Copies of author's previously published articles inserted / Bibliography: leaves 219-226 / xvi, 22l leaves, [5] leaves of plates : ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Mawson Institute for Antarctic Research, 1990

Thesis (doctoral)--Rijksuniversiteit Groningen, 2001. / "Stellingen" and errata slip inserted at front. Includes bibliographical references (p. 181-190. [Author's] Publications: p. 191-193).

Thesis (M.Sc.)(Meteorology)--University of Pretoria, 2007. / Includes summary. Includes bibliographical references. Available on the Internet via the World Wide Web.

No description available.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-11-08T11:09:05Z No. of bitstreams: 1 ROBSON BATISTA DE SOUSA - DISSERTAÇÃO (PPGFísica) 2012.pdf: 22073508 bytes, checksum: 07991b4cdb0e710b093893fcc69708ec (MD5) / Made available in DSpace on 2018-11-08T11:09:05Z (GMT). No. of bitstreams: 1 ROBSON BATISTA DE SOUSA - DISSERTAÇÃO (PPGFísica) 2012.pdf: 22073508 bytes, checksum: 07991b4cdb0e710b093893fcc69708ec (MD5) Previous issue date: 2012-05-16 / Medidas de ventos e de temperatura obtidas por radar meteórico (SKiYMET) em São João do Cariri-PB (7, 4◦S) e em Cachoeira Paulista-SP (22, 7◦S) foram utilizadas para investigar a oscilação de 6, 5 dias na região mesosférica. Os resultados das análises dos dados de vento e de temperatura revelaram a presença da onda de 6, 5 dias em ambas as localidades, em que as atividades máximas ocorreram durante os meses de primavera austral. Os valores das amplitudes e dos comprimentos de onda vertical, determinados a partir das medidas de ventos, para São João do Cariri, foram superiores aos de Cachoeira Paulista. Em ambas as localidades foram verificadas uma modulação da onda de 6, 5 dias pela Oscilação Semi-Anual (SAO) na temperatura mesosférica. De um modo geral, tanto em São João do Cariri, quanto em Cachoeira Paulista, as atividades máximas da onda de 6, 5 dias foram registradas durante a fase para oeste da Oscilação Quase-Bienal (QBO). Entretanto, o conjunto de dados utilizados neste trabalho não são suficientes para estabelecer uma relação conclusiva dos efeitos da QBO na atividade da onda de 6, 5 dias. Em geral, os parâmetros físicos da onda de 6, 5 dias obtidos neste trabalho são compatíveis com os reportados em outras localidades. / Measurements of wind and temperature obtained from SKiYMET meteor radars at São João do Cariri-PB (7.4◦S) and Cachoeira Paulista (22.7◦S) were used to investigate the 6.5-day oscillations in the mesospheric region. The wind and temperature data analysis results revealed the presence of the 6.5-day waves at both sites, in which the maximum activities have occurred during the austral spring months. The amplitudes and vertical wavelength values, estimated from the wind vertical structure phase delay, for São João do Cariri were longer than for Cachoeira Paulista. For the first time, has been observed for both sites that the 6.5-day wave activities display a semi-annual modulation (SAO) in the meteor temperature. In general, the maximum activities of the 6.5-day waves took place during westward QBO wind phase. However, the data series used in this study are not enough to establish a reliable QBO modulation of the 6.5-day wave. In general, the 6.5-day wave parameters obtained in this work are consistent with those reported for other sites.

