A world grid of vertical cosmic ray cutoff rigidities was calculated using the Definitive International Geomagnetic Reference Field for Epoch 2000.0. These cutoff rigidity values were specifically computed for updating the aircraft radiation dose. These cutoff rigidity values show the effects of the continued evolution of the geomagnetic field. The average cutoff values continue to decrease especially in the South Atlantic and South American areas. However, in the North Atlantic and the east coast of the North American continent, the cutoff values are increasing.

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 1 (SH), pages 737-740