Dowscaling estocástico para extremos climáticos via interpolação espacial

Present day weather forecast models usually cannot provide realistic descriptions of local and particulary extreme weather conditions. However, for lead times of about a small number of days, they provide reliable forecast of the atmospheric circulation that encompasses the subscale processes leading to extremes. Hence, forecasts of extreme events can only be achieved through a combination of dynamical and statistical analysis methods, where a stable and significant statistical model based on prior physical reasoning establishes posterior statistical-dynamical model between the local extremes and the large scale circulation. Here we present the development and application of such a statistical model calibration on the besis of extreme value theory, in order to derive probabilistic forecast for extreme local temperature. The dowscaling applies to NCEP/NCAR re-analysis, in order to derive estimates of daily temperature at Brazilian northeastern region weather stations

Indicador de vulnerabilidade agropecuária a extremos climáticos para o nordeste do Brasil

The effects of climate change on human societies have become the focus of many researchers for their research. Understanding weather patterns (circulation of the atmosphere, precipitation, temperature) is essences for predicting extreme weather, but analyze how these extreme events act in our society and look for ways to reduce the impact caused by these events is the great challenge. Using a concept very in the humanities and social sciences to understand these impacts and the adaptation of the society's vulnerability. The objective of this work is to develop and apply a methodology for evaluating fining scale and quantify the vulnerability of the Brazilian Northeast to climatic extremes, developing a methodology that combines aspects of vulnerability to drought, as well as socioeconomic and climatic indicators used to assess exposure, ability to adaptation and the sensitivity of geographical microregions of the region. The assessment of the susceptibility or degree of exposure to risk is the regional using the SPI (Standardized Precipitation Index) by the degree of magnitude dried (MD), the rate of precipitation such as PCD (Precipitation Concentration Degree) and PCP (Precipitation Period Concentration) helped characterize and regional climatology, these indices showed satisfactory results in the pilot study of Rio Grande do Norte to assess the degree of exposure to drought. Regarding sensitivity agricultural / livestock multivariate statistical technique to factor analysis showed acceptable results for the proposed model using data for the period 1990-1999 (P1). The application of the analysis of vulnerability considering the adaptive capacity, as the adaptive disability have almost similar results with much of the region's vulnerability to extreme south of Bahia state as a part of the semiarid region has a degree of vulnerability among moderate and mean

Modelos de dispersão para extremos de precipitação. Estudo de caso: o nordeste do Brasil

In this thesis used four different methods in order to diagnose the precipitation extremes on Northeastern Brazil (NEB): Generalized Linear Model s via logistic regression and Poisson, extreme value theory analysis via generalized extre me value (GEV) and generalized Pareto (GPD) distributions and Vectorial Generalized Linea r Models via GEV (MVLG GEV). The logistic regression and Poisson models were used to identify the interactions between the precipitation extremes and other variables based on the odds ratios and relative risks. It was found that the outgoing longwave radiation was the indicator variable for the occurrence of extreme precipitation on eastern, northern and semi arid NEB, and the relative humidity was verified on southern NEB. The GEV and GPD distribut ions (based on the 95th percentile) showed that the location and scale parameters were presented the maximum on the eastern and northern coast NEB, the GEV verified a maximum core on western of Pernambuco influenced by weather systems and topography. The GEV and GPD shape parameter, for most regions the data fitted by Weibull negative an d Beta distributions (ξ < 0) , respectively. The levels and return periods of GEV (GPD) on north ern Maranhão (centerrn of Bahia) may occur at least an extreme precipitation event excee ding over of 160.9 mm /day (192.3 mm / day) on next 30 years. The MVLG GEV model found tha t the zonal and meridional wind components, evaporation and Atlantic and Pacific se a surface temperature boost the precipitation extremes. The GEV parameters show the following results: a) location ( ), the highest value was 88.26 ± 6.42 mm on northern Maran hão; b) scale ( σ ), most regions showed positive values, except on southern of Maranhão; an d c) shape ( ξ ), most of the selected regions were adjusted by the Weibull negative distr ibution ( ξ < 0 ). The southern Maranhão and southern Bahia have greater accuracy. The level period, it was estimated that the centern of Bahia may occur at least an extreme precipitatio n event equal to or exceeding over 571.2 mm/day on next 30 years.

