Oceans thermohaline

Haug, G. H. and Tiedemann, R. (1998). Effect of the formation of the Isthmus of Panama on Atlantic Ocean thermohaline circulation. Nature, 393, 673-676. 

Zauker, F. and Broecker, W. S. (1992). Influence of interocean fresh water transports on ocean thermohaline circulation. /. Geophys. Res. 97, 2765-2773. 

Marcantonio F, Turekian KK, Higgins S, Anderson RF, Stute M, Schlosser P (1999) The accretion rate of extraterrestrial He based on oceanic °Th flux and the relation to Os isotope variation over the past 200,000 years in an Indian Ocean core. Earth Planet Sci Lett 170 157-168 Marchal O, Francois R, Stocker TF, Joos F (2000) Ocean thermohaline circulation and sedimentary 23ipa/230Th ratio. Paleoceanography 15(6) 625-641... 

Yu E-F, Francois R, Bacon M (1996) Similar rates of modem and last-glacial ocean thermohaline circulation inferred from radiochemical data. Nature 379 689-694 Zheng Y, Anderson RF, van Geen A, Fleisher MQ (2002) Preservation of particulate non-lithogenic uranium in marine sediments. Geochim Cosmochim Acta 66(17) 3085-3092. 

Yu E.-F., Francois R., and Bacon M. P. (1996) Similar rates of modern and last-glacial ocean thermohaline... 

Great Ocean Conveyor Belt. (From Philippe Rekacewicz, UNEP/GRID-Arendal (http //www.grida.no/graphicslib/detail/world-ocean-thermohaline-circulation 57ea). With permission.)... 

Rekacewicz, R. 1996. World Ocean Thermohaline Circulation. UNEP/GRID-Arendal. 

Thermohaline circulation Deep-water circulaUon caused by density differences created in the surface waters of polar regions. Cooling increases the density of the surface waters, which sink and then advect horizontally throughout the deep ocean. The water is returned to the sea surface by eddy diffusion. 

The concentration of RDOM is simply equal to the measured concentration of DOM in deep waters (>1000 m), where its apparent radiocarbon age of 4000-6000 years is substantially greater than the timescale of thermohaline circulation in the earth s oceans (Druffel et al., 1992). Bioassay experiments have been used to verify the refractory nature of DOM in the deep sea (Barber, 1968). 

Marine communities are complicated biological systems of populations of individual species. As a result of their interaction, communities are in dynamic development. Their spatial structure is mostly determined by the composition of numerous biotic and abiotic factors, which depend on the totality of oceanic parameters. The latter are determined by the laws of general circulation of ocean waters, including tides and ebbs, zones of convergence and divergence, wind, and thermohaline currents. 

The thermohaline circulation dominated by the Arctic Ocean and Nordic Seas is responsible for a considerable part of the Earth s poleward heat transport and may also serve as a sink for CO2. Alterations of this circulation, as have been observed during climatic changes of the past, can affect global climate and in particular the climate of Europe and North America. ... 

Calculations of anthropogenic (greenhouse) climate change show that thermohaline circulation (THC) in NH oceans may weaken in the future. However, even the models that show this weakening still demonstrate that greenhouse warming in Europe will persist. So far, no one knows whether irreversible collapse of THC is a possibility or which threshold conditions correspond to such a collapse. No existing model predicts total cessation of THC for the next 60 years. 

A shutting down of the large-scale circulation of the oceans (the so-called thermohaline ocean current) would probably require a 3-degree Celsius increase during this century. The extent of the disruption that would result for societies and ecosystems is uncertain but it could, for instance, result in permanent loss of the Gulf Stream, which helps warm western Europe. 

The features of the thermohaline structure of the Black Sea waters represent the clear manifestations of the uniqueness of its nature on the whole. Most of them are related to the very restricted water exchange of the Black Sea with the adjacent parts of the World Ocean (the Sea of Marmara and the Sea of Azov), because of which its external water budget is generally small [33]. 

The main distinctive property of the Black Sea is its inland location and high isolation from the World Ocean. Because of this, formation of the sea hydrological regime and water structure is governed by the outer factors the fluxes of heat, moisture and wind stress via the sea surface, as well as the river runoff. In this connection, the sea is characterized by a high level of its environmental variability. At the same time in different parts of the Black Sea, the influence of the outer factors is very unequal. Therefore, these factors exert a different impact on the formation of hydrological fields and vertical thermohaline structure in the sea. All this confirms the necessity for... 

The density of the water controls the deepwater circulation. If the density of a water body increases, it has a tendency to sink. Subsequently, it will spread out over a horizon of uniform circulatory system is also known as thermohaline circulation. As shown in Figure 5 of the ocean conveyor belt, the densest oceanic waters are formed in Polar Regions due to the relatively low temperatures and the salinity increase that results from ice formation. Antarctic Bottom Water (ABW) is generated in the Weddell Sea and flows northward into the South Atlantic. North Atlantic Deep Water (NADW)... 

Figure 5 A schematic diagram of the thermohaline circulation of the world ocean, also know as the great ocean conveyor belt, highlighting polar regions of deepwater formation, deepwater circulation eastward from the poles and the returning westward surface water flow (Adapted from IPCC, 2001. )...

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