Estuarine Processes Geomorphic Change

Science Center Objects

Changes to the geomorphic structure of estuaries impact hydrodynamics, ecosystem function, and navigation. We are implementing new methods of observing and modeling these changes using innovative field and computational approaches.

Detecting changes to estuarine geomorphology is challenging due to multiple timescales of forcing and the complexity of estuarine sediment transport. Traditional vessel-based bathymetric mapping is difficult due to shallow depths, while airborne LiDAR can be hampered by low water clarity. Over decadal timescales, repeat surveys using these methods can resolve bathymetric changes. Over shorter event timescales, different methods are necessary, including bed-mounted altimeters, erosion pins, and high-resolution hydrodynamic measurements. While these methods can be spatially limited, they can resolve the centimeter-scale changes that occur in estuaries over tidal-to-annual timescales.

Modeling estuarine geomorphology is fraught with uncertainty due to unknown initial conditions and model limitations. However, applying models under various forcing scenarios can elucidate geomorphic processes and yield clues to the long-term geomorphic trajectory of estuarine features. We are using realistic and idealized model configurations to understand the mechanisms that control geomorphology under past, present, and future conditions.