Carbon Capture and Storage (CCS) is one of the possible mitigation measures to reduce the CO2 emissions produced from anthropogenic sources and thus help address the issue of global warming. Accidental CO2 releases may occur at any of the CCS stages, having potentially harmful consequences on the people who work in the CCS facilities, the general public in their vicinity and the environment. CFD is an increasingly used tool to investigate the behavior of released substances and predict the consequences of hazardous scenarios. This information aids the development of mitigation methods to minimize the consequences of an accident. The validation of numerical codes and models is a necessary preliminary step before their application to safety and risk assessment analysis. In this context, numerical simulations of CO2 release and dispersion field experiments were performed with a CFD code. The experimental data were taken from the Kit Fox CO2 gas field experiments which were designed to investigate the effect of ground roughness of industrial process plants and of meteorological conditions on the formation and extent of the CO2 gas cloud. This study presents a comparison between the simulation results and the experimental measurements in order to assess the accuracy of the code with different modeling approaches. (C) 2011 Elsevier B.V. All rights reserved.