Ice ages depend, above all, on the inclination of the Earth

Ice ages depend, above all, on the inclination of the Earth

Both the changes in temperature and the impact of meteorites have caused five mass extinctions of terrestrial life, during which up to 90% of all species disappeared.

With regard to glaciations, these would take place, above all, due to the inclination of our planet , according to a new study by the University of Melbourne.

Interglacial period

Milankovitch cycles explain how orbital variations cause climate change on the planet. So we can summarize that:

  • Glaciations : high eccentricity, low inclination and a large distance between the Earth and the Sun. This causes seasons with little contrast.
  • Interglacial : low eccentricity, great inclination, and shorter distance between the Earth and the Sun. This causes contrasting seasons.

Earth is currently in an interglacial period, with the last glacial period ending about 10,000 years ago , so that what remains of the continental ice sheets that once spanned the world are now restricted to Greenland and Antarctica. .

According to the new study cited, the ice ages in the last million years ended when the tilt angle of the Earth’s axis approached higher values. While it is widely accepted that the 40,000-year cycles were driven by cyclical variation in Earth’s orbital tilt or obliquity, orbital forcing theories do not adequately explain post-Middle Pleistocene glacial-interglacial periods .

Beyond what was possible using less up-to-date environmental records, this new accurate dating chronology reveals the persistent influence of obliquity and insolation on the rhythm of Earth’s glacial-interglacial cycle.