Milankovitch Cycle
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The Milankovitch cycle is a term granted after Milutin Milanković, a serbian mathematician, geophysicist and climatologist. This term is used to describe periodic changes in Earth’s climate due to the movement of the Earth. The Milankovitch cycle shows that three factors- the precession of the earth axis, the Earth’s axial tilt (obliquity) and the Earth’s orbit eccentricity, could govern the climate pattern of the Earth. The exact timeline of the cycles of the three factors is shown below.
It is now known that the Earth’s orbit is not a perfect circle, but an eclipse with a small eccentricity that varies between 0.000055 to 0.0679. It takes about 413,000 years to complete a cycle. Axial tilt, similarly, has a periodicity of 41000 years and this tilt angle varies from 22.1° to 24.5°. Precession has a shorter periodicity than the axial tilt periodicity, being 26,000 years. These factors, including the interactions of Earth with other heavenly bodies, affect the length of the days on Earth and the solar insolation on Earth at each different latitudes. These will contribute to climate change significantly. It is partially the reason why there are periodic climate changes in the history of the Earth.
References
Fong Chao, B. (1996). “Concrete” Testimony to Milankovitch Cycle in Earth's changing obliquity. Eos, Transactions American Geophysical Union, 77(44), 433-433.