Das Projekt "SIMTRAP - Simulation verkehrsbedingter Luftverschmutzung mit Hilfe von Parallelrechnern" wird vom Umweltbundesamt gefördert und von GMD-Forschungszentrum Informationstechnik GmbH, Institut für Rechnerarchitektur und Softwaretechnik durchgeführt. The objective of the SIMTRAP project is the development and demonstration of an integrated simulation system for traffic flow, traffic emissions and air pollution dispersion as a decision support tool for transport and environmental authorities. Due to the complexity of the simulated processes, the SIMTRAP system will be implemented on a distributed HPC network. The traffic flow model available in sequential form will be parallelized and coupled with a traffic emission model and an air pollution simulation system which is already implemented in parallel. As user interface a geographical information system (GIS) will be integrated to visualize input and output data, and to show the consequences of traffic control measures. After that the SIMTRAP system will be applied by potential users at four test sites to demonstrate the functionality of the system, and to validate the results gained. The test applications vary in size and objective from urban street networks in Berlin and Vienna, via a regional network in the Milan area, to an interurban highway network in the Randstad area in the Netherlands.