Four continuous high-resolution peat records for the Holocene have been reconstructed across a ~300km transect from Shebster in Caithness to Yell in the Shetland Isles. These records describe the nature and extent of North Atlantic climate changes inferred from indicators of storminess and minerogenic aeolian dust, and are supported by radiogenic isotope analysis, tephrochronology and radiocarbon dating. The environmental changes at all four sites displays a significant degree of synchrony in response to changes in the position of the polar front jet (PFJ) stream and the phase of the North Atlantic Oscillation (NAO). Bromine concentrations in the peat, derived from sea spray, are used to reconstruct storm frequency and storm intensity, and mire surface wetness is used as an indicator of longer-term climate shifts. The results suggest a strong link between positive phases of the NAO and storminess. Subtle differences between the bromine concentrations and the mire surface wetness suggest that high intensity but perhaps less frequent periods of storminess are not necessarily associated with a wetter climate. Atmospheric minerogenic dust concentrations are used to reconstruct large-scale climate changes across the wider North Atlantic region. The results suggest a sympathy between dust activity and periods of glacial advance and a negative index of the NAO. Radiogenic isotope analysis suggests that the smallest particles may originate from Iceland.

The phenomenon of climate change exists in a liminal state between denial and acceptance, past and future, theory and reality, problem and catastrophe, unfolding in the spaces between apparently stable forms. This thesis considers different temporalities emerging within this transition through a creative exploration of extreme weather and climatic events that seeks to foreground the idea of change itself. Research centers around the Florida Keys, a low lying archipelago that is widely expected to become uninhabitable in the next half century due to sea level rise, but only if the islands do not suffer a similar fate much sooner with the sudden arrival of a catastrophic hurricane. While most Keys residents are unconcerned about the growing reality of sea level rise, hurricanes are a constant threat generating a palpable atmosphere of anticipation and corresponding precaution. In resonance with this regular storm activity in the Florida Keys, the project also reflects on the coincidental occurrence of Hurricanes Irene (2011) and Sandy (2012), two errant and devastating storms that visited the northeastern United States over the course of this project and personally affected the author. Thus, extreme weather provides a material entry point into the complex and far-reaching event of climate change, offering an opportunity to theorize transition and to reflect on what might be creatively recuperated from cross currents of climate and catastrophe. In conclusion, the thesis proposes an ontology inspired by the unique reproductive strategy of the mangrove plant that has thickly and extensively colonized the coastline of southern Florida and through which events are understood to possess qualities of latency, accrual and distribution and to give rise to a future that is germinal, a present that is continuously resignified and a past that remains profoundly creative.

O ‘Parsley Massacre’ – o assassinato de haitianos que viviam na República Dominicana em 1937 – é o tema de The farming of bones (1998), escrito por Edwidge Danticat, que oferece ao leitor o testemunho ficcional de uma sobrevivente da violência do genocídio. De forma similar, em Solar storms (1995), Linda Hogan faz a descendente de um povo que foi massacrado a protagonista de uma busca pelo passado e pela história de seu povo. Ambos os romances empregam estratégias narrativas em busca da representação ficcional do trauma como experiência pessoal e coletiva, implicando o leitor na produção de sentido (CARUTH 1996; FREUD; 1920). É através do recordar e reviver o passado que os sujeitos traumatizados podem tentar compreender sua situação presente e reivindicar uma identidade para si mesmos (HALL, 2006). A revisão do passado, e precisamente de um passado silenciado, proporciona que as vozes de uma comunidade possam ser ouvidas e suas histórias trazidas à luz. Nesse estudo, eu busco investigar de que forma tais histórias são construídas, quais seus efeitos na superfície textual e suas implicações no empoderamento dos sujeitos. Além disso, investigo as conexões entre o corpo traumatizado e a mente, compreendendo o corpo como uma superfície histórica que recebe a inscrição da experiência humana (GROSZ, 1994). / The Parsley Massacre – the killing of Haitians living in the Dominican Republic in 1937 – is the theme of The farming of bones (1998), written by Edwidge Danticat, who offers the reader a fictional testimony of a survivor of the violence of genocide. Similarly, in Solar storms (1995), Linda Hogan makes the descendant of a massacred people the protagonist of a search for the past and her people’s history. Both novels employ narrative strategies for a fictional representation of trauma, as personal and collective experiences, implicating the reader in the production of meaning (CARUTH 1996; FREUD; 1920). It is by reliving and re-experiencing the past that traumatized subjects can make sense of their present condition and claim an identity for themselves (HALL, 2006). It is by revising the past, a historically silenced past, that the voices of a community can be heard and their stories brought out to light. In this study, I am also interested in how these stories are constructed, in what are their effects on the surface of the text and their implications in the empowering of subjects. Moreover, I investigate the connections between the traumatized body and the mind, understanding the body as an historical surface for the inscription of human experience (GROSZ, 1994).

