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NEMO on the shelf: assessment of the Iberia–Biscay–Ireland configuration  [PDF]
C. Maraldi,J. Chanut,B. Levier,G. Reffray
Ocean Science Discussions (OSD) , 2012, DOI: 10.5194/osd-9-499-2012
Abstract: A high resolution simulation covering the Iberia–Biscay–Ireland (IBI) region is set-up over July 2007–February 2009. The NEMO model is used with a 1/36° horizontal resolution on 50 z-levels in the vertical. It is forced by the astronomical potential and atmospheric forcing fields which consist of 3-hourly ECMWF analyses. Initial hydrographic conditions are derived from an Atlantic and Mediterranean Sea analyse at 1/12° from Mercator Ocean (PSY2V3 model). At the open boundaries, IBI is forced with PSY2V3 temperature and salinity fields. It is also forced with tidal currents and elevations and inverse barometer elevations. In this study we evaluate the realism of the simulation through comparisons with an extensive observational dataset including climatology, temperature and salinity profiles, satellite SST data, sea surface buoys, tide gauges, altimeter data and HF radar data. A specific interest is given to the procedure used for the validation. General aspects of the simulation and its quality are analysed and particular attention is given to the validation of high frequency processes including the diurnal cycle, barotropic and internal tides, and surges. Finally, we focus on specific aspects of the circulation on the European sea shelves and give a qualitative assessment by studying tidal fronts, and specially the Ushant front, and the winter extension of the Iberian Poleward Current along the Northern Spanish coast during winter 2007–2008.
Approaching Specialisation: Craft Production in Late Neolithic/Copper Age Iberia
Jonathan T. Thomas
Papers from the Institute of Archaeology , 2009, DOI: 10.5334/pia.325
Abstract: While political models of craft specialisation are integral to archaeological frameworks describing social complexity, they do not adequately describe the emergence of nascent specialists in the absence of concomitant regional, political and economic organisation. This paper reviews several examples of craft production in the Late Neolithic/Copper Age of southern Iberia. In particular, it focuses on the production of engraved slate plaques as an example of how Late Neolithic/Copper Age prestige objects may comprise an intermediate step in this process, approaching traditional models of craft specialisation in some respects, but defying them in others. It suggests that social practices such as the systematic production and consumption of rarefied or prestigious objects have a recursive relationship with the emergence of social complexity, forming the underlying basis of more institutionalised forms of specialisation and social inequality.
Extreme summer temperatures in Iberia: health impacts and associated synoptic conditions
R. García-Herrera, J. Díaz, R. M. Trigo,E. Hernández
Annales Geophysicae (ANGEO) , 2005,
Abstract: This paper examines the effect of extreme summer temperatures on daily mortality in two large cities of Iberia: Lisbon (Portugal) and Madrid (Spain). Daily mortality and meteorological variables are analysed using the same methodology based on Box-Jenkins models. Results reveal that in both cases there is a triggering effect on mortality when maximum daily temperature exceeds a given threshold (34°C in Lisbon and 36°C in Madrid). The impact of most intense heat events is very similar for both cities, with significant mortality values occurring up to 3 days after the temperature threshold has been surpassed. This impact is measured as the percentual increase of mortality associated to a 1°C increase above the threshold temperature. In this respect, Lisbon shows a higher impact, 31%, as compared with Madrid at 21%. The difference can be attributed to demographic and socio-economic factors. Furthermore, the longer life span of Iberian women is critical to explain why, in both cities, females are more susceptible than males to heat effects, with an almost double mortality impact value. The analysis of Sea Level Pressure (SLP), 500hPa geopotential height and temperature fields reveals that, despite being relatively close to each other, Lisbon and Madrid have relatively different synoptic circulation anomalies associated with their respective extreme summer temperature days. The SLP field reveals higher anomalies for Lisbon, but extending over a smaller area. Extreme values in Madrid seem to require a more western location of the Azores High, embracing a greater area over Europe, even if it is not as deep as for Lisbon. The origin of the hot and dry air masses that usually lead to extreme heat days in both cities is located in Northern Africa. However, while Madrid maxima require wind blowing directly from the south, transporting heat from Southern Spain and Northern Africa, Lisbon maxima occur under more easterly conditions, when Northern African air flows over the central Iberian plateau, which had been previously heated. Full Article (PDF, 1417 KB) Citation: García-Herrera, R., Díaz, J., Trigo, R. M., and Hernández, E.: Extreme summer temperatures in Iberia: health impacts and associated synoptic conditions, Ann. Geophys., 23, 239-251, doi:10.5194/angeo-23-239-2005, 2005. Bibtex EndNote Reference Manager XML
