Third international challenge to model the medium- to long-range transport of radioxenon to four Comprehensive Nuclear-Test-Ban Treaty monitoring stations

Maurer, C.*; Galmarini, S.*; Solazzo, E.*; Kumierczyk-Michulec, J.*; Bar, J.*; Kalinowski, M.*; Schoeppner, M.*; Bourgouin, P.*; Crawford, A.*; Stein, A.*; et al.

Journal of Environmental Radioactivity, 255, p.106968_1 - 106968_27, 2022/12

https://doi.org/10.1016/j.jenvrad.2022.106968

After performing multi-model exercises in 2015 and 2016, a comprehensive Xe-133 atmospheric transport modeling challenge was organized in 2019. For evaluation measured samples for the same time frame were gathered from four International Monitoring System stations located in Europe and North America with overall considerable influence of IRE and/or CNL emissions. As a lesion learnt from the 2nd ATM-Challenge participants were prompted to work with controlled and harmonized model set ups to make runs more comparable, but also to increase diversity. Effects of transport errors, not properly characterized remaining emitters and long IMS sampling times (12 to 24 hours) undoubtedly interfere with the effect of high-quality IRE and CNL stack data. An ensemble based on a few arbitrary submissions is good enough to forecast the Xe-133 background at the stations investigated. The effective ensemble size is below five.

Real-time environmental contamination assessment system during nuclear emergency

Terada, Hiroaki; Furuno, Akiko; Chino, Masamichi

Proceedings from the International Conference on Radioactivity in the Environment (CD-ROM), 4 Pages, 2002/09

The present study aims to expanding the capability of WSPEEDI, so that it can be applied to atmospheric releases of radionuclides in the world for terrorist attack as well as nuclear accident. A terrorist attack would be possible in any time, any place and any scale. Altough WSPEEDI has already had a function to acquire global meteorological forecasts to generate a geographical map at arbitrary region in the world, it had no capability for simultaneous multi-scale predictions. Thus, the combination of models, non-hydrostatic meteorological model MM5 and atmospheric dispersion model GEARN, is introduced to WSPEEDI. MM5 can forecast local and regional meteorological condition simultaneously by domain nesting calculations. By the input of meteorological condition generated by MM5, GEARN can forecast multi-scale environmental contaminations considering detailed boundary layer and precipitation processes. Using this improved WSPEEDI, we made test calculations assuming a nuclear accident or terrorist attack in Asia.

OSCAAR calculations for the Hanford dose reconstruction scenario of BIOMASS theme 2

Homma, Toshimitsu; Inoue, Yoshihisa*; Tomita, Kenichi*

JAERI-Research 2000-049, 101 Pages, 2000/10

JAERI-Research-2000-049.pdf:3.03MB

no abstracts in English

A Simulation study on long-range transport of Radon-222 over eastern Asia

Ishikawa, Hirohiko; Yamazawa, Hiromi; Chino, Masamichi; ; ;

Proc. of the Int. Conf. on Radiation Effects and Protection, p.385 - 389, 1992/00

no abstracts in English

Source estimation analysis of radioxenon detected at Mongolian radionuclide monitoring station and diffusion analysis from the emission source

Yamamoto, Yoichi; Furuno, Akiko; Kurihara, Toshiyuki; Tomita, Yutaka

no journal, , 

Radioxenon is a high-yield fission product which is an important tracer for a nuclear test, and is also emitted by civil nuclear facilities like isotope production facilities or nuclear power plants. The Ulaanbaatar radionuclide monitoring station (MNX45) in Mongolia has detected relatively high concentrations of Xe-133 exceeding 1 mBq/m several times a year, despite the fact that there are no nuclear facilities in the vicinity that could be sources of emissions. To determine the source of emission, Atmospheric Transport Modelling (ATM) backtracking analyses for source estimation were carried out for five cases with consecutive detections of Xe-133 above 1 mBq/m since September 2023. For these cases, forward tracking analyses from the estimated sources of emissions were carried out to investigate the impact of detected Xe-133 on radionuclide monitoring stations located downwind from MNX45. We report on the analysis and results.