Antarctic Bottom Water has warmed since 1992
August 14, 2007
Deep ocean waters near Antarctica have warmed significantly since 1992, though variable temperatures may it difficult to determine whether it is a trend, reports a new study published in Geophysical Research Letters.
Measuring the temperature of water as it flows from a region near Antarctica through the Vema Channel, a narrow gorge on the seafloor about 1000 kilometers (600 miles) southeast of Rio de Janeiro, to the Brazil Basin over a 35 year-period, the researchers speculate that the current, called the Antarctic Bottom Water, has undergone slight freshening. They say more research is needed to draw further conclusions.
Meanwhile a second study published in the same issue, suggests that warmer surface temperatures in the North Atlantic may affect the strong current that encircles Antarctica.
CITATIONS: Walter Zenk and Eugene Morozov (2007). Decadal warming of the coldest Antarctic Bottom Water flow through the Vema Channel. Geophysical Research Letters August 14, 2007
Neven S. Fuckar and Geoffrey K. Vallis (2007). Interhemispheric influence of surface buoyancy conditions on a circumpolar current. Geophysical Research Letters August 14, 2007