Antarctic seafloor mapped in detail for the first time



Antarctic seafloor mapped in detail for the first time Berlin: Scientists have for the first time created a digital map of the entire Antarctic seafloor, and it will soon be freely available on-line to researchers.

An international team of scientists under the leadership of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research mapped the entire Antarctic seafloor in detail.

The International Bathymetric Chart of the Southern Ocean (IBCSO), for the first time shows the detailed topography of the seafloor for the entire area south of 60 degree S.

An article presented to the scientific world by IBCSO has appeared in the scientific journal Geophysical Research Letters.

The IBCSO data grid and the corresponding Antarctic chart will soon be freely available on the internet and are intended to help scientists amongst others to better understand and predict sea currents, geological processes or the behaviour of marine life.

"For our IBCSO data grid, scientists from 15 countries and over 30 research institutions brought together their bathymetric data from nautical expeditions. We were ultimately able to work with a data set comprising some 4.2 billion individual values," said IBCSO editor Jan Erik Arndt, bathymetric expert at the Alfred Wegener Institute in Bremerhaven.

Reliable bathymetric data have so far existed for only 17 per cent of this area. The largest data gaps, for example, are in the deep sea regions of the south Indian Ocean and the South Pacific and in areas which experience difficult sea ice conditions throughout the year in some places, such as in the Weddell Sea, Arndt said. Where older models only offer a glimpse of a mountain in the deep sea, IBCSO shows an elevation with sharp ridge crests and deep channels in the slopes.

A formerly flat point at the bottom of the Riiser-Larsen Sea can now be identified as an offshoot, some 300 metres deep, of the underwater Ritscher Canyon which runs along a length of over 100 kilometres from the south west to the north.

And not far away from today's shelf ice edge of the large Getz ice shelf the furrows are to be seen quite clearly which were ploughed into the seafloor by the ice tongue as it grew.

PTI