NEMO on the shelf: assessment of the Iberia-Biscay-Ireland configuration  [PDF]
C. Maraldi,J. Chanut,B. Levier,N. Ayoub
Ocean Science Discussions (OSD) , 2013, DOI: 10.5194/osd-10-83-2013
Abstract: The Iberia-Biscay-Ireland (IBI) system serves one of the 7 MyOcean "Monitoring and Forecasting Centres". A high resolution simulation covering the IBI region is set-up over July 2007–February 2009. The NEMO (Nucleus for European Modelling of the Ocean) model is used with a 1/36° horizontal resolution and 50 z-levels in the vertical. New developments have been incorporated in NEMO to make it suitable to open- as well as coastal-ocean modelling. In this paper, we pursue three main objectives: (1) give an overview of the model configuration used for the simulations; (2) give a broad-brush account of one particular aspect of this work, namely consistency verification; this type of validation is conducted upstream of the implementation of the system before it is used for production and routinely validated; it is meant to guide model development in identifying gross deficiencies in the modelling of several key physical processes; (3) show that such a regional modelling system has potential as a complement to patchy observations (an integrated approach) to give information on non-observed physical quantities and to provide links between observations by identifying broader-scale patterns and processes. We concentrate on the year 2008. We first provide domain-wide consistency verification results in terms of barotropic tides, transports, sea surface temperature and stratification. We then focus on two dynamical sub-regions: the Celtic shelves and the Bay of Biscay slope and deep regions. The model-data consistency is checked for variables and processes such as tidal currents, tidal fronts, internal tides, residual elevation. We also examine the representation in the model of a seasonal pattern of the Bay of Biscay circulation: the warm extension of the Iberian Poleward Current along the northern Spanish coast (Navidad event) in winter 2007–2008.
The record precipitation and flood event in Iberia in December 1876: description and synoptic analysis  [PDF]
Ricardo M. Trigo,Filipa Varino,Alexandre M. Ramos,José L. Zêzere,José M. Vaquero,Célia M. Gouveia,Ana Russo
Frontiers in Earth Science , 2014, DOI: 10.3389/feart.2014.00003
Abstract: The first week of December 1876 was marked by extreme weather conditions that affected the south-western sector of the Iberian Peninsula (IP), leading to an all-time record flow in two large international rivers. As a direct consequence, several Portuguese and Spanish towns and villages located in the banks of both rivers suffered serious flood damage on 7 December 1876. These unusual floods were amplified by the preceding particularly autumn wet months, with October 1876 presenting extremely high precipitation anomalies for all western Iberia stations. Two recently digitized stations in Portugal (Lisbon and Evora), present a peak value on 5 December 1876. Furthermore, the values of precipitation registered between 28 November and 7 December were so remarkable that, the episode of 1876 still corresponds to the maximum average daily precipitation values for temporal scales between 2 and 10 days. Using several different data sources, such as historical newspapers of that time, meteorological data recently digitized from several stations in Portugal and Spain and the recently available 20th Century Reanalysis, we provide a detailed analysis on the socio-economic impacts, precipitation values and the atmospheric circulation conditions associated with this event. The atmospheric circulation during these months was assessed at the monthly, daily and sub-daily scales. All months considered present an intense negative NAO index value, with November 1876 corresponding to the lowest NAO value on record since 1865. We have also computed a multivariable analysis of surface and upper air fields in order to provide some enlightening into the evolution of the synoptic conditions in the week prior to the floods. These events resulted from the continuous pouring of precipitation registered between 28 November and 7 December, due to the consecutive passage of Atlantic low-pressure systems fuelled by the presence of an atmospheric-river tropical moisture flow over central Atlantic Ocean.
An overview of a heavy rain event in southeastern Iberia: the role of large-scale meteorological conditions
F. Valero,M. Y. Luna,M. L. Martín
Annales Geophysicae (ANGEO) , 2003,
Abstract: The heavy rain event of 30 January to 4 February 1993 in the Segura Basin in SE Iberia is investigated. The study emphasizes the atmospheric processes that led to thunderstorm development. The meteorological scenario has been separated into preconvective and convective periods and into large-scale and subsynoptic settings. The warm, moist air flow from the Mediterranean Sea, channelled by a high-over-low blocking pattern with a cold front over southeastern Iberia appears to be the main reason that helped trigger a severe weather occurrence. The study of the mesoscale environment parameters showed an enhanced conditional unstability through a deep troposphere layer with a moderate to strong vertical wind shear that promoted conditions to allow organization of long-lived convective structures.
