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Abstract. The synoptic evolution and some meteorological impacts of the European winter storm Kyrill that swept across Western, Central, and Eastern Europe between 17 and 19 January 2007 are investigated. The intensity and large storm damage associated with Kyrill is explained based on synoptic and mesoscale environmental storm features, as well as on comparisons to previous storms. Kyrill appeared on weather maps over the US state of Arkansas about four days before it hit Europe. It underwent an explosive intensification over the Western North Atlantic Ocean while crossing a very intense zonal polar jet stream. A superposition of several favourable meteorological conditions west of the British Isles caused a further deepening of the storm when it started to affect Western Europe. Evidence is provided that a favourable alignment of three polar jet streaks and a dry air intrusion over the occlusion and cold fronts were causal factors in maintaining Kyrill's low pressure very far into Eastern Europe. Kyrill, like many other strong European winter storms, was embedded in a pre-existing, anomalously wide, north-south mean sea-level pressure (MSLP) gradient field. In addition to the range of gusts that might be expected from the synoptic-scale pressure field, mesoscale features associated with convective overturning at the cold front are suggested as the likely causes for the extremely damaging peak gusts observed at many lowland stations during the passage of Kyrill's cold front. Compared to other storms, Kyrill was by far not the most intense system in terms of core pressure and circulation anomaly. However, the system moved into a pre-existing strong MSLP gradient located over Central Europe which extended into Eastern Europe. This fact is considered determinant for the anomalously large area affected by Kyrill. Additionally, considerations of windiness in climate change simulations using two state-of-the-art regional climate models driven by ECHAM5 indicate that not only Central, but also Eastern Central Europe may be affected by higher surface wind speeds at the end of the 21st century. These changes are partially associated with the increased pressure gradient over Europe which is identified in the ECHAM5 simulations. Thus, with respect to the area affected, as well as to the synoptic and mesoscale storm features, it is proposed that Kyrill may serve as an interesting study case to assess future storm impacts.

Abstract. A simple storm loss model is applied to an ensemble of ECHAM5/MPI-OM1 GCM simulations in order to estimate changes of insured loss potentials over Europe in the 21st century. Losses are computed based on the daily maximum wind speed for each grid point. The calibration of the loss model is performed using wind data from the ERA40-Reanalysis and German loss data. The obtained annual losses for the present climate conditions (20C, three realisations) reproduce the statistical features of the historical insurance loss data for Germany. The climate change experiments correspond to the SRES-Scenarios A1B and A2, and for each of them three realisations are considered. On average, insured loss potentials increase for all analysed European regions at the end of the 21st century. Changes are largest for Germany and France, and lowest for Portugal/Spain. Additionally, the spread between the single realisations is large, ranging e.g. for Germany from −4% to +43% in terms of mean annual loss. Moreover, almost all simulations show an increasing interannual variability of storm damage. This assessment is even more pronounced if no adaptation of building structure to climate change is considered. The increased loss potentials are linked with enhanced values for the high percentiles of surface wind maxima over Western and Central Europe, which in turn are associated with an enhanced number and increased intensity of extreme cyclones over the British Isles and the North Sea.

Abstract. During the last decades, several windstorm series hit Europe leading to large aggregated losses. Such storm series are examples of serial clustering of extreme cyclones, presenting a considerable risk for the insurance industry. Clustering of events and return periods of storm series for Germany are quantified based on potential losses using empirical models. Two reanalysis data sets and observations from German weather stations are considered for 30 winters. Histograms of events exceeding selected return levels (1-, 2- and 5-year) are derived. Return periods of historical storm series are estimated based on the Poisson and the negative binomial distributions. Over 4000 years of general circulation model (GCM) simulations forced with current climate conditions are analysed to provide a better assessment of historical return periods. Estimations differ between distributions, for example 40 to 65 years for the 1990 series. For such less frequent series, estimates obtained with the Poisson distribution clearly deviate from empirical data. The negative binomial distribution provides better estimates, even though a sensitivity to return level and data set is identified. The consideration of GCM data permits a strong reduction of uncertainties. The present results support the importance of considering explicitly clustering of losses for an adequate risk assessment for economical applications.