Title: Convective storms and lower stratospheric moisture Author: Jindřich Šťástka Department: Department of Atmospheric Physics Supervisor: RNDr. Martin Setvák, CSc., Czech Hydrometeorological Institute Abstract: The primary focus of this thesis is to diagnose contributions to upper tropo- spheric and lower stratospheric (UTLS) water vapor from convective storms. The first parts of this work introduces two approaches used for a detection of lower stratospheric water vapor above convective storm tops - brightness temperature difference (BTD) technique and EOS MLS measurements. The BTD technique is based on brightness temperature difference between the water vapor absorp- tion and infrared window bands, assuming a thermal inversion above the cloud top level. The most frequently offered explanation of positive BTD values above convective storms is presence of warmer water vapor in the lower stratosphere. Furthermore, so called BTD anomalies were described and it was proposed an algorithm for objective detection of such BTD anomalies. Characteristics of pa- rameters describing BTD, BTD anomaly, infrared window brightness temperature were investigated during storms evolution on dataset of 320 storms from the area of Europe. The analysis of these characteristics proved highly probable conection between positive...

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This study presents a prototype of a deployable unit for automated surface weather observation, named Estação Mesomóvel, which is mounted on a tripod and portable in a small vehicle, allowing its installation in the path of oncoming convective storms. With a high frequency data sampling strategy, the Estação Mesomóvel is capable of monitoring adequately mesoscale surface features produced by convection. The challenges and solutions found during the conception of the prototype are discussed, as well as the results from the data comparison experiments conducted between the Estação Mesomóvel and an automated surface weather station from the operational network. The operation of the Estação Mesomóvel in storm interception mode is presented in the context of the weather analysis and forecasting strategies used, the deployment logistics, and the atmospheric data obtained in the field. Results from the analysis of the collected data showed the capability of the Estação Mesomóvel in sampling the evolution, at high frequency, of convective phenomena at the meso-g scale, such as gust fronts, cold pools, mesohighs and high precipitation rates, which are typically poorly represented by the synoptic-scale surface observing network. This investigation showed the feasibility of conducting storm interception in Brazil with the goal of collecting high-quality atmospheric data for scientific purposes. / Neste trabalho é apresentada a Estação Mesomóvel, que consiste no protótipo de uma unidade tática de observação meteorológica automática de superfície, montada sobre tripé e transportável em um veículo de pequeno porte, podendo assim ser instalada na trajetória de tempestades convectivas. Com sua amostragem em alta frequência, a Estação Mesomóvel é capaz de monitorar de maneira adequada circulações de mesoescala produzidas pela convecção. São apresentados os desafios e as soluções encontradas durante a concepção deste protótipo, e também os resultados de comparações feitas entre as medições da Estação Mesomóvel e de uma estação da rede operacional de observação em superfície. A operação da Estação Mesomóvel em modo de interceptação de tempestades é discutida em termos das estratégias de análise e previsão de tempo empregadas, da logística de deslocamento, e dos dados atmosféricos obtidos em campo. Resultados da análise dos dados coletados pela Estação Mesomóvel mostraram sua capacidade de amostrar a evolução, em alta frequência, de fenômenos convectivos da escala meso-g, como frentes de rajada, piscinas de ar frio, mesoaltas e altas taxas de precipitação, que tipicamente é mal representada pela rede de observação de superfície em escala sinótica. Esta pesquisa demonstrou que é factível realizar no Brasil a coleta de dados meteorológicos com qualidade científica através da estratégia de interceptação de tempestades convectivas.

