Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 12).

Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (leaves 177-204). Also available via the World Wide Web.

The transport of low-salinity waters through the Canadian Arctic Archipelago links the North Pacific, Arctic, and North Atlantic Oceans. This transport is influenced by many related small-scale processes including mixing, internal hydraulics, and internal tide generation. In this thesis, I quantify and elucidate the physics of such processes with aims of addressing discrepancies between observed and simulated fluxes through the Archipelago and advancing the skill of numerical models by identifying shortcomings and informing where and how progress can be achieved. To address the dearth of mixing rates across the network of channels, I first use a large-scale model to obtain baseline estimates of the spatial and seasonal variability of the vertical buoyancy flux. Much of the mixing occurs in the eastern half of the Archipelago and is attributed to the abundance of sills and narrow channels. Indeed, the so-called 'central sills area' is shown to be a mixing hot spot. I investigate this region further using high-spatial-resolution observational transects to examine the role of tides, which are excluded from the large-scale model. The many shallow channels here accelerate tidal currents and thereby induce strong bottom boundary layer dissipation. This is the largest energy sink within an observationally constrained energy budget. The generation of internal tides is another primary sink of barotropic tidal energy. Because the study site lies poleward of the critical latitudes of the dominant tidal constituents, internal tides propagate as internal Kelvin waves. Idealized, process-oriented modelling demonstrates that the amplitudes of such waves, or similarly the energy extracted from the barotropic tide, is sensitive to channel width because waves generated at each side of the channel interfere. Given the multiple connecting channels of the Archipelago, it is difficult to make a priori estimates of internal tide generation for a given channel. Nevertheless, the phenomenology I describe will be detectable in, and a requisite to understanding, pan-Arctic or global three-dimensional tidal models, which are becoming more prevalent. / Graduate

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-08-13T16:48:52Z No. of bitstreams: 1 THAÍS REGINA BENEVIDES TRIGUEIRO ARANHA – DISSERTAÇÃO (PPGMET) 2016.pdf: 1566781 bytes, checksum: 416f76ec2bd82ddca22b8e30392097f9 (MD5) / Made available in DSpace on 2018-08-13T16:48:52Z (GMT). No. of bitstreams: 1 THAÍS REGINA BENEVIDES TRIGUEIRO ARANHA – DISSERTAÇÃO (PPGMET) 2016.pdf: 1566781 bytes, checksum: 416f76ec2bd82ddca22b8e30392097f9 (MD5) Previous issue date: 2016-03-04 / CNPq / Neste estudo utilizou-se o esquema TEB - Town Energy Budget acoplado ao modelo numérico BRAMS - Brazilian Developments on the Regional Atmospheric Modeling System para analisar as variáveis atmosféricas influenciadas pela urbanização da cidade de Campina Grande - PB no período seco. Esta região, no que diz respeito ao contexto econômico-político, embora seja compreendida como uma cidade média apresenta indicadores semelhantes aos que caracterizam as metrópoles. Foram realizados dois experimentos, um com o TEB ativado para a representação das superfícies urbanizadas e outro com o TEB desativado, denominado de STEB, em que desconsidera a dinâmica urbana, para atestar a influência da cidade nas variáveis meteorológicas. Os resultados mostraram que a cidade de Campina Grande é grande o suficiente para influenciar o próprio microclima. A urbanização aumenta a temperatura durante a tarde e início da noite. O albedo da superfície é fortemente influenciado pela dinâmica da cidade, com impacto no saldo de radiação. O fluxo de calor sensível aumenta e o de calor latente diminui devido ao efeito da cidade. Observa-se algum impacto na temperatura, umidade e fluxos nos arredores da cidade. / In this study we used the TEB scheme - Town Energy Budget coupled to the numerical model BRAMS - Brazilian Developments on the Regional Atmospheric Modeling System to analyze atmospheric variables influenced by the urbanization of the city of Campina Grande - PB in the dry season. This city presents indicators similar to those that characterize the metropolis in economic and political context, although it is considered as an average city. Two experiments were conducted, one with the TEB activated for the representation of urban surfaces and other with the TEB disabled, namely STEB, which disregards the urban dynamics, in order to attest to the influence of the city in weather variables. The results showed the city of Campina Grande is large enough to influence its own microclimate. Urbanization increases the temperature during the afternoon and early evening. The surface albedo is strongly influenced by the dynamics of the city, with impact on the radiation balance. The sensible heat flux increases and the latent heat decreases due to the effect of the city. We also observed an impact on temperature, humidity and flows around the city.

