Seminars

Lecturer: M. Yamauchi (IRF)
Date: 2011-11-24 10:30
Place: Aniara

Movements of radioactive materials that is released by the Fukushima Nuclear Accident

M. Yamauchi
Swedish Institute of Space Physics

Abstract
The accident at the Fukushima Dai-ichi nuclear power plant (FNPP) that was triggered by Tohoku Earthquake on 11 March 2011 caused a release of a massive amount of radioactive material. Although the total amount of the radioactive material released by the Fukushima Accident (1017 Bq for Iodine 131I and 1016 Bq for Cesium 137Cs) is less than that from the Chernobyl disaster on 26 April, 1986, it still caused a substantial contamination of an area of several hundreds kilometer in diameter.

The radioactive fallout increases the atmospheric electric conductivity by its ionizing effect, and reduces the vertical (downward) component of the DC electric field near the ground, or potential gradient (PG). However, data from the radiation monitoring network surrounding the FNPP and PG data at Kakioka, 150 km away from the FNPP, showed independent changes compared to the radiation dose rate. The inter-regional trend of the radiation dose rate (time scale of weeks) also shows slightly different decays at different places. I compare these data to reveal the local dynamics of the radioactive dust.


Created 2011-11-07 23:22:50 by Mats Holmström
Last changed 2011-11-09 14:19:52 by Mats Holmström