Showing papers by "Paul Sabatier University published in 2023"

Statistical Mapping of Magnetic Topology at Venus

Abstract: Venus lacks a significant intrinsic magnetic field, and thus, its atmosphere and ionosphere interact directly with the solar wind flow and magnetic field from the Sun. Interplanetary magnetic fields (IMF) can penetrate into the ionosphere when the upstream solar wind dynamic pressure is stronger than the ionospheric plasma pressure. Magnetic topology can be inferred at Venus if it is defined as the magnetic connectivity to the collisional atmosphere/ionosphere, rather than connectivity to the planet’s surface. Magnetic topology can be inferred from the pitch angle and energy distribution of superthermal (> ~1 eV) electrons. More specifically, the presence of loss cones in electron pitch angle distributions infers connectivity to the nightside collisional atmosphere and the presence of ionospheric photoelectrons (identified from electron energy distributions) indicates connectivity to the dayside collisional ionosphere. We design automated procedures to determine magnetic topology with electron and magnetic field measurements by the Venus Express spacecraft over its entire mission (2006-2014). This allows us to provide the first statistical mapping of magnetic topology at Venus. We also examine how the upstream drivers affect the low-altitude magnetic topology, revealing different magnetized states of the Venus ionosphere. We find that open and closed (a surprising topology not expected at Venus) fields cluster around the terminator and draped fields dominate other regions. Our results also reveal that there is more dayside magnetic connectivity in the -E (solar wind motional electric field) hemisphere than the +E hemisphere, and during solar maximum. During solar minimum, however, there is more nightside magnetic connectivity. Last but not the least, to understand the true nature of these magnetic topologies and broadly speaking the planet-solar wind interaction, we need to think about possible ways to measure the deeply penetrated magnetic fields at Venus and Mars.

The share of research infrastructure in comprehensive greenhouse gas budget for five French Earth and Space Science laboratories

Abstract: To maintain global warming below 1.5°C the last IPCC report indicates global greenhouse gas (GHG) emissions should be reduced by 45% and 80% before 2030 and 2050, respectively, reaching an average of 2 tCO2e.pers-1.yr-1 on Earth. Although responsibilities vary, substantial reductions must be implemented across all aspects of society including academia. It can even be argued that, given its role in informing and alerting the public about climate and ecological change, the scientific community should have a leading role and demonstrate exemplarity in terms of reducing its environmental impact.Here, we present a broad-scope GHG budget of five laboratories of the Observatoire Midi-Pyrénées in France, in 2019. The studied laboratories comprise 90 to 260 staff members each, with study fields encompassing the solid Earth and the environment, the superficial biosphere, oceanography and glaciology, atmospheric physics and chemistry, as well as astronomy and astrophysics.To assess GHG emissions, we follow standard procedure (see Mariette et al., Environ. Res.: Infrastruct. Sustain., 2022) in which any ‘activity data’ quantifying the usage of a given resource (e.g., in kWh of electricity, or km travelled by aircraft) is multiplied with an appropriate ‘emission factor’ quantifying the unitary carbon footprint of the resource (e.g., electricity production or air-travel). The quantified budget thus includes infrastructures usage, professional travel and expenses and an estimation of the GHG footprint of research infrastructures, in particular scientific satellites. For the latter, we adapted the methodology of Knödleser et al. (Nature Astronomy, 2022), in which the GHG footprint is estimated based on the launch mass or cost of the mission and the share attributable to a given lab depends on the fraction of world author affiliated with the lab who have published articles referring to the satellite, as extracted from the Web of Science database.We find that emissions related to the lab facilities (electricity, heating, air conditioning and waste) and to individual habits (commuting and lunch meals) both reach about 1 tCO2e.pers-1.yr-1. Unsurprisingly, professional trips significantly contribute to the overall budget (2-6 tCO2e.pers-1.yr-1) and are largely dominated by long-haul air travel. However, services and equipment equally contribute with more than 3-5 tCO2e.pers-1.yr-1. These numbers vary between the studied labs but higher (lower) values for services and equipment tends to compensate for lower (higher) values for professional trips. Furthermore, for three out of five laboratories observational data from research infrastructures represents the largest share of the emissions, with about 5-10 tCO2e.pers-1.yr-1. Although this last estimate is subject to large uncertainty and shows discrepancies between research fields, it suggests that current GHG budget should include at least a first order estimate of the footprint of research infrastructures and adapt reduction strategies accordingly.

3D gravity data inversion constrained by bounding interval ADMM regularization : Application to density distribution reconstruction of the Pyrenees chain lithosphere.

