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This image shows the maximum wave heights of the tsunami generated by the Japan earthquake on March 11, 2011. It does NOT represent levels of radiation from the damaged Fukushima nuclear power plant. Credit: National Oceanic and Atmospheric Administration
What happens in Vegas may stay in Vegas, but what happens in the oceans almost never stays put. Ocean currents transport materials across vast distances. So if something unpleasant happens in one spot in the oceans, its effects may be felt thousands of miles away.
An example is the failure of nuclear reactors in Japan in 2011. A massive tsunami damaged reactors in Fukushima, releasing large amounts of radioactive material into the air and into the Pacific Ocean. The debris in the ocean quickly spread out. In fact, some of it traveled all the way to the west coast of North America.
Scientists began looking for radioactive material off North America in 2012. They were looking for two forms of cesium, a byproduct of nuclear reactions. One form decays to a non¬-radioactive element in just a couple of years, so any that showed up in American waters was likely to come from the accident. The other form lasts longer, so it shows up in higher concentrations.
The researchers found an uptick in cesium just off the Canadian shore in June of 2013. And by February of 2014, the amount of cesium had jumped to about twice the normal level. The total amount of cesium in North American waters is expected to rise to five or six times the pre-accident levels in late 2015 and early 2016.
Even so, that’s far below the levels that are dangerous to people or marine life. So the most harmful effects of the Japanese nuclear accident stayed in Japan.
