Clarification of Antarctic Bottom Water circulation in the Indian sector of Antarctic, particularly direct observation of its meridionall volume transport

点击翻译按钮获取中文摘要

The Southern Ocean plays an important role on global climate through the directl heat and mass connections with Pacific Ocean, Atlantic Ocean and Indian Ocean. Especially, it is well known that the Antarctic Ocean is the largest seasonal sea ice zone in the world and produces the Antarctic Bottom Water (AABW) which is one of sources for general deep ocean circulation. In spite of its importance in earth sciences, there is very few direct observation for the meridional volume transport of AABW and its seasonal variations. It is widely believed that the AABW is produced in three coastal regions in the Weddell Sea, Ross Sea and off the Adelie coast. Recently, observational plans on the AABW formation are preceeded to have in the Weddell and Ross Seas by US and Europian oceanographers.The purpose of this study is to quantitatively evaluate the meridional volume transport of AABW (hereafter called to the Adelie AABW) which should be produced in the coastal polynyas off the Adelie coast by direct observations through a joint program with CSIRO in Australia. A recent result of numerical simulation on global ocean circulation suggests that the Adelie AABW may be the important source of Pacific and Indian Ocean deep water. We have deployed mooring systems with about 30 current meters and CT meters at 8 stations east of the Kerguelen Plateau for two years from February 2003 to February 2005, to observe the meridional volume transport of Adelie AABW as a werstern boundary current and its seasonal variations. We could successfully recover all the current and CT instrument mooring systems. We have now numerous valuable data. Since we fortunately could obtain a new research fund on ou study of the Adelie AABW formation, we are planning to progress analyzes of numerous and valuable data and would like to evaluate the meridional heat and volume transport of the Adelie AABW and its seasonal variability quantitatively.