STRADI

Project description

This proposal brings together experts in information theory with experts in atmospheric dispersion modelling, to tackle a particularly difficult and highly relevant scientific problem.

The overall goal of this project is to develop methods for determining the source term of an accidental release of radionuclides or other hazardous substances into the atmosphere which is suitable for both real-time application (e.g., for emergency preparedness) and assessment of environmental damages.

The focus of the project will be on determination of activity of an accidental release of radiation from a nuclear power plant using measurements of gamma doses (or combination of gamma doses and concentrations) but the method will be equally useable for other atmospheric point-source releases, and may also lead to improvements in related fields (e.g., determination of greenhouse gas sources).

In order to achieve this objective, we need to improve the tools used for atmospheric dispersion modelling as well as t he statistical tools used for inverse modelling. All partners of this project have experience with this task and contributed novel ideas in various aspect of this problem in their previous work.

We intend to combine the expertise of NILU in atmospheric modelling with that of UTIA and EPFL in uncertainty modelling and statistical inference. We believe that this unique complementarity will allow us to deliver results that will be useful for a wider class of inverse modelling problems and significantly contribute to the basic results of environmental research.

Since consortium members have already established contacts with national and international radiation protection authorities, the developed methods may be immediately useful and ready for their own applications.

This research is supported by EEA/Norwegian Financial Mechanism under project MSMT-28477/2014

Project partners

---

Project team

---

---

---

Results

Publications

Journal papers

1. Tichý, O., Šmídl, V., Hofman, R., Stohl, A: A Tuning-free Method for the Linear Inverse Problem and its Application to Source Term Determination, Geoscientific Model Development, vol.9, 11 (2016), p. 4297-4311 [Download]
2. Pecha P., Šmídl V.: Inverse modelling for real-time estimation of radiological consequences in the early stage of an accidental radioactivity release, Journal of Environmental Radioactivity, vol.164, 1 (2016), p. 377-394 [Download]
3. Xiong, X. Smidl, V., Filippone, M.: Adaptive Multiple Importance Sampling for Gaussian Processes, Journal of Statistical Computation and Simulation, 87.8 (2017): 1644-1665. [Download]
4. Evangeliou, N., Zibtsev, S., Myroniuk, V., Zhurba, M., Hamburger, T., Stohl, A., Balkanski, Y., Paugam, R., Mousseau, T. A., Møller, A. P., Kireev, S. I.: Resuspension and atmospheric transport of radionuclides due to wildfires near the Chernobyl Nuclear Power Plant in 2015: An impact assessment, Nature Scientific Reports, 6, 26062, doi:10.1038/srep26062.
5. Evangeliou, N., Hamburger, T., Talerko, N., Zibtsev, S., Bondar, Yu., Stohl, A., Balkanski, Y., Mousseau, T. A., Møller, A. P.: Reconstructing the Chernobyl Nuclear Power Plant (CNPP) accident 30 years after. A unique database of air concentration and deposition measurements over Europe, Environmental Pollution ,216, 408-418, doi:10.1016/j.envpol.2016.05.030.
6. Lukáš Adam, Martin Branda: Sparse optimization for inverse problems in atmospheric modelling, Environmental Modelling & Software, vol.79, 3 (2016), p. 256-266. [Download] [Software]

Submitted Journal papers

1. Ulrych, L., Šmídl, V.: Sparse and Smooth Bayesian Linear Regression with Application to ETEX data, Statistical modelling journal
2. Tichý, O., Šmídl, V., Šindelářová, K., Hofman, R., Hýža, M., Stohl, A. : Bayesian inverse modeling and source location of an unintended I-131 release in Europe in the fall of 2011, Atmospheric Chemistry and Physics
3. Ondřej Tichý, Václav Šmídl, Radek Hofman: Bayesian Linear Inverse modelling of multi-nuclide source term from gamma dose rates, Journal of Hazardous Materials
4. Nikolaos Evangeliou, Thomas Hamburger, Anne Cozic, Yves Balkanski, and Andreas Stohl. : Inverse modelling of the Chernobyl source term using atmospheric concentration and deposition measurements, Atmospheric Chemistry and Physics Discussions doi:10.5194/acp-2017-330, in review, 2017.

