Jump to content

Mysterious Striped Currents In Our Oceans


Recommended Posts



Public release date: 16-Apr-2008

[ | E-mail Article ]


Contact: Claire Bowles



New Scientist


Mysterious striped currents in our oceans


IT’S amazing that nobody has spotted it before. Superimposed on every ocean on the planet there is a striped pattern of currents. Yet what causes them is a mystery.


Between 1992 and 2003, Peter Niiler of the Scripps Institution of Oceanography in San Diego, California, and colleagues collected data from more than 10,000 drifting ocean buoys, which they tracked with satellites. As expected, the buoys’ movements were influenced mainly by known global currents, which are driven by wind and by differences in the temperature and salinity of seawater.


But when the team analysed the data, it emerged that something else had been subtly influencing the buoys’ paths. It turned out that there were alternating strips of water running eastward or westward, a bit like parallel moving sidewalks. Niiler recalls his reaction: “My God, we’ve never seen these before.”


Satellite measurements showed that the interfaces between adjacent currents were alternately associated with slight peaks and troughs in sea level. When the team looked at this variation globally, they found that the 150-kilometre-wide bands covered pretty much every ocean (see Map).


To confirm that the currents were real, the team set out to measure them directly in two regions in the eastern Pacific. “Their existence is so surprising that we had to prove first that they are not an artefact of satellite data,” says Nikolai Maximenko of the University of Hawaii. Sure enough, they recorded currents flowing in opposite directions at around 40 metres per hour (Geophysical Research Letters, DOI: 10.1029/2008GL033267). This is slower than most previously known ocean currents, which may explain why the striped flows have remained undiscovered until now. “Only a very lazy canoeist would notice the effect,” says Maximenko.


The flows extend right down to the ocean floor, and the boundaries between currents are alternately associated with peaks and troughs in temperature as well as sea level. This suggests that they influence processes such as nutrient and energy flow around the oceans, but this has yet to be proven, says Niiler.


What causes the striped flows remains a puzzle. “They are a fascinating new aspect to the ocean’s circulation, but the jury is still out on the mechanisms leading to their formation,” says Geoff Vallis of the Geophysical Fluid Dynamics Laboratory at Princeton University.


He points out that similar patterns exist in atmospheric flows on other planets, for example, Jupiter. Whether similar effects are at play here is unclear, he says.




Author: New Scientist reporter Catherine Braic




UK CONTACT - Claire Bowles, New Scientist Press Office, London:

Tel: +44(0)20 7611 1274 or email claire.bowles@rbi.co.uk


US CONTACT – New Scientist Boston office:

Tel: +1 617 386 2190 or email j.heselton@elsevier.com


"This article is posted on this site to give advance access to other authorised media who may wish to report on this story, or quote extracts as part of fair dealing with this copyrighted material. Full attribution is required, and if reporting online a link to www.newscientist.com is also required. This story posted here is the EXACT text used in New Scientist magazine, therefore advance permission is required before any and every reproduction of each article in full. Please contact claire.bowles@rbi.co.uk. Please note that all material is copyright of Reed Business Information Limited and we reserve the right to take such action as we consider appropriate to protect such copyright."

Link to comment
Share on other sites

This topic is now closed to further replies.
  • Create New...

Important Information

By using this site, you agree to our Guidelines.