Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 12 of 12 for “"Freshwater forcing"”.
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Self sustained thermohaline oscillations and their implications for biogeochemical cycles
… The 'haline mode', obtained with enhanced freshwater flux and reduced vertical diffusivity, is inherently unstable, flushed by thermally-driven polar convection every few thousand years. A 3-box model of the thermohaline circulation is developed to study the basic physical mechanism of …
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The Reversibility/irreversibility of the Thermohaline Circulation After Its Shutdown: Simulations From a Hierarchy of Climate Models
… of the nonlinear response of the THC to external freshwater forcing. In this study a suite of models are used to investigate the nonlinear response of the THC to freshwater addition. It is found that the THC simulated by an ocean general circulation model responds very differently depending on …
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The production of temperature and salinity variance and covariance : implications for mixing
Large-scale thermal forcing and freshwater fluxes play an essential role in setting temperature and salinity in the ocean. A number of recent estimates of the global oceanic freshwater balance as well as the global oceanic surface net heat flux are used to investigate the effects of heat- and …
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The production of temperature and salinity variance and covariance : implications for mixing
Large-scale thermal forcing and freshwater fluxes play an essential role in setting temperature and salinity in the ocean. A number of recent estimates of the global oceanic freshwater balance as well as the global oceanic surface net heat flux are used to investigate the effects of heat- and …
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Impacts of double-diffusive processes on the thermohaline circulation
… diapycnal diffusivity. For any given external forcing, there is only one equilibrium state for the thermohaline circulation. (b) Under "flux" boundary conditions, there is a half power law dependence of the meridional overturning rate on the diapycnal diffusivity. Only one mode is possible for …
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Impacts of double-diffusive processes on the thermohaline circulation
… diapycnal diffusivity. For any given external forcing, there is only one equilibrium state for the thermohaline circulation. (b) Under "flux" boundary conditions, there is a half power law dependence of the meridional overturning rate on the diapycnal diffusivity. Only one mode is possible for …
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Dynamics of Greenland’s glacial fjords
… most recent studies focus on glacial buoyancy forcing, there are other drivers – e.g. tides, local wind, shelf variability – that can be important for fjord circulation. Using moored records from two major Greenlandic fjords, shelf forcing (from shelf density fluctuations) is found to dominate …
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Abrupt climate change in the Atlantic Ocean during the last 20,000 years : insights from multi-element analysis of benthic and planktic foraminifera and a coupled OA-GCM
… with the response of a coupled OAGCM to a freshwater perturbation? To address these questions, analytical methods were implemented for the simultaneous measurement of Mg/Ca, Zn/Ca, Cd/Ca, Mn/Ca and All Ca in foraminiferal samples using inductively-coupled plasma mass spectrometry. Paired …
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Dynamics of Greenland's glacial fjords
… most recent studies focus on glacial buoyancy forcing, there are other drivers - e.g. tides, local wind, shelf variability - that can be important for fjord circulation. Using moored records from two major Greenlandic fjords, shelf forcing (from shelf density fluctuations) is found to dominate …
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Holocene climate and environmental dynamics on the Tristan da Cunha island group, South Atlantic
… response to the weaker circulation induced by freshwater forcing in the North Atlantic. Tristan da Cunha was discovered in 1506 AD by Portuguese explorers and their arrival is clearly seen in the pollen diagram. The introduced species Plantago lanceolata appears around 1550 AD. The seal hunting …
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Innovative water tracers and water isotopes enhance Antarctic research with climate models
… by a climate model HadCM3 with a 3000-year freshwater forcing over the North Atlantic. These results highlight the importance of transient features of the early last interglacial climate. This thesis advances our understanding of the drivers on Antarctic precipitation, moisture source …
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Long-term variability and change of the Atlantic Meridional Overturning Circulation in a hierarchy of climate models
L'abstract è presente nell'allegato / the abstract is in the attachment