About us
The Environmental Dynamics Research Group researches and develops models, prediction systems, and analytical methods for the atmosphere, land, and oceans to assess the environmental effects of various radioactive material release and environmental contamination events.Research and development and advancement of these technologies require basic data for model validation. For this purpose, we also conduct sample collection and surveys in the ocean and on land.In addition, we are engaged in research on material circulation in the environment using radioactive materials and stable isotopes to help validate the models and prediction systems we have developed, and to help solve social issues such as global warming.
News
- 2025/02/04
- The following research result has been announced in a press release (2025.01.21).
乾燥と湿潤の繰り返しが土壌のCO2放出を増大させることを解明 (Japanease only)
- 2025/02/03
- A research paper has been published.
Suzuki Y, Hiradate S, Koarashi J, Atarashi-Andoh M, Yomogida T, Kanda Y, Nagano H (2025) Comprehensive increase in CO2 release by drying?rewetting cycles among Japanese forests and pastureland soils and exploring predictors of increasing magnitude, SOIL 11, 35-49
- 2025/02/03
- The new homepage has been released.
Research
Environmental science
digital twins
We are engaged in research and development to understand the environmental behavior of environmentally hazardous substances, including radioactive substances. We have developed models and systems to simulate the transfer process of various substances in the atmosphere, land, hydrosphere, and biosphere, and aim to understand the material circulation in each sphere. In recent years, we have been working on research and development of environmental behavior digital twins that can comprehensively evaluate the environmental behavior of substances in each sphere by combining these multiple models.
- Development of Atmospheric-dispersion database system that can immediately provide calculation results for various source term and meteorological conditions (Japanese only)
- Detailed radioactive plume dispersion and dose calculations considering buildings in local areas
-Development of a local-scale high-resolution atmospheric dispersion and dose assessment system (LHADDAS)-? (Japanese only) - What is going to happen to the radiocesium contamination of forest trees in Fukushima in the future?
-Newly developed computational model elucidated the contamination mechanism and enabled the future prediction-? (Japanese only) - Development of an emergency assessment system of the marine environmental radioactivity (Japanese only)
- Future Behavior of Radiocesium on Land
-Prediction of Radiocesium Behavior on Land for 30 Years-
Please see here for details of research topics on the old website.
Environmental material
circulation using
radioactive materials
and stable isotopes
Armed with analytical techniques for radioisotopes and stable isotopes in the environment, we are using a unique approach that uses them as tracers to understand the actual state of material circulation, elucidate mechanisms, and predict responses to climate change. We aim to evaluate the impact of substances released by human activities on the environment based on new knowledge gained from not only observations in real environments but also from laboratory experiments that simulate environmental changes, targeting a wide range of fields from forests and farmland to coastal oceans.
Carbon cycle research in forests and farmlands using radiocarbon (14C) as a tracer
- Forum for Nuclear Cooperation in Asia (FNCA) Climate Change Project
- Prediction for the future climate change impacts based on comprehensive observations of soil carbon dynamics in forests in Asia
- Digital-biosphere：Integrated biosphere science for mitigating global environment change
(Grant-in-Aid for Scientific Research; KAKENHI, Transformative Research Area [A]) [A01] Prediction of forests that maximize carbon sequestration - Evaluation for the impact of converting and expanding tropical peat forests into oil palm plantations on carbon accumulation and circulation
- Carbon sequestration and circulation functions in deep soil
- The mechanisms that determine soil carbon storage capacity in forests and farmland and developing appropriate management techniques
- Carbon storage function through interactions between minerals and organic matter in soil
Ocean circulation structure and material circulation using artificial and natural radioisotopes as tracers
- Evaluation for carbon storage capacity of coastal sediments using radioisotopes
- Food web analysis in freshwater ecosystems using radiocarbon
Environmental dynamics of radionuclides from nuclear facilities
- Developing a highly sensitive analytical method for iodine-129 in environmental samples
- Dynamics of stable and radioactive iodine in marine and inland waters
For other related research, please check JOPSS and researchmap of our group members.
