Overview¶
BMKG previously operated independent atmospheric, wave, and ocean models, which limited the representation of cross-domain interactions in forecast outputs. To address this limitation, BMKG has implemented InaCAWO (Indonesia Coupled Atmosphere–Wave–Ocean), a three-way coupled modelling system built on the COAWST (Coupled-Ocean-Atmosphere-Wave-Sediment Transport) framework.
InaCAWO seamlessly integrates three established models:
| Component | Model | Role |
|---|---|---|
| Atmosphere | WRF | Atmospheric dynamics and surface forcing |
| Ocean | ROMS | Three-dimensional ocean circulation |
| Waves | SWAN | Wind-wave generation and propagation |
The three-way coupling approach, pioneered by Warner et al. (2010), allows direct exchange of critical metocean surface data between models through the Model Coupling Toolkit (MCT). Each component is aware of and responds to the others, much as these processes occur in nature.
Key capabilities¶
- High resolution — uniform 3 km grid covering the Indonesian archipelago (90–145°E, 15°S–15°N)
- Improved coupling — representation of atmosphere–wave–ocean interactions in a single integrated system
- Operational forecasting — four cycles per day (00, 06, 12, 18 UTC) on BMKG HPC
- Extended lead times — 10-day forecasts at 00/12 UTC; 90-hour forecasts at 06/18 UTC
Compared to its predecessors, InaCAWO provides significantly higher spatial resolution, enabling finer-grained simulation of complex air–sea processes and more localized forecasts for severe weather and marine hazards — particularly tropical cyclones affecting southern Indonesian waters.
System context¶
InaCAWO is the coupled forecast component of the BMKG Maritime Meteorological System (MMS1). It receives global model data as initial and boundary conditions, runs on the BMKG HPC under the Baron ROME (Real-Time Operational Modeling Environment) workflow manager, and delivers products to downstream analysis, archiving (MANDALA), and dissemination systems.
Go to the Configurations page for model setup details, or the Operational Flow for the production workflow.
References¶
Source documents in refs/inacawo/:
AGU_InaCAWO_Final_Draft-print.pdf— scientific introductionCAWO_ValidationStudyReport.pdf— one-year validation study (Baron Weather, 2023)OM_InaCAWO_Software-Manual.pdf— system architecture and software manual (Baron Weather, 2024)