Influência de eventos hidrológicos extremos na qualidade da água de reservatórios na região tropical semiárida

Reservoirs are artificial ecosystems, intermediate between rivers and lakes, with diferent morphological and hydrological characteristics that can provide many important benefits to society. However, the use of this water for human consumption, watering livestock, leisure, irrigated agricultural production and pisciculture development, directly influence the increase loading of nutrients to aquatic environments and contribute to acceleration of eutrophication. Furthermore, global climate models are predicting a higher occurrence of extreme events such as floods and severe droughts, which will create hydrological stresses in lakes. In the semiarid northeast we can see the occurrence of these events, the drought of the years 2012, 2013 and 2014 was the worst drought in 60 years, according to the National Water Agency (ANA). Thus, this study aimed to evaluate the quality of the semiarid tropical water sources, identifying temporal patterns in periods with extreme hydrological events (floods and severe droughts). The study results showed that Gargalheiras and Cruzeta reservoirs presented significative changes in the limnological variables between rain and severe drought periods, with better appearance and in the most of the water quality variables in the rainy season and higher nutrientes concentrations and high electrical conductivity values in severe season, indicating decay of its quality. However, we found diferent behaviors between the reservoirs in severe drought. While Gargalheiras showed a typical behavior of the region, with high concentrations of algal biomass, indicating the worsening eutrophication, Cruzeta demonstrated a colapse in the total phytoplankton biomass, evidenced by the decrease in chla concentrations. This fact occurred because the low depth and proximity with the sediment facilited the inorganic solids resuspension and, consequently, resulted in turbid water column and light by limitation. In addition, the different behaviors between the reservoirs indicate that the responses of these environments problems such as extreme events must take into account factors such the region climate, size, depth of the reservoir and the basin characteristics.

Efeito da idade materna sobre os resultados perinatais

Objetivo: analisar a relação entre a idade materna e a ocorrência de resultados perinatais adversos na população do Rio Grande do Norte. Métodos: foram analisados os registros oficiais de 57.088 nascidos vivos no Estado do Rio Grande do Norte no ano de 1997. Os dados foram obtidos do Sistema de Informação sobre Nascidos Vivos do Ministério da Saúde. A população estudada foi dividida em Grupos I, II e III, segundo a faixa etária materna: 10 a 19, 20 a 34 e 35 anos ou mais, respectivamente. As variáveis analisadas foram: duração da gestação, peso ao nascer e tipo de parto. A análise estatística foi realizada utilizando-se o teste c2. Resultados: observamos uma maior incidência de parto pré-termo no Grupo I (4,3 %), em comparação ao Grupo II (3,7%) (p = 0,0028). A taxa de cesariana foi menor nos Grupos I e III, em comparação ao Grupo II (p<0,0001). Evidenciamos freqüência significativamente maior de recém-nascidos de baixo peso nos Grupos I (8,4%) e III (8,3%), quando comparados ao Grupo II (6,5%) (p<0,0001). Conclusões: a gravidez nos extremos da vida reprodutiva esteve associada com maior freqüência de parto pré-termo e baixo peso ao nascer, entretanto, com relação ao tipo de parto, foi observada maior freqüência de parto normal do que no grupo de gestantes com idade entre 20 e 34 anos

Atenuação de ruídos coerentes utilizando decomposição em modos empíricos

The seismic processing technique has the main objective to provide adequate picture of geological structures from subsurface of sedimentary basins. Among the key steps of this process is the enhancement of seismic reflections by filtering unwanted signals, called seismic noise, the improvement of signals of interest and the application of imaging procedures. The seismic noise may appear random or coherent. This dissertation will present a technique to attenuate coherent noise, such as ground roll and multiple reflections, based on Empirical Mode Decomposition method. This method will be applied to decompose the seismic trace into Intrinsic Mode Functions. These functions have the properties of being symmetric, with local mean equals zero and the same number of zero-crossing and extremes. The developed technique was tested on synthetic and real data, and the results were considered encouraging

