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Participatory downscaling of global SSP–RCP scenarios to local fisheries social–ecological systems
No full textInternational audiencePolicymakers and managers need projections of the trajectories of change in human societies and natural ecosystems to plan actions to address the potential consequences of global change. There are many projections at the global scale, but these need to be downscaled to local marine social–ecological systems to plan targeted interventions. We aimed to provide policy-relevant projections of the consequences of climate change and socio-economic orientations for the fisheries of the French North Sea and the Mediterranean. Our approach consisted of a downscaling of global scenarios of IPCC Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs) for the 2100 horizon. We engaged with fisheries managers, policymakers, scientific experts, and NGOs, and co-constructed four contrasting scenarios through interdisciplinary participatory workshops. Our approach ensured strong anchoring in regional, national, and local contexts and provided references to fisheries scenarios. We then conducted a novel comparative analysis of SSP–RCP scenario narratives from different local marine social–ecological systems in the same country. Across all scenarios, 83% of the themes highlighted by the stakeholders were common between the two social–ecological systems. However, within the themes, at a more detailed level, only 30% of the narrative elements were mentioned in both systems, reflecting the specificity and richness of these downscaled scenarios and their relevance to local management. We also integrated disruptive changes and emotional aspects by conducting a novel standardized emotion analysis using an artificial intelligence language model. Overall, these downscaled scenarios identified pathways to be avoided, as well as potential actions for transformative change, mitigation, and adaptation to global change at the local scale. Our protocol allowed us to address some criticisms of SSP–RCP scenarios by helping to bridge science–policy gaps and to focus more on human–nature relationships
ALMA-IMF: XVII. Census and lifetime of high-mass prestellar cores in 14 massive protoclusters
No full textInternational audienceContext. High-mass prestellar cores are extremely rare. Until recently, the search for such objects has been hampered by small sample sizes, leading to large ambiguities in their lifetimes and hence the conditions in the cores in which high-mass stars (≳8 M⊙) form. Aims. Here we leverage the large sample (~580 cores) detected in the ALMA-IMF survey to identify both protostellar and prestellar cores to estimate their relative lifetimes. Methods. We used CO and SiO outflows to identify protostellar cores. We present a new automated method based on aperture line emission and background subtraction to systematically detect outflows associated with each of the 141 most massive cores. Massive cores that are not driving an outflow in either tracer are identified as prestellar. After careful scrutiny of the sample, we derived statistical lifetime estimates for the prestellar phase. Results. Our automated method allows the efficient detection of CO and SiO outflows and has a performance efficiency similar to that of more cumbersome classical techniques. We identified 30 likely prestellar cores with M≳ 8 M⊙, of which 12 have core masses M≳ 16 M⊙. The latter group contains the best candidates for high-mass star precursors. Moreover, most of these 12 high-mass prestellar cores are located inside the crowded central regions of the protoclusters, where most high-mass stars are expected to form. Using the relative ratios of prestellar to protostellar cores, and assuming a high-mass protostellar lifetime of 300 kyr, we derive a prestellar core lifetime of 120 kyr to 240 kyr for cores with masses 8 M⊙ < M < 16 M⊙. For 30 M⊙ < M < 55 M⊙, the lifetimes range from 50 kyr to 100 kyr. The spread in timescales reflects different assumptions for scenarios for the mass reservoir evolution. These timescales are remarkably long compared to the 4 kyr to 15 kyr free-fall time of the cores. Hence, we suggest that high-mass cores live ~10 to 30 free-fall times, with a tentative trend of a slight decrease with core mass. Such high ratios suggest that the collapse of massive cores is slowed down by non-thermal support of turbulent, magnetic or rotational origin at or below the observed scale
Quantitative Security Metrics: Assessment of Cyberattack Scenarios for Cyber-Physical Systems
