In addition, in 1993, as Phase III of Kuroshio Exploitation and utilization Research, JMSA inaugurated a seven-year plan for comprehensive study related to the subtropical circulatory system. It conducts oceanographic observations of ocean currents, water temperatures, carbon dioxide content of sea water, etc., in the subtropical sea area extending from the waters off Shikoku Island to south of Palau, twice a year, during summer and winter.
Besides this, JMSA carries out regular oceanographic observations and tracking surveys using drifting buoys to understand the oceanographic mechanism of the Antarctic Ocean. This is part of the Japan Antarctic Research Expedition program, implemented through coordination by the Scientific Committee on Antarctic Research (SCAR), a committee established within the International Council of Scientific Unions (ICSU).
Furthermore, JMSA is conducting studies to comprehend the actual condition of rising sea levels, which many believe will be caused by global warming. It makes tide level observations at its 28 tide stations nationwide and the Showa Antarctic Base. In addition, from FY 1996, it will ascertain the absolute distance from the center of the earth to the sea surface, at one site a year, over a repeating four-year cycle, by using satellite geodetic survey technology to link its oceanographic geodetic survey datum points (Chichijima Island and three other sites) and nearby tide stations.
Also, the Japan Oceanographic Data Center (JODC) is participating in the planning of studies related to the "Global Observation Information Network" (GOIN) and the problem of global warming. This effort was raised as one of the "common concerns for global cooperation" (Common Agenda) at the July 1993 U.S-Japan Framework Talks on Bilateral Trade.
(2) Pollution Surveys of Sea Water and Bottom Sediments
Since 1972. JMSA has been conducting periodic surveys of sea water and bottom sediments. The objectives of these surveys are to prevent marine pollution and collect the basic data required to protect the marine environment in the waters adjacent seas of Japan, relatively closed sea areas, and sea areas where industrial waste, such as sludge containing PCBs or heavy metals, is dumped.
In addition, from the past Japan has been conducting a continuing radioactivity survey of sea water and seabed sediments in the adjacent seas of Japan and related waters. However, to date, survey results have not discerned a situation indicating radioactive contamination of particular concern.
(3) Survey of the State of Tar Balls Adrift and Washed Ashore
JMSA has been regularly studying the situation concerning tar balls adrift and washed