In ecological risk assessment, mechanistic effect models (MEMs) are thought to overcome the limitation of standard laboratory single species test by accurately extrapolating the models to population-level. This review introduces the basic theory of MEMs-dynamic energy budget theory which can connect with toxicokinetic/ toxicodynamic models to describe the interaction of toxicants and organisms. This review summarizes some typical MEMs which simulate different scenarios, pesticides and species, and compared their modelling performance according to the guidance on good effect models of European Food Safety Authority, in order to judge if it is accounting for all modelling steps. In addition, a summary of the linkage of MEMs in pesticides ecological risk assessment have been discussed, especially evaluating the linkage results of ‘MODELINK’ workshop. However, there is no genuine application of MEMs in pesticides ecological risk assessment in real world today, because there is no validated model built with acceptable predictive power to motivate the ecological assessors or shareholders to use effect models confidently. Therefore, there is still a long way to develop an effect model which is valid enough and has strong prediction power.

A population of the red-eared slider, Pseudemys scripta, in north central Texas was studied from 1975 to 1980. A life history energy budget was developed for a typical individual in the population and the population dynamics were estimated. A growth model relating growth rate to mean plastron length (PL) was developed from recapture data and used to 1) establish age classes and 2) age individuals. Growth rate was highly variable in both sexes. Females grew more rapidly than males and attained a larger maximum size (230 mm and 195 mm PL in females and males respectively). Females reached sexual maturity in their ninth year at a PL of 185-190 mm. Males matured in their sixth year at a PL of 90-100 mm. Females produced three clutches annually; clutch size ranged from 7 to 14 (X=10.3; N=20). Ova were enlarged in the early spring and ovulation began in late April and early May. Egg laying occurred from mid- May through June. Both egg size and clutch size increased with female body size. Lipid levels were variable within and among seasons. No annual lipid cycling pattern was evident in females. The proportion of assimilated energy devoted to reproduction, a measure of reproductive effort (RE), by females, was 13 per cent the first year of maturity (9 y) and increased to 20 per cent by their twentieth year. Lifetime RE was 16 per cent. Population density was estimated as 51 males and 50 females per ha in a 8.2-ha area of the lake. Young juveniles (less than 2 y) were not present although other subadult age classes were about equally represented. Fewer adults were encountered. An annual total production of 4000 eggs was estimated for the population present in 1977. A survival rate of from 2 to 18 per cent was estimated for the period between egg laying to 3 y. The large group of turtles younger than 10 y represented an expanding (Rₒ=1.8) lake population and the small group of older turtles were the remnants of a creek population present before Moss Lake was formed. The demographic environment, high juvenile mortality and low adult mortality, was suggested as a primary selective force shaping the life history characteristics of the Moss Lake scripta population.

Les modifications environnementales qui affectent aujourd'hui les milieux marins recouvrent des problématiques scientifiques et sociétales majeures, d'autant que ces changements devraient s'accélérer au cours du 21ème siècle. Comprendre et anticiper la réponse de la biodiversité marine à ces changements représente un enjeu scientifique d'actualité. Les approches biogéographiques et macroécologiques constituent un cadre scientifique dans lequel il est possible d'étudier, de décrire, et de comprendre les motifs de distribution des espèces à large échelle et d'estimer leur évolution possible face aux changements environnementaux. C'est notamment le cas dans l'océan Austral où les effets du changement climatique se font déjà sentir et où les modifications environnementales associées pourraient avoir des effets profonds sur la structure et le fonctionnement des écosystèmes. Malgré de récents efforts d'échantillonnage, nos connaissances sur la distribution des espèces dans l’océan Austral comptent encore de nombreuses lacunes attribuables au caractère récent des découvertes, à l'isolement et à l'éloignement de cet océan d'accès difficiles. Dans ce contexte, les objectifs de cette thèse consistaient à mieux comprendre les motifs de distribution d'espèces à l’échelle de l’océan Austral, à mettre en évidence les facteurs qui en sont à l’origine et enfin, à évaluer l’impact du changement climatique sur leur distribution. Pour cela,différents types de modèles de niche écologique (MNE) ont été employés. Les échinides (oursins), organismes communs des communautés benthiques de l’océan Austral ont servi de modèle d'étude pour ce travail. Afin de générer des MNE, notamment de type corrélatif, une base de données d’occurrence des espèces d'échinide a été actualisée. L’effort d’échantillonnage a ainsi pu être cartographié et quantifié pour l'ensemble de l'océan Austral ;il s'est révélé très hétérogène, principalement concentré aux abords des zones peu profondes et des bases scientifiques. Cela peut générer des biais dans la qualité et la performance prédictive des MNE ainsi que dans les projections spatiales associées. La robustesse des MNE corrélatifs a donc été testée au regard de l’effort d’échantillonnage mais aussi en tenant compte de la taille des niches écologiques des espèces étudiées ainsi que des contraintes biogéographiques existantes. Cette approche a permis de souligner l’importance de certains facteurs abiotiques pour expliquer la distribution des espèces à large échelle. Il apparaît aussi qu’une meilleure qualité d'échantillonnage génère des MNE plusrobustes mais que les résultats sont fortement dépendants de la taille des niches écologiques et de la présence de barrières biogéographiques.Ces MNE individuels réalisés pour de nombreuses espèces ont été combinés entre eux et ont permis de définir dix écorégions à l'échelle de l'océan Austral qui se distinguent par leur composition faunique et leurs caractéristiques environnementales. Les résultats montrent une forte individualisation des faunes antarctiques par rapport aux régions subantarctiques ainsi que l'existence de liens fauniques entre l’Amérique du Sud et les îles subantarctiques d'une part, ainsi qu’entre la nouvelle Zélande et la mer de Ross de l'autre. Ils soulignent également l’importance de facteurs environnementaux comme la température de fond, la profondeur et la géomorphologie pour expliquer les motifs de distribution des espèces. Enfin, des modèles prédictifs futurs ont été produits sur la base du scénario RCP 8.5 du GIEC. Ils montrent que les régions subantarctiques pourraient être particulièrement impactées par les changements environnementaux y compris au sein du réseau d’Aires Marines Protégées (AMP) mis en place dans l’océan Austral. Les MNE corrélatifs ont fait l’objet de critiques récurrentes dans la littérature scientifique du fait de leur incapacité à prendre en compte les dynamiques biologiques liant espèce et environnement, et de leurs limites pour l'extrapolation des données et la production de projections futures. Des MNE de types mécanistiques reposant sur l'approche des Dynamic Energy Budget ont donc été produits pour l'espèce Sterechinus neumayeri (Meissner, 1900) grâce aux nombreuses connaissances acquises sur le développement et la croissance de l'espèce. La comparaison entre MNE corrélatifs et mécanistiques a permis d’apprécier leur complémentarité et de proposer des projections robustes pour la période actuelle. En revanche, les projections futures ont montré de fortes divergences entre modèles, soulignant la nécessité d'utiliser plusieurs approches de modélisation pour mieux comprendre la distribution des espèces à large échelle et évaluer l’impact du changement climatique sur la biodiversité marine de l’océan Austral. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

The purpose of this study is to investigate variation in water export and instream temperatures throughout the open water season in a beaded Arctic stream, consisting of small pools connected by shallow chutes. The goals are to better understand heat and mass movement through these systems, how this may impact chemical and biological processes, and the resulting shifts with changes in climate. This is accomplished by first examining the extent and variability of water storage and export through qualitative analysis of observational data. Further, heat fate and transport is examined through development of an instream temperature model. The model formulation, a simple approach to model calibration and validation, and information regarding residence and characteristic times of different pool layers are presented. Using temperatures measured at high spatial resolution within the pools and surrounding bed sediments as well as other supporting data (e.g., instream flow, specific conductivity, weather data, and bathymetry), various types of storage within the pools, banks, and marshy areas within the riparian zone, including subsurface flow paths that connect the pools, were found. Additionally, data illustrated that some pools will stay stratified during higher flow periods under certain weather conditions. Through modeling efforts, the dominant heat sources were found to vary between stratified layers. It was also found that potential increases in thaw depths surrounding these pools can shift stratification and mixing patterns. These shifts can further influence mass export dynamics and instream water quality. Given the amount and different types of storage within these systems and the influence of stratification patterns on the residence times in the pools, Imnavait Basin and similar beaded Arctic watersheds will likely experience delayed export of nutrients that are limiting in most Arctic systems.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics; and, (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1967. / Includes bibliographical references (leaves 167-170). / A monthly statistical analysis was made of the effects of large scale horizontal eddy transport processes on the zonal momentum, heat and energy budgets for three layers of the 1965 stratosphere. Geostrophic wind components were computed from IQSY data at 100, 50, 30 and 10 mb for use in calculating the statistical quantities -used in the analysis. It was found that temporal and spatial variances and covariances -computed from monthly means of temperature and geostrophic wind components give meaningful results when used in the computation of momentum, heat and energy balances. Monthly meridional distributions of eddy transports and energy conversions show large latitudinal and height variations. They also indicate a physically reasonable compatibility with month to month changes in zonal mean values of temperature, zonal wind and geo-potential. It was further determined that in the winter, the eddies in the middle stratosphere convert a self contained source of zonal available potential energy into eddy available potential energy. It is speculated that further conversion of this energy eventuates in its availability as a significant source for the mean zonal motions. / by Merwin Eugene Richards. / M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1979. / Microfiche copy available in Archives and Science. / Bibliography: leaves 86-88. / by Dawna Lisa Paton. / M.S.