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An Expedited Procedure to Highlight Rapid Recharge Processes by Means of Nitrate Pollution Dynamics in the Northern Italy Plain
No full textIn recent decades, increasing anthropogenic pressure and climate change have made
the protection and sustainable management of groundwater resources essential. In this
context, the identification of aquifer recharge zones, especially those characterized by rapid
groundwater flow and high vulnerability to surface pollution sources, becomes a priority
for the protection of underground resources. In the Po Plain (northern Italy), based on
the lithological, geometric, hydraulic, and hydrodynamic characteristics of the aquifers,
the recharge areas are mainly located in the alluvial fans of the Alpine and Apennine
foothills. Due to the high hydraulic conductivity of the aquifer, the shallow depth of
the water table and the agricultural activities, groundwater resources are vulnerable to
nitrate (NO3
−) contamination. Given this background, the present study introduces a novel
methodological approach based on the geochemical signature of groundwater, indicated
by the presence of bicarbonate (HCO3
−) and NO3
− ions, aimed at identifying aquifer
recharge areas. Specifically, by analyzing time series of NO3
− and HCO3
− concentrations
for the period 2012–2023, and applying criteria of an HCO3
−/NO3
− ratio < 10 and NO3
−
> 30 mg/L, it was possible to identify areas where aquifer recharge processes are clearly
evident. These recharge processes are rapid, as confirmed by the hydraulic gradient,
the high hydraulic conductivity of the aquifers, and further supported by the isotopic
composition of groundwater, especially tritium concentrations. Furthermore, due to the
hydrogeological characteristics of the surveyed region, which resemble those of alluvial
basins in close proximity to mountain ranges, the methodology and findings of this study
can be used as an unconventional and expedited method for similar research conducted
globally, offering hope for the future of groundwater research.PublishedJCR Journa
An experiment on earthquake size distribution estimations reveals unexpected large epistemic uncertainty across methods
No full textThe earthquake size distribution is well described by the Gutenberg Richter Law, controlled by
the b-value parameter. In recent decades, a great variety of methods for estimating the b-value
have been proposed by the scientific community, despite the simplicity of this relationship.
All these methods underlie the different views of individual modellers and, therefore, often
generate inconsistent results. In thisstudy, we perform a seismological experiment in which we
compare different, commonly adopted, methodologies, to estimate the completeness magnitude
and the b-value, for seismicity in Central Italy. The intermethod differences are on average
equal to 0.4 and 0.3, for Mc and b, respectively, but reach much larger values, especially during
more intense seismic activity. Thisshowsthat epistemic uncertainty in the b-value plays a more
crucial role than intramethod uncertainties, opening new perspectives in the interpretation of
discrepant, single studies.PublishedJCR Journa
Boosting total electron content forecasting based on deep learning toward an operational service
No full textWe present a prediction model based on deep learning able to forecast ionospheric Total Electron Content at global level 24 h in advance. It has been conceived to operate under different space weather scenarios and in an operational framework. Three different deep learning (DL) techniques have been compared: Long Short Term Memory (LSTM), Gated Recurrent Units (GRU) and Convolutional Neural Networks (CNN). The modelling approach inherits by and extends what has been proposed by Cesaroni and co-authors (2020a). Specifically, the machine learning-based approach here reported is conceived to improve the first step of Cesaroni et al. (2020a), in which TEC is forecasted on 18 selected grid points of Global Ionospheric Maps (GIMs) using the geomagnetic global index Kp index as the external input. CNN models provide better predictive capabilities than LSTM and GRU, and it has more robust behaviour under different space weather conditions. We also show how all the proposed models outperform the two naive models: the so-called "frozen ionosphere" or recurrence model and a 27 days averaged model. The novelty of our approach is the operational capability based on an incremental learning method to prevent the aging of the trained models by updating the weights with little computational effort adding new information immediately after the 24-h forecasting. The improvement changed from RMSE of ~6.5 TECu to ~2.5 TECu.We also discuss limitations and the use of other space weather inputs (e.g. solar proxies, other geomagnetic indexes, etc) and the use of complementary data science techniques (e.g. data preparation, hyperparameter tuning, better data resolution, etc.) to enhance the forecasting in future works.PublishedJCR Journa
