Modeling Puget Sound Circulation Mitsuhiro Kawase School of Oceanography PRISM Retreat, 2002

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Modeling Puget Sound CirculationMitsuhiro
KawaseSchool of OceanographyPRISM Retreat, 2002
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National Ocean Partnership ProgramA Partnership
for Modeling the Marine Environment of Puget
Sound, WashingtonONR Award N000140210503Mitsuhir
o Kawase, Allan Devol, Miles Logsdon and Mark
Warner, School of OceanographyWilliam Winn,
College of EducationUniversity of Washington,
Seattle, WAFY 02 Funding 390,924

• Objectives
• Develop, maintain and operate a system of
  simulation models of Puget Sounds circulation
  and ecosystem, a data management system for
  oceanographic data and model results, and an
  effective delivery interface for the model
  results and observational data for research,
  education and policy formulation.
• Develop fundamental understanding of the Sounds
  working, and address questions raised by the
  regional community concerning management of the
  Sound and its resources.
• Partners
• Department of Natural Resources, King County,
  Washington (R. Shuman, B. Nairn)
• Department of Ecology, State of Washington (J.
  Newton)
• Puget Sound Naval Shipyard (S. Swanson, R.
  Johnston)
• Ocean Inquiry Project (F. Stahr, C. Sarason)

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Puget Sound Circulation Model

• Support from National Oceanographic Partnership
  Program (NOPP), FY 2002 - 2008
• In collaboration with King County DNR
• Based on Princeton Ocean Model (POM) code
• 360x540m resolution,14 vertical levels
• Predicted variables Velocity, temperature,
  salinity, turbulent kinetic energy, turbulent
  master length

Model domain and bathymetry
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Puget Sound Circulation Model (Contd)

• Hindcasting Year 2000 (with Bruce Nairn, KC-DNR)
• Accurate time-average exchange circulation in the
  Main Basin
• Accurate time-average recirculation around Vashon
  Island (northward current 30cm/s in Colvos
  Passage)
• Excessive transport into the deep Whidbey Basin
  (20) - dynamics of the Skagit Delta, Deception
  Pass transport?

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Puget Sound Circulation ModelTasks FY 2002

• Complete coupling with the MM5 weather prediction
  model
• Routine hindcasting of Puget Sound circulation
• Dynamics of Carr Inlet
• Generate Lagrangian trajectories for study of
  planktonic genetic diversity (diatoms, geoducks)

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Variability at Seasonal/Interannual Time Scales

• Historical data analysis
• Simple model of Puget Sound circulation for
  quantitative sensitivity study

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Schematic of exchange circulation in a fjord
(cross-section)
River Input (Fresh, Light)
Outflow
Tidal Mixing
Sharp Pycnocline
Main Basin
Marine influence (Salty, Dense)
Inflow/Reflux
Entrance Sill
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• Terrestrial Influence River Runoff
• Maximum in Winter/Spring
• Marine Influence Coastal Upwelling
• Maximum in Spring/Summer

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T/S Seasonal Cycle in Puget Sound Main Basin
(1992)
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A Box Model of Puget Sound CirculationAmanda
Babson, M.S. Thesis

• Twelve boxes to represent Puget Sound (six
  regions, upper and lower layer)
• Predicts salinity in each box, advective fluxes
  between boxes and mixing between upper and lower
  boxes
• Forced by river discharge and external salinity
  in deep Admiralty Inlet
• Conservation of mass and salt, simple
  parameterization of momentum and vorticity
  balance, and stratification-dependent vertical
  mixing

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Salinity in a Box Model of Puget Sound
Circulation (Babson, 2002)
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Seasonal Transport in the Box Model (positive
out)
Outflow at Surface
Inflow at Depth
Jan
Apr
Jul
Oct
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Potential Temperature 1999
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Salinity Anomaly, Puget Sound Main Basin at 100m
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R0.6 (36 of variance)
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Salinity and Potential Density in Central Puget
Sound, 1990 - 1998(Blue 100m Red 200m)
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Salinity 1992-1999 in the Box Model
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Temperature Anomaly, Puget Sound Main Basin at
100m
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R0.57 (33 of variance)