Fernando Fraga Rodríguez (Santiago de Compostela, 1922 – Vigo, 2020)

4 pagesPeer reviewe

Seasonal patterns and long-term trends in an estuarine upwelling ecosystem (Ria de Vigo, NW Spain)

16 páginas, 10 figuras, 4 tablasThermohaline properties, nutrient salts, chlorophyll a and meteorological variables have been intensively monitored since February 1987 in the Ría de Vigo (NW Spain), in order to examine the temporal variability and the relationships between these variables over different time scales. In this paper, the seasonal and the long-term components of the 1987–92 time series are analysed. The seasonal changes in thermohaline properties are forced by meteorological factors, but whereas temperature shows a well-defined annual cycle, salinity presents a higher frequency variation pattern due to the influence of upwelling–downwelling events and runoff. Nutrient concentrations change in a regular way through the seasons, so that characteristic and well-defined cycles are observed, but they are different for each nutrient and, for a given nutrient, exhibit a marked contrast between surface and bottom layers. The seasonal changes of nutrients are not explainable by advection and water column processes alone; fractionation of nutrients during recycling and, presumably, sedimentary processes should also play an important role. The annual cycle of chlorophyll a shows a bimodal pattern, which corresponds with the development of the spring and autumn blooms; even though the seasonal cycle accounts for an important amount of the observed temporal variability, variation at lower time scales is also important. Long-term trends, as a change in the mean level of the analysed time series, have been observed for most of the variables. Salinity increased and temperature decreased both for surface and bottom series. The largest trend, in terms of the percentage to the observed variability it represents, was an increase in bottom salinity. In relation to nutrient salts, there was no evidence of increasing eutrophication, although surface dissolved inorganic nitrogen, and surface and bottom phosphate increased slightly. Chlorophyll a concentration showed a decreasing trend, especially at the surface. The observed long-term trends could be attributed to changes of the meteorological factors that operate through an increase in the estuarine residual circulation.Support for this work came from CICYT project AMB 92-0165 and EC MAST project CT90- 0017.Peer reviewe

The “Golden Chapel” of the convent of Calatrava la Nueva: Iconographic precisions and patronage

El comendador García de Padilla, miembro de un importante linaje y vinculado a la corte de Carlos V, planeó su enterramiento en el templo de la sede de la Orden Militar de Calatrava. Para ello consiguió la llamada “Capilla Dorada”, comprada al embajador don Francisco de Rojas, en la que se emprendieron diversas obras de ornamentación, destinadas no solo a reflejar un determinado programa iconográfico de tipo religioso, sino también a recordar perpetuamente los vínculos de Padilla con el emperador. El propósito principal de este trabajo es, por una parte, analizar la iconografía de dicha capilla, pero especialmente se pretende contribuir al estudio de los usos y actitudes ante la muerte entre las élites de la Edad Moderna, donde las obras de arte se convierten en portadoras de mensajes propagandísticos destinados en gran medida, a la exaltación del linajeThe knight commander (comendador) García de Padilla, a descent of an important lineage related to Carlos V court, planned his burial in the temple of the Calatrava fortress, headquarters of this Military Order. With this purpose in mind, he bought from the ambassador D. Francisco de Rojas the so-called “Golden chapel”, in which he undertook several ornamentation works. This decoration was aimed not only to represent a religious iconographic program, but a perpetual reminder of his relationship with the emperor. The aim of this paper is two-fold: first, to analyze the iconography of the above mentioned chapel and, more important, to increase our knowledge of the habits and attitudes towards death among Modern Age elites, where art conveys a propagandistic message, mainly aimed at the exaltation of their nobilit

Chemical composition of phytoplankton and Particulate Organic Matter in the Ría de Vigo (NW Spain)

15 pages, 2 figures, 7 tables.Elemental (C, H, O, N, Si, P) and biochemical composition (proteins, carbohydrates, lipids, phosphorus compounds, chlorophyll and opal) in particulate organic matter, diatoms, other autotrophs, heterotrophs and detritus from natural plankton were established simultaneously by measuring relatively few components. Using standard techniques in marine chemistry on board ship, it is possible to infer a great deal about the composition and condition of the plankton. In addition, the organic matter content in terms of cell volume was determined for each group of plankton. Variation of chemical composition with depth was also considered. The ratio carbohydrates/lipids (Cbh/Lip) was used as an indicator of the chemical quality of the plankton.This paper was supported by the Consellería de Educación of the Xunta de Galicia and Comisión Interministerial de Ciencia y Tecnología (CICYT) Grant No. MAR88-245.Peer reviewe

The Global Ocean Data Analysis Project version 2 (GLODAPv2) – an internally consistent data product for the world ocean