Abstract: Gravity inversion methods are able to recover density distributions in the Earth but they need to be strongly constrained using a variety of prior information. Here, we aim at inverting gravity data anomalies constrained by existing geological and density information on orogenic areas such as the Pyrenees where many geological and geophysical studies have been conducted for geophysical exploration purposes and fluid resources recovering of economic interest.To perform such inversion, we aim at constraining gravity inversions using covariance matrix defined as an interval distribution of possible density values. This covariance-like matrix is obtained by computing the probability of impact of lithological density variations on gravity residuals. Instead of using a Monte Carlo-like approach to sample density values in each rock unit, which may be too computationally expensive (in terms of number of forward calculations, memory and disk storage of all data needed for the probabilistic analysis), we calculate a series of probabilistic metrics associated to different combinations of density variations. For this, we select representative model variations and use partial plane experiment-based probabilistic method approach to estimate the impact of density variations on gravity data misfit. This drastically reduces the number of calculations and requires only a few tens of forward problems evaluations (instead of hundreds or thousands with Monte Carlo-like approach). Based on the impact of each prior lithological density variation, intervals of density variations can thus be estimated for each rock unit. This approach allows to define at low cost all these intervals, which can be interpreted as a reduced covariance matrix. For inversion using these intervals as constraints, we use an initial a priori density model obtained from a prior Vp model obtained by seismic teleseismic time-arrival inversion. To reconcile the so-obtained density model with gravity data, we perform gravity inversion constrained by bounded density intervals estimated from the probabilistic approach we propose. A dynamic Alternate Direction Multipliers Method regularization approach is used to constrain the inversion over such variation intervals. This allows us to obtain inverted models consistent with the geological structures modelled in the area and gravity data.We apply this inversion technique to the whole Pyrenees chain (southwest Europe) at a 2 km resolution and on a smaller zoomed 1 km resolution area constrained by outer information (density, ADMM variation intervals, …) provided by the 2km coarser inverted model. This way, new geological features can be inferred in the collisional intraplate Iberian-Eurasian region, in the axial zone and basement, and also at depth until the upper mantle. Besides, strong excesses of mass in the northern part and strong negative density contrasts in the south of the Pyrenees are appearing and increasing with depth when compared to previous prior models.

Progressive localization of a diffuse transtensional plate boundary: the example of the Iberia-Eurasia plate boundary during the opening of the Bay of Biscay (Late Jurassic-Early Cretaceous)

Abstract: Most plate kinematic reconstructions concerning the Iberian plate imply a major (>400 km) left-lateral displacement between Iberia and Eurasia during the opening of the Bay of Biscay (Late Jurassic-Early Cretaceous). In the past, authors identified the North Pyrenean Zone (NPZ) as the domain accommodating this lateral displacement, while more recent works tend to distribute the deformation in two or three transtensional corridors located in the NPZ and in the Iberian Chain basins. Nevertheless, field evidence contrasts with such models, since no structure seems to have accommodated such huge amount of displacement. Moreover, debate exists concerning the timing of the left-lateral displacement between Iberia and Eurasia (Late Jurassic vs Early Cretaceous).We present a review of the tectono-sedimentary and kinematic evolution of rift basins distributed across the wide Iberia-Eurasia plate boundary that recorded the Late Jurassic-Early Cretaceous rifting phase, from the Iberian Chain basins (in the southwest) to the northern part of the Aquitaine domain aligned with the Armorican Margin (to the northeast). To the first order, these basins experienced the same tectonic evolution, with an initial Permian-Triassic rifting phase related to the breakup of Pangea, and a subsequent Late Jurassic-Early Cretaceous rifting phase related to the opening of the Bay of Biscay. For this latter phase, authors have proposed contrasting kinematic models, with opening mechanisms varying between orthogonal rifting and transtensional/pull-apart tectonics. Our review allows to propose a reappraisal of the kinematic evolution of the Iberia-Eurasia diffuse plate boundary during the Late Jurassic-Early Cretaceous rifting, which consists in four phases: (i) a Late Jurassic phase of transtensional deformation localized at the borders of the system (Asturian Basin/Southwesternmost Iberian Chain basins and Armorican Margin), while the rest of the basins underwent orthogonal rifting, contemporaneous with rifting in the Bay of Biscay margins; (ii) a Neocomian phase of generalized marine regression; (iii) a Barremian-Early Albian phase of distributed left-lateral transtension, contemporaneous with crustal breakup in the Bay of Biscay; (iv) an Albian-Cenomanian phase of left-lateral transtension localized in the Basque-Cantabrian/North Pyrenean corridor, contemporaneous with ocean spreading in the Bay of Biscay, while the rest of the rift basins within the plate boundary became tectonically inactive. This evolution highlights a trend of progressive localization of the plate boundary from the Late Jurassic to the Early Cretaceous in response to the different tectonic phases of the Bay of Biscay margins. This work also allows to highlight the role of some rift basins in accommodating part of the deformation between Iberia and Eurasia which have been often disregarded, due to their position below the Cenozoic cover of the Pyrenean foreland basins, such as the Ebro and Aquitaine domains.

Venus Dynamics Tracer (VdT) - a mission dedicated for in-situ measurements of the Venus atmosphere.

