A5040831553- Atmospheric chemistry and aerosols
- Radioactive contamination and transfer
- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Nuclear and radioactivity studies
- Radioactivity and Radon Measurements
- Meteorological Phenomena and Simulations
- Air Quality Monitoring and Forecasting
- Wind and Air Flow Studies
- Risk Perception and Management
- Astro and Planetary Science
- Planetary Science and Exploration
- Analytical Chemistry and Sensors
- Laser Design and Applications
- Space Satellite Systems and Control
- Nuclear Issues and Defense
- Water Quality Monitoring and Analysis
- Radioactive element chemistry and processing
- Atmospheric aerosols and clouds
- Fire dynamics and safety research
- Spaceflight effects on biology
- Ocean Acidification Effects and Responses
Japan Atomic Energy Agency
2016-2023
National Institute for Environmental Studies
2015-2018
To assess the radiological dose to public resulting from Fukushima Daiichi Nuclear Power Station (FDNPS) accident in Japan, especially for early phase of when no measured data are available that purpose, spatial and temporal distributions radioactive materials environment need be reconstructed through computer simulations using atmospheric transport, dispersion, deposition model (ATDM). For ATDM simulation, source term discharged into atmosphere is essential has been estimated many studies....
The third model intercomparison project (MIP) for investigating the atmospheric behavior of caesium-137 (137Cs) emitted from Fukushima Daiichi Nuclear Power Plant (FDNPP) (3rd FDNPP-MIP), Japan, in March 2011, was conducted. A finer horizontal grid spacing (1 km) used than previous FDNPP-MIP (2nd FDNPP-MIP, Sato et al., 2018; 3 to evaluate models' performance high-concentration events measured near FDNPP. Nine models 2nd were also 3rd and all identical source terms meteorological fields....
It is essential to establish a method for reconstructing the source term and spatiotemporal distribution of radionuclides released into atmosphere due nuclear accident emergency countermeasures. We examined dependency estimation based on Bayesian inference using atmospheric dispersion simulation environmental monitoring data availability various data. Additionally, we applicability this real-time conducted immediately after an accident. A sensitivity analysis estimated during Fukushima...
We have estimated source term and analyzed processes of atmospheric dispersion against discharge radioactive materials due to the Fukushima Daiichi Nuclear Power Station (FDNPS) accident by atmospheric-dispersion calculation using Worldwide version System for Environmental Emergency Dose Information (WSPEEDI). On basis this experience, we developed an method that can respond various needs prediction in a nuclear emergency provide useful information emergency-response planning. By method, if...
Abstract State-of-the-art chemistry–climate models (CCMs) have indicated that a future decrease in ozone-depleting substances (ODSs) combined with an increase greenhouse gases (GHGs) would the column ozone amount most regions except tropics and Antarctic. However, large Arctic losses occurred at frequency of approximately once per decade since 1990s (1997, 2011 2020), despite ODS concentration peaking mid-1990s. To understand this, CCMs were used to conduct 24 experiments GHG concentrations...
When assisting emergency responses to a nuclear accident through atmospheric dispersion simulations, it is necessary provide the prediction results and their uncertainties. This study develops an estimation method using machine learning for uncertainty in forecasted plume directions. The difference directions derived from meteorological forecast analysis inputs was considered as direction. Bayesian used predict based on accumulated result past cases. A three-day simulation conducted every...
To improve the atmospheric dispersion simulations of radioactive materials released due to Fukushima Daiichi Nuclear Power Station (FNPS1) accident, we adopted four-dimensional variational data assimilation (4D-Var) system (WRFDA) and confirmed effectiveness existing 4D-Var technique for reproducibility simulation during FNPS1 accident. The was performed by community meteorological model (WRF) our (GEARN). accuracy simulated 137Cs deposition patterns in area closed Ibaraki, Tochigi,...
The behaviors of atmospheric 129I and the global cycle remain incompletely understood because spatiotemporal resolution monitoring is insufficient, few measurement-based models have been reported. This study aims to quantitatively understand budget. When quantifying, we conducted dispersion simulations covering from period 2007 2010. To achieve this goal, present newly incorporates iodine chemical processes two gas-phase reactions, six photolysis heterogeneous reactions into an existing...
The source term of 137Cs from the Fukushima Dai-ichi Nuclear Power Station (FDNPS) accident was estimated results local-scale atmospheric dispersion simulations and measurements. To confirm term's validity for reproducing large-scale 137Cs, this study conducted hemispheric-scale oceanic simulations. In simulations, atmospheric-dispersion database system Worldwide version System Prediction Environmental Emergency Dose Information (WSPEEDI)-DB model SEA-GEARN-FDM that were developed by Japan...
Abstract A reduction of the total ozone over southern tip South America lasting 3 weeks occurred in November 2009. Analyses ERA‐Interim reanalysis data and observed by Ozone Monitoring Instrument indicate that event was caused a migration polar vortex toward American continent at time breakup. The is associated with an enhanced wave flux from troposphere 120–150°W 50–60°S to west stratosphere part continent, which led large negative geopotential height anomaly lower stratosphere. In...
An accurate analysis of local-scale atmospheric dispersion radioactive materials is important for safety and consequence assessments emergency responses to accidental release from nuclear facilities. It necessary predict the three-dimensional distribution plume in consideration turbulent effects induced by individual buildings meteorological conditions. In this study, first, we conducted with observations a Doppler LiDAR simple experiments mist-spraying system at site Japan Atomic Energy...