O ‘Parsley Massacre’ – o assassinato de haitianos que viviam na República Dominicana em 1937 – é o tema de The farming of bones (1998), escrito por Edwidge Danticat, que oferece ao leitor o testemunho ficcional de uma sobrevivente da violência do genocídio. De forma similar, em Solar storms (1995), Linda Hogan faz a descendente de um povo que foi massacrado a protagonista de uma busca pelo passado e pela história de seu povo. Ambos os romances empregam estratégias narrativas em busca da representação ficcional do trauma como experiência pessoal e coletiva, implicando o leitor na produção de sentido (CARUTH 1996; FREUD; 1920). É através do recordar e reviver o passado que os sujeitos traumatizados podem tentar compreender sua situação presente e reivindicar uma identidade para si mesmos (HALL, 2006). A revisão do passado, e precisamente de um passado silenciado, proporciona que as vozes de uma comunidade possam ser ouvidas e suas histórias trazidas à luz. Nesse estudo, eu busco investigar de que forma tais histórias são construídas, quais seus efeitos na superfície textual e suas implicações no empoderamento dos sujeitos. Além disso, investigo as conexões entre o corpo traumatizado e a mente, compreendendo o corpo como uma superfície histórica que recebe a inscrição da experiência humana (GROSZ, 1994). / The Parsley Massacre – the killing of Haitians living in the Dominican Republic in 1937 – is the theme of The farming of bones (1998), written by Edwidge Danticat, who offers the reader a fictional testimony of a survivor of the violence of genocide. Similarly, in Solar storms (1995), Linda Hogan makes the descendant of a massacred people the protagonist of a search for the past and her people’s history. Both novels employ narrative strategies for a fictional representation of trauma, as personal and collective experiences, implicating the reader in the production of meaning (CARUTH 1996; FREUD; 1920). It is by reliving and re-experiencing the past that traumatized subjects can make sense of their present condition and claim an identity for themselves (HALL, 2006). It is by revising the past, a historically silenced past, that the voices of a community can be heard and their stories brought out to light. In this study, I am also interested in how these stories are constructed, in what are their effects on the surface of the text and their implications in the empowering of subjects. Moreover, I investigate the connections between the traumatized body and the mind, understanding the body as an historical surface for the inscription of human experience (GROSZ, 1994).

O ‘Parsley Massacre’ – o assassinato de haitianos que viviam na República Dominicana em 1937 – é o tema de The farming of bones (1998), escrito por Edwidge Danticat, que oferece ao leitor o testemunho ficcional de uma sobrevivente da violência do genocídio. De forma similar, em Solar storms (1995), Linda Hogan faz a descendente de um povo que foi massacrado a protagonista de uma busca pelo passado e pela história de seu povo. Ambos os romances empregam estratégias narrativas em busca da representação ficcional do trauma como experiência pessoal e coletiva, implicando o leitor na produção de sentido (CARUTH 1996; FREUD; 1920). É através do recordar e reviver o passado que os sujeitos traumatizados podem tentar compreender sua situação presente e reivindicar uma identidade para si mesmos (HALL, 2006). A revisão do passado, e precisamente de um passado silenciado, proporciona que as vozes de uma comunidade possam ser ouvidas e suas histórias trazidas à luz. Nesse estudo, eu busco investigar de que forma tais histórias são construídas, quais seus efeitos na superfície textual e suas implicações no empoderamento dos sujeitos. Além disso, investigo as conexões entre o corpo traumatizado e a mente, compreendendo o corpo como uma superfície histórica que recebe a inscrição da experiência humana (GROSZ, 1994). / The Parsley Massacre – the killing of Haitians living in the Dominican Republic in 1937 – is the theme of The farming of bones (1998), written by Edwidge Danticat, who offers the reader a fictional testimony of a survivor of the violence of genocide. Similarly, in Solar storms (1995), Linda Hogan makes the descendant of a massacred people the protagonist of a search for the past and her people’s history. Both novels employ narrative strategies for a fictional representation of trauma, as personal and collective experiences, implicating the reader in the production of meaning (CARUTH 1996; FREUD; 1920). It is by reliving and re-experiencing the past that traumatized subjects can make sense of their present condition and claim an identity for themselves (HALL, 2006). It is by revising the past, a historically silenced past, that the voices of a community can be heard and their stories brought out to light. In this study, I am also interested in how these stories are constructed, in what are their effects on the surface of the text and their implications in the empowering of subjects. Moreover, I investigate the connections between the traumatized body and the mind, understanding the body as an historical surface for the inscription of human experience (GROSZ, 1994).

