Featured Research

from universities, journals, and other organizations

Climate Clues In Southern Ocean: Ocean Currents Surprisingly Resistant To Intensifying Winds

Date:
December 2, 2008
Source:
Leibniz Institute of Marine Sciences (IFM-GEOMAR)
Summary:
The Antarctic Circumpolar Current is the current system with the largest volume transport in the world ocean. Between 40° and 60°S strong westerlies move about 140 million cubic meters of water per second around the Antarctic continent (this is about five times the transport of the Gulf Stream). Vertical motions associated with this current have been responsible for transporting a substantial fraction of the anthropogenic carbon dioxide emissions from the atmosphere to the deep ocean, thereby effectively damping the rate of global warming.

Schematic diagram of the circulation in the Antarctic Circumpolar Current (ACC). The ACC (red) is surrounding the Antarctic continent in eastern direction while the current shows intensive meanders and eddies (yellow). Crossways at the northern rim of the ACC large-scale downwelling of surface water to depth of app. 1000 meters takes place whereas at the south rim water is upwelled from greater depths.
Credit: Image courtesy of Leibniz Institute of Marine Sciences (IFM-GEOMAR)

The Antarctic Circumpolar Current is the current system with the largest volume transport in the world ocean. Between 40° and 60°S strong westerlies move about 140 million cubic meters of water per second around the Antarctic continent (this is about five times the transport of the Gulf Stream).

Vertical motions associated with this current have been responsible for transporting a substantial fraction of the anthropogenic carbon dioxide emissions from the atmosphere to the deep ocean, thereby effectively damping the rate of global warming.

Investigations in this key region of the world ocean have been hampered by a sparse database due to the logistical challenges for ship based expeditions in the high-latitude Southern Ocean.

“In our study we used data obtained by the international Argo Programme”, explains Prof. Claus Böning from the Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel, Germany. Argo is a system of currently 3000 autonomous free-floating robotic systems which are surveying the world ocean. Every 10 days these buoys measure temperature and salinity profiles over the upper 2000 meters. These measurements are transmitted to land stations via satellite. “For this study about 52,000 profiles of more than 600 Argo-drifters in the Southern Ocean were used and compared with historic ship measurements”, explains oceanographer Astrid Dispert from IFM-GEOMAR. For this analysis the extensive archives of the Australian marine research centre in Hobart, Tasmania were also used.

As expected, the observations in the subpolar ocean demonstrate an increase of water temperature and a decrease in salinity at the same time. Nevertheless, in contradiction to the simulations of various climate models the data show no significant changes in water transport. “Our results point to one important thing: Eddies which are currently not resolved in climate models might be the key process in controlling the transport of the ACC”, Prof. Böning explains. Hence, his conclusion is that investigations with high-resolution ocean models are required to test this hypothesis. “Of course, besides the simulations we also need further observations”, adds Prof. Martin Visbeck (IFM-GEOMAR). “Thanks to the international Argo observations programme we now have continuously access to data from a worldwide network of more than 3000 profiling-drifters. This is a quantum leap in the field of ocean observations, which, together with high resolution modelling gives us new insights about long-term changes in the ocean.“

Further investigations have to show whether the results are robust. If confirmed, this would in one way be good news: Until now the Southern Ocean is the biggest oceanic sink for anthropogenic carbon dioxide and therefore a crucial regulator for the atmospheric carbon dioxide concentration. Climate models predicted a severe reduction in the southern ocean carbon dioxide uptake due to wind-forced changes in the current fields. Now high-resolution models are needed to assess the role of the hitherto unresolved ocean eddies in the Southern Ocean’s response to the progressive changes in the atmospheric conditions.


Story Source:

The above story is based on materials provided by Leibniz Institute of Marine Sciences (IFM-GEOMAR). Note: Materials may be edited for content and length.


Journal Reference:

  1. Böning et al. The response of the Antarctic Circumpolar Current to recent climate change. Nature Geoscience, December 2008; DOI: 10.1038/ngeo362

Cite This Page:

Leibniz Institute of Marine Sciences (IFM-GEOMAR). "Climate Clues In Southern Ocean: Ocean Currents Surprisingly Resistant To Intensifying Winds." ScienceDaily. ScienceDaily, 2 December 2008. <www.sciencedaily.com/releases/2008/11/081123222842.htm>.
Leibniz Institute of Marine Sciences (IFM-GEOMAR). (2008, December 2). Climate Clues In Southern Ocean: Ocean Currents Surprisingly Resistant To Intensifying Winds. ScienceDaily. Retrieved September 14, 2014 from www.sciencedaily.com/releases/2008/11/081123222842.htm
Leibniz Institute of Marine Sciences (IFM-GEOMAR). "Climate Clues In Southern Ocean: Ocean Currents Surprisingly Resistant To Intensifying Winds." ScienceDaily. www.sciencedaily.com/releases/2008/11/081123222842.htm (accessed September 14, 2014).

Share This



More Earth & Climate News

Sunday, September 14, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Conservationists Face Uphill PR Battle With New Shark Rules

Conservationists Face Uphill PR Battle With New Shark Rules

Newsy (Sep. 14, 2014) — New conservation measures for shark fishing face an uphill PR battle in the fight to slow shark extinction. Video provided by Newsy
Powered by NewsLook.com
Pakistan's 'killer Mountain' Fails to Draw Tourists After Attack

Pakistan's 'killer Mountain' Fails to Draw Tourists After Attack

AFP (Sep. 12, 2014) — In June 2013, 10 foreign mountaineers and their guide were murdered on Nanga Parbat, an iconic peak that stands at 8,126m tall in northern Pakisan. Duration: 02:34 Video provided by AFP
Powered by NewsLook.com
Solar Storm To Hit This Weekend, Scientists Not Worried

Solar Storm To Hit This Weekend, Scientists Not Worried

Newsy (Sep. 11, 2014) — Two solar flares which erupted in our direction this week will arrive this weekend. The resulting solar storm will be powerful but not dangerous. Video provided by Newsy
Powered by NewsLook.com
The Ozone Layer Is Recovering, But It's Not All Good News

The Ozone Layer Is Recovering, But It's Not All Good News

Newsy (Sep. 11, 2014) — The Ozone layer is recovering thickness! Hooray! But in helping its recovery, we may have also helped put more greenhouse gases out there. Hooray? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

    Technology News



    Save/Print:
    Share:  

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile iPhone Android Web
    Follow Facebook Twitter Google+
    Subscribe RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins