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Jagüey -1 well site. North Coast of Cuba in Block 27, ~16 NM from Cuba, ~28 NM to US federal waters, and ~80 NM from the Florida Keys Water depth ~5900 feet Based on well drilled in 2004, no gas, H 2 S, or hydrates are expected and lighter end oil (30 API) is anticipated - PowerPoint PPT Presentation
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Jagüey-1 well site• North Coast of Cuba
in Block 27, ~16 NM from Cuba, ~28 NM to US federal waters, and ~80 NM from the Florida Keys
• Water depth ~5900 feet
• Based on well drilled in 2004, no gas, H2S, or hydrates are expected and lighter end oil (30 API) is anticipated
• For 30 API, 16 K barrels a day production expected
Transport pathways in the Florida Straits
• Within the Florida Straits a strong ocean current flows toward the east from the Gulf of Mexico
• The Florida Current is the beginning of the Gulf Stream which flows north along the US East Coast
• On the average, the inner edge of the Gulf Stream is within 10 miles of Miami and Ft. Lauderdale, FL, and at times there can be >3 knot flow within a few miles of the coast
• Due to fast surface currents in the Florida Current/Gulf Stream, strong onshore winds would be required for shoreline impacts to Florida
http://oceancurrents.rsmas.miami.edu/atlantic/florida.html
Statistical modeling – MMS (2002)
• Trajectories from instantaneous releases from 3 locations along Cuba coast
• Less than 0.5% probability of shoreline impacts along U.S. coast within 3 days; ~10-20% within 10 days
• Segments 19-26 (top right panel) have 0.5-9% probability of impacts within 10 days
Statistical modeling – ASA (2010)
• Scenarios:– Large/small diesel
spills (873/349 tons) during Mar-Oct and Oct-Mar
• Two hundred 14-day scenarios (from instantaneous releases) run using six years of modeled currents/winds
• Calculate probabilities of oil on water surface, shoreline oiling, and minimum travel time
• ~10-20% of trajectories impact Florida
Worst case scenario defined as the scenario leading to the shortest time to shoreline impact
– First impacts in Florida Keys in 6-9 days
Oil trajectory Probability of shoreline oiling
• In the event of an actual spill, NOAA OR&R would use real-time observations and models to forecast oil movement
• Necessary components for oil trajectory forecasting– Surface oil observations, ocean current forecasts, wind forecasts– Method of determining uncertainty
Surface Oil Observations
• Satellite detection of oil came of age during Deepwater Horizon spill
• Detection algorithms applied across all available imagery
• E.g. during DWH spill, some potential slicks were detected off Cuba
– Analysis of currents suggested source in Yucatan Straits rather than DWH
• Was not confirmed to be oil on subsequent overflights
– overflights with trained observers still critical to providing accurate estimation of surface oil distribution
Ocean Current Forecasts
• NOAA OR&R has access to output from multiple operational models (~10) that cover Florida Straits– NAVO/NRL (NCOM, NCOM-AMSEAS,
HYCOM, HYCOM-GOM, IASNFS)– NOAA (NGOM, RTOFS)– Academic (SABGOM)
• Models assimilate satellite observations improving accuracy of representing Loop Current, Florida Current, Gulf Stream
• Numerous models allow an ensemble approach similar to that used during Deepwater Horizon
http://www7320.nrlssc.navy.mil/IASNFS_WWW/
Wind forecasts• In addition to ocean currents,
wind forecasts are critical to predicting movement of oil
• Winds at well site are most frequently NE or NNE
• Numerous met buoys provide real-time wind measurements
• For forecasts we use NWS gridded forecasts and spot forecasts
• NOAA Tropical Prediction Center covers Cuban waters
Additional Real-time observations
• HF radar off SE Florida• Surface drifters• NAVO ocean features analysis for
Gulf Stream position – gives distance of Florida Current from shoreline
• NOAA/AOML Ocean current analysis
• Satellite derived ocean currents• Satellite derived surface winds
Putting it all together in GNOME (General NOAA Operational Model Environment)
• Surface oil observations are used to initialize oil spill trajectory model
• Trajectories of oil movement are calculated using multiple sources of forecast currents/winds
• Suite of model runs bounds uncertainty in prediction
Final forecast product
• Similar to during DWH, NOAA OR&R would produce at least daily forecasts of surface oil
• First DWH trajectory forecast produced 4/21/2010, ~11 AM CDT
• Forecasts give predicted distribution of oil in 24/48/72 hours and include uncertainty on prediction
Trajectory forecasting for potential future spills
• Forecasts of ocean currents and winds generally have decreasing skill beyond 3 days
• Prediction of where oil might come ashore from future spills or far into the future relies on statistical approach
• Early in DWH, OR&R produced statistical picture of potential impacts should the release continue 90 days into the future
• Results are probabilities of impact and travel times
Individual Scenarios
Parameters for the statistical simulation
• 500 simulations – random start times in April or May, 1992-2007
• 90 day constant rate release• 10,000 particles• “Medium Crude” weathering• 20nm square receptor grid
Travel Time