ALBERT

Description: Third-generation gravitational wave observatories will extend the lower frequency limit of the observation band toward 2 Hz, where new sources of gravitational waves, in particular intermediate-mass black holes (IMBH), will be detected. In this frequency region, seismic noise will play an important role, mainly through the so-called Newtonian noise, i.e., the gravity-mediated coupling between ground motion and test mass displacements. The signal lifetime of such sources in the detector is of the order of tens of seconds. In order to determine whether a candidate site to host the Einstein Telescope observatory is particularly suitable to observe such sources, it is necessary to estimate the probability distributions that, in the characteristic time scale of the signal, the sensitivity of the detector is not perturbed by Newtonian noise. In this paper, a first analysis is presented, focused on the Sos Enattos site (Sardinia, Italy), a candidate to host the Einstein Telescope. Starting from a long data set of seismic noise, this distribution is evaluated considering both the presently designed triangular ET configuration and also the classical ”L” configuration.

Description: Published

Description: 511

Description: 2IT. Laboratori analitici e sperimentali

Description: JCR Journal

Description: By 2030, the success of Ocean Decade Challenge No.1 ‘Understand and Beat Marine Pollution’ will be demonstrated by the generation of scientifically sound data enabling a holistic understanding of the extent and impact of pollution across the land-ocean continuum, thereby supporting the achievement of a cleaner and healthier ocean where all ecosystems and their inhabitants thrive free from the impacts of marine pollution, allowing for their full functioning and service provision. This success will be based on completion of a comprehensive review of all available evidence about marine pollution, including an analysis of data gaps and the development and implementation of strategies for filling those gaps, as well as a comprehensive analysis of solutions for addressing and preventing the negative effects of marine pollution. Achieving this success will require knitting together existing and new data sets using AI and other technologies, identifying priority pollutants and areas for action, and providing globally consistent monitoring, data collection, storage and sharing protocols. Success will further be demonstrated through the establishment of new connections and partnerships among users across the public - private spectrum that lead to the funding, development and implementation of new technologies and projects aimed at monitoring, controlling, reducing, and/or mitigating marine pollution from any source, including the creation and sustainability of a global network of strategically positioned sentinel stations and regional laboratory hubs for sustained, long-term monitoring of marine pollution. Success will include fulfilment of the following critical knowledge gaps: • a comprehensive and holistic understanding of the impacts of priority pollutants (e.g., pollutants found or expected to emerge in high concentrations, or with high toxicity, or with significant adverse effects on biota or human health) across the land to ocean continuum; • a better understanding of the sources, sinks, fate and impacts of all pollutants, including the pollutants of emerging concern; • improved knowledge on the distribution and impacts of marine pollution, particularly in the Global South and deep ocean waters, which currently represent the largest geographical gaps. and the following priority datasets gaps: • long-term time series of marine pollutants; • baseline and toxicity data of pollutants across the land-ocean continuum; • data on the impacts of the co-occurrence of multiple pollutants; • data on the effects of climate change on the toxicity, bioavailability and impacts of multiple co-existent pollutants. • It will include development of: • a global network of strategically positioned sentinel stations for continuous, long-term monitoring; • cost-effective, real-time monitoring systems and technologies for tracking pollutant sources, distribution, and transfers across the land-ocean continuum; • a global network of regional laboratory hubs focused on generating high-quality data, promoting capacity building and facilitating technology transfer; • training programs on harmonized protocols for the acquisition, reporting and recording of quality-controlled data on marine pollution; • environmentally robust new technologies and processes for the control and mitigation of marine pollution.

Description: Published

Description: Refereed

Description: By 2030, successful achievement of Ocean Decade Challenge No. 6 will require demonstrating substantial advancements within the global community towards enhancing their resilience to coastal and ocean hazards. This includes implementing two crucial elements: (1) establishing comprehensive 'people-centered' early warning systems capable of addressing multiple hazards, and (2) devising adaptation strategies that specifically target risks associated with the ocean, including those linked to climate change. These endeavours will play a pivotal role in guiding sustainable practices in ocean planning. Success will also hinge on addressing critical gaps in scientific understanding and knowledge across important components such as risk assessment and risk reduction, in addition to putting in place robust institutional mechanisms for implanting novel solutions that contribute to coastal resilience. Some key elements to be addressed in this context include: (i) gathering and generating observational and modelling datasets relevant to risk assessment, including downscaled climate scenarios for coastal regions, within robust data-sharing frameworks; (ii) promoting interdisciplinary and international research and innovation to tackle challenges comprehensively, with a focus on methodologies like Digital Twin approaches; (iii) improving standards for risk communication at both national and international levels; (iv) fostering partnerships at various scales involving local communities, public and private disaster risk reduction entities, governmental bodies, and academic institutions; (v) building capacity in research and communication to cultivate a shared understanding of coastal resilience strategies; and (vi) enhancing resilient infrastructure and promoting sustainable resource management along coastlines. It is imperative to establish partnerships with existing international UN programs dedicated to disaster risk reduction and coastal resilience. Strengthening connections with UN Decade Actions through Decade Coordination Offices and Decade Collaboration Centers is of utmost importance for effective coordination and collaboration. Based on the above strategic ambition it is also suggested that the formulation of the Ocean Decade Challenge could be modified as follows: Increase community resilience to ocean and coastal risks

