We modeled the global atmospheric dispersion and deposition of radionuclides released from the Fukushima Dai-ichi nuclear power plant accident. The EMAC atmospheric chemistry – general circulation model was used, with circulation dynamics nudged towards ERA-Interim reanalysis data. We applied a resolution of approximately 0.5 degrees in latitude and longitude (T255). The model accounts for emissions and transport of the radioactive isotopes <sup>131</sup>I and <sup>137</sup>Cs, and removal processes through precipitation, particle sedimentation and dry deposition. In addition, we simulated the release of <sup>133</sup>Xe, a noble gas that can be regarded as a passive transport tracer of contaminated air. The source terms are based on Stohl et al. (2012) and Chino et al. (2011); especially the emission estimates of <sup>131</sup>I are associated with a high degree of uncertainty. The calculated concentrations have been compared to station observations by the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO). We calculated that about 80% of the radioactivity from Fukushima which was released to the atmosphere deposited into the Pacific Ocean. In Japan a land area of 34 000 km<sup>2</sup> around the reactors, inhabited by nearly 10 million people, was contaminated by more than 40 kBq m<sup>−2</sup>. We also estimated the inhalation and 50-yr dose by <sup>137</sup>Cs and <sup>131</sup>I to which the people in Japan have been exposed.