Decadal fluctuations in Earth’s rotationas evidences of lithospheric drift over the asthenospere
The decadal instabilities in Earth’s rotation (DIER) are thought to be caused bythe interactions between the Earth’s core and its mantle. This hypothesissuccessfully explains whythere is a close correlation between DIER and the variations in the rate of the westward drift of thegeomagnetic eccentric dipole, since it is successfully reproduced by modeling of the redistribution ofthe angular momentum between the fluid core and the mantle of the Earth. However, the hypothesiscan not explain the close correlations of DIER: with the observable variations in the masses of theAntarctic and Greenland ice sheets; with the decade oscillations of thetypes of synoptic processes(i.e. the epochs of the atmospheric circulation); with the anomalies ofthe global temperature;and with regional anomalies of the cloudiness, precipitations, and otherclimatic characteristics. Analternative to the core-mantle interaction hypothesis is presentedhere. This alternative hypothesisclaims that the DIER are actually caused by fluctuations in the angular velocity of lithospheric driftover the asthenosphere. The sliding of the lithosphere over the asthenosphere is possible due to ofthe vibrational displacement mechanism produced by tidal forces. The lithospheric plates exhibitvibrational displacements over the asthenosphere in the horizontal direction by shear stresses causedby friction, wind, and ocean currents. There is abundant evidence supporting thislithospheric driftmodel.