Bathymetric Estimation
نویسندگان
چکیده
The surface of the ocean bulges outward and inward reflecting the topography of the ocean floor. A dense mapping of ocean surface topography from declassified Geosat altimeter data (US Navy), ERS-1 altimeter data (European Space Agency), and repeat-track coverage from the Topex/Poseidon altimeter (NASA and CNES) has provided the first view of the ocean floor structures in many remote areas of the Earth. The spatial resolution of the derived gravity field is limited by travel-time noise from ocean waves and can be improved through additional dense measurements. Altimeter-derived gravity can be used to estimate seafloor topography but only over an intermediate wavelength band (200 < λ < 20 km) and only in areas where sediment cover is thin. The longer wavelength variations in depth are constrained by depth soundings collected by research vessels over the past 30 years. Detailed bathymetry is essential for understanding physical oceanography, marine geophysics, and perhaps even biological oceanography. Currents and tides are controlled by the overall shapes of the ocean basins as well as the smaller sharp ocean ridges and seamounts. Because erosion rates are low in the deep oceans, detailed bathymetry reveals the mantle convection patterns, the plate boundaries, the cooling/subsidence of the oceanic lithosphere, the oceanic plateaus, and the distribution of off-ridge volcanoes.
منابع مشابه
Estimation of bathymetric depth and slope from data assimilation of swath altimetry into a hydrodynamic model
[1] The proposed Surface Water and Ocean Topography (SWOT) mission would provide measurements of water surface elevation (WSE) for characterization of storage change and discharge. River channel bathymetry is a significant source of uncertainty in estimating discharge from WSE measurements, however. In this paper, we demonstrate an ensemble-based data assimilation (DA) methodology for estimatin...
متن کاملSensor Fusion of Structure-from-Motion, Bathymetric 3D, and Beacon-Based Navigation Modalities
This paper describes an approach for the fusion of 3D data underwater obtained from multiple sensing modalities. In particular, we examine the combination of imagebased Structure-From-Motion (SFM) data with bathymetric data obtained using pencil-beam underwater sonar, in order to recover the shape of the seabed terrain. We also combine image-based egomotion estimation with acousticbased and ine...
متن کاملError estimation of bathymetric grid models derived from historic and contemporary datasets
متن کامل
Signal Direction - of - Arrival and Amplitude Estimation for Multiple - Row Bathymetric Sidescan
In practical applications with bathymetric sidescan sonars, the multipath reflections and other directional interferences are the key limiting factors for a better performance. This thesis proposes a new scheme to deal with the interferences using a multiple-row bathymetric sidescan sonar. Instead of smoothing the measurements over some time or angle intervals, which was previously widely inves...
متن کاملPreliminary Test of Tide-independent Bathymetric Measurement Based on Gps
A GPS system was designed to carry out so-called ‘tide-independent’ bathymetric measurement, in order to compare with the conventional technique in which the tidal observations are made at tide gauges along the coast. Through the estimation and introduction of attitude parameters and height corrections, both based on the GPS solutions, the tide-independent bathymetric measurement can be impleme...
متن کاملSeafloor Topography Modelling in Northern Adriatic Sea Using Synthetic Aperture Radar
Underwater bottom topography may be visible on Synthetic Aperture Radar (SAR) images through the radar signature of ocean surface currents. Using SAR images and a limited number of echo soundings it is possible to constructs accurate depth maps, greatly reducing the costs of bathymetric surveying. Based on shallow water bathymetry synthetic aperture radar (SAR) imaging mechanism and the microwa...
متن کامل