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Oteros J.,University of Cordoba, Spain | Garcia-Mozo H.,University of Cordoba, Spain | Vazquez L.,University of Cordoba, Spain | Mestre A.,Spanish Meteorological Agency AEMET | And 2 more authors.
Agriculture, Ecosystems and Environment | Year: 2013

A detailed analysis was made of the response of olive floral phenology to climate and topography in southern Spain. Field phenological, topographical and meteorological data collected at 12 sampling sites in the province of Córdoba over a 17-year period (1996-2012) were statistically analyzed and used to model local olive phenological behaviour.The study sought to determine: (1) the optimal frequency of phenological sampling during the reproductive period; (2) the major topographical parameters governing local olive reproductive phenology; and (3) the most influential meteorological variables. Findings for the Sign test indicated that weekly sampling yielded accurate results. Correlation and multiple linear regression analysis revealed that altitude and percentage eastward slope were the most influential topographical factors; a positive correlation was detected between delays in phenophases onset and increased altitude and eastward orientation. Correlation and partial least square regression analysis identified air temperature, rainfall, crop evapotranspiration and solar radiation as the major weather factors influencing local olive phenology. © 2013 Elsevier B.V. Source

Iversen T.,Norwegian Meteorological Institute | Deckmyn A.,Royal Meteorological Institute of Belgium | Santos C.,Spanish Meteorological Agency AEMET | Sattler K.,Danish Meteorological Institute | And 3 more authors.
Tellus, Series A: Dynamic Meteorology and Oceanography | Year: 2011

Grand Limited Area Model Ensemble Prediction System (GLAMEPS) is prepared for pan-European, short-range probabilistic numerical weather prediction of fine synoptic-scale, quasi-hydrostatic atmospheric flows. Four equally sized ensembles are combined: EuroTEPS, a version of the global ECMWF EPS with European target; AladEPS, a downscaling of EuroTEPS using the ALADIN model; HirEPS-K and HirEPS-S, two ensembles using the HIRLAM model nested into EuroTEPS including 3DVar data-assimilation for two control forecasts. A 52-member GLAMEPS thus samples forecast uncertainty by three analysed initial states combined with 12 singular vector-based perturbations, four different models and the stochastic physics tendencies in EuroTEPS. Over a 7-week test period in winter 2008, GLAMEPS produced better results than ECMWF's EPS with 51 ensemble members. Apart from spatial resolution, the improvement is due to the multimodel combination and to a smaller extent the dedicated EuroTEPS. Ensemble resolution and reliability are both improved. Combining uncalibrated ensembles is seen to produce a better combined ensemble than the best single-model ensemble of the same size, except when one of the single-model ensembles is considerably better than the others. Bayesian Model Averaging improves reliability, but needs further elaboration to account for geographical variations. These conclusions need to be confirmed by long-period evaluations. © 2011 The Authors Tellus A © 2011 John Wiley & Sons A/S. Source

Hazeleger W.,Royal Netherlands Meteorological Institute | Severijns C.,Royal Netherlands Meteorological Institute | Semmler T.,Met Eireann | Stefanescu S.,European Center for Medium Range Weather Forecasts | And 29 more authors.
Bulletin of the American Meteorological Society | Year: 2010

The EC-Earth consortium is a grouping of meteorologists and Earth-system scientists from 10 European countries, put together to face the challenges of climate and weather forecasting. The NWP system of the European Centre for Medium-Range Weather Forecasts (ECWMF) forms the basis of the EC-Earth Earth-system model. NWP models are designed to accurately capture short-term atmospheric fluctuations. They are used for forecasts at daily-to-seasonal time scales and include data assimilation capabilities. Climate models are designed to represent the global coupled ocean-atmosphere system. The atmospheric model of EC-Earth version 2, is based on ECMWF's Integrated Forecasting System (IFS), cycle 31R1, corresponding to the current seasonal forecast system of ECMWF. The EC-Earth consortium and ECMWF are collaborating on development of initialization procedures to improve long-term predictions. The EC-Earth model displays good performance from daily up to inter-annual time scales and for long-term mean climate. Source

Mora Garcia M.,Spanish Meteorological Agency AEMET | Riesco Martin J.,Spanish Meteorological Agency AEMET | Rivas Soriano L.,University of Salamanca | de Pablo Davila F.,University of Salamanca
Atmospheric Research | Year: 2015

The impact of land use on lightning activity has mainly been studied for urban areas; however the number of authors addressing the impact of vegetation on lightning is fairly limited. The relationship of different types of land use and soil (thirteen categories of land use and fourteen major soil types were considered) on cloud-to-ground lightning activity was studied in the Spanish region of Castilla-León from 2000 to 2010. To do this, urban, mining, and industrial areas were found to be associated with enhanced CG-lightning activity. With respect to natural land uses, forest and shrubland were the categories where CG-lightning was seen to be increased. By contrast, non-agricultural vegetated areas and pastures displayed the lowest CG-lightning activity. When the major soil types are considered, rendzinas, podzols, and phaeozems were found to be associated with a slight increase in CG-lightning activity and gleysols and solonchaks seem to decrease it. Assuming there are a plethora of factors which can indirectly affect the charging electromicrophysics and cloud dynamics, the authors provide evidence that soil type shows a significant correlation on CG-lightning flash density and weather characteristics are affected by land uses. It is suggested that the influence of vegetation and soil on surface moisture is one of the main effects contributing to explain the impact of land cover on CG-lightning. © 2015 Elsevier B.V. Source

Riesco Martin J.,Spanish Meteorological Agency AEMET | Mora Garcia M.,Spanish Meteorological Agency AEMET | de Pablo Davila F.,University of Salamanca | Rivas Soriano L.,University of Salamanca
Atmospheric Research | Year: 2013

A study of severe rainfall (≥. 100. mm in 24. h) over the Spanish provinces of Malaga, Granada y Almeria (close to the Alboran Sea, the westernmost part of the Mediterranean Sea) has been performed using 5. years (2006-2010) of data. The episodes of heavy rainfall were classified using the moisture flux at the 850. hPa pressure level and the lifted index. This gave three types, associated with situations of intense moisture flux and little static instability, moderate moisture flux and static instability, and moderate moisture flux and strong static instability. Representative cases of each type were analyzed, and it was found that both non-convective (41% of cases) and convective (59% of cases) systems caused the episodes of severe precipitation considered in this study. The convective structures included isolated and persistent convective systems, multicellular convective systems, and mesoscale convective systems. © 2013 Elsevier B.V. Source

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