Future Projections of EURO-CORDEX Raw and Bias-Corrected Daily Maximum Wind Speeds Over Scandinavia

Postponed access: the file will be available after 2023-08-21Twenty historical and future Coordinated Regional Climate Downscaling Experiment ensemble for Europe simulations are bias corrected to investigate the future changes in the daily maximum wind speed over Scandinavia. We use quantile mapping to adjust the wind for the historical period (1985–2014) and quantile delta mapping for two future periods (2041–2070, 2071–2100, RCP8.5) with the 3-km spatial resolution NORA3 hindcast as the reference data set. Decomposing the variance, we find that most of the inter-model spread in the bias and the response to climate change is due to the regional climate model over land and mainly to the general climate model over sea. On average, the mean daily maximum wind speed is projected to increase everywhere except along the western coast of Norway and Denmark. In summer, we see an opposite sign over Sweden and Finland. The Norwegian Sea experiences weaker mean and high wind whereas the Baltic Sea experiences a strengthening. Bias correction influences the amplitude of the response, not the response pattern. Wind speed distributions can have different shapes in the future, with, for example, a flattening of the distribution off the coast of Norway with more frequent weak and very strong winds. Apart from a few locations in Norway, we find an increase in the number of days in the local highest historical wind category. Overall, summer exhibits opposite signals compared to the three other seasons. At country scale, the sign of the change in the mean and 98th percentile varies greatly depending on the region and among the simulations, especially for Norway.publishedVersio

Rôle du déferlement des ondes de Rossby dans la variabilité climatique aux latitudes tempérées

L'objectif de cette thèse a été d'analyser la dynamique de l'interaction entre les ondes baroclines (ou rail des dépressions) et la variabilité basse fréquence de l'atmosphère aux moyennes latitudes. Deux approches distinctes ont été suivies pour étudier le rôle des déferlements d'ondes baroclines sur les courants-jets, l'une reposant sur les données réanalysées et l'autre sur des simulations numériques. La première partie de la thèse a plus précisément consisté à étudier le lien entre les déferlements d'ondes de Rossby et les quatre régimes de temps sur l'Atlantique Nord en hiver en utilisant les réanalyses ERA40. Le calcul des fréquences d'occurrence des déferlements d'ondes a montré que ceux-ci tendent généralement à renforcer les régimes sauf le blocage scandinave qui est détruit par du déferlement cyclonique au sud du Groenland. Ensuite, les précurseurs des transitions entre régimes de temps ont été identifiés. Le premier précurseur est relié à la propagation linéaire d'anomalies basse fréquence (période supérieure à 10 jours). Ce précurseur n'est pas systématique mais il survient durant la transition du régime zonal vers le blocage environ une semaine avant ce dernier où il prend la forme d'un train d'ondes quasi-stationnaire excité par des anomalies convectives dans l'Atlantique subtropical. Le second précurseur plus systématique intervient au niveau des interactions non-linéaires entre les tourbillons transitoires haute et basse fréquences et a pu être relié aux déferlements d'ondes. La formation et la destruction du blocage scandinave ont ensuite été plus particulièrement étudiées en analysant respectivement les transitions préférentielles du régime zonal au blocage et du blocage vers l'anticyclone groenlandais en lien avec les dépressions de surface et les déferlements d'ondes. Les dépressions de surface atteignent les mêmes intensités pendant la formation et la destruction du blocage mais ne suivent pas les mêmes trajectoires. Pendant la formation du blocage, les dépressions de surface ont des trajectoires rectilignes se dirigeant vers le nord de la Scandinavie et sont liées à un déferlement anticyclonique. Pendant la destruction du blocage, les trajectoires des dépressions de surface sont courbées sur l'Atlantique Nord en direction du Groenland et sont reliées à du déferlement cyclonique qui favorise ainsi l'apparition de l'anticyclone groenlandais. Notre analyse suggère que cette différence de comportement provient de la forme de l'écoulement basse fréquence qui n'est pas le même pendant la formation et la destruction du blocage et qui favorise un certain type de déferlement plutôt qu'un autre. Dans la seconde partie de la thèse, nous avons analysé le lien entre les températures de surface de la mer (SSTs) et le comportement du rail des dépressions avec le modèle de circulation générale de l'atmosphère Arpège-Climat en mode aquaplanète pour mieux comprendre les téléconnexions telles que l'Oscillation Arctique et/ou l'Oscillation Nord-Atlantique d'un point de vue idéalisé. Pour cela, nous avons fait une étude de sensibilité de la variabilité de l' "eddy-driven" jet à différents profils méridiens de SSTs fixes dans le temps. L'intensité de l'activité du rail des dépressions et de l' "eddy-driven" jet, qui tend à augmenter pour un front de SST d'intensité plus élevée, de largeur plus grande ou localisé plus proche du jet subtropical, peut s'interpréter aisément par une augmentation de la baroclinie dans chaque cas. La position de l' "eddy-driven" jet dépend plus des propriétés des déferlements d'ondes. En effet, sa position systématique du côté polaire du front de SST peut s'expliquer par des déferlements anticycloniques plus fréquents que les déferlements cycloniques et cette asymétrie s'accentue lorsque le front de SST est déplacé vers le pôle. Enfin, un jet subtropical plus intense élargit la zone de propagation des ondes du côté équatorial du front ce qui pousse le déferlement anticyclonique à se produire plus près de l'équateur et donc à rapprocher l' "eddy-driven" jet du jet subtropical. D'autre part, nous avons mis en évidence que le mode dominant de variabilité de l' "eddy-driven" jet varie en fonction de la latitude du front de SST. Près de l'équateur, la variabilité dominante est une fluctuation latitudinale de l' "eddy-driven" jet. Mais plus le front de SST est vers le pôle, plus le mode de variabilité de l' "eddy-driven" jet tend à passer d'un régime de fluctuation latitudinale de sa position à un régime de pulsation de son amplitude. Ce résultat pourrait expliquer pourquoi dans les réanalyses ERA40, le mode dominant de variabilité du jet Pacifique Sud est associé à un régime de pulsation alors que celui de l'Indien Sud à un régime de fluctuation latitudinale

