Atmospheric transport pathways from the Bilibino nuclear power plant to Alaska

The Bilibino nuclear power plant (68 degrees 03'N, 166 degrees 20'E, 340 m asl) in northeastern Siberia is the closest Russian nuclear power plant to the USA. We used an isentropic trajectory model to estimate the probability that air in the Bilibino region would be transported to Alaska following a hypothetical accident. This estimate is based on the meteorological data f rom 1991 to 1995, Our calculations indicate that the probability that air i n the Bilibino region will be transported to Alaska is approximately 6-16%, averaged over the entire year. This probability doubles in the summer and early fall with a maximum in August of 12-33%. For the entire year the mean , median, and minimum transport times from the plant to Alaska are 4, 3.5 a nd 1 d, respectively. Since rapid transport (1-2 d) could bring air parcels containing short-lived radionuclides, these events potentially represent t he greatest risk to inhabitants of Alaska. (C) 1999 Elsevier Science Ltd. A ll rights reserved.