International conferences

1. Nikolaos Evangeliou, Andreas Stohl, Yves BalkanskiGlobal transport of Fukushima-derived radionuclides from Japan to Asia, North America and EuropeEGU General AssemblyEGU2017-6605, 2017, 23-28 April 2017, Vienna, Austria (Invited)
2. Nikolaos Evangeliou, Sergey Zibtsev, Viktor Myroniuk, Marina Zhurba, Thomas Hamburger, Andreas Stohl, Yves Balkanski, Ronan Paugam, Timothy A. Mousseau, Anders P. Møller, Sergey I. Kireevtmospheric transport of radionuclides emitted due to wildfires near the Chernobyl Nuclear Power Plant in 2015EGU General AssemblyVol. 18, EGU2016-6034, 17-22 April 2016, Vienna, Austria.
3. Tichý Ondřej, Šmídl Václav, Hofman Radek Bayesian Estimation of Source Term of Atmospheric Radiation Release with Interval Prior The 8th International Congress on Environmental Modelling and Software (iEMSs), (Toulouse, FR, 10.07.2016-14.07.2016)
4. Ulrych Lukas, Šmídl VaclavBayesian estimation of linear regression model with unknown prior and noise covariance matrixISBA 2016 world meetingSardinia, Italy 13.-17.5.2016
5. Tichý Ondřej, Šmídl Václav Linear Inverse Problem with Range Prior on Correlations and Its Variational Bayes InferenceBayesian Statistics in Action: BAYSM 2016 Bayesian Young Statisticians Meeting 2016, (Florence, IT, 20160619)
6. Belal Alkomiet, Tichy Ondrej , Smidl VaclavBayesian inference for source term determination with unknown covarianceGeophysical Research AbstractsEGU General Assembly 2017, (Vienna, AT, 23.04.2016-28.04.2016)
7. Ondřej Tichý, Václav Šmídl, Radek Hofman: Bayesian estimation of a source term of radiation release with approximately known nuclide ratios, European Geosciences Union General Assembly 2016, Vienna, Austria [Download]
8. Radek Hofman, Ondřej Tichý, Kateřina Šindelářová: Analysis of elevated I-131 samples observed in 2011 over Europe, European Geosciences Union General Assembly 2016, Vienna, Austria [Download]
9. Lukáš Adam, Martin Branda, Thomas Hamburger: Source term identification in atmospheric modelling via sparse optimization, European Geosciences Union General Assembly 2015, Vienna, Austria [Download]
10. Lukáš Adam, Martin Branda: A Comparison of Traditional and New Inverse Modelling Techniques for Source Term Identification in the Atmosphere, European Geosciences Union General Assembly 2015, Vienna, Austria [Download]
11. Václav Šmídl, Radek Hofman: Bayesian Estimation of Prior Variance in Source Term Determination, European Geosciences Union General Assembly 2015, Vienna, Austria [Download]
12. Václav Šmídl, Ondřej Tichý, Radek Hofman: Hierarchical Prior for Source Term Determination and Its Variational Bayes Estimation, CTBT: Science and Technology 2015, Vienna, Austria [Download]
13. Petr Pecha, Emilie Pechová: Pitfalls Associated with the Estimation of Radiological Burdens on Population Caused by Radiation Accidents, MATHMOD 2015 - 8th Vienna International Conference on Mathematical Modelling, Vienna, Austria [Download]

Software and applications

• Lukáš Adam, Martin Branda: Sparse optimization for inverse problems in atmospheric modelling [Download]
• Lukáš Adam: Matlab package for calculation of non-negative least squares with optional LASSO or Tikhonov regularizations [Download]
• Ondřej Tichý: A Tuning-free Method for the Linear Inverse Problem and its Application to Source Term Determination [Download]
• Radek Hofman: quick_look, software for vizualization of Flexpart outputs [Link to repository]
• Radek Hofman: quick_dose, software for calculation of gamma dose rates from Flexpart concentration and deposition fields [Link to repository]

Project publicity and international cooperation

• Project kickoff presentation (20 Oct 2014, UTIA)

  Radek Hofman had a presentation on basics of inverse modeling.
  
  

• Days of Science 2015, UTIA

  Days of Science are organised annually by the Czech Academy of Sciences in order to present latest research results and directions to general public. STRADI team participated in this event and presented project objectives and current progress to a group of interested visitors.
  
  

• Visit at NILU, Norway

  The visit took place between 29 Sep and 1 Oct 2015. NILU partners organized a workshop on the use of atmospheric transport model Flexpart developed there. The course was lead by a professional Flexpart tutor Dr. Delia Arnold from ZAMG, Austria. Among trainees, there were researchers both from NILU and UTIA. During a meeting held after the workshop were defined main research objectives for 2016.
  
       

• Participation at workshop organized by Bundesamt für Strahlenschutz (BfS), Münich, Germany

  The workshop took place on 15 May 2015. It's agenda was focused on inverse modelling in the context of radioactive releases, specifically on novel methods for estimating a source composed of multiple radionuclides using gamma dose rate measurements. STRADI team held a presentation on Bayesian methods developed within the project.
  
  

• Poster at an international conference

  Václav Šmídl, Ondřej Tichý, Radek Hofman: Hierarchical Prior for Source Term Determination and Its Variational Bayes Estimation, CTBT: Science and Technology 2015, Vienna, Austria
  
  

• Poster at an international conference

  Václav Šmídl, Radek Hofman:Bayesian Estimation of Prior Variance in Source Term Determination, European Geosciences Union General Assembly 2015, Vienna, Austria
  
  

• Poster at an international conference

  Lukáš Adam, Martin Branda: A Comparison of Traditional and New Inverse Modelling Techniques for Source Term Identification in the Atmosphere, European Geosciences Union General Assembly 2015, Vienna, Austria
  
  

• Oral presentation at an international conference

  Lukáš Adam, Martin Branda, Thomas Hamburger: Source term identification in atmospheric modelling via sparse optimization, European Geosciences Union General Assembly 2015, Vienna, Austria
  
  

• Presentation of the project at Science Fair 2016

  Ondřej Tichý presented the project and its results at a Science Fair held 19.-21. 5. in Prague.
  
  

• Poster at an international conference

  Radek Hofman, Ondřej Tichý, Kateřina Šindelářová: Analysis of elevated I-131 samples observed in 2011 over Europe, European Geosciences Union General Assembly 2016, Vienna, Austria
  
    

• Poster at an international conference

  Ondřej Tichý, Václav Šmídl, Radek Hofman: Bayesian estimation of a source term of radiation release with approximately known nuclide ratios, European Geosciences Union General Assembly 2016, Vienna, Austria
  
    

• Poster at an international conference

  Lukáš Ulrych, Václav Šmídl: Bayesian estimation of linear regression model with unknown prior and noise covariance matrix, ISBA 2016 World meeting, Sardinia, Italy
  
  

• MŠMT Project handout

  
  

• Presentation at MŠMT conference

  Václav Šmídl, Nikolaos Evangeliou: Source-Term Determination of Radionuclide Releases by Inverse Atmospheric Dispersion Modelling, 2nd Czech-Norwegian Research Conference, 8th November 2016, Prague, Czech Republic