There is talk of North Korea testing an H-Bomb over a desolate part of the Pacific. That may be more of a demo than a test. My first thoughts upon hearing of this are in regard to the effects on the environment. Underground test are bad enough, but an open air explosion, really?!! Like we don't have enough problems.
Though curious about the open air test or demonstration, I would like to leave the thread open to cover any kind of nuclear weapons testing and the near and far impacts.