Quaternary history of the polar front in the Scotia sea, Antartica : foraminiferal and stable isotope evidence

• Main Author: Hale, Ruth Elisabeth
• Format: Thesis
• Language: English
• Published: University of Southampton 2001
• Subjects: Southern Ocean; Scotia Sea; Antarc*; Antarctica; antartic*; Sea ice
• Online Access: https://eprints.soton.ac.uk/464378/; https://eprints.soton.ac.uk/464378/1/787072.pdf

It can be suggested from this study that the distribution of both planktonic and benthic foraminiferal productivity is controlled by movements of the Polar Front in the Scotia Sea. It occupied a more northerly position during the last glacial stage, lying at least as far north as 52°S and possibly farther. This was also accompanies by a northward extension of the sea-ice edge and of carbonate under-saturated polar waters and hence productivity and preservation of carbonate were reduced at the core sites. At the end of the glacial stage when the climate began to warm the ice cover began to melt back, the Polar Front migrated south across the core sites, and productivity was enhanced. There is a general increase in productivity from south to north and an increase in dissolution from north to south in the Scotia Sea, and the Polar Front is a boundary across which there is a large change in these properties. The cores all seem to respond similarly at surface and deep water levels to environmental change during the last glacial transition and therefore it can be concluded that they were influenced by the same water mass and any small scale variations may be due to localised organic carbon flux to the sea floor. Comparing this study to other research from the Southern Ocean and Antarctica, the events identified here during the transition from glacial to interglacial stage seem to be at least circumpolar in extent. The connection with the northern hemisphere and therefore the global synchroneity of this transition is still not certain and would benefit from more study, particularly to the south of the Polar Front.