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Basagana X.,Center for Research in Environmental Epidemiology | Basagana X.,Municipal Institute of Medical Research IMIM Hospital Del Mar | Basagana X.,CIBER ISCIII | Sartini C.,Center for Research in Environmental Epidemiology | And 18 more authors.
Epidemiology | Year: 2011

Background: Mortality has been shown to increase with extremely hot ambient temperatures. Details on the specific cause of mortality can be useful for improving preventive policies. Infants are often identified as a population that is vulnerable to extreme heat conditions; however, information on heat and infant mortality is scarce, with no studies reporting on cause-specific mortality. Methods: The study includes all deaths in the Catalonia region of Spain during the warm seasons of 1983-2006 (503,389 deaths). We used the case-crossover design to evaluate the association between the occurrence of extremely hot days (days with maximum temperature above the 95th percentile) and mortality. Total mortality and infant mortality were stratified into 66 and 8 causes of death, respectively. Results: Three consecutive hot days increased total daily mortality by 19%. We calculated that 1.6% of all deaths were attributable to heat. About 40% of attributable deaths did not occur during heat-wave periods. The causes of death that were increased included cardiovascular and respiratory diseases, mental and nervous system disorders, infectious and digestive system diseases, diabetes, and some external causes such as suicide. In infants, the effect of heat was observed on the same day and was detected only for conditions originating in the perinatal period (relative risk = 1.53 [95% confidence interval = 1.16-2.02]). Within the perinatal causes, cardiovascular, respiratory, digestive system, and hemorrhagic and hematologic disorders were the causes of death with stronger effects. Conclusions: Heat contributes to an increase in mortality from several causes. In infants, the first week of life is the most critical window of vulnerability. © 2011 Lippincott Williams & Wilkins.

Perez-Zanon N.,Rovira i Virgili University | Casas-Castillo M.C.,Polytechnic University of Catalonia | Rodriguez-Sola R.,Polytechnic University of Catalonia | Pena J.C.,Servei Meteorologic de Catalonia | And 3 more authors.
Theoretical and Applied Climatology | Year: 2015

The relationship between maximum rainfall rates for time intervals between 5 min and 24 h has been studied from almost a century (1905–2003) of rainfall data registered in the Ebre Observatory (Tarragona, Spain). Intensity–duration–frequency (IDF) curves and their master equation for every return period in the location have been obtained, as well as the probable maximum precipitation (PMP) for all the considered durations. In particular, the value of the 1-day PMP has resulted to be 415 mm, very similar to previous estimations of this variable for the same location. Extreme rainfall events recorded in this period have been analyzed and classified according to their temporal scale. Besides the three main classes of cases corresponding to the main meteorological scales, local, mesoscale, and synoptic, a fourth group constituted by complex events with high-intensity rates for a large range of durations has been identified also, indicating the contribution of different scale meteorological processes acting together in the origin of the rainfall. A weighted intensity index taking into account the maximum rainfall rate in representative durations of every meteorological scale has been calculated for every extreme rainfall event in order to reflect their complexity. © 2015 Springer-Verlag Wien

Casas M.C.,Polytechnic University of Catalonia | Rodriguez R.,Polytechnic University of Catalonia | Prohom M.,Servei Meteorologic de Catalonia | Gazquez A.,Servei Meteorologic de Catalonia | Redano A.,University of Barcelona
International Journal of Climatology | Year: 2011

The main objective of this study is to estimate the probable maximum precipitation (PMP) in Barcelona for durations ranging from 5 min to 30 h. To this end, rain records from the Jardí gauge of the Fabra Observatory located in Barcelona (1927-1992) and the urban pluviometric network supported by Clavegueram de Barcelona, S.A. (CLABSA, 1994-2007) were analysed. Two different techniques were used and compared: a physical method based on the maximization of actual storms, and the Hershfield' statistical method. The PMP values obtained using the two techniques are very similar. In both cases, the expected increasing behaviour of the PMP with duration was found, with the increase especially notable for the mesoscale durations 2-9 h, and not significant from 12 h on up. This result seems to be related to the scale of the meteorological situations producing high intense rainfall amounts over our territory. © 2010 Royal Meteorological Society.