Metagenômica: busca de novos genes envolvidos com a biodegradação de hidrocarbonetos

Industrial activities, oil spills and its derivatives, as well as the incomplete combustion of fossil fuels have caused a great accumulation of hydrocarbons in the environment. The number of microorganisms on the planet is estimated at 1030 and prokaryotes the most abundant. They colonized diverse environments for thousands of years, including those considered extreme and represent an untapped source of metabolic and genetic diversity with a large biotechnological potential. It is also known that certain microorganisms have the enzymatic capacity to degrade petroleum hydrocarbons and, in many ecosystems, there is an indigenous community capable of performing this function. The metagenomic has revolutionized the microbiology allowing access uncultured microbial communities, being a powerful tool for elucidation of their ecological functions and metabolic profiles, as well as for identification of new biomolecules. Thus, this study applied metagenomic approaches not only for functional selection of genes involved in biodegradation and emulsification processes of the petroleum-derived hydrocarbons, but also to describe the taxonomic and metabolic composition of two metagenomes from aquatic microbiome. We analyzed 123.116 (365 ± 118 bp) and 127.563 sequences (352 ± 120 bp) of marine and estuarine metagenomes, respectively. Eight clones were found, four involved in the petroleum biodegradation and four were able to emulsify kerosene indicating their abilities in biosurfactants synthesis. Therefore, the metagenomic analyses performed were efficient not only in the search of bioproducts of biotechnological interest and in the analysis of the functional and taxonomic profile of the metagenomes studied as well

Estudo estatístico sobre eventos de precipitação intensa no nordeste do Brasil

The Northeast of Brazil (NEB) shows high climate variability, ranging from semiarid regions to a rainy regions. According to the latest report of the Intergovernmental Panel on Climate Change, the NEB is highly susceptible to climate change, and also heavy rainfall events (HRE). However, few climatology studies about these episodes were performed, thus the objective main research is to compute the climatology and trend of the episodes number and the daily rainfall rate associated with HRE in the NEB and its climatologically homogeneous sub regions; relate them to the weak rainfall events and normal rainfall events. The daily rainfall data of the hydrometeorological network managed by the Agência Nacional de Águas, from 1972 to 2002. For selection of rainfall events used the technique of quantiles and the trend was identified using the Mann-Kendall test. The sub regions were obtained by cluster analysis, using as similarity measure the Euclidean distance and Ward agglomerative hierarchical method. The results show that the seasonality of the NEB is being intensified, i.e., the dry season is becoming drier and wet season getting wet. The El Niño and La Niña influence more on the amount of events regarding the intensity, but the sub-regions this influence is less noticeable. Using daily data reanalysis ERAInterim fields of anomalies of the composites of meteorological variables were calculated for the coast of the NEB, to characterize the synoptic environment. The Upper-level cyclonic vortex and the South atlantic convergene zone were identified as the main weather systems responsible for training of EPI on the coastland

Modelagem estocástica do índice de radiação ultravioleta na costa leste do nordeste do Brasil

