Descripció dels rastres i les petjades d'Hypnomis Bate, 1918 (Mammalia : Gliridae) de la cova de sa Duna

[eng] In this paper we describe the Hypnomys paw prints and tracks located on the surface of a pleistocene dune that partially collapsed cova de sa Duna (Alaior, Menorca). This deposit can be considerated exceptional for the number and quality of paw prints. For the firts time, Hypnomys tracks are described and hands and feet paw prints are correctly distinguished. The feet shows the “typical” morphology of Hypnomys paw prints, with elongated digital and big intermediate pads. The unique studied hand paw print shows a big rounded central pad and two little and rounded lateral pads. The tracks morphology, shaped by alternate series of paw prints couples indicated that tracks were made by jumping animals on the inclined (30º) surface of the dune. This kind of track provided a relatively scarce information about corporal proportions of Hypnomys, like body length or width-length body relationship. The absence of tail tracks possibly indicates that Hypnomys not drag the tail when it moves.[cat] En aquest treball es descriuen les petjades i els rastres d’Hypnomys localitzats a la superfície d’una duna del plistocè superior que omple parcialment la cova de sa Duna (Alaior, Menorca). Per la quantitat i la qualitat de les petjades, el jaciment de la cova de sa Duna es pot considerar com excepcional. Mentre que les petjades d’aquest mamífer ja eren conegudes en un altre jaciment menorquí (les penyes d’Alparico, Ciutadella de Menorca), és el primer cop que es troben i descriuen tres rastres d’Hypnomys. Per primera vegada també s’han pogut distingir de forma clara les empremtes dels peus i de les mans. Les petjades mostren la morfologia “típica” d’Hypnomys: presència de coixinets digitals i un gran coixinet intermedi en els peus. L’única petjada d’una mà recuperada sembla que presenta tres coixinets: un de gros central i dos de més petits situats a l’esquerra i a la dreta del coixinet central. La morfologia dels rastres (formats per sèries alternades de parells de petjades) indica que no correspon al rastre típic de pas, format per la successió de tres parells de petjades, sinó que més aviat es van formar quan els animals van passar botant damunt la superfície de la duna, possiblement a causa de la seva inclinació (30º). Per les característiques dels rastres, la informació que aquests proporcionen és relativament escassa, de forma que resulta difícil poder obtenir informació sobre la longitud real del tronc o la proporció entre la longitud i l’amplada d’aquest. D’altra banda, l’absència de marques de coa ha estat interpretada com un indici que Hypnomys no arrossegava la coa en desplaçar-se

An A-form of poly[d(A-C)] · poly[d(G-T)] induced by mercury (II) as studied by UV and FTIR spectroscopies

AbstractThe conformational changes of poly[d(A-C)]·poly[d(GT)] induced by Hg(CiO4)2 in aqueous solution have been studied using UV absorption and fourth derivative spectrophotometries, and FTIR spectroscopy. The UV absorption and fourth derivative spectra reflect changes in the polynucleotide stacking interactions as a result of the metal-polynucleotide interaction. The fourth derivative spectra do not indicate a Z-form either at low or at high metal-to-polynucleotide ratios. Furthermore, the infrared spectrum at high metal-to-polynucleotide ratio (r = 1.2; r = [Hg(ClO4)2][nucleotide] molar ratio) has the main features of an A-form, in contrast with previous CD studies which proposed that the polynucleotide adopts a Z-form under these conditions. The nature of a different conformation of the polynucleotide induced at low r-ratios (r < 0.2) is discussed

Simulation hydrologique en région méditerranéenne avec SAFRAN-ISBA-MODCOU : amélioration de la physique et évaluation des risques dans le cadre du changement climatique

