April 24, 2012 – Colorado.
The Japanese Ministry of Economy, Trade and Industry (METI) just published (April 23, 2012) a radiation map showing that the hardest-hit areas will continue to see dangerously high fallout-caused external radiation levels for decades to come. See maps and map source below.
METI Map of “year dose of external radiation” for March 2012 (based on aerial surveys done in November 2011); which would be almost the same for now, April or May 2012:
The grey line shows the boundary of the evacuation zone, illustrating that there are spots within that zone that aren’t as contaminated as some areas outside of it. You can zoom-in on the original pdf., but just for clairty, here’ the legend (enlarged, below), with the familiar odd map color legend choice with ‘green’ being much worse than ‘dark blue’…
To take one approximate modeled dose rate found in some areas outside the evacuation areas for the next half decade: “Green: 10 to 20 millieSievert per year” means 5 t0 10 (or even more) times normal background radiation, but not from a far-away source, but from fine radioactive dust all around you. On your Geiger Counter, it could look “benign” with a reading of, for instance, just under 2 µSv/hr, but the fact that the radiation source is in the air (unlike an X-ray or from cosmic rays during an airplane flight) makes it incomparably more health-hazardous than a dose from an X-ray or from cosmic rays.
The average annual radiation exposure from natural sources is about 3,100 microsieverts (= 3.1 mSv = 310 millirem). (Source: NRC, here.). In coastal Japan is is (or was) normally significantly less.
- See also my pages help understanding the Radiation Units, or what this could mean for Exposure Health Effects; or check current radiation levels worldwide.
! –> See the METI radiation dose maps for March 2013, 2014, 2017, 2022 and 2032:
- !–> You may also be interested in my Fallout Map Comparison between Fukushima, Fukushima and Chernobyl, USSR (Now Chornobyl, Ukraine). (Based on the MEXT fallout maps from Sept 29, 2011, with the colors “translated” to make ‘m visually comparable)
- !–> For a more comprehensive overview of this mega-disaster with ongoing nuclear catastrophe, see my two-part One-Year-Later Review.