Improved Bathymetric Dataset and Tidal Model for the Northern Bay of Bengal

Krien, Yann; Mayet, Clément; Testut, Laurent; Durand, Fabien; Tazkia, Abdur Rahman; Islam, Akm Saiful; Gopalakrishna, V. V.; Becker, Mélanie; Calmant, Stéphane; Shum, C. K.; Khan, Zillur; Papa, Fabrice; Ballu, Valérie

doi:10.1080/01490419.2016.1227405

Cited by 33 publications

(59 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This modeling framework solves the 3D shallow-water equations for ocean flow and sea level, using finite-element and finite-volume schemes. It has been designed and used for many geographical areas including our region of interest, covering a broad range of spatial scales ranging from ocean basins (e.g., [29,38]) to very shallow lagoons and estuaries (e.g., [39,40]) as well as from short temporal scales (e.g., tsunamis [41]) to seasonal and inter-annual scales (e.g., [42]).…”

Section: Hydrodynamic Tidal Modeling Frameworkmentioning

confidence: 99%

“…The coast of Bengal delta (Figure 1), across Bangladesh and India, is a well-known hotspot of coastal vulnerability. About 150 million people live in this region, characterized by a flat topography, with elevation typically inferior to 4 m above mean sea level (MSL) [29]. The near-shore ocean is characterized by a broad and shallow shelf with a mild slope in the order of 1/1000 to 1/5000, and a macro-tidal regime, with a tidal range in excess of 5 m in the North-Eastern part of the coast.…”

Section: Introductionmentioning

confidence: 99%

“…Inaccurate and outdated representation of the near-shore bathymetry and land topography is identified as one of the most important factors that prevent from accurately reproducing the tidal dynamics, the cyclone surges characteristics as well as the coastal inundation patterns [30,33]. Using a bathymetry dataset derived from a large ensemble of digitized in situ hydrographic surveys, Krien et al [29] significantly improved the representation of tidal hydrodynamics in the Bengal delta region. This dataset, however, essentially consists of point-wise soundings from shipborne surveys, which do not cover the very shallow-water zones (shallower than 2 m below MSL).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

High-Resolution Intertidal Topography from Sentinel-2 Multi-Spectral Imagery: Synergy between Remote Sensing and Numerical Modeling

et al. 2019

View full text Add to dashboard Cite

The intertidal zones are well recognized for their dynamic nature and role in near-shore hydrodynamics. The intertidal topography is poorly mapped worldwide due to the high cost of associated field campaigns. Here we present a combination of remote-sensing and hydrodynamic modeling to overcome the lack of in situ measurements. We derive a digital elevation model (DEM) by linking the corresponding water level to a sample of shorelines at various stages of the tide. Our shoreline detection method is fully automatic and capable of processing high-resolution imagery from state-of-the-art satellite missions, e.g., Sentinel-2. We demonstrate the use of a tidal model to infer the corresponding water level in each shoreline pixel at the sampled timestamp. As a test case, this methodology is applied to the vast coastal region of the Bengal delta and an intertidal DEM at 10 m resolution covering an area of 1134 km 2 is developed from Sentinel-2 imagery. We assessed the quality of the DEM with two independent in situ datasets and conclude that the accuracy of our DEM amounts to about 1.5 m, which is commensurate with the typical error bar of the validation datasets. This DEM can be useful for high-resolution hydrodynamic and wave modeling of the near-shore area. Additionally, being automatic and numerically effective, our methodology is compliant with near-real-time monitoring constraints.

show abstract

Section: Hydrodynamic Tidal Modeling Frameworkmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High-Resolution Intertidal Topography from Sentinel-2 Multi-Spectral Imagery: Synergy between Remote Sensing and Numerical Modeling

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Position of Eocene shelf edge (dashed gray line) and a possible location of thrust front of the fold belt (black barbed line) are adapted from Steckler et al (). Bathymetry data are from Krien, Mayet, et al (). Green points indicate specific sites where subsidence will be displayed as a function of time.…”