Cause‐and‐Effect Relationships Between Sea Surface Temperature Changes in Different Regions During the Past 4.5 Million Years
No full textPublishedOSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
Numerical simulations reveal the dynamics of the most intense eruption of Hunga Tonga in January 2022
No full textA violent undersea explosive eruption occurred at Hunga Tonga-Hunga Ha'apai volcano on 15 January 2022, generating an eruption cloud more intense than any previously observed. We performed numerical simulations of eruption cloud dynamics using a 3D fluid-dynamic model and an ensemble-based tephra dispersal inversion model to reconstruct the eruption's climactic phase and compare it with available observations. Our results reveal that during this phase, 190-1500 Tg of seawater interacted with magma, producing a mass flow rate of the eruptive magmatic mixture of 3.2-6.3 × 10⁹ kg s −1 , which is several times more intense than the 1991 Pinatubo eruption. Moreover, we show that the eruption cloud, which injected approximately 1 Tg of volcanic ash and 0.1 Tg of seawater into the mesosphere, was in a state of thermal disequilibrium with the surrounding environment. The eruption injected 0.3-11 Tg sulfur dioxide into the atmosphere. These results suggest that a substantial amount of magmatic material, water vapor, and sulfur dioxide was injected into the stratosphere and mesosphere during this eruption, which could have a significant impact on the global climate several years after the eruption. Our work also shows the importance of high-resolution simulations in capturing the complex dynamics of eruption plumes generated by undersea volcanic eruptions, leading to more accurate predictions of eruption impacts.PublishedOSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Anthropogenic climate change has increased severity of mid-latitude storms and impacted airport operations
No full textPublishedOSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
Primo ritrovamento di rutilo nei proietti del Monte Somma
No full textIn a rather particular project of Monte Somma coming from the well-known quarries of San Vito (Ercolano), several minerals were found, one of which was quite interesting: rutile. The sample came from a batch of samples received by one of us (L.C.) from the collector Professor Achille Panunzi of Portici.PublishedN/A or not JC
Modeling the Magnetic Connection from Earth to Solar Corona during the May 11 Geomagnetic Superstorm
No full textPublishedOSA3: Climatologia e meteorologia spazialeJCR Journa
Modeling and simulation of volcanic mass movements and induced tsunamis at Stromboli volcano (Aeolian archipelago, Tyrrhenian sea, Italy)
No full textPublishedOSV1: Verso la previsione dei fenomeni vulcanici pericolosiJCR Journa
Subsurface characterization of crystalline rocks at the Einstein Telescope candidate site (Italy): Insights from seismic tomography, geoelectrical and morphostructural analyses
No full textThe Einstein Telescope (ET) will be the first European underground observatory of gravitational waves. The observatory’s interferometric detectors will be housed in a large underground infrastructure, which necessitates a stable and quiet geological context. We present the results of a geognostic campaign conducted for the Italian candidate site in Sardinia, during which two ~270 m-deep boreholes were drilled in granites and orthogneiss at two sites that are possible locations of the ET infrastructure. We acquired high-resolution, dense seismic and electrical resistivity tomography (ERT) profiles to complement borehole data, constraining the thickness of the weathered layer and characterizing the rock properties in terms of intact versus fractured zones down to depths of 100–240 m. At depths >50 m, we observed high P-wave velocity (Vp ~ 5000–5500 m/s, while very high Vp (~6000 m/s) paired with very high resistivity (ρ > 1000 Ωm) was found at depths of 150–200 m, suggesting unfractured or weakly fractured rocks consistent with borehole logs and literature data on geophysical surveys on crystalline rocks. We recognized a couple of sub-vertical low-Vp (~4250–4500 m/s) and low-resistivity anomalies (ρ < 500 Ωm), up to ~15–35 m-wide, suggesting the occurrence of fracture zones with groundwater, matching the intersection with fault zones mapped at the surface. Comparison with co-located resistivity sections, downhole seismic surveys, well logs, and field-based structural and morphostructural analyses allowed us to attribute these anomalies to fault zones ~0.3–0.5 km-long that belong to an immature fault network with shallow water circulation. This methodological approach highlights the utility of tomographic techniques combined with structural investigations and represents a guideline that can be applied in similar contexts characterized by poorly fractured crystalline rocks.PublishedJCR Journa