No full textInternational audienceCyber-Physical Systems (CPS) are digitized infrastructures controlling physical processes. To improve their dependability, we propose in this paper CYBERSIM, a framework to jointly automate safety and cybersecurity risk assessments for CPS in a common tool by means of generating cyberattack scenarios compromising system safety. However, due to the state space size of these complex systems, the sequence generation is subject to combinatorial explosion leading to an unmanageable number of attack scenarios. We develop in CYBERSIM a flexible and multi-metrics cost function which enables us to filter out quantitatively sequences of lesser importance and concentrate analysts efforts on the system's most critical weaknesses. This cost model using CVSS scores computed for MITRE EMB3D threats has been applied to an automotive case study in order to prove its applicability and effectiveness in an industrial contex
"La délégation d’écriture en création contemporaine. État des lieux et perspectives"
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GI 725A b: A potential super-Earth detected with SOPHIE and SPIRou in an M dwarf binary system at 3.5 pc
No full textInternational audienceWe report the discovery of a super-Earth candidate orbiting the nearby mid-M dwarf Gl 725A using the radial velocity (RV) method. The planetary signal has been independently identified using high-precision RVs from the SOPHIE and SPIRou spectrographs, in the optical and near-infrared (NIR) domains, respectively. We modelled the stellar activity signal jointly with the planet using two Gaussian processes, one for each instrument to account for the chromaticity of the stellar activity and instrumental systematics, along with a Keplerian model. The signal was significantly detected with a RV semi-amplitude of 1.67 ± 0.20 m/s. The planet Gl725A b is found to be in an orbit compatible with circular with a period of 11.2201 ± 0.0051 days. We analysed 27 sectors of TESS photometry, for which no transit event was found. We determined a minimum mass of Mp sin i = 2.78 ± 0.35 M⊕, which places the planet in the super-Earth regime. Using mass-radius relationships, we predict the planetary radius to be between 1.2 and 2.0 R⊕. The proximity of Gl 725A (at only 3.5 pc) makes this new exoplanet one of the closest to Earth and joins the group of S-type low-mass planets in short orbits (P < 15 days) around close M dwarfs
Review of Multiport Energy Router Structures in the Specific Context of Wind Power Generation Systems
No full textInternational audienceThe recent trend of using a multiport machine as an energy router has appeared and become an attractive solution in drive-included applications like wind turbines. This paper provides a review of multiport converters and machines, their integration in a wind generation system is evaluated. Then, a novel energy router structure based on the highly coupled multiport machine is proposed. The energy router enables energy storage integration in the wind turbine generation system. A power control scheme is implemented, and simulation results show that the multiport machine energy router can achieve similar power regulations of a standard DC coupled energy router
Observations of the temporal evolution of Saturn’s stratosphere following the Great Storm of 2010–2011: I. Temporal evolution of the water abundance in Saturn’s hot vortex of 2011–2013
No full textInternational audienceContext. Water vapour is delivered to Saturn’s stratosphere by Enceladus’ plumes and subsequent diffusion in the planet system. It is expected to condense into a haze in the middle stratosphere. The hot stratospheric vortex (the ‘beacon’) that formed as an aftermath of Saturn’s Great Storm of 2010 significantly altered the temperature, composition, and circulation in Saturn’s northern stratosphere. Previous photochemical models suggested haze sublimation and vertical winds as processes likely to increase the water vapour column density in the beacon.Aims. We aim to quantify the temporal evolution of stratospheric water vapour in the beacon during the storm.Methods. We mapped Saturn at 66.44 and 67.09 μm on seven occasions from July 2011 to February 2013 with the PACS instrument of the Herschel Space Observatory (Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA). The observations probe the millibar levels, at which the water condensation region was altered by the warmer temperatures in the beacon. Using radiative transfer modelling, we tested several empirical and physically based