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mfontela/ArgentineBasin: Tracer trends in Argentine Basin Water Masses
No full textCode and data to reproduce the article "Anthropogenic CO2 and ocean acidification in Argentine Basin Water Masses over almost five decades of observations" by Marcos Fontela et al.
When used, please cite this doi and/or the original work:
Marcos Fontela, Antón Velo, Miguel Gilcoto, Fiz F. Pérez. Anthropogenic CO2 and ocean acidification in Argentine Basin Water Masses over almost five decades of observations. 2021. Science of the Total Environment. Volume 779, 20 July 2021, 146570.
ABSTRACT
The chemical conditions of the Argentine Basin (western South Atlantic Ocean) water masses are evaluated with measurements from eleven hydrographic cruises to detect and quantify climate change anthropogenic and natural stressors in the ocean carbon system. The database covers almost half-century (1972-2019), a time-span where the mean annual atmospheric carbon dioxide concentration (CO2atm) increased from 3257 to 40811 parts per million of volume (ppm). This increase of atmospheric CO2 (834 ppm, the 64% of the total anthropogenic signal in the atmosphere) leads to an increase in anthropogenic carbon (Cant) across all the water column and the consequent ocean acidification: a decrease in excess carbonate that is unequivocal in the upper (South Atlantic Central Water, SACW) and intermediate water masses (Sub Antarctic Mode Water, SAMW and Antarctic Intermediate Water, AAIW). For each additional ppm in CO2atm the water masses SACW, SAMW and AAIW lose excess carbonate at a rate of 0.398±0.04, 0.476±0.056 and 0.232±0.03 μmol·kg-1·ppm-1 respectively. Modal and intermediate water masses in the Argentine Basin are very sensitive to carbon increases due low buffering capacity. The large rate of AAIW acidification is the synergic effect of carbon uptake combined with deoxygenation and increased remineralization of organic matter. If CO2 emissions follows the path of business-as-usual emissions (SSP 5.85), SACW would become undersaturated with respect to aragonite at the end of the century. The undersaturation in AAIW is virtually unavoidable
Anthropogenic CO2 and ocean acidification in Argentine Basin Water Masses over almost five decades of observations
Full text link9 pages, 5 figures, 2 tables.-- Under a Creative Commons licenseThe chemical conditions of the Argentine Basin (western South Atlantic Ocean) water masses are evaluated with measurements from eleven hydrographic cruises to detect and quantify anthropogenic and natural stressors in the ocean carbon system. The database covers almost half-century (1972–2019), a time-span where the mean annual atmospheric carbon dioxide concentration (CO2atm) increased from 325 to 408 ppm of volume (ppm). This increase of atmospheric CO2 (83 ppm, the 64% of the total anthropogenic signal in the atmosphere) leads to an increase in anthropogenic carbon (Cant) across all the water column and the consequent ocean acidification: a decrease in excess carbonate that is unequivocal in the upper (South Atlantic Central Water, SACW) and intermediate water masses (Sub Antarctic Mode Water, SAMW and Antarctic Intermediate Water, AAIW). For each additional ppm in CO2atm the water masses SACW, SAMW and AAIW lose excess carbonate at a rate of 0.39 ± 0.04, 0.47 ± 0.05 and 0.23 ± 0.03 μmol·kg−1·ppm−1 respectively. Modal and intermediate water masses in the Argentine Basin are very sensitive to carbon increases due low buffering capacity. The large rate of AAIW acidification is the synergic effect of carbon uptake combined with deoxygenation and increased remineralization of organic matter. If CO2 emissions follows the path of business-as-usual emissions (SSP 5.85), SACW would become undersaturated with respect to aragonite at the end of the century. The undersaturation in AAIW is virtually unavoidableFor this work M. Fontela was funded by Portuguese national funds from FCT - Foundation for Science and Technology through project UIDB/Multi/04326/2020 and CEECINST/00114/2018. A. Velo and F. F. Pérez were supported by the BOCATS2 Project (PID2019-104279GB-C21) co-funded by the Spanish Government and the Fondo Europeo de Desarrollo Regional (FEDER). A. Velo, M.Gilcoto and F. F. Pérez were supported by the European Union‘s Horizon 2020 research and innovation program under grant agreement No 820989 (project COMFORTPeer reviewe
