Editors’ Note: In the March 10 article North Korea’s Punggye-ri Nuclear Test Site: Analysis Reveals Its Potential for Additional Testing with Significantly Higher Yields, by Frank Pabian and David Coblentz, we want to be clear that neither the article’s authors nor 38 North made any prediction about the expected yield of any future test at North Korea’s Punggye-ri nuclear test site. The analysis only showed that the site is potentially suitable for the conduct of larger tests than those to date, up to a maximum of 282 kilotons, as can be derived from a commonly applied formula (given the amount and type of overlying host rock found at the test site).
Moreover, there is no basis for judging North Korea’s technical capacity to conduct a test having a greater yield and there was no implication in the analysis of North Korea having such a capability.
While new activity is visible on commercial satellite imagery of Punggye-ri, as noted in a March 9 article, including additional tunneling at the North Portal, such activity only provides evidence of the potential for North Korea to conduct an additional nuclear test sometime in the future. It does not provide a basis for estimating the yield in advance of any such test.