Abstract
The International Monitoring System is being set up aiming to detect violations of the Comprehensive Nuclear-Test-Ban Treaty. Suspicious radioxenon detections were made by the International Monitoring System after the third announced nuclear test conducted by the Democratic People’s Republic of Korea (DPRK). In this paper, inverse atmospheric transport and dispersion modelling was applied to these detections, to determine the source location, the release term and its associated uncertainties. The DPRK nuclear test site was found to be a likely source location, though a second likely source region in East Asia was found by the inverse modelling, partly due to the radioxenon background from civilian sources. Therefore, techniques to indirectly assess the influence of the radioxenon background are suggested. In case of suspicious radioxenon detections after a man-made explosion, atmospheric transport and dispersion modelling is a powerful tool for assessing whether the explosion could have been nuclear or not.
Highlights
M is the source-receptor-sensitivity matrix[38,40] and ε is the combined observation and model error
With the above considerations in mind, we selected all 133Xe observations taken between 5 April 2013 and 15 April 2013 for the IMS noble gas stations RN20, RN38, RN45 and RN58
With Flexpart, it is possible to perform a backward calculation for each observation used in the inverse modelling; the result is the source-receptor-sensitivity matrix M, thereby avoiding the need to rerun the atmospheric transport model during the optimisation: only the source term x(x, y, z, t) must be varied until Eq 2 holds
Summary
M is the source-receptor-sensitivity matrix[38,40] and ε is the combined observation and model error. Forward modelling is often used to calculate Mx after selecting an initial guess source term x. With Flexpart, it is possible (and, if the source location is not known, more efficient) to perform a backward calculation for each observation used in the inverse modelling; the result is the source-receptor-sensitivity matrix M, thereby avoiding the need to rerun the atmospheric transport model during the optimisation: only the source term x(x, y, z, t) must be varied until Eq 2 holds
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