Prevalencia de hipertensión arterial en la población de San Javier, Misiones
Full text linkFil: Ferrari, Fernando Daniel. Instituto Universitario de Ciencias de la Salud. Fundación Barceló; Argentina.Fil: Fontela, Marcos Javier. Instituto Universitario de Ciencias de la Salud. Fundación Barceló; Argentina.Fil: Lorenzo, Danny Sebastian. Instituto Universitario de Ciencias de la Salud. Fundación Barceló; Argentina.Hasta la actualidad, no existen en nuestro país estudios que utilizando criterios estrictos para el diagnóstico de hipertensión arterial (HTA) hayan determinado la prevalencia de esta patología en este grupo de población. Como parte de un proyecto de atención médica primaria realizado en el departamento de San Javier, provincia de Misiones, se efectuó un estudio de corte transversal retrospectivo con el objetivo de determinar la prevalencia de HTA, respetando los criterios que establece el consenso de HTA de 2013 de la Sociedad Argentina de Cardiología (SAC) para su diagnóstico
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Puzzling out the ecological niche construction for nitrogen fixers in a coastal upwelling system
No full textDiazotrophs are a diverse group of microorganisms that can fertilize the ocean through biological nitrogen fixation (BNF). Due to the high energetic cost of this process, diazotrophy in nitrogen-replete regions remains enigmatic. We use multidisciplinary observations to propose a novel framework for the ecological niche construction of nitrogen fixers in the upwelling region off NW Iberia-one of the most productive coastal regions in Europe-characterized by weak and intermittent wind-driven upwelling and the presence of bays. The main diazotroph detected (UCYN-A2) was more abundant and active during summer and early autumn, coinciding with relatively high temperatures (>16 degrees C), low nitrogen:phosphorus ratios (N:P 75%) to the total dissolved inorganic nitrogen available. Furthermore, nutrient amendment experiments showed that BNF is detectable when phytoplankton biomass and productivity are nitrogen limited. Seasonally recurrent biogeochemical processes driven by hydrography create an ecological niche for nitrogen fixers in this system. During the spring-summer upwelling, nondiazotroph autotrophs consume nitrate and produce organic matter inside the bays. Thereafter, the combined effect of intense remineralization on the shelf and sustained positive circulation within the bays in late summer-early autumn, conveys enhanced ammonium content and excess phosphate into the warm surface layer. The low N:P ratio confers a competitive advantage to diazotrophs since they are not restricted by nitrogen supply. The new nitrogen supply mediated by BNF could extend the productivity period, and may be a key reason why upwelling bays are more productive than upwelled offshore waters.1
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Transport and budget of carbon, nutrients and oxygen in the North Atlantic
No full text173 pages, 64 figures, 17 tablesThis thesis project is structured in five parts subdivided in eight chapters and four appendices,
whose contents, results and main findings are briefly summarized below.
Part I introduces the state of the art in the research field and sets the aim of the PhD thesis. It is
subdivided in four chapters. This introductory part starts in the Chapter 1 with a general
background of marine biogeochemical cycles, putting emphasis on the oceanic carbon cycle. The
physical oceanography of the North Atlantic it is summarized in Chapter 2, with a detailed
description of the eastern subpolar region that is the main area of study in this thesis. This chapter
also address the large scale circulation in the Atlantic, the main mode of climate variability and the
current state of knowledge about the subpolar water masses. In Chapter 3 the present concern
about the implications of anthropogenic perturbations at geological scale is presented under the
relatively new concept of Anthropocene, and chronology approaches in deep-sea sediments are
suggested. At last, in Chapter 4 the main and specific objectives of this thesis are provided.
