Improving the GFDL/URI

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Improving the GFDL/URI Coupled Hurricane-Ocean
Model for Transition to Operations Isaac
Ginis University of Rhode Island
B. Thomas, URI I-J. Moon, URI A. Falkovich, NCEP
M. Bender, GFDL
Support is provided by JHT/USWRP
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GFDL/URI Coupled Model

• Implemented to operations at NCEP in 2001 after
  three years of near-real time testing in
  1998-2000
• Improvements implemented in 2003
• New ocean model domain configurations
• Ocean coupling over entire ocean domains
• Gulf Stream and Loop Current data assimilation

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Examples of the Coupled Model ForecastsHurricane
Isabel Initial Time 00 UTC 15 Sept, 2003
Sea Surface Currents
Sea Surface Temperature
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Ongoing Efforts Toward Future Improvements

• Ocean coupling in the Eastern Pacific basin
• High resolution version of the GFDL model
• Air-sea flux parameterization
• Coupled hurricane-wave-ocean system

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Hurricane IGNACIO 22-27 AUG, 2003
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Hurricane Ignacio GFDL Model Forecast (12Z 24
AUG, 2003)
Red - Operational Green - Coupled Black - Observed
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High-resolution Version of the GFDL/URI Coupled
Model

• Goal To better resolve the hurricane core
  region, especially in major hurricanes
• Grid configuration
• 1/2o (stationary) 1/6o and 1/12o (movable)

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Hurricane Isabel, Sept 8 12Z, 2003
High resolution GFDL model
Operational GFDL model
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3-Nest
2-Nest
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Hurricane Isabel (2003)
kts
High Res GFDL
SHIPS
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Air-Sea Fluxes in High Wind Conditions Behavior
of Cd and Ch in the GFDL model
?
Cd
Ch
Wind Speed (m/s)
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Idealized Sensitivity Experiments
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New Coupled Wind-Wave Model
young waves
mature waves
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WW3
CWW
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Wave Field in a Hurricane
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Operational GFDL Model
Future Coupled Hurricane-Wave-Ocean Model
Atmosphere
Atmosphere
GFDL Hurricane Model
GFDL(WRF) Hurricane Model
Wind Air Temp.
Flux
Wind Air Temp.
Flux
SST
Wave Boundary Model
SST
SST Current
Wave Spectra
Flux
Flux
Currents,
NCEP WAVEWATCH III


POM (HYCOM)
POM
Elevations, SST
Ocean
Ocean
Waves
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Plans for Operational Implemantion

• Ocean coupling in the Eastern Pacific is planned
  for operational implementation in 2004
• The high resolution GFDL coupled model will be
  tested in near real-time in 2004 is planned for
  operational implementation in 2005
• The coupled GFDL hurricane-wave-ocean model is
  being developed