The climate changes issue is probable the top priority concern of the governments of the most countries of the world. Rigid and drastic measures have to be taken by all nations in order to reduce the noxious gases emission to the atmosphere. This ambitious goal can be achieved by ruling the energy production, by having a much more sustainable industry and adopting a much more sustainable way of living by all of us. The building industry has also to adapt to these circumstances to make its contribution to achieve the above goal. Focusing on traditional building techniques which require simple technology and use natural and local building materials and, eventually, to adapt them for the present required quality standards may be a step to solve this problem. Half of the world' population, 3 billion people approximately, on six continents, live or work in buildings constructed by earth based building materials. The fact that earth is natural, abundant and local result in an unexpressive amount of energy spending and noxious gases emission when it is used as a building material and, consequently, makes it undoubtedly much more ecological and economic when compared to the others building materials such as reinforced concrete or steel. In this context, the main objective of this research work is to give a contribution on the earth based building material properties and, in particular, for the development of adequate rehabilitation and strengthening techniques, based upon a biomimetic study focused on the andorinha-dos-beirais nest. A structural numerical model of a nest using a finite element computer analysis program was done in order to understand the structural behavior of this kind of natural structures. In order to identify a possible occurrence of a certain agglutination phenomenon during the building process of the nest by the birds, an experimental identification/characterization study of nest's material using samples taken in Vila Real area was carried out. The identification of the elementary chemical and the ...

Solar photovoltaic represent one of the most promising technologies for generating electrical energy from renewable sources. In fact, as a result of the technological advances in the field of microelectronics and power electronics, photovoltaic systems have reached historic lows in terms of costs, surpassing the other types of renewable energy sources. The potential of the solar photovoltaic systems is enormous, being capable of meeting the energy needs of today, without compromising future needs, and allowing a sustainable development. With this in mind, several incentives and, consequently, legislations have been implemented around the world. In the Portuguese case, depending on the type of contract, for photovoltaic solar installations with value of power up to 1500 Wp the production surplus is injected into the power grid without any financial compensation. Considering the high investment, particularly regarding the photovoltaic panels, the support structure and the power electronics converters, it could be interesting to implement a system capable of storing the surplus energy for later use by the owner of the photovoltaic installation. This paper presents a study on the viability of energy storage systems in photovoltaic installations up to 1500 Wp. For this study, different consumer profiles, types of installations and geographic locations were considered, in order to perceive the technological and economic viability of this solution. ; This work has been supported by FCT -Fundancao para a Ciencia e Tecnologia within the Project Scope: UID/CEC/00319/2019. This work is financed by the ERDF COMPETE 2020 Programme, and FCT within project SAICTPAC/0004/2015-POCI-01-0145-FEDER-016434 and FCT within project PTDC/EEI-EEE/28813/2017. Mr. Luis A. M. Barros is supported by the doctoral scholarship PD/BD/143006/2018 granted by the Portuguese FCT ...

Vaccination represents a key pillar of most classical swine fever (CSF) control programmes. In backyard production systems the systematic implementation of parenteral vaccination proves to be difficult and alternative delivery mechanisms might be needed. In this study the use of oral vaccination against CSF in backyard pigs was tested under field conditions. The main objective was to assess uptake efficacy and immune response after oral vaccination of backyard pigs with bait vaccine currently used in the European Union for CSF control in wild boar (RIEMSER® Schweinepestoralvakzine). In total 85 backyard pigs belonging to 16 holdings were vaccinated orally by distributing four baits per pig, given on two consecutive days. The baits were distributed on pen floors. 73% of the pigs older than 12 weeks (n = 41) had protective antibody titres 28 days after oral vaccination. The seroconversion rate in young piglets (n = 44, younger than 12 weeks) was 64%. Based on the results obtained we concluded that in an endemic situation where usual control measures (stamping out, zoning with restrictive measures, parenteral vaccination, etc.) may prove to be insufficient, a systematic vaccination based on the use of oral vaccine can be an appropriate tool for an improved CSF control in backyard production systems.