This study investigates the temporal, spatial and impact characteristics of severe convective storm hazard and risk in the Eastern Cape Province of South Africa. Using historical data on severe convective storms dating from 1897, patterns of the hazard threat and risk to various geographic populations were investigated. A conceptual framework that emphasises the combined role hazard and vulnerability play in defining risk was used for the study. A methodology for ranking the severity of the storms in the historical dataset, based on recorded damage/impact, was specifically developed for the study. It is intended that this methodology will have a potentially wider application and may be adapted to a range of hazard impact and risk studies in South Africa and internationally. The study was undertaken within the context of the South African Disaster Management Act of 2002. Findings of the study show that severe convective storms can occur throughout the province, but there are clearly demarcated areas of higher frequency and concentration. The impact of storms is particularly severe on impoverished and vulnerable rural populations in the eastern parts of the province, where there is an urgent need for building capacity in disaster risk management. A major outcome of the study is the production of a severe convective storm hazard/risk map of the Eastern Cape, which it is hoped will be of benefit to a number of stakeholders in the province, particularly disaster management, but also the South African Weather Service, agricultural organisations, development/planning authorities, educational authorities and risk insurers. It is hoped that this map and the study in general will assist in guiding the operational responses of the various authorities, especially in terms of those interventions aimed at disaster risk reduction in the Eastern Cape.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A climatological and synoptic evaluation of the atmospheric environments prone to severe weather under N-NW low-level flow over Rio Grande do Sul (RS) State is conducted. Atmospheric profiles from 00Z, 06Z, 12Z and 18Z were calculated using Reanalysis data for two geographically distinct regions of the state: the Serra Gaúcha (SG) and the Campanha Gaúcha (CG). Several convective parameters were calculated to identify the atmospheric ingredients useful to severe storm forecasting, which are: conditional instability, moisture availability and Vertical Wind Shear (VWS). To verify the occurrence of convective storms during, or up to 6 hours the low-level N-NW flow events, cold cloud tops were identified using images from GOES 10 and 12 satellites, associating each event with a brightness temperature category. The seasonal, annual and the distribution of the parameters as a function of depth of the convective activity is based on a quantile analysis. The parameter space between conditional instability and VWS is also investigated. The synoptic environments in which the storms develop across RS were analyzed by using mean and anomaly mean composite patterns of the relevant meteorological fields for convective weather forecasting. The climatology showed that the differences between the large-scale environments favorable to the development of storms in SG and CG are small. The expected seasonal behavior of conditional instability and VWS was well represented in this climatology. The transitional seasons are those which present both conditions of high instability and VWS and also record more storms in this regime. The analysis of the mean composites fields highlights the lack of pronounced Lapse Rates in pre-convective environments in RS. The pressure fall induced by a mid-level trough accelerates the N-NW flow which assumes a low-level jet character, responsible for increasing the supply of heat, moisture and low-level VWS. The deeper storms stand out from the others because they develop in environments with enhaced moisture and conditional instability anomalies. / Uma avaliação climatológica e sinótica dos ambientes atmosféricos conducentes à ocorrência de tempestades severas em situações de vento de N-NO em baixos níveis sobre o Rio Grande do Sul (RS) é realizada neste trabalho. Perfis atmosféricos das 00Z, 06Z, 12Z e 18Z foram calculados utilizando-se dados de Reanálise para duas regiões geograficamente distintas do estado: a Serra Gaúcha (SG) e a Campanha Gaúcha (CG). Foram calculados diversos parâmetros convectivos utilizados na identificação dos ingredientes atmosféricos necessários para o desenvolvimento de tempestades severas, que são: instabilidade condicional, oferta de umidade e cisalhamento vertical do vento (CVV). Para verificar a ocorrência de nebulosidade convectiva durante, ou até 6 horas após os eventos de escoamento de N-NO em baixos níveis, topos frios de nuvem foram identificados utilizando-se imagens dos satélites GOES 10 e 12, associando cada evento a uma classe de temperatura de brilho. A climatologia sazonal, anual e a distribuição dos parâmetros como função da profundidade da atividade convectiva é feita com base em uma análise de quantis. O espaço de parâmetros entre instabilidade condicional e CVV é também investigado. Os ambientes sinóticos em que as tempestades se desenvolvem no RS foram analisadas através de composições e anomalias médias dos campos meteorológicos relevantes para a previsão convectiva. A climatologia mostrou que as diferenças entre os ambientes em grande escala favoráveis ao desenvolvimento de tempestades na SG e CG são pequenas. O comportamento sazonal esperado da instabilidade condicional e do CVV foi bem representado nesta climatologia. A estações de transição são aquelas que apresentam simultaneamente as condições de alta instabilidade e CVV e também registram mais tempestades neste regime. A análise das composições médias ressalta a ausência de Lapse Rates acentuados nos ambientes pré-convectivos no RS. A queda de pressão induzida por um cavado em níveis médios acelera o escoamento de N-NO que assume a forma de um jato de baixos níveis, responsável por aumentar a oferta de calor, umidade e CVV em baixos níveis. As tempestades mais profundas destacam-se das demais por se desenvolverem em ambientes com acentuada anomalia de umidade e instabilidade condicional.