models to constrain the cause of the enhanced water emission found in the beacon.Results. The observations show an increased emission in the beacon that cannot be reproduced only accounting for the warmer temperatures reported in the beacon. An additional source of water vapour is thus needed. We find a factor (7.5±1.6) increase in the water column in the beacon compared to pre-storm conditions using empirical models. Combining our results with a cloud formation model for July 2011, we evaluate the sublimation contribution to 45–85% of the extra column derived from the water emission increase in the beacon.Conclusions. The observations confirm that the storm conditions enhanced the water abundance at the millibar levels because of haze sublimation and vertical winds in the beacon. Future work on the haze temporal evolution during the storm will help to better constrain the sublimation contribution over time
Non-thermal energy release in the post-impulsive phase of the May 9, 2021 event
No full textInternational audienceContext. In the standard model of solar flares, a magnetic flux rope erupts and gets ejected from the Sun. The current sheets that form in its wake are the seat of magnetic reconnection, which is thought to power energy release throughout the long-lasting decay phase of the thermal X-ray emission. This model has been broadly tested with plasma diagnostics at soft X-ray, EUV, and Hα wavelengths.Aims. The primary aim of the present investigation is to shed light on the acceleration of non-thermal electrons in the post-impulsive phase through hard X-ray (HXR) radiation and radio spectroscopic imaging at decimeter-to-meter wavelengths. We focus our study on the case of a C4.0 class flare on May 9, 2021.Methods. This event was fully observed by multiple instruments from three different vantage points in space. We analyzed the spectrum and the source configuration of X-ray emission with the Spectrometer-Telescope for Imaging X-rays (STIX) on board the Solar Orbiter spacecraft, complemented by the Gamma-Ray Burst Monitor (GBM) aboard the Fermi mission, and the radio emission with Nançay Radioheliograph (NRH) and the ORFEES spectrograph. The extreme ultraviolet images from both Solar TErrestrial RElations Observatory (STEREO-A) and Solar Dynamics Observatory (SDO) were applied to trace the evolution of thermal plasma and coronal magnetic structures.Results. The radio spectrum at decimeter-to-meter wavelengths shows broadband continuum emission (type IV burst), which is a well-known radio signature of time-extended electron acceleration in eruptive flares. Both moving and stationary radio sources were identified. Energetic electrons were observed in X-rays up to 20 keV, displaying a significant correlation with the time evolution of the stationary type IV radio burst during the long duration decay phase, which lasted over 50 minutes. The X-ray photon spectral index is relatively steep with a value of around – 7.5 and the integrated electron flux above 30 keV is on the order of 1.6 × 1032 electron s−1.Conclusions. This case study provides for the first time evidence that HXR emission accompanies the onset of a stationary type IV radio burst. It ties together several pieces of evidence to support that non-thermal electrons are released into large-scale magnetic flux ropes during the post-impulsive phase of eruptive solar flares. The energies of the non-thermal electrons inferred from the X-ray spectral analysis confirm indirect estimates from radio observations. Electron acceleration processes appear as a significant signature of post-impulsive energy release, with energies in the range from several to tens of kiloelectron volts (keV)
Scraping d'Environnements Numériques de Travail et Analyse de Curriculums : un Cas d'Etude
No full textInternational audienceCurriculum research is often limited by the manual nature of data collection. Automating through computer science the collection and processing of data on educational content offers numerous opportunities, a consideration that we propose to take into account. illustrate with the case of the French Higher Schools of Architecture. In this article focused on methodology, we scraped data from Virtual Learning Environments to describe the use of the term “digital”, in the course titles of eleven establishments. We follow develop-ments in the use of terms over more than a decade, and contrast the situa-tions across institutions.Les recherches sur les curriculums sont souvent limitées par le caractère manuel de la collecte de données. Mobiliser des méthodes