Dynamical drivers of Greenland blocking in climate models

Blocking over Greenland is known to lead to strong surface impacts, such as ice sheet melting, and a change in its future frequency can have important consequences. However, as previous studies demonstrated, climate models underestimate the blocking frequency for the historical period. Even though some improvements have recently been made, the reasons for the model biases are still unclear. This study investigates whether models with realistic Greenland blocking frequency in winter have a correct representation of its dynamical drivers, most importantly, cyclonic wave breaking (CWB). Because blocking is a rare event and its representation is model-dependent, we use a multi-model large ensemble. We focus on two models that show typical Greenland blocking features, namely a ridge over Greenland and an equatorward-shifted jet over the North Atlantic. ECHAM6.3-LR has the best representation of CWB of the models investigated but only the second best representation of Greenland blocking frequency, which is underestimated by a factor of 2. While MIROC5 has the most realistic Greenland blocking frequency, it also has the largest (negative) CWB frequency bias, suggesting that another mechanism leads to blocking in this model. Composites over Greenland blocking days show that the present and future experiments of each model are very similar to each other in both amplitude and pattern and that there is no significant change in Greenland blocking frequency in the future. However, these projected changes in blocking frequency are highly uncertain as long as the mechanisms leading to blocking formation and maintenance in models remain poorly understood.publishedVersio

Control of Barents Sea wintertime cyclone variability by large-scale atmospheric flow

Extratropical cyclones transport heat and moisture into the Arctic, which can promote surface warming and sea ice melt. We investigate wintertime cyclone variability in the Barents Sea region to understand what controls the impacts, frequency, and path of cyclones at high latitudes. Large‐scale atmospheric conditions are found to be key, with the strongest surface warming from cyclones originating south of 60°N in the North Atlantic and steered northeastward by the upper‐level flow. Atmospheric conditions also control cyclone variability in the Barents proper: Months with many cyclones are characterized by an absence of high‐latitude blocking and enhanced local baroclinicity, due to the presence of strong upper‐level winds and a southwest‐northeast tilted jet stream more than changes in sea ice. This study confirms that Arctic cyclones exhibit large interannual variability, and accounting for this variability reveals that trends in Barents cyclone frequency are not robust over the 1979–2018 period.publishedVersio

Analyzing Ideological Communities in Congressional Voting Networks

We here study the behavior of political party members aiming at identifying how ideological communities are created and evolve over time in diverse (fragmented and non-fragmented) party systems. Using public voting data of both Brazil and the US, we propose a methodology to identify and characterize ideological communities, their member polarization, and how such communities evolve over time, covering a 15-year period. Our results reveal very distinct patterns across the two case studies, in terms of both structural and dynamic properties