27 páginas, 11 tablas, 9 figuras.-- Are Olsen ... et al.-- This work is distributed under the Creative Commons Attribution 3.0 License.-- Proyecto CarbochangeVersion 2 of the Global Ocean Data Analysis Project (GLODAPv2) data product is composed of data from 724 scientific cruises covering the global ocean. It includes data assembled during the previous efforts GLODAPv1.1 (Global Ocean Data Analysis Project version 1.1) in 2004, CARINA (CARbon IN the Atlantic) in 2009/2010, and PACIFICA (PACIFic ocean Interior CArbon) in 2013, as well as data from an additional 168 cruises. Data for 12 core variables (salinity, oxygen, nitrate, silicate, phosphate, dissolved inorganic carbon, total alkalinity, pH, CFC-11, CFC-12, CFC-113, and CCl4) have been subjected to extensive quality control, including systematic evaluation of bias. The data are available in two formats: (i) as submitted but updated to WOCE exchange format and (ii) as a merged and internally consistent data product. In the latter, adjustments have been applied to remove significant biases, respecting occurrences of any known or likely time trends or variations. Adjustments applied by previous efforts were re-evaluated. Hence, GLODAPv2 is not a simple merging of previous products with some new data added but a unique, internally consistent data product. This compiled and adjusted data product is believed to be consistent to better than 0.005 in salinity, 1 % in oxygen, 2 % in nitrate, 2 % in silicate, 2 % in phosphate, 4 µmol kg−1 in dissolved inorganic carbon, 6 µmol kg−1 in total alkalinity, 0.005 in pH, and 5 % for the halogenated transient tracersThe GLODAPv2 project itself received support from a number of agencies and projects. Importantly, the EU-IP CARBOCHANGE (FP7 264878) provided funding for A. Olsen, M. Hoppema, S. van Heuven, and T. Tanhua as well as travel support for R. Key and the project framework that instigated GLODAPv2. A. Olsen further acknowledges generous support from the FRAM – High North Research Centre for Climate and the Environment, the Centre for Climate Dynamics at the Bjerknes Centre for Climate Research, the EU AtlantOS (grant agreement no. 633211) project, and the Norwegian Research Council project SNACS (229752). R. Key was supported by KeyCrafts grant 2012-001, CICS grants NA08OAR4320752 and NA14OAR4320106, NASA grant NNX12AQ22G, NSF grants OCE-0825163 (with a supplement via WHOI P.O. C119245) and PLR-1425989, and Battelle contract #4000133565 to CDIAC. A. Kozyr was supported by DOE contract DE-AC05-00OR2272 to UT-Battelle, operators of CDIAC under ORNL. S. K. Lauvset and E. Jeansson appreciate support from the Norwegian Research Council (projects DECApH, 214513 and VENTILATE, 229791). The International Ocean Carbon Coordination Project (IOCCP) also supported this activity through the U.S. National Science Foundation grant (OCE- 1243377) to the Scientific Committee on Oceanic Research. A. Velo and F. F. Pérez acknowledge the support provided by BOCATS project (CTM2013-41048-P) co-funded by the Spanish Government and the Fondo Europeo de Desarrollo Regional (FEDER), and the AtlantOS project (grant agreement no. 633211) funded by EU H2020 research and innovation programme.Peer reviewe

North Atlantic western boundary currents are intense dissolved organic carbon streams

In the North Atlantic, there are two main western boundary currents related to the Atlantic Meridional Overturning Circulation (AMOC): the Gulf Stream flowing northward and the Deep Western Boundary Current (DWBC) flowing southward. Here we analyze data from the OVIDE section (GO-SHIP A25 Portugal-Greenland 40-60 degrees N) that crosses the DWBC and the northward extension of the Gulf Stream, the North Atlantic Current. We show that North Atlantic western boundary currents play a key role in the transport of dissolved organic matter, specifically dissolved organic carbon (DOC). Revisited transports and budgets of DOC with new available data identify the eastern Subpolar North Atlantic (eSPNA) as an important source of locally produced organic matter for the North Atlantic and a key region in the supply of bioavailable DOC to the deep ocean. The East Greenland Current, and its upstream source the East Reykjanes Ridge Current on the eastern flank of the mid-Atlantic ridge, are export pathways of bioavailable DOC toward subtropical latitudes. The fast overturning and subsequent remineralization of DOC produced in the autotrophic eSPNA explains up to 38% of the total oxygen consumption in the deep North Atlantic between the OVIDE section and 24 degrees N. Carbon budgets that do not take into account this organic remineralization process overestimates the natural uptake of carbon dioxide (CO2) from the atmosphere by one third. The inclusion of DOC transports in regional carbon budgets reconciles the estimates of CO2 uptake in the North Atlantic between model and observations.FCT: UID/Multi/04326/2019/ CEECINST/00114/2018.info:eu-repo/semantics/publishedVersio

