Long-term investigation of morphodynamic variations of a tidal inlet by remote sensing: A case study of the Meidani Inlet, Hormozgan, Iran

Abstract

Barrier-island inlets are among the most common inlets worldwide. The variation of the inlets, different sediment bypassing mechanisms, and lack of data are some issues for using numerical modeling in all cases. Remote sensing techniques are helpful for analytical investigation and making time series of the study area for categorizing the inlets and defining the morphological processes. The current study employs a feasible method for investigating tidal inlets, evaluates the morphodynamic changes, and applies the method to the Meidani Inlet in Iran. In this study, Landsat images from 1972 to 2019 were acquired and corrected to investigate changes in the ebb-tidal delta by employing the shoreline determination method, performing bathymetry in shallow areas, evaluating the extracted profiles in specific locations within the ebb-tidal delta, and comparing the Landsat image series at various times (change detection). In order to illustrate the morphological changes during the study period, a conceptual model was proposed. The conceptual model presents three reiterated actions of the ebb-tidal delta that varied from 15–25 years due to different environmental conditions. Regional waves, tidal, and wind data were analyzed in detail using Landsat image intervals to investigate the effects of factors causing changes and instability in the cyclic morphodynamic behavior of the Meidani Inlet and characterize the region’s environmental behavior pattern. By employing the method mentioned above, preparing a temporal inlet channel profile and sedimentation trend in the ebb-tidal delta, the Meidani Inlet is determined to be a mixed-energy inlet and a possibility of long-term behavior is predicted. Eastward main inlet channel and the whole ebb-tidal delta migration is the strongest possibility based on the remote sensing investigation over the investigated period.