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / An investigation of the atmospheric environments prone to severe convective weather is conducted for the subtropics of South America, east of the Andes Mountain Range. Upper air soundings valid at 00Z and 12Z for six sounding sites in subtropical South America (namely, Porto Alegre/BRA, Florianópolis/BRA, Curitiba/BRA, Foz do Iguaçu/BRA, Resistência/ARG e Buenos Aires/ARG) are employed to generate a short 12-yr climatology (from January 1998 to December 2009) of some of the main necessary ingredients for severe thunderstorm development: moisture availability, conditional instability, and vertical wind shear (VWS). The goal of the climatology is to document the typical magnitudes and seasonal variability of those ingredients with the aid of convective parameters. Threshold magnitudes for such parameters were objectively determined (via quantile analysis) and tested as cut-off criteria utilized to discriminate the severe weather environments. To that end, classic North-American threshold values extracted from the literature were also tested and the results compared vis-à-vis the South-American counterparts. Distinct combinations of such thresholds were employed to select atmospheric profiles theoretically conducive to severe thunderstorms and tornadoes. Atmospheric profiles obtained from the NCEP-NCAR Reanalysis data valid at 18Z were also used. The time and space distribution of the selected severe weather profiles were examined, emphasizing the seasonal variation and geographic distribution. From these sampled profiles, composite analysis were built for and Principal Component Analysis were applied to relevant meteorological variables at distinct vertical levels in order to search for the associated synoptic-scale patterns. The climatology succesfully reproduced the expected seasonal behavior of parameters that are indicative of conditional instability and VWS. Compared to the North-American climatology, the magnitudes found for the 700-500hPa lapse rates, 0-6km bulk shear and height of the LCL were lower in South America. The seasonal variability and space distribution of the severe weather profiles suggest that there exists an equatorward [poleward] displacement of the severe weather activity as winter [summer] approaches. The synoptic pattterns associated with the severe weather environments is different from those traditionally recognized for North America, particularly at the surface. / Neste trabalho é realizada uma investigação dos ambientes favoráveis ao desenvolvimento de convecção severa nos subtrópicos da América do Sul (AS) à leste dos Andes. Sondagens de ar superior das 00Z e 12Z de seis estações distribuídas na região subtropical da AS (quais sejam: Porto Alegre/BRA, Florianópolis/BRA, Curitiba/BRA, Foz do Iguaçu/BRA, Resistência/ARG e Buenos Aires/ARG), foram utilizadas para gerar uma pequena climatologia (12 anos; de janeiro de 1998 a dezembro de 2009) de alguns dos principais ingredientes necessários para o desenvolvimento de convecção severa: oferta de umidade, instabilidade condicional termodinâmica e cisalhamento vertical do vento (CVV). A climatologia visou documentar as magnitudes típicas e a variação sazonal destes parâmetros para a região de interesse. Valores significativos dos parâmetros foram objetivamente identificados via análise de quantis e testados como limiares combinados para salientar ambientes favoráveis ao desenvolvimento de tempestades severas. Limiares para a América do Norte documentados na literatura também foram testados para este fim e confrontados com os respectivos valores da amostragem sul-americana. Diferentes combinações destes limiares foram empregadas para se extrair os perfis atmosféricos considerados teoricamente favoráveis a tempestades severas e tornados. Perfis de tempo severo também foram extraídos dos dados da Reanálise do NCEP-NCAR válidos às 18Z. Foi examinada a distribuição temporal e espacial destes ambientes de tempo severo explorando sua sazonalidade e distribuição geográfica. Partindo destes perfis, foram analisados os padrões sinóticos predominantes na região através da composição média e Análise de Componentes Principais para as variáveis meteorológicas mais relevantes em diferentes níveis verticais. A climatologia reproduziu bem o comportamento sazonal esperado dos parâmetros de instabilidade termodinâmica e CVV. Em comparação com a climatologia da América do Norte encontrou-se para a América do Sul valores mais baixos de lapse rates na média troposfera, CVV na camada entre 0-6km, e altura do NCL. A distribuição sazonal e espacial dos perfis de tempo severo sugere uma migração geográfica das condições de tempo severo das latitudes mais baixas [altas] para as latitudes mais altas [baixas] à medida que nos aproximamos dos meses de verão [inverno]. O padrão sinótico de tempo severo na América do Sul é diferente daquele tradicionalmente documentado para a América do Norte, especialmente em superfície.