Le modèle SAFRAN-ISBA-MODCOU est évalué et sa physique améliorée. L'analyse météorologique SAFRAN est tout d'abord validée en détail. Le modèle de surface ISBA est ensuite modifié pour mieux décrire la conductivité hydraulique dans le sol. Une stratégie de calibration est définie et appliquée à l'échelle de la France. Le modèle amélioré est finalement utilisé pour évaluer les impacts du changement climatique en région méditerranéenne. Un scénario d'un modèle de climat régional est désagrégé en utilisant deux méthodes différentes. L'étude montre que les incertitudes liées à la désagrégation sont importantes. L'incertitude au modèle d'impact est moindre, mais doit être prise en compte pour les extrêmes. Dans cette région les débits extrêmes et, parfois, moyens, augmenteront pendant la première moitié du XXIe siècle. A la fin du siècle le scénario indique une baisse des débits moyens décroisent et une stabilité des débits extrêmes, ce qui conduit à une augmentation de la variabilité.The SAFRAN-ISBA-MODCOU model is assessed and its physics are improved. The SAFRAN meteorological analysis is first validated in detail. The surface model ISBA is then modified to better describe the hydraulic conductivity in the soil. A strategy of calibration is defined and applied at the scale of France. The improved model is then used to assess the impacts of climate change in the Mediterranean region. A regional climate model is downscaled by two different methods. The study shows that the uncertainties related to the downscaling are important. Uncertainty related to the impact model is smaller, but must be taken into account for the extremes. In this region, the extremes of riverflows, and sometimes the means, will increase during the first half of the twenty-first century. At the end of the century, the scenario indicates a decline of the average of riverflows and the extremes will remain stable, leading to increased variability

Els vertebrats terrestres fòssils del Migjorn

Abstract not availabl

Cronologia de la desaparició de Myotragus balearicus Bate 1909 a Menorca

&#091;cat&#093; Es presenten dues noves datacions radiocarbòniques obtingudes directament sobre ossos de Myotragus balearicus provinents de jaciments de Menorca. El resultat d'una d'elles, Beta-177237 &#091;5060±40 BP; 3970-3760 (95.4%) cal BC 2s&#093;, permet establir que la desaparició de l'espècie a Menorca es va produir després del 3970 cal BC, i reforça la interpretació que aquesta desaparició es relaciona amb l'arribada dels primers humans a l'illa.&#091;eng&#093; Two new radiocarbon datings based on Myotragus balearicus bones from Menorca are presented here. The result of one of them, Beta-177237 &#091;5060±40 BP; 3970-3760 (95.4%) cal BC 2s&#093;, permit us to establish that the disappearance of this species took place on Menorca later than 3970 cal BC, and strengthens the relation between this event and the human arrival on the island

Comparison of three downscaling methods in simulating the impact of climate change on the hydrology of Mediterranean basins

International audienceStudies of the impact of climate change on water resources usually follow a top to bottom approach: a scenario of emissions is used to run a GCM simulation, which is downscaled (RCM and/or stastistical methods) and bias-corrected. Then, this data is used to force a hydrological model. Seldom, impact studies take into account all relevant uncertainties. In fact, many published studies only use one climate model and one downscaling technique. In this study, the outputs of an atmosphere-ocean regional climate model are downscaled and bias-corrected using three different techniques: a statistical method based on weather regimes, a quantile-mapping method and the method of the anomaly. The resulting data are used to force a distributed hydrological model to simulate the French Mediterranean basins. These are characterized by water scarcity and an increasing human pressure, which cause a demand in assessments on the impact of climate change hydrological systems. The purpose of the study is mainly methodological: the evaluation of the uncertainty related to the downscaling and bias-correction step. The periods chosen to compare the changes are the end of the 20th century (1970-2000) and the middle of the 21st century (2035-2065). The study shows that the three methods produce similar anomalies of the mean annual precipitation, but there are important differences, mainly in terms of spatial patterns. The study also shows that there are important differences in the anomalies of temperature. These uncertainties are amplified by the hydrological model. In some basins, the simulations do not agree in the sign of the anomalies and, in many others, the differences in amplitude of the anomaly are very important. Therefore, the uncertainty related to the downscaling and bias-correction of the climate simulation must be taken into account in order to better estimate the impact of climate change, with its uncertainty, on a specific basin. The study also shows that according to the RCM simulation used and to the periods studied, there might be significant increases of winter precipitation on the Cévennes region of the Massif Central, which is already affected by flash floods, and significant decreases of summer precipitation in most of the region. This will cause a decrease in the average discharge in the middle of the 21st in most of the gauging stations studied, specially in summer. Winter and, maybe spring, in some areas, are the exception, as discharge may increase in some basins