CO2 antropogénico en la región de las Azores

The AZORES-I cruise was conducted in August 1998, spanning the length of three latitudinal large-scale sections at 22, 28 and 32ºW. The oceanic carbon system was oversampled by measuring total alkalinity, total inorganic carbon and pH. It is thus possible to estimate anthropogenic CO2 (CANT) and to investigate its relationship with the main water masses that are present. C CANT is calculated using the latest back-calculation techniques: φCTº and TrOCA methods. Although the two approaches produce similar vertical distributions, the results of the TrOCA method show higher CANT variability and produce higher inventories than those of the φCTº method. The large proportion of Mediterranean Water found in the northern part of the study area is the main cause of the observed increase northwards of C CANT inventories. Changes in C CANT inventories between 1981 and 2004 are evaluated using data from the TTO-NAS, OACES-93 and METEOR-60/5 cruises. According to the φCTº and TrOCA approaches, the average long-term rates of C CANT inventory change are 1.32±0.11 mol C m-2 y-1 (P=0.008) and 1.18±0.16 mol C m-2 y-1 (P=0.018), respectively. During the 1993-1998 a significant increase in the C CANT storage rate was detected by the φCTº method. It is thought that this stems directly from the enhanced Labrador Seawater formation after the increased advection observed at the time.La campaña de macro-escala Azores I se desarrolló durante el mes de agosto de 1998 y consta de tres secciones meridionales centradas en 22, 28 y 32ºW. El sobre-muestreo realizado del sistema del carbónico, con medidas de alcalinidad total, carbono inorgánico total y pH, ha permitido el cálculo del CO2 antropogénico (CANT) e investigar su distribución en las masas de agua presentes. El CANT se calculó mediante las últimas técnicas de retro-cálculo disponibles: los métodos φCTº y TrOCA. A pesar de que ambos procedimientos producen distribuciones verticales similares, los resultados del método TrOCA indican mayores inventarios y variabilidad de CANT que los estimados por el método φCTº. La elevada proporción de agua mediterránea presente al norte de la región estudiada es la causa principal del aumento hacia el norte de los inventarios de CANT. Las tasas de cambio en los inventarios de CANT entre 1981 y 2004 se han evaluado utilizando datos de las campañas TTO-NAS, OACES-93 y METEOR-60/5. Según los métodos φCTº y TrOCA, las tasas de cambio promedio a largo plazo del inventario de CANT en esta zona son de 1.32±0.11 mol C m -2 y-1 (p-valor=0.008) y de 1.18±0.16 mol C m-2 y-2 (p-valor=0.018), respectivamente. Durante el periodo 1993-1998 el método φCTº detecta un aumento significativo de la tasa de acumulación de CANT provocado posiblemente por las elevadas tasas de formación de agua de Labrador, derivadas del aumento de la advección observada en dicho periodo

Climatologies of seawater CO2 chemistry variables: A neural network approach

1 poster presented at the 10th International Carbon Dioxide Conference, Interlaken, Switzerland, 21 August 2017 - 25 August 2017.-- Daniel Broullón ... et al.For decades, the anthropogenic modification of the carbon cycle has been widely studied. More recently, ocean acidification studies have increased significantly. Establishing robust climatologies of seawater CO2 chemistry variables and building models are a key point for a better understanding of the associated processes. The availability and quality of data is crucial for the evaluation of climate models and, consequently, to improve their predictions. Version 2 of the Global Ocean Data Analysis Project (GLODAPv2) is an internally consistent data product composed of data from 724 scientific cruises covering the entire global ocean. Among others, it contains seawater CO2 chemistry variables such as total alkalinity (AT), total dissolved inorganic carbon (TCO2) and pH. This sparse dataset has been subjected to extensive quality control and different interpolation techniques have been applied to extend the data coverage on a homogeneous grid (Lauvset et al. 2016). We propose a novel neural network approach to generate annual and monthly climatologies of AT, TCO2, pH and both calcite and aragonite saturation state from the GLODAPv2 dataset for the preindustrial and current periods. These climatologies are fitted to the World Ocean Atlas 2013 version 2 (WOA13v2) grid. WOA13v2 is a set of objectively analyzed (1° grid) climatological fields of different oceanographic variables (but not CO2 system) at standard depth levels for annual, seasonal, and monthly compositing periods for the World Ocean. A feed-forward neural network was chosen in a multi-layer architecture, which allows linear and nonlinear variability to be assimilated by the network. The proposed configuration is able to approximate most functions arbitrarily well (Hagan et al., 2014). We have tested different neural network designs and sizes to obtain the minimum error. For that, the number of neurons in the network was varied and different training techniques were used. The input variables introduced in the network, which must be related to AT and TCO2 variability, were latitude, longitude, depth, potential temperature, phosphate, nitrate, silicate, year, month and atmospheric pCO2. First, the network was trained with GLODAPv2 data and then AT and TCO2 fields were derived from WOA13v2 data. Saturation states and pH were computed from these two variables. The monthly pre-industrial climatology will be generated by eliminating anthropogenic carbon from the ocean.This research was supported by Ministerio de Educación, Cultura y Deporte (FPU grant FPU15/06026), Ministerio de Economía y Competitividad through the A. RIOS (CTM2016-76146-C3-1-R) project co-funded by the Fondo Europeo de Desarrollo Regional 2014-2020 (FEDER) and EU Horizon2020 through the AtlantOS project (grant agreement 633211).Peer reviewe

