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High-resolution income projections over the 21st century in Europe consistent with the Shared Socioeconomic Pathways
No full textInternational audienceAbstract Climate risk in Europe is unevenly distributed among the population and is projected to increase substantially over the 21st century due to evolving climatic and socioeconomic conditions. Projections of vulnerability drivers, such as income distribution, are needed for assessing future climate risk. In Europe, existing studies typically rely on inadequate proxies, such as gross domestic product per capita, to account for future vulnerability associated with income levels. This study presents a novel top–down iterative methodology to produce decadal, high-resolution (1 km) maps of disposable income across Europe for the 21st century consistent with the Shared Socioeconomic Pathways (SSPs). More specifically, our method aligns with SSP narratives on future economic growth, income distribution, population dynamics and settlement expansion. We illustrate two possible applications of these projections by analysing future shifts in income distribution and estimating the evolution of the number of people at risk of poverty across different development pathways. In highly unequal pathways (SSP3 and SSP4), poverty levels across Europe are projected to increase significantly, with over 30% of the population at risk of poverty by 2100. On the other hand, pathways with high economic growth, specifically SSP1 and SSP5, result in a decrease in poverty rates. This dataset can serve as a resource for examining future vulnerabilities to climate change and socioeconomic inequalities, providing valuable insights for more effective climate risk assessments and targeted adaptation strategies
Observing the Diurnal Variation of Atmospheric Ozone From the Geostationary Interferometric Infrared Sounder (GIIRS) Over East Asia
No full textInternational audienceOzone is an important atmospheric constituent, exerting a pivotal influence on atmospheric chemistry, air quality, and climate change. The monitoring of its distribution and variation is crucial for advancing our understanding of ozone development and related processes. This study presents the first spatial and temporal distributions of total ozone columns (TOC) retrieved from the Geostationary Interferometric Infrared Sounder (GIIRS), on board China's FengYun‐4B satellite (FY‐4B/GIIRS) launched in 2021. Particularly, we focus on the variations of TOCs in East Asia from diurnal to seasonal time scales. Retrievals are implemented using spectra from March, June, September, and December, representing different seasons. The results show that the degree of freedom for the signal (DOFS) typically exhibited a range of 0.8–1.4, with the vertical detection sensitivity of GIIRS peaking in the upper troposphere/lower stratosphere (UTLS) region, where the ozone variability is the highest. Collocation comparisons with the Infrared Atmospheric Sounding Interferometer (IASI) retrievals, the Ozone Monitoring Instrument (OMI) measurements, the European Center for Medium‐Range Weather Forecasts (ECMWF) Reanalysis v5 (ERA5) simulations, and in situ ozone observations show good agreement. The comparisons of TOCs between GIIRS, Pandora and ERA5 at different latitudes and different time scales demonstrate the ability of FY‐4B/GIIRS in capturing the temporal and latitudinal ozone variations, particularly at middle and high latitudes. Our work demonstrates that FY‐4B/GIIRS has good capability to track ozone variations from diurnal to seasonal in East Asia, which will contribute to the understanding of regional and global ozone variations
Internal variability effect doped by climate change drove the 2023 marine heat extreme in the North Atlantic
No full textInternational audienceThe year 2023 shattered numerous heat records both globally and regionally. We here focus on the drivers of the unprecedented warm sea surface temperature (SST) anomalies which started in the North Atlantic Ocean in early summer and persisted later on. Evidence is provided that 2023 should be interpreted as an extreme event in a warmer world because of superimposed internal variability on top of human forcing, which altogether, made the 2023 event all-time high due to extreme air-sea surface fluxes in the subtropics and eastern basin. The effect of internal variability has been considerably boosted by the long-term ocean stratification increase due to combined anthropogenically-driven ocean warming and multidecadal variability. The 2023 event would have been impossible to occur without anthropogenically-driven climate change but at the current warmer background climate state, it is assessed as a decadal-type event when considering the full North Atlantic ocean and a centennial event in the subtropics and eastern basin. Considering the regional distribution of anomalies is crucial for risk assessment in a warming climate