The production of energy alternative can provide economic development and employment opportunities, especially in agricultural areas. The work seeks as main objectives the rising and the statistical treatment of the data of winds of the State of Sergipe. As specific objectives still seek the simulation of the annual energy generated starting from an aerogenerating for rural use, and the simulation of the amount of water capable of being pumped through a low cost bomb and potency.The values of the meteorological variables were obtained in stations automatic meteorological and you stipulate distributed in the State. These elements served as base for rising of the medium speeds of wind, the schedules of better use of the system aeolian. The statistical treatment for determination of the behavior of the winds in the researched municipal districts was beacon in the calculation of averages, variances, distribution of frequencies and of the function of distribution of probability Rayleigh, case peculiar of the distribution Weibull, thoroughly diffused in studies of potential aeolian. These analyses allowed to extract all the information starting from the obtained gross data of the stations and they were simulate in the software Statistica 7.0. The period of the day in that were registered to largest medium speeds it is the period of the afternoon understood between 12:00 hours and 18:00 hours for all the researched municipal districts, being this period chosen for the simulations in software. As the use and simulations of the system aeolian to assist the needs of agricultural electric feeding were used as model for the tests a turbine aeolian with potency of 400 W, simulated in the Software EOLOSOFT of NUTEMA-PUCRS and all the municipal districts presented conditions of wind speed capable to supply the essential provisioning, mainly in what it tells respect the provisioning of water for consumption and irrigation. It was not white of this work the study of economic viability of the system aeolian in relation to the cost of the turbine and accessories of the system for maker. / A produção de energia alternativa pode prover desenvolvimento econômico e oportunidades de emprego, especialmente em áreas Rurais. O trabalho visa como objetivos principais o levantamento e o tratamento estatístico dos dados de ventos do Estado de Sergipe. Como objetivos específicos visa ainda a simulação da energia anual gerada a partir de um aerogerador para uso rural, e a simulação da quantidade de água capaz de ser bombeada através de uma bomba de baixo custo e potência. Os valores das variáveis meteorológicas foram obtidos em estações agrometeorológicas automáticas e convencionais distribuídas no Estado. Estes elementos serviram de base para levantamento das velocidades médias de vento, os horários de melhor aproveitamento do sistema eólico. O tratamento estatístico para determinação do comportamento dos ventos nos municípios pesquisados balizou-se no cálculo de médias, variâncias, distribuição de freqüências e da função de distribuição de probabilidade Rayleigh, caso particular da distribuição Weibull, amplamente difundida em estudos de potencial eólico. Estas análises permitiram extrair todas as informações a partir dos dados brutos obtidos das estações e foram simuladas no software Statistica 7.0. O período do dia em que foram registradas a maiores velocidades médias é o período da tarde compreendido entre 12:00 horas e 18:00 horas para todos os municípios pesquisados, sendo este período escolhido para as simulações em software. Quanto a utilização e simulações do sistema eólico para atender as necessidades de alimentação elétrica rural foi utilizado como modelo para os testes uma turbina eólica com potência de 400 W, simulada no Software EOLOSOFT do NUTEMA-PUCRS e todos os municípios apresentaram condições de velocidade de vento capaz de fornecer o abastecimento essencial, principalmente no que diz respeito a abastecimento de água para consumo e irrigação. Não foi alvo deste trabalho o estudo de viabilidade econômica do sistema eólico em relação ao custo da turbina e acessórios do sistema por fabricante.

