jgfs_marine_anlvar.ecf (GFS v17)

Branch / tenant: dev/gfs.v17 (gw_v17) Path: ecf/scripts/gfs/analysis/marine/jgfs_marine_analvar.ecf Analysis date: 2026-06-11

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Summary

jgfs_marine_anlvar.ecf runs the marine variational analysis solver — the core SOCA 3DVar/4DEnVar minimization that assimilates ocean/ice observations to produce the ocean and sea-ice analysis. This is the computational heart of the marine DA system. It calls JGLOBAL_MARINE_ANALYSIS_VARIATIONAL.

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1. Resources & Configuration

Field	Value
PBS resources	8 nodes, 64 cpus/node = 512 MPI ranks, 500 GB/node, exclusive host, 30-min wall
Modules	load_modules.sh ufsda (JEDI/SOCA)
J-Job	JGLOBAL_MARINE_ANALYSIS_VARIATIONAL
Rocoto	marineanlvar.sh

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2. Execution chain

jgfs_marine_analvar.ecf → JGLOBAL_MARINE_ANALYSIS_VARIATIONAL
  → exglobal_marine_analysis_variational.py
    → SOCA variational solver (3DVar/4DEnVar)
    → Assimilates SST, SLA, T/S profiles, sea ice, etc.
    → Produces ocean/ice analysis increments

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3. v17-specific notes

• Heavy resources: 8 nodes x 64 cpus = 512 ranks, 500 GB/node. One of the most resource-intensive DA tasks.
• Exclusive host — needs full node memory for ocean state.
• Part of marine DA chain: anl_init → bmat_init → bmat → anlvar → anlfinal → anlchkpt.
• CRITICAL: produces the ocean/ice analysis that feeds the coupled forecast.
• Python-based SOCA variational solver via pygfs.

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Sources

• On-disk v17: ecf/scripts/gfs/analysis/marine/jgfs_marine_analvar.ecf.