Abstract: Recent Venus missions (Venus Express and Akatsuki) provided a large-scale view of Venus atmosphere and discovered new phenomena, such as high-altitude extension of the mountain wave to the cloud layer and a dawn-dusk asymmetry in the ionospheric motion.  The superrotation of the cloud layer is assumed to be driven by the thermal tide but its relation to any meridional convection or waves is still unknown.  The key to understand all these phenomena is to determine the multi-step re-distribution of the absorbed solar radiation to other forms of energy: (1) internal energy; including temperature, latent heat, and chemical energy (2) kinetic energy both in large scale flows/waves and in minor deviations of convection motions, (3) electric energy including ionization. To understand how the motion of Venus atmosphere is driven by the energy originating from the absorption of solar radiation, we proposed Venus Dynamics Tracer (VdT), a mission for in-situ measurements, as a response to the ESA call for new M-class missions.  Specific targets were two major energy absorption regions: the cloud layer and the ionized upper atmosphere. The scientific goals were to investigate (a) the roles of the vertical and meridional circulation in maintaining major atmospheric dynamics near the cloud layer where visible light is absorbed and drives the vertical motions of the air, and to understand the (b) global dynamics of ions and neutrals in the upper atmosphere where EUV is absorbed both by neutrals and ions and where energy and momentum are transferred between them.  For the first target, multiple-balloons are deployed for in situ observations with supporting camera/s on an orbiter giving global context. For the second target, the motions of ions and neutrals are directly measured.  This presentation discusses required measurements to answer the scientific goals.  

Reply on RC2

Abstract: Abstract. Low level stratiform clouds (LLSCs) covering a large area appear frequently during the wet monsoon season in southern West Africa. This region is also a place where different types of aerosols coexist, including biomass burning aerosols coming from Central and South Africa and anthropogenic aerosols emitted from local activities. We investigate the semi-direct and indirect effects of these aerosols on the diurnal cycle of LLSCs by constructing a case study based on airborne and ground-based observations from the Dynamic-Aerosol-Chemistry-Cloud-Interaction in West Africa (DACCIWA) field campaign. This case is modelled using a Large Eddy Simulation (LES) model with fine scale resolution and in-situ aerosol measurements including size distribution and chemical composition. The model has successfully reproduced the observed life cycle of the LLSC, from stratus formation to stabilization during the night, to upward development after sunrise until breakup of cloud deck in late afternoon. Various sensitivity simulations using different measured aerosol profiles also suggest that aerosols can affect the cloud life cycle through both the indirect and semi-direct effect. Despite precipitation produced by the modeled cloud is nearly negligible, cloud lifetime is still sensitive to the aerosol concentration. As expected, modeled cloud microphysical features including cloud droplet number concentration, mean radius, and thus cloud reflectivity are all controlled by aerosol concentration. However, it is found that the difference in cloud reflectivity is not always the only factor in determining the variation of the incoming solar radiation at ground and cloud life cycle specifically beyond sunrise. Instead, the difference in cloud-void space brought by dry air entrainment from above and thus the speed of consequent evaporation – also influenced by aerosol concentration, is another important factor to consider. Results have shown that clouds in the case with lower aerosol concentration and larger droplet size appear to be less affected by entrainment and convection. In addition, we have found that an excessive atmospheric heating up to 12 K day⁻¹ produced by absorbing black carbon aerosols (BC) in our modeled cases can also affect the life cycle of modeled clouds. Such a heating is found to lower the height of cloud top and stabilize the cloud layer, resulting a less extent in vertical development and accelerating cloud breakup. The semi-direct effect impacts on indirect effect by reducing cloud reflectivity particularly in case of polluted environment. Finally, semi-direct effect is found to contribute positively to the indirect radiative forcing due to a decreased cloud-void space, and negatively by causing thinner clouds that would break-up faster in late afternoon, all depending on the phase in stratiform cloud diurnal cycle.

The Place of Digital and Artificial Intelligence in Medical Research

Abstract: Advances in the performance of computers and new algorithms now make it possible to manage and analyze faster and more data (big data, data sciences, artificial intelligence). Software’s are now available in almost all areas of health. These are medical devices with regard to European legislation. In this presentation we will show the contribution of digital technologies in clinical trials (A) and in other health research (B), to end with ethical considerations on the use of digital and artificial intelligence in research in health (C).

How to reduce the carbon footprint of Earth and Space Science? Potential strategies based on a comprehensive greenhouse gas budget for five French labs