The New Titan Planetary Climate Model. I. Seasonal Variations of the Thermal Structure and Circulation in the Stratosphere
No full textInternational audienceObservations of Titan through Cassini’s mission allowed Saturn’s moon’s stratospheric thermal structure and composition to be mapped over half a Titan year. Seasonal variations revealed various unexplained phenomena, such as mechanisms within the polar vortex, thermal structure evolution at high latitudes, and the impact of the enrichment in trace compounds during winter polar nights. We have developed the Titan Planetary Climate Model (Titan PCM)—an improved version of the IPSL Titan Global Climate Model (GCM)—including upgraded radiative transfer, now based on a flexible correlated- k method, updated spectroscopic data on gases, and integration of a new microphysics model for haze and clouds. Our photochemical solver extends computation of the composition above the top of the model up to 1300 km. The radiative transfer is now coupled with microphysics, consisting of the first full radiative coupling of microphysics within a Titan GCM. The model is presented along with its dynamics, thermal structure, and seasonal variations. Despite biases above 10 Pa due to upper boundary limitations, the Titan PCM leads to better modeling of the temperature profiles in the middle atmosphere. Consequently, it is now possible to address some scientific issues about thermal structure in polar regions. Investigations into fall and winter polar phenomena, particularly focusing on thermal structure control and equinoctial circulation reversal, were conducted. This study is linked to the radiative destabilization of the lower polar stratosphere, observed at the end of winter by Cassini radio-occultations. The results confirm a dynamic interplay between haze and gas distributions, which influence the thermal structure
LES EXISTENCES CONTRARIÉES DU DOSSIER MÉDICAL PARTAGÉ (DMP). Retour sur une innovation numériqueau long cours
No full textInternational audienceThis article traces the little-known history of the shared medical record (dossier médical partagé - DMP), seen as an innovation whose trajectory, and especially its extraordinary genesis, warrants analysis. The authors look at the representations, decisions and practices that have governed the DMP’s multiple development projects at national level, from its creation in the 2000s to the recent project to integrate it into the “Mon espace santé” portal, which materialized in 2022. The DMP is characterized by cyclical phases of difficulties, suspensions and relaunching, and, 20 years after its first launch, by the fact that it has not yet fully stabilized or achieved its initial objectives. Paying attention to the multiple temporalities of the innovation process, the analysis brings to light the two major conceptions of healthcare IT that have underpinned the development of the DMP. Italso highlights the importance of the political and institutional context, as well as the instability of the project's governance and the role of several of its actors, which contributed to hampering the translation efforts undertaken.L’article retrace l’histoire encore mal connue du dossier médical partagé (DMP) en analysant les représentations, les décisions et les pratiques qui ont présidé, à l’échelle nationale, à ses multiples projets de développement, depuis sa création au cours des années 2000 jusqu’à son récent projet d’intégration au sein du portail « Mon espace santé », qui s’est concrétisé en 2022. La perspective d’analyse invite à considérer le DMP comme une innovation dont il importe de retracer la trajectoire et, notamment, l’extraordinaire genèse. Le dossier médical partagé a en effet pour caractéristique d’avoir donné lieu à des phases cycliques de difficultés, d’arrêt et de relance, et, 20 ans après son démarrage, de ne pas être totalement stabilisé et de ne pas avoir encore atteint les objectifs fixés initialement. En prêtant attention aux temporalités multiples du processus d’innovation, l’analyse met au jour les deux grandes conceptions de l’informatique de santé qui ont sous-tendu les modalités de développement du DMP. Elle met également en évidence l’importance du contexte politique et institutionnel, ainsi que l’instabilité des modalités de gouvernance du projet et le rôle joué par plusieurs de ses acteurs, qui ont contribué à entraver les efforts de traduction mis en oeuvre
