Presenters-0620: Difference between revisions
From CSDMS
Created page with "{{Presenters temp |CSDMS meeting event title=CSDMS 2023: Patterns and Processes Across Scales |CSDMS meeting event year=2023 |CSDMS meeting presentation type=Invited oral presentation |CSDMS meeting first name=Chris |CSDMS meeting last name=Tasich |CSDMS meeting institute=Vanderbilt University |Country member=United States |CSDMS meeting state= Tennessee |CSDMS meeting email address=chris.tasich@vanderbilt.edu |CSDMS meeting title presentation=Equilibrium elevation of th..." |
m Text replacement - "\|CSDMS meeting youtube views=\{\{(Youtube_[^}]+)\}\}" to "|CSDMS meeting youtube views={{#explode:{{$1}}| |0}} |CSDMS meeting youtube AverageViews={{#explode:{{$1}}| |1}}" |
||
| (4 intermediate revisions by 2 users not shown) | |||
| Line 7: | Line 7: | ||
|CSDMS meeting institute=Vanderbilt University | |CSDMS meeting institute=Vanderbilt University | ||
|Country member=United States | |Country member=United States | ||
|CSDMS meeting state= Tennessee | |CSDMS meeting state=Tennessee | ||
|CSDMS meeting email address=chris.tasich@vanderbilt.edu | |CSDMS meeting email address=chris.tasich@vanderbilt.edu | ||
|CSDMS meeting title presentation=Equilibrium elevation of the lower Ganges-Brahmaputra-Meghna Delta | |CSDMS meeting title presentation=Equilibrium elevation of the lower Ganges-Brahmaputra-Meghna Delta | ||
}} | }} | ||
{{Presenters presentation | {{Presenters presentation | ||
|CSDMS meeting abstract presentation= -- | |CSDMS meeting abstract presentation=The natural elevation of the vast, flat landscape of the lower Ganges-Brahmaputra-Meghna (GBM) remains remarkably stable despite persistent relative sea level rise (rSLR). This stability stems from the tight coupling of the land and tides through a robust negative feedback induced by periodic flooding with sediment-rich water. As water levels increase, the inundation depth and duration also increase resulting in more sediment deposition. This has a stabilizing effect and largely negates the initial increase in water level such that the elevation surface appears unchanged. We refer to this stable elevation as the equilibrium elevation. | ||
Here, we investigate the strength of the inundation feedback and the resulting equilibrium elevation. We identify three main controls on this feedback - (1) annual rate of rSLR, (2) mean tidal range (TR), and (3) mean suspended sediment concentration (SSC). We explore the realistic parameter space of each using a simple, zero-dimensional mass balance model. Specifically, we ask (1) what equilibrium elevations are feasible, (2) how these equilibrium elevations compare to tides (e.g., relative to mean sea level (MSL) or mean high water (MHW)), and (3) how equilibrium elevation impacts the duration (hydroperiod) and intensity (depth) of a typical inundation cycle. Results show an incredibly robust feedback for most conditions with the notable exception of low SSCs (< 0.1 g/L). This low, yet realistic value of SSC represents a tipping point at which the equilibrium elevation drops precipitously. At higher rates of rSLR (> 8mm/yr) and lower TR (< 2 m) the equilibrium elevation results in complete drowning of the platform. | |||
|CSDMS meeting youtube code=47erIE2cYwo | |CSDMS meeting youtube code=47erIE2cYwo | ||
|CSDMS meeting youtube views={{#explode:{{Youtube_47erIE2cYwo}}| |0}} | |||
|CSDMS meeting youtube AverageViews={{#explode:{{Youtube_47erIE2cYwo}}| |1}} | |||
|CSDMS meeting participants=0 | |CSDMS meeting participants=0 | ||
}} | |||
{{Presenters additional material | |||
|Working group member=Marine Working Group, Coastal Working Group | |||
}} | }} | ||
Latest revision as of 16:33, 11 June 2025
CSDMS 2023: Patterns and Processes Across Scales
Equilibrium elevation of the lower Ganges-Brahmaputra-Meghna Delta
Abstract
The natural elevation of the vast, flat landscape of the lower Ganges-Brahmaputra-Meghna (GBM) remains remarkably stable despite persistent relative sea level rise (rSLR). This stability stems from the tight coupling of the land and tides through a robust negative feedback induced by periodic flooding with sediment-rich water. As water levels increase, the inundation depth and duration also increase resulting in more sediment deposition. This has a stabilizing effect and largely negates the initial increase in water level such that the elevation surface appears unchanged. We refer to this stable elevation as the equilibrium elevation.
Please acknowledge the original contributors when you are using this material. If there are any copyright issues, please let us know (CSDMSweb@colorado.edu) and we will respond as soon as possible.
Of interest for:
