Readers ask: How long will the radiation be in the reactor area after it is finally contained? Will the radiation spread across the globe via air or sea?
Science answers: Any releases of radioactivity would tend to be carried to the east across the Pacific, although day-to-day weather could spread it over considerable parts of Japan. Scientists are already forecasting the path of long-range transport through the atmosphere, as they have long practiced in order to track releases from nuclear testing and major accidents. The Chernobyl nuclear power plant accident in the Soviet Union sent radioactive dust particles hundreds and even thousands of kilometers away, with health effects occurring close in. The breadth of the Pacific would seem to be sufficient protection from detectable health effects.