La thèse a pour objectif l'étude des plages sableuses enclavées, i.e. contraintes aux extrémités par des caps rocheux, soumises aux vagues et à un cycle de marée morte-eau vive-eau. Une double approche complémentaire liant études numériques et observations et mesures in situ sur un site-atelier a été retenue. Deux modèles déterministes basés sur les différents processus physiques (hydrodynamiques, hydro-sédimentaires et morphodynamiques) en jeu dans la zone littorale et moyennés sur la verticale (2DH) on été sélectionnés. Le code XBeach (Roelvink et al., 2009) utilise un maillage aux différences finies et intègre certaines spécificités tels qu'un modèle de propagation d'un rouleau d'écume ("roller"), un modèle de génération d'ondes longues et un modèle de développement d'un contre-courant de retour "undertow". Le code TELEMAC (Hervouet, 2007) utilise un maillage aux éléments finis. Pour le site-atelier, les plages enclavées adjacentes de La Palue et de Lostmarc'h en Presqu'île de Crozon (Finistère) ont été choisies pour leur bathymétrie complexe (présence de chenaux de baïne et d'un saillant) et leur géométrie complexe (caps rocheux de longueurs diverses, îlot). Une année d'observations et de mesures in situ (levés topographiques, pose de courantomètres ADV) a été entreprise entre le mois de septembre 2014 et le mois de septembre 2015, par diverses conditions météorologiques.Dans un premier temps, la dynamique globale des plages enclavées, représentées schématiquement par une échancrure rectangulaire, a été appréhendée. En particulier, la genèse d'une barre de déferlement en zone subtidale sous l'influence des dimensions de l'échancrure rocheuse, d'un cycle de marée morte-eau vive-eau et de houles énergétiques a été illustrée à travers plusieurs séries de simulations numériques à l'aide du code XBeach.Dans un deuxième temps, la modélisation hydrodynamique des courants sur les plages de La Palue et de Lostmarc'h a été effectuée, avec l'objectif d'étudier l'influence des caractéristiques des houles (hauteur, période et direction) et de celles de l'échancrure rocheuse (longueur des caps, espacement des caps, inclinaison des pointes) sur la prédiction des courants. Une ouverture sur la modélisation aux éléments finis (TELEMAC) en comparaison à celle aux différences finies (XBeach) a été présentée. Le code XBeach a été validé sur le plan hydrodynamique grâce aux mesures in situ d'une campagne de terrain réalisée en janvier 2015. Une étude numérique hydro-sédimentaire sur une lunaison complète (du 01 septembre 2015 au 29 septembre 2015) a alors été entreprise à l'aide du code XBeach, afin d'étudier l'intensité et la direction des flux sédimentaires instantanés et résiduels au gré des différents climats de houle et de marée, et selon les différents secteurs typologiques des plages de La Palue et de Lotsmarc'h. Cela a permis de mettre en évidence les particularités de la dynamique des plages enclavées par rapport aux plages ouvertes "quasi-infinies", tels que le phénomène de "contournement de cap", mais aussi les similitudes. Les résultats du code XBeach, pour différentes configurations du modèle, ont par ailleurs été comparés aux levés topographiques réalisés au cours du mois de septembre 2015.Dans un troisième temps, après une analyse statistique approfondie des climats de houle au large des plages de La Palue et de Lostmarc'h sur une période de 7 ans, l'impact morphodynamique de tempêtes extrêmes (houles décennale et cinquentennale) conjugué à celui de la hausse du niveau marin induit par le changement climatique, a été estimé sous la forme d'une étude numérique à l'aide du code XBeach sur un profil transversal au sud de la plage de La Palue / In this thesis, waves and neap-spring tide action on sandy embayed beaches constrained by rocky headlands is studied. A complementary approach combining numerical modeling and in situ measurements is used. Two deterministic model based on major physical processes (hydrodynamics, hydro-sedimentary and morphodynamics) present in the coastal zone and averaged over the water height (2DH) have been selected. XBeach (Roelvink et al., 2009) employs a finite difference scheme and incorporates some specific processes such as a roller, wave groups and the associated bound long wave and a undertow. TELEMAC (Hervouet, 2007) is a finite element scheme. Nearby sandy embayed beaches of La Palue and Lostmarc'h (Crozon Peninsula, Finistère) have been chosen for their complex bathymetry (rip channels, tombolo) and geometry (headlands, small island). One year of in situ measurements (topographical surveys, ADV velocimeters) between septembre 2014 and september 2015 has been undertaken, with different waves and tide climates.Firstly, the overall dynamics of embayed beaches built schematically in the form of a rectangular indentation has been caught. Especially, subtidal sandbar formation under the influence of waves, neap-spring tide and rocky headlands has been studied through several sets of numerical simulations.Secondly, hydrodynamic modelling on the embayed beaches of La Palue and Lostmarc'h has been made with the aim of study influence of waves characteristics (height, period and direction) and indentation's ones (headlands length, spacing between headlands, headlands inclination) on the prediction of currents. A simulation using finite element scheme (TELEMAC) has been achieved and compared to those using finite difference scheme (XBeach). XBeach currents predictions at two locations on the beaches of La Palue and Lostmarc'h over the period from the 21st January 2015 to the 23rd January 2015 have been compared to in situ measurements to validate the model. Whereupon, a numerical hydro-sedimentary simulation (using XBeach) over a full lunation from the 1st September 2015 to the 29th September 2015 has been undertaken on these two beaches, with the aim of study the intensity and direction of sediment flux (instantaneous and residual) for various waves and tide climates and for different morphological areas. This work has helped to highlight the dynamics features of embayed beaches compared to open beaches ones, such as headland sand bypassing, but also similarities. Moreover, XBeach morphodynamics predictions have been compared to in situ measurements for different model setup.Thirdly, after an in-depth statistical analysis of wave climates over a 7 year period offshore of La Palue and Lostmarc'h beaches, the morphodynamic impact of extreme storm waves (ten-yearly and fifty-yearly) combined to a sea level rise induced by climatic change on a cross-shore bottom profile south of La Palue has been estimated through a numerical study (using XBeach)

