MELTWATER INPUT TO THE SOUTHERN-OCEAN DURING THE LAST GLACIAL MAXIMUM

Three records of oxygen isotopes in biogenic silica from deep-sea sedi ment cores from the Atlantic and Indian sectors of the Southern Ocean reveal the presence of isotopically depleted diatomaceous opal in sedi ment from the last glacial maximum. This depletion is attributed to th e presence of lids of meltwater that mixed with surface water along ce rtain trajectories in the Southern Ocean. An increase in the drainage from Antarctica or extensive northward transport of icebergs are among the main mechanisms that could have produced the increase in meltwate r input to the glacial Southern Ocean. Similar isotopic trends were ob served in older climatic cycles at the same cores.