Mendoza E.T.,Polytechnic University of Catalonia | Mendoza E.T.,Laboratorio Of Ingenieria Y Procesos Costeros | Jimenez J.A.,Polytechnic University of Catalonia | Mateo J.,Servei Meteorologic de Catalonia
Natural Hazards and Earth System Science | Year: 2011

A 5-class intensity scale for wave storms in the Catalan coast is presented. This has been done by analysing a storm data set which comprises 5 buoys during the period 1988/2008. The obtained classification improves the former proposal of Mendoza and Jiménez (2008) by better resolving spatial and temporal variability in wave storms in the area. The obtained classification reflects the increase in wave storm properties as the storm category increases. Because the selected classification parameter was the energy content which implicitly contains Hs and storm duration, this variable was used to define class limits; class I storms (24-250 m2 h), class II storms (251-500 m2 h), class III (501-700 m2 h), class IV storms (701-1200 m2 h) and class V storms (>1200 m2 h). The energy content variable was also used as proxy for induced hazards; the observed increase in energy content for higher classes reflected a significant increase in the intensity of the potential hazards. Lastly, the dominant synoptic situation for wave storms along the Catalan coast was the presence of a Mediterranean cyclone although a direct correspondence on cyclone's intensity over the western Mediterranean with wave energy content was not found. © Author(s) 2011.

Montanya J.,Polytechnic University of Catalonia | Van Der Velde O.,Polytechnic University of Catalonia | Sola G.,Polytechnic University of Catalonia | Fabro F.,Polytechnic University of Catalonia | And 3 more authors.
2014 International Conference on Lightning Protection, ICLP 2014 | Year: 2014

In this paper size and duration of lightning flashes are examined. Data from the Ebro Valley Laboratory Lightning Mapping Array is used as reference. Additional data from the VLF/LF LINET network and meteorological radar is included. In order to simplify the complex geometry of a lightning flash, each flash is described by a confidence ellipse fitting most of the detected sources. The flash length is represented by the major axis of the ellipse. The analysis of 1047 flashes in a set of different type of thunderstorms results in a median flash length of ∼20 km with a median duration of ∼0.4 s. The results presented here, besides characterizing the storm activity, provide valuable information in order to improve the stroke grouping criteria in the flash algorithm, lightning flash density calculations and lightning warning procedures. © 2014 IEEE.

Aran M.,Servei Meteorologic de Catalonia | Pena J.C.,Servei Meteorologic de Catalonia | Tora M.,Associacio Defensa Vegetals de Terres de Ponent
Atmospheric Research | Year: 2011

Although the advance of powerful computers has improved the outputs of meteorological models, a good synoptic classification can be very useful for weather forecasting. Therefore, the Meteorological Service of Catalonia is working on drawing up an accurate classification for extreme events. Hail events on the Lleida plain (inland Catalonia) were chosen to test different classifications. Since 1990 the Associació de Defensa Vegetal-Terres de Ponent has been collecting information on hailstorms and the damage caused in this area. Only the hail events with high impact were used to obtain the main synoptic patterns. A manual and an objective classification were carried out using the ERA-Interim reanalyses. The manual classification was done with the same variables (mean sea level pressure, temperature at 850. hPa and geopotential at 500. hPa) and the same domain as used in the objective classification. The methodology of the objective classification consisted of three steps. Firstly, a principal component analysis was used to reduce the dimension of the variables. Then, cluster analysis was applied to the component scores to obtain the atmospheric patterns. Finally, a discriminant analysis of the clusters was performed in order to improve the classification and to evaluate its goodness. Nine synoptic patterns were obtained in both classifications. © 2010 Elsevier B.V.

Calbo J.,University of Girona | Sanchez-Lorenzo A.,ETH Zurich | Barrera-Escoda A.,Servei Meteorologic de Catalonia | Cunillera J.,Servei Meteorologic de Catalonia
Tethys | Year: 2012

The publication of the fourth IPCC report, as well as the number of research results reported in recent years about the regionalization of climate projections, were the driving forces to justify the update of the report on climate change in Catalonia. Specifically, the new IPCC report contains new climate projections at global and continental scales, while several international projects (especially European projects PRUDENCE and ENSEMBLES) have produced continental-scale climate projections, which allow for distinguishing between European regions. For Spain, some of these results have been included in a document commissioned by the"State Agency of Meteorology". In addition, initiatives are being developed within Catalonia (in particular, by the Meteorological Service of Catalonia) to downscale climate projections in this area. The present paper synthesizes results of these and other previously published studies, as well as our own analysis of results of the ENSEMBLES project. The aim is to propose scenarios of variation in temperature and rainfall in Catalonia during the 21st Century. Thus, by the middle of this century temperatures could rise up to 2 C compared with that of the late 20th Century. These increases would probably be higher in summer than in winter, generalized across the territory but less pronounced in coastal areas. Rainfall, however, would not change much, but it could slightly decrease. Towards the end of the 21st Century, temperatures could rise to about 5 C above that of the last century, while the average rainfall could decrease by more than 10%. Increases in temperature would be higher in summer and in areas further from the coast. Rainfall would decrease especially during the summer, while it could even increase in winter in mountainous areas such as the Pyrenees. © 2012 Author(s).

