Deep water formation

Burton, K. W., Ling, H.-F. and O Nions, R. K. (1997). Closure of the Central American Isthmus and its effect on deep-water formation in the North Atlantic. Nature 386,382-385. 

The D-O events are far too rapid to be caused by insolation changes, and they most likely result from changes in ocean circulation. Their prominence and clarity in the Greenland cores relative to the Antarctic ones is due to the proximity of Greenland to the sites of deep-water formation in the North Atlantic and the tremendous amount of heat being delivered to them by the Gulf Stream (Broecker and Denton, 1989). 

The higher the AOU, the greater the amount of O2 removed since the water mass was last at the sea smfece. Thus, AOU increases with increasing distance from the site at which the subsurfece water mass was formed. Since the AOU increases with the age of the water mass, the pathway of deep-water circulation can be traced from the distribution of AOU in the deep zone. As shown in Figure 8.2, the AOU at 4000 m is lowest in polar regions, indicating these areas are the sites of deep-water formation. 

Elliot M, Labeyrie L, Duplessy JC (2002) Changes in North Atlantic deep-water formation associated with the Dansgaard-Oeschger temperature oscillations (60-10 ka). Quat Sci Rev 21 1153-1165... 

Labeyrie LD, Juillet A (1982) Oxygen isotope exchangeabUity of diatom valve silica interpretation and consequences for paleoclimatic studies. Geochim Cosmochim Acta 46 967-975 Labeyrie LD, Duplessy JC, Blanc PL (1987) Deep water formation and temperature variations over the last 125000 years. Nature 327 477 82... 

Ar distribution in the central Arctic Ocean implications for deep water formation. Radiocarbon 36, 327-343. 

Within the polar oceans involved in deep water formation, certain regions are more important than others. The Antarctic Zone, the most polar region in the Southern Ocean, is involved in the formation of both deep and intermediate-depth waters, making this region important to the atmosphere/ocean CO2 balance. The quantitative effect of the Subantarctic Zone on atmospheric CO2 is less certain, depending on the degree to which the nutrient status of the Subantarctic surface influences the preformed nutrient concentration of newly formed subsurface water (Antarctic Intermediate Water and Subantarctic mode water), but its significance is probably much less than that of the Antarctic. 

O2 from sites of deep-water formation, O2 may penetrate uniformly 1 m or more into the sediment. 

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