The increase in ultraviolet radiation (UV) at surface, the high incidence of non-melanoma skin cancer (NMSC) in coast of Northeast of Brazil (NEB) and reduction of total ozone were the motivation for the present study. The overall objective was to identify and understand the variability of UV or Index Ultraviolet Radiation (UV Index) in the capitals of the east coast of the NEB and adjust stochastic models to time series of UV index aiming make predictions (interpolations) and forecasts / projections (extrapolations) followed by trend analysis. The methodology consisted of applying multivariate analysis (principal component analysis and cluster analysis), Predictive Mean Matching method for filling gaps in the data, autoregressive distributed lag (ADL) and Mann-Kendal. The modeling via the ADL consisted of parameter estimation, diagnostics, residuals analysis and evaluation of the quality of the predictions and forecasts via mean squared error and Pearson correlation coefficient. The research results indicated that the annual variability of UV in the capital of Rio Grande do Norte (Natal) has a feature in the months of September and October that consisting of a stabilization / reduction of UV index because of the greater annual concentration total ozone. The increased amount of aerosol during this period contributes in lesser intensity for this event. The increased amount of aerosol during this period contributes in lesser intensity for this event. The application of cluster analysis on the east coast of the NEB showed that this event also occurs in the capitals of Paraiba (João Pessoa) and Pernambuco (Recife). Extreme events of UV in NEB were analyzed from the city of Natal and were associated with absence of cloud cover and levels below the annual average of total ozone and did not occurring in the entire region because of the uneven spatial distribution of these variables. The ADL (4, 1) model, adjusted with data of the UV index and total ozone to period 2001-2012 made a the projection / extrapolation for the next 30 years (2013-2043) indicating in end of that period an increase to the UV index of one unit (approximately), case total ozone maintain the downward trend observed in study period

Família, aluno e professor: as forças tipológicas da educação básica na região metropolitana de Natal

This work was developed in the research line: "The habitus of study: builder of a new reality in the basic education of metropolitan area Natal" which is being developed with the support of CAPES by the Centre for Education. Acts, especially the problem of academic performance of students in basic education of the public in the Metropolitan Region of Natal (RMN). Thus, the aim of this paper is to construct a typology of students in the 9th year of basic education, attending the public schools (state or municipal) of MRN, 2009, and assess, according to these profiles, what personal characteristics student and their families: economic, social and cultural capital as well as teaching practices create environments capable of favoring a good educational development as measured by the performance obtained in the assessments in mathematics and English language. The data used were provided through the microdata Brazil Exam 2009 held by INEP. We used the methods Grade of Membership (GoM) for construction of profiles relevance of students according to the characteristics already mentioned. With these profiles was verified, which were effectively generating good performance in school curriculum components evaluated. The findings indicate that students belonging to the profile considered good environment, able to achieve better school performance both in Portuguese as in Mathematics, compared to the extreme profiles and adverse deficit

Uma fundamentação para sinais e sistemas intervalares

In this work we use Interval Mathematics to establish interval counterparts for the main tools used in digital signal processing. More specifically, the approach developed here is oriented to signals, systems, sampling, quantization, coding and Fourier transforms. A detailed study for some interval arithmetics which handle with complex numbers is provided; they are: complex interval arithmetic (or rectangular), circular complex arithmetic, and interval arithmetic for polar sectors. This lead us to investigate some properties that are relevant for the development of a theory of interval digital signal processing. It is shown that the sets IR and R(C) endowed with any correct arithmetic is not an algebraic field, meaning that those sets do not behave like real and complex numbers. An alternative to the notion of interval complex width is also provided and the Kulisch- Miranker order is used in order to write complex numbers in the interval form enabling operations on endpoints. The use of interval signals and systems is possible thanks to the representation of complex values into floating point systems. That is, if a number x 2 R is not representable in a floating point system F then it is mapped to an interval [x;x], such that x is the largest number in F which is smaller than x and x is the smallest one in F which is greater than x. This interval representation is the starting point for definitions like interval signals and systems which take real or complex values. It provides the extension for notions like: causality, stability, time invariance, homogeneity, additivity and linearity to interval systems. The process of quantization is extended to its interval counterpart. Thereafter the interval versions for: quantization levels, quantization error and encoded signal are provided. It is shown that the interval levels of quantization represent complex quantization levels and the classical quantization error ranges over the interval quantization error. An estimation for the interval quantization error and an interval version for Z-transform (and hence Fourier transform) is provided. Finally, the results of an Matlab implementation is given

