Alone et al. (2026) Seasonal forecasts of marine heat waves using Monsoon Mission Climate ForecaSt system

Identification

• Journal: Theoretical and Applied Climatology
• Year: 2026
• Date: 2026-04-10
• Authors: Ashish Alone, Akhil Srivastava, Suryachandra A. Rao, Maheswar Pradhan, Geetanjali Masamaddi S, Aarti Soni, Sudheer Joseph
• DOI: 10.1007/s00704-026-06218-7

Research Groups

• Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
• Indian National Centre for Ocean Information Services, Ministry of Earth Sciences, Hyderabad, India

Short Summary

This study evaluates the seasonal prediction skill of marine heatwaves (MHWs) in the Indian Ocean and surrounding basins using the Monsoon Mission Coupled Forecast System version 1 (MMCFSv1). It finds that the system demonstrates good forecast skill in key regions and seasons, with ensemble-based thresholds effectively capturing MHW variability.

Objective

• To evaluate the seasonal prediction skill of marine heatwaves (MHWs) in the Indian Ocean and surrounding basins using the Monsoon Mission Coupled Forecast System version 1 (MMCFSv1).

Study Configuration

• Spatial Scale: Indian Ocean and surrounding basins, specifically highlighting the Western Arabian Sea, North Bay of Bengal, and North-East Pacific.
• Temporal Scale: Forecast period from 1982 to 2017, focusing on seasonal forecasts, particularly during March-April-May (MAM) and June-July-August (JJA) seasons.

Methodology and Data

• Models used: Monsoon Mission Coupled Forecast System version 1 (MMCFSv1).
• Data sources:
  • Observational data (freely available in the public domain).
  • Model hindcasts (available on request from the authors).
  • MHWs detected using the 90th percentile sea surface temperature (SST) threshold from the full ensemble distribution across model members.
  • Forecast skill assessed using the Pearson correlation coefficient and Mean Squared Skill Score (MSSS).

Main Results

• Seasonal forecasts exhibit good prediction skill for MHWs across key regions, including the Western Arabian Sea, the North Bay of Bengal, and the North-East Pacific.
• The highest forecast skill is observed during the March-April-May (MAM) and June-July-August (JJA) seasons.
• Ensemble-based thresholds are more effective in capturing the spatial and temporal variability of MHWs compared to single-member approaches.
• The highest prediction skill is achieved with initializations in February and March, with a gradual decline in performance for later initialization months.
• The study underscores the critical role of ensemble spread in accurately capturing MHW extremes.

Contributions

• Provides a robust framework for enhancing seasonal MHW forecasts, particularly for the Indian Ocean basin.
• Advances climate-resilient planning and marine hazard mitigation strategies by demonstrating the capability of a coupled forecast system for MHW prediction.
• Highlights the importance of using ensemble-based thresholds and ensemble spread for better capturing MHW variability and extremes.

Funding

• Indian Institute of Tropical Meteorology, Pune
• Ministry of Earth Sciences, Government of India

Citation

@article{Alone2026Seasonal,
  author = {Alone, Ashish and Srivastava, Akhil and Rao, Suryachandra A. and Pradhan, Maheswar and S, Geetanjali Masamaddi and Soni, Aarti and Joseph, Sudheer},
  title = {Seasonal forecasts of marine heat waves using Monsoon Mission Climate ForecaSt system},
  journal = {Theoretical and Applied Climatology},
  year = {2026},
  doi = {10.1007/s00704-026-06218-7},
  url = {https://doi.org/10.1007/s00704-026-06218-7}
}