For many observatories recording high-energy cosmic rays, gamma rays, or neutrinos, the Earth’s atmosphere is either an integral part or at least a considerable aspect of the detector setup. After giving an overview of the influence of the atmosphere and its variability on the development of the observed particle cascades and the signals detected from them, atmospheric monitoring strategies implemented by the different observatories are described. Examples of the impact of
atmospheric parameters and profiles on the core data of these observatories are given and technical aspects of long-term and partially very laborious monitoring efforts of the Earth’s atmosphere are discussed. Due to the per se interdisciplinary character of atmospheric monitoring in astroparticle physics, several new projects beyond the core physics of the astroparticle physics observatories
have evolved and some are reviewed in this presentation.