Fuel load and flight ranges of blackcaps Sylvia atricapilla in northern Iberia during autumn and spring migrations  [cached]
JUAN ARIZAGA, EMILIO BARBA
Current Zoology , 2009,
Abstract: Fuel accumulation, mainly as fatty acids, is one of the main characteristics of migratory birds. Studying to what extent each population or species manages fuel load and how it varies along routes of migration or between seasons (autumn and spring migrations) is crucial to our understanding of bird migration strategies. Our aim here was to analyse whether migratory blackcaps Sylvia atricapilla passing through northern Iberia differ in their mean fuel loads, rate of fuel accumulation and 'potential' flight ranges between migration seasons. Blackcaps were mist netted for 4 h-periods beginning at dawn from 16 September to 15 November 2003–2005, and from 1 March to 30 April 2004–2006 in a European Atlantic hedgerow at Loza, northern Iberia. Both fuel load and fuel deposition rate (this latter assessed with difference in body mass of within-season recaptured individuals) were higher in autumn than in spring. Possible hypotheses explaining these results could be seasonal-associated variations in food availability (likely lower during spring than during autumn), the fact that a fraction of the migrants captured in spring could breed close to the study area and different selective pressures for breeding and wintering [Current Zoology 55 (6): 401–410, 2009].
Springtime connections between the large-scale sea-level pressure field and gust wind speed over Iberia and the Balearics  [PDF]
M. L. Martín,F. Valero,A. Pascual,A. Morata
Natural Hazards and Earth System Sciences (NHESS) & Discussions (NHESSD) , 2011, DOI: 10.5194/nhess-11-191-2011
Abstract: This paper investigates, by means of Singular Value Decomposition analysis, the springtime relationships between the mean sea-level pressure field over the North Atlantic and the regional wind gusts over the Iberian Peninsula, identifying the main atmospheric circulation patterns linked to gust wind speed anomaly configurations. The statistical significance of the obtained modes is investigated by means of Monte Carlo approach. The analysis highlighted that the covariability is dominated by two main large-scale features of the atmospheric circulation over the North Atlantic. The first mode relates to Iberian gust wind speeds to the Scandinavian pattern (SCAND), linking the large-scale pattern to above-normal wind gusts. The second covariability mode, associated with the North Atlantic Oscillation (NAO) pattern, correlates with maximum wind speeds over Iberia. An enhanced spring NAO pattern is related to positive (negative) wind gust correlations over northern (southern) Iberia. To find true relationships between large-scale atmospheric field and the gust wind speeds, composite maps were built up to give an average atmospheric circulation associated with coherent wind gust variability over Iberia.
Crustal and upper mantle velocity structure of Southern Iberia, the sea of Alboran, and the Gibraltar arc determined by local earthquake tomography
E. Gurria,J. Mezcua,M. J. Blanco
Annals of Geophysics , 1997, DOI: 10.4401/ag-3940
Abstract: A "local earthquake tomography" of a large area encompassing the South of Iberia, the sea of Alboran, the Gibraltar arc, and Northern Morrocco, has been performed using first arrival times recorded at various Spanish and Morroccan seismic networks. A total of 52 stations and 639 earthquakes provided over 6300 first P arrivals and 4400 S arrivals. Three features of interest appear in the results: i) a continuous low velocity structure which correlates with the Betics, the Gibraltar arc and the Rif; ii) a high velocity feature which persists to a depth of approximately 30 km, positioned near the coast of Malaga on the northern margin of the Alboran sea; iii) a low velocity feature, extending to a minimum depth of approximately 40 km, which coincides with the Granada basin and a strong negative Bouguer gravity anomaly.
The Filador Rock Shelter (Margalef de Montsant, Tarragona) and its cultural and chronological context in Northeastern Iberia
García-Argüelles Andreu, Pilar,Nadal I Lorenzo, Jordi,Fullola I Pericot, Josep Ma
Trabajos de Prehistoria , 2005,
Abstract: In this paper we review briefly our twenty-years of excavation in the Filador rock shelter. We give the most important results in sedimentology, faunal remains, pollen, lithic industries and radiocarbon dates that we have obtained since 1979. We give also our opinion about the chronocultural situation of the site in the epipalaeolithic period in the northeastern Iberia, based on the radiocabon dates known until now. This is the first synthetic publication of this major site since professor Fortea reviewed the ancient excavations in 1973. The Filador rock shelter keeps on being one of the bases of the chronocultural structure of Epipalaeolithic in norteastern Iberia. En este articulo se pasa revista, de forma resumida, a 20 a os de excavaciones en el abrigo del Filador y se dan a conocer los resultados más importantes (sedimentología, fauna, polen, industria, dataciones, etc..), obtenidos con la aplicación de nuevas técnicas de estudio desde 1979. Del mismo modo replanteamos su ubicación cronocultural dentro del marco geográfico del NE peninsular a partir de las dataciones radiocarbónicas conocidas hasta el momento. Se trata del primer trabajo de síntesis sobre el yacimiento realizado con posterioridad al estudio de J. Fortea (Fortea 1973); el Filador sigue siendo un referente obligado del Epipaleolítico de la zona en tanto que muestra la mayoría de las facies cronoculturales que definen esta fase en el NE ibérico.
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