Please select your home edition
Edition
Zhik Dinghy Wetsuits

Southern Ocean resistant to changing winds

by CSIRO on 24 Dec 2008
Dr Steve Rintoul, Oceanographer and climate scientist, with ARGO floats CSIRO Hobart. Photo by Bruce Miller © Copyright CSIRO Australia http://www.csiro.au

Intensifying winds in the Southern Ocean have had little influence on the strength of the Southern Ocean circulation and therefore its ability to absorb carbon dioxide from the atmosphere, according to a study published on November 23rd 2008 in Nature Geoscience.

The Southern Ocean slows the rate of greenhouse warming by removing carbon dioxide from the atmosphere and storing it in the ocean. But previous studies raised the alarm by suggesting the Southern Ocean carbon sink is now ’saturated‘ and no longer able to keep pace with increasing concentrations of carbon dioxide in the atmosphere.

The new study suggests that Southern Ocean currents, and therefore the Southern Ocean’s ability to soak up carbon dioxide, have not changed in recent decades, despite a large increase in winds.

A team of German and Australian scientists compared new ocean measurements from a global network of ocean robots with historical data from ships to determine if the Southern Ocean was changing. The study was led by Professor Claus Böning from the Institute of Marine Research (IFM-GEOMAR), Kiel.

Co-author, CSIRO’s Dr Steve Rintoul, says the Southern Ocean was found to have become warmer and fresher since the 1960s – a pattern consistent with the ‘fingerprint’ of climate change caused by carbon emissions from human activity.

'But, counter to our expectations, other aspects of the Southern Ocean have not changed despite the increase in winds,' he says. 'In particular, we found no evidence of a change in strength of the ocean currents that circle around Antarctica, or in the amount of deep water rising to the surface near Antarctica.'

'The Southern Ocean was found to have become warmer and fresher since the 1960s – a pattern consistent with the ‘fingerprint’ of climate change caused by carbon emissions from human activity' says Co-author, CSIRO’s Dr Steve Rintoul.

The fact that the upwelling of deep water has not changed is important. Deep water is very rich in carbon dioxide and so an increase in upwelling tends to transfer carbon dioxide from the ocean to the atmosphere. The low-resolution models used for climate forecasts predict stronger winds, which cause stronger upwelling and therefore less carbon dioxide being stored in the ocean.

'Our results suggest that the small-scale motions of ocean eddies act to balance the stronger winds, with no change in upwelling,' Dr Rintoul says. 'Climate models in use today cannot represent these small-scale motions and so over-estimate the response of the Southern Ocean to changes in winds.' Dr Rintoul works through the Antarctic Climate and Ecosystem Cooperative Research Centre (ACECRC) and CSIRO’s Wealth from Oceans Flagship.

Integral to the research was the Australian ocean data archive and the Argo network of ocean profilers. The data provided by the global array of more than 3,100 Argo floats is particularly valuable in remote areas like the sparsely-sampled Southern Ocean.

The research team included Professor Martin Visbeck, Astrid Dispert and Franziska Schwarzkopf from the Institute of Marine Research (IFM-GEOMAR), Kiel.

The research was initiated in Australia with funding from the Department of Climate Change, CSIRO and an Ernst Frohlich Fellowship.

The Centre for Australian Weather and Climate Research (CAWCR) click here

The Centre for Australian Weather and Climate Research is a partnership between CSIRO and the Bureau of Meteorology.


http://www.csiro.au/

Zhik Isotak Ocean 660x82upffront 660x82InSunSport - NZ

Related Articles

America's Cup World Series - Ian Roman's images of Pompey
Ian Roman was in Portsmouth for the America's Cup World Series capturing the Royal visitors Top international photographer, Ian Roman was in Portsmouth for the America's Cup World Series and provided this second of two galleries of the racing across the three days of the regatta, taking in the Royal visitors.
Posted on 26 Jul
America’s Cup World Series – More final day images by Ingrid Abery
Ingrid Abery has provided this gallery of images from final day Ingrid Abery has provided this gallery of images from final day
Posted on 25 Jul
America’s Cup World Series – Final race day images by Ingrid Abery
Ingrid Abery provided this gallery of images from final day Ingrid Abery provided this gallery of images from final day
Posted on 25 Jul
LV America’s Cup World Series - Up and down for Groupama Team France
The new leader is none other than the local team lead by Sir Ben Ainslie, who was rallied along throughout the six races 2016 America’s Cup World Series - This weekend the overall ranking for the Louis Vuitton America’s Cup World Series has been turned on its head and with the Portsmouth act complete, the new leader is none other than the local team lead by Sir Ben Ainslie, who was rallied along throughout the six races by strong support from a home crowd.
Posted on 25 Jul
LV America's Cup World Series - Land Rover BAR take two from two
While Oracle Team USA did all but everything they could to take the win with a two, one, one scorecard today 2016 Louis Vuitton America's Cup World Series - While Oracle Team USA did all but everything they could to take the win with a two, one, one scorecard today, it wasn't enough to topple the fast and furious tenacity of a Ben Ainslie led Land Rover BAR on the final day of racing at the Louis Vuitton America's Cup World Series in Portsmouth.
Posted on 25 Jul
2016 LV America’s Cup World Series - More images by Carlo Borlenghi
Carlo Borlenghi provided this gallery of images from America’s Cup World Series - Race Day 2 and Prize-giving ceremony. 2016 America’s Cup World Series - Carlo Borlenghi provided this gallery of images from 2016 Louis Vuitton America’s Cup World Series - Race Day 2 and Prize-giving ceremony.
Posted on 25 Jul
2016 LV America’s Cup World Series - Day 2 images by Carlo Borlenghi
Carlo Borlenghi provided this gallery of images from America’s Cup World Series - Race Day 2 and Prize-giving ceremony 2016 America’s Cup World Series - Carlo Borlenghi provided this gallery of images from 2016 Louis Vuitton America’s Cup World Series - Race Day 2 and Prize-giving ceremony.
Posted on 25 Jul
America's Cup - Southern Spars to build AC50 for Emirates Team NZ
Southern Spars has been appointed to build Emirates Team New Zealand’s AC50 wingsailed foiling catamaran One of the world's leading composite engineering companies, Southern Spars has been appointed to build Emirates Team New Zealand’s AC50 wingsailed foiling catamaran for the 35th America’s Cup campaign. The move marks a shift away from Cookson Boats who have been Team New Zealand's boatbuilder since 2000. No reasons have been given for the decision to change the builder.
Posted on 24 Jul
America's Cup - Emirates Team New Zealand foiled in Portsmouth
Super Sunday saw more breeze in Portsmouth today, giving all the teams the opportunity for fast racing up on their foils Super Sunday saw more breeze in Portsmouth today, giving all the teams the opportunity for fast racing up on their foils. For Emirates Team New Zealand the regatta finished as realistically expected when lining up to race against an exceptionally strong fleet with with a almost entirely rejigged crew due to Blair Tuke and Peter Burling’s absence in their build up to the Rio Olympics in the 49e
Posted on 24 Jul
LV America’s Cup World Series – Big Ben takes a big win in Portsmouth
The Duke and Duchess of Cambridge were on hand to present the awards and it was a fitting end to an amazing weekend. It really was Super Sunday for Ben Ainslie and Land Rover BAR whose second place in the last of Sunday’s three races gave them the overall regatta win at the Portsmouth event.
Posted on 24 Jul