Systematic analysis of COVID-19 infection and symptoms in a systemic lupus erythematosus population: correlation with disease characteristics, hydroxychloroquine use and immunosuppressive treatments.

peer reviewe

Discovery of new rheumatoid arthritis biomarkers using the surface-enhanced laser desorption/ionization time-of-flight mass spectrometry ProteinChip approach.

peer reviewedOBJECTIVE: To identify serum protein biomarkers specific for rheumatoid arthritis (RA), using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) technology. METHODS: A total of 103 serum samples from patients and healthy controls were analyzed. Thirty-four of the patients had a diagnosis of RA, based on the American College of Rheumatology criteria. The inflammation control group comprised 20 patients with psoriatic arthritis (PsA), 9 with asthma, and 10 with Crohn's disease. The noninflammation control group comprised 14 patients with knee osteoarthritis and 16 healthy control subjects. Serum protein profiles were obtained by SELDI-TOF-MS and compared in order to identify new biomarkers specific for RA. Data were analyzed by a machine learning algorithm called decision tree boosting, according to different preprocessing steps. RESULTS: The most discriminative mass/charge (m/z) values serving as potential biomarkers for RA were identified on arrays for both patients with RA versus controls and patients with RA versus patients with PsA. From among several candidates, the following peaks were highlighted: m/z values of 2,924 (RA versus controls on H4 arrays), 10,832 and 11,632 (RA versus controls on CM10 arrays), 4,824 (RA versus PsA on H4 arrays), and 4,666 (RA versus PsA on CM10 arrays). Positive results of proteomic analysis were associated with positive results of the anti-cyclic citrullinated peptide test. Our observations suggested that the 10,832 peak could represent myeloid-related protein 8. CONCLUSION: SELDI-TOF-MS technology allows rapid analysis of many serum samples, and use of decision tree boosting analysis as the main statistical method allowed us to propose a pattern of protein peaks specific for RA

Occupational, academic, and personal determinants of wellbeing and psychological distress in residents: results of a survey in Lyon, France

IntroductionThe mental health of residents is a growing significant concern, particularly with respect to hospital and university training conditions. Our goal was to assess the professional, academic, and psychological determinants of the mental health status of all residents of the academy of Lyon, France.Materials and methodsThe Health Barometer of Lyon Subdivision Residents (BASIL) is an initiative which consists in proposing a recurrent online survey to all residents in medicine, pharmacy, and dentistry, belonging to the Lyon subdivision. The first of these surveys was conducted from May to July 2022. Participants should complete a series of validated questionnaires, including the Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS), and the Kessler Psychological Distress Scale (K6), respectively, and ad-hoc questions assessing their global health and hospital and academic working conditions. A Directed Acyclic Graph (DAG) analysis was conducted prior to multivariable analyses, to explore the determinants associated with low wellbeing (WEMWBS <43) and high psychological distress (K6 ≥ 13).ResultsA total of 904 residents (response rate: 46.7%) participated in the survey. A low level of wellbeing was observed in 23% of participants, and was significantly associated to job strain (OR = 2.18; 95%CI = [1.32–3.60]), low social support (OR = 3.13; 95%CI = [2.05–4.78]) and the experience of very poor university teaching (OR = 2.51; 95%CI = [1.29–4.91]). A high level of psychological distress was identified for 13% of participants, and associated with low social support (OR = 2.41; 95%CI = [1.48–3.93]) and the experience of very poor university teaching (OR = 2.89, 95%CI = [1.16–7.21]).ConclusionHospital working conditions, social support, and the perception of teaching quality, were three major determinants of wellbeing and psychological distress among health profession residents. Demographic determinants, personal life and lifestyle habits were also associated. This supports a multilevel action in prevention programs aiming to enhance wellbeing and reduce mental distress in this specific population and local organizational specificities

Intercomparison of NO2, O4, O3 and HCHO slant column measurements by MAX-DOAS and zenith-sky UV¿visible spectrometers during CINDI-2

