Longshore sediment transport by large-scale lake circulations at low-energy, non-tidal beaches: A field and model study

Ton, A.M.; Vuik, V.; Aarninkhof, S.G.J.

doi:10.1016/j.coastaleng.2022.104268

Longshore sediment transport by large-scale lake circulations at low-energy, non-tidal beaches

Title

Longshore sediment transport by large-scale lake circulations at low-energy, non-tidal beaches: A field and model study

Author

Ton, A.M. (TU Delft Coastal Engineering)
Vuik, V. (TU Delft Coastal Engineering; HKV Consultants)
Aarninkhof, S.G.J. (TU Delft Hydraulic Engineering)

Department

Hydraulic Engineering

Date

2023

Abstract

Low-energy, non-tidal lake beaches are known to be subject to longshore morphodynamics, but little is known about how they are driven by wind and wave-driven currents. Lake Markermeer is a shallow (∼4 m deep), wind-dominated lake, of approximately 700 km². A gradient in wind-induced water level set-up at the leeward shore induces a flow from the shallower to the deeper parts of the lake, thereby generating a large-scale, horizontal circulation. Flow measurements and results from a numerical Delft3D model of the lake show that these circulations impact the nearshore currents greatly, even more than wave-driven longshore currents for most wind conditions. From nearshore measurements at the first study site in lake Markermeer, we found a clear relation between longshore sediment transport capacity and the measured longshore volume flux. The model numerical can predict flow direction and magnitude for any wind condition. Using wind statistics, the net transport capacity for a short period or a long term mean can be predicted. The relation is confirmed for a second study site, which shows a distinct net transport capacity that could not be explained from wave-driven longshore flow alone. Concluding, large-scale lake circulations are of great significance for the morphological development of low-energy, non-tidal beaches in shallow, wind-driven water bodies. Knowledge of these circulations and their dependence on wind characteristics is a crucial factor to better understand and predict sediment losses of lake beaches.

Subject

Delft3D
Large-scale lake circulation
Longshore transport
Low-energy
Morphodynamics
Sandy lake beach

To reference this document use:

http://resolver.tudelft.nl/uuid:94788d89-8472-4a0f-ae4c-3d459d2b0bcd

DOI

https://doi.org/10.1016/j.coastaleng.2022.104268

ISSN

0378-3839

Source

Coastal Engineering, 180

Part of collection

Institutional Repository