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5 December 2013 11:26 am ,
Vol. 342 ,
At age 30, Dutch biologist Freek Vonk has built up a respectable career as a snake scientist. But in his home country,...
Since arriving on the island of Guam in the 1940s, the brown tree snake ( Boiga irregularis ) has extirpated native...
An animal rights group known as the Nonhuman Rights Project filed lawsuits in three New York courts this week in an...
Researchers have been hot on the trail of the elusive Denisovans, a type of ancient human known only by their DNA and...
Thousands of scientists in the Russian Academy of Sciences (RAS) are about to lose their jobs as a result of the...
Dyslexia, a learning disability that hinders reading, hasn't been associated with deficits in vision, hearing, or...
Exotic, elusive, and dangerous, snakes have fascinated humankind for millennia. They can be hard to find, yet their...
Researchers have sequenced and analyzed the first two snake genomes, which represent two evolutionary extremes. The...
- 5 December 2013 11:26 am , Vol. 342 , #6163
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Fukushima Radiation: Modeling Shows Limited Spread in Ocean
4 April 2011 5:09 pm
Daily computer simulations are suggesting that, so far, the hazardous radioactive materials being released into the sea by the Fukushima nuclear plants are still largely restricted to areas near the coast. In the model being run by French researchers, the powerful Kuroshiro current—the Pacific's version of the Gulf Stream—tends to block contaminated seawater from flowing southward toward Tokyo Bay while picking up little contamination itself.
Figuring out where Fukushima radioactivity is going involves all the complexities and uncertainties that plagued early efforts to model the meanderings of oil last summer in the Gulf of Mexico, and then some, says ocean modeler Claude Estournel. She is a member of the SIROCCO group at the University of Toulouse in France running the SYMPHONIE-NH ocean model under the auspices of the French national research agency CNRS. The International Atomic Energy Agency requested that the group run its model centered on the Fukushima plant on the coast northeast of Tokyo. The resulting daily simulations posted on the Web are rife with uncertainties, Estournel cautions, so that the group is presenting only "scenarios of dispersion" that provide an "orders of magnitude" idea of the actual amounts of radionuclides in the sea.
Caveats aside, the modeling is strongly confirming oceanographers' intuition. The highest concentrations in the model are still within 5 kilometers or so of shore but have been carried up to 50 kilometers north and south by wind-driven currents. That contamination was released directly into the sea.
Radionuclides first released into the atmosphere only to fall into the sea are 20 to 100 times less concentrated but spread more widely, spanning 600 kilometers along the shore and reaching 150 kilometers offshore. In the model, concentrations are 1000 times lower than near Fukushima in the Kuroshiro as it shears off the southern extent of contamination and heads east into the Pacific. The modeling will guide Japanese authorities as they scramble to sample the expanse of ocean liable to contamination.