Unraveling bed sediment dynamics and accumulation rates in the Northern Arabian Gulf: a synthesis of modeling, radiometric techniques, and field data

The Northern Arabian/Persian Gulf (NG) experiences complex sedimentary dynamics influenced by aeolian and fluvial inputs under highly variable hydrodynamic conditions. This study integrates numerical modeling (Delft3D-FM), radiometric dating, and field observations to quantify sediment accumulation rates and map cohesive bed sediments. Seasonal simulations for summer and winter reveal distinct sediment accumulation trends, with deposition exceeding 0.9 g/cm 2 /yr in the NG. Model validation against radiometric data shows strong agreement, with minor discrepancies in mid-range deposition zones (e.g., 0.24 vs. 0.48 g/cm 2 /yr). Wind-driven shear stress emerges as a key driver of bed sediments, particularly in winter, when higher variability and stronger bed shear stresses are observed compared to summer. These findings highlight the importance of combining field-based and numerical approaches to improve sediment transport predictions in arid coastal environments. This study provides critical insights for sediment management and coastal resilience, particularly in the context of climate change, which is expected to reshape sediment budgets and pose significant challenges to the stability of coastal ecosystems in the NG.