Analysis of hydrodynamic patterns in the coastal waters of the Caspian Sea using field measurements

نوع مقاله : Special Issue: New Approaches to Water and Soil Management and Modeling

نویسندگان

1 Assistant Professor, Faculty of Environmental and Marine Sciences, University of Mazandaran, Mazandaran, Iran

2 Associate Professor of Physical Oceanography, Faculty of Environmental and Marine Sciences, University of Mazandaran, Mazandaran, Iran

3 MSc. in Physical Oceanography, Port and Maritime Organization, Tehran, Iran

چکیده

This study investigates the wave and current dynamics of the Caspian Sea, the world’s largest enclosed inland water body, with a focus on its southern coast. The Caspian’s meridional axis, diverse climatic conditions, and complex coastal morphology contribute to highly variable hydrodynamic behavior, yet oceanographic data in the region remain scarce. To address this gap, wave and current measurements were conducted over more than a year at seven nearshore stations—five at 10 meters and two at 30 meters depth—spanning east to west along Iran’s coastline. Data were collected using Acoustic Doppler Current Profilers (ADCP), including AWAC and AquaDopp systems, configured for high-resolution profiling of surface and bottom layers. All measurements underwent multi-layered quality control using PMODynamics software, and descriptive statistical indicators such as mean, maximum, variance, and standard deviation were calculated to assess seasonal and spatial variability. The results confirmed the Caspian Sea’s counterclockwise circulation, with eastward currents prevailing in central and eastern stations (Noshahr, Anzali, Amirabad), and southward flows dominating western stations (Astara). Roudsar showed localized eddy activity, reversing the dominant flow. Seasonal analysis revealed that winter produced the most intense hydrodynamic conditions, with surface current speeds reaching up to 1.15 m/s at Amirabad and standard deviations peaking at 0.16 m/s in autumn. Bottom currents remained more stable, with mean speeds below 0.13 m/s and minimal variance. Wave conditions also varied significantly across stations and seasons. Anzali recorded the most intense wave regime, with significant wave heights frequently ranging between 0.8 and 1.2 meters, especially during autumn and winter. In contrast, spring exhibited the lowest variability, with standard deviations under 0.35 meters at most stations. These patterns reflect the influence of seasonal wind forcing and coastal morphology on wave behavior. These findings provide essential baseline data for coastal management, sediment transport modeling, and infrastructure design in a region increasingly affected by climate change and water level fluctuations

کلیدواژه‌ها

موضوعات


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