Gandham et al. (2025) The emerging contribution of Tigris Euphrates basin dust emissions to extreme dust activity over the Arabian Peninsula

Identification

• Journal: Scientific Reports
• Year: 2025
• Date: 2025-12-12
• Authors: Harikishan Gandham, Rama Krishna Karumuri, Hari Prasad Dasari, P. Gopinathan, Thang M. Luong, Ibrahim Hoteit
• DOI: 10.1038/s41598-025-31244-2

Research Groups

• Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
• Climate Change Center, National Center for Meteorology, Jeddah, Saudi Arabia

Short Summary

This study quantitatively assesses, for the first time, the influence of dust emissions from the Tigris–Euphrates river basin (TE) on extreme dust activity over the Arabian Peninsula (AP) using a regionally tuned WRF-Chem model, demonstrating that suppressing TE emissions significantly reduces extreme dust events by over 50% and alters regional dust event distributions and radiative balance.

Objective

• To quantify the influence of dust emissions from the Tigris–Euphrates river basin (TE) on the intensity and frequency of extreme dust activity over the Arabian Peninsula (AP).

Study Configuration

• Spatial Scale: Arabian Peninsula region (20° − 70° E and 0° − 40° N) at a horizontal resolution of 10 km × 10 km, with 50 vertical levels extending up to 1000 Pa.
• Temporal Scale: Three extreme dust seasons (March–August) in 2009, 2011, and 2012.

Methodology and Data

• Models used: Weather Research and Forecasting model coupled with chemistry (WRF-Chem V4.2.1) with the GOCART simple aerosol scheme. The tuning constant C in the dust emission equation was set to 0.5 × 10⁻⁹ kg s² m⁻⁵.
• Data sources: ERA5 global atmospheric reanalysis data (0.25° spatial resolution) for initial and boundary meteorological conditions; MODIS-derived Dust Optical Depth (DOD) dataset for model validation.

Main Results

• Excluding Tigris–Euphrates (TE) emissions significantly reduces mean atmospheric dust loading and decreases dust concentrations across atmospheric layers over the Arabian Peninsula (AP), with the most substantial decreases observed over the Kingdom of Saudi Arabia (KSA) and the Arabian Gulf.
• This reduction enhances surface shortwave radiation, with positive anomalies exceeding 800 W/m² (representing nearly a 10% rise) over the TE and Arabian Gulf regions, thereby increasing solar energy potential.
• It also contributes to cooler nighttime temperatures, with reductions up to -1 °C recorded during summer over the eastern AP, by limiting the trapping of longwave radiation.
• Suppressing TE dust emissions leads to a substantial reduction of over 50% in the occurrence of extreme dust events (DOD ≥ 1) across the central AP and Arabian Gulf during summer months, reaching up to 100% closer to the TE source.
• Conversely, it increases the prevalence of moderate (0.25 ≤ DOD < 0.5) and heavy (0.5 ≤ DOD < 1) dust events across most of the region, particularly over central KSA and the Red Sea (heavy) and Arabian Gulf (moderate).
• Peak PM10 levels in Dust-CTRL simulations reached nearly 1.5 × 10⁻³ kg/m³, while Dust-NR simulations showed significant reductions, with negative anomalies exceeding -0.5 × 10⁻³ kg/m³ over eastern AP and the Arabian Gulf.

Contributions

• Provides the first quantitative evaluation of the impact of dust emissions from the Tigris–Euphrates river basin (TE) on extreme dust activity over the Arabian Peninsula (AP) using a regionally tuned, high-resolution WRF-Chem model.
• Offers a source-isolated, physically consistent quantification of the TE influence on AP dust dynamics, extending beyond previous observational and trajectory-based studies.
• Quantifies the impact of a remote source (TE) on dust extremes in the Kingdom of Saudi Arabia (KSA), providing a robust basis for targeted control measures and informing regional strategies for dust storm mitigation, renewable energy planning, and climate adaptation.

Funding

• Climate Change Centre at KAUST, an initiative of the National Center for Meteorology (NCM), Kingdom of Saudi Arabia (Ref No: RGC/03/4829–01-01).

Citation

@article{Gandham2025emerging,
  author = {Gandham, Harikishan and Karumuri, Rama Krishna and Dasari, Hari Prasad and Gopinathan, P. and Luong, Thang M. and Hoteit, Ibrahim},
  title = {The emerging contribution of Tigris Euphrates basin dust emissions to extreme dust activity over the Arabian Peninsula},
  journal = {Scientific Reports},
  year = {2025},
  doi = {10.1038/s41598-025-31244-2},
  url = {https://doi.org/10.1038/s41598-025-31244-2}
}