Mainichi Daily News of June 25,2011 suggests the extent of the radioactive fallout from the Fukushima nuclear facility. I have already run various bits and pieces of information to show the range of radiactivity. This is another suggestive report.
“Radioactive materials spewed out from the crippled Fukushima No. 1 Nuclear Power Plant reached North America soon after the meltdown and were carried all the way to Europe, according to a simulation by university researchers.”
More detail from the report:
The computer simulation by researchers at Kyushu University and the University of Tokyo, among other institutions, calculated dispersal of radioactive dust from the Fukushima plant beginning at 9 p.m. on March 14, when radiation levels around the plant spiked.
The team found that radioactive dust was likely caught by the jet stream and carried across the Pacific Ocean, its concentration dropping as it spread. According to the computer model, radioactive materials at a concentration just one-one hundred millionth of that found around the Fukushima plant hit the west coast of North America three days later, and reached the skies over much of Europe about a week later.
According to the research team, updrafts in a low-pressure system passing over the disaster-stricken Tohoku region on March 14-15 carried some of the radioactive dust that had collected about 1.5 kilometers above the plant to an altitude of about 5 kilometers. The jet stream then caught the dust and diffused it over the Pacific Ocean and beyond.