Fukushima Daiichi
Nuclear Power Plant
Accident
We have conducted surveys and research on the radioactive materials released during the Fukushima Daiichi Nuclear Power Plant accident. How did the radioactive materials spread into the environment immediately after the accident? And what will become of these radioactive materials in the future? To answer such as questions, we have been working to understand the current state of the radioactive materials resulting from the accident and predict their behavior through surveys of forests, oceans, and rivers, as well as laboratory experiments and computer simulations.
- Time Series Observations in the Coastal Regions off Northern Ibaraki
-Factors Controlling Concentrations of Radiocesium in Seabed Sediment- - Retention of Mobile Radiocesium in Forest Surface Soils
-Quantifying Microbial Uptake and Abiotic Adsorption- - The Migration of Radioactive Iodine in Seawater
-Variation of Iodine-129 Concentration before and after the Accident at the TEPCO’s Fukushima Daiichi NPS- - Tracking Pollutants in the Pacific Ocean
-Drift Simulation of Tsunami Debris due to the Great East Japan Earthquake- - Spatial Variation in Radioactive-Cesium Deposition Caused by Topographical Factors
-Detailed Examination of the Air-Dose Rate in a Mountainous Forest Catchment- - How Long Does Radiocesium Remain in Forest-Surface Litter?
-Radiocesium Transfer from Litter to Mineral Soil in Two Forest Types- - Exploring the Migration of Radionuclides to the Deep Ocean
-Elucidation of Subduction from the Vertical Distribution of Concentration- - Reconstruction of Atmospheric Release and Dispersion of Radioactive Materials by Computer Simulation
-Contribution to the Refinement of Dose Assessment in the Early Stage of the Accident by Improving the Dispersion Calculation Optimization Method-
For other related research, please check JOPSS and researchmap of our group members.
topics on the old website.
Member
Hideyuki Kawamura
Field of expertise
Marine environment simulation, Oceanography
Degree
Doctor of Science
Topics
- Development of the marine radionuclide migration model SEA-GEARN (Japanese only)
- Simulation of ocean diffusion of radioactive materials from the Fukushima nuclear accident (Japanese only)
- Simulation of drifting debris from the Great East Japan Earthquake (Japanese only)
- Development of an emergency marine environment radioactivity assessment system (Japanese only)
- Development of a material circulation prediction model for the Sea of Japan
Hiroaki Terada
Field of expertise
Atmospheric dispersion simulation, Meteorology
Degree
Doctor of Engineering
Topics
- Improvement of the worldwide version of system for prediction of environmental emergency dose Information WSPEEDI (Japanese only)
- Development and application of the atmospheric dispersion database system WSPEEDI-DB (Japanese only)
- Reconstruction of Atmospheric Release and Dispersion of Radioactive Materials by Computer Simulation－Contribution to the Refinement of Dose Assessment in the Early Stage of the Accident by Improving the Dispersion Calculation Optimization Method－
- Improved Capability for Atmospheric Dispersion Simulation－Enhancement of Prediction Performance of WSPEEDI-II for Middle- Range Scale Dispersion using Krypton-85 Measurement Data－
Mariko Andoh
Field of expertise
Environmental radioactivity, Isotope biogeochemistry
Degree
Doctor of Science
Topics
- Research into the behavior of substances in the environment using radiocarbon and stable isotopes
- Spatial Variation in Radioactive-Cesium Deposition Caused by Topographical Factors－Detailed Examination of the Air-Dose Rate in a Mountainous Forest Catchment－
Katsunori Tsuduki
Field of expertise
Computer system administration
Degree
Doctor of Engineering
Topics
- Computer Management
Takashi Suzuki
Field of expertise
Ocean survey, Iodine-129, Accelarator Mass Spectrometry
