Zheng et al. (2026) Indian Ocean Dipole Impacts on Autumn Heat and Early-Winter Precipitation over the Arabian Peninsula

Identification

• Journal: Journal of Climate
• Year: 2026
• Date: 2026-10-19
• Authors: Yiling Zheng, Hari Prasad Dasari, Dingrui Cao, Raju Attada, Ibrahim Hoteit
• DOI: 10.1175/jcli-d-25-0683.1

Research Groups

• Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
• Climate Change Center, National Center for Meteorology, Jeddah, Saudi Arabia
• Department of Atmospheric and Oceanic Sciences, McGill University, Montréal, Canada
• Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research Mohali, Punjab, India

Short Summary

This study investigates the season-spanning influence of the Indian Ocean Dipole (IOD) on autumn heat and early-winter precipitation over the Arabian Peninsula, revealing distinct mechanisms for warming and precipitation amplification during positive IOD events and suppressed precipitation during negative IOD.

Objective

• To clarify the Indian Ocean Dipole's (IOD) role in Arabian Peninsula (AP) climate variability by examining its influence on autumn (September–November, SON) heat and early-winter (October–December, OND) precipitation.
• To provide a physical basis for assessing compound heat-rainfall hazards in a warming world.

Study Configuration

• Spatial Scale: Arabian Peninsula (AP), southern AP, northern AP, southwestern coast, northeast AP.
• Temporal Scale: Autumn (September–November, SON), early-winter (October–December, OND), seasonal mean shifts, synoptic timescales.

Methodology and Data

• Models used: Not specified in the provided text.
• Data sources: Not specified in the provided text.

Main Results

• During positive IOD, the southern Arabian Peninsula experiences warming in autumn (SON) via a radiative pathway, driven by anomalous low-level moisture transport enhancing the greenhouse effect, strengthening downward longwave radiation, and increasing diabatic heating.
• Positive IOD amplifies early-winter (OND) precipitation through two mechanisms: a low-level moisture conveyor leading to convergence-dominated precipitation along the southwestern coast, and a strengthened subtropical jet interacting with the moistening environment in the northeast.
• Negative IOD features weaker, spatially distinct autumn (SON) cooling centered over the northern Arabian Peninsula, primarily from cold-air advection, and broadly suppressed early-winter (OND) precipitation.
• On synoptic timescales, enhanced moisture during positive IOD can first radiatively amplify heatwaves and then fuel extreme precipitation within days, indicating a dual fingerprint.

Contributions

• Clarifies the Indian Ocean Dipole's (IOD) role in Arabian Peninsula (AP) climate variability.
• Provides a physical basis for assessing compound heat-rainfall hazards in a warming world.
• Identifies distinct mechanisms for IOD's influence on autumn heat and early-winter precipitation.

Funding

Not specified in the provided text.

Citation

@article{Zheng2026Indian,
  author = {Zheng, Yiling and Dasari, Hari Prasad and Cao, Dingrui and Attada, Raju and Hoteit, Ibrahim},
  title = {Indian Ocean Dipole Impacts on Autumn Heat and Early-Winter Precipitation over the Arabian Peninsula},
  journal = {Journal of Climate},
  year = {2026},
  doi = {10.1175/jcli-d-25-0683.1},
  url = {https://doi.org/10.1175/jcli-d-25-0683.1}
}