Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Arctic expeditions find giant mud waves, glacier tracks

14.12.2007
Scientists gathering evidence of ancient ice sheets uncovered a new mystery about what's happening on the Arctic sea floor today.

Sonar images revealed that, in some places, ocean currents have driven the mud along the Arctic Ocean bottom into piles, with some “mud waves” nearly 100 feet across.

Around the world, strong currents often create a wavy surface on the ocean bottom. But scientists previously thought the Arctic Ocean was too calm to do so.

Leonid Polyak, a research scientist at Byrd Polar Research Center at Ohio State University, said that it's too early to know how the waves formed.

“The mud waves could be caused by tidal fluctuations,” he said. “But that's really just speculation at this point.”

Polyak was one of the leaders of an international scientific expedition that crossed the Arctic Ocean in 2005, and he was part of a recent icebreaker expedition in 2007. Both missions took images of the ocean bottom with sonar and drew sediment cores from the ocean bottom.

Now that the sediment cores -- more than 1,000 feet in total -- are stored in a refrigerated facility of the Byrd Polar Research Center on the Ohio State campus, Polyak and his colleagues have begun their analysis.

Martin Jakobsson of Stockholm University in Sweden -- a team member and leader of the geology party in the 2007 expedition -- summarized the early findings of both sonar surveys Thursday, December 13, 2007, at the American Geophysical Union meeting in San Francisco . The presentation was part of a session on Arctic Ocean environmental history, and a related poster session was scheduled for Friday morning.

The 2005 Healy-Oden Trans-Arctic Expedition (HOTRAX) -- a cooperative effort between the United States Coast Guard Cutter Healy and the Swedish icebreaker Oden -- was the first scientific expedition to transit the entire Arctic Ocean in the direction from Alaska to Scandinavia . The scientists took sediment cores from 29 sites along the way.

For the 2007 Lomonosov Ridge off Greenland (LOMROG) expedition, the Oden joined with a Russian nuclear icebreaker called 50 let Pobedy (“50 Years of Victory”) to explore a smaller, difficult to access region of the Arctic Ocean near Greenland.

Both expeditions took images of the ocean bottom with a sonar system that also allowed them to view layers of sediment up to 1000 feet below ground.

The purpose of HOTRAX and LOMROG was to gather a sediment record of how the Arctic has changed over time, and also to find evidence of the ancient ice sheets that helped shape the Arctic Ocean seafloor. Scientists hope to use what they learned to better understand how water is exchanged between the basins, and how the Arctic affects (and is affected by) global climate systems.

This is a critical time for the Arctic, Polyak said. In the summer of 2007, much less ice covered the region than during any other time in the last century.

“Even a couple of years ago, we wouldn't have predicted that so little ice would cover the Arctic Ocean ,” he said. “It really looks like we may be living in a completely different world 20 to 30 years from now, with no ice in the Arctic in summer at all.”

The expeditions proved that giant ice masses once covered the arctic -- ice flows massive enough to scrape the ocean bottom half a mile deep. Sonar clearly showed the parallel grooves that ice flows carved in the sea floor, and boulders and other debris that the ice left behind.

As the scientists study the sediments and images in detail, they will focus on more recent Earth history -- specifically the last 150,000 years -- to find out how conditions during warm periods in the recent past resemble what we will likely have in the near future.

The mud waves that they spied on the ocean floor are another mystery, one that the scientists haven't begun to probe.

“Frankly, we have so much material to go through, and we've only just started,” Polyak said. “The goal is to establish a climate record in the sediments. To figure it out, we'll go through the cores centimeter by centimeter.”

The 2005 expedition was funded by the National Science Foundation, the Swedish Polar Research Secretariat, and the Swedish Science Council.

Leonid Polyak | EurekAlert!
Further information:
http://www.osu.edu

More articles from Earth Sciences:

nachricht Ice cave in Transylvania yields window into region's past
28.04.2017 | National Science Foundation

nachricht Citizen science campaign to aid disaster response
28.04.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>