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Climatic Vulnerability of El Mirador de Lambayeque Archaeological Complex (8th–11th Century AD): Morphometric Analyses of Digital Surface Models
No full textPublishedJCR Journa
UAV Multisensor Observation of Floating Plastic Debris: Experimental Results from Lake Calore
No full textThis study addresses the observation of floating plastic debris in freshwater environments using an Unmanned Aerial Vehicle (UAV) multi-sensor strategy. An experimental campaign is described where an heterogeneous plastic assemblage, namely a plastic target, and a naturally occurring leaf-litter mat are observed by a UAV platform in the Lake Calore (Avellino, Southern Italy) within the framework of the “multi-layEr approaCh to detect and analyze cOastal aggregation of MAcRo-plastic littEr” (ECOMARE) Italian Ministry of Research (MUR)-funded project. Three UAV platforms, equipped with optical, multispectral, and thermal sensors, are adopted, which overpass the two targets with the objective of analyzing the sensitivity of optical radiation to plastic and the possibility of discriminating the plastic target from the natural one. Georeferenced orthomosaics are generated across the visible, multispectral (Green, Red, Red Edge, Near-Infrared—NIR), and thermal bands. Two novel indices, the Plastic Detection Index (PDI) and the Heterogeneity Plastic Index (HPI), are proposed to discriminate between the detection of plastic litter and natural targets. The experimental results highlight that plastics exhibit heterogeneous spectral and thermal responses, whereas natural debris showed more homogeneous signatures. Green and Red bands outperform NIR for plastic detection under freshwater conditions, while thermal imagery reveals distinct emissivity variations among plastic items. This outcome is mainly explained by the strong NIR absorption of water, the wetting of plastic surfaces, and the lower sensitivity of the Mavic 3′s NIR sensor under high-irradiance conditions. The integration of optical, multispectral, and thermal data demonstrate the robustness of UAV-based approaches for distinguishing anthropogenic litter from natural materials. Overall, the findings underscore the potential of UAV-mounted remote sensing as a cost-effective and scalable tool for the high-resolution monitoring of plastic pollution over inland waters.PublishedJCR Journa
Applications of Fast Iterative Filtering in NMR Spectroscopy: Baseline Correction
No full textFast iterative filtering (FIF) is a recently introduced signal decomposition technique related to empirical mode decomposition (EMD), which has been developed for the analysis of non-stationary signals. When applied to the analysis of NMR data, FIF effectively partitions broad and narrow features by decomposing signals into intrinsic mode functions. In this work, we prove that FIF excels at separating baseline components from peaks, even in heavily distorted spectra. This capability is precious for processing spectra of paramagnetic compounds.PublishedJCR Journa
Sea level rise projections up to 2150 in the northern Mediterranean coasts
No full textVertical land movements (VLM) play a crucial role in affecting the sea level rise along the coasts. They need to be estimated and included in the analysis for more accurate Sea Level (SL) projections. Here we focus on the Mediterranean basin characterized by spatially variable rates of VLM that affect the future SL along the coasts. To estimate the VLM rates we used geodetic data from continuous global navigation satellite system stations with time series longer than 4.5 years in the 1996–2023 interval, belonging to Euro-Mediterranean networks and located within 5 km from the coast. Revised SL projections up to the year 2150 are provided at 265 points on a geographical grid and at the locations of 51 tide gauges of the Permanent Service for Mean Sea Level, by including the estimated VLM in the SL projections released by the Intergovernmental Panel on Climate Change (IPCC) in the AR6 Report. Results show that the IPCC projections underestimate future SL along the coasts of the Mediterranean Sea since the effects of tectonics and other local factors were not properly considered. Here we show that revised SL projections at 2100, when compared to the IPCC, show a maximum and minimum differences of 1094 ± 103 mm and
−773 ± 106 mm, respectively, with an average value that exceeds by about 80 mm that of the IPCC in the reference Shared Socio-economic Pathways and different global warming levels. Finally, the projections indicate that about 19.000 km2 of the considered Mediterranean coasts will be more exposed to risk of inundation for the next decades, leading to enhanced impacts on the environment, human activities and infrastructures, thus suggesting the need for concrete actions to support vulnerable populations to adapt to the expected SL rise and coastal hazards by the end of this century.Published014050OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
User Manual of GITpy: a Python-based tool for the Generalized Inversion Technique
No full textGITpy is an open-source object-oriented Python software that implements the Generalized Inversion
Technique (GIT) to isolate the source, propagation and site contributions to ground shaking in the spectral
domain (Fourier Amplitude Spectra, FAS). GITpy includes modules to perform both the non-parametric
spectral decomposition and to fit the resulting source spectra and spectral attenuation to standard
seismological models. Although the GIT is a well-established approach [Andrews 1986; Castro et al., 1990;
Boatwright et al., 1991; Oth et al., 2011; Bindi et al., 2020; Bindi et al., 2023a and 2023b], this tool offers the
opportunity to:
1) simplify the attenuation and source modeling process for the user through configuration files or
interactive procedures to test different models in a fast way;
2) choose between different levels of attenuation modeling complexity (geometrical spreading and
anelastic attenuation);
3) choose between different source spectrum modeling options such as applying a homogeneous or
heterogeneous crustal model or selecting the frequency range for the model fitting;
4) calculate apparent source spectra (and relative source parameters) through a specific module using
a procedure that allows the input FAS to be corrected for site amplification and non-parametric
attenuation obtained from the inversion, and then fit the source spectra as observed at the stations.