Abstract: To maintain global warming below 1.5°C the last IPCC report indicates global greenhouse gas (GHG) emissions should be reduced by 45% and 80% before 2030 and 2050, respectively, reaching an average of 2tCO2e.pers-1.yr-1 on Earth. Recent estimates of the carbon footprint of universities and research centers accounting for indirect emissions often exceed 10tCO2e.pers-1.yr-1.Here we find similar or higher values (10-30tCO2e.pers-1.yr-1) for the year 2019 for five research labs encompassing the solid Earth and the environment, the superficial biosphere, oceanography and glaciology, atmospheric physics and chemistry, and astronomy and astrophysics. These values are derived through a common procedure (see Mariette et al., 2022) in which any activity data quantifying the usage of a given resource (e.g., in kWh or km) is multiplied by an appropriate emission factor quantifying the unitary carbon footprint of the resource (e.g., electricity production or air travel). Our budget quantifies the share of emissions from local facilities (about 1tCO2e.pers-1.yr-1), lunch meals and commuting (about 1tCO2e.pers-1.yr-1), professional trips (2-6tCO2e.pers-1.yr-1), services and equipment (3-5tCO2e.pers-1.yr-1), and the use of observational data from research infrastructures, in particular scientific satellites (up to 10tCO2e.pers-1.yr-1; derived similarly to Knödlseder et al., 2022).These numbers imply radical changes to make scientific activity sustainable and have strong implications on potential strategies to reduce GHG emissions. For example, a predominant discussion in the literature in the past years focused on avoiding air travel. However, in our case, shifting all national travels to train or halving the number of plane trips would reduce the total emissions by a fraction only. Similarly, any strategy targeting local building efficiency or individual habits will little influence the budget. In contrast, reducing or changing practice for services and equipment may have stronger impact but requires collective thinking, especially for research infrastructures that are planned and managed at national and international levels.The sheer magnitude of our GHG emissions questions the degree of reduction that can be achieved without redirection of scientific activity. We present and discuss examples of changes such as shifting to interdisciplinary research including social sciences, focusing on archived data, relocating field work, or engaging more with students and society.

Opinion: New directions in atmospheric research offered by research infrastructures combined with open and data-intensive science

Abstract: Abstract. Acquiring and distributing essential information for understanding global biogeochemical interactions between the atmosphere and ecosystems, and how climate-ecosystem feedback loops may change atmospheric composition in the future is a fundamental pre-requisite for societal resilience in view of climate change. Particularly, the detection of trends and periodicity in the presence of greenhouse gases and short-lived climate-active atmospheric constituents is an important aspect of climate science. Thus, the availability of an easy and fast access to reliable, long-term, and high-quality environmental data is recognized as fundamental for research and for developing environmental prediction and assessment services. In our Opinion Article, we develop the role environmental research infrastructures in Europe (ENVRI RIs) and particularly the atmosphere-centred research infrastructures ACTRIS, IAGOS and ICOS can assume with their capacities for standardised acquisition and reporting of long-term and high-quality observational data, complemented by rich metadata, for the provision of data by open access, and for data interoperability across different research fields including all fields of environmental sciences and beyond. Resulting from these capacities in data collection and provision, we elaborate on the novel research opportunities in atmospheric sciences which evolve from the combination of open-access and interoperable observational data, tools and technologies offered by data-intensive science, and the emerging service ecosystem of the collaboration platform ENVRI-Hub, hosted by the European Open Science Cloud.

Reply on EC1

Abstract: Abstract. Low level stratiform clouds (LLSCs) covering a large area appear frequently during the wet monsoon season in southern West Africa. This region is also a place where different types of aerosols coexist, including biomass burning aerosols coming from Central and South Africa and anthropogenic aerosols emitted from local activities. We investigate the semi-direct and indirect effects of these aerosols on the diurnal cycle of LLSCs by constructing a case study based on airborne and ground-based observations from the Dynamic-Aerosol-Chemistry-Cloud-Interaction in West Africa (DACCIWA) field campaign. This case is modelled using a Large Eddy Simulation (LES) model with fine scale resolution and in-situ aerosol measurements including size distribution and chemical composition. The model has successfully reproduced the observed life cycle of the LLSC, from stratus formation to stabilization during the night, to upward development after sunrise until breakup of cloud deck in late afternoon. Various sensitivity simulations using different measured aerosol profiles also suggest that aerosols can affect the cloud life cycle through both the indirect and semi-direct effect. Despite precipitation produced by the modeled cloud is nearly negligible, cloud lifetime is still sensitive to the aerosol concentration. As expected, modeled cloud microphysical features including cloud droplet number concentration, mean radius, and thus cloud reflectivity are all controlled by aerosol concentration. However, it is found that the difference in cloud reflectivity is not always the only factor in determining the variation of the incoming solar radiation at ground and cloud life cycle specifically beyond sunrise. Instead, the difference in cloud-void space brought by dry air entrainment from above and thus the speed of consequent evaporation – also influenced by aerosol concentration, is another important factor to consider. Results have shown that clouds in the case with lower aerosol concentration and larger droplet size appear to be less affected by entrainment and convection. In addition, we have found that an excessive atmospheric heating up to 12 K day⁻¹ produced by absorbing black carbon aerosols (BC) in our modeled cases can also affect the life cycle of modeled clouds. Such a heating is found to lower the height of cloud top and stabilize the cloud layer, resulting a less extent in vertical development and accelerating cloud breakup. The semi-direct effect impacts on indirect effect by reducing cloud reflectivity particularly in case of polluted environment. Finally, semi-direct effect is found to contribute positively to the indirect radiative forcing due to a decreased cloud-void space, and negatively by causing thinner clouds that would break-up faster in late afternoon, all depending on the phase in stratiform cloud diurnal cycle.

