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Ocean Research


March 2012 Issue

Google Updates its Ocean Maps With New Imagery Data
Google has updated ocean data in its Google Earth application with more accurate imagery using bathymetry data from research cruises by the Scripps Institution of Oceanography, NOAA and ocean mapping groups.

After the update in February, Google Earth now has 15 percent of its seafloor imagery derived from shipboard soundings at 1-kilometer resolution, a 5 percent increase from previous versions, the Scripps Institution of Oceanography said.

'The original version of Google Ocean was a newly developed prototype map that had high resolution but also contained thousands of blunders related to the original archived ship data,' said David Sandwell, a Scripps geophysicist. '[University of California, San Diego] undergraduate students spent the past three years identifying and correcting the blunders as well as adding all the multibeam echosounder data archived at the National Geophysical Data Center in Boulder, Colorado.'

The new Google map now matches the map used in the research community, Sandwell said. For example, the updated map corrects a part of the seafloor that was misinterpreted in the media as evidence of the lost city of Atlantis off the coast of North Africa. For more information visit scrippsnews.ucsd.edu.

Thickest Parts of Arctic Ice Cap Melting Faster, NASA Finds
The oldest and thickest Arctic sea ice is disappearing at a faster rate than the younger and thinner ice at the edges of the Arctic Ocean's floating ice cap, making Arctic sea ice more vulnerable to further decline in the summer, according to a NASA study published in Journal of Climate in February.

The study examines how multiyear ice (ice that has made it through at least two summers) has diminished with each passing winter over the past three decades. Multiyear ice extent is diminishing at a rate of '15.1 percent per decade, and multiyear ice area, which disregards areas of open water among ice floes and focuses exclusively on the regions of the Arctic Ocean that are completely covered by multiyear ice, is shrinking even faster than multiyear ice extent, by '17.2 percent per decade. The study used a 32-year time series of multiyear ice from passive microwave data from NASA's Nimbus-7 satellite and the Meteorological Satellite Program, taken during the winter months from 1978 to 2011.

'It would take a persistent cold spell for most multiyear sea ice and other ice types to grow thick enough in the winter to survive the summer melt season and reverse the trend,' Joey Comiso, study author and senior scientist at NASA Goddard Space Flight Center, said.

Multiyear sea ice hit its record minimum extent in the winter of 2008, when it was reduced to about 55 percent of its average extent since satellite measurements of the ice cap began in the late 1970s. Multiyear sea ice then recovered slightly in the three following years, ultimately reaching an extent 34 percent larger than in 2008, but it dipped again in winter of 2012, to its second lowest extent ever.

Comiso also detected a periodic nine-year cycle where sea ice extent would grow for a few years, then shrink until the cycle restarted. This cycle is reminiscent of the Antarctic Circumpolar Wave, which has been related to the El Niño-Southern Oscillation pattern. If this cycle were confirmed, it might explain the slight sea ice cover recovery in the three years after the 2008 historical minimum. For more information visit www.nasa.gov.

Radiation from Fukushima Debris Not Concern for Distant Shores
Debris from Japan's Fukushima Dai-Ichi nuclear power plant, which was severely damaged after the earthquake and tsunami in March 2011, will begin to wash up on U.S. shores later this year. Many have asked whether the debris will pose a radiation risk, and researchers from Oregon State University (OSU) have found the simple answer to be no.

Most of the discharge that was of concern was radionuclides of iodine and cesium, deposited on widely dispersed, floating marine debris. Most of the iodine will have disappeared due to radioactive decay, and the cesium washed off and diluted in the ocean, the researchers said in February. But not all of the debris that reaches the Pacific Coast of U.S. and Canadian shores will be harmless.

'The tsunami impacted several industrial areas and no doubt swept out to sea many things like bottled chemicals or other compounds that could be toxic,' Kathryn Higley, professor at OSU, said. 'People should treat these debris with common sense; there could be some things mixed in there that are dangerous. But it will have nothing to do with radioactive contamination.'

The researchers studied marine and fishery impacts near Japan soon after the incident. While the city and fields near Fukushima still have substantial contamination, the repercussions of the event in the ocean and for distant shores are much more subdued. For more information visit oregonstate.edu.

Taiwan, Russia to Establish Wave Dynamics Research Center
Several institutions from Taiwan and Russia will establish the International Wave Dynamics Research Center at National Cheng Kung University (NCKU) in Tainan City, Taiwan, NCKU announced in February.

The researchers at the new center will include members of NCKU's Tainan Hydraulics Laboratory and Re'search Center of Ocean Environment and Technology, as well as Russia's Moscow M.V. Lomonosov State University, Wave Research Center, the A.M. Prokhorov General Physics Institute, the Russian Academy of Sciences and the P.P. Shirshov Institute of Oceanology. The research center will comprise three groups: the Theoretical Laboratory of Nonlinear Wave Processes, the Experimental Laboratory of Nonlinear Wave Processes and the Laboratory of Laser and Acoustic Remote Sensing of the Ocean.

The center's research buildings, located on the Annan campus of NCKU, will span more than 12 hectares and have more than 25 Ph.D. researchers from Taiwan and Russia. For more information visit research.ncku.edu..


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