The ability of a barotropic model to simulate sea level extremes of meteorological origin in the Mediterranean Sea, including those caused by explosive cyclones

Storm surges are responsible for great damage to coastal property and loss of life every year. Coastal management and adaptation practices are essential to reduce such damage. Numerical models provide a useful tool for informing these practices as they simulate sea level with high spatial resolution. Here we investigate the ability of a barotropic version of the HAMSOM model to simulate sea level extremes of meteorological origin in the Mediterranean Sea, including those caused by explosive cyclones. For this purpose, the output of the model is compared to hourly sea level observations from six tide gauge records (Valencia, Barcelona, Marseille, Civitavecchia, Trieste, and Antalya). It is found that the model underestimates the positive extremes significantly at all stations, in some cases by up to 65%. At Trieste, the model can also sometimes overestimate the extremes significantly. The differences between the model and the residuals are not constant for extremes of a given height, which limits the applicability of the numerical model for storm surge forecasting because calibration is difficult. The 50 and 10 year return levels are reasonably well captured by the model at all stations except Barcelona and Marseille, where they are underestimated by over 30%. The number of exceedances of the 99.9th and 99.95% percentiles over a period of 25 years is severely underestimated by the model at all stations. The skill of the model for predicting the timing and value of the storm surges seems to be higher for the events associated with explosive cyclones at all stations

Predicción de la circulación marina en los puertos españoles

This paper describes the first harbour circulation forecasting system implemented in Spain. The configuration design was based on previous analyses of the morphologic and hydrodynamic behaviour of three harbours: Barcelona, Tarragona and Bilbao. A nested system of oceanic models was implemented, with a scope ranging from the regional scale (with a mean horizontal resolution of 5 km) to the harbour scale (with a mean horizontal resolution of 40 m). A set of sensitivity tests was carried out in order to determine the optimal configurations. The results of the operational system were compared with available observations, revealing that the intermediate models are able to reproduce the averaged hydrodynamic behaviour but not the spatio-temporal variability. With the harbour models the quality of the forecasts improves, reaching a correlation and RMSE of ~0.6 and 6 cm s–1, respectively, for Bilbao harbour. In addition, numerical experiments were carried out to evaluate the sensitivity of the forecasts to error sources. The results suggest that the errors in the information prescribed in the lateral boundary conditions are the most influential in the quality of the predictions. Errors in the wind field also have a smaller but non-negligible influence. Although the system is in the initial implementation phase and should be improved upon in the future, it is now a useful tool for harbour management. The predictions will be very helpful for harbour operations, pollution risk management and fighting oil spills.En este artículo se describe el primer sistema operacional de predicción de la circulación en puertos implementado en España. El diseño del sistema se ha basado en un análisis previo de las características hidrodinámicas y morfológicas de tres puertos de estudio: Barcelona, Tarragona y Bilbao. Se ha establecido un sistema de modelos oceánicos anidados que cubre desde la escala regional (con una resolución media horizontal de 5 km) al dominio portuario (con una resolución de 40 m). Diferentes experimentos de sensibilidad se han llevado a cabo para determinar las configuraciones óptimas. Los resultados del sistema operacional se han comparado con las observaciones disponibles, mostrando que los modelos intermedios son capaces de resolver el comportamiento hidrodinámico promedio, pero no la variabilidad espacio-temporal. En cuanto a los modelos portuarios, la calidad de las predicciones mejora, alcanzando una correlación y un RMSE de ~0.6 y 6 cm s–1, respectivamente, para el puerto de Bilbao. Adicionalmente se han realizado diferentes experimentos para determinar la sensibilidad del sistema a distintas fuentes de error. Los resultados sugieren que los errores en las condiciones de contorno laterales son los más determinantes sobre la calidad de las predicciones portuarias. Los errores en el viento, aun siendo menos importantes, son también considerables. Pese a ser un sistema que está en su fase inicial de implementación y que debe ser mejorado en el futuro, en su estado actual ya representa una herramienta útil para la gestión portuaria. Las predicciones de circulación serán de gran ayuda para la gestión de operaciones portuarias, riesgo de contaminación o control de vertidos

Assessment of the Skill of Coupled Physical–Biogeochemical Models in the NW Mediterranean

