1,103 research outputs found

    Strong Mixing and Recirculation in the Northwestern Argentine Basin

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    The Atlantic component of the Meridional Overturning Circulation (AMOC) is a key contributor to the global meridional transport of volume, salt, and heat, and thus plays a central role in global climate. As part of ongoing efforts to monitor the intensity and variability of the AMOC in the South Atlantic, hydrographic sections have been regularly occupied since 2009 near the western boundary along a zonal line at 34.5°S. Here this high-quality, high-resolution data set is analyzed to establish the average hydrographic conditions of the northwestern Argentine Basin and the water mass spatial and temporal variability. The water mass analysis also reveals the pathways of the flow in this region, which are further corroborated by full-depth direct velocity measurements. The repeated hydrographic sections capture an extremely rich vertical structure, characterized by seven distinct water mass layers of northern and southern origin, each with unique property signatures. Almost all of these layers exhibit a sharp zonally banded structure, which is indicative of recirculation cells offshore from the western boundary. The circulation at intermediate levels includes a previously undetected recirculation cell confined very close to the western boundary and superimposed on the classical intermediate water pathway beneath the South Atlantic subtropical gyre. The deep level flow is characterized by the Deep Western Boundary Current (DWBC) and a northward recirculation ~500 km east from the slope.Fil: Valla, Daniel. Ministerio de Defensa. Armada Argentina. Servicio de Hidrografía Naval; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Piola, Alberto Ricardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Ministerio de Defensa. Armada Argentina. Servicio de Hidrografía Naval; ArgentinaFil: Meinen, Christopher S.. Atlantic Oceanographic and Meteorological Laboratory; Estados UnidosFil: Campos, Edmo. Universidade de Sao Paulo; Brasi

    Observed Ocean Bottom Temperature Variability at Four Sites in the Northwestern Argentine Basin: Evidence of Decadal Deep/Abyssal Warming Amidst Hourly to Interannual Variability During 2009–2019

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    Consecutive multiyear records of hourly ocean bottom temperature measurements are merged to produce new decade-long time series at four depths ranging from 1,360 to 4,757 m within the northwest Argentine Basin at 34.5°S. Energetic temperature variations are found at a wide range of time scales. All sites exhibit fairly linear warming trends of approximately 0.02–0.04°C per decade over the period 2009–2019, although the trends are only statistically different from zero at the two deepest sites at depths of ~4,500–4,800 m. Near-bottom temperatures from independent conductivity-temperature-depth profiles collected at these same locations every 6–24 months over the same decade show roughly consistent trends. Based on the distribution of spectral energies at the deepest sites and a Monte Carlo-style analysis, sampling at least once per year is necessary to capture the significant warming trends over this decade to within 50% error bars at a 95% confidence limit.Fil: Meinen, Christopher S.. National Ocean And Atmospheric Administration; Estados UnidosFil: Perez, Renellys C.. National Ocean And Atmospheric Administration; Estados UnidosFil: Dong, Shenfu. National Ocean And Atmospheric Administration; Estados UnidosFil: Piola, Alberto Ricardo. Ministerio de Defensa. Armada Argentina. Servicio de HidrografĂ­a Naval; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Campos, Edmo. Universidade de Sao Paulo; Brasil. American University Of Sharjah.; Emiratos Árabes Unido

    Dual-Wavelength Gated oxo-Diels-Alder Photoligation

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    Altres ajuts: Acord transformatiu CRUE-CSICThe control of chemical functionalization with orthogonal light stimuli paves the way toward manipulating materials with unprecedented spatiotemporal resolution. To reach this goal, we herein introduce a photochemical reaction system that enables two-color control of covalent ligation via an oxo-Diels-Alder cycloaddition between two separate light-responsive molecular entities: a UV-activated photocaged diene based on ortho-quinodimethanes and a carbonyl dienophile appended to a diarylethene photoswitch, whose reactivity can be modulated upon illumination with UV and visible light

    Deterrence effects under Twombly: on the costs of increasing pleading standards in litigation

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    We develop a stylized game theoretic model of litigant behavior to study the effects of increased pleading standards on incentives to engage in illegal activity. Such a model is necessary to build intuition about the potential costs associated with the procedures set forth by the U.S. Supreme Court in Bell Atlantic Corp. v. Twombly (550 U.S. 544 [2007]) and Ashcroft v. Iqbal (556 U.S. 662, 684 [2009]), which increase the standard of plausibility that lawsuits must meet before being allowed by a judge to proceed to discovery and trial. We show how increasing pleading standards tends to increase illegal activity, and can increase litigation costs. These negative effects should be accounted for when setting a pleading standard. Our results provide a counterpoint to the U.S. Supreme Court’s argument that increased plausibility requirements will decrease the costs of litigation

    Deterrence effects under Twombly: on the costs of increasing pleading standards in litigation

    Get PDF
    We develop a stylized game theoretic model of litigant behavior to study the effects of increased pleading standards on incentives to engage in illegal activity. Such a model is necessary to build intuition about the potential costs associated with the procedures set forth by the U.S. Supreme Court in Bell Atlantic Corp. v. Twombly (550 U.S. 544 [2007]) and Ashcroft v. Iqbal (556 U.S. 662, 684 [2009]), which increase the standard of plausibility that lawsuits must meet before being allowed by a judge to proceed to discovery and trial. We show how increasing pleading standards tends to increase illegal activity, and can increase litigation costs. These negative effects should be accounted for when setting a pleading standard. Our results provide a counterpoint to the U.S. Supreme Court’s argument that increased plausibility requirements will decrease the costs of litigation
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