sergey m. varlamov
DESCRIPTION
The 3rd International Workshop on Next Generation Climate Models for Advanced High Performance Computing Facilities Tokyo, Japan, March 28 -30, 2001 Performance and Verification of the Oil Spill Modeling System for the Sea of Japan. Sergey M. VARLAMOV - PowerPoint PPT PresentationTRANSCRIPT
The 3rd International Workshop on Next Generation Climate Models for
Advanced High Performance Computing Facilities
Tokyo, Japan, March 28 -30, 2001
Performance and Verification
of the Oil Spill Modeling System
for the Sea of JapanSergey M. VARLAMOV
Institute of Environmental Sciences, RISSHO University
E-mail: [email protected]
Jong-Hwan YOON
Research Institute for Applied Mechanics, Kyushu
University
The risk of environmental disasters related with
the spilling of oil products into the sea forces
the development of the high-quality oil spill
simulation and prediction system. It would be
an important tool for the planning of the spill
protection and spill response operations etc.
Simulation of the oil spreading and fate in the
sea is one of practical applications that
requires and integrates the results of
meteorological, oceanographical and the “oil
spill” modeling communities...
Motivations:
Where will go the oil after it was spilled in to
the sea?
- from the start of incident up to it removing from
the sea due to any processes
What will be the oil state at all stages of spill?
- density (buoyancy)
- viscosity (recovery techniques)
- emulsion state (amount to recover)
- [chemical composition - toxicity] etc.
Most important questions:
Fate of oil spilled at sea• Spreading• Horizontal and vertical transport by wind and
sea currents• Natural dispersion• Buoyancy• Emulsification• Evaporation• Dissolution• Photo-oxidation• Sedimentation and shoreline stranding• Biochemical degradation
Oil spill simulations system (Varlamov et. al., 2000)
Oil spill modelOil spill model**
Spill Transport and Weathering
Particles Tracking Model Graphical analysisGraphical analysis
subsystemsubsystem
Ocean Ocean CirculationCirculation
ModelsModels
Meteorological Meteorological subsystemsubsystem
Oil propertyOil propertydatadata
EnvironmenEnvironmentaltal
datadata
Ocean Ocean currentscurrents
datadata
MeteorologicMeteorologicalal
datadata
Oil spill Oil spill simulationssimulations
Ocean circulation models
• At nowadays the ocean circulation models is a part of system
Reasons: no products similar to meteorological analysisand forecasts, i.e. 3D currents, temperature, salinity, wavesfield are available ...
• OCM’s spatial resolution and model domain defines the scale and applicability area of the oil spill analysis and prediction system
although the simplified version with the local wind drift currents model could be applied for any area covered by meteorological forecasts and with the land-sea mask defined (GTOPO30 for the global version).
Ocean circulation models
3-D primitive equations Modular Ocean Model (GFDL MOM)- 1/6° grid (1218 km horizontal resolution)- 19 vertical levels (step 15 m in upper layers; up to 600 m below
1500 m)- rigid grid approximation
wind drift shear local current model + 2-D shallow water nonlinear model (2.5 dimensional model)
- bi-linear vertical turbulent eddy viscosity profile (Poon & Madsen, 1991)
- variable vertical step (from 1 m in upper sea layer)- 1/12° grid (69 km horizontal resolution)- 16 tidal constituents are used at the open boundaries etc.
Oil spill analysis and prediction system was tested with two types of the Japan Sea ocean circulation models:
Outline of Oil Spill Fate and Trajectory Model (year 2001 version)-1
Particles tracking model:
Spill is presented as an ensemble of particles each characterized by its properties that includes
- position on plane and the depth- diameter- density- viscosity- fraction of water in oil (emulsion)- fraction evaporated- fraction [biochemically] degradated etc.
