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ROMS Development and Operational Forecast

• 1. Development of a Multi-Level Parallel Adaptive ROMS

– John Lou, Yi Chao, Zhijin (Gene) Li (all at JPL)

• 2. ROMS and “Grid” Computing

– Xiaochun Wang, Alex Li, Yi Chao, Peggy Li (all at JPL)

• 3. Development of a Real-Time Operational Forecasting System using ROMS

– Yi Chao, Zhijin (Gene) Li, Peggy Li, Jei-Kook Choi, Xiaochun Wang, Alex Li (All at JPL)

– Jim McWilliams, Patrick Marchesiello, Xavier Capet (UCLA)

– Fei Chai (Univ. of Maine), Dick Barber (Duke Univ.), Francisco Chavez (MBARI)

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1. Development of a Multi-Level Parallel Adaptive ROMS

• PARAMESH (Parallel Adaptive Mesh Refinement) is a package of Fortran 90 subroutines designed to provide an application developer with an easy route to extend an existing serial code which uses a logically cartesian structured mesh into a parallel code with adaptive mesh refinement (AMR).http://esdcd.gsfc.nasa.gov/rib/repositories/inhouse_gsfc/Users_manual/amr.html

• Pyramid (Parallel Unstructured Adaptive Mesh Refinement Library) is a software library for performing parallel adaptive mesh refinement (AMR) on unstructured meshes. http://www-hpc.jpl.nasa.gov/APPS/AMR/

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Application Examples of PARAMESH: 3D AMR

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A Multi-Level Adaptive Grid for ROMS

US WestCoast

OpenOceanB.C.

Open Ocean B.C.

Open Ocean B.C.

• Adaptive refinement on longitude-latitude planes of a 3D ocean grid

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Timelines of a Multi-level Program (1-D)

Level one

Level two

Level three

Information exchange across grid levels

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The Computational Flow of Adaptive ROMS

Multi-level block-structured grid generation (load-balancing)

Read input fields to coarse grid

Interpolate input fields from coarse grid blocks through

the grid tree to all refined levels

Set parameters for multi-level grid(grid scale, land masks, time steps.)

All-level guard cell exchanges ready for time-stepping

2D time-stepping onbocks at all levels

3D time-stepping on grid blocks at all levels

• For each time step of outer time-stepping loop:• Perform Ni time steps of 3D updates at grid level i

•For each 3D update• Perform M steps of 2D updates• Same-level guard-cell exchanges for each 2D update

•Same-level guard cell exchanges foreach 3D update

•All-level guard cell exchanges for all relevant variables

• For each time step of outer time-stepping loop:• Perform Ni time steps of 3D updates at grid level i

•For each 3D update• Perform M steps of 2D updates• Same-level guard-cell exchanges for each 2D update

•Same-level guard cell exchanges foreach 3D update

•All-level guard cell exchanges for all relevant variables

All-level guard cell exchangesfor relevant fields

Update of open boundary condition

Increment global dt

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2. ROMS & “Grid” Computing

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Pacific, US West Coast, & California ROMS

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3. ROMS Real-Time Operational Forecasting

JPLData Server

AncillaryData

DataRetrieval &Processing

ROMS (L1, L2L3, 3-L nested)

COAMPS Data Server

MBARI AOSNData Server

OurOceanLAS

DAS

SGI Computer

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3-level nested coastal ROMS: 15/5/1.5 km

ROMS Configurations

Pacific basin-scale ROMS(providing boundary conditions for the regional ROMS)

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Update of Real-Time Wind ForcingAug. 4, 2003

25-km blended COAMPS/QuikSCAT analysis

3-km COAMPS analysis, Aug. 4

3-km COAMPS forecast, Aug. 5

3-km COAMPS forecast, Aug.6

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Real-Time Stand-alone ROMS without DASAug. 4, 2003

L1 ROMS (15-km) L2 ROMS Coupled Phys-Bio (5-km)

(http://ourocean.jpl.nasa.gov)

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Real-Time L3 ROMS-DASAug. 5 (24 hours forecast from 08/04)

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Real-Time L3 ROMS-DASAug. 6 (48 hours forecast from 08/04)

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AOSN (Adaptive Ocean Sampling Network): Monterey Bay August 2003 Experiment

Integrated Ocean Observing and Prediction Systems