The Poseidon Ocean Model is a generalized coordinate ocean circulation model

Features of Poseidon:

• Non-Boussinesq dynamics
• Finite Volume numerics
• Arbitrary orthogonal curviliear horizontal coordinates
  • Murray tripole option (coming)
• Generalized vertical coordinates
• Quasi-Isopycnal/Pressure hybrid
• Mixed Layer/Buffer Zone/Isopycnal hybrid
• B- or C- grid. (Run-time configuration)
• Reduced gravity or full barotropic (Run-time option)
• Split-explicit barotropic treatment (Hallberg, 1997)
• ALE technique for splitting horizontal and vertical coordinates
• Implicit vertical diffusion
• Fortran-95 modularized
• Uses GEMS parallelization libraries and message-passing paradigm for efficient execution on a variety of platforms:
• Linux 1cpu (NAG f95)
• Mac OSX (NAG f95 or IBM XLF8.1)
• IBM SP cluster (NCAR blackforest and bluesky)
• Compaq Alpha (GSFC halem)
• SGI Altix 3700 (GMU SCS)
• Vector-invariant formulation with 2nd or 4th order advection of potential vorticity
• Jacobian form for pressure term (Lin, 1997)
• KPP-like or bulk turbulent mixed layers
• Run-time selectable tracer advection schemes
  • 2nd, 3rd or 4th order advection
• Arbitrary bottom topography
  • Minimum ocean depth of millimeters
  • No smoothing required
• Any number of passive tracers
• Variable short wave optical properties
• Compile-time selection of equations of state
• UNESCO
• Wright
• Linear
• Quadratic
• Roll-your-own
• Smagorinsky Laplacian or Biharmonic viscosity (Griffies-Hallberg, 2000)
• Shapiro filter for mass, momentum or tracers
• (Mass filter generates horizontal mass fluxes as bolus fluxes)
• Shapiro filter for null mode removal on B-grid
• Open upper boundary conditions.