Análise da precipitação no semi-árido potiguar

The semiarid rainfall regime is northeastern Brazil is highly variable. Climate processes associated with rainfall are complex and their effects may represent extreme situations of drought or floods, which can have adverse effects on society and the environment. The regional economy has a significant agricultural component, which is strongly influenced by weather conditions. Maximum precipitation analysis is traditionally performed using the intensity-duration-frequency (IDF) probabilistic approach. Results from such analysis are typically used in engineering projects involving hydraulic structures such as drainage network systems and road structures. On the other hand, precipitation data analysis may require the adoption of some kind of event identification criteria. The minimum inter-event duration (IMEE) is one of the most used criteria. This study aims to analyze the effect of the IMEE on the obtained rain event properties. For this purpose, a nine-year precipitation time series (2002- 2011) was used. This data was obtained from an automatic raingauge station, installed in an environmentally protected area, Ecological Seridó Station. The results showed that adopted IMEE values has an important effect on the number of events, duration, event height, mean rainfall rate and mean inter-event duration. Furthermore, a higher occurrence of extreme events was observed for small IMEE values. Most events showed average rainfall intensity higher than 2 mm.h-1 regardless of IMEE. The storm coefficient of advance was, in most cases, within the first quartile of the event, regardless of the IMEE value. Time series analysis using partial time series made it possible to adjust the IDF equations to local characteristics

O efeito do regime hidrológico do semiárido na composição de espécies durante dominância de cianobactérias em um reservatório tropical

The potentially toxic cyanobacterial blooms in water bodies are spread across the globe, resulting in the loss of water quality and adverse effects on human health. In arid and semiarid regions, the hydrologic regime characterized by an annual cycle of drought and rain, change the volume and the retention time of the reservoir. Such changes affect the limnological characteristics and causing changes in composition and biomass community of cyanobacteria. The reservoir Cruzeta (Zmax = 8.7 m) is a eutrophic water supply source located in the semiarid tropical (Northeast Brazil). Raised the hypothesis that the hydrological regime of semi-arid tropical is a determining factor in the availability of resources in eutrophic water sources, which influences the composition of dominant species of cyanobacteria. The aim of this study was to analyze the changes in biomass and species composition of cyanobacteria for two annual hydrological cycles and evaluate factors drivers. The study was divided into five distinct periods (dry 2010, rain 2011, dry 2011, rain 2012, dry 2012). The dominant group found in all periods was Cyanobacteria (99% of total biomass), which contributed to the low diversity. The filamentous species Cylindrospermopsis raciborskii was present at both points in almost every study. The colonial species Microcystis panniformis and Sphaerocavum brasiliensis dominated only in periods with lower volumes of water. The diatoms contribute more to the biomass during the period of severe drought. The point near the dam (P1) had phytoplankton biomass larger than the point near the tributary (P2). The dominant species of colonial cyanobacteria lasted until the overflow in P1, and P2 this dominance was until the first rains. The redundancy analysis indicated that physical factors such as light availability and water level were the main factors driving the seasonal succession of phytoplankton. The composition of phytoplankton in spring was alternated by species of filamentous cyanobacteria in conditions of poor stability of the water column, such as Cylindrospermopsis raciborskii, and colonial species under conditions of high stability of the water column, such as Microcystis panniformis and Sphaerocavum brasiliensis. The extremes of torrential rains and severe droughts, governed by the hydrological regime of the semi-arid region led to the availability of resources in the watershed, directing the spatial and temporal dynamics of phytoplankton in the reservoir Cruzeta

Cartografias do desejo em asfalto selvagem - engraçadinha, seus amores e seus pecados: humor, erotismo e o pornógrafo no romance rodrigueano

