Detection of tidal dissipation in the solid Earth by satellite tracking and altimetry

Nature ◽  
1996 ◽  
Vol 381 (6583) ◽  
pp. 595-597 ◽  
Author(s):  
R. D. Ray ◽  
R. J. Eanes ◽  
B. F. Chao
Keyword(s):  
Solid Earth ◽  
Satellite Tracking ◽  
Tidal Dissipation

Tidal dissipation in the oceans: astronomical, geophysical and oceanographic consequences

1977 ◽  
Vol 287 (1347) ◽  
pp. 545-594 ◽  
Keyword(s):  
Energy Dissipation ◽  
Solid Earth ◽  
Global Ocean ◽  
Ocean Tide ◽  
The Moon ◽  
Tidal Dissipation ◽  
Tidal Forces ◽  
Degree Harmonic ◽  
Tidal Acceleration ◽  
Second Degree

The most precise way of estimating the dissipation of tidal energy in the oceans is by evaluating the rate at which work is done by the tidal forces and this quantity is completely described by the fundamental harmonic in the ocean tide expansion that has the same degree and order as the forcing function. The contribution of all other harmonics to the work integral must vanish. These harmonics have been estimated for the principal M 2 tide using several available numerical models and despite the often significant difference in the detail of the models, in the treatment of the boundary conditions and in the way dissipating forces are introduced, the results for the rate at which energy is dissipated are in good agreement. Equivalent phase lags, representing the global ocean-solid Earth response to the tidal forces and the rates of energy dissipation have been computed for other tidal frequencies, including the atmospheric tide, by using available tide models, age of tide observations and equilibrium theory. Orbits of close Earth satellites are periodically perturbed by the combined solid Earth and ocean tide and the delay of these perturbations compared with the tide potential defines the same terms as enter into the tidal dissipation problem. They provide, therefore, an independent estimate of dissipation. The results agree with the tide calculations and with the astronomical estimates. The satellite results are independent of dissipation in the Moon and a comparison of astronomical, satellite and tidal estimates of dissipation permits a separation of energy sinks in the solid Earth, the Moon and in the oceans. A precise separation is not yet possible since dissipation in the oceans dominates the other two sinks: dissipation occurs almost exclusively in the oceans and neither the solid Earth nor the Moon are important energy sinks. Lower limits to the Q of the solid Earth can be estimated by comparing the satellite results with the ocean calculations and by comparing the astronomical results with the latter. They result in Q > 120. The lunar acceleration n , the Earth’s tidal acceleration O T and the total rate of energy dissipation E estimated by the three methods give astronomical based estimate —1.36 —28±3 —7.2 ± 0.7 4.1±0.4 satellite based estimate —1.03 —24 ±5 — 6.4 ± 1.5 3.6±0.8 numerical tide model — 1.49 —30 ±3 —7.5± 0.8 4.5±0.5 The mean value for O T corresponds to an increase in the length of day of 2.7 ms cy -1 . The non-tidal acceleration of the Earth is (1.8 ± 1.0) 10 -22 s ~2 , resulting in a decrease in the length of day of 0.7 ± 0.4 ms cy -1 and is barely significant. This quantity remains the most unsatisfactory of the accelerations. The nature of the dissipating mechanism remains unclear but whatever it is it must also control the phase of the second degree harmonic in the ocean expansion. It is this harmonic that permits the transfer of angular momentum from the Earth to the Moon but the energy dissipation occurs at frequencies at the other end of the tide’s spatial spectrum. The efficacity of the break-up of the second degree term into the higher modes governs the amount of energy that is eventually dissipated. It appears that the break-up is controlled by global ocean characteristics such as the ocean­-continent geometry and sea floor topography. Friction in a few shallow seas does not appear to be as important as previously thought: New estimates for dissipation in the Bering Sea being almost an order of magnitude smaller than earlier estimates. If bottom friction is important then it must be more uniformly distributed over the world's continental shelves. Likewise, if turbulence provides an important dissipation mechanism it must be fairly uniformly distributed along, for example, coastlines or along continental margins. Such a global distribution of the dissipation makes it improbable that there has been a change in the rate of dissipation during the last few millennium as there is no evidence of changes in ocean volume, or ocean geometry or sea level beyond a few metres. It also suggests that the time scale problem can be resolved if past ocean-continent geometries led to a less efficient breakdown of the second degree harmonic into higher degree harmonics.

scholarly journals Impact of Geophysical Fluids on UT1

2009 ◽  
Vol 5 (H15) ◽  
pp. 213-214
Author(s):  
Richard S. Gross
Keyword(s):  
Solid Earth ◽  
Secular Change ◽  
Length Of Day ◽  
Tidal Dissipation ◽  
The Earth ◽  
Fluid Core ◽  
Period Variations ◽  
Decadal Variations ◽  
Tidal Variations ◽  
Geophysical Fluids

AbstractGeophysical fluids have a major impact on the Earth's rotation. Tidal variations within the oceans are the predominant cause of subdaily length-of-day (lod) variations while those within the solid body of the Earth are a major source of longer period variations; tidal dissipation within the solid Earth and oceans cause a secular change in lod. Fluctuations of the atmospheric winds are the predominant cause of nontidal lod variations on sub-decadal time scales while decadal variations are caused by interactions between the fluid core and mantle.

