Critical rainfall conditions for the initiation of torrential flows: results from the Rebaixader catchment (Central Pyrenees)

Torrential flows like debris flows or debris floods are fast movements formed by a mix of water and different amounts of unsorted solid material. They generally occur in steep torrents and pose high risk in mountainous areas. Rainfall is their most common triggering factor and the analysis of the critical rainfall conditions is a fundamental research task. Due to their wide use in warning systems, rainfall thresholds for the triggering of torrential flows are an important outcome of such analysis and are empirically derived using data from past events. In 2009, a monitoring system was installed in the Rebaixader catchment, Central Pyrenees (Spain). Since then, rainfall data of 25 torrential flows (“TRIG rainfalls”) were recorded, with a 5-min sampling frequency. Other 142 rainfalls that did not trigger torrential flows (“NonTRIG rainfalls”) were also collected and analyzed. The goal of this work was threefold: (i) characterize rainfall episodes in the Rebaixader catchment and compare rainfall data that triggered torrential flows and others that did not; (ii) define and test Intensity–Duration (ID) thresholds using rainfall data measured inside the catchment by with different techniques; (iii) analyze how the criterion used for defining the rainfall duration and the spatial variability of rainfall influences the value obtained for the thresholds. The statistical analysis of the rainfall characteristics showed that the parameters that discriminate better the TRIG and NonTRIG rainfalls are the rainfall intensities, the mean rainfall and the total rainfall amount. The antecedent rainfall was not significantly different between TRIG and NonTRIG rainfalls, as it can be expected when the source material is very pervious (a sandy glacial soil in the study site). Thresholds were derived from data collected at one rain gauge located inside the catchment. Two different methods were applied to calculate the duration and intensity of rainfall: (i) using total duration, Dtot, and mean intensity, Imean, of the rainfall event, and (ii) using floating durations, D, and intensities, Ifl, based on the maximum values over floating periods of different duration. The resulting thresholds are considerably different (Imean = 6.20 Dtot-0.36 and Ifl_90% = 5.49 D-0.75, respectively) showing a strong dependence on the applied methodology. On the other hand, the definition of the thresholds is affected by several types of uncertainties. Data from both rain gauges and weather radar were used to analyze the uncertainty associated with the spatial variability of the triggering rainfalls. The analysis indicates that the precipitation recorded by the nearby rain gauges can introduce major uncertainties, especially for convective summer storms. Thus, incorporating radar rainfall can significantly improve the accuracy of the measured triggering rainfall. Finally, thresholds were also derived according to three different criteria for the definition of the duration of the triggering rainfall: (i) the duration until the peak intensity, (ii) the duration until the end of the rainfall; and, (iii) the duration until the trigger of the torrential flow. An important contribution of this work is the assessment of the threshold relationships obtained using the third definition of duration. Moreover, important differences are observed in the obtained thresholds, showing that ID relationships are significantly dependent on the applied methodology.Peer ReviewedPostprint (author's final draft

Periodontal disease affecting tooth furcations. A review of the treatments available

The molars are the teeth that suffer the greatest periodontal destruction in untreated patients. When periodontal disease affects the furcation of a tooth, the chance that it will be lost increases considerably. An increase in the exposed root surface, anatomical peculiarities and irregularities of the furcation surface all favor the growth of bacteria. These problems make it harder for the patient to maintain hygiene, and impede adequate treatment. The treatment of furcations affected by periodontal disease is one of the most difficult problems for the general dentist and periodontist. The motivation of both the attending professional and of the patient are therefore of great importance. No ideal procedure for treating such lesions exists. The present paper reviews those options that are currently available. Long-term research will be needed, along with the development of new techniques, to solve the problem of furcations affected by periodontal disease, possibly including substitution of the affected tooth by an implant

Olive groves in the province of Jaen in topographical surveys of the Instituto Geográfico y Estadístico (1874-1883)