The possibility to earn a living and support a family independently is still a utopia for many women all around the world. Many organizations are constantly fighting for awareness of these issues and strive for an improvement in women’s economic equality. One of these organizations is the Committee on the Elimination of Discrimination against Women (CEDAW) which in its preamble acknowledges that "discrimination violates the principles of equality of rights and respect for human dignity".By the tenth anniversary of the CEDAW, almost one hundred nations have agreed to be bound by its provision. Some governments have achieved their goals by replacing discriminatory laws and policies in order to guarantee gender equality. Others have even gone the extra mile by promoting legislation which in turn would make it easier for women to be able to develop their careers. For instance, some have provided longer maternity leave, and in a few exceptional cases, some others gave the possibility of joint parental leave, creating a co-responsibility between men and women. Nevertheless, some governments have not done enough to balance the gender gap. Some even keep discriminatory laws on the books despite having come to powerlifting the flag of social justice and gender equality. This has been the case of many of the so-called “Pink Tide governments” that ruled in the majority of South America during the first two decades of the 21st century. Despite the left turn of these governments, women in the region are still exposed to segregation and jobs with lower status or a lower payment. This paper focuses on this particular period of South American political history, with a focus on the government policies issued to fight the increasing gender gap on women's economic participation and opportunities. In order to account for the actions taken by these governments towards gender equality policies, we will analyze the maternity and parental leave laws implemented during this period, as we understand that women’s social and economic rights are closely related to their status and conditions at work. Finally, we argue that in this case, the color pink has not been representing women in Latin America.

The terdiurnal tide (TDT) in the mesosphere and lower thermosphere has been simulated with a 3D mechanistic circulation model of the middle atmosphere. The tidal temperature amplitude shows a clear seasonal cycle with peaks in the midlatitudes and near the equator at equinox. Under solstice conditions maximum amplitudes occur at 10° in the summer hemisphere and at 30-40° latitude in the winter hemisphere. The vertical wavelengths are large at midlatitudes and small at the equator with about 15 km. These characteristics are compared with SABER/TIMED satellite data from 2002-2009. Especially for temperature amplitudes good agreement is visible. At 90 km, comparison of the zonal wind TDT with radar observations from the literature also shows that the model realistically simulates the seasonal cycle of the TDT. / Die achtstündige Gezeit (TDT) in der Mesosphäre und unteren Thermosphäre wurde mit einem 3D mechanistischen Zirkulationsmodell der mittleren Atmosphäre modelliert. Die Amplitude der achtstündigen Gezeit in der Temperatur zeigt dabei eine klare saisonale Variabilität mit Maxima im Bereich der mittleren Breiten und des Äquators während der Äquinoktien. Die vertikale Wellenlänge ist in den mittleren Breiten groß und am Äquator mit ca. 15 km klein. Diese Strukturen werden mit SABER/TIMED Satellitenmessungen der Jahre 2002-2009 verglichen. Vor allem für die Amplituden in der Temperatur ist eine gute Übereinstimmung zu erkennen. Ein Vergleich der achtstündigen Gezeit im Zonalwind in 90 km Höhe mit Radarmessungen aus der Literatur zeigt, dass das Modell den Jahresgang realistisch simuliert.

While the diurnal, semidiurnal and terdiurnal tides in the mesosphere / lower thermosphere (MLT) have been observed from the ground and from satellites, the quarterdiurnal tide (QDT), with a period of 6 hours, has been investigated on a few occasions only. Therefore, meteor radar observations of horizontal winds in the MLT near 90 km at Collm (51°N, 13°E) and Obninsk (55°N, 37°E) have been used to analyse the seasonal variability of the QDT at middle latitudes. At both sites the zonal amplitudes show a clear maximum in winter and another one during spring. The meridional amplitudes are weaker, but show a similar seasonal cycle. Generally amplitudes are not large and maximise at 3.5 m/s for the zonal amplitude on a climatological mean. Amplitudes and phases, the latter expressed in local time, at Collm and Obninsk are similar, indicating that most of the observed 6-hour oscillation at higher midlatitudes is due to the migrating QDT. Obninsk amplitudes show an interdecadal variation with smaller values during the 1990s and larger ones during the 2000s. / Während die ganztägigen, halbtägigen und dritteltägigen Gezeiten in der Mesosphäre und unteren Thermosphäre (mesosphere/lower thermosphere, MLT) vergleichsweise häufig durch bodengebundene und Satellitenmessungen untersucht wurden, gilt dies nur sehr eingeschränkt für die vierteltägigen Gezeiten (quarterdiurnal tides, QDT). Daher werden hier Radarmessungen des horizontalen Windes über Collm (51°N, 13°E) und Obninsk (55°N, 37°E) bei 90 km Höhe herangezogen, um den mittleren Jahresgang der QDT in mittleren Breiten zu analysieren. Es zeigt sich, dass an beiden Messstationen ein Maximum der Amplituden im Zonalwind auftritt, begleitet von einem weiteren im Frühjahr. Die Amplituden sind nicht sehr groß, und betragen für den Zonalwind 3-4 m/s im langzeitigen Mittel im Winter. Die Amplituden im meridionalen Wind sind etwas geringer, zeigen aber einen ähnlichen Jahresgang. Amplituden und Phasen, letztere ausgedrückt in lokaler Zeit, sind über Collm und Obninsk ähnlich, was auf einen bedeutenden Anteil der migrierenden QDT hinweist. Die Amplituden über Obninsk weisen eine interdekadische Variation auf, mit geringeren Amplituden in den 1990ern und größeren nach den Jahr 2000.

We use the middle and upper atmosphere model (MUAM) to analyze forcing mechanisms of the terdiurnal tide (TDT) in the middle atmosphere, namely solar heating and nonlinear wave-wave interactions. First, we present model amplitudes of the TDT during January conditions as a validation and for reference. By switching off single forcings for wavenumber 3 in different model runs we are able to separate the solar and nonlinear forcing contribution. The simulations suggest that solar forcing is the major driver for TDT at low latitudes while nonlinear interactions become more important at middle and high latitude, especially in the winter hemisphere. Additionally we observe increased TDT amplitudes for purely solar driven TDTs without nonlinear forcing in some regions which may be owing to destructive interferences. / Wir nutzen das Modell für die mittlere und obere Atmosphäre (MUAM), um die Anregungsmechanismen der dritteltägigen Gezeiten, solare Erwärmung und Wechselwirkungen zwischen Wellen, zu analysieren. Zunächst präsentieren wir die modellierten Amplituden der dritteltägigen Gezeiten für Januarbedingungen. Dies dient einerseits der Validierung und andererseits als Referenz. Indem die Wellenzahl 3 in den verschiedenen Anregungstermen in einzelnen Läufen ausgeschalten wird, lassen sich die jeweiligen Beiträge aus solarer und nichtlinearer Anregung separieren. Aus den Simulationen lässt sich ableiten, dass solare Erwärmung den Hauptanteil in niedrigen Breiten bildet, während nichtlineare Wechselwirkungen in mittleren und hohen Breiten immer wichtiger werden, vor allem auf der Winterhemisphäre. Zudem beobachten wir verstärkte Amplituden der dritteltägigen Gezeiten bei ausschließlich solarer Anregung ohne nichtlinearen Anteil, was an destruktiver Überlagerung der Antriebsterme liegen kann.