Equivalence scales revisited: Evidence from subjective data
No full textInternational audienceEquivalence scales (ES) are widely used to compare income levels across different households. Yet the commonly used OECD and square-root scales rely on assumptions about household economies of scale that lack robust empirical support. Using responses to the Minimum Income Question (MIQ) from the European Union Statistics on Income and Living Conditions (EU-SILC) survey, we construct subjective ES based on panel data, rather than relying on pooled OLS as in most previous studies, allowing us to track how income needs evolve within households over time instead of comparing different households. The economies of scale in this subjective scale are notably different from those in traditional ES, and these differences have a substantial effect on the levels and distribution of equivalised income. Based on our empirical findings, we propose a simple alternative to conventional ES and illustrate its implications for poverty and inequality, both within and across countries. Our results show that the choice of equivalence scale significantly influences not only the estimated levels of these variables but also country rankings in comparative analyses
La maison, rempart de la société canadienne-française. La résistance culturelle aux politiques sur l’habitation
No full texthttps://www.inventerlegrandparis.fr/link/?id=2839My proposed paper aims to bring the debate on the metropolis into the field of architectural history by touching on the heart of architectural identity: housing. I propose to explore how and why, particularly in the 1930s and 1940s and in Montreal, the Canadian government’s housing programs met resistance from French-Canadian circles, and how this ideological conflict, fanning the flames of tradition, engendered a figure, a mode and an aesthetic of living that still endures today and still differentiates the residential landscapes of the English- and French-speaking portions of Canada’s historic metropolis.Between the wars, Montreal was on the verge of losing its status as Canada’s economic powerhouse to Toronto. Montreal’s population, which at the start of the war exceeded one million, nevertheless outnumbered that of Quebec’s capital by five to one, and a permanent housing shortage threatened the ability of war industries to attract and retain workers. It was at this time that the Government of Canada became actively involved in housing, first with financial incentives for housing construction, then through a Crown corporation that, by 1941, was building tens of thousands of temporary homes across Canada.Quebec, however, displayed a certain reserve in the face of the Federal Government’s initiatives, putting up a rather traditionalist resistance to the new state socialism, particularly in Montreal. By revisiting some of the housing developments of the period, this paper will explore some of the alternatives proposed, as well as their origins, and explore the ideological backgrounds, architectural forms, political discourse and economic formulae that marked the historical course of this resistance.Ma proposition de communication aspire à transporter le débat sur la métropole dans le champ de l’histoire de l’architecture, en touchant au cœur de l’identité architecturale : l’habitation. Je propose d’explorer comment et pourquoi, particulièrement dans les années 1930 et 1940 et à Montréal, les programmes du gouvernement canadien sur l’habitation ont rencontré la résistance des milieux canadiens-français, et comment ce conflit idéologique, attisant l’appel de la tradition, a engendré une figure, un mode et une esthétique de l’habiter qui perdure aujourd’hui et différencie d’ailleurs toujours le paysage résidentiel des portions anglophone et francophone de la métropole historique canadienne.Dans l’entre-deux-guerres, Montréal est en effet en passe de perdre définitivement son statut de métropole économique du Canada, au profit de Toronto. La population montréalaise, qui au début de la guerre dépasse le million d’habitants, surpasse néanmoins de cinq fois celle de la capitale du Québec ; une pénurie de logements y sévit de manière permanente, menaçant la capacité des industries de guerre d’attirer et de retenir adéquatement des travailleurs. C’est l’époque à laquelle le gouvernement du Canada s’engage dans le domaine de l’habitation, d’abord avec des incitatifs financiers à la construction de logements, puis par l’entremise d’une société d’État qui, dès 1941, élèvera des dizaines de milliers de maisons temporaires, aux quatre coins du Canada.Le Québec témoigne toutefois d’une certaine réserve face aux initiatives du gouvernement fédéral, opposant, particulièrement à Montréal, une résistance plutôt traditionnaliste au nouveau socialisme d’État. En revisitant quelques lotissements de l’époque, cette communication explorera quelques-unes des alternatives proposées, ainsi que leur genèse, et en explorant les arrière-plans idéologiques, les formes architecturales, le discours politique et les formules économiques qui ont balisé le parcours historique de cette résistance