La província de Jaén és coneguda per la gran extensió que hi ocupa l’oliverar i la importància de la seva producció d’oliva a tot el món. Tanmateix, aquesta situació de monocultiu no es generalitza fins a finals del segle xx i fins al segle XIX no es fan els passos decisius per expandir-lo. Una situació que s’emmarca en l’increment de l’espai cultivat, a causa del creixement de la població, i basat en l’assentament de la societat burgesa i el triomf dels postulats fisiocràtics. En aquest treball s’avança en l’anàlisi de l’augment esmentat des del punt de vista territorial, a partir de la reconstrucció detallada de la localització d’aquest cultiu a finals de la centúria esmentada. Per tot això, s’han utilitzat els aixecaments topogràfics realitzats per l’Instituto Geográfico y Estadístico, ja que es tracta d’una font interessant per la seva precisió i fiabilitat.La provincia de Jaén es conocida por la gran extensión que ocupa el olivar y la importancia de su producción oleícola a escala mundial. Sin embargo, esta situación de monocultivo no se generaliza hasta finales del siglo XX, y es en el XIX cuando se dan los primeros pasos decisivos para su expansión. Una situación que se enmarca en el incremento del espacio cultivado, debido al crecimiento poblacional, y apoyado en el asentamiento de la sociedad burguesa y el triunfo de los postulados fisiocráticos. En este trabajo se avanza en el análisis de ese incremento desde un punto de vista territorial, a partir de la reconstrucción detallada de la localización de este cultivo a finales de dicha centuria. Para ello se han utilizadolos levantamientos topográficos realizados por el Instituto Geográfico y Estadístico, una fuente especialmente interesante por su gran precisión y fiabilidad.La province de Jaén est connue pour la grande étendue couverte d’oliveraies et pour l’importance de sa production d’huile d’olive à l’échelle mondiale. Cependant, cette situation de monoculture ne s’est généralisée qu’à la fin du XXe siècle et c’est au xixe siècle qu’on eu lieu les premières étapes décisives pour son expansion. Cette situation se produit dans le cadre de l’augmentation de la superface cultivée, en raison de la croissance de la population, et elle s’appuie sur la création de la société bourgeoise et le triomphe de les postulats physiocratiques. Ce travail progresse dans l’analyse de cette augmentation d’un point de vue territorial, à partir de la reconstitution minutieuse de l’emplacement de cette culture à la fin de ce siècle. La source utilisée consiste en des levés topographiques réalisés par l’Instituto Geográfico y Estadístico, source intéressante de par leur précision et leur fiabilité.The province of Jaen is known worldwide for its extensive olive growing areas and the importance of its olive oil production. However, the first, decisive steps for the expansion of this monoculture did not occur until the 19th century and would not become widespread until the late 20th century when the cultivated area increased due to population growth and was supported by the establishment of a bourgeois society and the triumph of the physiocratic postulates. This paper contributes to the analysis of this increase from a territorial viewpoint based on a detailed reconstruction of the location of olive crops at the end of this century. To do so, we have used the topographical surveys of the Instituto Geográfico y Estadístico; an interesting source for their precision and reliability

Experiments with assimilation of ZTD GPS data

Ponencia presentada en: HIRLAM All-Staff Meeting 2004 celebrado en Madrid, del 1 al 3 de marzo de 2004, en el Instituto Nacional de MeteoroogíaPreliminary assimilation experiments have been performed at INM to find the impact of GPS Zenith Total Delay data with the HIRLAM 3DVar system. The two alternative background constraint formulations available in HIRLAM, namely analytical and statistical, have been tested. They have been done with emphasis in the diagnostic of the performance of the assimilation cycle using this new type of observations, as in the verification of the model forecasts. These experiments have shown an impact of the assimilation of GPS data and the background constraint approach, both on precipitation and model humidity

Monitoring of rainfall and soil moisture at the Rebaixader catchment (Central Pyrenees)

The instrumental monitoring of torrential catchments is a fundamental research task and provides necessary information to improve our understanding on the mechanisms of debris flows. While most monitoring sites include meteorological sensors and analyze the critical rainfall conditions, only very few contain soil moisture measurements. In our monitoring site, the Rebaixader catchment, 11 debris flows and 24 debris floods were detected during the last nine years. Herein, the initiation mechanisms of these torrential flows were analyzed focusing on the critical rainfall conditions and the soil water dynamics. Comparing the temporal distribution of both rainfall episodes and torrential flows, the Kernel density plots showed maximum values for rainfalls at the beginning of June, while the peak for torrential flows is at July 20th. This means that highest probability of debris flows and debris floods triggering is about 1.5 months later than the one of rainstorms in the catchment. Thus, the antecedent rainfall and especially the soil moisture conditions may influence the triggering of torrential flows. In a second step, a new updated rainfall threshold was proposed including total rainfall duration and mean intensity. The analysis of soil moisture data was more complicated and no clear trends were observed in the dataset. Therefore, additional data has to be recorded in order to quantitatively analyze the role of soil moisture on the triggering of flows and for the definition of thresholds. Some preliminary results show that the soil moisture at the beginning of a rainfall event affects the maximum increase of soil moisture, while a slight trend was visible comparing the initial soil moisture with the necessary rainfall amount to trigger a torrential flow.Postprint (published version

