<p>An oscillation of about 6 years has been reported in Earth’s fluid core motions, magnetic field, rotation, and crustal deformations. Recently, a 6-year cycle has also been detected in several climatic parameters (e.g., sea level, surface temperature, precipitation, land ice, land hydrology, and atmospheric angular momentum). Here we suggest that the 6-year oscillations detected in the Earth’s deep interior, mantle rotation, and atmosphere are linked together, and that the core processes previously proposed as drivers of the 6-year cycle in the Earth’s rotation, cause in addition the atmosphere to oscillate together with the mantle, inducing fluctuations in the climate system with similar periodicities.</p>