MET-RODOS: A Comprehensive Atmospheric Dispersion Module

A comprehensive meteorological dispersion module called MET-RODOS is being developed to serve the real-time RODOS decision support system with an integrated prediction capability for airborne radioactive spread, deposition and gamma radiation exposure on all scales. Deposition, ground level air concentrations, and ground level gamma dose rates from up to 15 simultaneous released nuclides are calculated using a nested system of local and long range atmospheric dispersion models, driven by real-time available on-line meteorological information. The MET-RODOS module uses concurrently the available source term and weather information in the RODOS data base system, and returns, up to +36h forecasts of nuclei-specific air and deposited concentrations including gamma dose rate estimations for display and subsequent processing within the RODOS framework. Weather and meteorology is available to the system via on-line connections to on-site local meteorological observations (met-towers and sodars) and via network (either public domain Internet or user-owed point-to-point ISDN) connections to remote national or international meteorological forecasting services. In its final form, scheduled for operational use in 1999, the MET-RODOS meteorological module is intended to service the RODOS system with actual and forecast (+36h) nuclei-specific air concentrations, deposition values, and gamma radiation estimates on the local, national, and European scale. provisions are furthermore being made for accommodating on-line available radiological monitoring data in the meteorological model chains in order for the module to assist with source term determination based on real-time data assimilation and back-fitting procedures.