Every Museum Label for All? Reflection on Inclusive and Communicative Writing

Abstract: Since our PhD, we aim to rethink the transposition of universal design (UD) in museums for narratives, specifically on labels. We have conceptualised a model of universal label, adding inclusive and communicative writing: inclusive, by using universal design merging on the same device several forms of communication (sign language, Braille, easy to read); communicative, because it explains and learns how citizens perceived as disabled communicate. UD writing could initiate and encourage communication. In this paper, we applied our reflections on UD writing to the label of The Mona Lisa at the Louvre Museum.

Malicious Human Behaviour in Information System Security: Contribution to a Threat Model for Event Detection Algorithms

Abstract: Among the issues the information system security community has to fix, the security of both data and algorithms is a concern. The security of algorithms is dependent on the reliability of the input data. This reliability is questioned, especially when the data is generated by humans (or bots operated by humans), such as in online social networks. Event detection algorithms are an example of technology using this type of data, but the question of the security is not systematically considered in this literature. We propose in this paper a first contribution to a threat model to overcome this problem. This threat model is composed of a description of the subject we are modelling, assumptions made, potential threats and defence strategies. This threat model includes an attack classification and defensive strategies which can be useful for anyone who wants to create a resilient event detection algorithm using online social networks.

Dehydration of the Subducting Juan de Fuca Plate and Fluid Pathways Revealed by Full Waveform Inversion of Teleseismic P and SH Waves in Central Oregon

Abstract: The dehydration of subducting slabs expels a massive amount of water into the forearc and backarc mantle which is responsible for the serpentinization of the mantle wedge, as well as the production of melt and arc magmatism. These processes are expected to have characteristic signatures in density and seismic velocities models, which remain largely elusive to date due to the limited spatial resolution of classical passive tomographic approaches. Here we present a tomographic model of density, VP, VS, and VP/VS beneath central Oregon, obtained by inverting complete teleseismic P and SH waveforms recorded by the CASC93 temporary experiment. The final model shows an east-dipping low-velocity layer less than 10 km thick that can be associated with the fluid-saturated Juan de Fuca oceanic crust. The distribution of tremors at the surface closely coincides with the horizontal extent of this low-velocity layer. Below 40 km depth, seismic velocities and density increase progressively to the values of a typical mantle. This transitional domain corresponds to the eclogitization of the oceanic crust. Silica-saturated fluids released by pore collapse migrate upward, producing serpentinization reactions in the forearc mantle that lower the density and seismic velocities. The very low VP/VS ratio documented in the Cascadia forearc crust is evidence that these silica-saturated fluids reach the crust, where they produce extensive quartz mineralization. At greater depth, a low seismic velocity and high VP/VS ratio anomaly provides evidence for partial melting at around 75 km depth beneath the volcanic arc.

Complexes Featuring a <i>cis</i>‐[MUM] Core (M=Rh, Ir): A New Route to Uranium‐Metal Multiple Bonds

Abstract: Although examples of multiple bonds between actinide elements and main-group elements are quite common, studies of the multiple bonds between actinide elements and transition metals are extremely rare owing to difficulties associated with their synthesis. Here we report the first example of molecular uranium complexes featuring a cis-[M U M] core (M=Rh, Ir), which exhibits an unprecedented arrangement of two M U double dative bond linkages to a single U center. These complexes were prepared by the reactions of chlorine-bridged heterometallic complexes [{U{N(CH3)(CH2CH2NPiPr2)2}(Cl)2[(μ-Cl)M(COD)]2}] (M=Rh, Ir) with MeMgBr or MeLi, a new method for the construction of species with U−M multiple bonds. Theoretical calculations including dispersion confirmed the presence of two U M double dative bonds in these complexes. This study not only enriches the U M multiple bond chemistry, but also provides a new opportunity to explore the bonding of actinide elements.

Investigating the Source of the Slow Solar Wind Using Solar Orbiter Observations and the IRAP Solar Atmospheric Model

Abstract: The slow solar wind can be separated into at least two different components: a dense, variable wind produced by helmet streamers and a more tenuous and Alfv&#233;nic component emitted by coronal holes. Previous studies have shown that the slow Alfv&#233;nic wind is associated with enhanced alpha particle abundances, strong proton beams, and large alpha-to-proton temperature ratios: typical properties of the fast wind known to originate from inside large coronal holes. Recent combined in-situ and remote-observation campaigns by the Solar Orbiter mission exploiting the Proton and Alpha particle Sensor (SWA-PAS) can help us to study the relationship between the Alfv&#233;nic slow wind and coronal holes. We exploit these latest observations in conjunction with the newly-developed multi-species IRAP Solar Atmospheric Model (ISAM) model to study the coronal conditions that favour the production of an Alfv&#233;nic slow wind. ISAM simulates the coupled transport of both neutral and charged particles between the chromosphere and the corona, including a self-consistent treatment of collisional and ionisation processes, as well as detailed energy and heat flux conservation equations. In this study we discuss how the simulated alpha to proton ratios are modulated in response to different coronal heating rates and discuss these simulation results in light of recent Solar Orbiter measurements. The results presented here were funded by the European Research Council through the SLOW SOURCE project grant number DLV-819189.

