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Title: Severe Nuclear Accident Program (SNAP) - a real time model for accidental releases

Conference ·
OSTI ID:466274
; ;  [1]
  1. Norwegian Meteorological Institute (DNMI), Oslo (Norway)

The model: Several Nuclear Accident Program (SNAP) has been developed at the Norwegian Meteorological Institute (DNMI) in Oslo to provide decision makers and Government officials with real-time tool for simulating large accidental releases of radioactivity from nuclear power plants or other sources. SNAP is developed in the Lagrangian framework in which atmospheric transport of radioactive pollutants is simulated by emitting a large number of particles from the source. The main advantage of the Lagrangian approach is a possibility of precise parameterization of advection processes, especially close to the source. SNAP can be used to predict the transport and deposition of a radioactive cloud in e future (up to 48 hours, in the present version) or to analyze the behavior of the cloud in the past. It is also possible to run the model in the mixed mode (partly analysis and partly forecast). In the routine run we assume unit (1 g s{sup -1}) emission in each of three classes. This assumption is very convenient for the main user of the model output in case of emergency: Norwegian Radiation Protection Agency. Due to linearity of the model equations, user can test different emission scenarios as a post processing task by assigning different weights to concentration and deposition fields corresponding to each of three emission classes. SNAP is fully operational and can be run by the meteorologist on duty at any time. The output from SNAP has two forms: First on the maps of Europe, or selected parts of Europe, individual particles are shown during the simulation period. Second, immediately after the simulation, concentration/deposition fields can be shown every three hours of the simulation period as isoline maps for each emission class. In addition, concentration and deposition maps, as well as some meteorological data, are stored on a public accessible disk for further processing by the model users.

OSTI ID:
466274
Report Number(s):
CONF-9606185-; TRN: 97:007584
Resource Relation:
Conference: 5. international conference on atmospheric sciences and applications to air quality, Seattle, WA (United States), 18-20 Jun 1996; Other Information: PBD: 1996; Related Information: Is Part Of The 5th international atmospheric sciences and applications to air quality conference; PB: 322 p.
Country of Publication:
United States
Language:
English