Global Positioning System radio occultation measurements by the FORMOsa SATellite mission-3/Constellation Observing System for Meteorology, Ionosphere and Climate satellites were used to analyse the behaviour of the signature of the terdiurnal tide in sporadic E (ES) layers at midlatitudes (43°N – 63°N). According to theory, the occurrence of ES is expected when the vertical zonal wind shear, which is mainly owing to solar tides, is negative. 4-year means, based on 3-monthly running mean zonal means from December 2006 - November 2010, were constructed for the terdiurnal oscillation in the occurrence frequency of ES. Comparison of the results with VHF meteor radar observations of the terdiurnal tide and the 8-hr oscillation in the vertical zonal wind shear at Collm, Germany (51.3°N, 13°E) shows a clear correspondence between the 8-hr Es and wind shear signature. / Radiookultationsmessungen auf der Basis von GPS-Messungen der FORMOsa SATellite mission-3/Constellation Observing System for Meteorology, Ionosphere and Climate-Satelliten wurden verwendet, um die Signatur der 8-stündigen Gezeiten in den Auftrittsraten von sporadischen E (Es)-Schichten zu analysieren. Nach der allgemein anerkannten Windscherungstheorie treten Es-Schichten im Bereich negativer vertikaler Windscherung auf, welche in der unteren Thermosphäre hauptsächlich durch solare Gezeiten hervorgerufen werden. Speziell werden hier 4-jährige Mittelwerte saisonal gemittelter Auftrittsraten untersucht um die 8-stündige Signatur zu finden. Ein Vergleich mit Radarmessungen des Windes über Collm zeigt, dass die saisonale und tägliche Variabilität der 8-stündigen Komponente der Es-Raten sehr gut mit derjenigen der gemessenen Windscherung übereinstimmt.

The following study provides a critical interpretation of the ten years’ administration of Rafael Correa in Ecuador. The main goal is to comprehend to which extent structural transformations were achieved during his period in power and what lessons can be drawn in order to conceptualize strategies for the complete emancipation of Latin America.

The West Florida Shelf (WFS) is one of the largest and most diversely-used continental shelf/slope systems in the world. The presence of paleoshorelines and scarped hardbottom outcrops (up to 4 m in relief) along the inner shelf (10-30 m depth) provide important habitat for a variety of infaunal, epifaunal, and fish assemblages that contribute to the productivity of the region. This dissertation will present a comprehensive overview of the geological, physical, and chemical settings of the inner West Florida Shelf, with particular focus on biological and ecological community dynamics of epibenthic macroinvertebrates, algae, and fish assemblages. Baseline and comparative data sets are presented in the form of historic and modern species lists, with focus on seasonal and intra-annual variations. Quantitative effects of disturbances (e.g., hurricanes, thermal stresses, and red tides) and subsequent recovery rates are discussed as they periodically perturb inner-shelf systems and can have significant effects on community structure. Benefits of and recommendations for using artificial reefs as restoration tools along the inner shelf, as mitigation for future disturbances, are presented.

No description available.

Recently, a highly resolved, finite element mesh was developed for the purpose of performing hydrodynamic calculations in the Western North Atlantic Tidal (WNAT) model domain. The WNAT model domain consists of the Gulf of Mexico, the Caribbean Sea, and the entire portion of the North Atlantic Ocean found west of the 60° W meridian. This high resolution mesh (333K) employs 332,582 computational nodes and 647,018 triangular elements to provide approximately 1.0 to 25 km node spacing. In the previous work, the 333K mesh was applied in a Localized Truncation Error Analysis (LTEA) to produce nodal density requirements for the WNAT model domain. The goal of the work herein is to use these LTEA-based element sizing guidelines in order to obtain a more optimal finite element mesh for the WNAT model domain, where optimal refers to minimizing nodes (to enhance computational efficiency) while maintaining model accuracy, through an automated procedure. Initially, three finite element meshes are constructed: 95K, 60K, and 53K. The 95K mesh consists of 95,062 computational nodes and 182,941 triangular elements providing about 0.5 to 120 km node spacing. The 60K mesh contains 60,487 computational nodes and 108,987 triangular elements. It has roughly 0.5 to 185 km node spacing. The 53K mesh includes 52,774 computational nodes and 98,365 triangular elements. This is a particularly coarse mesh, consisting of approximately 0.5 to 160 km node spacing. It is important to note that these three finite element meshes were produced automatically, with each employing the bathymetry and coastline (of various levels of resolution) of the 333K mesh, thereby enabling progress towards an optimal finite element mesh. Tidal simulations are then performed for the WNAT model domain by solving the shallow water equations in a time marching manner for the deviation from mean sea level and depth-integrated velocities at each computational node of the different finite element meshes. In order to verify the model output and compare the performance of the various finite element mesh applications, historical tidal constituent data from 150 tidal stations located within the WNAT model domain are collected and examined. These historical harmonic data are applied in two types of comparative analyses to evaluate the accuracy of the simulation results. First, qualitative comparisons are based on visual sense by utilizing plots of resynthesized model output and historical tidal constituents. Second, quantitative comparisons are performed via a statistical analysis of the errors between model response and historical data. The latter method elicits average phase errors and goodness of average amplitude fits in terms of numerical values, thus providing a quantifiable way to present model error. The error analysis establishes the 53K finite element mesh as optimal when compared to the 333K, 95K, and 60K meshes. However, its required time step of less than ten seconds constrains its application. Therefore, the 53K mesh is manually edited to uphold accurate simulation results and to produce a more computationally efficient mesh, by increasing its time step, so that it can be applied to forecast tide and storm surge in the Western North Atlantic Ocean on a real-time basis.