Validation of a new SAFRAN-based gridded precipitation product for Spain and comparisons to Spain02 and ERA-Interim

Offline Land-Surface Model (LSM) simulations are useful for studying the continental hydrological cycle. Because of the nonlinearities in the models, the results are very sensitive to the quality of the meteorological forcing; thus, high-quality gridded datasets of screen-level meteorological variables are needed. Precipitation datasets are particularly difficult to produce due to the inherent spatial and temporal heterogeneity of that variable. They do, however, have a large impact on the simulations, and it is thus necessary to carefully evaluate their quality in great detail. This paper reports the quality of two high-resolution precipitation datasets for Spain at the daily time scale: the new SAFRAN-based dataset and Spain02. SAFRAN is a meteorological analysis system that was designed to force LSMs and has recently been extended to the entirety of Spain for a long period of time (1979/80-2013/14). Spain02 is a daily precipitation dataset for Spain and was created mainly to validate Regional Climate Models. In addition, ERA-Interim is included in the comparison to show the differences between local high-resolution and global low-resolution products. The study compares the different precipitation analyses with rain gauge data and assesses their temporal and spatial similarities to the observations. The validation of SAFRAN with independent data shows that this is a robust product. SAFRAN and Spain02 have very similar scores, although the later slightly surpasses the former. The scores are robust with altitude and throughout the year, save perhaps in summer, when a diminished skill is observed. As expected, SAFRAN and Spain02 perform better than ERA-Interim, which has difficulty capturing the effects of the relief on precipitation due to its low resolution. However, ERA-Interim reproduces spells remarkably well, in contrast to the low skill shown by the high-resolution products. The high-resolution gridded products overestimate the number of precipitation days, which is a problem that affects SAFRAN more than Spain02 and is likely caused by the interpolation method. Both SAFRAN and Spain02 underestimate high precipitation events, but SAFRAN does so more than Spain02. The overestimation of low precipitation events and the underestimation of intense episodes will probably have hydrological consequences once the data are used to force a land surface or hydrological model.We are grateful to the French National Centre for Meteorological Research (CNRM UMR3539, Météo-France CNRS) for allowing us to use the code of the SAFRAN analysis system for our studies, the Spanish State Meteorological Agency (AEMET) for sharing their very valuable observational data with us and the European Centre for Medium-Range Weather Forecasts (ECMWF) for making their ERA-Interim product openly available. This is a contribution to the FP7 eartH2Observe project (http://www.earth2observer.eu), which received funding from the European Union’s Seventh Programme for research, technological development and demonstration under grant agreement no. 603608. This work has been funded by the Spanish Economy and Competitiveness Ministry and the European Regional Development Fund through grant CGL2013-47261-R. This work has been supported by the Metropolitan Area of Barcelona Project (no. 308321; flood evolution in the metropolitan area of Barcelona from a holistic perspective: past, present and future) and the Spanish Project HOPE (CGL2014-52571-R) supported by the Ministry of Economy and Competitiveness. This work is a contribution to the HyMeX program (Hydrological cycle in the Mediterranean EXperiment; http://www.hymex.org)

The Utility of Land-Surface Model Simulations to Provide Drought Information in a Water Management Context Using Global and Local Forcing Datasets

