Estuarine tidal range dynamics under rising sea levels
Danial Khojasteh1, Shengyang Chen1, Stefan Felder1
1Water Research Laboratory, School of Civil and Environmental Engineering, UNSW Sydney, Sydney, NSW, Australia.
Plos One
|September 20, 2021
Summary
Sea level rise generally amplifies tidal range in most estuaries, but can attenuate it in short, shallow systems. Understanding these sea level rise impacts on tidal dynamics is crucial for estuarine management.
Area of Science:
- Coastal processes
- Oceanography
- Environmental science
Background:
- Estuarine response to sea level rise (SLR) is complex, influenced by energy drivers, geometry, and fluid properties.
- Previous studies on altered tidal ranges under SLR are often site-specific, limiting broader applicability.
Purpose of the Study:
- To systematically understand how tidal range dynamics change in different estuary types under various SLR and river inflow scenarios.
- To provide a generalized understanding beyond site-specific case studies.
Main Methods:
- Development and analysis of a large ensemble of estuarine hydrodynamic models (>1800 simulations).
- Simulation of various sea level rise and river inflow conditions across different estuary types.
Main Results:
- Sea level rise typically amplifies tidal range in most estuaries.
- Exceptions include short estuaries with low-mouth tidal ranges, where SLR attenuates tides.
- SLR shifts locations of minimum tidal range and alters overall tidal range patterns, with greater variations in converging, shallower, or high-inflow systems.
Conclusions:
- Estuary type significantly influences tidal range response to sea level rise.
- Findings offer insights for estuarine managers and decision-makers regarding SLR impacts.
- The study provides a systematic framework for assessing estuarine vulnerability to changing sea levels.
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