Scariest animated GIF ever: Path of radiation leakage in Japan | Hacker News Reader

Scariest animated GIF ever: Path of radiation leakage in Japan

spiegel.de

5 pointsjawns9 comments

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I found the original article where this image appears. This is a simulation, not a measurement of the actual radiation.

Original Article (German) http://www.spiegel.de/wissenschaft/natur/0,1518,750835,00.ht...

Google Traslation: http://translate.google.com.ar/translate?js=n&prev=_t...

EDIT: More information

The Original Original Article is from ZAMG. They have many updates and variations. I will link only two:

The I-131 in the title means Iodine-131. They have the linked map and a wordwide map of the (simulated) distribution of C-137 (Caesium-137): http://translate.google.com.ar/translate?js=n&prev=_t...

Simulation of the radioactive material distribution if they do a short-term release whith optimal winds and if they do a continual release with changin winds: http://translate.google.com.ar/translate?js=n&prev=_t...

No, what's scary is that there are people who think radiation is measured in cubic millimeters (m^-3). I'm not about to claim it's a well-made chart, but nobody should be drawing any conclusions from any chart without knowing what it's measuring (a plume) or what the units are (m^-3).

"units m^-3" is another way of saying "units per m^3", i.e. radiation per cubic metre. For comparison, speed is "m s^-1" and acceleration is "m s^-2".

Radiation per cubic millimetre would be "units mm^-3".

Looks like more irrational fear-mongering akin to http://stevebeckow.com/2011/03/nuclear-fallout-map-fraud/

Who is the original source?

Well, der Spiegel is a well-known German newspaper...

What are the units on this?

And how much is dangerous?

http://en.wikipedia.org/wiki/Sievert

But I don't know how many Sieverts the map represents. Or if it's even depicting rate of dose over time.

The caption mentions "units/m^3", which would seem to indicate that the "units" would be some sort of particle count, and the colors on the map are particulate density? Just a guess, though. Radiation dosage wouldn't typically be given in units per volume, would it?

If we assume (no idea if this is accurate) that the units are proportionally related to radiation dosage, though, and correlate them with other reports, the map bands might be roughly nano-sieverts per hour.

Completely rough and unreliable calculation to arrive at that: This animation shows a plume over the Tokyo area in the 10^3 to 10^4 units range on March 15, and peak values over the plant in the 10^5 to 10^6 units range. Other reports have radiation in Tokyo peaking roughly on the order of 1 micro-Sv, and levels at the plant on the order of hundreds of micro-Sv. So if the units were nano-Sv per hour, the orders of magnitude are about right.

Not sure what the total release given as "0.10E+19 Units" at the top would mean then. Anyway, why would someone make a technical-looking graph where everything is labeled in mysterious "units"?

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