Secular Tidal Torque from Ocean and Atmosphere: Revisited with New Approach
Abstract
The Earth's slow deceleration due to secular tidal torque was investigated by G. H. Darwin and later confirmed by diverse evidences, including solar eclipse record, paleontology fossil, satellite orbit analysis, lunar laser ranging. Most former investigators estimated the ocean tidal dissipation by evaluating work integral based on ocean tide model. We developed a new and direct formulation to assess tidal torque from ocean tide model. Using this formula and recent ocean tide model, we re-calculated ocean tidal torque and found -4.21E16 [Nm] for M2 tide and -0.67E16 [Nm] for S2 tide, etc. We also re-calculated atmospheric tidal torque similarly, and found it as +0.16E16 [Nm]. During our investigation we realized that a formerly unknown factor (slightly larger than 1.2) should be multiplied to the tidal torque integral.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFM.G11C0721N
- Keywords:
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- 1240 Satellite geodesy: results;
- GEODESY AND GRAVITY;
- 1241 Satellite geodesy: technical issues;
- GEODESY AND GRAVITY;
- 1243 Space geodetic surveys;
- GEODESY AND GRAVITY