MSA ROEBLING MEDAL LECTURE: NITROGEN DIFFUSION IN MINERALS, WITH IMPLICATIONS FOR N CYCLING IN THE SOLID EARTH

2018 ◽  
Author(s):  
E. Bruce Watson ◽  
◽  
Daniele J. Cherniak ◽  
Maxwell S. Drexler ◽  
Morgan F. Schaller ◽  
...  
Keyword(s):  
Solid Earth ◽  
N Cycling ◽  
Nitrogen Diffusion

JGR-Solid Earth moves toward electronic communication

Eos ◽  
1994 ◽  
Vol 75 (6) ◽  
pp. 59
Author(s):  
Deborah Gray
Keyword(s):  
Solid Earth ◽  
Electronic Communication

scholarly journals Energetics of the Solid Earth: An integrated perspective

2020 ◽  
Vol 1 (1-2) ◽  
pp. 28-35 ◽  
Author(s):  
Masaki Yoshida ◽  
M. Santosh
Keyword(s):  
Solid Earth

scholarly journals Multi-Channel Singular Spectrum Analysis on Geocenter Motion and Its Precise Prediction

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1403
Author(s):  
Xin Jin ◽  
Xin Liu ◽  
Jinyun Guo ◽  
Yi Shen
Keyword(s):  
Solid Earth ◽  
Spectrum Analysis ◽  
Mean Squared Error ◽  
Moving Average ◽  
Singular Spectrum Analysis ◽  
Singular Spectrum ◽  
Autoregressive Moving Average Model ◽  
Seasonal Characteristics ◽  
Geocenter Motion ◽  
Moving Average Model

Geocenter is the center of the mass of the Earth system including the solid Earth, ocean, and atmosphere. The time-varying characteristics of geocenter motion (GCM) reflect the redistribution of the Earth’s mass and the interaction between solid Earth and mass loading. Multi-channel singular spectrum analysis (MSSA) was introduced to analyze the GCM products determined from satellite laser ranging data released by the Center for Space Research through January 1993 to February 2017 for extracting the periods and the long-term trend of GCM. The results show that the GCM has obvious seasonal characteristics of the annual, semiannual, quasi-0.6-year, and quasi-1.5-year in the X, Y, and Z directions, the annual characteristics make great domination, and its amplitudes are 1.7, 2.8, and 4.4 mm, respectively. It also shows long-period terms of 6.09 years as well as the non-linear trends of 0.05, 0.04, and –0.10 mm/yr in the three directions, respectively. To obtain real-time GCM parameters, the MSSA method combining a linear model (LM) and autoregressive moving average model (ARMA) was applied to predict GCM for 2 years into the future. The precision of predictions made using the proposed model was evaluated by the root mean squared error (RMSE). The results show that the proposed method can effectively predict GCM parameters, and the prediction precision in the three directions is 1.53, 1.08, and 3.46 mm, respectively.

Rapid boron isotope and concentration measurements of silicate geological reference materials dissolved through sodium peroxide sintering

2021 ◽  
Author(s):  
Yue Cai ◽  
Troy E Rasbury ◽  
Kathleen M Wooton ◽  
Xin Jiang ◽  
Di Wang
Keyword(s):  
Solid Earth ◽  
Reference Materials ◽  
Earth Science ◽  
Boron Isotope ◽  
Earth System ◽  
Sodium Peroxide ◽  
Wide Range ◽  
Concentration Measurements

Understanding the movement of fluids in the solid Earth system is crucial for answering a wide range of important questions in Earth Science. Boron (B) is a perfect tracer for...

scholarly journals Autumn movements of fin whales (Balaenoptera physalus) from Svalbard, Norway, revealed by satellite tracking

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Christian Lydersen ◽  
Jade Vacquié-Garcia ◽  
Mads Peter Heide-Jørgensen ◽  
Nils Øien ◽  
Christophe Guinet ◽  
...  
Keyword(s):  
Satellite Tracking ◽  
The Other ◽  
Life History Strategies ◽  
High Latitudes ◽  
Breeding Area ◽  
Balaenoptera Physalus ◽  
Westerly Direction ◽  
Satellite Transmitters ◽  
Fin Whales ◽  
Insight Into

Abstract Insight into animal movements is essential for understanding habitat use by individuals as well as population processes and species life-history strategies. In this study, we instrumented 25 fin whales with ARGOS satellite-transmitters in Svalbard, Norway, to study their movement patterns and behaviour (Area Restricted Search (ARS), transiting or unknown) during boreal autumn/early winter. Ten of the whales stayed in the tagging area (most northerly location: 81.68°N) for their entire tracking periods (max 45 days). The other 15 whales moved in a south-westerly direction; the longest track ended off the coast of northern Africa (> 5000 km from the tagging location) after 96 days. The whales engaged in ARS behaviour intermittently throughout their southward migrations. During transit phases the whales moved quickly; one individual maintained an average horizontal speed of 9.3 km/h (travelling 223 km per day) for a period of a week. This study documents that: (1) some fin whales might remain at high latitudes during winter; (2) the whales that do migrate probably feed along the way; (3) they can maintain high transiting speed for long periods and; (4) one breeding area for this species is likely located in deep, warm water some 100 km west of Morocco.

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