Paleoceanographic evolution and associatcd environmental history

Abstract

World ocean circulation has been playing an important role on the transport of heat energy and material on the surface of the earth and have had an intimate relation with climate. In order to discuss its evolution, four representative regimes of ocean circulations are summarized : (1) world ocean circulation in a superocean, Panthalassa during the early Mesozoic, (2) anoxic event in the young Atlantic during the late Mesozoic, (3) the evolution of Antarctic Ocean and the formation of Circum-Antarctic Current during Tertiary, and (4) ocean circulations during glacial and inter-glacial times. World ocean circulation and climate have been ultimately constrained by the land and sea distribution and botton topography. It is suggested that only a small environmental change should be amplified by the joint system of Atmosphere-Ocean-Biosphere. Fluctuations of temperature around 0°C in the high latitude would be important to those of ocean circulation and climate.