40 pags., 22 figs., 13 tabs.In September 2016, 36 spectrometers from 24 institutes measured a number of key atmospheric pollutants for a period of 17¿d during the Second Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI-2) that took place at Cabauw, the Netherlands (51.97¿¿N, 4.93¿¿E). We report on the outcome of the formal semi-blind intercomparison exercise, which was held under the umbrella of the Network for the Detection of Atmospheric Composition Change (NDACC) and the European Space Agency (ESA). The three major goals of CINDI-2 were (1) to characterise and better understand the differences between a large number of multi-axis differential optical absorption spectroscopy (MAX-DOAS) and zenith-sky DOAS instruments and analysis methods, (2) to define a robust methodology for performance assessment of all participating instruments, and (3) to contribute to a harmonisation of the measurement settings and retrieval methods. This, in turn, creates the capability to produce consistent high-quality ground-based data sets, which are an essential requirement to generate reliable long-term measurement time series suitable for trend analysis and satellite data validation. The data products investigated during the semi-blind intercomparison are slant columns of nitrogen dioxide (NO2), the oxygen collision complex (O4) and ozone (O3) measured in the UV and visible wavelength region, formaldehyde (HCHO) in the UV spectral region, and NO2 in an additional (smaller) wavelength range in the visible region. The campaign design and implementation processes are discussed in detail including the measurement protocol, calibration procedures and slant column retrieval settings. Strong emphasis was put on the careful alignment and synchronisation of the measurement systems, resulting in a unique set of measurements made under highly comparable air mass conditions. The CINDI-2 data sets were investigated using a regression analysis of the slant columns measured by each instrument and for each of the target data products. The slope and intercept of the regression analysis respectively quantify the mean systematic bias and offset of the individual data sets against the selected reference (which is obtained from the median of either all data sets or a subset), and the rms error provides an estimate of the measurement noise or dispersion. These three criteria are examined and for each of the parameters and each of the data products, performance thresholds are set and applied to all the measurements. The approach presented here has been developed based on heritage from previous intercomparison exercises. It introduces a quantitative assessment of the consistency between all the participating instruments for the MAX-DOAS and zenith-sky DOAS techniques.CINDI-2 received funding from the Netherlands Space Office (NSO). Funding for this study was provided by ESA through the CINDI-2 (ESA contract no. 4000118533/16/ISbo) and FRM4DOAS (ESA contract no. 4000118181/16/I-EF) projects and partly within the EU 7th Framework Programme QA4ECV project (grant agreement no. 607405). The BOKU MAX-DOAS instrument was funded and the participation of Stefan F. Schreier was supported by the Austrian Science Fund (FWF): I 2296-N29. The participation of the University of Toronto team was supported by the Canadian Space Agency (through the AVATARS project) and the Natural Sciences and Engineering Research Council (through the PAHA project). The instrument was primarily funded by the Canada Foundation for Innovation and is usually operated at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change (CANDAC). Funding for CISC was provided by the UVAS (“Ultraviolet and Visible Atmospheric Sounder”) projects SEOSAT/INGENIO, ESP2015-71299- R, MINECO-FEDER and UE. The activities of the IUP-Heidelberg were supported by the DFG project RAPSODI (grant no. PL 193/17-1). SAOZ and Mini-SAOZ instruments are supported by the Centre National de la Recherche Scientifique (CNRS) and the Centre National d’Etudes Spatiales (CNES). INTA recognises support from the National funding projects HELADO (CTM2013-41311-P) and AVATAR (CGL2014-55230-R). AMOIAP recognises support from the Russian Science Foundation (grant no. 16-17-10275) and the Russian Foundation for Basic Research (grant nos. 16-05- 01062 and 18-35-00682). Ka L. Chan received transnational access funding from ACTRIS-2 (H2020 grant agreement no. 654109). Rainer Volkamer recognises funding from NASA’s Atmospheric Composition Program (NASA-16-NUP2016-0001) and the US National Science Foundation (award AGS-1620530). Henning Finkenzeller is the recipient of a NASA graduate fellowship. Mihalis Vrekoussis recognises support from the University of Bremen and the DFG Research Center/Cluster of Excellence “The Ocean in the Earth System-MARUM”. Financial support through the University of Bremen Institutional Strategy in the framework of the DFG Excellence Initiative is gratefully appreciated for Anja Schönhardt. Pandora instrument deployment was supported by Luftblick through the ESA Pandonia Project and NASA Pandora Project at the Goddard Space Flight Center under NASA Headquarters’ Tropospheric Composition Program. The article processing charges for this open-access publication were covered by BK Scientific