Numerical modeling is a key tool to complement the current physical and biogeochemical observational datasets. It is essential for understanding the role of oceanographic processes on marine food webs and producing climate change projections of variables affecting key ecosystem functions. In this work, we evaluate the horizontalandverticalpatternsoffourstate-of-the-artcoupledphysical–biogeochemical models, three of them already published. Two of the models include data assimilation, physical and/or biological, and two do not. Simulations are compared to the most exhaustive dataset of in situ observations in the North Western Mediterranean, built ad hoc for this work, comprising gliders and conventional CTD surveys and complemented with satellite observations. The analyses are performed both in the whole domain and in four subregions (Catalan Shelf, Ebro Delta, Mallorca Channel, and Ibiza Channel), characterized by a priori divergent primary production dynamics and driving mechanisms. Overall, existing models offer a reasonable representation of physical processes including stratification, surface temperature, and surface currents, but it is shown that relatively small differences among them can lead to large differences in the response of biogeochemical variables. Our results show that all models are able to reproduce the main seasonal patterns of primary production both at the upper layer and at the deep chlorophyll maximum (DCM), as well as the differential behavior of the four subregions. However, there are significant discrepancies in the local variabilityoftheintensityofthewintermixing,phytoplanktonblooms,ortheintensityand depth of the DCM. All model runs show markedly contrasting patterns of interannual phytoplankton biomass in all four subregions. This lack of robustness should dissuade end users from using them to fill gaps in time series observations without assessing their appropriateness. Finally, we discuss the usability of these models for different applications in marine ecology, including fishery oceanography

Farmacología y toxicología en I+D+i: adquisición de competencias a través de un ejemplo de desarrollo de un fármaco

The implementation of the subject Pharmacology and Toxicology in R+D+i in the Pharmacy Degree, has led to the launch of a new methodological approach and teaching performance with the aim of developing the generic skills of the University of Barcelona (e.g., self-learning, team-working). An additional objective was students' integration of knowledge from different subjects in the degree which form the basis of the preclinical and clinical development of a drug. For this purpose, the teaching strategy used in the development of the subject was based on: 1) re-developing the content that students had been taught previously or were being taught in the same semester as a part of other subjects, and framing them in the environment of the pharmaceutical industry, 2) introducing new and previously unseen contents to do with drug development and toxicology, 3) developing a battery of activities to be undertaken by teams of students relating to the R+D+i of a particular drug. During the development of these activities, students have to acquire generic skills in addition to the subject-specific skills. The results obtained from the student survey give us grounds for satisfaction and allow us to consider that we have reached the goal of improving students' learning in Pharmacology and Toxicology applied to drug development in the pharmaceutical world today

Reconstruction of Mediterranean coastal sea level at different timescales based on tide gauge records

A coastal sea level reconstruction based on tide gauge observations is developed and applied to the western basin of the Mediterranean sea. The reconstructions are carried out in four frequency bands and are based on an optimal interpolation method in which the correlation between tide gauge data and all coastal points has been determined from the outputs of a numerical model. The reconstructions for frequencies lower than 1 month use monthly observations from the Permanent Service for Mean Sea Level (PSMSL) database and cover the period from 1884 to 2019. For the reconstruction of higher frequencies, hourly observations from the Global Extreme Sea Level Analysis (GESLA-2) dataset are used and cover from 1980 to 2015. Total sea level is retrieved with high accuracy from the merging of the different frequency bands. Results of a cross-validation test show that independent tide gauge series are highly correlated with the reconstructions. Moreover, they correlate significantly better with the reconstructions than with altimetry data in all frequency bands, and therefore the reconstruction represents a valuable contribution to the attempts of recovering coastal sea level. The obtained reconstructions allow us to characterize the coastal sea level variability, estimate coastal sea level trends along the entire coastline, and examine the correlation between western Mediterranean coastal sea level and the main North Atlantic climate indices. The limitations and applicability of the method to other regions are also discussed.</p

C/EBPa controls acquisition and maintenance of adult hematopoietic stem cell quiescence

Summary In blood, transcription factor C/EBPa is essential for myeloid differentiation and has been implicated in regulating self-renewal of fetal liver (FL) hematopoietic stem cells (HSCs). However, its function in adult HSCs has remained unknown. Here, using an inducible knockout model we found that C/EBPa deficient adult HSCs underwent a pronounced expansion with enhanced proliferation, characteristics resembling FL HSCs. Consistently, transcription profiling of C/EBPa deficient HSCs revealed a gene expression programme similar to FL HSCs. Moreover we observed that age-specific C/EBPa expression correlated with its inhibitory effect on HSC cell cycle. Mechanistically we identified N-Myc as C/EBPa downstream target, and loss of C/EBPa resulted in de-repression of N-Myc. Our data establish C/EBPa as a central determinant in the switch from fetal to adult HSCs

Mediterranean circulation perturbations over the last five centuries: Relevance to past Eastern Mediterranean Transient-type events

The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales

L'avaluació continuada i la millora en el rendiment acadèmic: el cas de de la Farmacologia i Toxicologia en R+D+i del Grau de Farmàcia

Podeu consultar la Vuitena trobada de professorat de Ciències de la Salut completa a: http://hdl.handle.net/2445/66524Des de la implantació de Espai Europeu d’Educació Superior i l’adopció per part de les universitats de l’avaluació continuada (AC) com a sistema d’acreditació del aprenentatges, existeix la preocupació tant per part dels estudiants com dels professors, que l’AC, entesa com la suma de proves i/o evidències parcials d’avaluació, ens porta a una disminució de notes en la franja alta de qualificació..