A computationally efficient relocatable system for generalized inverse (GI) modeling of barotropic ocean tides is described. The GI penalty functional is minimized using a representer method, which requires repeated solution of the forward and adjoint linearized shallow water equations (SWEs). To make representer computations efficient, the SWEs are solved in...
The application of a generalized inverse approach for assimilating vessel-mounted acoustic Doppler current profiler (VM-ADCP) data into numerical solutions of barotropic tides is described. The derived estimates of tidal currents can be used to detide the VM-ADCP data and expose underlying mean circulation. The methodology is illustrated with data assimilation...
The generalized inverse of a regional model is used to estimate barotropic tidal dissipation along the Hawaiian Ridge. The model, based on the linear shallow-water equations, incorporates parameterizations for the dissipation of energy via friction in the bottom boundary layer and form drag due to internal waves generated at topographic...
The small S₁ ocean tide is caused primarily by diurnal atmospheric pressure loading. Its excitation is therefore unlike any other diurnal tide; in particular, pressure loading is maximum near the equator where the diurnal gravitational potential is zero. The global character of the S₁ tide is here determined by numerical...
This article analyzes the barotropic circulation in the Southwestern Atlantic Shelf using
a three-dimensional numerical model forced with winds and tides. South of 40°S, the shelf
circulation is dominated by the propagation of the semidiurnal tides. In this region the
diurnal tides are generally weak, except at the shelf edge...
A high-resolution primitive equation model simulation is used to form an energy budget for the principal semidiurnal tide (M₂) over a region of the Hawaiian Ridge from Niihau to Maui. This region includes the Kaena Ridge, one of the three main internal tide generation sites along the Hawaiian Ridge and...
A linearized baroclinic, spectral-in-time tidal inverse model has been developed for assimilation of surface currents from coast-based high-frequency (HF) radars. Representer functions obtained as a part of the generalized inverse solution show that for superinertial flows information from the surface velocity measurements propagates to depth along wave characteristics, allowing internal...
Tidal phenomena in the Indonesian
seas are among the most complex in the
world. Complicated coastal geometries
with narrow straits and myriad small islands,
rugged bottom topography next to
wide shelves of shallow water, and large
quantities of tidal power input from the
adjoining Indian and Pacific Oceans—all
combine to...
Repeat transects of full-depth density and velocity are used to quantify generation and radiation of the semidiurnal internal tide from Kaena Ridge, Hawaii. A 20-km-long transect was sampled every 3 h using expendable current profilers and the absolute velocity profiler. Phase and amplitude of the baroclinic velocity, pressure, and vertical...
Observations of turbulence, internal waves, and subinertial flow were made over a steep, corrugated continental slope off Virginia during May–June 1998. At semidiurnal frequencies, a convergence of low-mode, onshore energy flux is approximately balanced by a divergence of high-wavenumber offshore energy flux. This conversion occurs in a region where the...
New empirical estimates of the long-period fortnightly (Mf) tide obtained from TOPEX/Poseidon (T/P) altimeter
data confirm significant basin-scale deviations from equilibrium. Elevations in the low-latitude Pacific
have reduced amplitude and lag those in the Atlantic by 308 or more. These interbasin amplitude and phase
variations are robust features that are...
The most accurate determinations of the global ocean tides are currently based on altimeter measurements made by the Topex/Poseidon satellite. The error spectrum corresponding to the M₂ tidal solution is here estimated, primarily by inverse methods and secondarily by simple differencing in flatter than tidal signal spectrum, and it exceeds...
A hydrodynamic model incorporating a self‐consistent treatment of ocean self‐attraction and loading (SAL), and a physically based parameterization of internal tide (IT) drag, is used to assess how accurately barotropic tides can be modeled without benefit of data, and to explore tidal energetics in the last glacial maximum (LGM). M2...
We assimilate localized mass anomalies inferred from
GRACE ranging measurements into a hydrodynamic model
to improve tidal solutions around Antarctica for the M2, S2,
and O1 constituents. The variational approach used accounts
for the spatial averaging of tidal elevations implicit in the
mass anomaly parametrization used for the GRACE tidal...
Full-depth velocity and density profiles taken along the 3000-m isobath characterize the semidiurnal
internal tide and bottom-intensified turbulence along the Hawaiian Ridge. Observations reveal baroclinic
energy fluxes of 21 ± 5 kW m⁻¹ radiating from French Frigate Shoals, 17 ± 2.5 kW m⁻¹ from Kauai
Channel west of Oahu, and...
We give a detailed description of the semidiurnal-band current and temperature
variability observed during the Internal Waves on the Continental Margin (IWAVES) field
experiments of 1996 and 1997 off of Mission Beach, California. This variability was
dominated by the internal tide, and the structure of the internal tide on the...
Present methods used to retrieve altimeter data do not provide reliable estimates of
sea surface height (SSH) in the nearshore region, resulting in a measurement gap of
25–50 km next to the coast. In the present work, gridded SSH fields produced by
Archiving, Validation, and Interpretation of Satellite Oceanographic data...
Observations from the Coastal Mixing and Optics experiment moored array, deployed
from August 1996 through June 1997, are used to describe barotropic and baroclinic
tidal variability over the New England shelf. The dominant M₂ tidal elevations decrease
toward the northeast to a minimum over the Nantucket shoals (about 34 cm),...
During March–April 1999, 2 weeks of undulating CTD and shipboard acoustic
Doppler current profiler surveys revealed the variability of the intense internal tide on the
northern edge of Georges Bank. The nature of the internal tide was modulated by episodic
surface intrusions of cool, fresh Scotian Shelf Water (SSW), stratifying...
Measurements of tidal currents on the central Oregon shelf are available from several sources, including recent high frequency (HF) coastal radar and Acoustic Doppler Profiler (ADP) deployments, and historical current moorings. In this paper we use a generalized inverse (GI) approach to compare these data to, and then assimilate them...