This is particularly useful for directivity studies. Furthermore, this module can be used
independently for a rapid estimation of source parameters in case of a strong event;
5) provide additional source parameters including the radiated energy, the apparent stress and the
radiation efficiency together with seismic moment, corner frequency and stress drop. The
additional parameters can be estimated for both the best-fit parametric source models and the
non-parametric GIT results.
Here we present the documentation to help Users in the execution of GITpy. We also provide an
example dataset (GITpy_db) to test the GITpy code and Jupyter Notebooks tutorials to guide the User
on how to run the four main python moduleSubmittedOST3 Vicino alla fagliaN/A or not JC
FEEDS: Validation of the Framework for Evaluation of Early Detection Systems
No full textMonitoring volcanic activity is a complex task, given the intricate nature of volcanic processes and the diverse eruptive styles exhibited by different volcanoes. Early Detection (ED) systems have emerged as indispensable tools for mitigating potential risks associated with volcanic eruptions. The effectiveness of these systems is contingent upon their ability to provide timely and accurate alerts, as false alarms or missed warnings can lead to economic repercussions and pose risks to infrastructure and human safety. Evaluating the reliability of the ED systems may be paramount not only for effective hazard mitigation but also for facilitating the implementation and optimization of an ED model. However, developing an ED model is a challenging and labor-intensive endeavor, also requiring a deep understanding of advanced techniques and a meticulous calibration of various parameters.
In response to these challenges, we present the Framework for Evaluation of Early Detection Systems (FEEDS). FEEDS is a comprehensive Python-based package designed to automatically assess the generalization capability of generic ED systems through cross-validation. The framework introduces a generic class representing the ED model identified solely through data, enabling a systematic assessment based on essential predictive parameters, including True Positive Rate, False Discovery Rate, prediction time, and Fraction of Time in Alarm, by performing a simulation.
To validate the effectiveness of FEEDS, we utilized tiltmeter and strainmeter data recorded at Stromboli volcano between 2007 and 2019. These datasets, managed by Istituto Nazionale di Geofisica e Vulcanologia and Università di Firenze, were employed to implement FEEDS with a customized model for the early detection of the paroxysmal activity affecting the volcano during the period of the study, demonstrating the practical applicability and reliability of this framework in real-world volcanic monitoring scenarios.
FEEDS may represent a valuable contribution to the ongoing efforts to enhance ED systems and their application in mitigating volcanic hazards. The development of a robust framework that automates the standard evaluation process not only streamlines system implementation but also reduces user efforts and establishes a common ground for assessing the reliability and performance of different ED models, contributing significantly to the advancement of volcanic monitoring capabilities.PublishedVienn
Design displacement for lifelines at fault crossings: the code-based approach for Europe
No full textThe earthquake-resistant design of lifelines, such as pipelines, tunnels and bridges, is based on the reliable representation and estimation of the seismic loading. In the case of lifeline–fault crossings, the design fault displacement is typically derived from estimates based on fault dimensions via empirical fault scaling relations for a given “design” scenario event. This approach comes with an unknown level of safety because the fault productivity and the actual distribution of earthquake events are essentially disregarded. To overcome this challenge, a simplified approach is proposed by statistically analyzing the outcome of probabilistic fault displacement hazard analyses (PFDHAs). A selection of faults from the 2020 European Fault-Source Model is used to build the logic tree and to set the range of parameters considered in the PFDHAs. The methodology allows the (mostly conservative) approximation of the fault displacement corresponding to any given return period based on readily available data, namely fault productivity, fault mechanism, fault length, and lifeline crossing location on the fault. The proposed methodology has been proposed and adopted as an informative Annex in prEN 1998-4:2022.Open access funding provided by HEAL-Link Greece. The current work has been partially undertaken in as part of the Horizon 2020 Seismology and Earthquake Engineering Research Infrastructure Alliance in Europe (SERA, Grant Agreement No. 730900). The first and the second author have received partial funding from the European Union’s Horizon 2020 research and innovation programme “METIS-Seismic Risk Assessment for Nuclear Safety” under Grant Agreement No. 945121 and also, the financial support provided by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “2nd Call for H.F.R.I. Research Projects to support Faculty Members & Researchers”, Project “TwinCity—Climate-Aware Risk and Resilience Assessment of Urban Areas under Multiple Environmental Stressors via Multi-Tiered Digital City Twinning” (Number: 2515) is gratefully acknowledged.Published2677–2720OST2 Deformazione e Hazard sismico e da maremotoJCR Journa
Direct observation of degassing during decompression of basaltic magma
No full textTransitions in eruptive style during volcanic eruptions strongly depend on how easily gas and magma decouple during ascent. Stronger gas-melt coupling favors highly explosive eruptions, whereas weaker coupling promotes lava fountaining and lava flows. The mechanisms producing these transitions are still poorly understood because of a lack of direct observations of bubble dynamics under natural magmatic conditions. Here, we combine x-ray radiography with a novel high-pressure/high-temperature apparatus to observe and quantify in real-time bubble growth and coalescence in basaltic magmas from 100 megapascals to surface. For low-viscosity magmas, bubbles coalesce and recover a spherical shape within 3 seconds, implying that, for lava fountaining activity, gas and melt remain coupled during the ascent up to the last hundred meters of the conduit. For higher-viscosity magmas, recovery times become longer, promoting connected bubble pathways. This apparatus opens frontiers in unraveling magmatic/volcanic processes, leading to improved hazard assessment and risk mitigation.Publishedeado2585OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Mass-change And Geosciences International Constellation (MAGIC) expected impact on science and applications
No full textThe joint ESA/NASA Mass-change And Geosciences International Constellation (MAGIC) has the objective to extend time-series from previous gravity missions, including an improvement of accuracy and spatio-temporal resolution. The long-term monitoring of Earth’s gravity field carries information on mass change induced by water cycle, climate change and mass transport processes between atmosphere, cryosphere, oceans and solid Earth. MAGIC will be composed of two satellite pairs flying in different orbit planes. The NASA/DLR-led first pair (P1) is expected to be in a near-polar orbit around 500 km of altitude; while the second ESA-led pair (P2) is expected to be in an inclined orbit of 65°–70° at approximately 400 km altitude. The ESA-led pair P2 Next Generation Gravity Mission shall be launched after P1 in a staggered manner to form the MAGIC constellation. The addition of an inclined pair shall lead to reduction of temporal aliasing effects and consequently of reliance on de-aliasing models and post-processing. The main novelty of the MAGIC constellation is the delivery of mass-change products at higher spatial resolution, temporal (i.e. subweekly) resolution, shorter latency and higher accuracy than the Gravity Recovery and Climate Experiment (GRACE) and Gravity Recovery and Climate Experiment Follow-On (GRACE-FO). This will pave the way to new science applications and operational services. In this paper, an overview of various fields of science and service applications for hydrology, cryosphere, oceanography, solid Earth, climate change and geodesy is provided. These thematic fields and newly enabled applications and services were analysed in the frame of the initial ESA Science Support activities for MAGIC. The analyses of MAGIC scenarios for different application areas in the field of geosciences confirmed that the double-pair configuration will significantly enlarge the number of observable mass-change phenomena by resolving smaller spatial scales with an uncertainty that satisfies evolved user requirements expressed by international bodies such as IUGG. The required uncertainty levels of dedicated thematic fields met by MAGIC unfiltered Level-2 products will benefit hydrological applications by recovering more than 90 per cent of the major river basins worldwide at 260 km spatial resolution, cryosphere applications by enabling mass change signal separation in the interior of Greenland from those in the coastal zones and by resolving small-scale mass variability in challenging regions such as the Antarctic Peninsula, oceanography applications by monitoring meridional overturning circulation changes on timescales of years and decades, climate applications by detecting amplitude and phase changes of Terrestrial Water Storage after 30 yr in 64 and 56 per cent of the global land areas and solid Earth applications by lowering the Earthquake detection threshold from magnitude 8.8 to magnitude 7.4 with spatial resolution increased to 333 km.Published1288–1308JCR Journa
A statistical framework for detection of b-value anomalies in Italy
No full textThis study presents a new robust statistical framework, in which to measure relative differences, or deviations from a hypothetical reference value, of Gutenberg-Richter b-value. Moreover, it applies this method to recent seismicity in Italy, to find possible changes of earthquake magnitude distribution in time and space. The method uses bootstrap techniques, which have no prior assumptions about the distribution of data, keeping their basic features. Excluding Central Italy, no significative b-value variation is found, revealing that the frequency-magnitude distribution exponent is substantially stable or that data are not able to reveal hidden variations. Considering the small size of examined magnitude samples, we cannot definitively decide if the higher b-values in Central Italy, consistently founded by all applied tests, have a physical origin or result from a statistical bias. In any case, they indicate short-lived excursions which have a temporary nature and, therefore, cannot be associated solely to spatial variations in tectonic framework. Both the methodological issues and the results of the application to seismicity in Italy show that a correct assessing of b-value changes requests appropriate statistics, that accurately quantify the low accuracy and precision of b-value estimation for small magnitude samples.Published729–740OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impattoJCR Journa