Evidence for a link between atmospheric thermonuclear detonations and nitric acid

Suitably located glacier cores, obtained from high-altitude, low-temperature sites, can reveal detailed information about atmospheric air chemistry at sub-annual resolution¹. Such data may provide input to climate-change models, the study of acid precipitation patterns and many other phenomena. Here I present data from an ice core which show that during the era of intense atmospheric thermonuclear weapons testing (ATWT) a significant part of the nitrate content in the snow was modulated by the intensity of the nuclear detonations. The fixation of nitrogen by nuclear fireballs leads to NO_x gases in the atmosphere² and ultimately to nitric acid in precipitation. At certain concentrations, these gases and the associated aerosols may perturb the climate^3,4.