Trata-se nesta dissertação de estabelecer, partindo do pensamento contemporâneo francês da linha deleuziana e guattariana, sobretudo, uma analítica do desejo capaz de reconfigurar o romance de Nelson Rodrigues, Asfalto selvagem: Engraçadinha, seus amores e seus pecados, desterritorializá-lo em relação à tradição crítica e estética, fundada no paradigma realista-naturalista enraizado no pensamento literário brasileiro, especificamente no século XX. Movemo-nos por discussões sobre o autor e sobre o romance, empreendidas por Rolnik, interlocutora de Guattari, o qual está ligado aos novos paradigmas estéticos, à questão da produção de subjetividades, à micropolítica, às multiplicidades e às minorias. Buscamos contribuir para esse redimensionamento, colocando-nos na perspectiva cartográfica e rizomática para surpreender, em Asfalto, seus processos de subjetivação, incidindo sobre as singularidades selvagens, considerando os conceitos de Foucault, aplicados à construção literária enquanto espaço heterotópico, configurando a experiência do fora, como princípios estéticos. Veremos que as personagens, com foco em Engraçadinha, funcionam, como pequenas máquinas desejantes, Corpos sem Órgãos, moléculas desestabilizando as formações molares. Destarte, Nelson Rodrigues, na perspectiva da produção autoral, torna-se o pornógrafo, o literato iterador, como agenciador de uma palavra perversa, para além dos dogmas, da cena romantizada, originando, em sua poética, a revelação da obs-cena, a obscenidade, como crítica às instituições falidas. Trazemos, nesse sentido, referências de Bataille, quanto ao que na atividade estética se relaciona com o excedente da visão, relacionados ao espaço tático-ótico, concepção deleuziana referentes ao corpo-linguagem, pornografia, pornógrafo, narrativas abomináveis. Acompanhamo-nos, pois, dos conceitos da problemática da diferença e da alteridade, repercutindo na larvaridade, nas afecções, que abrem vias comunicantes com fenômenos extremos, atuantes em torno do mesmo e do outro, trazendo a rizomaticidade do mal e da monstruosidade para a construção estética de Asfalto selvagem, vistos sob a ótica de Bataille, Deleuze, Baudrillard, em ensaios que rompem o olhar estrutural em torno da obra e oferecem subsídios para a construção de uma cartografia outra, o território do ficcional, habitado por um povo por vir, na perspectiva tratada por Deleuze e por Blanchot

Formação estelar desencadeada pela colisão entre nuvens moleculares magnetizadas

We use a finite diference eulerian numerical code, called ZEUS 3D, to do simulations involving the collision between two magnetized molecular clouds, aiming to evaluate the rate of star formation triggered by the collision and to analyse how that rate varies depending on the relative orientations between the cloud magnetic fields before the shock. The ZEUS 3D code is not an easy code to handle. We had to create two subroutines, one to study the cloud-cloud collision and the other for the data output. ZEUS is a modular code. Its hierarchical way of working is explained as well as the way our subroutines work. We adopt two sets of different initial values for density, temperature and magnetic field of the clouds and of the external medium in order to study the collision between two molecular clouds. For each set, we analyse in detail six cases with different directions and orientations of the cloud magnetic field relative to direction of motion of the clouds. The analysis of these twelve cases allowed us to conform analytical-theoretical proposals found in the literature, and to obtain several original results. Previous works indicate that, if the cloud magnetic fields before the collision are orthogonal to the direction of motion, then a strong inhibition of star formation will occur during a cloud-cloud shock, whereas if those magnetic fields are parallel to the direction of motion, star formation will be stimulated. Our treatment of the problem confirmed numerically those results, and further allowed us to quantify the relative star forming efficiencies in each case. Moreover, we propose and analyse an intermediate case where the field of one of the clouds is orthogonal to the motion and the field of the other one is parallel to the motion. We conclude that, in this case, the rate at which the star formation occurs has a value also intermediate between the two extreme cases we mentioned above. Besides that we study the case in which the fields are orthogonal to the direction of the motion but, instead of being parallel to each other, they are anti-parallel, and we obtained for this case the corresponding variation of the star formation rate due to this alteration of the field configuration. This last case has not been studied in the literature before. Our study allows us to obtain, from the simulations, the rate of star formation in each case, as well as the temporal dependence of that rate as each collision evolves, what we do in detail for one of the cases in particular. The values we obtain for the rate of star formation are in accordance with those expected from the presently existing observational data