As the decline in Arctic sea ice extent makes this region more accessible, the need is increasing for effective seasonal sea ice forecasting to facilitate operational planning. Recently, coupled global climate models (CGCMs) have been used to address the need for effective sea ice forecasting on seasonal time scales. This thesis assesses the operational utility of the Canadian Seasonal to Interannual Prediction System (CanSIPS) for seasonal sea ice forecasting. This assessment consists of two separate studies. The first uses hindcasting to analyze the skill of two versions of CanSIPS, as well as an intermediate version, on the pan-Arctic as well as regional scales. This approach allows for an overall assessment of the system's skill in addition to providing insight with regards to the features in each version which improved that skill. This study finds that the use of a new initialization procedure for sea ice concentration and thickness improved forecast skill on the pan-Arctic scale as well as in the Central Arctic, Barents Sea, Laptev Sea, and Sea of Okhotsk. This study also shows that the substitution of one of the constituent models in the system improved forecast skill on the pan-Arctic scale as well as in the GIN, Barents, Kara, East Siberian, Chukchi, Bering, and Beaufort Seas. Overall, the new version of CanSIPS was found to be generally more skillful than previous versions. The second study conducts a potential predictability experiment on CanCM4, the constituent CGCM common to all versions of CanSIPS considered in this study. This study follows the methodology introduced by \cite{Bushuk2018} which allows for a more complete assessment of the dependency of potential predictability on initialization month than previous studies and for comparisons to be made between potential predictability and operational skill. This analysis is again done on both the pan-Arctic and regional scale. The findings of this experiment show that CanCM4 has relatively low potential predictability relative to other models and explains results previously presented in a multi-model study by \cite{Day2016}. Further, the characteristics of CanCM4's potential predictability share similarities with other models including greater predictability at longer lead times for winter target months than summer target months, greater predictability in the Atlantic sector than the Pacific sector, and the presence of the spring predictability barrier on the pan-Arctic scale as well as in several regions. The comparison of operational skill to potential predictability provides a general overview of the ``skill gap" which may be closed with improvements in initialization procedures and model physics. This comparison does, however, come with some caveats due to differences in the statistical characteristics of the perfect model and the climate system it represents. Together, the operational skill assessment of different versions of CanSIPS and the potential predictability experiment conducted on one of its constituent models, CanCM4, demonstrate that while room for improvement exists, the recent development of this forecast system has clearly increased its operational utility as a seasonal sea ice forecasting tool. / Graduate

Made available in DSpace on 2016-12-23T14:34:11Z (GMT). No. of bitstreams: 1 renatabomfim.pdf: 583145 bytes, checksum: 85156f032a2bfc6e29911dc483ff91f7 (MD5) Previous issue date: 2009-09-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Propõe reflexões acerca das vozes sociais e arquetípicas presentes nos livros de soneto Livro de Mágoas (1919), Livro de Sóror Saudade (1921), Charneca em Flor (1930) e Reliquiae (1931), da poeta portuguesa Florbela Espanca. Para tal utilizam-se como arcabouços teóricos básicos, as obras de Mikhail Bakhtin, especialmente os conceitos de dialogismo e polifonia, e de Carl Gustav Jung, os conceitos de arquétipos e inconsciente coletivo. A poética de Florbela Espanca é polifônica por abarcar uma multiplicidade de vozes sociais e seus respectivos discursos, ela é também arquetípica, pois reproduz experiências que extrapolam o âmbito pessoal, encontrando ressonância no coletivo de diferentes épocas. Dentre estas vozes arquetípicas femininas expressas na sua poesia, analisa-se as de Lilith, Eva e Maria, por abarcarem aspectos como a sensualidade, o erotismo, a aspiração sacerdotal e virginal, a dor, a angústia, o desejo, o sonho e a vaidade, temas que refletem certos desejos de fazer dialogar dicotomias, termos opostos que, em uma sociedade patriarcal não conseguem alcançar expressão plena. A dificuldade de realização profissional e pessoal da mulher numa sociedade tradicional e falocrata como a do primeiro quartel do século XX, no caso de Florbela é, possivelmente, a geradora de uma angústia tal na poeta que levou-a ao suicídio, destino interpretado como tragédia moderna aos moldes raymondianos. A dificuldade