SPEEDI is a streams information from a national network of detectors of the Nuclear Safety Division of the Ministry of Education, Culture, Sports, Science and Technology (MEXT). The network was built in 1986 at a cost of $140 million (11 billion yen).
In case of a radiological emergency, the system provides real-time forecasts by analyzing the data produced by a network of detectors scattered all over Japan. The Japanese government has published the SPEEDI data only on March 23, 2011.
Maps of environmental radioactivity based on SPEEDI
Realtime radiation data collected by the MEXT via the SPEEDI.
The map does not provide the data collected for Miyagi (Jan. 2012) and up to June 2011 did not provide the data for Fukushima.
The values are expressed in nanoGray per hour (nGy/h).
Ministry of Education, Culture, Sports, Science and Technology (MEXT). Real-time updates.
Interactive map of the maximum levels of radioactivity in the Prefectures of Japan based on data generated by SPEEDI, provided by MEXT and updated for April 1, 2011.
The values are expressed in nanoGray per hour (nGy/h). The map also shown numbers of the population by prefecture.
Target Map, April 1, 2011.
Related pages
- Maps of the radiactive pollution in Japan.
- Maps based on CTBTO data.
- Wiki Maps.
- Radiations Units and Doses


Except where otherwise noted, this work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License




Pingback: SPEEDI « Fukushima Life