Since the 3-11-11 earthquake/tsunami that rolled Japan, The Reactors at Fukushima Daiichi have been spewing radioactive isotopes into the air and water.
Here are some sites to keep an eye on the situation:
http://netc.com/ To watch CPMs world wide.
http://earth.nullschool.net/#current...3.26,30.81,298 To watch wind patterns world wide.
http://www.stormsurfing.com/cgi/disp...cgi?a=glob_250 To watch the jet stream.
I check these every day to gauge the safety (or lack thereof) of extended outdoor time or leaving windows open.
Every time there is an Earth quake, Typhoon, Or hiccup in that part of the world I watch with baited breath to see what will happen. On high CPM days I close up the windows to be on the safe side, And I don't spend any more time outside than I have to.