1. No category

Global risk model for the atmospheric
dispersion of radionuclides by nuclear power
plant accidents
T. Christoudias 1 , Y. Proestos 1 , J. Lelieveld
1,2
(1) The Cyprus Institute, Nicosia, Cyprus
(2) Max Planck Institute for Chemistry, Mainz, Germany
Cyprus Institute
christoudias@cyi.ac.cy
1st International Confernence on Nuclear Risks
Outline
1
2
3
4
NPP Global Atmospheric Risk
Model Simulations
Model Validation: Fukushima NPP Accident
Emissions
Risk Assessment
Global Surface Level Concentration
Risk Seasonal Variability
Ground Deposition
Relative Population Risk
5
Uncertainty Estimates
6
Outlook
T. Christoudias (CyI)
NPP Risk Analysis
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NPP Global Atmospheric Risk
Estimate global risk from atmospheric dispersion of
radionuclides from nuclear power plant (NPP) accidents
Risk Assessment Model: Relative, Climatological - no
assumption on time of accident and emission profile:
•
•
•
•
•
Use global atmospheric model (EMAC: ECHAM5/MESSy)
Emission and transport of aerosol and gas radionucludes
Constant continuous emissions from each NPP (1000 hPa)
Removal through decay (gas), dry & wet deposition (aerosol)
Relative Risk estimate: Normalized Climatic average of surface
concentrations, cumulative ground depositions
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NPP Risk Analysis
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Model simulation
20 yr run (2010–2030) for climatic representability:
• Model boundary conditions (SST) from IPCC A2 scenario
• Concentrate on two radio-isotopes with adverse effects:
• Caesium
•
•
•
Cs:
Water-soluble aerosol
Long decay half-life (30 yrs) – no simulated decay
Removed predominantly through precipitation and 5-10%
dry deposition & sedimentation
• Iodine
•
•
137
131
I:
Modeled purely in the gas phase
Atmospheric removal through exponential decay (half-life
8 days)
T. Christoudias (CyI)
NPP Risk Analysis
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Model Validation: Fukushima Accident
•
•
•
•
•
Model setup validated for Fukushima NPP accident
Simulated of
137
Cs,
131
I,
133
Xe transport, decay & deposition
Emission profiles by i) Stohl et al., ii) JAEA
Meteorology driven by ECMWF ERA-Interim reanalysis
Model validated against CTBTO global station measurements
T. Christoudias (CyI)
NPP Risk Analysis
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Nuclear Power Plants Emission Sources
189 Operating (OP) 16 Under Construction (UC) 36 Planned (PL)
Source: World Nuclear Association (WNA), 2014
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Surface Level Concentration
131
Mean 20-yr surface-level concentration of gaseous
I
131
I
Risk highest in US mid-west, east, Japan continental Europe,
maximum in southwestern Germany
T. Christoudias (CyI)
NPP Risk Analysis
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Risk Seasonal Variability
DJF
MAM
JJA
SON
Increased surface concentration risk in Northern Hemisphere winter
T. Christoudias (CyI)
NPP Risk Analysis
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Ground Deposition
137
Cs
Climatological total global cumulative dry and wet deposition &
sedimentation of aerosol 137 Cs
Enhanced risk over tropics: wet deposition due to heavy precipitation
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NPP Risk Analysis
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National Risk Distribution
Nuclear policy making at the national level: Provide risk
estimates for all NPP opearated/planned by each country/nation
Data for all countries available online
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NPP Risk Analysis
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Relative Risk by Country
Relative Risk Index (RRI) = Relative Concentration/Deposition
× Population Exposed
400
Relative Risk Index
350
Ground deposition
Inhalation
300
250
200
150
100
50
US
IN
FR
DE
JP
CN
PK
CH
TW
GB
ES
RU
KR
BE
UA
SK
CZ
IR
MX
CA
NL
HU
SI
SE
BR
BG
AM
RO
FI
AR
ZA
1
NPP(OP)
Highest risk index globally by USA, followed by India and France
T. Christoudias (CyI)
NPP Risk Analysis
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Relative Risk Planned & Proposed NPP
Under Construction NPP
Relative Risk Index
250
Proposed NPP
250
Ground deposition
Inhalation
200
Relative Risk Index
300
200
150
100
Ground deposition
Inhalation
150
100
50
50
1
1
IN
CN
VN
US
JO
NPP(PL)
TR
IR
RU
SK
EG
UA
BY
LT
FI
ZA
CN
IN
TW
AE
RU
JP
NPP(UC)
Future risk index to become highest in China, followed by India and
the USA.
T. Christoudias (CyI)
NPP Risk Analysis
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Statistical Uncertainty
Operating
Planned
Under Construction
Coefficient of variation (σ/µ):
• Overall within 5%
• Does not exceed 20% locally
Temporal variability appropriately
captured
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Outlook
Refinements underway:
• Runs at higher resolution (120→50 km) for impacts
• Ensemble of IPCC scenarios for systematic uncertainty range
Future Outlook:
• Data available for interfacing with impacts studies (e.g.
human health)
• Per country itemized risk analysis possibility available
• Model available and open for collaborations on NPP risk
assessment
• Global Climatological Risk Assessment approach
complementary to regional/scenario specific studies
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NPP Risk Analysis
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References
T Christoudias, Y Proestos, J Lelieveld
Atmospheric Dispersion of Radioactivity from Nuclear Power
Plant Accidents: Global Assessment and Case Study for the
Eastern Mediterranean and Middle East
Energies 7 (12), 8338-8354
T Christoudias, Y Proestos, J Lelieveld
Global risk from the atmospheric dispersion of radionuclides by
nuclear power plant accidents in the coming decades
Atmospheric Chemistry and Physics 14 (9), 4607-4616
T Christoudias, J Lelieveld
Modelling the global atmospheric transport and deposition of
radionuclides from the Fukushima Dai-ichi nuclear accident
Atmospheric Chemistry and Physics 13 (3), 1425-1438
T. Christoudias (CyI)
NPP Risk Analysis
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