Description: Published

Description: Refereed

Description: 〈jats:p〉Persistent cold temperatures, a paucity of nutrients, freeze-thaw cycles, and the strongly seasonal light regime make Antarctica one of Earth’s least hospitable surface environments for complex life. Cyanobacteria, however, are well-adapted to such conditions and are often the dominant primary producers in Antarctic inland water environments. In particular, the network of meltwater ponds on the ‘dirty ice’ of the McMurdo Ice Shelf is an ecosystem with extensive cyanobacteria-dominated microbial mat accumulations. This study investigated intact polar lipids (IPLs), heterocyte glycolipids (HGs), and bacteriohopanepolyols (BHPs) in combination with 16S and 18S rRNA gene diversity in microbial mats of twelve ponds in this unique polar ecosystem. To constrain the effects of nutrient availability, temperature and freeze-thaw cycles on the lipid membrane composition, lipids were compared to stromatolite-forming cyanobacterial mats from ice-covered lakes in the McMurdo Dry Valleys as well as from (sub)tropical regions and hot springs. The 16S rRNA gene compositions of the McMurdo Ice Shelf mats confirm the dominance of Cyanobacteria and Proteobacteria while the 18S rRNA gene composition indicates the presence of Ochrophyta, Chlorophyta, Ciliophora, and other microfauna. IPL analyses revealed a predominantly bacterial community in the meltwater ponds, with archaeal lipids being barely detectable. IPLs are dominated by glycolipids and phospholipids, followed by aminolipids. The high abundance of sugar-bound lipids accords with a predominance of cyanobacterial primary producers. The phosphate-limited samples from the (sub)tropical, hot spring, and Lake Vanda sites revealed a higher abundance of aminolipids compared to those of the nitrogen-limited meltwater ponds, affirming the direct affects that N and P availability have on IPL compositions. The high abundance of polyunsaturated IPLs in the Antarctic microbial mats suggests that these lipids provide an important mechanism to maintain membrane fluidity in cold environments. High abundances of HG keto-ols and HG keto-diols, produced by heterocytous cyanobacteria, further support these findings and reveal a unique distribution compared to those from warmer climates.〈/jats:p〉

Description: In this paper, we propose the use of advanced and flexible statistical models to describe the spatial displacement of earthquake data. The paper aims to account for the external geological information in the description of complex seismic point processes, through the estimation of models with space varying parameters. A local version of the Log-Gaussian Cox processes (LGCP) is introduced and applied for the first time, exploiting the inferential tools in Baddeley (Spat Stat 22:261–295, 2017), estimating the model by the local Palm likelihood. We provide methods and approaches accounting for the interaction among points, typically described by LGCP models through the estimation of the covariance parameters of the Gaussian Random Field, that in this local version are allowed to vary in space, providing a more realistic description of the clustering feature of seismic events. Furthermore, we contribute to the framework of diagnostics, outlining suitable methods for the local context and proposing a new step-wise approach addressing the particular case of multiple covariates. Overall, we show that local models provide good inferential results and could serve as the basis for future spatio-temporal local model developments, peculiar for the description of the complex seismic phenomenon.

Description: Published

Description: 633–671

Description: 3T. Fisica dei terremoti e Sorgente Sismica

Description: JCR Journal

Description: In this paper, we propose a novel picking algorithm for the automatic P- and S-waves onset time determination. Our algorithm is based on the variance piecewise constant models of the earthquake waveforms. The effectiveness and robustness of our picking algorithm are tested both on synthetic seismograms and real data. We simulate seismic events with different magnitudes (between 2 and 5) recorded at different epicentral distances (between 10 and 250 km). For the application to real data, we analyse waveforms from the seismic sequence of L’Aquila (Italy), in 2009. The obtained results are compared with those obtained by the application of the classic STA/LTA picking algorithm. Although the two algorithms lead to similar results in the simulated scenarios, the proposed algorithm results in greater flexibility and automation capacity, as shown in the real data analysis. Indeed, our proposed algorithm does not require testing and optimization phases, resulting potentially very useful in earthquakes routine analysis for novel seismic networks or in regions whose earthquakes characteristics are unknown.

