Computer simulation modelling plays a key role in environmental studies. Numerical simulation techniques, when successfully calibrated and properly applied, allow a numerical representation of the main environmental phenomena and substantially improve our understanding of the complex interactions among the different parameters. Simulation models are capable of providing an objective evaluation of the consequences of future growth and pollution control scenarios. This book contains the edited proceedings of a seminar on environmental modelling. It provides a comprehensive overview of current environmental problems and the progress achieved in their numerical simulation. Each chapter emphasizes the application of new computer technologies such as supercomputers and graphical workstations, and the use of advanced software tools for real-time user friendly interactions between the models and the user.