[M-AG32] CTBT IMS Technologies for Detecting Nuclear Explosion and Their Applications to Earth Science

[MAG32-P01] Verification of the source term estimation method using atmospheric transport modelling for nuclear tests

*Akiko FURUNO¹, Yoichi Yamamoto¹, Yutaka Tomita¹, Kurihara Toshiyuki¹ (1.Japan Atomic Energy Agency)

Keywords:CTBT, FLEXPART, Source term estimation

We have presented about the source term estimation method of airborne radionuclides using forward tracking simulations of an atmospheric transport modelling. In this method, adequate candidates about release points and release start times are set for a high concentration detection event, and dispersion simulations are performed using these candidate as initial conditions. The obtained concentration distributions are compared with the IMS data, and the initial conditions that produce the calculation results closest to the observation are extracted as the "release sources". Several statistical methods for extraction have been published in previous studies, but for the purpose of nuclear test detection, a method that is compatible with the spatial-temporal resolution of the CTBTO's international monitoring system (IMS) network is required. In this presentation, we validate the method of estimating release points by forward tracking calculations for the third nuclear test conducted by North Korea in 2013.