Neurons from pre-motor areas to the Mushroom bodies can orchestrate latent visual learning in navigating insects.

Abstract: Spatial learning is peculiar. It can occur continuously and stimuli of the world need to be encoded according to some spatial organisation. Recent evidence showed that insects categorise visual memories as whether their gaze is facing left vs. right from their goal, but how such categorisation is achieved during learning remains unknown. Here we analysed the movements of ants exploring the world around their nest, and used a biologically constrained neural model to show that such parallel, lateralized visual memories can be acquired straightforwardly and continuously as the agent explore the world. During learning, left and right visual memories can be formed in different neural comportments (of the mushroom bodies lobes) through existing lateralised dopaminergic neural feedback from pre-motor areas (the lateral accessory lobes) receiving output from path integration (in the central complex). As a result, path integration organises visual learning internally, without the need to be expressed through behaviour; and therefore, views can be learnt continuously (without suffering memory overload) while the insect is free to explore the world randomly or using any other navigational mechanism. After learning, this circuit produces robust homing performance in a 3D reconstructed natural habitat despite a noisy visual recognition performance. Overall this illustrates how continuous bidirectional relationships between pre-motor areas and visual memory centres can orchestrate latent spatial learning and produce efficient navigation behaviour.

Reply on RC1

Abstract: Abstract. Low level stratiform clouds (LLSCs) covering a large area appear frequently during the wet monsoon season in southern West Africa. This region is also a place where different types of aerosols coexist, including biomass burning aerosols coming from Central and South Africa and anthropogenic aerosols emitted from local activities. We investigate the semi-direct and indirect effects of these aerosols on the diurnal cycle of LLSCs by constructing a case study based on airborne and ground-based observations from the Dynamic-Aerosol-Chemistry-Cloud-Interaction in West Africa (DACCIWA) field campaign. This case is modelled using a Large Eddy Simulation (LES) model with fine scale resolution and in-situ aerosol measurements including size distribution and chemical composition. The model has successfully reproduced the observed life cycle of the LLSC, from stratus formation to stabilization during the night, to upward development after sunrise until breakup of cloud deck in late afternoon. Various sensitivity simulations using different measured aerosol profiles also suggest that aerosols can affect the cloud life cycle through both the indirect and semi-direct effect. Despite precipitation produced by the modeled cloud is nearly negligible, cloud lifetime is still sensitive to the aerosol concentration. As expected, modeled cloud microphysical features including cloud droplet number concentration, mean radius, and thus cloud reflectivity are all controlled by aerosol concentration. However, it is found that the difference in cloud reflectivity is not always the only factor in determining the variation of the incoming solar radiation at ground and cloud life cycle specifically beyond sunrise. Instead, the difference in cloud-void space brought by dry air entrainment from above and thus the speed of consequent evaporation – also influenced by aerosol concentration, is another important factor to consider. Results have shown that clouds in the case with lower aerosol concentration and larger droplet size appear to be less affected by entrainment and convection. In addition, we have found that an excessive atmospheric heating up to 12 K day⁻¹ produced by absorbing black carbon aerosols (BC) in our modeled cases can also affect the life cycle of modeled clouds. Such a heating is found to lower the height of cloud top and stabilize the cloud layer, resulting a less extent in vertical development and accelerating cloud breakup. The semi-direct effect impacts on indirect effect by reducing cloud reflectivity particularly in case of polluted environment. Finally, semi-direct effect is found to contribute positively to the indirect radiative forcing due to a decreased cloud-void space, and negatively by causing thinner clouds that would break-up faster in late afternoon, all depending on the phase in stratiform cloud diurnal cycle.

Electron populations observed by Mercury Electron Analyzer onboard Mio/BepiColombo during its second Mercury flyby

Abstract: BepiColombo was launched in October 2018 and is currently en route to Mercury. Although its orbit insertion is planned for December 2025, BepiColombo will acquire new measurements during planetary flybys. During the cruise phase, the two spacecraft are docked together with Mio being protected behind the MOSIF sun shield. Thus, only partial observations of plasma distribution functions can be obtained by the Mercury Plasma Particle Experiment (MPPE) onboard Mio. However, since electrons have small Larmor radii and more isotropic distributions even in the solar wind, the two Mercury Electron Analyzer (MEA) of MPPE will provide us with new and unique measurements in the range of 5 eV to 3 keV when in solar wind mode and 3 eV to ~ 26 keV when in magnetospheric mode. We will present the interesting observations obtained by MEA onboard Mio/BepiColombo during its second Mercury flyby that happened on the 23rd of June, 2022. In particular we will focus on the properties of the low- and high-energy electron populations observed during its crossing of Mercury&#8217;s magnetosphere.

Crustal thickness estimation and interpretation in Greenland from space gravity data.

