Synoptic patterns associated with wildfires caused by lightning in Castile and Leon, Spain

The Iberian Peninsula presents the highest number of wildfires in Europe. In the NW of Spain in particular, wildfires are the natural risk with the greatest economic impact in this region. Wildfires caused by lightning are closely related to the triggering of convective phenomena. The prediction of thunderstorms is a very complex task because these weather events have a local character and are highly dependent on mesoscale atmospheric conditions. The development of convective storms is directly linked to the existence of a synoptic environment favoring convection. The aim of this study is to classify the atmospheric patterns that provide favorable environments for the occurrence of wildfires caused by lightning in the region of Castile and Leon, Spain. The database used for the study contains 376 wildfire days from the period 1987–2006. NCEP data reanalysis has been used. The atmospheric fields used to characterise each day were: geopotential heights and temperatures at 500 hPa and 850 hPa, relative humidity and the horizontal wind at 850 hPa. A Principal Component Analysis in T-mode followed by a Cluster Analysis resulted in a classification of wildfire days into five clusters. The characteristics of these clusters were analysed and described, focusing particularly on the study of those wildfire days in which more than one wildfire was detected. In these cases the main feature observed was the intensification of the disturbance typical of the cluster to which the wildfire belongs

Electron refraction at lateral atomic interfaces

We present theoretical simulations of electron refraction at the lateral atomic interface between a “homogeneous” Cu(111) surface and the “nanostructured” one-monolayer (ML) Ag/Cu(111) dislocation lattice. Calculations are performed for electron binding energies barely below the 1 ML Ag/ Cu(111) M-point gap (binding energy EB ¼53 meV, below the Fermi level) and slightly above its C -point energy (EB ¼160 meV), both characterized by isotropic/circular constant energy surfaces. Using plane-wave-expansion and boundary-element methods, we show that electron refraction occurs at the interface, the Snell law is obeyed, and a total internal reflection occurs beyond the critical angle. Additionally, a weak negative refraction is observed for EB ¼53 meV electron energy at beam incidence higher than the critical angle. Such an interesting observation stems from the interface phase-matching and momentum conservation with the umklapp bands at the second Brillouin zone of the dislocation lattice. The present analysis is not restricted to our Cu-Ag/Cu model system but can be readily extended to technologically relevant interfaces with spinpolarized, highly featured, and anisotropic constant energy contours, such as those characteristic for Rashba systems and topological insulators. Published by AIP Publishing.Peer ReviewedPostprint (published version

Study of 11 September 2004 hailstorm event using radar identification of 2-D systems and 3-D cells

The most important hail event recorded in the region of the Ebro Valley (NE Spain) in 2004 was the 11 September episode. Large hailstones (some of them with a diameter of over 30 mm) caused important damages in agriculture and properties. The hail event affected an area of 3848 ha and was caused by several multicellular systems. The aim of this paper is the analysis of the associated convective structures using the meteorological radar as well as the MM5 mesoscale model, thermodynamic data and a hailpad network. To achieve this end, the new hailstorm analysis tool RHAP (Rainfall events and Hailstorms Analysis Program) has been applied. It identifies tracks and characterises precipitation systems and convective cells, taking into account 2-D and 3-D structures. The event has also been studied with the TITAN software (Thunderstorm Identification, Tracking, Analysis and Nowcasting) in an attempt to compare both methods. Results show that the episode had a strong convective activity with CAPE values over 4000 J/kg and with hail-forming cells characterised by VIL (Vertical Integrated Liguid) exceeding 40 kg/m², VILD (VIL density) over 4 g/m³, HP (Hail Probability) of 100% and SHP (Severe Hail Probability) of over 75%. The hail cells evolved into multicellular systems that lasted between 70 and 90 min. Finally, the comparison of RHAP and TITAN has shown significant correlations between methods

Grado de satisfacción y preferencias técnico-tácticas de jugadores de balonmano en etapas de formación según el sexo de los jugadores

The aims of this study are: a) analyse the technical and tactical preferences of handball players in both training and competition, differentiating between genders; b) learn which are the preferred actions of handball players, differentiating between genders; c) differentiate the numerical situations of play preferred by the players according to gender of the player. A selective study was carried out on players in the U-14 and U-16 categories who participated in Spain's 2012 Handball Championship for territorial teams (n = 1015), dividing them into two groups: a) male and b) female. The methodology used was the "Handball Player Satisfaction and Preferences Questionnaire". The most important results showed that: a) the technical-tactical action preferred for both groups is to launch the ball; b) the game phase preferred for both groups is attack; c) girls show a greater preference for defence than boys; d) some defensive actions cause great satisfaction in both groups, while some feel themselves conditioned by what they believe their coaches like and ask for. These data can be used to optimise the process of teaching and learning in boys' and girls' handball, understanding that their preferences are not the same.Los objetivos del presente estudio son: a) analizar las preferencias técnico-tácticas de jugadores de balonmano, tanto en entrenamiento como en competición, diferenciando entre sexos; b) Saber cuáles son las acciones preferidas de los jugadores de balonmano diferenciando entre sexos; y c) diferenciar las situaciones de igualdad o desigualdad numérica de juego preferidas por los jugadores según el sexo del jugador. Se desarrolló un estudio de carácter  selectivo sobre los jugadores de categoría infantil y cadete que participaron en el Campeonato de España de Balonmano por selecciones territoriales de 2012 (n=1015), diferenciando dos grupos: a) masculino y b) femenino. Se utilizó como instrumento el “Cuestionario de Satisfacción y Preferencias en Jugadores de Balonmano”. Los resultados más importantes mostraron que: a) La acción técnico-táctica favorita en ambos grupos es la de lanzar; b) La fase del juego favorita en ambos grupos es la de atacar; c) las chicas muestran una mayor preferencia por la defensa que los chicos; y d) Ciertas acciones defensivas ocasionan una gran satisfacción en ambos grupos, algo que se cree condicionado por lo que creen que les gusta y que piden sus entrenadores. Estos datos pueden servir para optimizar el proceso de enseñanza-aprendizaje del balonmano en chicos y chicas, entendiendo que sus preferencias no son las mismas

Buoyancy of Atlantic bluefin tuna Thunnus thynnus eggs obtained from captive broodstock spontaneous spawning events

One way to alleviate the pressure on the wild fishery of the Atlantic bluefin tuna (BFT) and aid in its conservation could be its domestication and the development of a self-sustained industry to rear the larvae and produce fingerlings in captive conditions for further grow-out. The Spanish Institute of Oceanography (IEO) is carrying out several research projects on this target for the last 12 years. No one has yet measured the vertical distribution and the in situ buoyancy of bluefin tuna eggs in any of its spawning areas in the world (Mac Kenzie and Mariani, 2012). In the present study the density of bluefin tuna eggs has been measured, comparing it with those of other fish species, particularly Atlantic bonito. We have estimated the speed by which BFT eggs rise to the surface to get a better idea of the potential loss of spawned eggs dragged by the currents out of the cage