The purpose of this post is to conduct a thought experiment to arrive at (I hope) a useful estimate of how much radioactive contamination might occur if North Korea detonates a thermonuclear weapon in the lower atmosphere over the North Pacific Ocean. There are a significant number of unknowns, not the least of which is the fundamental uncertainty as to whether the rogue nation has successfully tested a Teller-Ulam style thermonuclear weapon or not. I explain my assumptions and compare the resulting global release of radioisotopes that represent a radiological health concern from such a test to the amounts recently released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) disaster, the Chernobyl disaster and aggregate atmospheric weapons testing in the last century. I invite comments and an accounting of the approach used here and how it might be improved. The estimates represent a worst case scenario I think as there are serious questions as to whether the North Koreans possess thermonuclear weapons similar to those tested by other countries in the past and whether or not they could deliver a weapon similar in yield to their most recent underground test to the atmosphere. I find that a North Korean test over the Pacific would likely release:
similar amounts of 90Sr but much lower 137Cs as the Fukushima Daiichi nuclear disaster to the environment more 131I than Fukushima but 2-3 fold less than Chernobyl release up to 2000-fold more Pu globally than did Fukushima but 10-100 fold less than ChernobylThe health consequences of these releases are beyond the scope of this post but would depend on (among other things) the height that the weapon was detonated in the atmosphere, the location of the detonation over the Pacific and atmospheric circulation that would all dictate where the isotopes would be deposited. The deposition distribution would determine the dose experienced by living organisms through external and internal pathways.