Tendo em vista o crescente investimento em atividades economicamente importantes nas zonas costeiras, tal como a produção petrolífera brasileira e o crescimento na atividade portuária e esforço de pesca, a compreensão adequada dos fenômenos oceanográficos e meteorológicos sobre tais zonas é de grande valia para as operações desses setores. Os ventos representam um importante parâmetro para análise nesse sentido, sendo a principal fonte de energia para a geração de ondas de gravidade nos oceanos, e determinantes na caracterização de condições severas tempo. Uma série de estudos foram desenvolvidos nos últimos anos envolvendo a análise do comportamento dos extremos de ondas sobre a região do Oceano Atlântico Sul, de acordo com o crescimento da demanda por tais informações pelo setor industrial. No entanto, há poucos registros de estudos que caracterizem os extremos de intensidade de vento sobre essa região. E, em nenhum desses trabalhos, a separação direcional do vento extremo e seus fenômenos causadores foram levados em consideração. Dessa forma, o presente trabalho visa atender diretamente a necessidade por trabalhos nesse sentido para a região do Oceano Atlântico Sul, buscando oferecer uma análise dos campos de ventos extremos direcionalmente segregados, através de dados do projeto de reanálise \\textit{NCEP/NCAR Reanalysis I} e de resultados de uma simulação numérica com o modelo BRAMS. A tais conjuntos de dados foi aplicada a metodologia de análise de extremos \\textit{Peaks Over Threshold} (POT), que trata do ajuste dos excessos acima de um limiar estabelecido a uma distribuição conhecida, a Distribuição Generalizada de Pareto (Generalized Pareto Distribution - GPD). E, a partir disso, construir mapas com os valores extremos de retorno para longos períodos. Tais parâmetros são muito importantes na predição de eventos extremos e no refinamento de simulações de longo período. Os extremos relacionados aos fenômenos em larga escala, dados pelos campos do NCEP, em conjunto com o maior detalhamento em mesoescala, dado pelo BRAMS, refletiram diretamente no comportamento dos valores extremos de retorno. Para todas as direções do vento analisadas, observaram-se feições mais refinadas dos extremos de retorno para os resultados com a simulação do BRAMS, principalmente nas zonas costeiras. Essas feições, principalmente àquelas ao sul e sudeste do Oceano Atlântico Sul, tiveram seus valores potencializados em zonas já conhecidas na bibliografia pela grande incidência de eventos altamente energéticos. / Given the growing investment in important economic activities in coastal areas, such as oil and gas exploitation, harbor activities and increasing fishing effort, the proper understanding of oceanographic and meteorological phenomena over such areas has great value to the operations of such sectors. The winds are an important parameter for analysis in this context, being the main source of energy for gravity waves generation in the ocean, and determining the characterization of severe weather conditions. A number of studies have been developed in recent years involving the behavior of extreme waves over the South Atlantic Ocean region, given the rowing demand for such information by industrial sectors. However, there are few records of studies that characterize the extremes of wind speed fields over this region. And, in none of these works, the direction of the extreme wind and meteorological phenomenon associated were considered. Thus, this paper aims to address directly the need for work in this context for the South Atlantic Ocean region, seeking to offer an analysis of extreme wind fields directionally separated, through data from the NCEP/NCAR Reanalysis 1 and results from a numerical simulation with BRAMS. The Peaks Over Threshold (POT), which deals with the adjustment of the excesses above a threshold to the Generalized Pareto Distribution (GPD), was applied to both datasets. And from that, maps with the extreme return values have been developed for long return periods. These parameters are very important in predicting extreme events and refinement of long-period simulations. Extreme winds related to the large scale phenomena, represented by NCEP fields, in conjunction with the greater mesoscale detail, given by the BRAMS simulation, directly reflected in the behavior of extreme return values. For all wind directions analyzed, there were more refined features of the extremes return levels given by the BRAMS simulation, especially in coastal areas. These features, notably those in the south and southeast of the South Atlantic Ocean, values were strengthened in areas already known in the literature for the high incidence of energetic events.

Orientador: Luci Hidalgo Nunes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-20T15:46:52Z (GMT). No. of bitstreams: 1 Silva_ClaudiaMariaPereirada_M.pdf: 3643925 bytes, checksum: 3841cf22ec24e7ad3eab84250d7ade8d (MD5) Previous issue date: 2011 / Resumo: O acelerado processo de urbanização do século XX contribuiu para a maior ocupação de áreas de risco, principalmente por população de baixa renda. Isso trouxe aumento de suas vulnerabilidades a problemas advindos de fenômenos atmosféricos, especialmente nos centros urbanos,o que ampliou a segregação socioespacial em vários municípios brasileiros. Esse quadro se manifesta não apenas nos grandes centros urbanos, mas também nas cidades mediase pequenas. É o caso da área urbana de Atibaia-SP, que é atingida por inundações e problemas a partir do registro de ventos fortes, o que motivou este estudo, que visa correlacionar, de forma qualitativa e quantitativa, os eventos deflagradores de problemas ambientais (precipitação e ventos) e suas consequências no meio urbano (alagamentos, inundações, quedas de energia, danos estruturais etc.). Os resultados serão apresentados e discutidos em termos de suas tendências espaciais e temporais, cobrindo o período de 1960 a 2007. Espera-se subsidiar o poder público, notadamente as ações da Defesa Civil de Atibaia / Abstract: The accelerated process of urbanization of the twentieth century contributed to increase the occupation of risk areas, mainly by the low income population. This has increased their vulnerability to problems arising from atmospheric phenomena, especially in urban centers, which widened the sociospatial segregation in several municipalities. This framework is reflected not only in urban centers but also in medium and small cities. This is the case of the urban area of Atibaia-SP, which has been hit with floodings and strong winds, which motivated this study, that aims to correlate, both qualitatively and quantitatively events that trigger environmental problems (precipitation and wind) and their consequences in urban areas (flooding, floods, power shortages, structural damage etc.). The results will be presented and discussed in terms of their spatial and temporal trends, covering the period 1960 to 2007. It is expected to subsidize governmental actions, especially the Civil Defense of Atibaia / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia

Surface wind speeds are an important and revealing component of the structure of tropical cyclones (TCs). To understand the asymmetric structure of surface winds in TCs associated with differences in formation region, environmental wind shear, storm forward motion, and TC strength and intensification, a twelve year database of satellite scatterometer data are utilized to produce composite total wind speed and Fourier-derived, low wavenumber analyses. A quantified asymmetry is determined as a function of TC intensity and reveals the tropical storms are influenced by wind shear at all TC-centric radii but only for areas away from the radius of maximum wind in hurricanes. Additionally, an increase of absolute angular momentum flux has a preference for the downshear-right quadrant, and the low wavenumber maximum develops downwind of this momentum transport. Further evaluation of the asymmetric structure with respect to wind shear’s relation to motion and impacts during TC intensity change are also considered. A composite rapid intensification event is produced and compared to overlapping satellite rain estimates. Results indicate that the TC becomes more symmetric during intensification and the phase of the maximum asymmetry rotates from a downshear-left direction to upshear-left direction after the intensification slows. The rain or convective maximum is generally located upwind of the surface wind maximum at the early stages of intensification and is coincident with the region of large angular momentum transport, which supports the idea that the surface wind asymmetry is likely a consequence of convective or other processes. Using data from a regional TC model, it is also determined that the scatterometer data are useful for model verification of tropical storms and non-major hurricanes and performs similar to or better than the standard tool at forecast lead times up to 60 hours. Preliminary comparisons of model-derived surface wind asymmetry relative to rain generally confirm the observational results.

Gap, outflow, or Squamish wind, is the cold low level seaward flow of air through fjords which dissect the coastal mountain barrier of northwestern North America. These flows, occurring mainly during winter, can be strong, threatening safety, economic activity and comfort. Howe Sound gap winds were studied using a combination of observations and several types of models. Observations of winds in Howe Sound showed that gap wind strength varied considerably along the channel, across the channel and vertically. Generally, winds increase down the channel, are strongest along the eastern side, and are below 1000 m depth. Observations were unable to answer all questions about gap winds due to data sparseness, particularly in the vertical direction. Therefore, several modelling approaches were used. The modelling began with a complete 3-dimensional quasi-Boussinesq model (CSURAMS) and ended with the creation and testing of models which are conceptually simpler, and more easily interpreted and manipulated. A gap wind simulation made using RAMS was shown to be mostly successful by statistical evaluation compared to other mesoscale simulations, and by visual inspection of the fields. The RAMS output, which has very high temporal and spatial resolution, provided much additional information about the details of gap flow. In particular, RAMS results suggested a close analogy between gap wind and hydraulic channel flow, with hydraulic features such as supercritical flow and hydraulic jumps apparent. These findings imply gap wind flow could potentially be represented by much simpler models. The simplest possible models containing pressure gradient, advection and friction but not incorporating hydraulic effects, were created, tested, and found lacking. A hydraulic model, which in addition incorporates varying gap wind height and channel geometry, was created and shown to successfully simulate gap winds. Force balance analysis from RAMS and the hydraulic model showed that pressure gradient and advection are the most important forces, followed by friction which becomes an important force in fast supercritical flow. The sensitivity of gap wind speed to various parameters was found from sensitivity tests using the hydraulic model. Results indicated that gap wind speed increases with increasing boundary layer height and speed at the head of channel, and increasing synoptic pressure gradient. Gap wind speed decreases with increasing friction, and increasing boundary layer height at the seaward channel end. Increasing temperature dilterences between the cold gap wind air and the warmer air aloft was found to increase the variability of the flow — higher maximum but lower mean wind speeds. / Arts, Faculty of / Geography, Department of / Graduate