Evolución morfodinámica del delta de Tinajones, río Sinú: una visión estacional e interanual

Here, we analyzed the morphodynamic evolution of the Sinú River delta, also known as Tinajones Delta, on seasonal and interannual time scales from 1984 to 2021. We calculated monthly sediment fluxes transported by waves, tides, and the river to evaluate the relative dominance of these forces in the morphodynamics of the system. We complemented these analyses with a morphometric characterization based on satellite imagery. The Tinajones Delta was classified as a mixed-influence system, where the influence of waves and river discharge alternates seasonally due to the dynamics of the Intertropical Convergence Zone. During the dry season (December-April), the delta is dominated by the action of the waves due to the intensification of the trade winds. In contrast, during the transitional and wet seasons (May-July and August-November), the river dominates the delta due to the increase in rainfall rates and river discharge. A significant trend of decreasing river sediment discharge was evidenced, leading to an increase in wave influence on the system. This behavior was also evidenced in the morphometric evolution analyses, which show a recent predominance of erosion in the central part of the delta, accompanied by accretion in the lateral sectors and the formation of spits, which are typical of wave-dominated coastal environments. This paper highlights the importance of analyzing deltas as dynamic equilibrium systems with variability and trends in the dominant forcing rather than as stationary systems over the mid- and long-term.