Degree
Doctor of Science
Topics
- Elucidation of factors affecting the concentration of iodine-129 in seawater discharged from nuclear facilities
- Elucidation of transport for radioactive iodine in the global-scale transport and coastal marine environments
- Development of a highly sensitive analytical method for iodine-129 in environmental samples
Takahiro Nakanishi
Field of expertise
Geochemistry, Environmental radioactivity, Oceanography
Degree
Doctor of Environmental Earth Science
Topics
- Research into the behavior of substances in the environment using radionuclides and stable isotopes
- Research into the environmental behavior of radionuclides originating from the Fukushima Daiichi Nuclear Power Plant accident
Hiromasa Nakayama
Field of expertise
Local scale atmospheric dispersion simulation
Degree
Doctor of Engineering
Topics
- Development of a local area high resolution atmospheric dispersion and dose assessment system
- Radiological and nuclear terrorism
Masakazu Ota
Field of expertise
Material transports in land surface system
Degree
Doctor of Engineering
Topics
- Development of a land surface model
- Model simulation for transports of tritium, carbon-14, radioiodine, and radiocesium in atmosphere-vegetation-soil system
- Carbon cycling in land surface ecosystems (e.g. forests)
Masanao Kadowaki
Field of expertise
Atmospheric dispersion modeling, Atmospheric chemistry
Degree
Doctor of Science
Topics
- Radioactive iodine cycle in the environment using a chemical transport model
- Development of a multi-scale atmospheric dispersion model
Tsubasa Ikenoue
Field of expertise
Environmental Engineering, Hydrology, Simulation of environmental fate
Degree
Doctor of Engineering
Topics
- Prediction of radioactive cesium behavior in land and rivers for 30 years after the TEPCO Fukushima Daiichi Nuclear Power Plant accident
- Evaluation of the impact of radiocesium supply through rivers to coastal waters off Fukushima on radiocesium behavior in seabed sediment
Rongwei Sun
Field of expertise
Environmental chemistry, Inorganic chemistry
Degree
Doctor of Engineering
Topics
- Mineral function in facilitating soil carbon sequestration
Yukiko Abe
Field of expertise
Soil carbon dynamics, Organic matter form
Degree
Doctor of Agriculture
Topics
- Carbon cycle in subsoil of forests
Takuto Sato
Field of expertise
Atmospheric turbulence, Urban weather, Large eddy simulation
Degree
Doctor of Science
Topics
- Development of an LES local area atmospheric turbulence diffusion model
- Construction of a local area detailed atmospheric diffusion assessment framework for immediate response in nuclear emergencies, etc.
Toru Tanimori
Field of expertise
γ-Ray Astrophysics, High energy physics
Degree
Doctor of Science
Topics
- Establishment of a 3D dose diffusion prediction method and development of a method for investigating inside structures using differences in gamma-ray transmittance
Hiroki Sawa
Topics
- Development of the atmospheric dispersion prediction system WSPEEDI
Hiromi Nemoto
Topics
- Development of the atmospheric dispersion prediction system WSPEEDI
Hiroaki Suda
Topics
- Environmental Sample Analysis
Mutsumi Shimizu
Topics
- Environmental Sample Analysis
Misuzu Kaminaga
Topics
- Environmental Sample Analysis
Kikuko Yoshigaki
Topics
- Environmental Sample Analysis
Noriko Ushiyama
Jun Koarashi
Field of expertise
Isotope biogeochemistry, Radioecology
Degree
Doctor of Engineering
Topics
- Terrestrial carbon cycle and its feedback to climate change
- Behavior of radionuclides in the environment
Azusa Nagakubo
Field of expertise
Environmental science simulation
Degree
Doctor of Engineering
Publications
Access・Contact
Japan Atomic Energy Agency
Nuclear Science Research Institute
Nuclear Science and Engineering Center
Research Group for Environmental Science
2-4 Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
Tel: (+81)-29-282-5100