Abstract. This study aims to characterise the rainfall exceptionality and the meteorological context of the 20 February 2010 flash-floods in Madeira (Portugal). Daily and hourly precipitation records from the available rain-gauge station networks are evaluated in order to reconstitute the temporal evolution of the rainstorm, as its geographic incidence, contributing to understand the flash-flood dynamics and the type and spatial distribution of the associated impacts. The exceptionality of the rainstorm is further confirmed by the return period associated with the daily precipitation registered at the two long-term record stations, with 146.9 mm observed in the city of Funchal and 333.8 mm on the mountain top, corresponding to an estimated return period of approximately 290 yr and 90 yr, respectively. Furthermore, the synoptic associated situation responsible for the flash-floods is analysed using different sources of information, e.g., weather charts, reanalysis data, Meteosat images and radiosounding data, with the focus on two main issues: (1) the dynamical conditions that promoted such anomalous humidity availability over the Madeira region on 20 February 2010 and (2) the uplift mechanism that induced deep convection activity.

Abstract. A climatology of cyclones with a focus on their relation to wind storm tracks in the Mediterranean region (MR) is presented. Trends in the frequency of cyclones and wind storms, as well as variations associated with the North Atlantic Oscillation (NAO), the East Atlantic/West Russian (EAWR) and the Scandinavian variability pattern (SCAND) are discussed. The study is based on the ERA40 reanalysis dataset. Wind storm tracks are identified by tracking clusters of adjacent grid boxes characterised by extremely high local wind speeds. The wind track is assigned to a cyclone track independently identified with an objective scheme. Areas with high wind activity – quantified by extreme wind tracks – are typically located south of the Golf of Genoa, south of Cyprus, southeast of Sicily and west of the Iberian Peninsula. About 69% of the wind storms are caused by cyclones located in the Mediterranean region, while the remaining 31% can be attributed to North Atlantic or Northern European cyclones. The North Atlantic Oscillation, the East Atlantic/West Russian pattern and the Scandinavian pattern all influence the amount and spatial distribution of wind inducing cyclones and wind events in the MR. The strongest signals exist for the NAO and the EAWR pattern, which are both associated with an increase in the number of organised strong wind events in the eastern MR during their positive phase. On the other hand, the storm numbers decrease over the western MR for the positive phase of the NAO and over the central MR during the positive phase of the EAWR pattern. The positive phase of the Scandinavian pattern is associated with a decrease in the number of winter wind storms over most of the MR. A third of the trends in the number of wind storms and wind producing cyclones during the winter season of the ERA40 period may be attributed to the variability of the North Atlantic Oscillation.

This paper presents a critical and quantitative analysis of the influence of the Power Quality in grid connected solar photovoltaic microgeneration installations. First are introduced the main regulations and legislation related with the solar photovoltaic microgeneration, in Portugal and Europe. Next are presented Power Quality monitoring results obtained from two residential solar photovoltaic installations located in the north of Portugal, and is explained how the Power Quality events affect the operation of these installations. Afterwards, it is described a methodology to estimate the energy production losses and the impact in the revenue caused by the abnormal operation of the electrical installation. This is done by comparing the amount of energy that was injected into the power grid with the theoretical value of energy that could be injected in normal conditions. The performed analysis shows that Power Quality severally affects the solar photovoltaic installations operation. The losses of revenue in the two monitored installations M1 and M2 are estimated in about 27% and 22%, respectively. ; CT - Fundação para a Ciência e Tecnologia within scope of the project : PEst- ...

Regional climate predictions for the next decade are gaining importance, as this period falls within the planning horizon of politics, economy, and society. The potential predictability of climate indices or extremes at the regional scale is of particular interest. The German MiKlip project ("mid‐term climate forecast") developed the first regional decadal prediction system for Europe at 0.44° resolution, based on the regional model COSMO‐CLM using global MPI‐ESM simulations as boundary conditions. We analyse the skill of this regional system focussing on extremes and user‐oriented variables. The considered quantities are related to temperature extremes, heavy precipitation, wind impacts, and the agronomy sector. Variables related to temperature (e.g., frost days, heat wave days) show high predictive skill (anomaly correlation up to 0.9) with very little dependence on lead‐time, and the skill patterns are spatially robust. The skill patterns for precipitation‐related variables (e.g., heavy precipitation days) and wind‐based indices (like storm days) are less skilful and more heterogeneous, particularly for the latter. Quantities related to the agronomy sector (e.g., growing degree days) show high predictive skill, comparable to temperature. Overall, we provide evidence that decadal predictive skill can be generally found at the regional scale also for extremes and user‐oriented variables, demonstrating how the utility of decadal predictions can be substantially enhanced. This is a very promising first step towards impact‐related modelling at the regional scale and the development of individual user‐oriented products for stakeholders.