Outline of Oil Spill Fate and Trajectory Model (year 2001 version)-2
Depending on position, model oil particles are
- transported by wind (at the sea surface)- transported by 3D sea currents- experience buoyancy effect- 3D random diffusion (wind and current dependant)- oil–coastal line interaction- evaporation at the sea surface (Fingas, 1996) - emulsification at the sea surface (Mackay et al, 1980)- biochemical degradation- [oil-sea bottom interaction]
Outline of Oil Spill Fate and Trajectory Model (year 2001 version)-3
Other model properties:
- universal 2D horizontal bicubic spline interpolation from arbitrary meteorological, bottom topography, and ocean circulation model grids (with masking of land surface meteorological data)
- initial droplet diameters distribution in accordance with observed dispersion droplet size distribution (Delvigne and Sweeney, 1988), modified by weathering processes, both “permanent” surface slick and oil dispersed into the water column are simulated
- modification of oil particles density and viscosity as result of emulsification, evaporation and biochemical degradation
- assimilation of observed oil slick position for long-term spill simulation
Technical Characteristics and the Improvement of System Performance Model properties:
- programming languages: C (system routines and meteorological GRIB data decoding software) and FORTRAN-90 (ocean circulation and spill models)
- OpenMP directives are used for the parallelization of ocean circulation and spill physical core modules
- computational effects on the parameterization of physical processes was analyzed and fixed (buoyancy-vertical diffusion-particles diameter-integration time step problem)
Routine oil spill simulation and prediction system parameters
Meteorological analysis and forecasts data are received once a day. Total 3.7 Mb are received, and at 18:00 UTC (local night) it usually takes approximately 7 - 8 minutes
SW OCM is started and run the currents simulation and prediction for 126 h (5 days). With 10s time step it takes 1 h 03 min on 667 MHz Alpha processor (GFDL MOM 1/12° - 25 min)
Oil spill simulation could be run by operator and for 5 days with 10000 droplets it will takeless then 14 min
127 127 128 128 129 129 130 130 131 131 132 132 133 133
33
34
34
35
35
36
36
System Verification: Simulation of the Osung No 3 Oil Spill in the Sea of Japan
Fragment of the Ocean Circulation Model Domain in Tsushima strait area (TerrainBase topography)
Korea
Japan
Hakata
Pusan
Tsushima Isl.
Volume Transport - Camelia Line
Runing average total volume transport through Tsushima strait at the Hakata-Pusan section(‘Camelia’ Line, 03.1997-06.1999 )
3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11
0
2
4
6 Monitoring results (Data of Takikawa & Yoon, 2000)•Total
•Eastern Channel
•Western Channel
127 128 129 130 131 132 133
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Down Left
3.5Sv 3.0 Sv 2.5 Sv 2.0 Sv 1.5 Sv 1.0 Sv
-1.0 Sv 1.580.666
0.920.35
0.230.05
-0.5 Sv
0.0 Sv 2.401.06
1.710.75
1.040.43
0.5 Sv 2.471.10
2.120.94
1.770.79
1.0 Sv 3.251.46
2.541.14
2.190.98
1.840.83
1.500.68
1.5 Sv 2.611.18
2.261.03
1.910.87
Takikawa -original data
Takikawa -after tides
elimination
Model:TerrainBase
Total:mean/stddev
2.253.60
2.481.06
2.504.04
East:mean/stddev
0.891.83
1.040.70
1.101.73
West:mean/stddev
1.362.81
1.440.57
1.401.71
Model simulationswith TerrainBasetopography
Model simulations with smoothed ETOPO5topography(Eastern/Western channel volume transport ~2.2 when ~0.8 expected)
Tidal Sea Level Variations
5 10 15
-100
0
100
5 10 15
-100
0
100
Idzuhara (upper) and Hakata (lower) tidal stations, February 2000Observed (blue, black) and simulated(red) sea level anomalies, cm.
RMS Error = 12 cm
RMS Error = 9 cm
- 229 kl of Bunker C oil spilled
- Largest part of oil was recovered(April 8-9)
- April 9, 1997 15:45 JST coastline ofN.Tsushima Isl. was polluted
Animated Simulation Results:Push on the map to start demonstration, esc to stop it, the label fields pass to the next slide.
Model particles in upper 2 m layer, size by color.Sea current and surface wind drift (4% of wind speed)
Oil spill accident with Korean tanker Osung No 3
Oil concentration in upper 2 m layer
It is strongly related with the model particles size and trace mainly
the surface drifting slick position
Oil concentration in upper 2 m layer
It is strongly related with the model particles size and trace mainly
the surface drifting slick position
Animated Simulation Results:Push on the map to start demonstration, esc to stop it, the label fields pass to the next slide.
Sea current and surface wind drift (4% of wind speed)
Tanker Osung No 3 oil spill incident simulation
Relative mass of oil stranded at the shoreline
Relative mass of oil stranded at the shoreline
Some spill model integral parameters
Mean (volume weighted) diameterof floating model oil particles, m
Mean (volume weighted) diameterof floating model oil particles, m
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4000
6000
8000
10000
Total number of active modeloil particles
Total number of active modeloil particles
4 5 6 7 8 9 10 11 12 13
0
500
1000
1500
4 5 6 7 8 9 10 11 12 13
0
50
100
150
4 5 6 7 8 9 10 11 12 13
0
200000
400000
Mean (volume weighted) dynamicviscosity of floating oil, cP
Mean (volume weighted) dynamicviscosity of floating oil, cP
Conclusion
Oil spill numerical simulation system
could provide important information for
the short term (at least up to 4-5 days)
planning of accidental oil spill recovery
operations