Section: Introductionmentioning

confidence: 99%

“…During the Early Holocene, circa 11-7 kyr before present (BP), the sediment discharge was greater by a factor of 2.3, at least, due to the strengthened South Asian monsoon at that time and an abundance of stored hillslope and valley Steckler et al (2008). Bathymetry data are from Krien, Mayet, et al (2016). Green points indicate specific sites where subsidence will be displayed as a function of time.…”

Section: Introductionmentioning

confidence: 99%

Contributions of a Strengthened Early Holocene Monsoon and Sediment Loading to Present‐Day Subsidence of the Ganges‐Brahmaputra Delta

Karpytchev

Ballu

Krien

et al. 2018

Geophysical Research Letters

Self Cite

View full text Add to dashboard Cite

The contribution of subsidence to relative sea level rise in the Ganges‐Brahmaputra delta (GBD) is largely unknown and may considerably enhance exposure of the Bengal Basin populations to sea level rise and storm surges. This paper focuses on estimating the present‐day subsidence induced by Holocene sediment in the Bengal Basin and by oceanic loading due to eustatic sea level rise over the past 18 kyr. Using a viscoelastic Earth model and sediment deposition history based on in situ measurements, results suggest that massive sediment influx initiated in the early Holocene under a strengthened South Asian monsoon may have contributed significantly to the present‐day subsidence of the GBD. We estimate that the Holocene loading generates up to 1.6 mm/yr of the present‐day subsidence along the GBD coast, depending on the rheological model of the Earth. This rate is close to the twentieth century global mean sea level rise (1.1–1.7 mm/yr). Thus, past climate change, by way of enhanced sedimentation, is impacting vulnerability of the GBD populations.

show abstract

Compound simulation of fluvial floods and storm surges in a global coupled river‐coast flood model: Model development and its application to 2007 Cyclone Sidr in Bangladesh

Ikeuchi

Hirabayashi

Yamazaki

et al. 2017

J Adv Model Earth Syst

115

View full text Add to dashboard Cite

Water‐related disasters, such as fluvial floods and cyclonic storm surges, are a major concern in the world's mega‐delta regions. Furthermore, the simultaneous occurrence of extreme discharges from rivers and storm surges could exacerbate flood risk, compared to when they occur separately. Hence, it is of great importance to assess the compound risks of fluvial and coastal floods at a large scale, including mega‐deltas. However, most studies on compound fluvial and coastal flooding have been limited to relatively small scales, and global‐scale or large‐scale studies have not yet addressed both of them. The objectives of this study are twofold: to develop a global coupled river‐coast flood model; and to conduct a simulation of compound fluvial flooding and storm surges in Asian mega‐delta regions. A state‐of‐the‐art global river routing model was modified to represent the influence of dynamic sea surface levels on river discharges and water levels. We conducted the experiments by coupling a river model with a global tide and surge reanalysis data set. Results show that water levels in deltas and estuaries are greatly affected by the interaction between river discharge, ocean tides and storm surges. The effects of storm surges on fluvial flooding are further examined from a regional perspective, focusing on the case of Cyclone Sidr in the Ganges‐Brahmaputra‐Meghna Delta in 2007. Modeled results demonstrate that a >3 m storm surge propagated more than 200 km inland along rivers. We show that the performance of global river routing models can be improved by including sea level dynamics.

show abstract

Improved Bathymetric Dataset and Tidal Model for the Northern Bay of Bengal

Cited by 33 publications

References 38 publications

High-Resolution Intertidal Topography from Sentinel-2 Multi-Spectral Imagery: Synergy between Remote Sensing and Numerical Modeling

High-Resolution Intertidal Topography from Sentinel-2 Multi-Spectral Imagery: Synergy between Remote Sensing and Numerical Modeling

Contributions of a Strengthened Early Holocene Monsoon and Sediment Loading to Present‐Day Subsidence of the Ganges‐Brahmaputra Delta

Compound simulation of fluvial floods and storm surges in a global coupled river‐coast flood model: Model development and its application to 2007 Cyclone Sidr in Bangladesh

Contact Info

Product

Resources

About