Abstract: Uses of recent gravity data, from Gravity Recovery And Climate Experiment (GRACE) and Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellites, are an effective solution to obtain stable data over Greenland. Here, we used the GOCO06s and EGM2008 gravity models, as well as topography and ice thickness data from BedMachine v4, to reverse the complete Bouguer anomaly and obtain the thickness of the Greenlandic crust. Our results indicate an average thickness ranging between 45 and 47 &#177;4.5 km, with thin zones of 40 to 44 &#177;4.5 km and thick structures varying from 48 &#177;4.5 km up to 57 &#177;4.5 km. Our results are consistent with other studies albeit locally different on the coasts. A geological interpretation of our results has been completed and infer the presence of the Archean craton, the Paleoproterozoic domain, the Caledonian and Ellesmerian orogens, as well as another structure that could correspond to Paleo-Neoproterozoic basins.

The self-gravitating Fermi gas in Newtonian gravity and general relativity

Abstract: We review the history of the self-gravitating Fermi gas in Newtonian gravity and general relativity. We mention applications to white dwarfs, neutron stars and dark matter halos. We describe the nature of instabilities and phase transitions in the self-gravitating Fermi gas as energy (microcanonical ensemble) or temperature (canonical ensemble) is reduced. When $NN_{\rm OV}$, a new turning point appears at an energy $E"_c$ below which the system experiences a gravitational collapse towards a black hole [P.H. Chavanis, G. Alberti, Phys. Lett. B 801, 135155 (2020)]. When $N_{\rm OV}N'_*$, the condensed branch disappears and the instability at $E_c$ directly leads to a black hole. We discuss implications of these results for dark matter halos made of massive neutrinos.

Tectono-magmatic and kinematic evolution of the Africa-Europe plate boundary: from Cadomian subduction to Western Mediterranean tectonics

Abstract: Processes driving orogenic styles and long-term isostatic versus dynamic support of the topography have been largely debated in domains of plate convergence. The tectonic evolution of orogens reflect the interactions between mantle flow driving plates and the inherited rheology and composition of moving plates. Here we show that the tectono-magmatic evolution of the European lithospheric mantle and structure, which inherits past subduction/collision (e.g. Cadomian, Variscan) and rifting events (Tethys/Atlantic), control first-order crust-mantle coupling, plate-mantle coupling, defining Alpine-type orogens. The lack of thermal relaxation needed to maintain rheological contrasts over several hundreds of millions of years requires high mantle heat &#64258;ux below Central Europe since at least the Permian. A combination of edge-driven convection on craton margins and asthenospheric &#64258;ow triggered by rift propagation during the Atlantic and Tethys rifting is suggested to be the main source of heat. Timing and rates of exhumation recorded across Western Europe during the Cenozoic convergence reveal an additional control by the architecture of Mesozoic rifted margins that defined a complex array of small continental blocks with European affinity (e.g. S-Iberia, Ebro/Sardinia-Corsica) caught between the East European and West African cratons, and Adria. By 50 Ma the acceleration of orogenic exhumation, from the High Atlas to the Pyrenees, occurred synchronously with the onset of extension and magmatism in the West European Rift. Extension marks the onset of distinct orogenic evolution between Western Europe (Iberia) and the Alps (Adria) in the east, heralding the opening of the Western Mediterranean. While the details of the Cenozoic topographic history of peri-Mediterranean orogens are understood to be controlled by the rheology and architecture of rifted margins combined with changing large-scale kinematic boundary conditions (e.g. Atlas, Betics, Pyrenees, Alps), their post-10 Ma, quaternary to current surface and tectonic evolution appears to illustrate increasing control by magmatism and flow at the asthenosphere-lithosphere boundary.

Specific profiles of new-onset vs. non-inaugural status epilepticus: From diagnosis to 1-year outcome

Abstract: While new-onset status epilepticus (NOSE) is a harbinger of chronic epilepsy, prospective medical data are sparse in terms of specifying whether the evolution of status epilepticus (SE) and seizure expression in NOSE resembles what occurs in patients who have already been diagnosed with epilepsy [non-inaugural SE (NISE)] in all aspects apart from its inaugural nature. The aim of this study was to compare the clinical, MRI, and EEG features that could distinguish NOSE from NISE. We conducted a prospective monocentric study in which all patients ≥18 years admitted for SE over a 6-month period were included. A total of 109 patients (63 NISE and 46 NOSE cases) were included. Despite similar modified Rankin scores before SE, several aspects of the clinical history distinguished NOSE from NISE patients. NOSE patients were older and frequently had neurological comorbidity and preexisting cognitive decline, but they had a similar prevalence of alcohol consumption to NISE patients. NOSE and NISE evolve in the same proportions as refractory SE (62.5% NOSE, 61% NISE) and share common features such as the same incidence (33% NOSE, 42% NISE, and p = 0.53) and volumes of peri-ictal abnormalities on MRI. However, in NOSE patients, we observed greater non-convulsive semiology (21.7% NOSE, 6% NISE, and p = 0.02), more periodic lateral discharges on EEG ( p = 0.004), later diagnosis, and higher severity according to the STESS and EMSE scales ( p &lt; 0.0001). Mortality occurred in 32.6% of NOSE patients and 21% of NISE patients at 1 year ( p = 0.19), but with different causes of death occurring at different time points: more early deaths directly linked to SE at 1 month occurred in the NOSE group, while there were more remote deaths linked to causal brain lesions in the NISE group at final follow-up. In survivors, 43.6% of the NOSE cases developed into epilepsy. Despite acute causal brain lesions, the novelty related to its inaugural nature is still too often associated with a delay in diagnosing SE and a poorer outcome, which justifies the need to more clearly specify the various types of SE to constantly raise awareness among clinicians. These results highlight the relevance of including novelty-related criteria, clinical history, and temporality of occurrence in the nosology of SE.