Drought diagnosis and forecasting are fundamental issues regarding hydrological management in Spain, where recurrent water scarcity periods are normal. Land-surface models (LSMs) could provide relevant information for water managers on how drought conditions evolve. Here, we explore the usefulness of LSMs driven by atmospheric analyses with different resolutions and accuracies in simulating drought and its propagation to precipitation, soil moisture and streamflow through the system. We perform simulations for the 1980-2014 period with SASER (5 km resolution) and LEAFHYDRO (2.5 km resolution), which are forced by the Spanish SAFRAN dataset (at 5km and 30km resolutions), and the global eartH2Observe datasets at 0.25 degrees (including the MSWEP precipitation dataset). We produce standardized indices for precipitation (SPI), soil moisture (SSMI) and streamflow (SSI). The results show that the model structure uncertainty remains an important issue in current generation large-scale hydrological simulations based on LSMs. This is true for both the SSMI and SSI. The differences between the simulated SSMI and SSI are large, and the propagation scales for drought regarding both soil moisture and streamflow are overly dependent on the model structure. Forcing datasets have an impact on the uncertainty of the results but, in general, this impact is not as large as the uncertainty due to model formulation. Concerning the global products, the precipitation product that includes satellite observations (MSWEP) represents a large improvement compared with the product that does notThis is a contribution to the EU-FP7 eartH2Observe project, which received funding from the European Union’s Seventh Programme for research, technological development and demonstration under grant agreement no. 603608. This work has been partially funded by the Spanish Ministry of Science, Innovation and Universities and the European Regional Development Fund through grants CGL2013-47261-R and CGL2017-85687-R. This work is a contribution to the HyMeX program (Hydrological Cycle in the Mediterranean Experiment; http://www.hymex.org)S

Use of bias correction techniques to improve seasonal forecasts for reservoirs - A case-study in northwestern Mediterranean

In this paper, we have compared different bias correction methodologies to assess whether they could be advantageous for improving the performance of a seasonal prediction model for volume anomalies in the Boadella reservoir (northwestern Mediterranean). The bias correction adjustments have been applied on precipitation and temperature from the European Centre for Middle-range Weather Forecasting System 4 (S4). We have used three bias correction strategies: two linear (mean bias correction, BC, and linear regression, LR) and one non-linear (Model Output Statistics analogs, MOS-analog). The results have been compared with climatology and persistence. The volume-anomaly model is a previously computed Multiple Linear Regression that ingests precipitation, temperature and in-flow anomaly data to simulate monthly volume anomalies. The potential utility for end-users has been assessed using economic value curve areas. We have studied the S4 hindcast period 1981-2010 for each month of the year and up to seven months ahead considering an ensemble of 15 members. We have shown that the MOS-analog and LR bias corrections can improve the original S4. The application to volume anomalies points towards the possibility to introduce bias correction methods as a tool to improve water resource seasonal forecasts in an end-user context of climate services. Particularly, the MOS-analog approach gives generally better results than the other approaches in late autumn and early winter

Exploiting High-Resolution Remote Sensing Soil Moisture to Estimate Irrigation Water Amounts over a Mediterranean Region

Despite irrigation being one of the main sources of anthropogenic water consumption, detailed information about water amounts destined for this purpose are often lacking worldwide. In this study, a methodology which can be used to estimate irrigation amounts over a pilot area in Spain by exploiting remotely sensed soil moisture is proposed. Two high-resolution DISPATCH (DISaggregation based on Physical And Theoretical scale CHange) downscaled soil moisture products have been used: SMAP (Soil Moisture Active Passive) and SMOS (Soil Moisture and Ocean Salinity) at 1 km. The irrigation estimates have been obtained through the SM2RAIN algorithm, in which the evapotranspiration term has been improved to adequately reproduce the crop evapotranspiration over irrigated areas according to the FAO (Food and Agriculture Organization) model. The experiment exploiting the SMAP data at 1 km represents the main work analyzed in this study and covered the period from January 2016 to September 2017. The experiment with the SMOS data at 1 km, for which a longer time series is available, allowed the irrigation estimates to be extended back to 2011. For both of the experiments carried out, the proposed method performed well in reproducing the magnitudes of the irrigation amounts that actually occurred in four of the five pilot irrigation districts. The SMAP experiment, for which a more detailed analysis was performed, also provided satisfactory results in representing the spatial distribution and the timing of the irrigation events. In addition, the investigation into which term of the SM2RAIN algorithm plays the leading role in determining the amount of water entering into the soil highlights the importance of correct representation of the evapotranspiration process