natural rivers, there is a lack of systematic studies understanding how the changes in the river bed elevation. This study aims to understand the characteristics of erosion and deposition along the river channel. Two field-scale dam breach experiments were conducted in Landao Stream, which is a tributary of Beigang River, length about 1,952 km and average altitude 1,200 meters. The total length of the experiment area is 280 m, and the average slope is 6.3°. Experiment I is a case of single dam and Experiment II is single dam with spur dike. In Experiment I, a seismic array of 20 stations was installed along the left and right banks of the river. In Experiment II, a seismic array of 12 stations was first deployed along the center of the river channel with station spacing distances of 10 m. Then, a seismic impact experiment was carried out to obtain the associated seismic parameters for seismic physical models. After the impact experiment, the seismometers were reinstalled on the left and right banks of river. For each experiment, the surveys of sediment grain size distribution and digital elevation model were conducted before and after experiment, which can provide information on erosion and deposit of river bed. Additionally, the water level, surface flow velocity, time-lapse photos, and temporal changes in beach shape were also monitored during experiment. With the available data of fluvial measurements, topographic changes in riverbeds, grain size survey, and seismic parameters, our study suggested that the riverine seismic signals can record the ground motions caused by water flow, sediment transport, and debris flow. Results of a series of time-frequency analysis presented the additional information about the erosion and sedimentation of river bed. Finally, our proposed mechanisms based on seismic physical models (e.g., turbulent flow, bedload saltation, and debris flow) will be discussed with the previous results of numerical simulation. Our results demonstrated that the riverine seismic signals of seismic array can effectively and immediately quantify downstream sedimentary erosion and deposition characteristics after the dam breaching.
A framework for cost-effective enrichment of water demand records at fine spatio-temporal scales
Authors: Kossieris Panagiotis , Tsoukalas Ioannis , Makropoulos Christos
Published: February 2023

Residential water demand is a key element of urban water systems, and hence its analysis, modelling and simulation is of paramount importance to feed modelling applications. During the last decades, the advent of smart metering technologies has released new streams of high-resolution water demand data, allowing the modelling of demand process at fine spatial (down to appliance level) and temporal (down to 1 sec) scales. However, high-resolution data (i.e., lower than 1 min) remains limited, while longer series at coarser resolution (e.g., 5 min or 15 min) do exist and are becoming increasingly more available, while the metering devices with such sampling capabilities have potential for a wider deployment in the near future. This work attempts to enrich the information at fine scales addressing the issue of data unavailability in a cost-effective way. Specifically, we present a novel framework that enables the generation of synthetic (yet statistically and stochastically consistent) water demand records at fine time scales, taking advantage of coarser-resolution measurements. The framework couples: a) lower-scale extrapolation methodologies to provide estimations of the essential statistics (i.e., probability of no demand and second-order properties) for model’s setup at fine scales, and b) stochastic disaggregation approaches for the generation of synthetic series that resamples the regime of the process at multiple temporal scales. The framework, and individual modules, are demonstrated in the generation of 1-min synthetic water demands at the household level, using 15 min data from the available smart meter.
Sill to dyke transition beneath a caldera: the competition between local stress and regional extension. Insights from analogue experiments applied to Campi Flegrei caldera, Italy.
Authors: Maccaferri Francesco , Gaete Roja Ayleen , Mantiloni Lorenzo
Published: February 2023

Unrests at calderas are usually characterized by surface uplift, which is often driven by the pressurization of a sill-like reservoir. If an unrest ends up with an eruption, the location and timing for the opening of the eruptive vent are difficult to predict. In fact, when a reservoir fails, a magmatic dyke nucleates and starts propagating towards the surface, following a direction that results from the interplay between magma pressure, local stress, and regional tectonic. Where and how a sill reservoir will fail is one of the most uncertain factors in such a pre-eruptive scenario. In order to study the transition between an inflating sill and a dyke intrusion, we developed an original analogue model set-up: We shaped the surface of a solidified gelatin block, reproducing a simplified topography of Campi Flegrei caldera (Italy). This provides our model with the local unloading stress due to the presence of the caldera. In addition, we introduced a variable horizontal extension by expanding the gelatin block in one direction, providing a regional extension. We placed a sill-type reservoir below the caldera, scaling its dimensions based on previous deformation studies at Campi Flegrei. In our experiments, the reservoir was progressively pressurized through the injection of air from the bottom of the gelatin block, simulating a process of shallow sill-reservoir activation by a deeper “feeder dyke”. Depending on the ratio between the local unloading stress and the regional extension, we observed two main behaviors for the nucleation of a shallow dyke: I) if the local stress dominates over the regional extension - when the sill overpressure reaches a critical value - we observed the lateral growth of the sill, followed by the progressive re-orientation of the intrusion towards vertical, thus forming a dike which fed a circumferential vent on the rim of the caldera; II) if the extension dominates, the sill-to-dyke nucleation still occurs at the edge of the sill, but with a vertical dyke opening in the direction of the regional extension (on the same plane as the feeder dyke). The intrusion grows towards the surface, leading to a radial fissure located at the edge of the caldera.Previous estimates for the stress state at Campi Flegrei caldera from Rivalta et al. (2019) would suggest that the most relevant mechanism for Campi Flegrei may be the one dominated by the local stress rather than the regional extension (type I).
FAIR & Open Material Samples: The IGSN ID
Authors: Edmunds Rorie
Published: February 2023

Material samples are a vital output of the scientific endeavour. They underpin research in the Earth, Space, and Environmental Sciences, and are a necessary component of ensuring the transparency and reproducibility of such research. While there has been a lot of discussion in recent years about the openness and FAIRness of data, code, methods, and so on, material samples have been much less under the spotlight.

