Sun et al. (2026) Sensitivity of the 2023 Asian Summer Monsoon Water Vapor Transport to Arabian Sea Surface Temperature Anomalies

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Journal of Geophysical Research Atmospheres
• Year: 2026
• Date: 2026-04-06
• Authors: Rui Sun, Aneesh C. Subramanian, Brandon O. Wolding, Tien‐Yiao Hsu, Matthew R. Mazloff, Bruce D. Cornuelle, Janet Sprintall, Arthur J. Miller, Ganesh Gopalakrishnan, Prajeesh Ag, Ibrahim Hoteit
• DOI: 10.1029/2025jd044185

Research Groups

Not explicitly mentioned in the abstract.

Short Summary

This study investigates the impact of the Arabian Sea mini warm pool (ASMWP) sea surface temperature (SST) decline rate on South Asian monsoon precipitation using an SST sensitivity experiment with the WRF model. It found that a slower-than-normal SST decline significantly increases precipitation around the ASMWP while decreasing it elsewhere, driven by changes in water vapor (evaporation, advection) and wind (pressure adjustment, convergence), ultimately enhancing convection through buoyancy changes.

Objective

• To understand the role of the Arabian Sea mini warm pool (ASMWP) warming phase and its subsequent SST decline in the evolution of the South Asian monsoon, specifically focusing on precipitation patterns.

Study Configuration

• Spatial Scale: Regional, encompassing the Arabian Sea, the Arabian Sea mini warm pool (ASMWP), the northern Arabian Sea, and the western coast of India.
• Temporal Scale: Pre-monsoon and monsoon period, with a case study focusing on the 2023 monsoon season.

Methodology and Data

• Models used: Weather Research and Forecasting (WRF) atmospheric model.
• Data sources: SST sensitivity experiment using modified sea surface temperatures (SSTs) as input to the WRF model, based on observed characteristics of the 2023 monsoon.

Main Results

• A slower-than-normal decline in ASMWP SST leads to an increase in off-shore precipitation by more than 100% around the ASMWP.
• Concurrently, this slower SST decline results in a decrease in precipitation in the northern Arabian Sea and along the western coast of India.
• Changes in both water vapor and wind components of the integrated vapor transport (IVT) contribute to the observed precipitation differences.
• Water vapor changes are attributed to: (a) stronger evaporation and precipitation within the ASMWP, and (b) moisture advection outside the ASMWP.
• Wind speed changes are explained by a pressure adjustment mechanism: warmer SST conditions cause atmospheric pressure to drop, leading to wind convergence and creating a weak cyclonic wind anomaly that redistributes water vapor.
• Vertically integrated buoyancy analysis in the ASMWP shows that temperature changes increase buoyancy below 850 hPa (85 kPa), while humidity changes contribute to significantly larger increases in buoyancy between 800 hPa (80 kPa) and 600 hPa (60 kPa), enhancing convection and leading to more precipitation.

Contributions

• Quantifies the significant impact of the rate of SST decline in the ASMWP on regional precipitation patterns during the South Asian monsoon.
• Provides a detailed mechanistic understanding of how ASMWP SST changes influence monsoon precipitation, separating the roles of water vapor (evaporation, advection) and wind (pressure adjustment, convergence).
• Highlights the specific contributions of temperature and humidity changes to atmospheric buoyancy and enhanced convection in the ASMWP.
• Utilizes a sensitivity experiment with a high-resolution atmospheric model to explore hypothetical scenarios relevant to monsoon variability.

Funding

Not explicitly mentioned in the abstract.

Citation

@article{Sun2026Sensitivity,
  author = {Sun, Rui and Subramanian, Aneesh C. and Wolding, Brandon O. and Hsu, Tien‐Yiao and Mazloff, Matthew R. and Cornuelle, Bruce D. and Sprintall, Janet and Miller, Arthur J. and Gopalakrishnan, Ganesh and Ag, Prajeesh and Hoteit, Ibrahim},
  title = {Sensitivity of the 2023 Asian Summer Monsoon Water Vapor Transport to Arabian Sea Surface Temperature Anomalies},
  journal = {Journal of Geophysical Research Atmospheres},
  year = {2026},
  doi = {10.1029/2025jd044185},
  url = {https://doi.org/10.1029/2025jd044185}
}