Description: Published

Description: 2101-2113

Description: 8T. Sismologia in tempo reale e Early Warning Sismico e da Tsunami

Description: JCR Journal

Description: Stromboli (Italy) is a basaltic volcano characterized by persistent, mild strombolian activity, occasionally interrupted by lava effusion and more violent explosive events, named major explosions and paroxysms depending on their intensity and magnitude. The normal activity is fed by a shallow and degassed highly porphyritic (HP) shoshonitic basalt carrying about 50 vol.% crystals settled in a shoshonitic glassy matrix ( K2O 〉 3.8 wt.%). The more energetic explosions erupt a deep, volatile-rich, low-porphyritic (LP) magma with 〈 10 vol.% crystals in a shoshonitic basaltic glassy matrix ( K2O 〈 2.4 wt.%). Products with intermediate glass composition are also found in the more violent explosive events. In this study, we present a new data set of major and trace element contents in matrix glasses and minerals performed in products from different types of explosive activity that occurred at Stromboli between 1998 and 2020. This large data set is used to put constraints on the evolution and architecture of the intermediate plumbing system, where the transformation from LP to HP occurs. Results indicate that, compared to paroxysms, the glassy matrices of the LP pumices from major explosions are richer in incompatible trace elements (and K2O wt.%) due to 〈 15 wt.% fractionation of clinopyroxene and olivine. This points to a chemical zoning of the deep reservoir and suggests that major explosions are fed by magmas residing in its upper part. Among the major explosions, the homogeneous intermediate glasses in the products from the 19 July 2020 event originate from the interplay of mixing and crystal fractionation processes. The crystallization of euhedral microphenocrysts of An-rich plagioclase suggests that batches of magma can pond and crystallize for few days (〈 11) at the base of the intermediate zone of the plumbing system, at pressure coinciding with the entering of plagioclase into the system (〈 100 MPa). As a relevant point for understanding the pre- and syn-eruptive magma dynamics, data indicate a positive correlation between the magnitude of the explosions and the depth of the supply magma.

Description: Published

Description: 96

Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici

Description: JCR Journal

Description: The Pliocene Epoch (∼5.3-2.6 million years ago, Ma) was characterized by a warmer than present climate with smaller Northern Hemisphere ice sheets, and offers an example of a climate system in long-term equilibrium with current or predicted near-future atmospheric CO2 concentrations (pCO2). A long-term trend of ice-sheet expansion led to more pronounced glacial (cold) stages by the end of the Pliocene (∼2.6 Ma), known as the “intensification of Northern Hemisphere Glaciation” (iNHG). We assessed the spatial and temporal variability of ocean temperatures and ice-volume indicators through the late Pliocene and early Pleistocene (from 3.3 to 2.4 Ma) to determine the character of this climate transition. We identified asynchronous shifts in long-term means and the pacing and amplitude of shorter-term climate variability, between regions and between climate proxies. Early changes in Antarctic glaciation and Southern Hemisphere ocean properties occurred even during the mid-Piacenzian warm period (∼3.264-3.025 Ma) which has been used as an analogue for future warming. Increased climate variability subsequently developed alongside signatures of larger Northern Hemisphere ice sheets (iNHG). Yet, some regions of the ocean felt no impact of iNHG, particularly in lower latitudes. Our analysis has demonstrated the complex, non-uniform and globally asynchronous nature of climate changes associated with the iNHG. Shifting ocean gateways and ocean circulation changes may have pre-conditioned the later evolution of ice sheets with falling atmospheric pCO2. Further development of high-resolution, multi-proxy reconstructions of climate is required so that the full potential of the rich and detailed geological records can be realized.

Description: The management of multiple hazards simultaneously impacting on a territory is a challenge for effective risk mitigation. This is particularly true on active volcanoes like Mt. Etna, characterized by effusive and explosive eruptions, often coupled with an intense seismic activity. This work aims at presenting the approach of the PANACEA project on the treatment of multi-hazards in terms of risk, which requires a common definition of the exposed elements and their vulnerability. Another aspect emerging from the recent and historical volcanic crises at Etna, is the occurrence of cascading effects and the problem of assessing their short-term interactions. Here we present a risk model taking into account a set of sequences of hazardous events which may result from a volcano unrest to possible impacts to some infrastructural elements. The outcomes of the project are intended to be a significant step towards a more comprehensive resilience to volcanic disasters, leading to a more safe society.

Description: Published

Description: 37-40

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: Growth rates and other biomass traits of phytoplankton are strongly affected by temperature. We hypothesized that resulting phenotypes originate from deviating temperature sensitivities of underlying physiological processes. We used membrane-inlet mass spectrometry to assess photosynthetic and respiratory O2 and CO2 fluxes in response to abrupt temperature changes as well as after acclimation periods in the diatom Phaeodactylum tricornutum. Abrupt temperature changes caused immediate over- or undershoots in most physiological processes, that is, photosynthetic oxygen release ((Figure presented.)), photosynthetic carbon uptake ((Figure presented.)), and respiratory oxygen release ((Figure presented.)). Over acclimation timescales, cells were, however, able to re-adjust their physiology and revert to phenotypic ‘sweet spots’. Respiratory CO2 release ((Figure presented.)) was generally inhibited under high temperature and stimulated under low-temperature settings, on abrupt as well as acclimation timescales. Such behavior may help mitochondria to stabilize plastidial ATP : NADPH ratios and thus maximize photosynthetic carbon assimilation.