jgfs_wave_init.ecf (GFS v17)

Branch / tenant: dev/gfs.v17 (gw_v17) Path: ecf/scripts/gfs/init/wave/jgfs_wave_init.ecf Analysis date: 2026-06-11 Method: AWS Bedrock AgentCore agentcore-mcp-rag MCP cross-checked against the on-disk v17 worktree.

---

Summary

jgfs_wave_init.ecf is the NCO production ecFlow task that initializes the WaveWatch III model for the GFS forecast by generating grid definition files (mod_def.*), bottom boundary conditions, and other static inputs required by the coupled forecast. It calls JGLOBAL_WAVE_INIT, which drives exglobal_wave_init.sh.

---

1. The script itself

Section	Detail
PBS resources	1 node, 128 cpus, 4 GB, 10-min wall, shared
Modules	load_modules.sh ufswm (UFS Weather Model — WW3 tools)
J-Job	JGLOBAL_WAVE_INIT
Rocoto breadcrumb	waveinit.sh

---

2. Execution chain

jgfs_wave_init.ecf
  +-- JGLOBAL_WAVE_INIT
       +-- exglobal_wave_init.sh
            +-- ww3_grid (generate mod_def files per grid)
            +-- ww3_bounc / ww3_prep (boundary/forcing prep)
            +-- cfp (parallel grid generation)

---

3. What the J-Job produces

Product	Description	Location
mod_def.* files	WW3 grid definition files for each wave grid	${COMOUT_WAVE_INIT}/
Bottom boundary files	Bathymetry/bottom conditions	${COMOUT_WAVE_INIT}/
Mask files	Land/sea masks per grid	${COMOUT_WAVE_INIT}/

---

4. Key environment variables

Variable	Meaning
COMOUT_WAVE_INIT	Output: wave initialization files
wavempexec	MPI execution command for WW3 tools
wave_mpmd	MPMD execution tool (cfp)
ENSMEM	Supports ensemble members (shared J-Job)

Configuration

Sources jjob_header.sh -e "waveinit" -c "base wave waveinit".

---

5. v17-specific notes

• UFS Weather Model modules (not ufsda) — WW3 grid tools are model components.
• Shared J-Job: supports GFS, GDAS, and EnKF members via ENSMEM conditional.
• Pre-forecast task: must complete before jgfs_fcst can run with wave coupling.
• 128 cpus, 4 GB — parallel grid generation is CPU-bound.
• 10-min walltime — grid generation is fast for pre-computed grids.

---

6. Change-impact snapshot

Symbol	Risk	Notes
JGLOBAL_WAVE_INIT	MEDIUM	Prerequisite for coupled forecast wave component
exglobal_wave_init.sh	MEDIUM	Shared across GFS/GDAS/EnKF

---

Sources

• On-disk v17 worktree: ecf/scripts/gfs/init/wave/jgfs_wave_init.ecf, dev/jobs/JGLOBAL_WAVE_INIT.
• MCP (tenant gw_v17): on-disk analysis.