issues de l'informatique pour automatiser la collecte et le traitement de données sur des contenus d'enseignement offre un certain nombre d'opportunités en termes de passage à l'échelle des analyses, considération que nous nous proposons d'illustrer avec le cas des Ecoles Nationales Supérieures d'Architecture. Via des techniques fondées notamment sur le scraping de données issues d'Environnements Numériques de Travail, nous nous penchons dans cette réflexion méthodologique sur l'emploi du terme « numérique », dans les intitulés des cours de onze établissements. Nous suivons les évolutions de l'emploi des termes sur plus d'une décennie, et contrastons leur fréquence selon les établissements
Vénus et la Croix. À propos de la Copia de pareceres sobre el abuso de las pinturas lascivas, de 1632
No full textInternational audienceIn the summer of 1632, the Dominican Cristóbal de Torres y Motones (1573-1654), preacher to Philip IV after having occupied the same position for his father Philip III, was asked to write his opinion on the question of tolerating nude paintings. This opinion is placed at the beginning of those formulated by the theologians of the universities of Salamanca and Alcalá in the printed work entitled On the abuse of lascivious and dishonest figures and paintings; in which it is shown that it is a mortal sin to paint, sculpt and display them for all to see. In fact, the library of the Hispanic Society of America preserves in manuscript form the opinion issued by another royal preacher, a master of the previous one, and much more famous than him: Fray Hortensio Félix Paravicino. We are interested in the context that preceded and accompanied the drafting of these opinions on a matter of the utmost importance to the world of the Court: collections of mythological nudes, but also religious compositions. The lexicon attempts to define what happens when they are painted (and, to a lesser extent, sculpted), when they are viewed and when they are exhibited. I thus propose an initial study of this pivotal text in the artistic literature of around 1630.En el verano de 1632, se le pidió al dominico Cristóbal de Torres y Motones (1573-1654) —entonces predicador de Felipe IV, tras haberlo sido de su padre Felipe III— que escribiera su parecer sobre la cuestión de tolerar los desnudos en la pintura y escultura. Este parecer encabeza una colección compuesta por las opiniones de los teólogos de las Universidades de Salamanca y Alcalá en el impreso titulado Sobre el abuso de las figuras, y pinturas lasciuas, y deshonestas; en que se muestra que es pecado mortal pintarlas, esculpirlas, y tenerlas patentes donde sean vistas. La biblioteca de la Hispanic Society of America conserva el manuscrito del parecer de otro predicador real, maestro del anterior, y mucho más famoso que él: fray Hortensio Félix Paravicino. Explicamos el contexto que precedió y acompañó a la redacción de estos dictámenes sobre un caso de la máxima importancia para el mundo de la Corte, las colecciones de desnudos mitológicos: pero la cuestión atañe también a las composiciones religiosas. El léxico intenta circunscribir lo que sucede cuando uno pinta (y, en menor medida, cuando esculpe), expone y mira los desnudos. Este texto representó un punto de inflexión en la literatura artística en torno a 1630.À l’été 1632, on demanda au dominicain Cristóbal de Torres y Motones (1573-1654), — prédicateur de Philippe IV après l’avoir été de son père Philippe III — de rédiger son avis sur la question de tolérer les peintures de nus. Cet avis est placé au début des opinions formulées par les théologiens des universités de Salamanque et d’Alcalá dans l’imprimé intitulé Sur l’abus des figures et peintures lascives et malhonnêtes ; où l’on montre que c’est un péché mortel de les peindre, de les sculpter, et de les exposer aux yeux de tous. La bibliothèque de la Hispanic Society of America conserve sous forme manuscrite l’avis émis par un autre prédicateur royal, maître du précédent, et beaucoup plus célèbre que lui : Fray Hortensio Félix Paravicino. Nous nous intéressons au contexte qui précéda et accompagna la rédaction de ces avis portant sur une affaire de la plus haute importance pour le monde de la Cour, les collections de nus mythologiques, mais aussi sur les compositions religieuses. Le lexique tente de circonscrire ce qui se passe quand on les peint (et, dans une moindre mesure, quand on les sculpte), quand on les regarde et quand on les expose. Je propose ainsi une première étude de ce texte-charnière dans la littérature artistique autour de 1630