Morphodynamic changes in the Yangtze Estuary under the impact of the Three Gorges Dam, estuarine engineering interventions and climate-induced sea level rise

Cheng, H. Q.; Chen, W.; Li, J. F.; Jiang, Y. H.; Hu, X.; Zhang, X. L.; Zhou, F. N.; Hu, F. X.; Stive, M.J.F.

doi:10.1016/j.epsl.2022.117385

Morphodynamic changes in the Yangtze Estuary under the impact of the Three Gorges Dam, estuarine engineering interventions and climate-induced sea level rise

Title

Morphodynamic changes in the Yangtze Estuary under the impact of the Three Gorges Dam, estuarine engineering interventions and climate-induced sea level rise

Author

Cheng, H. Q. (East China Normal University; Institute of Eco-Chongming (IEC))
Chen, W. (Helmholtz-Zentrum Geesthacht - Zentrum für Material- und Küstenforschung GmbH)
Li, J. F. (East China Normal University; Institute of Eco-Chongming (IEC))
Jiang, Y. H. (China Geological Survey)
Hu, X. (Shanghai Chengtou Group Corporation)
Zhang, X. L. (Shanghai Municipal Planning and Natural Resources Bureau)
Zhou, F. N. (Changjiang Water Resources Commission)
Hu, F. X. (East China Normal University)
Stive, M.J.F. (TU Delft Coastal Engineering)

Date

2022

Abstract

The estuarine turbidity maximum (ETM) in the Yangtze Estuary Delta (YED) is muddy by definition and lacks bottom undulations. However, since 2013, a remarkable change has occurred in the YED. Recent images detected by a multibeam echosounder system, SeaBat 7125, for the first time have confirmed widespread regions of subaqueous dunes in the Yangtze ETM channel. This abnormal change is the result of morphodynamic transformation from the combination of an abrupt decline in sediment supply resulting from the construction of the Three Gorges Dam (TGD) and hydrodynamic changes caused by sea level rise. The latter includes anthropogenic-induced sea level rises (from land subsidence and coastal engineering) of 7–37 cm and a climate-induced sea level rise of 8 cm during the past four decades. Obvious evidence of hydrodynamic changes includes tidal amplification, i.e., a 10–28 cm rise in the tidal range, 42–65 cm rise in the lowest tidal level in the dry season, 45–67 cm rise in the highest tidal level in the flood season and 10–30% increase in the amplitude of the major tidal component. These findings will likely have global implications in formulating strategies to combat the superimposed effects of human interventions and climate change on upstream river and downstream coastal developments.

Subject

estuarine turbidity maxima
sea level rise
subaqueous dunes
tidal amplification
Yangtze Estuary

To reference this document use:

http://resolver.tudelft.nl/uuid:01128df0-d17b-4182-939f-893ebf6b6555

DOI

https://doi.org/10.1016/j.epsl.2022.117385

ISSN

0012-821X

Source

Earth and Planetary Science Letters, 580

Part of collection

Institutional Repository