Consistency of cruise data of the CARINA database in the Atlantic sector of the Southern Ocean

13 pages, 9 figures, 1 table.-- M. Hoppema ... et al.Initially a North Atlantic project, the CARINA carbon synthesis was extended to include the Southern Ocean. Carbon and relevant hydrographic and geochemical ancillary data from cruises all across the Arctic Mediterranean Seas, Atlantic and Southern Ocean were released to the public and merged into a new database as part of the CARINA synthesis effort. Of a total of 188 cruises, 37 cruises are part of the Southern Ocean, including 11 from the Atlantic sector. The variables from all Southern Ocean cruises, including dissolved inorganic carbon (TCO2), total alkalinity, oxygen, nitrate, phosphate and silicate, were examined for cruise-to-cruise consistency in one collective effort. Seawater pH and chlorofluorocarbons (CFCs) are also part of the database, but the pH quality control (QC) is described in another Earth System Science Data publication, while the complexity of the Southern Ocean physics and biogeochemistry prevented a proper QC analysis of the CFCs. The area-specific procedures of quality control, including crossover analysis between stations and inversion analysis of all crossover data (i.e. secondary QC), are briefly described here for the Atlantic sector of the Southern Ocean. Data from an existing, quality controlled database (GLODAP) were used as a reference for our computations – however, the reference data were included into the analysis without applying the recommended GLODAP adjustments so the corrections could be independently verified. The outcome of this effort is an internally consistent, high-quality carbon data set for all cruises, including the reference cruises. The suggested corrections by the inversion analysis were allowed to vary within a fixed envelope, thus accounting for natural variability. The percentage of cruises adjusted ranged from 31% (for nitrate) to 54% (for phosphate) depending on the variable.This work has been done and funded as part of the EU project CARBOOCEAN (no. 511176; GOCE). Additional support from the International Ocean Carbon Coordination Project IOCCP (Maria Hood) and the hospitality of the Hanse Institute for Advanced Study (HWK Delmenhorst, Germany) was gratefully accepted. R. M. Key was supported by NOAA grants NA08OAR4320752 and NA08OAR4310820; X. Lin by NOAA grant NA08OAR4310820; A. Velo, F. F. Perez and A. F. R´ıos by grants: PGIDIT05OXIC40203PM Xunta de Galicia and CTM200627116E/MAR MEC; M. A´ lvarez by grant RYC-2006-001836; R. G. J. Bellerby by IPY project Bipolar Atlantic Thermohaline Circulation (BIAC, IPY Cluster #23) and Southern Ocean Biogeochemistry: Education and research (project no. 180328) from the Norwegian Research Council.Peer reviewe

The Hough Transform and the Impact of Chronic Leukemia on the Compact Bone Tissue from CT-Images Analysis

Computational analysis of X-ray Computed Tomography (CT) images allows the assessment of alteration of bone structure in adult patients with Advanced Chronic Lymphocytic Leukemia (ACLL), and may even offer a powerful tool to assess the development of the disease (prognostic potential). The crucial requirement for this kind of analysis is the application of a pattern recognition method able to accurately segment the intra-bone space in clinical CT images of the human skeleton. Our purpose is to show how this task can be accomplished by a procedure based on the use of the Hough transform technique for special families of algebraic curves. The dataset used for this study is composed of sixteen subjects including eight control subjects, one ACLL survivor, and seven ACLL victims. We apply the Hough transform approach to the set of CT images of appendicular bones for detecting the compact and trabecular bone contours by using ellipses, and we use the computed semi-axes values to infer information on bone alterations in the population affected by ACLL. The effectiveness of this method is proved against ground truth comparison. We show that features depending on the semi-axes values detect a statistically significant difference between the class of control subjects plus the ACLL survivor and the class of ACLL victims