Sökning: "thermohaline circulation"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden thermohaline circulation.

1. 1. Some aspects of the Atlantic ocean circulation

   Författare :Rezwan Mohammad; Peter Lundberg; Johan Nilsson; Lawrence Mysak; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Oceanography; Thermohaline circulation; Vertical mixing; Altimetry; Nordic Seas; Meteorology; Meteorologi;

   Sammanfattning : The present thesis deals with the ocean circulation from two viewpoints: Pro primo, the dependence of the global thermohaline ocean circulation (THC) on the parameterization of the small-scale vertical mixing processes in the interior of the ocean, and, pro secundo, the dynamics of the circulation in the Nordic Seas. The THC is found be crucially dependent on the parameterization of the small-scale vertical mixing, two types of which have been compared: The commonly used constant diffusivity and a, physically more plausible, stability-dependent parameterization. LÄS MER

3. 2. The thermohaline circulation during the Last Glacial Maximum and in the Present-Day climate

   Författare :Maxime Ballarotta; Kristofer Döös; David Stevens; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ocean model; circulation; LGM; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : The thermohaline circulation (THC) corresponds to the large time- and spatial-scales ocean circulation associated with the transport of heat and salt, and is known to be an important factor controlling the climate variability. The large scales involved in the THC make it difficult to observe, and therefore the synergy of numerical models and climate proxy reconstructions is particularly relevant to study the characteristics of this circulation in the present and past climates. LÄS MER

4. 3. Atmospheric and oceanic circulation from a thermodynamic perspective

   Författare :Aitor Aldama Campino; Kristofer Döös; Peter Lundberg; George Nurser; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Atmospheric circulation; Ocean circulation; Stream functions; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : The climate system is continuously transporting and exchanging heat, freshwater, carbon and other tracers in different spatio-temporal scales. Therefore, analysing the system from a thermodynamic or biogeochemical framework is highly convenient. LÄS MER

5. 4. Accelerator Mass Spectrometry of 36Cl and 129I : Analytical Aspects and Applications

   Författare :Vasily Alfimov; Göran Possnert; Ala Aldahan; Hans-Arno Synal; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Environmental technology; Accelerator Mass Spectrometry; iodine-129; chlorine-36; gas-filled magnet; radioactive tracer; Arctic Ocean; Nordic Seas; North Atlantic; thermohaline circulation; Sellafield; La Hague; Miljöteknik; Environmental engineering; Miljöteknik;

   Sammanfattning : Two long-lived halogen radionuclides (36Cl, T1/2 = 301 kyr, and 129I, T1/2 = 15.7 Myr) have been studied by means of Accelerator Mass Spectrometry (AMS) at the Uppsala Tandem Laboratory. The 36Cl measurements in natural samples using a medium-sized tandem accelerator (~1 MeV/amu) have been considered. LÄS MER

7. 5. Dynamics and Variability of the Circulation in the North-Atlantic Subpolar Seas

   Författare :Léon Chafik; Nilsson Nilsson; Tore Furevik; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

   Sammanfattning : This thesis deals with the dynamics and circulation in the northern North Atlantic and the Nordic Seas, processes of crucial importance for the mild climate of Scandinavia and Northern Europe. High-resolution ADCP scans of currents from Greenland to Scotland in the top 400 m demonstrate that the Reykjanes Ridge is a very effective separator of flow towards the Nordic and Labrador Seas, respectively. LÄS MER