Project: Couple the pop2 ocean model with CCSM3 and add CCSM pop features
         to LANL pop2

Goal:
  Make the transition to a pop2-based model in CCSM
 
Motivation:  
  LANL has turned its development efforts to pop2 and is
  no longer supporting pop1.4.3, upon which the CCSM3 pop
  is based.  To facilitate our further collaborations with
  LANL and to take advantage of the new features in pop2, 
  the OWG has made the transition to pop2 in CCSM a high
  priority
 
Authority:
  Bill Large, OWG Co-chair
 
Project Lead:   
  Nancy Norton, software engineering
 
Project Support:
  Gokhan Danabasoglu, science
  Keith Lindsay, science

Plan:          
   I) Analysis:
        * Analyze changes to pop2 structure and function
        * Identify modifications required for technical
             compatibility with CCSM (input, output, filenames,
             coupling, diagnostics)
        * Identify essential elements required for side-by-side pop and
          pop2 science comparison runs:
             o cpl6 interface
             o chlorophyll
             o extra tracer support in scripts and code (ideal age)
             o "partial coupling" forcing option
             o marginal-seas balancing
             o correct handling of ice and snow in forcing coupled
   II) Development:
        * CCSM shared constants
        * CCSM technical compatibility (as identified above)
        * CCSM build procedure/script modifications
        * CCSM "essentials"
        * CCSM ocean-model diagnostics (time-averaged and transport
           diagnostics)
  III) Testing:
        * Comparison against CCSM3 pop1.4.3-based solutions
        * Performance evaluation
        
Completion Criteria:
    
    The first phase of this project will be completed when the ccsm pop
    scientific elements which have been identified as essential for
    side-by-side pop/pop2 scientific comparisons have been implemented and
    reviewed.
 

Start Date:  January 2005  (shared development time with hycom project until
                            mid April, 2005)
 
Status:      
   I) Analysis:
        * Analyze changes to pop2 structure and function -- in progress
        * Identify modifications required for technical
             compatibility with CCSM (input, output, filenames,
             coupling, diagnostics)                      -- in progress
        * Identify essential elements required for side-by-side pop and
          pop2 science comparison runs -- done
             o cpl6 interface
             o chlorophyll
             o extra tracer support in scripts and code (ideal age)
             o "partial coupling" forcing option
             o marginal-seas balancing
             o ice_formation
             o correct handling of ice and snow in forcing coupled
   II) Development:
        * CCSM shared constants   -- done
        * CCSM technical compatibility  -- done
        * CCSM build procedure/script modifications  -- done
        * CCSM "essentials"
             o cpl6 interface -- done
             o chlorophyll    -- done
             o extra tracer support in scripts and code (ideal age)  -- done
             o "partial coupling" forcing option  -- done
             o marginal-seas balancing --  done
             o ice_formation           --  done
             o correct handling of ice and snow in forcing coupled  -- done
        * CCSM ocean-model diagnostics (time-averaged and transport
           diagnostics) -- tbd
  III) Testing:
        * Exact restart with Ideal Age -- done
        * Comparison against CCSM3 pop1.4.3-based solutions
             o one-month side-by-side comparison -- in progress
        * Performance evaluation
             o preliminary comparison done
        
Estimated Completion Date (Phase I, "essentials"): 1 June 2005