The lack of focus on material samples is in part due to them being unique as a research output, in the sense that they are inherently physical and thus they are mostly transported and managed by human beings rather than machines; it is rather more straightforward to archive and share both information about an output—and the output itself—for something that is already a digital object. However, it is for this reason that materials samples must be made more FAIR and treated as first-class citizens of Open Science. To do this, one needs to connect the physical and digital worlds. IGSN IDs enable these connections to be made.

The IGSN ID is a globally unique and persistent identifier (PID) specifically for labelling material samples themselves (i.e., they are for neither images nor data about a sample). Functionally a Digital Object Identifier (DOI) registered under DataCite services, the IGSN ID can be applied to all types of material samples coming from any discipline. Not only can IGSN IDs be used to identify individual material samples that currently exist in a repository, museum, or otherwise, but they can also be registered

At the aggregate level for sample collections.

For the sites from which the samples are taken.

For ephemeral samples.

Importantly, in all cases, when registering an IGSN IDs, one must supply metadata in the DataCite Metadata Schema, as well as create landing pages that supply additional, disciplinary, user-focussed information about the collection, site, or (sub)sample. Hence, by registering a PID for a physical object, it is given a permanently resolvable URI to a findable and accessible digital footprint, and through the provision of rich metadata, enables its interoperability and reusability. Sharing of associated data is also possible within the metadata, and one may even include the potential for relocation of a sample itself for reuse.

This presentation will briefly introduce the IGSN ID and the partnership between DataCite and the IGSN e.V. to transfer the IGSN PID infrastructure under DataCite DOI services. It will mainly highlight practical use cases of IGSN IDs, including what is needed to include them in the sample workflow. It will also talk about efforts to better support IGSN IDs and sample metadata within the DataCite Metadata Schema.
Upscaling bacterial overland transport – a multi-parametric approach
Authors: Derx Julia , Linke Rita , Sommer Regina , Strauss Peter , Hykollari Alba , Faltejsek Alexander , Schijven Jack , Blaschke Alfred Paul , Kirschner Alexander , Farnleitner Andreas
Published: February 2023

Water contaminated with human and animal enteric pathogens puts public health at serious risk. All countries and regions of the world require highly robust and effective water management and treatment systems to guarantee safe water and protect public health. To this end, we need accurate predictions of the origin of pathogens , how they move through the environment and where they end up.This study is part of a four-year project and aims to develop new bacterial overland transport - BOT models to provide answers to the above questions. The project takes a holistic, quantitative approach to transfer BOT model parameters onto large scales. Small-scale precipitation experiments are conducted in the laboratory and larger-scale experiments are conducted using a rainfall simulation under real environmental conditions. The state-of-the-art combination of quantitative, microbiological, and molecular methods and parameters will provide the scientific basis for more accurate predictions of BOT, which eventually may be extended to viruses and protozoa in the future.
Progressing experimental methods for the hydrological characterization of structural soil substrates
Authors: Rath Sebastian , Zeiser Anna , Kumpan Monika , Strauß Peter , Weninger Thomas
Published: February 2023

Rising demand for functionality of green infrastructure in urban environments led to the development of combined systems for stormwater retention and infiltration together with urban trees. Frequently, a special type of substrate is used based on coarse gravel or cobbles (ca. 5 – 20 cm) as structure element ensuring load bearing capacity as well as stable pore volume and combine it with a fine growing substrate with a certain storage capacity for water and nutrients. These systems got different names in different parts of the world. They are called structural soils in the US and Singapore, Stockholm systems in Northern and parts of Central Europe, as well as sponge city substrates for urban trees in Austria. Despite progress in technical knowledge about Dos and Don´ts in the installation of structural soils and their stormwater retention functionality, there are no standard lab methods for their hydrological characterization by now.The main goal was to develop a lab method to determine the retention capacities at different matric potential states and the respective hydraulic conductivity of structural soil substrates. A major challenge therein is to handle the dimensions of the cobbles in lab conditions. For hydrological characterization, the multi-step-outflow method and the evaporation method were combined. The adopted changeable lab setup allows to determine the saturated hydraulic conductivity as well as the total pore volume at the beginning. Afterwards a ceramic pressure plate is used to perform the multistep-outflow method by applying certain negative pressures with a suction pump. In a third step the setup is changed to an evaporation method, which is used to determine the volumetric soil water content at more negative matric potentials.The first results provide a promising basis for further developments. For example, the available water capacity of structural soil substrates can be narrowed down to around 5 percent by volume, while the air capacity is around 21 percent by volume. This study represents a first step for developing appropriate methodology for a practicable hydrological characterization of structural soils. For the future, the experiment is intended to be extended by observations of wetting front characteristic and to be applied in standard procedures by a wide range of geotechnical or soil science laboratories.