The ENVRI-Hub as a service for accelerating FAIRification of the Environment Domain Research Infrastructures

Abstract: European Environmental Research Infrastructures (ENVRIs) on the ESFRI level are core facilities for providing data, research products and services from the four subdomains of Earth system science &#8211; Atmosphere, Marine, Solid Earth, and Biodiversity/Terrestrial Ecosystems. The ENVRI Cluster represents the core component of the European environmental research infrastructure landscape, with the ENVRI community as their common forum for collaboration and co-creation. The topics covered by the ENVRIs span the entire range of scientific objectives relevant for Earth system monitoring.The community has developed the ENVRI-Hub as a central platform for accessing interdisciplinary FAIRfied environmental research assets, serving as an essential ENVRI community's interface to the European Open Science Cloud (EOSC). Through the ENVRI-Hub, the ENVRI community shares their FAIRness experience, technologies, and training as well as research products and services. The architecture and functionalities of the ENVRI-Hub are driven by scientific applications, use cases and user needs. Its three main pillars are the ENVRI Knowledge Base as the human interface to the ENVRI ecosystem, the ENVRI Catalogue of Services as the machine-actionable interface to the ENVRI ecosystem, and finally, subdomain and cross-domain scientific use cases as demonstrators for the capabilities of service provision among ENVRIs and across Science Clusters.The Science Demonstrators are being developed by several RIs in parallel. They are the key product to express the ENVRI-Hub&#8217;s potential regarding easy access to metadata and services, data discovery, as well as the promotion of interoperability in science across sub-domains. Science Demonstrators are built with Jupyter Notebooks - an open-source web application that allows one to create and share&#160;documents that contain live code, equations, visualizations, and narrative text. Uses include cross domain data access, data cleaning and transformation, numerical simulation, statistical modelling, data visualization, machine learning, and much more. The Jupyter Notebook environment forms the nucleus of the future ENVRI Virtual Research Environment.The ENVRI Science Demonstrators and Science Projects in the Horizon 2020 project EOSC Future aim at demonstrating how joint projects can address major challenges for Europe&#8217;s societies and how research infrastructures can support Horizon Europe&#8217;s missions within the EOSC. Presented Science Demonstrators cover one ENV domain wide service on the collocation of sampling sites, and two science cases from atmospheric and marine research, respectively.Acknowledgement: ENVRI-FAIR has received funding from the EU Horizon 2020 research and innovation programme under grant agreement No 824068. Part of the work is funded by the EU Horizon 2020 project EOSC Future under grant agreement No 101017536. This work is only possible with the collaboration of the ENVRI-FAIR partners and thanks to the joint efforts of the whole ENVRI-Hub team.

Lithosphere-asthenosphere structure and impact on serpentinization processes and topography across the plate boundary between Iberia and Europe

Abstract: The tectonic evolution of the plate boundary between Iberia and Europe since the Variscan and more clearly since the Mesozoic rifting is at the origin of heterogeneities of densities and structure, in the crust and the mantle, which have an impact on the distribution of the current stresses and post-orogenic uplift in the Pyrenees. Here, we investigate the lithosphere structure across the Pyrenees and Western Europe using LitMod2D that integrates geophysical and petrological data sets to produce the thermal, density, and seismic velocity structure of the lithosphere and upper mantle. Of particular interest is the chemical composition of the mantle, including the degree of serpentinization near the North Pyrenean Fault (>10 km), and the shape of the lithosphere-asthenosphere boundary at a larger scale (>100 km). The topography and geophysical constraints, including LAB geometry, Vs, Vp data are well reproduced for a weak fertile Phanerozoic lithosphere. Our results suggest that accounting for serpentinization allows fitting second-order gravity and seismological features in the lithosphere, but not topography which is controlled to first-order by high lateral variability in crustal thickness and lithosphere strength.

Comparison and analysis of the long-term dynamics of GNSS orbits

Abstract: The precision of the GNSS positioning depends on the accuracy and stability of the GNSS satellite orbits. Indeed, the analysis of the GNSS precise orbits determined by the IGS analysis centers shows different long-term behavior in the eccentricities and inclinations of GPS satellites, compared to GLONASS and Galileo satellites. This contribution focuses on analyzing sources of long-term dynamics in the GNSS orbits, particularly in the GPS orbits, and the influence of the constellation design. We investigate orbital resonances resulting from external accelerations such as lunisolar gravitation by semi-analytical simulations and compare the dynamical response of the four available constellations: GPS, Galileo, GLONASS, and BeiDou. Finally, we assess the impact of this different dynamical behavior on Precise Point Positioning (PPP).