de enquadramento do feminino na ordem patriarcal do mundo, é poeticamente trabalhada por Florbela que responde com um texto marcado pela inquietação, pela busca e pela arrância, e encontra na utopia de Fredric Jameson, um caminho de expressão, a partir da denúncia do paradigma exaurido da dualidade, demonstrado pelo desejo de infinito e de integração com a natureza. A crítica literária Maria Lúcia Dal Farra é o aporte fundamental no que diz respeito à obra e a vida de Florbela Espanca, e outros autores auxiliarão na construção dessa pesquisa mosaico que objetiva ser interdisciplinar. / This research proposes some reflections regarding de social voices and perfect models present in the sonnet books Livro de Mágoas (1919), Livro de Sóror Saudade (1921), Charneca em Flor (1930) e Reliquiae (1931), from the Portuguese poetess Florbela Espanca. Therefore we will use as basic theoretical mark, the works of Mikhail Bakthin, specially the concepts of dialogism and polyphony, and of Carl Gustav Jung, the concepts of perfect models and collective unconscious. The poetic of Florbela Espanca is polyphony because it embraces a multiplicity of social voices and its respective speeches, she is also a perfect model, because she reproduces experiences that go beyond the personal ambit, finding resonance in t e collective of different times. Among those perfect models feminine voices expressed into her poetry, we will analyze those of Lilith, Eva and Mary. This representations embrace aspects such as the sensuality, the eroticism, the clerical and virginal aspirations, the pain, the anxiety, the desire and the vanity, themes that reflect certain desires of making dialectics dialog, we have opposites that, in a father based society can t reach the complete expression. The hardship of professional and personal realization of a woman in a traditional society like the one in the first quarter of the 20th century, in that case Florbela, was generated from a anxiety in the poetess that drove her to suicide, fate that we interpreter as modern tragedy , in the raymondian framework. The difficulties found by woman in a patriarchal world, is poetically worked by Florbela that respond with a text marked by the uneasiness, by the search and by wish of finding, in the utopia of Frederic Jameson, a way of expression from the plea of the paradigm that come from duality, demonstrated by the desire of infinity and integration with nature. The literate critic, Maria Lúcia Dal Farra, will be the base fundament in what approaches the life and work of Florbela Espanca, and other authors will help in the construction of this mosaic research that, has as a goal to be interdisciplinary.

The thermally-driven rotating annulus is a laboratory experiment used to study the dynamics of planetary atmospheres under controlled and reproducible conditions. The predictability of this experiment is studied by applying the same principles used to predict the atmosphere. A forecasting system for the annulus is built using the analysis correction method for data assimilation and the breeding method for ensemble generation. The results show that a range of flow regimes with varying complexity can be accurately assimilated, predicted, and studied in this experiment. This framework is also intended to demonstrate a proof-of-concept: that the annulus could be used as a testbed for meteorological techniques under laboratory conditions. First, a regime diagram is created using numerical simulations in order to select points in parameter space to forecast, and a new chaotic flow regime is discovered within it. The two components of the framework are then used as standalone algorithms to measure predictability in the perfect model scenario and to demonstrate data assimilation. With a perfect model, regular flow regimes are found to be predictable until the end of the forecasts, and chaotic regimes are predictable over hundreds of seconds. There is a difference in the way predictability is lost between low-order chaotic regimes and high-order chaos. Analysis correction is shown to be accurate in both regular and chaotic regimes, with residual velocity errors about 3-8 times the observational error. Specific assimilation scenarios studied include information propagation from data-rich to data-poor areas, assimilation of vortex shedding observations, and assimilation over regime and rotation rate transitions. The full framework is used to predict regular and chaotic flow, verifying the forecasts against laboratory data. The steady wave forecasts perform well, and are predictable until the end of the available data. The amplitude and structural vacillation forecasts lose quality and skill by a combination of wave drift and wavenumber transition. Amplitude vacillation is predictable up to several hundred seconds ahead, and structural vacillation is predictable for a few hundred seconds.