Nowcasting solar radiation using cloud satellite and high resolution numerical model outputs

Póster presentado en: EMS Annual Meeting: European Conference for Applied Meteorology and Climatology celebrado del 4–8 de septiembre de 2017 en Dublin, IrelandAEMET (the Spanish Meteorological Agency) is currently developing a project for the Spanish transmission system operator, Red Eléctrica de España, to improve hourly Global Horizontal Irradiance (GHI) and direct Normal Irradiance (DNI) forecasts in Spanish solar power plants. Nowcasting is a technique for very short-range forecasting (normally within 6h ahead) covering only a very specific geographic region. There is a need of using nowcasting models to forecast the availability of solar radiation in order to low electricity generating costs. We present the current status of a nowcasting tool developed by AEMET that provides every 15 min the hourly solar radiation accumulated fluxes for the coming 4 hours. The meteorological data used for this model are: satellite cloud type observations and forecasts based on high resolution winds (EUMETSAT SAFNWC/MSG software package outputs), radiation from high resolution numerical weather prediction model (HARMONIE/AROME radiation outputs) or a combination of both sources of information depending on different forecast time horizons. The accuracy of the tool has been analyzed comparing the GHI and DNI forecasts with the ground solar radiation measurements from seven stations of AEMET network. The verification results in terms of RMSE are similar to those found in the bibliography, with the advantage that the satellite component of the tool does not require the use of a model to convert satellite imagery to average insolation on the groun

Evaluación de la formación del profesorado universitario novel

Durante el curso académico 2001-2002 se desarrolló en la Universidad de Barcelona el Curso de Postgrado 'Innovación en la Docencia Universitaria' dirigido al profesorado novel de la misma. Finalizado el programa se hacía imprescindible conocer su contribución a la mejora de la docencia del profesorado debutante. A través de este estudio se pretende, por tanto, identificar y valorar los cambios, transformaciones y mejoras acaecidas en la práctica docente del profesorado novel como consecuencia de su participación en el Postgrado. El presente trabajo recoge estos aspectos articulados en una evaluación diferida del impacto del Curso de Postgrado. El enfoque metodológico usado ha sido cualitativo-fenomenológico En lo que se refiere a los criterios de evaluación, dos han sido los utilizados en este estudio: la utilidad percibida por el profesorado y la transferibilidad del conocimiento elaborado en el curso

Environmental change rate and dispersion pattern modulate the dynamics of evolutionary rescue of the cyanobacterium Microcystis aeruginosa

The rate of biodiversity loss is so high that some scientists affirm that we are being witnesses of the sixth mass extinction. In this situation, it is necessary to ask the following question: can the organisms be able to resist the environmental changes that are taking place? Recent studies have shown the possibility of a population recovering from a stress situation through evolutionary rescue (ER) events. These events depend on the size of the population, its previous history and the rate of the environmental change. The aim of this work is to add more knowledge about the ER dynamics creating stress situations with selective agents (sulphur and salinity) and using the toxic cyanobacterium Microcystis aeruginosa as a model organism. The experiments are based on exposing populations to severe stress and analyze the effect of previous dispersal events and deterioration rates on the occurrence of ER events among populations. The model consists in three different rates of environmental change (constant, slow and fast; under salinity stress we only used the first two treatments) and three dispersal models (isolated, local or global). In total, 324 and 720 populations were exposed to stressful conditions caused by sulphur and salinity, respectively. The results showed that the dispersal modes and the environmental deterioration rates modulated the occurrence of ER events. It has been observed that dispersal favours ER events for both selective agents. Regarding the rate of environmental change, we observed an increase of ER events under constant changes in the populations exposed to sulphur stress. However, ER events were higher when there was previous deterioration (i.e., slow environmental change rate) under saline stress. As a conclusion, ER events in M. aeruginosa depend on selective agent, being the probability higher for salinity than for sulphur. Thus, it could be hypothesized that general conclusions in ER studies must take into account the selective agent.This work has been financially supported by the projects CGL2014- 53682-P (Ministerio de Economía y Competitividad) and CGL2017-87314-P (Ministerio de Economía, Industria y Competitividad), and the Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech