The stratosphere of Saturn is highly variable. With an axial tilt of 26.7°, Saturn experiences seasons like Earth and is currently approaching northern summer solstice in 2017. In addition to general seasonal change, previous studies have highlighted that Saturn's stratosphere is host to a range of dynamical phenomena. These processes have an observable effect on the vertical temperature profile and stratospheric concentrations of acetylene (C₂H₂) and ethane (C₂H₆), which may be determined or retrieved from thermal infrared observations of Saturn. This thesis presents an analysis of observations of Saturn acquired by Voyager's IRIS (Infrared Interferometer Spectrometer, 180 - 2500 ^cm-1, Hanel et al.,[1980]) instrument in 1980, Cassini's CIRS (Composite Infrared Spectrometer, 10 - 1400 ^cm-1, Flasar et al.,[2004]) instrument from 2005 to 2012 and the Celeste spectrometer (400 - 2000 ^cm-1, Moran et al.,[2007]) on NASA's IRTF (Infrared Telescope Facility) in 2012 in order to track seasonal and interannual changes in Saturn's stratosphere. The concentrations of C₂H₂ and C₂H₆ were seen to decrease at 15°S and increase at 25°N from 2005 to 2009/2010. These changes at 15°S and 25°N respectively indicate upward and downward branches associated with cross-equatorial seasonally-reversing Hadley circulation that has been predicted by a general circulation model [Friedson and Moses, 2012]. Strong cooling of up to 17 K at high-southern latitudes from 2005 to 2010 suggests an autumnal weakening of a vortex that appears to form at the pole of the summer hemisphere [Fletcher et al., 2008]. The emergence of a similar northern polar vortex as northern summer solstice approaches was yet to be observed in 2012. Interannual differences in the equatorial temperature structure between 1980 and 2009/2010 suggest Saturn's semiannual oscillation (or SSAO, Fouchet et al. [2008]; Orton et al. [2008]) has been captured in a different phase from one year to the next. This is puzzling since the oscillation would be expected to have undergone two cycles assuming its period is half a Saturn year (14.7 years). This contrast is suggestive that the period of the SSAO is more quasisemiannual.

No description available.

Mesoscale turbulence is ubiquitous in the surface ocean and has significant impact on the large-scale ocean circulation and its interaction with the climate. Ocean currents are most energetic in the mesoscale range on the scales of 20-200 km and recent studies have shown that the surface kinetic energy associated with the mesoscale undergo a large seasonal modulation. At scales below the mesoscale where geostrophic approximation breaks down lies the submesoscale (1-20 km). It is at this scale that baroclinic instabilities feed off the available potential energy stored in the deep wintertime mixed layers, known as mixed-layer instability, and in return energize the mesoscale via inverse energy cascade under the constraint of stratification and rotation. Mixed-layer instability (MLI) is inherently submesoscale due to the depth scale associated with it. We show the robustness of MLI on global scale in modulating seasonality in surface mesoscale turbulence by analyzing outputs from a Community Earth System Model fully ocean-atmosphere coupled run with eddying resolution. Due to the rigorous vertical velocities associated with mesoscale turbulence, in the context of climate, they have been shown to make major contributions to the transport of heat and tracers including carbon. More recently, it has been argued that submesoscale heat transport may dominate over the mesoscale. We ask the same question for tracers: What is the relative contribution of submesoscale transport (local effect) over the energized mesoscale via inverse energy cascade (remote effect)? In order to investigate their impact on the dynamics and tracer transport, we run our own seasonally resolving submesoscale permitting channel model configured to represent the zonal-mean view of the Southern Ocean coupled to a full biogeochemical model. The Southern Ocean is unique in that, apart from it being the only zonally re-entrant basin on Earth, it is one of the high-nutrient low-Chlorophyll oceans and iron is predominantly the limiting nutrient for primary production within the open-ocean region. As the basin responsible for generating the densest water mass properties, i.e. Antarctic Bottom Water, and outcropping isopycnals, primary production and the associated biological carbon pump have been of long interest to the biogeochemical and climate community. We provide an independent estimate from satellite observations of the seasonal cycle in phytoplankton biomass by taking advantage of the biogeochemical Argo floats, in which we show that the biomass reaches its maximum around December in the open-ocean region. Our modelled ecosystem reaches its maximum in November, roughly a month earlier, likely due to the lack of aeolian dust input at the surface, and glacial and bathymetric sources from the south in our model. Utilizing spectral analysis and the generalized Omega equation, we decompose the eddy transport of heat and iron to its submesoscale (local) and mesoscale (remote) contributions. With the exception near the surface where mixed-layer instability is active, our results indicate that mesoscale vertical transport is of first-order significance in calculating the budgets and supplying iron across the mixed-layer base to the surface where phytoplankton can effectively photosynthesize.

Assessing the timing of seasonal movements by the prehistoric peoples of Otago has long been a problem in the archaeology of this region. The oxygen isotope ratio (18 o/16o) of mollusc shell carbonate is temperature dependent. By sampling successive increments of shell growth, palaeotemperature curves can be constructed to provide �season of death� estimates for individual shells. In this work carbonate samples from the blue mussel (Mytilus edulis) were used to estimate the seasonality of four prehistoric fishing sites. A total of 275 samples of shell material were analysed for carbon and oxygen isotope ratios at the Institute of Nuclear Sciences, Lower Hutt. Where fishing and shellfishing were important activities they were consistently associated with the winter season. A model of seasonal activity is presented for the Early part of the prehistoric period.

No description available.

Assessing the timing of seasonal movements by the prehistoric peoples of Otago has long been a problem in the archaeology of this region. The oxygen isotope ratio (18 o/16o) of mollusc shell carbonate is temperature dependent. By sampling successive increments of shell growth, palaeotemperature curves can be constructed to provide �season of death� estimates for individual shells. In this work carbonate samples from the blue mussel (Mytilus edulis) were used to estimate the seasonality of four prehistoric fishing sites. A total of 275 samples of shell material were analysed for carbon and oxygen isotope ratios at the Institute of Nuclear Sciences, Lower Hutt. Where fishing and shellfishing were important activities they were consistently associated with the winter season. A model of seasonal activity is presented for the Early part of the prehistoric period.

Thesis (Ph.D.) -- University of Western Sydney, 2002. / "A thesis presented to the University of Western Sydney for the degree of Doctor of Philosophy" Bibliography : leaves 349-363.

Thesis (doctoral) - Universität, Rostock, 2005. / Includes bibliographical references (p. [187]-214).

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 48-60).

Aspects of the ecology of B. monticularis were studied with a view to the species' conservation. This investigation indicates that the present distribution is half that of the past distribution and that only one third of the original habitat remains uncultivated. It is estimated that this area could, theoretically, support 1435 rabbits. The shrubs, Pteronia erythrocaetha and Kochia pubescens constitute the bulk of the species' diet; grasses are included in the diet whenever rainfall gives rise to new growth. Spatial use, social structure and activity pattern conform to the general leporid pattern of polygamy, solitary living and nocturnality. The breeding season extends from August to May and litters of one, possibly two, altricial young are produced after a gestation of 35-36 days. / Dissertation (MSc)--University of Pretoria, 1989. / gm2013 / Zoology and Entomology / Unrestricted