APOLLO2 is a long range Lagrangian particle dispersion model integrated into ARIES (Accidental Release Impact Evaluation System), the system that I.S.P.R.A. (Italian National Institute for Environmental Protection and Research) developed to provide prognosis about the dispersion of radioactive clouds in case of nuclear accidents. The model performances have been evaluated qualitatively and quantitatively against the observations of the first release of the European Tracer Experiment (ETEX). The global analysis showed a FA2=56%, a FA5=78%, and a good agreement for intermediate values within the Q-Q plot. Considering a total of 126 stations, the number of locations where NMSE<10, PCC>0.7 and FMT>20% is respectively 91, 65 and 86. The capability of APOLLO2 to predict arrival time, cloud duration and time of peak is comparable to the one shown by similar models.
Additional information about the APOLLO2 model is available in this paper:Bellasio R., S. Scarpato, R. Bianconi and P. Zeppa (2012) APOLLO2, a new long range Lagrangian particle dispersion model and its evaluation against the first ETEX tracer release. Atmospheric Environment, 57, 244-256