scholarly journals Quantifying shorebird habitat in managed wetlands by modeling shallow water depth dynamics

2018 ◽  
Vol 28 (6) ◽  
pp. 1534-1545 ◽  
Author(s):  
Danica Schaffer-Smith ◽  
Jennifer J. Swenson ◽  
Matthew E. Reiter ◽  
Jennifer E. Isola
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Managed Wetlands ◽  
Shorebird Habitat ◽  
Shallow Water Depth

Stability of offshore structures in shallow water depth

2011 ◽  
Vol 2 (2) ◽  
pp. 320-333
Author(s):  
F. Van den Abeele ◽  
J. Vande Voorde
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Fossil Fuels ◽  
Oil And Gas ◽  
Structural Response ◽  
Offshore Structures ◽  
Exploration And Production ◽  
Subsea Pipelines ◽  
Wave Induced ◽  
Shallow Water Depth

The worldwide demand for energy, and in particular fossil fuels, keeps pushing the boundaries of offshoreengineering. Oil and gas majors are conducting their exploration and production activities in remotelocations and water depths exceeding 3000 meters. Such challenging conditions call for enhancedengineering techniques to cope with the risks of collapse, fatigue and pressure containment.On the other hand, offshore structures in shallow water depth (up to 100 meter) require a different anddedicated approach. Such structures are less prone to unstable collapse, but are often subjected to higherflow velocities, induced by both tides and waves. In this paper, numerical tools and utilities to study thestability of offshore structures in shallow water depth are reviewed, and three case studies are provided.First, the Coupled Eulerian Lagrangian (CEL) approach is demonstrated to combine the effects of fluid flowon the structural response of offshore structures. This approach is used to predict fluid flow aroundsubmersible platforms and jack-up rigs.Then, a Computational Fluid Dynamics (CFD) analysis is performed to calculate the turbulent Von Karmanstreet in the wake of subsea structures. At higher Reynolds numbers, this turbulent flow can give rise tovortex shedding and hence cyclic loading. Fluid structure interaction is applied to investigate the dynamicsof submarine risers, and evaluate the susceptibility of vortex induced vibrations.As a third case study, a hydrodynamic analysis is conducted to assess the combined effects of steadycurrent and oscillatory wave-induced flow on submerged structures. At the end of this paper, such ananalysis is performed to calculate drag, lift and inertia forces on partially buried subsea pipelines.

Polarization lidar for shallow water depth measurement

2010 ◽  
Vol 49 (36) ◽  
pp. 6995 ◽  
Author(s):  
Steven Mitchell ◽  
Jeffrey P. Thayer ◽  
Matthew Hayman
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Depth Measurement ◽  
Shallow Water Depth

scholarly journals Generalized Lyzenga's Predictor of Shallow Water Depth for Multispectral Satellite Imagery

2013 ◽  
Vol 36 (4) ◽  
pp. 365-376 ◽  
Author(s):  
Ariyo Kanno ◽  
Yoji Tanaka ◽  
Akira Kurosawa ◽  
Masahiko Sekine
Keyword(s):  
Shallow Water ◽  
Satellite Imagery ◽  
Water Depth ◽  
Multispectral Satellite Imagery ◽  
Shallow Water Depth

The Effect of Sunglint Correction for Estimating Water Depth Using Rationing, Thresholding, and Mean Value Algorithms

Rekayasa ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 39-48
Author(s):  
Luhur Moekti Prayogo ◽  
Abdul Basith
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Mean Value ◽  
Point Of View ◽  
Water Object ◽  
Depth Data ◽  
Central Java ◽  
Depth Extraction ◽  
The Mean ◽  
Shallow Water Depth

Satellite-Derived Bathymetry (SDB) is an alternative for obtaining shallow water depth data. The existence of images with various resolutions, the availability of a complete image band can develop the extraction results. This method is based on the principle of the satellite's visible band to estimate water depth. The mapping of shallow water depth is dependent on water conditions, both its brightness and surface. When the sensor senses a water object, the reflected reflection comes from the surface, and some sensors cannot penetrate the water object. The sun's position and the sensor's point of view when sensing it results in interference from the water surface (Sunglint). The sunglint effect on the image can be reduced by performing RGB band correction with NIR Infrared. This study aims to demonstrate the effect of Sunglint's correction on three SDB approaches, namely Thresholding, Rationing, and Mean Value on Worldview 3 imagery in Karimunjawa Islands, Central Java. This study's results indicate that the Sunglint correction on Worldview 3 imagery affects the depth extraction results. The best results are shown by Sunglint's correction using the Thresholding approach (B2-B7), which produces the best correlation with R2 of 0.7364 and (B7-B2) with R2 = 0.7351. Contrastingly, the lowest correlation was generated using the Mean Value ((B2 + B7) / 2) approach without Sunglint's correction with R2 = 0.4015. So this research proves that the Worldview 3 image with Sunglint correction can provide bathymetry data, especially in shallow waters.

Estimation of Shallow Water Depth Using HJ-1C S-band SAR Data

2015 ◽  
Vol 69 (1) ◽  
pp. 113-126 ◽  
Author(s):  
Xiaolin Bian ◽  
Yun Shao ◽  
Wei Tian ◽  
Chunyan Zhang
Keyword(s):  
Shallow Water ◽  
Water Depth ◽  
Depth Estimation ◽  
Absolute Error ◽  
Fast Fourier Transformation ◽  
Linear Dispersion ◽  
Initial Water ◽  
Sar Data ◽  
Shallow Water Depth ◽  
Water Depths

This paper presents a shallow water depth estimation methodology using S-band Synthetic Aperture Radar (SAR) data from the HJ-1C satellite. It is based on the shoaling and refraction of long surface gravity waves as they propagate shoreward. A two-scale Bragg scattering model is used to describe the imaging process of long waves by SAR. By computing the Fast Fourier Transformation (FFT) for the selected sub image, wavelength and direction of the long wave can be retrieved from the two-dimensional (2D) spectra with wave tracking technology. Shallow water depths are then obtained from the linear dispersion relation with the calculated angular wave frequency obtained from other sources or first guesses of initial water depths or wave periods. Applicability and effectiveness are tested in the near-shore area of the Fujian province, China. Comparison between the derived results and water depths from an Electronic Navigational Chart (ENC) indicates that HJ-1C SAR is capable of higher resolution underwater topography detection, and the methodology can be used for shallow water depth estimation with good accuracy. The average absolute error and average relative error of the estimated results is 0·86 m and 11·05%, respectively.

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