Farguell A.,Autonomous University of Barcelona | More J.,Servei Meteorologic de Catalonia | Cortes A.,Autonomous University of Barcelona | Miro J.R.,Servei Meteorologic de Catalonia | And 2 more authors.
Procedia Computer Science | Year: 2016

Data assimilation in weather forecasting is a well-known technique used to obtain an improved estimation of the current state of the atmosphere (analysis). The Meteorological Service of Catalunya (SMC) is seeking for a real time high resolution analysis of surface parameters over Catalonia (north-east of Spain), in order to know the current weather conditions at any point of that region. For this purpose, a comparative study among several data assimilation experiments based on LAPS (Local Analysis and Prediction System) and STMAS (Space-Time Multiscale Analysis System) and multi-regression technique designed at SMC, has been performed to determine which one delivers best results. The comparison has been done using as true state independent observational data provided by the Spanish Meteorological State Agency (Agencia Estatal de METeorologia, AEMET). The results show that the multi-regression technique provides more accurate analyses of temperature and relative humidity than the LAPS/STMAS experiments, mainly due to the fact that multi-regression methodology only uses observations and consequently the model biases are avoided. © The Authors. Published by Elsevier B.V.

Barnolas M.,University of Barcelona | Rigo T.,Servei Meteorologic de Catalonia | Llasat M.C.,University of Barcelona
Hydrology and Earth System Sciences | Year: 2010

Flood simulation studies use spatial-temporal rainfall data input into distributed hydrological models. A correct description of rainfall in space and in time contributes to improvements on hydrological modelling and design. This work is focused on the analysis of 2-D convective structures (rain cells), whose contribution is especially significant in most flood events. The objective of this paper is to provide statistical descriptors and distribution functions for convective structure characteristics of precipitation systems producing floods in Catalonia (NE Spain). To achieve this purpose heavy rainfall events recorded between 1996 and 2000 have been analysed. By means of weather radar, and applying 2-D radar algorithms a distinction between convective and stratiform precipitation is made. These data are introduced and analyzed with a GIS. In a first step different groups of connected pixels with convective precipitation are identified. Only convective structures with an area greater than 32 km 2 are selected. Then, geometric characteristics (area, perimeter, orientation and dimensions of the ellipse), and rainfall statistics (maximum, mean, minimum, range, standard deviation, and sum) of these structures are obtained and stored in a database. Finally, descriptive statistics for selected characteristics are calculated and statistical distributions are fitted to the observed frequency distributions. Statistical analyses reveal that the Generalized Pareto distribution for the area and the Generalized Extreme Value distribution for the perimeter, dimensions, orientation and mean areal precipitation are the statistical distributions that best fit the observed ones of these parameters. The statistical descriptors and the probability distribution functions obtained are of direct use as an input in spatial rainfall generators.

Rigo T.,Servei Meteorologic de Catalonia | Carmen Llasat M.,University of Barcelona
Atmospheric Research | Year: 2016

The main goal of the present paper is to propose some new criteria that will improve the diagnosis for hail at the surface in real-time, so that they can be applied to surveillance tasks and for nowcasting purposes. The criteria are based on a better knowledge of convective cells that produce hail during their life cycle and better distinguishing between these cells and cells that do not produce hail on the surface. The work focused on a region in the northeast of the Iberian Peninsula, selecting hail events that occurred in the 2004-2012 period and using the information provided by the Meteorological Service of Catalonia's weather radar network. The methodology deals with the analysis of the level of reflectivity associated with the maximum values, which can be considered as the core of the convective vertical development. The chosen radar parameters are operative and they take into consideration the following: the reflectivity, the vertically integrated liquid, the highest altitude at which radar echoes have been observed over a determined reflectivity threshold, as well as the direction and the duration of the convective cells. This work aims to complement all the previous work carried out by different authors, in order to better identify hail in the chosen region. © 2015 Elsevier B.V.

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