Ecophysiological variables retrieval and early stress detection: insights from a synthetic spatial scaling exercise
No full textInternational audienceThe ability to access physiologically driven signals, such as surface temperature, photochemical reflectance index (PRI), and suninduced chlorophyll fluorescence (SIF), through remote sensing (RS) are exciting developments for vegetation studies. Accessing this ecophysiological information requires considering processes operating at scales from the top-of-the-canopy to the photosystems, adding complexity compared to reflectance index-based approaches. To investigate the maturity and knowledge of the growing RS community in this area, COST Action CA17134 SENSECO organized a Spatial Scaling Challenge (SSC). Challenge participants were asked to retrieve four key ecophysiological variables for a field each of maize and wheat from a simulated field campaign: leaf area index (LAI), leaf chlorophyll content (C ab ), maximum carboxylation rate (V cmax,25 ), and non-photochemical quenching (NPQ). The simulated campaign data included hyperspectral optical, thermal and SIF imagery, together with ground sampling of the four variables. Non-parametric methods that combined multiple spectral domains and field measurements were used most often, thereby indirectly performing the top-of-the-canopy to photosystem scaling. LAI and C ab were reliably retrieved in most cases, whereas V cmax,25 and NPQ were less accurately estimated and demanded information ancillary to RS imagery. The factors considered least by participants were the biophysical and physiological canopy vertical profiles, the spatial mismatch between RS sensors, the temporal mismatch between field sampling and RS acquisition, and measurement uncertainty. Furthermore, few participants developed NPQ maps into stress maps or provided a deeper analysis of their parameter retrievals. The SSC shows that, despite advances in statistical and physically based models, the vegetation RS community should improve how field and RS data are integrated and scaled in space and time. We expect this work will guide newcomers and support robust advances in this research field
-robust equivalence of global continuous and local discontinuous approximation, a -stable local projector, and optimal elementwise approximation estimates in
No full textConsider an open bounded connected Lipschitz polygon or polyhedron , a function in the Sobolev space , and a simplicial mesh of . We prove the equivalence of two piecewise -polynomial best approximations of in the seminorm: 1) globally on the whole domain , with the (trace) continuity requirement; 2) locally on each mesh element, without any interelement continuity requirement. The former (global continuous) approximation arises in numerical methods for partial differential equations related to the space, whereas the latter (local discontinuous) approximation is a key quantity in approximation theory. Crucially, we establish -robustness in that the equivalence constant only depends on the mesh shape regularity and the spatial dimension. This improves the recent results of [Found. Comput. Math. {\bf 16} (2016), 723--750] and [Numer. Math. {\bf 135} (2017), 1073--1119], where the equivalence constant was possibly dependent (algebraically or logarithmically) on the underlying polynomial degree. Consequently, we obtain fully - and - (mesh-size- and polynomial-degree-) optimal approximation estimates under the minimal Sobolev regularity only requested separately on each mesh element. These two results immediately follow by our construction of an operator from the infinite-dimensional Sobolev space to its finite-dimensional piecewise polynomial subspace that has simultaneously all the following properties: 1) it is defined over the entire and preserves boundary conditions imposed on a part of the boundary of ; 2) it is defined locally in a neighborhood of each mesh element; 3) the only information about the given function it uses is its elementwise -orthogonal polynomial projection; 4) it is a projector, i.e., it preserves continuous piecewise polynomials; 5) it is locally and -robustly stable in the -seminorm; 6) its approximation property is locally and -robustly equivalent to that of the local discontinuous (elementwise -orthogonal) projection