From now on, each one of the subsequent parts of the thesis are related with specific objectives.
With the exception of the introductory chapter in Part IV (Chapter 7), each chapter is designed as
an independent entity, and structured in sections as a typical scientific publication.
In Part II the organic component of the carbon cycle is addressed. After an introduction to the
dissolved organic carbon (DOC) in the ocean carbon cycle, in the Chapter 5 is constructed a
budget of DOC for the area of study combining water masses transports with source water type
DOC characterizations. The budget is extended until subtropical latitudes (24ºN), where the
implications of the Atlantic Meridional Overturning Circulation in the total exportation of DOC
mediated by the Atlantic Ocean is evaluated for the first time.In Part III a complete biogeochemical budget for the region of study is applied. Chapter 6 update
the actual state of knowledge of carbon, nutrients and oxygen cycling in the eastern subpolar North
Atlantic. Combining long-term mass-balanced transports (2002-2016) across the OVIDE section
with public available data from a wide range of sources, a total budget of the carbon cycle in the
subpolar gyre that includes for the first time carbon variables, nutrients and oxygen was done.
Under an inverse lineal model approach, a quantification of the exportation of organic and inorganic
carbon as well as the oxygen flux in the eastern subpolar North Atlantic is given.
The geological part of the thesis dissertation is the Part IV. In the Chapter 7 the methodological
features of the innovative radiometric technique applied to date superficial deep-sea marine
sediments is fully described. To our knowledge, this is the first time that high-resolution low level
background gamma spectrometry with two simultaneous hyper-pure germanium (HPGe) detectors
is used to measure radioactivity in deep-sea samples. In Chapter 8 are showed the results of two
superficial deep-sea cores located at different basins in the subpolar North Atlantic dated with the
210Pb method. Joining geochronology information with geochemical characterization, carbon fluxes to the sediments since the Anthropocene have been estimated. As an opening approach into
carbon sedimentation in the subpolar North Atlantic, the projection of the results at basin-scale can
give a first guess of the magnitude of carbon currently exported into the sediments.The thesis dissertation ends with the main conclusions derived of this work in the Part V.
In order to ease the reading progress, all the references are grouped together as a separate
section. Finally, the four appendices at the end of the volume provide: (I) a complete list of the
acronyms, abbreviations and symbols used along with their explanations, (II) a comprehensive list
of all the figures and (III) tables indicating the pages where they appear; and (IV) a summary of the
thesis dissertation in SpanishPeer reviewe
Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Sarmiento de Gamboa Cruise in the North Atlantic Ocean on CLIVAR Repeat Hydrography Section OVIDE-2016-BOCATS (June 17 - July 31, 2016)
No full text1 file.-- This dataset compiles information obtained during the cruise BOCATS 2016This dataset gathers discrete measurements of CO2 (pH and alkalinity) and hydrographic variables (salinity, temperature, dissolved oxygen, nitrate, phosphate and silicate) obtained during the cruise BOCATS carried out along the OVIDE section from 17 June to 31 July 2016.
pH was measured spectrophotometrically following the Clayton and Byrne (1993). This method consists on adding a dye solution to the seawater sample, so that the ratio between two absorbances at two different wavelengths is proportional to the sample pH.
Alkalinity was measured using an automatic potentiometric titrator Titrando 809 Metrohm, with a Metrohm 6.0232.100 combination glass electrode and a Pt-1000 probe for temperature measurement following the methodology given by Pérez and Fraga (1987).
Dissolved oxygen was analyzed following the widely applied Winkler method.
Determinations of nitrate, phosphate and silicate were carried out following methods described by Hansen and Grassoff (1983)
Salinity and Temperature were recorded with a CTD probeBOCATS (CTM2013-41048-P)Peer reviewe
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