The International Union of Geodesy and Geophysics (IUGG) is an international nongovernmental, nonprofit scientific union founded in 1919 that advances, promotes, and communicates knowledge of Earth, its space environment, and the dynamical processes causing change. Through eight constituent scientific associations, IUGG coordinates international research cooperation, education, assemblies, workshops, observations, policy liaison, and capacity building across geodesy, geomagnetism, aeronomy, hydrology, meteorology, oceanography, seismology, volcanology, and related Earth-and-space sciences.