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 +36 hour 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-owned 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 (+36 hour) 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. (orig.)