Development of Source Term Estimation Method During Nuclear Emergency

This paper describes a new method with high response capability to estimate the release point, time and emission amount during nuclear emergency. It mainly consists of long-range atmospheric dispersion simulations and the comparison by statistical analysis of model predictions with observations at radiation monitoring points. A large number of simulations based on the possible release parameters are conducted quickly by using a vector parallel computer. The generation of input parameters for simulations and statistical analysis are carried out by Web-based graphical user interface (GUI). The performance of the preliminary version was evaluated by using dataset from the European Tracer Experiment. In the frame of emergency response, where quickness and accuracy are required, our system provided almost the same order of magnitude as the real release rate within only several hours. This performance is achieved by recently attained remarkable progress of computer technology. (author)